2,064 results
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2. Systematic relations between the HIPPARCOS catalogue and major (fundamental) catalogues of the 20th century (Paper II)
- Author
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H. Schwan
- Subjects
Physics ,Software ,Space and Planetary Science ,business.industry ,Astronomy and Astrophysics ,Astrophysics ,business - Abstract
Presented are the systematic relations between the HIPPARCOS catalogue and major catalogues of the 20th century, not yet treated in Paper I. Colour-dependent errors in the catalogues are also determined and eliminated. The derived systematic relations allow one to reduce observations given in the system of one of the analyzed catalogues to the HIPPARCOS system. The necessary software and the required input data can be downloaded from http://www.ari.uni-heidelberg.de/fk6/sysdiff. Other catalogues may be added from time to time.
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- 2002
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3. The timing of relativistic proton acceleration in the 20 January 2005 flare, and other papers
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G. M. Simnett
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Proton (rocket family) ,Physics ,Timing error ,Solar flare ,Space and Planetary Science ,law ,Data needs ,Astronomy ,Astronomy and Astrophysics ,Acceleration (differential geometry) ,Astrophysics ,Flare ,law.invention - Abstract
In 2006 a timing error was discovered in the EPAM data from the ACE spacecraft, which has since been corrected. There are two publications where the interpretation of the data needs some revision on account of the error (Simnett 2006, AA Simnett et al. 2005, A&A, 440, 759). Here we publish the correct versions of the data and indicate where the discussion in the above papers needs modifying.
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- 2007
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4. The timing of relativistic proton acceleration in the 20 January 2005 flare, and other papers
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Simnett, G. M., primary
- Published
- 2007
- Full Text
- View/download PDF
5. New A&A editorial policy for papers about instrumentation
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Bertout, Claude, primary and Walmsley, Malcolm, additional
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- 2006
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6. RX J0042.3+4115: a stellar mass black hole binary identified in M 31, and other papers
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Barnard, R., primary, Kolb, U. C., additional, and Osborne, J. P., additional
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- 2006
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7. Systematic relations between the HIPPARCOS catalogue and major (fundamental) catalogues of the 20th century (Paper II)
- Author
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Schwan, H., primary
- Published
- 2002
- Full Text
- View/download PDF
8. Systematic relations between the HIPPARCOS catalogue and major (fundamental) catalogues of the 20th century (Paper I)
- Author
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Schwan, H., primary
- Published
- 2001
- Full Text
- View/download PDF
9. New A&A editorial policy for papers about instrumentation
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Claude Bertout and Malcolm Walmsley
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Physics ,Space and Planetary Science ,Section (archaeology) ,Astrophysics::Instrumentation and Methods for Astrophysics ,Systems engineering ,Astronomy and Astrophysics ,Instrumentation (computer programming) ,Astrophysics ,Computer Science::Digital Libraries ,Physics::History of Physics ,Astronomical instrumentation - Abstract
Astronomy & Astrophysics introduces a new editorial policy for papers submitted to Section 13 (Astronomical Instrumentation).
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- 2006
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10. RX J0042.3+4115: a stellar mass black hole binary identified in M 31, and other papers
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J. P. Osborne, Robin Barnard, and Ulrich Kolb
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Physics ,Black hole ,Spectral index ,Accretion (meteorology) ,Stellar mass ,Space and Planetary Science ,X-ray binary ,Astronomy ,Astronomy and Astrophysics ,Stellar black hole ,Astrophysics ,Low Mass ,Power law - Abstract
In this work we have previously identified low mass X-ray binaries (LMXBs) in XMM-Newton observations of M 31 from their characteristic power density spectra (PDS). These PDS were characterised by a broken power law, with the spectral index changing from ∼0 to ∼1 at a break frequency in the range 0.01−1 Hz, and signify LMXBs in their low accretion-rate state (van der Klis 1994, ApJ, 92, 511). However, the observed PDS were false positives resulting from the improper treatment of non-simultaneous lightcurves; the corrected PDS are featureless (see Barnard et al. 2007, A&A, 469, 875, for details). As a result, there is no evidence for black hole primaries in the subjects of these papers.
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- 2006
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11. First Observations from the SPICE EUV Spectrometer on Solar Orbiter
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Andrzej Fludra, M. Caldwell, A. Giunta, T. Grundy, S. Guest, S. Leeks, S. Sidher, F. Auchère, M. Carlsson, D. Hassler, H. Peter, R. Aznar Cuadrado, É. Buchlin, S. Caminade, C. DeForest, T. Fredvik, M. Haberreiter, L. Harra, M. Janvier, T. Kucera, D. Müller, S. Parenti, W. Schmutz, U. Schühle, S.K. Solanki, L. Teriaca, W.T. Thompson, S. Tustain, D. Williams, P.R. Young, and L.P. Chitta
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Solar Physics - Abstract
Aims. We present first science observations taken during the commissioning activities of the Spectral Imaging of the Coronal Environment (SPICE) instrument on the ESA/NASA Solar Orbiter mission. SPICE is a high-resolution imaging spectrometer operating at extreme ultraviolet (EUV) wavelengths. In this paper we illustrate the possible types of observations to give prospective users a better understanding of the science capabilities of SPICE. Methods. We have reviewed the data obtained by SPICE between April and June 2020 and selected representative results obtained with different slits and a range of exposure times between 5 s and 180 s. Standard instrumental corrections have been applied to the raw data. Results. The paper discusses the first observations of the Sun on different targets and presents an example of the full spectra from the quiet Sun, identifying over 40 spectral lines from neutral hydrogen and ions of carbon, oxygen, nitrogen, neon, sulphur, magnesium, and iron. These lines cover the temperature range between 20,000 K and 1 million K (10MK in flares), providing slices of the Sun’s atmosphere in narrow temperature intervals. We provide a list of count rates for the 23 brightest spectral lines. We show examples of raster images of the quiet Sun in several strong transition region lines, where we have found unusually bright, compact structures in the quiet Sun network, with extreme intensities up to 25 times greater than the average intensity across the image. The lifetimes of these structures can exceed 2.5 hours. We identify them as a transition region signature of coronal bright points and compare their areas and intensity enhancements. We also show the first above-limb measurements with SPICE above the polar limb in C III,O VI, and Ne VIII lines, and far off limb measurements in the equatorial plane in Mg IX, Ne VIII, and O VI lines. We discuss the potential to use abundance diagnostics methods to study the variability of the elemental composition that can be compared with in situ measurements to help confirm the magnetic connection between the spacecraft location and the Sun’s surface, and locate the sources of the solar wind. Conclusions. The SPICE instrument successfully performs measurements of EUV spectra and raster images that will make vital contributions to the scientific success of the Solar Orbiter mission
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- 2021
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12. Modeling the propagation of very-high-energy gamma-rays with the CRbeam code: Comparison with CRPropa and ELMAG codes
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Kalashev, O., Korochkin, A., Neronov, A., Semikoz, D., HEP, INSPIRE, AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)
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gamma ray: propagation ,Cherenkov Telescope Array ,Astrophysics::High Energy Astrophysical Phenomena ,FOS: Physical sciences ,magnetic field ,Astrophysics::Cosmology and Extragalactic Astrophysics ,gamma ray: detector ,structure ,Monte Carlo ,High Energy Astrophysical Phenomena (astro-ph.HE) ,electron positron ,cosmic radiation: propagation ,background ,photon ,imaging ,Astronomy and Astrophysics ,redshift ,sensitivity ,observatory ,gamma ray: emission ,gamma ray: VHE ,Space and Planetary Science ,spectral ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,[PHYS.ASTR] Physics [physics]/Astrophysics [astro-ph] ,Astrophysics - High Energy Astrophysical Phenomena - Abstract
Very-high-energy gamma rays produce electron positron pairs in interactions with low-energy photons of extragalactic background light during propagation through the intergalactic medium. The electron-positron pairs generate secondary gamma rays detectable by gamma-ray telescopes. This secondary emission can be used to detect intergalactic magnetic fields (IGMF) in the voids of large-scale structure. A new gamma-ray observatory, namely, Cherenkov Telescope Array (CTA), will provide an increase in sensitivity for detections of these secondary gamma-ray emission and enable the measurement of its properties for sources at cosmological distances. The interpretation of the CTA data, including detection of IGMF and study of its properties and origins, will require precision modeling of the primary and secondary gamma-ray fluxes. We asses the precision of the modeling of the secondary gamma-ray emission using model calculations with publicly available Monte-Carlo codes CRPropa and ELMAG and compare their predictions with theoretical expectations and with model calculations of a newly developed CRbeam code. We find that model predictions of different codes differ by up to 50% for low-redshift sources, with discrepancies increasing up to order-of-magnitude level with the increasing source redshifts. We identify the origin of these discrepancies and demonstrate that after eliminating the inaccuracies found, the discrepancies between the three codes are reduced to 10% when modeling nearby sources with z~0.1. We argue that the new CRbeam code provides reliable predictions for spectral, timing and imaging properties of the secondary gamma-ray signal for both nearby and distant sources with z~1. Thus, it can be used to study gamma-ray sources and IGMF with a level of precision that is appropriate for the prospective CTA study of the effects of gamma-ray propagation through the intergalactic medium., V2: 15 pages, 12 figures, version accepted by A&A. While the paper was under review, new versions of the codes CRPropa3-3.2 and ELMAG 3.03 were released in which many of the comments presented in this paper were taken into account (see text for the details)
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- 2023
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13. The computation of interstellar extinction in photoionized nebulae
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Morisset, Christophe, Corradi, Romano L. M., García-Rojas, Jorge, Mampaso, Antonio, Jones, David, Kwitter, Karen B., Magrini, Laura, and Villaver, Eva
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Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics - Instrumentation and Methods for Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Instrumentation and Methods for Astrophysics (astro-ph.IM) - Abstract
Ueta & Otsuka (2021) proposed a method, named as the "Proper Plasma Analysis Practice", to analyze spectroscopic data of ionized nebulae. The method is based on a coherent and simultaneous determination of the reddening correction and physical conditions in the nebulae. The same authors (Ueta & Otsuka 2022, UO22) reanalyzed the results of Galera-Rosillo et al. (2022, GR22) on nine of the brightest planetary nebulae in M31. They claim that, if standard values of the physical conditions are used to compute the extinction instead of their proposed method, extinction correction is underestimated by more than 50% and hence, ionic and elemental abundance determinations, especially the N/O ratio, are incorrect. Several tests were performed to assess the accuracy of the results of GR22, when determining: i) the extinction coefficient, ii) the electron temperature and density, and iii) the ionic abundances. In the latter case, N+ /H+ ionic abundance was recalculated using both H_alpha and H_beta as the reference H I emissivity. The analysis shows that the errors introduced by adopting standard values of the plasma conditions by GR22 are small, within their quoted uncertainties. On the other hand, the interstellar extinction in UO22 is found to be overestimated for five of the nine nebulae considered. This propagates into their analysis of the properties of the nebulae and their progenitors. The python notebook used to generate all the results presented in this paper are of public access on a Github repository. The results from GR22 are proven valid and the conclusions of the paper hold firmly. Although the PPAP is, in principle, a recommended practice, we insist that it is equally important to critically assess which H I lines are to be included in the determination of the interstellar extinction coefficient, and to assert that physical results are obtained for the undereddened line ratios., Accepted for publication in A&A Letter
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- 2023
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14. Gaia Data Release 3. The second Gaia catalogue of long-period variable candidates
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Lebzelter, T., Mowlavi, N., Lecoeur-Taibi, I., Trabucchi, M., Audard, M., García-Lario, P., Gavras, P., Holl, B., Jevardat de Fombelle, G., Nienartowicz, K., Rimoldini, L., and Eyer, L.
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Astrophysics - Solar and Stellar Astrophysics ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Solar and Stellar Astrophysics (astro-ph.SR) - Abstract
The third Gaia Data Release, covering 34 months of data, includes the second Gaia catalogue of long-period variables (LPVs), with G variability amplitudes larger than 0.1 mag (5-95% quantile range). The paper describes the production and content of this catalogue, and the methods used to compute the published variability parameters and identify C-star candidates. We applied various filtering criteria to minimise contamination by other kinds of variables. The variability parameters, period and amplitude, were derived from model fits to the G-band light curves, wherever possible. C stars were identified using their molecular signature in the low-resolution RP spectra. The catalogue contains 1 720 558 LPV candidates, including 392 240 stars with published periods (ranging from 35 to1000 days) and 546 468 stars classified as C-stars candidates. Comparison with literature data (OGLE and ASAS-SN) leads to an estimated 80% of completeness. The recovery rate is about 90% for the most regular stars (typically Miras) and 60% for semi-regular and irregular ones. At the same time, the number of known LPVs is increased by a large factor with respect to the literature data, especially in crowded regions, and the contamination is estimated to be below two percents. Our C-star classification, based on solid theoretical arguments, is consistent with spectroscopically identified C stars in the literature. Caution must however be taken if the S/N ratio is small, in crowded regions or if the source is reddened by some kind of extinction. The quality and potential of the catalogue are illustrated by presenting and discussing LPVs in the solar neighbourhood, in globular clusters and in galaxies of the Local Group. This is the largest all-sky catalogue of LPVs to date with a photometric depth down to G=20 mag, providing a unique data set for research on late stages of stellar evolution., This paper is part of Gaia Data Release 3 (DR3). Accepted for publication in A&A. 32 pages, 51 figures
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- 2022
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15. A new dynamical modeling of the WASP-47 system with CHEOPS observations
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Nascimbeni, V., Borsato, L., Zingales, T., Piotto, G., Pagano, I., Beck, M., Broeg, C., Ehrenreich, D., Hoyer, S., Majidi, F. Z., Granata, V., Sousa, S. G., Wilson, T. G., Van Grootel, V., Bonfanti, A., Salmon, S., Mustill, A. J., Delrez, L., Alibert, Y., Alonso, R., Anglada, G., Bàrczy, T., Barrado, D., Barros, S. C. C., Baumjohann, W., Beck, T., Benz, W., Bergomi, M., Billot, N., Bonfils, X., Brandeker, A., Cabrera, J., Charnoz, S., Collier Cameron, A., Csizmadia, Sz., Cubillos, P. E., Davies, M. B., Deleuil, M., Deline, A., Demangeon, O. D. S., Demory, B. -O., Erikson, A., Fortier, A., Fossati, L., Fridlund, M., Gandolfi, D., Gillon, M., Güdel, M., Isaak, K. G., Kiss, L. L., Laskar, J., Lecavelier des Etangs, A., Lendl, M., Lovis, C., Luque, R., Magrin, D., Maxted, P. F. L., Mordasini, C., Olofsson, G., Ottensamer, R., Palle, E., Peter, G., Piazza, D., Pollacco, D., Queloz, D., Ragazzoni, R., Rando, N., Ratti, F., Rauer, H., Ribas, I., Santos, N. C., Scandariato, G., Segransan, D., Simon, A. E., Smith, A. M. S., Steinberger, M., Steller, M., Szabó, Gy. M., Thomas, N., Udry, S., Venturini, J., Walton, N. A., Wolter, D., Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, Institut de Physique du Globe de Paris (IPGP (UMR_7154)), Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Institut de Mécanique Céleste et de Calcul des Ephémérides (IMCCE), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Lille-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Ministerio de Ciencia e Innovación (España), European Research Council, European Commission, Science & Technology Facilities Council, University of St Andrews. School of Physics and Astronomy, and University of St Andrews. St Andrews Centre for Exoplanet Science
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Earth and Planetary Astrophysics (astro-ph.EP) ,planets and satellites: detection ,photometric [Techniques] ,500 Naturwissenschaften und Mathematik::520 Astronomie::520 Astronomie und zugeordnete Wissenschaften ,Planets ,FOS: Physical sciences ,planets and satellites: general ,Astronomy and Astrophysics ,3rd-DAS ,detection [Planets and satellites] ,techniques: photometric ,Astrophysics - Solar and Stellar Astrophysics ,[SDU]Sciences of the Universe [physics] ,Space and Planetary Science ,MCP ,photometric ,planets and satellites: general [techniques] ,general [Satellites] ,Solar and Stellar Astrophysics (astro-ph.SR) ,Astrophysics - Earth and Planetary Astrophysics - Abstract
Full list of authors: Nascimbeni, V.; Borsato, L.; Zingales, T.; Piotto, G.; Pagano, I.; Beck, M.; Broeg, C.; Ehrenreich, D.; Hoyer, S.; Majidi, F. Z.; Granata, V.; Sousa, S. G.; Wilson, T. G.; Van Grootel, V.; Bonfanti, A.; Salmon, S.; Mustill, A. J.; Delrez, L.; Alibert, Y.; Alonso, R.; Anglada, G.; Barczy, T.; Barrado, D.; Barros, S. C. C.; Baumjohann, W.; Beck, T.; Benz, W.; Bergomi, M.; Billot, N.; Bonfils, X.; Brandeker, A.; Cabrera, J.; Charnoz, S.; Cameron, A. Collier; Csizmadia, Sz.; Cubillos, P. E.; Davies, M. B.; Deleuil, M.; Deline, A.; Demangeon, O. D. S.; Demory, B. -o.; Erikson, A.; Fortier, A.; Fossati, L.; Fridlund, M.; Gandolfi, D.; Gillon, M.; Guedel, M.; Isaak, K. G.; Kiss, L. L.; Laskar, J.; des Etangs, A. Lecavelier; Lendl, M.; Lovis, C.; Luque, R.; Magrin, D.; Maxted, P. F. L.; Mordasini, C.; Olofsson, G.; Ottensamer, R.; Palle, E.; Peter, G.; Piazza, D.; Pollacco, D.; Queloz, D.; Ragazzoni, R.; Rando, N.; Ratti, F.; Rauer, H.; Ribas, I.; Santos, N. C.; Scandariato, G.; Segransan, D.; Simon, A. E.; Smith, A. M. S.; Steinberger, M.; Steller, M.; Szabo, Gy. M.; Thomas, N.; Udry, S.; Venturini, J.; Walton, N. A.; Wolter, D.--This is an Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited., Among the hundreds of known hot Jupiters (HJs), only five have been found to have companions on short-period orbits. Within this rare class of multiple planetary systems, the architecture of WASP-47 is unique, hosting an HJ (planet-b) with both an inner and an outer sub-Neptunian mass companion (-e and -d, respectively) as well as an additional non-transiting, long-period giant (-c). The small period ratio between planets -b and -d boosts the transit time variation (TTV) signal, making it possible to reliably measure the masses of these planets in synergy with the radial velocity (RV) technique. In this paper, we present new space- and ground-based photometric data of WASP-47b and WASP-47-d, including 11 unpublished light curves from the ESA mission CHaracterising ExOPlanet Satellite (CHEOPS). We analyzed the light curves in a homogeneous way together with all the publicly available data to carry out a global N-body dynamical modeling of the TTV and RV signals. We retrieved, among other parameters, a mass and density for planet -d of Md = 15.5 ± 0.8 M⊕ and ρd = 1.69 ± 0.22 g cm−3, which is in good agreement with the literature and consistent with a Neptune-like composition. For the inner planet (-e), we found a mass and density of Me = 9.0 ± 0.5 M⊕ and ρe = 8.1 ± 0.5 g cm−3, suggesting an Earth-like composition close to other ultra-hot planets at similar irradiation levels. Though this result is in agreement with previous RV plus TTV studies, it is not in agreement with the most recent RV analysis (at 2.8σ), which yielded a lower density compatible with a pure silicate composition. This discrepancy highlights the still unresolved issue of suspected systematic offsets between RV and TTV measurements. In this paper, we also significantly improve the orbital ephemerides of all transiting planets, which will be crucial for any future follow-up. © The Authors 2023., CHEOPS is an ESA mission in partnership with Switzerland with important contributions to the payload and the ground segment from Austria, Belgium, France, Germany, Hungary, Italy, Portugal, Spain, Sweden, and the United Kingdom. The CHEOPS Consortium would like to gratefully acknowledge the support received by all the agencies, offices, universities, and industries involved. Their flexibility and willingness to explore new approaches were essential to the success of this mission. L.Bo., G.Br., V.Na., I.Pa., G.Pi., R.Ra., G.Sc., V.Si., and T.Zi. acknowledge support from CHEOPS ASI-INAF agreement no. 2019-29-HH.0. F.Z.M. is funded by “Bando per il Finanziamento di Assegni di Ricerca Progetto Dipartimenti di Eccellenza Anno 2020” and is co-funded in agreement with ASI-INAF no. 2019-29-HH.0 from 26 Nov/2019 for “Italian participation in the operative phase of CHEOPS mission” (DOR – Prof. Piotto). This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (project FOUR ACES. S.H. gratefully acknowledges CNES funding through the grant 837319. S.G.S. acknowledges support from FCT through FCT contract nr. CEECIND/00826/2018 and POPH/FSE (EC). A.C.C. and T.W. acknowledge support from STFC consolidated grant numbers ST/R000824/1 and ST/V000861/1, and UKSA grant number ST/R003203/1. V.V.G. is an F.R.S-FNRS Research Associate. The Belgian participation to CHEOPS has been supported by the Belgian Federal Science Policy Office (BELSPO) in the framework of the PRODEX Program, and by the University of Liège through an ARC grant for Concerted Research Actions financed by the Wallonia-Brussels Federation. L.D. is an F.R.S.-FNRS Postdoctoral Researcher. Y.A. and M.J.H. acknowledge the support of the Swiss National Fund under grant 200020_172746. We acknowledge support from the Spanish Ministry of Science and Innovation and the European Regional Development Fund through grants ESP2016-80435-C2-1-R, ESP2016-80435-C2-2-R, PGC2018-098153-B-C33, PGC2018-098153-B-C31, ESP2017-87676-C5-1-R, MDM-2017-0737 Unidad de Excelencia Maria de Maeztu-Centro de Astrobiologia (INTA-CSIC), as well as the support of the Generalitat de Catalunya/CERCA programme. The MOC activities have been supported by the ESA contract no. 4000124370. S.C.C.B. acknowledges support from FCT through FCT contracts nr. IF/01312/2014/CP1215/CT0004. X.B., S.C., D.G., M.F. and J.L. acknowledge their role as ESA-appointed CHEOPS science team members. A.Br. was supported by the SNSA. A.C.C. acknowledges support from STFC consolidated grant numbers ST/R000824/1 and ST/V000861/1, and UKSA grant number ST/R003203/1. This project was supported by the CNES. This work was supported by FCT – Fundação para a Ciência e a Tecnologia through national funds and by FEDER through COMPETE2020 -Programa Operacional Competitividade e Internacionalizacão by these grants: UID/FIS/04434/2019, UIDB/04434/2020, UIDP/04434/2020, PTDC/FIS-AST/32113/2017 & POCI-01-0145-FEDER- 032113, PTDC/FIS-AST/28953/2017 & POCI-01-0145-FEDER-028953, PTDC/FIS-AST/28987/ 2017 & POCI-01-0145-FEDER-028987, O.D.S.D. is supported in the form of work contract (DL 57/2016/CP1364/CT0004) funded by national funds through FCT. B.-O.D. acknowledges support from the Swiss State Secretariat for Education, Research and Innovation (SERI) under contract number MB22.00046. M.F. and C.M.P. gratefully acknowledge the support of the Swedish National Space Agency (DNR 65/19, 174/18). A.J.M. acknowledges support from the Swedish National Space Agency (career grant 120/19C). D.G. gratefully acknowledges financial support from the CRT foundation under Grant No. 2018.2323 “Gaseousor rocky? Unveiling the nature of small worlds”. M.G. is an F.R.S.-FNRS Senior Research Associate. K.G.I. is the ESA CHEOPS Project Scientist and is responsible for the ESA CHEOPS Guest Observers Programme. She does not participate in, or contribute to, the definition of the Guaranteed Time Programme of the CHEOPS mission through which observations described in this paper have been taken, nor to any aspect of target selection for the programme. This work was granted access to the HPC resources of MesoPSL financed by the Region Île-de-France and the project Equip@Meso (reference ANR-10-EQPX-29-01) of the programme Investissements d’Avenir supervised by the Agence Nationale pour la Recherche. M.L. acknowledges support of the Swiss National Science Foundation under grant number PCEFP2_194576. P.M. acknowledges support from STFC research grant number ST/M001040/1. This work was also partially supported by a grant from the Simons Foundation (PI Queloz, grant number 327127). I.R.I. acknowledges support from the Spanish Ministry of Science and Innovation and the European Regional Development Fund through grant PGC2018-098153-B-C33, as well as the support of the Generalitat de Catalunya/CERCA programme. Gy.M.Sz. acknowledges the support of the Hungarian National Research, Development and Innovation Office (NKFIH) grant K-125015, a PRODEX Experiment Agreement No. 4000137122, the Lendület LP2018-7/2021 grant of the Hungarian Academy of Science and the support of the city of Szombathely. N.A.W. acknowledges UKSA grant ST/R004838/1. This work was supported by FCT – Fundação para a Ciência e a Tecnologia through national funds and by FEDER through COMPETE2020 – Programa Operacional Competitividade e Internacionalização by these grants: UID/FIS/04434/2019; UIDB/04434/2020; UIDP/04434/2020. D.B. has been partially funded by MCIN/AEI/10.13039/501100011033 grants PID2019-107061GB-C61 and MDM-2017-0737. This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (project FOUR ACES; grant agreement no. 724427). It has also been carried out in the frame of the National Centre for Competence in Research PlanetS supported by the Swiss National Science Foundation (SNSF). D.E. acknowledges financial support from the Swiss National Science Foundation for project 200021_200726. P.E.C. is funded by the Austrian Science Fund (FWF) Erwin Schroedinger Fellowship, program J4595-N. S.S. has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant agreement no. 833925, project STAREX). This research has made use of the SIMBAD database (operated at CDS, Strasbourg, France; Wenger et al. 2000), the VAR-TOOLS Light Curve Analysis Program (version 1.39 released October 30, 2020, Hartman & Bakos 2016), TOPCAT and STILTS (Taylor 2005, 2006), the NASA Exoplanet archive (Akeson et al. 2013). Based on observations made with the REM Telescope, INAF Chile., With funding from the Spanish government through the "Severo Ochoa Centre of Excellence" accreditation (CEX2021-001131-S).
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- 2023
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16. Spectroscopic and evolutionary analyses of the binary system AzV 14 outline paths toward the WR stage at low metallicity
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Pauli, D., Oskinova, L.M., Hamann, W.-R., Bowman, D.M., Todt, H., Shenar, T., Sander, A.A.C., Erba, C., Gómez-González, V.M.A., Kehrig, C., Klencki, J., Kuiper, Rolf, Mehner, A., de Mink, S.E., Oey, M.S., Ramachandran, V., Schootemeijer, A., Serantes, S. Reyero, Wofford, A., Reyero Serantes, S., Ministerio de Ciencia e Innovación (España), Junta de Andalucía, European Commission, and German Research Foundation
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Binaries: eclipsing ,FOS: Physical sciences ,Astronomy and Astrophysics ,Binaries: spectroscopic ,Physik (inkl. Astronomie) ,End hunger, achieve food security and improved nutrition and promote sustainable agriculture ,Astrophysics - Astrophysics of Galaxies ,Stars: early-type ,Astrophysics - Solar and Stellar Astrophysics ,Binaries: close ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,Solar and Stellar Astrophysics (astro-ph.SR) ,Stars: fundamental parameters ,Stars: individual: AzV 14 - Abstract
This is an Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited., Context. The origin of the observed population of Wolf-Rayet (WR) stars in low-metallicity galaxies, such as the Small Magellanic Cloud (SMC), is not yet understood. Standard, single-star evolutionary models predict that WR stars should stem from very massive O-type star progenitors, but these are very rare. On the other hand, binary evolutionary models predict that WR stars could originate from primary stars in close binaries. Aims. We conduct an analysis of the massive O star, AzV 14, to spectroscopically determine its fundamental and stellar wind parameters, which are then used to investigate evolutionary paths from the O-type to the WR stage with stellar evolutionary models. Methods. Multi-epoch UV and optical spectra of AzV 14 are analyzed using the non-local thermodynamic equilibrium (LTE) stellar atmosphere code PoWR. An optical TESS light curve was extracted and analyzed using the PHOEBE code. The obtained parameters are put into an evolutionary context, using the MESA code. Results. AzV 14 is a close binary system with a period of P = 3.7058 ± 0.0013 d. The binary consists of two similar main sequence stars with masses of M1, 2 ≈ 32 M⊙. Both stars have weak stellar winds with mass-loss rates of log Ṁ/(M⊙ yr−1) = −7.7 ± 0.2. Binary evolutionary models can explain the empirically derived stellar and orbital parameters, including the position of the AzV 14 components on the Hertzsprung-Russell diagram, revealing its current age of 3.3 Myr. The model predicts that the primary will evolve into a WR star with Teff ≈ 100 kK, while the secondary, which will accrete significant amounts of mass during the first mass transfer phase, will become a cooler WR star with Teff ≈ 50 kK. Furthermore, WR stars that descend from binary components that have accreted significant amount of mass are predicted to have increased oxygen abundances compared to other WR stars. This model prediction is supported by a spectroscopic analysis of a WR star in the SMC. Conclusions. Inspired by the binary evolutionary models, we hypothesize that the populations of WR stars in low-metallicity galaxies may have bimodal temperature distributions. Hotter WR stars might originate from primary stars, while cooler WR stars are the evolutionary descendants of the secondary stars if they accreted a significant amount of mass. These results may have wide-ranging implications for our understanding of massive star feedback and binary evolution channels at low metallicity. © The Authors 2023., The results presented in this paper are based on observations obtained with the NASA/ESA Hubble Space Telescope, retrieved from MAST at the Space Telescope Science Institute (STScI). STScI is operated by the Association of Universities for Research in Astronomy, Inc. under NASA contract NAS 5-26555. Support to MAST for these data are provided by the NASA Office of Space Science via grant NAG5-7584 and by other grants and contracts. The TESS data presented in this paper were obtained from MAST at the STScI. Funding for the TESS mission was provided by the NASA Explorer Program. Furthermore, its conclusions are based on observations collected at the European Southern Observatory (ESO) under the program 098.A-0049. The authors thank the managing committee of XShootU and Andrea Mehner for preparing the OBs of the XShootU project. This work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. D.P. and S.R.S. acknowledge financial support by the Deutsches Zentrum für Luft und Raumfahrt (DLR) grants FKZ 50OR2005 and 50OR2108. A.A.C.S. and V.R. acknowledge support by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) in the form of an Emmy Noether Research Group – Project-ID 445674056 (SA4064/1-1, PI: Sander). D.M.B. gratefully acknowledges a senior postdoctoral fellowship from the Research Foundation Flanders (FWO) with grant agreement number 1286521N. R.K. acknowledges financial support via the Heisenberg Research Grant funded by the German Research Foundation (DFG) under grant no. KU 2849/9. C.K. acknowledges financial support from the Spanish Ministerio de Economía y Competitividad under grants AYA2016-79724-C4-4-P and PID2019-107408GB-C44, from Junta de Andalucía Excellence Project P18-FR-2664, and from the State Agency for Research of the Spanish MCIU through the ‘Center of Excellence Severo Ochoa’ award for the Instituto de Astrofísica de Andalucía (SEV-2017-0709). T.S. acknowledges support from the European Union’s Horizon 2020 under the Marie Skłodowska-Curie grant agreement No. 101024605. The collaboration of coauthors was facilitated by support from the International Space Science Institute (ISSI, Bern)., With funding from the Spanish government through the "Severo Ochoa Centre of Excellence" accreditation (CEX2021-001131-S).
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- 2023
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17. Gaia Data Release 3. Catalogue validation
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Babusiaux, C., Fabricius, C., Khanna, S., Muraveva, T., Reylé, C., Spoto, F., Vallenari, A., Luri, X., Arenou, F., Alvarez, M. A., Anders, F., Antoja, T., Balbinot, E., Barache, C., Bauchet, N., Bossini, D., Busonero, D., Cantat-Gaudin, T., Carrasco, J. M., Dafonte, C., Diakite, S., Figueras, F., Garcia-Gutierrez, A., Garofalo, A., Helmi, A., Jimenez-Arranz, O., Jordi, C., Kervella, P., Kostrzewa-Rutkowska, Z., Leclerc, N., Licata, E., Manteiga, M., Masip, A., Monguio, M., Ramos, P., Robichon, N., Robin, A. C., Romero-Gomez, M., Saez, A., Santovena, R., Spina, L., Elipe, G. Torralba, and Weiler, M.
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Earth and Planetary Astrophysics (astro-ph.EP) ,Astrophysics - Solar and Stellar Astrophysics ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics - Instrumentation and Methods for Astrophysics ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,Astrophysics - Astrophysics of Galaxies ,Solar and Stellar Astrophysics (astro-ph.SR) ,Astrophysics - Earth and Planetary Astrophysics - Abstract
The third gaia data release (DR3) provides a wealth of new data products. The early part of the release, Gaia EDR3, already provided the astrometric and photometric data for nearly two billion sources. The full release now adds improved parameters compared to Gaia DR2 for radial velocities, astrophysical parameters, variability information, light curves, and orbits for Solar System objects. The improvements are in terms of the number of sources, the variety of parameter information, precision, and accuracy. For the first time, Gaia DR3 also provides a sample of spectrophotometry and spectra obtained with the Radial Velocity Spectrometer, binary star solutions, and a characterisation of extragalactic object candidates. Before the publication of the catalogue, these data have undergone a dedicated transversal validation process. The aim of this paper is to highlight limitations of the data that were found during this process and to provide recommendations for the usage of the catalogue. The validation was obtained through a statistical analysis of the data, a confirmation of the internal consistency of different products, and a comparison of the values to external data or models. Gaia DR3 is a new major step forward in terms of the number, diversity, precision, and accuracy of the Gaia products. As always in such a large and complex catalogue, however, issues and limitations have also been found. Detailed examples of the scientific quality of the Gaia DR3 release can be found in the accompanying data-processing papers as well as in the performance verification papers. Here we focus only on the caveats that the user should be aware of to scientifically exploit the data., Published in the A&A Gaia Data Release 3 special issue
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18. Gaia Data Release 3: Exploring and mapping the diffuse interstellar band at 862 nm
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Gaia collaboration, Schultheis, M., Zhao, H., Zwitter, T., Marshall, D. J., Drimmel, R., Frémat, Y., Bailer-Jones, C. A. L., Recio-Blanco, A., Kordopatis, G., de Laverny, P., Andrae, R., Dharmawardena, T. E., Fouesneau, M., and Sordo, R.
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kinematics and dynamics [ISM] ,Space and Planetary Science ,Astronomy ,Astronomy and Astrophysics ,lines and bands [ISM] ,dust, extinction ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Physical Organic Chemistry ,Astrophysics::Galaxy Astrophysics - Abstract
Diffuse interstellar bands (DIBs) are common interstellar absorption features in spectroscopic observations but their origins remain unclear. DIBs play an important role in the life cycle of the interstellar medium (ISM) and can also be used to trace Galactic structure. Here, we demonstrate the capacity of the Gaia-Radial Velocity Spectrometer (RVS) in Gaia DR3 to reveal the spatial distribution of the unknown molecular species responsible for the most prominent DIB at 862 nm in the RVS passband, exploring the Galactic ISM within a few kiloparsecs from the Sun. The DIBs are measured within the GSP-Spec module using a Gaussian profile fit for cool stars and a Gaussian process for hot stars. In addition to the equivalent widths and their uncertainties, Gaia DR3 provides their characteristic central wavelength, width, and quality flags. We present an extensive sample of 476.117 individual DIB measurements obtained in a homogeneous way covering the entire sky. We compare spatial distributions of the DIB carrier with interstellar reddening and find evidence that DIB carriers are present in a local bubble around the Sun which contains nearly no dust. We characterised the DIB equivalent width with a local density of $0.19 \pm 0.04$ Angstr\"om/kpc and a scale height of $\rm 98.60_{-8.46}^{+11.10}$ pc. The latter is smaller than the dust scale height, indicating that DIBs are more concentrated towards the Galactic plane. We determine the rest-frame wavelength with unprecedented precision ($\rm \lambda_{0} = 8620.86\, \pm 0.019$ Angstr\"om in air) and reveal a remarkable correspondence between the DIB velocities and the CO gas velocities, suggesting that the 862 nm DIB carrier is related to macro-molecules., Comment: This is a Gaia Performance Verification Paper accepted for publication in A&A. The full author list is in the paper
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19. The miniJPAS Survey: Detection of the double-core Lyα morphology for two high-redshift QSOs
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Rahna, P. T., Zheng, Zhen-Ya, Chies-Santos, A. L., Cai, Z. Y., Spinoso, Daniele, Márquez, Isabel, Overzier, Roderik, Abramo, L. R., Bonoli, S., Kehrig, C., Díaz-García, L. A., Pović, Mirjana, Soria, R., Diego, José María, Broadhurst, Tom, González Delgado, Rosa M., Alcaniz, J., Benítez, Narciso, Carneiro, Saulo, Cenarro, A. J., Cristóbal-Hornillos, David, Dupke, R. A., Ederoclite, Alessandro, Hernán-Caballero, Antonio, López-Sanjuan, C., Marín-Franch, Antonio, Mendes de Oliveira, C., Moles, Mariano, Sodré Jr., L., Taylor, K., Varela, Jesús, Vázquez Ramió, H., JPAS team, National Science Foundation (US), Pioneer Fund, Conselho Nacional de Desenvolvimento Científico e Tecnológico (Brasil), Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul, Chinese Academy of Sciences, Japan Society for the Promotion of Science, Japan Science and Technology Agency, Gobierno de Aragón, European Commission, Fondo de Inversiones de Teruel, Ministerio de Ciencia, Innovación y Universidades (España), National Natural Science Foundation of China, Fundações de Amparo à Pesquisa (Brasil), University of Tartu, Agencia Estatal de Investigación (España), and National Astronomical Observatory of China
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Quasars: general ,Quasars: emission lines ,Space and Planetary Science ,Galaxies: high-redshift ,Galaxies: evolution ,Astronomy and Astrophysics ,Galaxies: formation ,Intergalactic medium - Abstract
Extragalactic astronomy., [Context] The Lyα emission is an important tracer of neutral gas in a circum-galactic medium (CGM) around high-z quasi-stellar objects (QSOs). The origin of Lyα emission around QSOs is still under debate, bringing on significant implications for galaxy formation and evolution., [Aims] In this paper, we study Lyα nebulae around two high redshift QSOs, SDSS J141935.58+525710.7 at z = 3.218 (hereafter QSO1) and SDSS J141813.40+525240.4 at z = 3.287 (hereafter QSO2), from the miniJPAS survey within the All-wavelength Extended Groth Strip International Survey (AEGIS) field., [Methods] Using the contiguous narrow-band (NB) images from the miniJPAS survey and Sloan Digital Sky Survey (SDSS) spectra, we analyzed their morphology, nature, and origin., [Results] We report the serendipitous detection of double-core Lyα morphology around two QSOs, which is rarely seen among other QSOs. The separations of the two Lyα cores are 11.07 ± 2.26 kpcs (1.47 ± 0.3″) and 9.73 ± 1.55 kpcs (1.31 ± 0.21″), with Lyα line luminosities of ∼3.35 × 1044 erg s−1 and ∼6.99 × 1044 erg s −1 for QSO1 and QSO2, respectively. The miniJPAS NB images show evidence of extended Lyα and CIV morphology for both QSOs and extended HeII morphology for QSO1., [Conclusions] These two QSOs may be potential candidates for the new enormous Lyman alpha nebula (ELAN) found from the miniJPAS survey due to their extended morphology in the shallow depth and relatively high Lyα luminosities. We suggest that galactic outflows are the major powering mechanism for the double-core Lyα morphology. Considering the relatively shallow exposures of miniJPAS, the objects found here could merely form the cusp of a promising number of such objects that will be uncovered in the upcoming full Javalambre-Physics of the Accelerated Universe Astrophysical Survey (J-PAS) survey and deep integral field units (IFU) observations with 8–10 m telescopes will be essential for constraining the underlying physical mechanism that is responsible for the double-cored morphology., Z.Y.Z. acknowledges support by the National Science Foundation of China (12022303), the China-Chile Joint Research Fund (CCJRF No. 1906), and the CAS Pioneer Hundred Talents Program. RPT thanks the CAS President’s International Fellowship Initiative (PIFI) (Grant No. E085201009) for supporting this work. We acknowledge the science research grants from the China Manned Space Project with No. CMS-CSST-2021-A04 and CMS-CSST-2021-A07. ACS acknowledges funding from the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) and the Rio Grande do Sul Research Foundation (FAPERGS) through grants CNPq-11153/2018-6, CNPq-314301/2021-6 and FAPERGS/CAPES 19/2551-0000696-9 and the Chinese Academy of Sciences (CAS) President’s International Fellowship Initiative (PIFI) through grant E085201009. R.P.T. and Z.Y.Z. thanks Shuairu Zhu, Fang-Ting Yuan, Ruqiu Lin, and Xiang Ji for their useful discussion during the preparations of the manuscript. R.P.T. acknowledges Carolina Queiroz for sharing information about the JPAS database. This paper has gone through the internal review by the J-PAS collaboration. Based on observations made with the JST/T250 telescope and JP Cam at the Observatorio Astrofísico de Javalambre (OAJ), in Teruel, owned, managed, and operated by the Centro de Estudios de Física del Cosmos de Aragón (CEFCA). We acknowledge the OAJ Data Processing and Archiving Unit (UPAD) for reducing and calibrating the OAJ data used in this work. Funding for the J-PAS Project has been provided by the Governments of Spain and Aragón through the Fondo de Inversión de Teruel, European FEDER funding and the Spanish Ministry of Science, Innovation and Universities, and by the Brazilian agencies FINEP, FAPESP, FAPERJ and by the National Observatory of Brazil. Additional funding was also provided by the Tartu Observatory and by the J-PAS Chinese Astronomical Consortium. L.A.D.G., C.K., and R.G.D., acknowledge financial support from the State Agency for Research of the Spanish MCIU through the “Center of Excellence Severo Ochoa” award to the Instituto de Astrofísica de Andalucía (SEV-2017-0709), and to PID2019-109067-GB100.
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20. Two temperate super-Earths transiting a nearby late-type M dwarf
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L. Delrez, C. A. Murray, F. J. Pozuelos, N. Narita, E. Ducrot, M. Timmermans, N. Watanabe, A. J. Burgasser, T. Hirano, B. V. Rackham, K. G. Stassun, V. Van Grootel, C. Aganze, M. Cointepas, S. Howell, L. Kaltenegger, P. Niraula, D. Sebastian, J. M. Almenara, K. Barkaoui, T. A. Baycroft, X. Bonfils, F. Bouchy, A. Burdanov, D. A. Caldwell, D. Charbonneau, D. R. Ciardi, K. A. Collins, T. Daylan, B.-O. Demory, J. de Wit, G. Dransfield, S. B. Fajardo-Acosta, M. Fausnaugh, A. Fukui, E. Furlan, L. J. Garcia, C. L. Gnilka, Y. Gómez Maqueo Chew, M. A. Gómez-Muñoz, M. N. Günther, H. Harakawa, K. Heng, M. J. Hooton, Y. Hori, M. Ikoma, E. Jehin, J. M. Jenkins, T. Kagetani, K. Kawauchi, T. Kimura, T. Kodama, T. Kotani, V. Krishnamurthy, T. Kudo, V. Kunovac, N. Kusakabe, D. W. Latham, C. Littlefield, J. McCormac, C. Melis, M. Mori, F. Murgas, E. Palle, P. P. Pedersen, D. Queloz, G. Ricker, L. Sabin, N. Schanche, U. Schroffenegger, S. Seager, B. Shiao, S. Sohy, M. R. Standing, M. Tamura, C. A. Theissen, S. J. Thompson, A. H. M. J. Triaud, R. Vanderspek, S. Vievard, R. D. Wells, J. N. Winn, Y. Zou, S. Zúñiga-Fernández, M. Gillon, Ministerio de Ciencia e Innovación (España), European Commission, European Research Council, Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), and Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France
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Earth and Planetary Astrophysics (astro-ph.EP) ,Stars: individual: SPECULOOS-2 ,[SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph] ,Stars: individual: TOI-4306 ,530 Physics ,520 Astronomy ,FOS: Physical sciences ,Astronomy and Astrophysics ,Planets and satellites: detection ,500 Science ,stars: individual: TIC 44898913 ,[SDU]Sciences of the Universe [physics] ,Space and Planetary Science ,Stars: individual: LP 890-9 ,Techniques: photometric ,Astrophysics - Earth and Planetary Astrophysics - Abstract
Full list of authors: Delrez, L.; Murray, C. A.; Pozuelos, F. J.; Narita, N.; Ducrot, E.; Timmermans, M.; Watanabe, N.; Burgasser, A. J.; Hirano, T.; Rackham, B., V; Stassun, K. G.; Van Grootel, V.; Aganze, C.; Cointepas, M.; Howell, S.; Kaltenegger, L.; Niraula, P.; Sebastian, D.; Almenara, J. M.; Barkaoui, K.; Baycroft, T. A.; Bonfils, X.; Bouchy, F.; Burdanov, A.; Caldwell, D. A.; Charbonneau, D.; Ciardi, D. R.; Collins, K. A.; Daylan, T.; Demory, B-O; Guenther, N.; de Wit, J.; Dransfield, G.; Fajardo-Acosta, S. B.; Fausnaugh, M.; Fukui, A.; Furlan, E.; Garcia, L. J.; Gnilka, C. L.; Chew, Y. Gomez Maqueo; Gomez-Munoz, M. A.; Harakawa, H.; Heng, K.; Hooton, M. J.; Hori, Y.; Ikoma, M.; Jehin, E.; Jenkins, J. M.; Kagetani, T.; Kawauchi, K.; Kimura, T.; Kodama, T.; Kotani, T.; Krishnamurthy, V; Kudo, T.; Kunovac, V; Kusakabe, N.; Latham, D. W.; Littlefield, C.; McCormac, J.; Melis, C.; Mori, M.; Murgas, F.; Palle, E.; Pedersen, P. P.; Queloz, D.; Ricker, G.; Sabin, L.; Schanche, N.; Schroffenegger, U.; Seager, S.; Shiao, B.; Sohy, S.; Standing, M. R.; Tamura, M.; Theissen, C. A.; Thompson, S. J.; Triaud, A. H. M. J.; Vanderspek, R.; Vievard, S.; Wells, R. D.; Winn, J. N.; Zou, Y.; Zuniga-Fernandez, S.; Gillon, M.--This is an Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited., Context. In the age of JWST, temperate terrestrial exoplanets transiting nearby late-type M dwarfs provide unique opportunities for characterising their atmospheres, as well as searching for biosignature gases. In this context, the benchmark TRAPPIST-1 planetary system has garnered the interest of a broad scientific community. Aims. We report here the discovery and validation of two temperate super-Earths transiting LP 890-9 (TOI-4306, SPECULOOS-2), a relatively low-activity nearby (32 pc) M6V star. The inner planet, LP 890-9 b, was first detected by TESS (and identified as TOI-4306.01) based on four sectors of data. Intensive photometric monitoring of the system with the SPECULOOS Southern Observatory then led to the discovery of a second outer transiting planet, LP 890-9 c (also identified as SPECULOOS-2 c), previously undetected by TESS. The orbital period of this second planet was later confirmed by MuSCAT3 follow-up observations. Methods. We first inferred the properties of the host star by analyzing its Lick/Kast optical and IRTF/SpeX near-infrared spectra, as well as its broadband spectral energy distribution, and Gaia parallax. We then derived the properties of the two planets by modelling multi-colour transit photometry from TESS, SPECULOOS-South, MuSCAT3, ExTrA, TRAPPIST-South, and SAINT-EX. Archival imaging, Gemini-South/Zorro high-resolution imaging, and Subaru/IRD radial velocities also support our planetary interpretation. Results. With a mass of 0.118 ± 0.002 M⊙, a radius of 0.1556 ± 0.0086 R⊙, and an effective temperature of 2850 ± 75 K, LP 890-9 is the second-coolest star found to host planets, after TRAPPIST-1. The inner planet has an orbital period of 2.73 d, a radius of 1.320 −0.027+0.053 R⊕, and receives an incident stellar flux of 4.09 ± 0.12 S⊕. The outer planet has a similar size of 1.367 −0.039+0.055R⊕ and an orbital period of 8.46 d. With an incident stellar flux of 0.906 ± 0.026 S⊕, it is located within the conservative habitable zone, very close to its inner limit (runaway greenhouse). Although the masses of the two planets remain to be measured, we estimated their potential for atmospheric characterisation via transmission spectroscopy using a mass-radius relationship and found that, after the TRAPPIST-1 planets, LP 890-9 c is the second-most favourable habitable-zone terrestrial planet known so far (assuming for this comparison a similar atmosphere for all planets). Conclusions. The discovery of this remarkable system offers another rare opportunity to study temperate terrestrial planets around our smallest and coolest neighbours. © L. Delrez et al. 2022., Funding for the TESS mission is provided by NASA’s Science Mission Directorate. We acknowledge the use of public TESS data from pipelines at the TESS Science Office and at the TESS Science Processing Operations Center. This research has made use of the Exoplanet Follow-up Observation Program website, which is operated by the California Institute of Technology, under contract with the National Aeronautics and Space Administration under the Exoplanet Exploration Program. Resources supporting this work were provided by the NASA High-End Computing (HEC) Program through the NASA Advanced Supercomputing (NAS) Division at Ames Research Center for the production of the SPOC data products. This paper includes data collected by the TESS mission that are publicly available from the Mikulski Archive for Space Telescopes (MAST). The research leading to these results has received funding from the European Research Council (ERC) under the FP/2007-2013 ERC grant agreement no 336480, and under the European Union’s Horizon 2020 research and innovation programme (grants agreements no 679030 & 803193/BEBOP); from an Action de Recherche Concertée (ARC) grant, financed by the Wallonia-Brussels Federation, from the Balzan Prize Foundation, from the BELSPO/BRAIN2.0 research program (PORTAL project), from the Science and Technology Facilities Council (STFC; grants no ST/S00193X/1, ST/00305/1, and ST/W000385/1), and from F.R.S-FNRS (Research Project ID T010920F). This work was also partially supported by a grant from the Simons Foundation (PI: Queloz, grant number 327127), as well as by the MERAC foundation (PI: Triaud). TRAPPIST is funded by the Belgian Fund for Scientific Research (Fond National de la Recherche Scientifique, FNRS) under the grant PDR T.0120.21, with the participation of the Swiss National Science Fundation (SNF). This work is partly supported by MEXT/JSPS KAKENHI Grant Numbers JP15H02063, JP17H04574, JP18H05439, JP18H05442, JP19K14783, JP21H00035, JP21K13975, JP21K20376, JP22000005, Grant-in-Aid for JSPS Fellows Grant Number JP20J21872, JST CREST Grant Number JPMJCR1761, the Astrobiology Center of National Institutes of Natural Sciences (NINS) (Grant Numbers AB031010, AB031014), and Social welfare juridical person SHIYUKAI (chairman MASAYUKI KAWASHIMA). This paper is based on data collected at the Subaru Telescope, which is located atop Maunakea and operated by the National Astronomical Observatory of Japan (NAOJ). We wish to recognise and acknowledge the very significant cultural role and reverence that the summit of Maunakea has always had within the indigenous Hawaiian community. This paper is based on observations made with the MuSCAT3 instrument, developed by the Astrobiology Center and under financial supports by JSPS KAKENHI (JP18H05439) and JST PRESTO (JPMJPR1775), at Faulkes Telescope North on Maui, HI, operated by the Las Cumbres Observatory. Some of the observations in the paper made use of the High-Resolution Imaging instrument Zorro obtained under Gemini LLP Proposal Number: GN/S-2021A-LP-105. Zorro was funded by the NASA Exoplanet Exploration Program and built at the NASA Ames Research Center by Steve B. Howell, Nic Scott, Elliott P. Horch, and Emmett Quigley. Zorro was mounted on the Gemini North (and/or South) telescope of the international Gemini Observatory, a program of NSF s OIR Lab, which is managed by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with the National Science Foundation on behalf of the Gemini partnership: the National Science Foundation (United States), National Research Council (Canada), Agencia Nacional de Investigación y Desarrollo (Chile), Ministerio de Ciencia, Tecnología e Innovación (Argentina), Ministério da Ciência, Tecnologia, Inovações e Comunicações (Brazil), and Korea Astronomy and Space Science Institute (Republic of Korea). We acknowledge funding from the European Research Council under the ERC Grant Agreement n. 3 37591-ExTrA. This work has been carried out within the framework of the NCCR PlanetS supported by the Swiss National Science Foundation. This work is based upon observations carried out at the Observatorio Astronómico Nacional at the Sierra de San Pedro Mártir (OAN-SPM), Baja California, México. We warmly thank the entire technical staff of the Observatorio Astronómico Nacional at San Pedro Mártir for their unfailing support to SAINT-EX operations. Research at Lick Observatory is partially supported by a generous gift from Google. L.D. is an F.R.S.-FNRS Postdoctoral Researcher. M.G. and E.J. are F.R.S.-FNRS Senior Research Associates. V.V.G. is an F.R.S.-FNRS Research Associate. B.V.R. thanks the Heising-Simons Foundation for support. Y.G.M.C. acknowledges support from UNAM-PAPIIT IG-101321. B.-O.D. acknowledges support from the Swiss National Science Foundation (PP00P2-163967 and PP00P2-190080). M.N.G. acknowledges support from the European Space Agency (ESA) as an ESA Research Fellow. A.H.M.J.T acknowledges funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement no 803193/BEBOP), from the MERAC foundation, and from the Science and Technology Facilities Council (STFC; grants no ST/S00193X/1, ST/00305/1, and ST/W000385/1). E.D. acknowledges support from the innovation and research Horizon 2020 program in the context of the Marie Sklodowska-Curie subvention 945298. V.K. acknowledges support from NSF award AST2009343. This publication benefits from the support of the French Community of Belgium in the context of the FRIA Doctoral Grant awarded to M.T., With funding from the Spanish government through the Severo Ochoa Centre of Excellence accreditation SEV-2017-0709.
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- 2022
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21. Tensor-to-scalar ratio forecasts for extended LiteBIRD frequency configurations
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U. Fuskeland, J. Aumont, R. Aurlien, C. Baccigalupi, A. J. Banday, H. K. Eriksen, J. Errard, R. T. Génova-Santos, T. Hasebe, J. Hubmayr, H. Imada, N. Krachmalnicof, L. Lamagna, G. Pisano, D. Poletti, M. Remazeilles, K. L. Thompson, L. Vache, I. K. Wehus, S. Azzoni, M. Ballardini, R. B. Barreiro, N. Bartolo, A. Basyrov, D. Beck, M. Bersanelli, M. Bortolami, M. Brilenkov, E. Calabrese, A. Carones, F. J. Casas, K. Cheung, J. Chluba, S. E. Clark, L. Clermont, and E.J. Wollack
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Space Sciences (General) - Abstract
LiteBIRD is a planned JAXA-led cosmic microwave background (CMB) B-mode satellite experiment aiming for launch in the late 2020s, with a primary goal of detecting the imprint of primordial inflationary gravitational waves. Its current baseline focal-plane configuration includes 15 frequency bands between 40 and 402 GHz, fulfilling the mission requirements to detect the amplitude of gravitational waves with the total uncertainty on the tensor-to-scalar ratio, δr, down to δr < 0.001. A key aspect of this performance is accurate astrophysical component separation, and the ability to remove polarized thermal dust emission is particularly important. In this paper we note that the CMB frequency spectrum falls off nearly exponentially above 300 GHz relative to the thermal dust spectral energy distribution, and a relatively minor high frequency extension can therefore result in even lower uncertainties and better model reconstructions. Specifically, we compared the baseline design with five extended configurations, while varying the underlying dust modeling, in each of which the High-Frequency Telescope (HFT) frequency range was shifted logarithmically toward higher frequencies, with an upper cutoff ranging between 400 and 600 GHz. In each case, we measured the tensor-to-scalar ratio r uncertainty and bias using both parametric and minimum-variance component-separation algorithms. When the thermal dust sky model includes a spatially varying spectral index and temperature, we find that the statistical uncertainty on r after foreground cleaning may be reduced by as much as 30–50% by extending the upper limit of the frequency range from 400 to 600 GHz, with most of the improvement already gained at 500 GHz. We also note that a broader frequency range leads to higher residuals when fitting an incorrect dust model, but also it is easier to discriminate between models through higher χ2 sensitivity. Even in the case in which the fitting procedure does not correspond to the underlying dust model in the sky, and when the highest frequency data cannot be modeled with sufficient fidelity and must be excluded from the analysis, the uncertainty on r increases by only about 5% for a 500 GHz configuration compared to the baseline.
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- 2023
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22. Spectroscopic Characterisation of Microlensing Events: Towards a New Interpretation of OGLE-2011-BLG-0417
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Santerne, A, Beaulieu, J.-P, Rojas Ayala, B, Boisse, I, Schlawin, E, Almenara, J.-M, Batista, V, Bennett, D, Diaz, R. F, Figueira, P, James, D. J, Herter, T, Lillo-Box, J, Marquette, J. B, Ranc, C, Santos, N. C, and Sousa, S. G
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Astrophysics - Abstract
The microlensing event OGLE-2011-BLG-0417 is an exceptionally bright lens binary that was predicted to present radial velocity variation at the level of several km s1. Pioneer radial velocity follow-up observations with the UVES spectrograph at the ESOVLT of this system clearly ruled out the large radial velocity variation, leaving a discrepancy between the observation and the prediction. In this paper, we further characterise the microlensing system by analysing its spectral energy distribution (SED) derived using the UVES spectrum and new observations with the ARCoIRIS (CTIO) near-infrared spectrograph and the Keck adaptive optics instrumentNIRC2 in the J, H, and Ks-bands. We determine the mass and distance of the stars independently from the microlensing modelling. We find that the SED is compatible with a giant star in the Galactic bulge and a foreground star with a mass of 0.94 +/- 0.09 M solar mass at a distance of 1.07 +/- 0.24 kpc. We find that this foreground star is likely the lens. Its parameters are not compatible with the onespreviously reported in the literature (0.52 +/- 0.04 M solar mass at 0.95 +/- 0.06 kpc), based on the microlensing light curve. A thoughtful reanalysis of the microlensing event is mandatory to fully understand the reason of this new discrepancy. More importantly, this paper demonstrates that spectroscopic follow-up observations of microlensing events are possible and provide independent constraints on the parameters of the lens and source stars, hence breaking some degeneracies in the analysis. UV-to-NIR low-resolution spectrographs like X-shooter (ESOVLT) could substantially contribute to this follow-up efforts, with magnitude limits above all microlensing events detected so far.
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- 2016
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23. Incidence of Debris Discs Around FGK Stars in the Solar Neighbourhood
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Montesinos, B, Eiroa, C, Krivov, A. V, Marshall, J. P, Pilbratt, G. L, Liseau, R, Mora, A, Maldonado, J, Wolf, S, Ertel, S, Bayo, A, Augereau, J.-C, Heras, A. M, Fridlund, M, and Danchi, W. C
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Astrophysics ,Statistics And Probability - Abstract
Context. Debris discs are a consequence of the planet formation process and constitute the fingerprints of planetesimal systems. Their counterparts in the solar system are the asteroid and Edgeworth-Kuiper belts. Aims. The aim of this paper is to provide robust numbers for the incidence of debris discs around FGK stars in the solar neighborhood. Methods. The full sample of 177 FGK stars with d approx. less than 20 pc proposed for the DUst around NEarby Stars (DUNES) survey is presented. Herschel/PACS observations at 100 and 160 micrometers were obtained, and were complemented in some cases with data at 70 micrometers and at 250, 350, and 500 micrometer SPIRE photometry. The 123 objects observed by the DUNES collaboration were presented in a previous paper. The remaining 54 stars, shared with the Disc Emission via a Bias-free Reconnaissance in IR and Sub-mm (DEBRIS) consortium and observed by them, and the combined full sample are studied in this paper. The incidence of debris discs per spectral type is analyzed and put into context together with other parameters of the sample, like metallicity, rotation and activity, and age. Results. The subsample of 105 stars with d approx. less than 15 pc containing 23 F, 33 G, and 49 K stars is complete for F stars, almost complete for G stars, and contains a substantial number of K stars from which we draw solid conclusions on objects of this spectral type. The incidence rates of debris discs per spectral type are 0.26(+0.21/-0.14) (6 objects with excesses out of 23 F stars), 0.21(+0.17/-0.11) (7 out of 33 G stars), and 0.20(+0.14/-0.09) (10 out of 49 K stars); the fraction for all three spectral types together is 0.22(+0.08/-0.07) (23 out of 105 stars).The uncertainties correspond to a 95 confidence level. The medians of the upper limits of L(sub dust)/L(sub *) for each spectral type are 7.8 x 10(exp -7) (F), 1.4 x 10(exp -6) (G), and 2.2 x 10(exp -6) (K); the lowest values are around 4.0 x 10(exp -7). The incidence of debris discs is similar for active (young) and inactive (old) stars. The fractional luminosity tends to drop with increasing age, as expected from collisional erosion of the debris belts.
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- 2016
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24. The XXL Survey I. Scientific Motivations - Xmm-Newton Observing Plan - Follow-up Observations and Simulation Programme
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Pierre, M, Pacaud, F, Adami, C, Alis, S, Altieri, B, Baran, N, Benoist, C, Birkinshaw, M, Bongiorno, A, Bremer, M. N, Brusa, M, Butler, A, Ciliegi, P, Chiappetti, L, Clerc, N, Corasaniti, P. S, Coupon, J, De Breuck, C, Democles, J, Desai, S, Delhaize, J, Devriendt, J, Dubois, Y, Snowden, Steven L, and Eckert, D
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Astrophysics - Abstract
The quest for the cosmological parameters that describe our universe continues to motivate the scientific community to undertake very large survey initiatives across the electromagnetic spectrum. Over the past two decades, the Chandra and XMM-Newton observatories have supported numerous studies of X-ray-selected clusters of galaxies, active galactic nuclei (AGNs), and the X-ray background. The present paper is the first in a series reporting results of the XXL-XMM survey; it comes at a time when the Planck mission results are being finalized. Aims. We present the XXL Survey, the largest XMM programme totaling some 6.9 Ms to date and involving an international consortium of roughly 100 members. The XXL Survey covers two extragalactic areas of 25 deg2 each at a point-source sensitivity of approx. 5 x 10(exp 15) erg/s/sq cm in the [0.5-2] keV band (completeness limit). The surveys main goals are to provide constraints on the dark energy equation of state from the space-time-distribution of clusters of galaxies and to serve as a pathfinder for future, wide-area X-ray missions. We review science objectives, including cluster studies, AGN evolution, and large-scale structure, that are being conducted with the support of approximately 30 follow-up programs. Methods. We describe the 542 XMM observations along with the associated multi- and numerical simulation programmes. We give a detailed account of the X-ray processing steps and describe innovative tools being developed for the cosmological analysis. Results. The paper provides a thorough evaluation of the X-ray data, including quality controls, photon statistics, exposure and background maps, and sky coverage. Source catalogue construction and multi-associations are briefly described. This material will be the basis for the calculation of the cluster and AGN selection functions, critical elements of the cosmological and science analyses. Conclusions. The XXL multi- data set will have a unique lasting legacy value for cosmological and extragalactic studies and will serve asa calibration resource for future dark energy studies with clusters and other X-ray selected sources. With the present article, we release the XMM XXL photon and smoothed images along with the corresponding exposure maps.
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- 2016
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25. The Calern Asteroid Polarisation Survey
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Ph. Bendjoya, A. Cellino, J.-P. Rivet, M. Devogèle, S. Bagnulo, L. Abe, D. Vernet, R. Gil-Hutton, and A. Veneziani
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Space and Planetary Science ,Astronomy and Astrophysics - Abstract
Context. The Calern Asteroid Polarimetric Survey (CAPS), a collaboration between the INAF Astrophysical Observatory of Torino (Italy) and the Observatoire de la Côte d’Azur (Nice, France), has produced new asteroid polarimetric data for a number of years, and is one of the most important, currently active projects of asteroid polarimetry. Aims. The purpose of this paper is to make public the CAPS data collected thus far, to explain the adopted techniques of data reduction and computation of phase-polarisation curves for the measured objects, and explain, by means of some examples, the importance of the CAPS database. Methods. The pipeline of data reduction has been recently updated and made as automatic as possible, using numerical algorithms developed specifically for the purposes of CAPS. The derivation of phase-polarisation curves for the observed asteroids is done using established criteria and algorithms that have recently been slightly improved, and are also summarised in this paper. Results. The CAPS catalogue is a steadily growing source of information which can be exploited for different purposes, including, but not limited to, an updated calibration of the relations existing between different polarimetric parameters and the geometric albedo of the objects, and a study of classes of objects that can be most easily identified by means of their polarimetric properties. These subjects will be more specifically discussed in separate papers. Conclusions. Asteroid polarimetry data nicely complement the results of other more commonly used techniques, including visible and IR photometry and spectroscopy. CAPS contains a lot of much-desired information about physical properties, which can hardly be inferred by means of other techniques.
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- 2022
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26. The faintest solar coronal hard X-rays observed with FOXSI
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Juan Camilo Buitrago-Casas, Lindsay Glesener, Steven Christe, Säm Krucker, Juliana Vievering, P. S. Athiray, Sophie Musset, Lance Davis, Sasha Courtade, Gregory Dalton, Paul Turin, Zoe Turin, Brian Ramsey, Stephen Bongiorno, Daniel Ryan, Tadayuki Takahashi, Kento Furukawa, Shin Watanabe, Noriyuki Narukage, Shin-nosuke Ishikawa, Ikuyuki Mitsuishi, Kouichi Hagino, Van Shourt, Jessie Duncan, Yixian Zhang, and Stuart D. Bale
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High Energy Astrophysical Phenomena (astro-ph.HE) ,Astrophysics - Solar and Stellar Astrophysics ,Space and Planetary Science ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics - High Energy Astrophysical Phenomena ,Astrophysics - Instrumentation and Methods for Astrophysics ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,Solar and Stellar Astrophysics (astro-ph.SR) - Abstract
Context. Solar nanoflares are small impulsive events releasing magnetic energy in the corona. If nanoflares follow the same physics as their larger counterparts, they should emit hard X-rays (HXRs) but with a rather faint intensity. A copious and continuous presence of nanoflares would result in a sustained HXR emission. These nanoflares could deliver enormous amounts of energy into the solar corona, possibly accounting for its high temperatures. To date, there has not been any direct observation of such persistent HXRs from the quiescent Sun. However, the quiet-Sun HXR emission was constrained in 2010 using almost 12 days of quiescent solar off-pointing observations by the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI). These observations set 2σ upper limits at 3.4 × 10−2 photons s−1 cm−2 keV−1 and 9.5 × 10−4 photons s−1 cm−2 keV−1 for the 3–6 keV and 6–12 keV energy ranges, respectively. Aims. Observing faint HXR emission is challenging because it demands high sensitivity and dynamic range instruments. The Focusing Optics X-ray Solar Imager (FOXSI) sounding rocket experiment excels in these two attributes when compared with RHESSI. FOXSI completed its second and third successful flights (FOXSI-2 and -3) on December 11, 2014, and September 7, 2018, respectively. This paper aims to constrain the quiet-Sun emission in the 5–10 keV energy range using FOXSI-2 and -3 observations. Methods. To fully characterize the sensitivity of FOXSI, we assessed ghost ray backgrounds generated by sources outside of the field of view via a ray-tracing algorithm. We used a Bayesian approach to provide upper thresholds of quiet-Sun HXR emission and probability distributions for the expected flux when a quiet-Sun HXR source is assumed to exist. Results. We found a FOXSI-2 upper limit of 4.5 × 10−2 photons s−1 cm−2 keV−1 with a 2σ confidence level in the 5–10 keV energy range. This limit is the first-ever quiet-Sun upper threshold in HXR reported using ∼1 min observations during a period of high solar activity. RHESSI was unable to measure the quiet-Sun emission during active times due to its limited dynamic range. During the FOXSI-3 flight, the Sun exhibited a fairly quiet configuration, displaying only one aged nonflaring active region. Using the entire ∼6.5 min of FOXSI-3 data, we report a 2σ upper limit of ∼10−4 photons s−1 cm−2 keV−1 for the 5–10 keV energy range. Conclusions. The FOXSI-3 upper limits on quiet-Sun emission are similar to that previously reported, but FOXSI-3 achieved these results with only 5 min of observations or about 1/2600 less time than RHESSI. A possible future spacecraft using hard X-ray focusing optics like those in the FOXSI concept would allow enough observation time to constrain the current HXR quiet-Sun limits further, or perhaps even make direct detections. This is the first report of quiet-Sun HXR limits from FOXSI and the first science paper using FOXSI-3 observations.
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- 2022
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27. Substructure in the stellar halo near the Sun
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Lövdal, S. S., Ruiz-Lara, T., Koppelman, H. H., Matsuno, T., Dodd, E., Helmi, A., Kapteyn Astronomical Institute, and Astronomy
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Galaxy: evolution ,Solar neighborhood ,Galaxy: formation ,Methods: data analysis ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Galaxy: kinematics and dynamics ,Astrophysics::Galaxy Astrophysics ,Galaxy: halo - Abstract
Aims: Develop a data-driven and statistically based method for finding such clumps in Integrals of Motion space for nearby halo stars and evaluating their significance robustly. Methods: We use data from Gaia EDR3 extended with radial velocities from ground-based spectroscopic surveys to construct a sample of halo stars within 2.5 kpc from the Sun. We apply a hierarchical clustering method that uses the single linkage algorithm in a 3D space defined by the commonly used integrals of motion energy $E$, together with two components of the angular momentum, $L_z$ and $L_\perp$. To evaluate the statistical significance of the clusters found, we compare the density within an ellipsoidal region centered on the cluster to that of random sets with similar global dynamical properties. We pick out the signal at the location of their maximum statistical significance in the hierarchical tree. We estimate the proximity of a star to the cluster center using the Mahalanobis distance. We also apply the HDBSCAN clustering algorithm in velocity space. Results: Our procedure identifies 67 highly significant clusters ($ > 3\sigma$), containing 12\% of the sources in our halo set, and in total 232 subgroups or individual streams in velocity space. In total, 13.8\% of the stars in our data set can be confidently associated to a significant cluster based on their Mahalanobis distance. Inspection of our data set reveals a complex web of relationships between the significant clusters, suggesting that they can be tentatively grouped into at least 6 main structures, many of which can be associated to previously identified halo substructures, and a number of independent substructures. This preliminary conclusion is further explored in an accompanying paper by Ruiz-Lara et al., where we also characterize the substructures in terms of their stellar populations. Conclusions: We find... (abridged version), Comment: 16 pages, 14 figures, 2 tables. Accepted for publication in A&A. This is the first in a series of papers, the second (Ruiz-Lara et al.) can be found in https://ui.adsabs.harvard.edu/abs/2022arXiv220102405R/abstract Code of the clustering algorithm can be found in https://github.com/SofieLovdal/IOM_clustering
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- 2022
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28. Coupling between turbulence and solar-like oscillations: A combined Lagrangian PDF/SPH approach
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J. Philidet, K. Belkacem, and M.-J. Goupil
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Plasma Physics (physics.plasm-ph) ,Astrophysics - Solar and Stellar Astrophysics ,Space and Planetary Science ,Fluid Dynamics (physics.flu-dyn) ,FOS: Physical sciences ,Astronomy and Astrophysics ,Physics - Fluid Dynamics ,Solar and Stellar Astrophysics (astro-ph.SR) ,Physics - Plasma Physics - Abstract
The first paper of this series established a linear stochastic wave equation for solar-like p-modes, correctly taking the effect of turbulence thereon into account. In this second paper, we aim at deriving simultaneous expressions for the excitation rate, damping rate, and modal surface effect associated with any given p-mode, as an explicit function of the statistical properties of the turbulent velocity field. We reduce the stochastic wave equation to complex amplitude equations for the normal oscillating modes of the system. We then derive the equivalent Fokker-Planck equation for the real amplitudes and phases of all the oscillating modes of the system simultaneously. The effect of the finite-memory time of the turbulent fluctuations (comparable to the period of the modes) on the modes themselves is consistently and rigorously accounted for, by means of the simplified amplitude equation formalism. This formalism accounts for mutual linear mode coupling in full, and we then turn to the special single-mode case. This allows us to derive evolution equations for the mean energy and mean phase of each mode, from which the excitation rate, the damping rate, and the modal surface effect naturally arise. We show that the expression for the excitation rate of the modes is identical to previous results obtained through a different modelling approach, thus supporting the validity of the formalism presented here. We also recover the fact that the damping rate and modal surface effect correspond to the real and imaginary part of the same single complex quantity. We explicitly separate the different physical contributions to these observables, in particular the turbulent pressure contribution and the joint effect of the pressure-rate-of-strain correlation and the turbulent dissipation. We show that the former dominates for high-frequency modes and the latter for low-frequency modes., Accepted for publication in A&A. 23 pages, 2 figures
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- 2022
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29. A search for transiting planets around hot subdwarfs
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A. Thuillier, V. Van Grootel, M. Dévora-Pajares, F. J. Pozuelos, S. Charpinet, and L. Siess
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Planet-star interactions ,Earth and Planetary Astrophysics (astro-ph.EP) ,Planetary systems ,Astrophysics - Solar and Stellar Astrophysics ,Space and Planetary Science ,horizontal-branch [Stars] ,photometric [Techniques] ,Subdwarfs ,FOS: Physical sciences ,Astronomy and Astrophysics ,Solar and Stellar Astrophysics (astro-ph.SR) ,Astrophysics - Earth and Planetary Astrophysics - Abstract
Acknowledgements. We warmly thank the anonymous referee for constructive remarks that improved our paper. We thank Uli Heber and Elizabeth M. Green for their help on the characterisation of several of our targets, as well as attendees of the sdOB9.5 conference in Potsdam, namely but not limited to, Stephan Geier and Philipp Podsiadlowksi, as the discussion there were of great interest for this work. This work has been supported by the University of Liège through an ARC grant for Concerted Research Actions financed by the Wallonia-Brussels Federation. A.T. acknowledge financial support from the ULB “Fond de rattrapage PDR”. V.V.G. and L.S are senior F.R.S.-FNRS Research Associates. S.C. acknowledges financial support from the Centre National d’Études Spatiales (CNES, France). This paper includes data collected by the TESS mission. Funding for the TESS mission is provided by the NASA Explorer Program. Funding for the TESS Asteroseismic Science Operations Centre is provided by the Danish National Research Foundation (Grant agreement no.: DNRF106), ESA PRODEX (PEA 4000119301) and Stellar Astrophysics Centre (SAC) at Aarhus University. We thank the TESS team and staff and TASC/TASOC for their support of the present work. This work has made use of data from the ESA mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/ gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement., Context. Hot subdwarfs, which are hot and small He-burning objects, are ideal targets for exploring the evolution of planetary systems after the red giant branch (RGB). Thus far, no planets have been confirmed around them, and no systematic survey to find planets has been carried out. Aims. In this project, we aim to perform a systematic transit survey in all light curves of hot subdwarfs from space-based telescopes (Kepler, K2, TESS, and CHEOPS). The goal is to compute meaningful statistics on two points: firstly, the occurrence rates of planets around hot subdwarfs, and secondly, the probability of survival for close-in planets engulfed during the RGB phase of their host. This paper focuses on the analysis of the observations carried out during cycle 1 of the TESS mission. Methods. We used our specifically designed pipeline SHERLOCK to search for transits in the available light curves. When a signal is detected, it is processed in the next evaluating stages before an object is qualified for follow-up observations and in-depth analysis to determine the nature of the transiting body. Results. We applied our method to the 792 hot subdwarfs observed during cycle 1 of TESS. While 378 interesting signals were detected in the light curves, only 26 stars were assigned for follow-up observations. We have identified a series of eclipsing binaries, transiting white dwarfs, and other types of false positives, but no planet has been confirmed thus far. A first computation of the upper limit for occurrence rates was made with the 549 targets displaying no signal. Conclusions. The tools and method we developed proved their efficiency in analysing the available light curves from space missions, from detecting an interesting signal to identifying a transiting planet. This will allow us to fulfil the two main goals of this project., Aarhus Universitet, Australian Research Council, Danmarks Grundforskningsfond DNRF106, ESA PEA 4000119301, Wallonia-Brussels Federation, National Aeronautics and Space Administration, Centre National d’Etudes Spatiales, Université de Liège
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- 2022
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30. Identifying quiescent compact objects in massive Galactic single-lined spectroscopic binaries
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L. Mahy, H. Sana, T. Shenar, K. Sen, N. Langer, P. Marchant, M. Abdul-Masih, G. Banyard, J. Bodensteiner, D. M. Bowman, K. Dsilva, M. Fabry, C. Hawcroft, S. Janssens, T. Van Reeth, C. Eldridge, and Low Energy Astrophysics (API, FNWI)
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High Energy Astrophysical Phenomena (astro-ph.HE) ,Astrophysics - Solar and Stellar Astrophysics ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,Astrophysics::Solar and Stellar Astrophysics ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics - High Energy Astrophysical Phenomena ,Astrophysics - Astrophysics of Galaxies ,Astrophysics::Galaxy Astrophysics ,Solar and Stellar Astrophysics (astro-ph.SR) - Abstract
Aims. To search for these rare objects, we study 32 Galactic O-type stars that were reported as SB1s in the literature. In our sample we include Cyg X-1, which is known to host an accreting stellar-mass BH, and HD 74194, a supergiant fast X-ray transient, in order to validate our methodology. The final goal is to characterise the nature of the unseen companions to determine if they are MS stars, stripped helium stars, triples, or compact objects such as neutron stars or stellar-mass BHs. Methods. After measuring radial velocities and deriving orbital solutions for all the systems in our sample, we performed spectral disentangling to extract putative signatures of faint secondary companions from the composite spectra. We derived stellar parameters for the visible stars and estimated the mass ranges of the secondary stars using the binary mass function. Variability observed in the photometric TESS light curves was also searched for indications of the presence of putative companions, degenerate or not. Results. In 17 of the 32 systems reported as SB1s, we extract secondary signatures, down to mass ratios of ~0.15. For the 17 newly detected double-lined spectroscopic binaries (SB2s), we derive physical properties of the individual components and discuss why they have not been detected as such before. Among the remaining systems, we identify nine systems with possible NS or low-mass MS companions. For Cyg X-1 and HD 130298, we are not able to extract any signatures for the companions, and the minimum masses of their companions are estimated to be about 7Msun. Our simulations show that secondaries with such a mass should be detectable from our dataset, no matter their nature: MS stars, stripped helium stars or even triples. While this is expected for Cyg X-1, confirming our methodology, our simulations also strongly suggest that HD 130298 could be another candidate to host a stellar-mass BH., 20 pages (31 pages of Appendix), 19 figures, A&A in press. The abstract is shorter than in the paper, and some figures, and tables have been cut in the paper
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- 2022
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31. XMM-Newton and Swift observations of supergiant high mass X-ray binaries
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C. Ferrigno, E. Bozzo, and P. Romano
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High Energy Astrophysical Phenomena (astro-ph.HE) ,Space and Planetary Science ,Astrophysics::High Energy Astrophysical Phenomena ,FOS: Physical sciences ,Astrophysics::Solar and Stellar Astrophysics ,Astronomy and Astrophysics ,Astrophysics - High Energy Astrophysical Phenomena - Abstract
Wind-fed supergiant X-ray binaries are precious laboratories not only to study accretion under extreme gravity and magnetic field conditions, but also to probe still highly debated properties of massive star winds. These includes the so-called clumps, originated from the inherent instability of line driven winds, and larger structures. In this paper, we report on the results of the last (and not yet published) monitoring campaigns that our group has been carrying out since 2007 with both XMM-Newton and the Swift Neil Gehrels observatory. Data collected with the EPIC cameras on-board XMM-Newton allow us to carry out a detailed hardness ratio-resolved spectral analysis that can be used as an efficient way to detect spectral variations associated to the presence of clumps. Long-term observations with the XRT on-board Swift, evenly sampling the X-ray emission of supergiant X-ray binaries over many different orbital cycles, are exploited to look for the presence of large scale structures in the medium surrounding the compact objects. The results reported in this paper represent the outcomes of the concluded observational campaigns we carried out on the supergiant X-ray binaries 4U 1907+09, IGR J16393-4643, IGR J19140+0951, and XTE J1855-026, as well as the supergiant fast X-ray transients IGR J17503-2636, IGR J18410-0535, and IGR J11215-5952. All results are discussed in the context of wind-fed supergiant X-ray binaries and shall ideally serve to optimally shape the next observational campaigns aimed at sources in the same classes. We show in one of the paper appendices that IGR J17315-3221, preliminary classified in the literature as a possible supergiant X-ray binary discovered by INTEGRAL, is the product of a data analysis artifact and should thus be disregarded for future studies., Accepted for publication in Astronomy & Astrophysics
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- 2022
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32. A mini-chemical scheme with net reactions for 3D general circulation models
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Shang-Min Tsai, Elspeth K. H. Lee, and Raymond Pierrehumbert
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Space and Planetary Science ,Astronomy and Astrophysics - Abstract
Context. Growing evidence has indicated that the global composition distribution plays an indisputable role in interpreting observational data. Three-dimensional general circulation models (GCMs) with a reliable treatment of chemistry and clouds are particularly crucial in preparing for upcoming observations. In attempts to achieve 3D chemistry-climate modeling, the challenge mainly lies in the expensive computing power required for treating a large number of chemical species and reactions. Aims. Motivated by the need for a robust and computationally efficient chemical scheme, we devise a mini-chemical network with a minimal number of species and reactions for H2-dominated atmospheres. Methods. We apply a novel technique to simplify the chemical network from a full kinetics model, VULCAN, by replacing a large number of intermediate reactions with net reactions. The number of chemical species is cut down from 67 to 12, with the major species of thermal and observational importance retained, including H2O, CH4, CO, CO2, C2H2, NH3, and HCN. The size of the total reactions is also greatly reduced, from ~800 to 20. We validated the mini-chemical scheme by verifying the temporal evolution and benchmarking the predicted compositions in four exoplanet atmospheres (GJ 1214b, GJ 436b, HD 189733b, and HD 209458b) against the full kinetics of VULCAN. Results. The mini-network reproduces the chemical timescales and composition distributions of the full kinetics well within an order of magnitude for the major species in the pressure range of 1 bar–0.1 mbar across various metallicities and carbon-to-oxygen (C/O) ratios. Conclusions. We have developed and validated a mini-chemical scheme using net reactions to significantly simplify a large chemical network. The small scale of the mini-chemical scheme permits simple use and fast computation, which is optimal for implementation in a 3D GCM or a retrieval framework. We focus on the thermochemical kinetics of net reactions in this paper and address photochemistry in a follow-up paper.
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- 2022
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33. KiDS-1000 cosmology: Cosmic shear constraints and comparison between two point statistics
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Hendrik Hildebrandt, Fabian Köhlinger, Konrad Kuijken, Benjamin Giblin, Maciej Bilicki, Thomas Erben, Henk Hoekstra, Huanyuan Shan, Chieh-An Lin, Benjamin Stölzner, Tilman Tröster, Fedor Getman, Jelte T. A. de Jong, Jan Luca van den Busch, Lance Miller, Catherine Heymans, Marika Asgari, Chris Blake, Arun Kannawadi, Peter Schneider, Andrej Dvornik, Benjamin Joachimi, Angus H. Wright, Mario Radovich, Edwin A. Valentijn, and Astronomy
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Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,CFHTLENS ,POWER SPECTRUM ,PARAMETER CONSTRAINTS ,Cosmic microwave background ,FOS: Physical sciences ,Lambda-CDM model ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Cosmology ,Bin ,Photometry (optics) ,symbols.namesake ,gravitational lensing: weak ,0103 physical sciences ,Statistics ,Methods ,DARK-MATTER ,Planck ,cosmological parameters ,010303 astronomy & astrophysics ,Observational ,ESTIMATORS ,Observations ,Physics ,Gravitational Lensing ,COSMIC cancer database ,010308 nuclear & particles physics ,Astronomy and Astrophysics ,GALAXIES ,MODEL ,CHALLENGE LIGHTCONE SIMULATION ,Gravitational lens ,Space and Planetary Science ,cosmology: observations ,symbols ,astro-ph.CO ,KIDS-450 ,large-scale structure of Universe ,methods: observational ,WEAK ,Cosmology and Nongalactic Astrophysics ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We present cosmological constraints from a cosmic shear analysis of the fourth data release of the Kilo-Degree Survey (KiDS-1000), doubling the survey area with nine-band optical and near-infrared photometry with respect to previous KiDS analyses. Adopting a spatially flat $\Lambda$CDM model, we find $S_8 = \sigma_8 (\Omega_{\rm m}/0.3)^{0.5} = 0.759^{+0.024}_{-0.021}$ for our fiducial analysis, which is in $3\sigma$ tension with the prediction of the Planck Legacy analysis of the cosmic microwave background. We compare our fiducial COSEBIs (Complete Orthogonal Sets of E/B-Integrals) analysis with complementary analyses of the two-point shear correlation function and band power spectra, finding results to be in excellent agreement. We investigate the sensitivity of all three statistics to a number of measurement, astrophysical, and modelling systematics, finding our $S_8$ constraints to be robust and dominated by statistical errors. Our cosmological analysis of different divisions of the data pass the Bayesian internal consistency tests, with the exception of the second tomographic bin. As this bin encompasses low redshift galaxies, carrying insignificant levels of cosmological information, we find that our results are unchanged by the inclusion or exclusion of this sample., Comment: 33 pages, 14 figures, 7 tables, Accepted to be published in A&A. This paper is part of the KiDS-1000 series of papers: Heymans, Tr\"oster et al. (arXiv:2007.15632), Hildebrandt et al. (arXiv:2007.15635), Joachimi et al. (arXiv:2007.01844) and Giblin et al. (arXiv:2007.01845). Online KiDS-1000 talks can be viewed at http://kids.strw.leidenuniv.nl/KiDS-1000.php or the KiDS Consortium youtube page
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- 2021
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34. A large sub-Neptune transiting the thick-disk M4V TOI-2406
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Daniel Apai, H. Riesgo, Jon M. Jenkins, A. Schroeder, Khalid Barkaoui, George R. Ricker, Amaury H. M. J. Triaud, Aidan Gibbs, Tansu Daylan, Wen Ping Chen, R. Petrucci, Alex Bixel, K. Hesse, C. Murray, Keivan G. Stassun, Valérie Van Grootel, Sara Seager, Maximilian N. Günther, Laetitia Delrez, A. Burdanov, Laurence Sabin, Elise Furlan, Jennifer Dietrich, G. Melgoza, Lionel Garcia, Paul Gabor, Elsa Ducrot, Richard P. Schwarz, C. Gnilka, P. P. Pedersen, B.-O. Demory, R. Gore, M. A. Gómez-Muñoz, Prajwal Niraula, Didier Queloz, K. Lester, Y. Gómez Maqueo Chew, Karen A. Collins, Tianjun Gan, U. Schroffenegger, J. D. Twicken, I. Plauchu-Frayn, Carlos Guerrero, Michael Fausnaugh, P. F. Guillén, H. Serrano, R. D. Wells, Natalia Guerrero, N. Schanche, N. Scott, Mathilde Timmermans, C. A. Theissen, Steve B. Howell, Francisco J. Pozuelos, A. Landa, Samantha Thompson, Joshua N. Winn, James McCormac, Georgina Dransfield, Michaël Gillon, Emmanuel Jehin, R. Burn, S. Giacalone, M. Dévora-Pajares, Th. Henning, Adam J. Burgasser, J. de Wit, D. Sebastian, Mourad Ghachoui, F. Montalvo, D. W. Latham, D. R. Rodriguez, P. Chinchilla, and Benjamin V. Rackham
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Dwarf star ,010504 meteorology & atmospheric sciences ,Population ,FOS: Physical sciences ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,individual: TOI-2406 [Stars] ,Neptune ,Planet ,0103 physical sciences ,Thick disk ,Astrophysics::Solar and Stellar Astrophysics ,education ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,0105 earth and related environmental sciences ,Physics ,Earth and Planetary Astrophysics (astro-ph.EP) ,education.field_of_study ,520 Astronomy ,photometric [Techniques] ,Astronomy and Astrophysics ,Exoplanet ,Radial velocity ,detection [Planets and satellites] ,Space and Planetary Science ,Astrophysics::Earth and Planetary Astrophysics ,Planetary mass ,Astrophysics - Earth and Planetary Astrophysics - Abstract
We thank the anonymous referee for their corrections and help in improving the paper. We warmly thank the entire technical staff of the Observatorio Astronomico Nacional at San Pedro Martir in Mexico for their unfailing support to SAINT-EX operations, namely: E. Cadena, T. Calvario, E. Colorado, B. Garcia, G. Guisa, A. Franco, L. Figueroa, B. Hernandez, J. Herrera, E. Lopez, E. Lugo, B. Martinez, J. M. Nunez, J. L. Ochoa, M. Pereyra, F. Quiroz, T. Verdugo, I. Zavala. B.V.R. thanks the Heising-Simons Foundation for support. Y.G.M.C acknowledges support from UNAM-PAPIIT IG-101321. B.-O. D. acknowledges support from the Swiss National Science Foundation (PP00P2-163967 and PP00P2-190080). R.B. acknowledges the support from the Swiss National Science Foundation under grant P2BEP2_195285. M.N.G. acknowledges support from MIT's Kavli Institute as a Juan Carlos Torres Fellow. A.H.M.J.T acknowledges funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement nffi 803193/BEBOP), from the MERAC foundation, and from the Science and Technology Facilities Council (STFC; grant nffi ST/S00193X/1). T.D. acknowledges support from MIT's Kavli Institute as a Kavli postdoctoral fellow Part of this work received support from the National Centre for Competence in Research PlanetS, supported by the Swiss National Science Foundation (SNSF). The research leading to these results has received funding from the ARC grant for Concerted Research Actions, financed by the Wallonia-Brussels Federation. TRAPPIST is funded by the Belgian Fund for Scientific Research (Fond National de la Recherche Scientifique, FNRS) under the grant FRFC 2.5.594.09.F, with the participation of the Swiss National Science Fundation (SNF). M.G. and E.J. are F.R.S.-FNRS Senior Research Associate. This publication benefits from the support of the French Community of Belgium in the context of the FRIA Doctoral Grant awarded to MT. We acknowledge the use of public TESS data from pipelines at the TESS Science Office and at the TESS Science Processing Operations Center. We acknowledge the use of public TESS Alert data from pipelines at the TESS Science Office and at the TESS Science Processing Operations Center. Resources supporting this work were provided by the NASA High-End Computing (HEC) Program through the NASA Advanced Supercomputing (NAS) Division at Ames Research Center for the production of the SPOC data products. Funding for the TESS mission is provided by NASA's Science Mission Directorate. This research has made use of the Exoplanet Follow-up Observation Program website, which is operated by the California Institute of Technology, under contract with the National Aeronautics and Space Administration under the Exoplanet Exploration Program. This paper includes data collected by the TESS mission that are publicly available from the Mikulski Archive for Space Telescopes (MAST). We thank the TESS GI program G03274 PI, Ryan Cloutier, for proposing the target of this work for 2-min-cadence observations in Sector 30. This work is based upon observations carried out at the Observatorio Astronomico Nacional on the Sierra de San Pedro Martir (OAN-SPM), Baja California, Mexico. This work makes use of observations from the LCOGT network. Part of the LCOGT telescope time was granted by NOIRLab through the Mid-Scale Innovations Program (MSIP). MSIP is funded by NSF. This work includes data collected at the Vatican Advanced Technology Telescope (VATT) on Mt. Graham. This paper includes data taken on the EDEN telescope network. We acknowledge support from the Earths in Other Solar Systems Project (EOS) and Alien Earths (grant numbers NNX15AD94G and 80NSSC21K0593), sponsored by NASA. Some of the observations in the paper made use of the High-Resolution Imaging instrument Zorro (Gemini program GS-2020B-LP-105). Zorro was funded by the NASA Exoplanet Exploration Program and built at the NASA Ames Research Center by Steve B. Howell, Nic Scott, Elliott P. Horch, and Emmett Quigley. Zorro was mounted on the Gemini South telescope of the international Gemini Observatory, a program of NSF's OIR Lab, which is managed by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with the National Science Foundation. on behalf of the Gemini partnership: the National Science Foundation (United States), National Research Council (Canada), Agencia Nacional de Investigacion y Desarrollo (Chile), Ministerio de Ciencia, Tecnologia e Innovacion (Argentina), Ministerio da Ciencia, Tecnologia, Inovacoes e Comunicacoes (Brazil), and Korea Astronomy and Space Science Institute (Republic of Korea). This research has made use of the NASA Exoplanet Archive, which is operated by the California Institute of Technology, under contract with the National Aeronautics and Space Administration under the Exoplanet Exploration Program. This work made use of the following Python packages: astropy (Astropy Collaboration 2013, 2018), lightkurve (Lightkurve Collaboration 2018), matplotlib (Hunter 2007), pandas (Wes McKinney 2010), seaborn (Waskom & The Seaborn Development team 2021), scipy (Virtanen et al. 2020) and numpy (Harris et al. 2020)., Context. Large sub-Neptunes are uncommon around the coolest stars in the Galaxy and are rarer still around those that are metal-poor. However, owing to the large planet-to-star radius ratio, these planets are highly suitable for atmospheric study via transmission spectroscopy in the infrared, such as with JWST. Aims. Here we report the discovery and validation of a sub-Neptune orbiting the thick-disk, mid-M dwarf star TOI-2406. The star's low metallicity and the relatively large size and short period of the planet make TOI-2406 b an unusual outcome of planet formation, and its characterisation provides an important observational constraint for formation models. Methods. We first infer properties of the host star by analysing the star's near-infrared spectrum, spectral energy distribution, and Gaia parallax. We use multi-band photometry to confirm that the transit event is on-target and achromatic, and we statistically validate the TESS signal as a transiting exoplanet. We then determine physical properties of the planet through global transit modelling of the TESS and ground-based time-series data. Results. We determine the host to be a metal-poor M4 V star, located at a distance of 56 pc, with properties T-eff = 3100 +/- 75 K, M-* = 0.162 +/- 0.008M(circle dot), R-* = 0.202 +/- 0.011R(circle dot), and [Fe/H] = -0.38 +/- 0.07, and a member of the thick disk. The planet is a relatively large sub-Neptune for the M-dwarf planet population, with R-p = 2.94 +/- 0.17R(circle plus) and P= 3.077 d, producing transits of 2% depth. We note the orbit has a non-zero eccentricity to 3 sigma, prompting questions about the dynamical history of the system. Conclusions. This system is an interesting outcome of planet formation and presents a benchmark for large-planet formation around metal-poor, low-mass stars. The system warrants further study, in particular radial velocity follow-up to determine the planet mass and constrain possible bound companions. Furthermore, TOI-2406 b is a good target for future atmospheric study through transmission spectroscopy. Although the planet's mass remains to be constrained, we estimate the S/N using amass-radius relationship, ranking the system fifth in the population of large sub-Neptunes, with TOI-2406 b having a much lower equilibrium temperature than other spectroscopically accessible members of this population., Heising-Simons Foundation, Programa de Apoyo a Proyectos de Investigacion e Innovacion Tecnologica (PAPIIT), Universidad Nacional Autonoma de Mexico IG-101321, Swiss National Science Foundation (SNSF), European Commission PP00P2-163967 PP00P2-190080 P2BEP2_195285, MIT's Kavli Institute as a Juan Carlos Torres Fellow, European Research Council (ERC) nffi 803193/BEBOP, MERAC foundation, UK Research & Innovation (UKRI), Science & Technology Facilities Council (STFC), Science and Technology Development Fund (STDF) nffi ST/S00193X/1, MIT's Kavli Institute as a Kavli postdoctoral fellow, Australian Research Council, Fonds de la Recherche Scientifique - FNRS FRFC 2.5.594.09.F, French Community of Belgium in the context of the FRIA Doctoral Grant, NASA High-End Computing (HEC) Program through the NASA Advanced Supercomputing (NAS) Division at Ames Research Center, NASA's Science Mission Directorate, National Aeronautics and Space Administration under the Exoplanet Exploration Program, TESS GI program G03274, National Science Foundation (NSF), Earths in Other Solar Systems Project (EOS), Alien Earths - NASA NNX15AD94G 80NSSC21K0593, High-Resolution Imaging instrument Zorro (Gemini program) GS-2020B-LP-105, NASA Exoplanet Exploration Program, National Aeronautics & Space Administration (NASA)
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35. TOI-1268b: The youngest hot Saturn-mass transiting exoplanet
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Subjak, J., Endl, M., Chaturvedi, P., Karjalainen, R., Cochran, W. D., Esposito, M., Gandolfi, D., Lam, K. W. F., Stassun, K.G., Žák, J., Lodieu, N., Boffin, H. M. J., MacQueen, P. J., Hatzes, A.P., Guenther, E. W., Georgieva, I., Grziwa, S., Schmerling, H., Skarka, M., Blazek, M., Karjalainen, M., Spokova, M., Isaacson, H., Howard, A. W., Burke, C. J., Van Eylen, V., Falk, B., Fridlund, M., Goffo, E., Jenkins, J. M., Korth, J., Lissauer, Jack J., Livingston, J., Luque, R., Muresan, A., Osborn, H. P., Palle, E., Persson, C. M., Redfield, S., Ricker, G.R., Seager, S., Serrano, L. M., Smith, A. M. S., Kabáth, P., Ministerio de Ciencia e Innovación (España), European Commission, and Fondazione Cassa di Risparmio di Torino
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Earth and Planetary Astrophysics (astro-ph.EP) ,techniques: spectroscopic / techniques: radial velocities / techniques: photometric / planetary systems / planets and satellites: gaseous planets / planets and satellites: atmospheres ,Planets and Satellites: Atmospheres ,Techniques: Photometric ,FOS: Physical sciences ,Techniques: Spectroscopic ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Space and Planetary Science ,Planets and Satellites: Gaseous Planets ,Astrophysics::Solar and Stellar Astrophysics ,Planetary Systems ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics::Galaxy Astrophysics ,Techniques: Radial Velocities ,Astrophysics - Earth and Planetary Astrophysics - Abstract
Full list of authors: Subjak, J.; Endl, M.; Chaturvedi, P.; Karjalainen, R.; Cochran, W. D.; Esposito, M.; Gandolfi, D.; Lam, K. W. F.; Stassun, K.; Zak, J.; Lodieu, N.; Boffin, H. M. J.; MacQueen, P. J.; Hatzes, A.; Guenther, E. W.; Georgieva, I.; Grziwa, S.; Schmerling, H.; Skarka, M.; Blazek, M.; Karjalainen, M.; Spokova, M.; Isaacson, H.; Howard, A. W.; Burke, C. J.; Van Eylen, V.; Falk, B.; Fridlund, M.; Goffo, E.; Jenkins, J. M.; Korth, J.; Lissauer, J. J.; Livingston, J. H.; Luque, R.; Muresan, A.; Osborn, H. P.; Palle, E.; Persson, C. M.; Redfield, S.; Ricker, G. R.; Seager, S.; Serrano, L. M.; Smith, A. M. S.; Kabath, P., We report the discovery of TOI-1268b, a transiting Saturn-mass planet from the TESS space mission. With an age of less than 1 Gyr, derived from various age indicators, TOI-1268b is the youngest Saturn-mass planet known to date; it contributes to the small sample of well-characterised young planets. It has an orbital period of P = 8.1577080 ± 0.0000044 days, and transits an early K-dwarf star with a mass of M* = 0.96 ± 0.04 M⊙, a radius of R* = 0.92 ± 0.06 R⊙, an effective temperature of Teff = 5300 ± 100 K, and a metallicity of 0.36 ± 0.06 dex. By combining TESS photometry with high-resolution spectra acquired with the Tull spectrograph at the McDonald Observatory, and the high-resolution spectrographs at the Tautenburg and Ondřejov Observatories, we measured a planetary mass of Mp = 96.4 ± 8.3 M⊕ and a radius of Rp = 9.1 ± 0.6 R⊕. TOI-1268 is an ideal system for studying the role of star-planet tidal interactions for non-inflated Saturn-mass planets. We used system parameters derived in this paper to constrain the planet’s tidal quality factor to the range of 104.5–5.3. When compared with the sample of other non-inflated Saturn-mass planets, TOI-1268b is one of the best candidates for transmission spectroscopy studies. © ESO 2022., This work was supported by the KESPRINT collaboration, an international consortium devoted to the characterisation and research of exoplanets discovered with space-based missions (www.kesprint.science). J.S., R.K., M.S., M.K. and P.K. would like to acknowledge support from MSMT grant LTT-20015. J.S. and P.K. acknowledge a travel budget from ERASMUS+ grant 2020-1-CZ01-KA203-078200. J.S. would like to acknowledge support from the Grant Agency of Charles University: GAUK No. 314421. P.C. acknowledges the generous support from Deutsche Forschungsgemeinschaft (DFG) of the grant CH 2636/1-1. We are grateful for the generous support by Thüringer Ministerium für Wirtschaft, Wissenschaft und Digitale Gesellschaft. K.W.F.L. was supported by Deutsche Forschungsgemeinschaft grants RA714/14-1 within the DFG Schwerpunkt SPP 1992, Exploring the Diversity of Extrasolar Planets. N.L. was financially supported by the Ministerio de Economia y Competitividad and the Fondo Europeo de Desarrollo Regional (FEDER) under AYA2015-69350-C3-2-P. E.G. is thankful for the generously supported by the by the Thüringer Ministerium für Wirtschaft, Wissenschaft und Digitale Gesellschaft and the staff of the Alfred-Jensch-Teleskop. I.G., M.F., J.K., and C.M.P., gratefully acknowledge the support of the Swedish National Space Agency (DNR 174/18, 2020-00104, 65/19). This work was supported by JSPS KAKENHI grant number 20K14518. R.L. acknowledges financial support from the Spanish Ministerio de Ciencia e Innovación, through project PID2019-109522GB-C52, and the Centre of Excellence “Severo Ochoa” award to the Instituto de Astrofísica de Andalucía (SEV-2017-0709). L.M.S. gratefully acknowledges financial support from the CRT foundation under Grant No. 2018.2323 “Gaseous or rocky? Unveiling the nature of small worlds”. This work has been carried out within the framework of the NCCR PlanetS supported by the Swiss National Science Foundation. We acknowledge the use of public TESS data from pipelines at the TESS Science Office and at the TESS Science Processing Operations Center. Resources supporting this work were provided by the NASA High-End Computing (HEC) Program through the NASA Advanced Supercomputing (NAS) Division at Ames Research Center for the production of the SPOC data products. This paper includes data collected with the TESS mission, obtained from the MAST data archive at the Space Telescope Science Institute (STScI). Funding for the TESS mission is provided by the NASA Explorer Program. STScI is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. This work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. This publication makes use of VOSA, developed under the Spanish Virtual Observatory project supported by the Spanish MINECO through grant AyA2017-84089. VOSA has been partially updated by using funding from the European Union’s Horizon 2020 Research and Innovation Programme, under Grant Agreement no 776403 (EXOPLANETS-A). This research has made use of the SIMBAD database, operated at CDS, Strasbourg, France.
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36. Multi-cavity gravito-acoustic oscillation modes in stars
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C. Pinçon and M. Takata
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Space and Planetary Science ,Astronomy and Astrophysics - Abstract
Context. Over recent decades, asteroseismology has proven to be a powerful method for probing stellar interiors. Analytical descriptions of the global oscillation modes, in combination with pulsation codes, have provided valuable help in processing and interpreting the large amount of seismic data collected, for instance, by space-borne missions CoRoT, Kepler, and TESS. These prior results have paved the way to more in-depth analyses of the oscillation spectra of stars in order to delve into subtle properties of their interiors. This purpose conversely requires innovative theoretical descriptions of stellar oscillations. Aims. In this paper, we aim to analytically express the resonance condition of the adiabatic oscillation modes of spherical stars in a very general way that is applicable at different evolutionary stages. Methods. In the present formulation, a star is represented as an acoustic interferometer composed of a multitude of resonant cavities where waves can propagate and the short-wavelength JWKB approximation is met. Each cavity is separated from the adjacent ones by barriers, which correspond to regions either where waves are evanescent or where the JWKB approximation fails. Each barrier is associated with a reflection and transmission coefficient. The stationary modes are then computed using two different physical representations: (1) studying the infinite-time reflections and transmissions of a wave energy ray through the ensemble of cavities or (2) solving the linear boundary value problem using the progressive matching of the wave function from one barrier to the adjacent one between the core and surface. Results. Both physical pictures provide the same resonance condition, which ultimately turns out to depend on a number of parameters: the reflection and transmission phase lags introduced by each barrier, the coupling factor associated with each barrier, and the wave number integral over each resonant cavity. Using such a formulation, we can retrieve, in a practical way, the usual forms derived in previous works in the case of mixed modes with two or three cavities coupled though evanescent barriers, low- and large-amplitude glitches, and the simultaneous presence of evanescent regions and glitches. Conclusions. The resonance condition obtained in this work provides a new tool that is useful in predicting the oscillation spectra of stars and interpreting seismic observations at different evolutionary stages in a simple way. Practical applications require more detailed analyses to make the link between the reflection-transmission parameters and the internal structure. These aspects will be the subject of a future paper.
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- 2022
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37. Accurate Einstein coefficients for electric dipole transitions in the first negative band of N2+
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Olfa Ferchichi, Najoua Derbel, Alexander Alijah, and Philippe Rousselot
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Space and Planetary Science ,Astronomy and Astrophysics - Abstract
Context. The N2+ fluorescence spectrum of comet C/2016 R2 is modelled in a companion paper. That work relies on accurate Einstein coefficients for electric dipole transitions between the B2∑u+ and X2∑g+ electronic states of N2+. Aims. These coefficients are provided in the present paper. Methods. The potential energy curves and transition dipole moments were computed at a high level of ab initio theory and include relativistic corrections. Rovibrational wavefunctions were then obtained without assuming separability of vibrational and rotational motions. Results. Vibrationally and rotationally resolved Einstein coefficients are presented in a convenient three-parameter functional form for three isotopologues. A possible explanation is given for the large variation in the experimental radiative lifetimes.
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- 2022
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38. Type II supernovae from the Carnegie Supernova Project-I
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Santiago González-Gaitán, L. Martinez, Gastón Folatelli, Joseph P. Anderson, M. Orellana, Peter Hoeflich, F. Forster, Nicholas B. Suntzeff, Melina C. Bersten, Carlos Contreras, Mario Hamuy, Mark M. Phillips, Christopher R. Burns, Eric Hsiao, P. J. Pessi, M. D. Stritzinger, T. de Jaeger, Claudia P. Gutiérrez, Nidia Morrell, Lluís Galbany, K. Ertini, National Science Foundation (US), Consejo Nacional de Investigaciones Científicas y Técnicas (Argentina), Villum Fonden, Independent Research Fund Denmark, and Ministerio de Ciencia, Innovación y Universidades (España)
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High Energy Astrophysical Phenomena (astro-ph.HE) ,Physics ,Infrared ,general [Supernovae] ,Supernovae: general ,FOS: Physical sciences ,Astronomy and Astrophysics ,Blanketing ,Astrophysics ,Light curve ,Luminosity ,Astronomía ,Photometry (optics) ,Supernova ,Wavelength ,Astrophysics - Solar and Stellar Astrophysics ,Space and Planetary Science ,Astrophysics - High Energy Astrophysical Phenomena ,Solar and Stellar Astrophysics (astro-ph.SR) ,Line (formation) - Abstract
The present study is the first of a series of three papers where we characterise the type II supernovae (SNe~II) from the Carnegie Supernova Project-I to understand their diversity in terms of progenitor and explosion properties. In this first paper, we present bolometric light curves of 74 SNe~II. We outline our methodology to calculate the bolometric luminosity, which consists of the integration of the observed fluxes in numerous photometric bands ($uBgVriYJH$) and black-body (BB) extrapolations to account for the unobserved flux at shorter and longer wavelengths. BB fits were performed using all available broadband data except when line blanketing effects appeared. Photometric bands bluer than $r$ that are affected by line blanketing were removed from the fit, which makes near-infrared (NIR) observations highly important to estimate reliable BB extrapolations to the infrared. BB fits without NIR data produce notably different bolometric light curves, and therefore different estimates of SN~II progenitor and explosion properties when data are modelled. We present two methods to address the absence of NIR observations: (a) colour-colour relationships from which NIR magnitudes can be estimated using optical colours, and (b) new prescriptions for bolometric corrections as a function of observed SN~II colours. Using our 74 SN~II bolometric light curves, we provide a full characterisation of their properties based on several observed parameters. We measured magnitudes at different epochs, as well as durations and decline rates of different phases of the evolution. An analysis of the light-curve parameter distributions was performed, finding a wide range and a continuous sequence of observed parameters which is consistent with previous analyses using optical light curves., Comment: Accepted for publication in A&A
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- 2022
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39. Event Horizon Telescope imaging of the archetypal blazar 3C 279 at an extreme 20 microarcsecond resolution
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Robert Freund, N. W. Halverson, Benjamin R. Ryan, Paul Shaw, André Young, Andreas Eckart, A. Montaña, Michael Titus, Chen Yu Yu, Gertie Geertsema, Gao Feng, Ronald Grosslein, Ranjani Srinivasan, David Ball, Pablo Torne, Roberto Garcia, Hiroki Okino, Kotaro Moriyama, Chris Eckert, Lupin C.C. Lin, Geoffrey B. Crew, Vernon Fath, Freek Roelofs, David Sánchez-Arguelles, Luciano Rezzolla, Makoto Inoue, Michael Bremer, Jongsoo Kim, James Hoge, Michael Janssen, David M. Gale, Mel Rose, Jason Dexter, Do-Young Byun, J. G. A. Wouterloot, Rubén Herrero-Illana, Daniel C. M. Palumbo, Ta Shun Wei, Ching Tang Liu, Bradford Benson, Jadyn Anczarski, Patrick M. Koch, Ken Young, Jae-Young Kim, Minfeng Gu, Mislav Baloković, Mariafelicia De Laurentis, Laurent Loinard, A. Jiménez-Rosales, Tomohisa Kawashima, Nicolas Pradel, Heino Falcke, Olivier Gentaz, Dirk Muders, Shami Chatterjee, Britton Jeter, Rocco Lico, Craig Walther, David J. James, Homin Jiang, Michael H. Hecht, Gopal Narayanan, Qingwen Wu, Pierre Martin-Cocher, Michael A. Nowak, Alexander W. Raymond, Gregory Desvignes, Anne Kathrin Baczko, Chet Ruszczyk, Yutaka Hasegawa, Chao-Te Li, M. C. H. Wright, Andrew Nadolski, Alan P. Marscher, Christopher Beaudoin, Harriet Parsons, Peñalver Juan, Karl M. Menten, Silke Britzen, Frédéric Gueth, Shu Hao Chang, Andrew Chael, Daryl Haggard, Rodrigo Córdova Rosado, Ru-Sen Lu, Mansour Karami, José L. Gómez, Sang-Sung Lee, Tirupati K. Sridharan, Karl Friedrich Schuster, Ronald Hesper, Richard L. Plambeck, Iain Coulson, Jason SooHoo, Aristeidis Noutsos, Svetlana G. Jorstad, Li Ming Lu, James M. Cordes, David H. Hughes, Jonathan Weintroub, Chih-Wei Locutus Huang, Katherine L. Bouman, Roger J. Cappallo, Lijing Shao, Christiaan D. Brinkerink, John Kuroda, Ramesh Karuppusamy, Iniyan Natarajan, Jessica Dempsey, George Nystrom, John E. Carlstrom, Sera Markoff, Mark Kettenis, Neal R. Erickson, Jason W. Henning, R. Laing, Huang Lei, Kevin A. Dudevoir, Ilje Cho, William Stahm, Juan-Carlos Algaba, Junhan Kim, Hotaka Shiokawa, Martin P. McColl, James M. Moran, Chi-kwan Chan, Timothy C. Chuter, Thomas W. Folkers, Yi Chen, Christopher Greer, Lia Medeiros, C. Y. Kuo, Kuo Chang Han, Shoko Koyama, William Snow, Rurik A. Primiani, Sjoerd T. Timmer, F. Peter Schloerb, Stephen R. McWhirter, Fumie Tazaki, Norbert Wex, Ming-Tang Chen, Nimesh A. Patel, Aaron Faber, Mark Derome, Kazunori Akiyama, W. B. Everett, Hiroshi Nagai, Andrei Lobanov, Ignacio Ruiz, Pierre Christian, N. Phillips, David C. Forbes, Don Sousa, Michael Lindqvist, Christopher Risacher, Wen Ping Lo, Geoffrey C. Bower, Bart Ripperda, Dominique Broguiere, Maciek Wielgus, Antony A. Stark, Raquel Fraga-Encinas, Hiroaki Nishioka, Philippe Raffin, Hugo Messias, Feryal Özel, Jun Yi Koay, Buell T. Jannuzi, Sandra Bustamente, Roberto Neri, Jinchi Hao, Ye-Fei Yuan, Garrett K. Keating, Lynn D. Matthews, Avery E. Broderick, Mark G. Rawlings, Ciriaco Goddi, Tod R. Lauer, Kamal Souccar, Alan L. Roy, S. Navarro, Luis C. Ho, Timothy Norton, Roger Brissenden, Doosoo Yoon, Jongho Park, Richard Lacasse, Paul T. P. Ho, Derek Ward-Thompson, Atish Kamble, Akihiko Hirota, S. Sánchez, D. A. Graham, Vincent Piétu, Kyle D. Massingill, M. Zeballos, Mahito Sasada, Hideo Ogawa, Ziri Younsi, Chih Cheng Chang, Alejandro F. Sáez-Madain, Christian M. Fromm, Ramesh Narayan, Shuichiro Tsuda, Ryan Berthold, Gibwa Musoke, Laura Vertatschitsch, Masanori Nakamura, Remo P. J. Tilanus, Cornelia Müller, Kimihiro Kimura, Roman Gold, Venkatessh Ramakrishnan, Yuzhu Cui, Frederick K. Baganoff, Alan R. Whitney, Aleksandar Popstefanija, Helge Rottmann, Yuan Feng, Ralph Eatough, Tuomas Savolainen, Neil M. Nagar, Alexander Allardi, M. Mora-Klein, Thomas Bronzwaer, Mark Gurwell, Bong Won Sohn, Ivan Marti-Vidal, Chih Chiang Han, Hung Yi Pu, Yan-Rong Li, Shan Shan Zhao, Song Chu Chang, Zhi-Qiang Shen, John F. C. Wardle, Carsten Kramer, Koushik Chatterjee, Wagner Jan, Tomoaki Oyama, Ray Blundell, Motoki Kino, Alan E. E. Rogers, Rebecca Azulay, Jordy Davelaar, Tyler Trent, Satoki Matsushita, Kazi L.J. Rygl, Shuo Zhang, John E. Barrett, Peter Oshiro, Ryan Chilson, Jorge A. Preciado-López, Daniel Michalik, Peter Galison, Uwe Bach, Ilse van Bemmel, Pim Schellart, Michael D. Johnson, Jiang Wu, J. Anton Zensus, S. A. Dzib, Arturo I. Gómez-Ruiz, Meyer Zhao Zheng, David John, Dimitrios Psaltis, Daniel P. Marrone, M. Poirier, Shiro Ikeda, Ralph G. Marson, A. Hernandez-Gomez, Sven Dornbusch, George Reiland, Mareki Honma, J. Blanchard, Ed Fomalont, Taehyun Jung, Izumi Mizuno, Monika Moscibrodzka, Vincent L. Fish, Matthew R. Dexter, Paul Tiede, Rodrigo Amestica, Nicholas R. MacDonald, Gisela N. Ortiz-León, Colin J. Lonsdale, Callie Matulonis, Charles F. Gammie, Per Friberg, Boris Georgiev, W. Boland, Ramprasad Rao, Guang-Yao Zhao, Joseph R. Farah, Zhiyuan Li, Hector Olivares, Sara Issaoun, Elisabetta Liuzzo, C. M. Violette Impellizzeri, Michael Kramer, Oliver Porth, Thomas P. Krichbaum, Dominic W. Pesce, Daniel R. van Rossum, David R. Smith, Robert Wharton, Kuan Yu Liu, David P. Woody, Arash Roshanineshat, Sheperd S. Doeleman, Chung Chen Chen, Ziyan Zhu, Ue-Li Pen, Yosuke Mizuno, Prather Ben, Sascha Trippe, Walter Alef, Liu Kuo, Alexandra S. Rahlin, William Montgomerie, George N. Wong, Jirong Mao, Kazuhiro Hada, Efthalia Traianou, John Conway, Remi Sassella, Eduardo Ros, Kevin M. Silva, Derek Kubo, E. Castillo-Domínguez, Huib Jan van Langevelde, Keiichi Asada, Des Small, Joseph Neilsen, Chi H. Nguyen, Chunchong Ni, Yusuke Kono, Ryan Keisler, Paul Yamaguchi, Lindy Blackburn, Erik M. Leitch, Roger Deane, Lucy M. Ziurys, K. T. Story, Joseph Crowley, Nathan Whitehorn, Stefan Heyminck, Kenji Toma, Antxon Alberdi, Yau De Huang, Dan Bintley, Y Kim, J., Krichbaum, T. P., Broderick, A. E., Wielgus, M., Blackburn, L., Gomez, J. -L., Johnson, M. D., Bouman, K. L., Chael, A., Akiyama, K., Jorstad, S., Marscher, A. P., Issaoun, S., Janssen, M., Chan, C. -K., Savolainen, T., Pesce, D. W., Ozel, F., De Laurentis, M., Deane, R., Institut de RadioAstronomie Millimétrique (IRAM), Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Instituto de RadioAstronomía Milimétrica (IRAM), Event Horizon Telescope, Ministerio de Economía y Competitividad (España), European Commission, National Aeronautics and Space Administration (US), Max Planck Institute for Radio Astronomy, Perimeter Institute for Theoretical Physics, Harvard University, CSIC, Princeton University, Boston University, Radboud University Nijmegen, University of Arizona, Anne Lähteenmäki Group, Academia Sinica - Institute of Astronomy and Astrophysics, Massachusetts Institute of Technology, East Asian Observatory, Nederlandse Onderzoekschool voor Astronomie, Academia Sinica, Institut de Radio Astronomie Millimétrique, Korea Astronomy and Space Science Institute, University of Chicago, Cornell University, University of Amsterdam, CAS - Shanghai Astronomical Observatory, Chalmers University of Technology, National Astronomical Observatory of Japan, University of Naples Federico II, University of Pretoria, University of Colorado Boulder, National Radio Astronomy Observatory, Goethe University Frankfurt, University of Illinois at Urbana-Champaign, University of Waterloo, Instituto Nacional de Astrofisica Optica y Electronica, University of Groningen, Peking University, Max Planck Institute for Extraterrestrial Physics, Joint Institute for VLBI in Europe, California Institute of Technology, National Sun Yat-sen University, National Optical Astronomy Observatory, CAS - Institute of High Energy Physics, Nanjing University, INAF Istituto di Radioastronomia, Instituto de Radioastronomía y Astrofísica, CAS - National Astronomical Observatories, Universidad de Valencia, Universidad de Concepción, University of Massachusetts, Rhodes University, University of California Berkeley, Los Alamos National Laboratory, IRAM, Tohoku University, Seoul National University, Brandeis University, University of Central Lancashire, Huazhong University of Science and Technology, University of Science and Technology of China, University of Vermont, Villanova University, United States Department of Energy, Western University, Royal Netherlands Meteorological Institute, McGill University, Osaka Prefecture University, European Southern Observatory Santiago, University of Manchester, National Radio Astronomy Observatory Socorro, Rochester Institute of Technology, Washington University St. Louis, Systems and Technology Research, Georgia Institute of Technology, Stanford University, University of California Los Angeles, Department of Electronics and Nanoengineering, Aalto-yliopisto, Aalto University, Astronomy, High Energy Astrophys. & Astropart. Phys (API, FNWI), and Gravitation and Astroparticle Physics Amsterdam
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ACTIVE GALACTIC NUCLEI ,Brightness ,Active galactic nucleus ,active [Galaxies] ,Astrophysics::High Energy Astrophysical Phenomena ,Astronomy ,galaxies: active ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Submillimeter Array ,FLOWS ,SCALE CIRCULAR-POLARIZATION ,0103 physical sciences ,Very-long-baseline interferometry ,Blazar ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Physics ,Event Horizon Telescope ,[PHYS]Physics [physics] ,Jet (fluid) ,010308 nuclear & particles physics ,Astronomy and Astrophysics ,FLARE ,galaxies: jets ,individual: 3C 279 [Galaxies] ,LONG ,VARIABILITY ,galaxies: individual: 3C 279 ,GAMMA-RAY ,QUASARS ,13. Climate action ,Space and Planetary Science ,techniques: interferometric ,Brightness temperature ,ACCRETION DISKS ,interferometric [Techniques] ,jets [Galaxies] ,RELATIVISTIC JETS ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] - Abstract
Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Open Access funding provided by Max Planck Society.--All authors: Kim, Jae-Young; Krichbaum, Thomas P.; Broderick, Avery E.; Wielgus, Maciek; Blackburn, Lindy; Gómez, José L.; Johnson, Michael D.; Bouman, Katherine L.; Chael, Andrew; Akiyama, Kazunori; Jorstad, Svetlana; Marscher, Alan P.; Issaoun, Sara; Janssen, Michael; Chan, Chi-kwan; Savolainen, Tuomas; Pesce, Dominic W.; Özel, Feryal; Alberdi, Antxon; Alef, Walter Asada, Keiichi; Azulay, Rebecca; Baczko, Anne-Kathrin; Ball, David; Baloković, Mislav; Barrett, John; Bintley, Dan; Boland, Wilfred; Bower, Geoffrey C.; Bremer, Michael; Brinkerink, Christiaan D.; Brissenden, Roger; Britzen, Silke; Broguiere, Dominique; Bronzwaer, Thomas; Byun, Do-Young; Carlstrom, John E.; Chatterjee, Shami; Chatterjee, Koushik; Chen, Ming-Tang; Chen, Yongjun; Cho, Ilje; Christian, Pierre; Conway, John E.; Cordes, James M.; Crew, Geoffrey B.; Cui, Yuzhu; Davelaar, Jordy; De Laurentis, Mariafelicia; Deane, Roger; Dempsey, Jessica; Desvignes, Gregory; Dexter, Jason; Doeleman, Sheperd S.; Eatough, Ralph P.; Falcke, Heino; Fish, Vincent L.; Fomalont, Ed; Fraga-Encinas, Raquel; Friberg, Per; Fromm, Christian M.; Galison, Peter; Gammie, Charles F.; García, Roberto; Gentaz, Olivier; Georgiev, Boris; Goddi, Ciriaco; Gold, Roman; Gómez-Ruiz, Arturo I.; Gu, Minfeng; Gurwell, Mark; Hada, Kazuhiro; Hecht, Michael H.; Hesper, Ronald; Ho, Luis C.; Ho, Paul; Honma, Mareki; Huang, Chih-Wei L.; Huang, Lei; Hughes, David H.; Ikeda, Shiro; Inoue, Makoto; James, David J.; Jannuzi, Buell T.; Jeter, Britton; Jiang, Wu; Jimenez-Rosales, Alejandra; Jung, Taehyun; Karami, Mansour; Karuppusamy, Ramesh; Kawashima, Tomohisa; Keating, Garrett K.; Kettenis, Mark; Kim, Junhan; Kim, Jongsoo; Kino, Motoki; Koay, Jun Yi; Koch, Patrick M.; Koyama, Shoko; Kramer, Michael; Kramer, Carsten; Kuo, Cheng-Yu; Lauer, Tod R.; Lee, Sang-Sung; Li, Yan-Rong; Li, Zhiyuan; Lindqvist, Michael; Lico, Rocco; Liu, Kuo; Liuzzo, Elisabetta; Lo, Wen-Ping; Lobanov, Andrei P.; Loinard, Laurent; Lonsdale, Colin; Lu, Ru-Sen; MacDonald, Nicholas R.; Mao, Jirong; Markoff, Sera; Marrone, Daniel P.; Martí-Vidal, Iván; Matsushita, Satoki; Matthews, Lynn D.; Medeiros, Lia; Menten, Karl M.; Mizuno, Yosuke; Mizuno, Izumi; Moran, James M.; Moriyama, Kotaro; Moscibrodzka, Monika; Musoke, Gibwa; Müller, Cornelia; Nagai, Hiroshi; Nagar, Neil M.; Nakamura, Masanori; Narayan, Ramesh; Narayanan, Gopal; Natarajan, Iniyan; Neri, Roberto; Ni, Chunchong; Noutsos, Aristeidis; Okino, Hiroki; Olivares, Héctor; Ortiz-León, Gisela N.; Oyama, Tomoaki; Palumbo, Daniel C. M.; Park, Jongho; Patel, Nimesh; Pen, Ue-Li; Piétu, Vincent; Plambeck, Richard; PopStefanija, Aleksandar; Porth, Oliver; Prather, Ben; Preciado-López, Jorge A.; Psaltis, Dimitrios; Pu, Hung-Yi; Ramakrishnan, Venkatessh; Rao, Ramprasad; Rawlings, Mark G.; Raymond, Alexander W.; Rezzolla, Luciano; Ripperda, Bart; Roelofs, Freek; Rogers, Alan; Ros, Eduardo; Rose, Mel; Roshanineshat, Arash; Rottmann, Helge; Roy, Alan L.; Ruszczyk, Chet; Ryan, Benjamin R.; Rygl, Kazi L. J.; Sánchez, Salvador; Sánchez-Arguelles, David; Sasada, Mahito; Schloerb, F. Peter; Schuster, Karl-Friedrich; Shao, Lijing; Shen, Zhiqiang; Small, Des; Sohn, Bong Won; SooHoo, Jason; Tazaki, Fumie; Tiede, Paul; Tilanus, Remo P. J.; Titus, Michael; Toma, Kenji; Torne, Pablo; Trent, Tyler; Traianou, Efthalia; Trippe, Sascha; Tsuda, Shuichiro; van Bemmel, Ilse; van Langevelde, Huib Jan; van Rossum, Daniel R.; Wagner, Jan; Wardle, John; Ward-Thompson, Derek; Weintroub, Jonathan; Wex, Norbert; Wharton, Robert; Wong, George N.; Wu, Qingwen; Yoon, Doosoo; Young, André; Young, Ken; Younsi, Ziri; Yuan, Feng; Yuan, Ye-Fei; Zensus, J. Anton; Zhao, Guangyao; Zhao, Shan-Shan; Zhu, Ziyan; Algaba, Juan-Carlos; Allardi, Alexander; Amestica, Rodrigo; Anczarski, Jadyn; Bach, Uwe; Baganoff, Frederick K.; Beaudoin, Christopher; Benson, Bradford A.; Berthold, Ryan; Blanchard, Jay M.; Blundell, Ray; Bustamente, Sandra; Cappallo, Roger; Castillo-Domínguez, Edgar; Chang, Chih-Cheng; Chang, Shu-Hao; Chang, Song-Chu; Chen, Chung-Chen; Chilson, Ryan; Chuter, Tim C.; Rosado, Rodrigo Córdova; Coulson, Iain M.; Crowley, Joseph; Derome, Mark; Dexter, Matthew; Dornbusch, Sven; Dudevoir, Kevin A.; Dzib, Sergio A.; Eckart, Andreas; Eckert, Chris; Erickson, Neal R.; Everett, Wendeline B.; Faber, Aaron; Farah, Joseph R.; Fath, Vernon; Folkers, Thomas W.; Forbes, David C.; Freund, Robert; Gale, David M.; Gao, Feng; Geertsema, Gertie; Graham, David A.; Greer, Christopher H.; Grosslein, Ronald; Gueth, Frédéric; Haggard, Daryl; Halverson, Nils W.; Han, Chih-Chiang; Han, Kuo-Chang; Hao, Jinchi; Hasegawa, Yutaka; Henning, Jason W.; Hernández-Gómez, Antonio; Herrero-Illana, Rubén; Heyminck, Stefan; Hirota, Akihiko; Hoge, James; Huang, Yau-De; Violette Impellizzeri, C. M.; Jiang, Homin; John, David; Kamble, Atish; Keisler, Ryan; Kimura, Kimihiro; Kono, Yusuke; Kubo, Derek; Kuroda, John; Lacasse, Richard; Laing, Robert A.; Leitch, Erik M.; Li, Chao-Te; Lin, Lupin C. -C.; Liu, Ching-Tang; Liu, Kuan-Yu; Lu, Li-Ming; Marson, Ralph G.; Martin-Cocher, Pierre L.; Massingill, Kyle D.; Matulonis, Callie; McColl, Martin P.; McWhirter, Stephen R.; Messias, Hugo; Meyer-Zhao, Zheng; Michalik, Daniel; Montaña, Alfredo; Montgomerie, William; Mora-Klein, Matias; Muders, Dirk; Nadolski, Andrew; Navarro, Santiago; Neilsen, Joseph; Nguyen, Chi H.; Nishioka, Hiroaki; Norton, Timothy; Nowak, Michael A.; Nystrom, George; Ogawa, Hideo; Oshiro, Peter; Oyama, Tomoaki; Parsons, Harriet; Peñalver, Juan; Phillips, Neil M.; Poirier, Michael; Pradel, Nicolas; Primiani, Rurik A.; Raffin, Philippe A.; Rahlin, Alexandra S.; Reiland, George; Risacher, Christopher; Ruiz, Ignacio; Sáez-Madaín, Alejandro F.; Sassella, Remi; Schellart, Pim; Shaw, Paul; Silva, Kevin M.; Shiokawa, Hotaka; Smith, David R.; Snow, William; Souccar, Kamal; Sousa, Don; Sridharan, Tirupati K.; Srinivasan, Ranjani; Stahm, William; Stark, Antony A.; Story, Kyle; Timmer, Sjoerd T.; Vertatschitsch, Laura; Walther, Craig; Wei, Ta-Shun; Whitehorn, Nathan; Whitney, Alan R.; Woody, David P.; Wouterloot, Jan G. A.; Wright, Melvin; Yamaguchi, Paul; Yu, Chen-Yu; Zeballos, Milagros; Zhang, Shuo; Ziurys, Lucy; Event Horizon Telescope Collaboration, 3C 279 is an archetypal blazar with a prominent radio jet that show broadband flux density variability across the entire electromagnetic spectrum. We use an ultra-high angular resolution technique - global Very Long Baseline Interferometry (VLBI) at 1.3mm (230 GHz) - to resolve the innermost jet of 3C 279 in order to study its fine-scale morphology close to the jet base where highly variable-ray emission is thought to originate, according to various models. The source was observed during four days in April 2017 with the Event Horizon Telescope at 230 GHz, including the phased Atacama Large Millimeter/submillimeter Array, at an angular resolution of ∼20 μas (at a redshift of z = 0:536 this corresponds to ∼0:13 pc ∼ 1700 Schwarzschild radii with a black hole mass MBH = 8 × 108 M⊙). Imaging and model-fitting techniques were applied to the data to parameterize the fine-scale source structure and its variation.We find a multicomponent inner jet morphology with the northernmost component elongated perpendicular to the direction of the jet, as imaged at longer wavelengths. The elongated nuclear structure is consistent on all four observing days and across diffierent imaging methods and model-fitting techniques, and therefore appears robust. Owing to its compactness and brightness, we associate the northern nuclear structure as the VLBI "core". This morphology can be interpreted as either a broad resolved jet base or a spatially bent jet.We also find significant day-to-day variations in the closure phases, which appear most pronounced on the triangles with the longest baselines. Our analysis shows that this variation is related to a systematic change of the source structure. Two inner jet components move non-radially at apparent speeds of ∼15 c and ∼20 c (∼1:3 and ∼1:7 μas day-1, respectively), which more strongly supports the scenario of traveling shocks or instabilities in a bent, possibly rotating jet. The observed apparent speeds are also coincident with the 3C 279 large-scale jet kinematics observed at longer (cm) wavelengths, suggesting no significant jet acceleration between the 1.3mm core and the outer jet. The intrinsic brightness temperature of the jet components are ≤1010 K, a magnitude or more lower than typical values seen at ≥7mm wavelengths. The low brightness temperature and morphological complexity suggest that the core region of 3C 279 becomes optically thin at short (mm) wavelengths. © J.-Y. Kim et al. 2020., The authors of the present paper thank the following organizations and programs: the Academy of Finland (projects 274477, 284495, 312496); the Advanced European Network of E-infrastructures for Astronomy with the SKA (AENEAS) project, supported by the European Commission Framework Programme Horizon 2020 Research and Innovation action under grant agreement 731016; the Alexander von Humboldt Stiftung; the Black Hole Initiative at Harvard University, through a grant (60477) from the John Templeton Foundation; the China Scholarship Council; Comision Nacional de Investigacion Cientifica y Tecnologica (CONICYT, Chile, via PIA ACT172033, Fondecyt projects 1171506 and 3190878, BASAL AFB-170002, ALMA-conicyt 31140007); Consejo Nacional de Ciencia y Tecnologia (CONACYT, Mexico, projects 104497, 275201, 279006, 281692); the Delaney Family via the Delaney Family John A. Wheeler Chair at Perimeter Institute; Direccion General de Asuntos del Personal Academico -Universidad Nacional Autonoma de Mexico (DGAPA -UNAM, project IN112417); the European Research Council Synergy Grant "BlackHoleCam: Imaging the Event Horizon of Black Holes" (grant 610058); the Generalitat Valenciana postdoctoral grant APOSTD/2018/177 and GenT Program (project CIDEGENT/2018/021); the Gordon and Betty Moore Foundation (grants GBMF-3561, GBMF-5278); the Istituto Nazionale di Fisica Nucleare (INFN) sezione di Napoli, iniziative specifiche TEONGRAV; the International Max Planck Research School for Astronomy and Astrophysics at the Universities of Bonn and Cologne; the Jansky Fellowship program of the National Radio Astronomy Observatory (NRAO); the Japanese Government (Monbukagakusho: MEXT) Scholarship; the Japan Society for the Promotion of Science (JSPS) Grant-inAid for JSPS Research Fellowship (JP17J08829); the Key Research Program of Frontier Sciences, Chinese Academy of Sciences (CAS, grants QYZDJSSW-SLH057, QYZDJ-SSW-SYS008, ZDBS-LY-SLH011); the Leverhulme Trust Early Career Research Fellowship; the Malaysian Fundamental Research Grant Scheme (FRGS, grant FRGS/1/2019/STG02/UM/02/6); the Max-PlanckGesellschaft (MPG); the Max Planck Partner Group of the MPG and the CAS; the MEXT/JSPS KAKENHI (grants 18KK0090, JP18K13594, JP18K03656, JP18H03721, 18K03709, 18H01245, 25120007); the MIT International Science and Technology Initiatives (MISTI) Funds; the Ministry of Science and Technology (MOST) of Taiwan (105-2112-M-001-025-MY3, 106-2112-M-001-011, 106-2119-M-001-027, 107-2119-M-001-017, 107-2119-M-001-020, and 107-2119-M-110-005); the National Aeronautics and Space Administration (NASA, Fermi Guest Investigator grant 80NSSC17K0649 and Hubble Fellowship grant HST-HF2-51431.001-A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc. r , for NASA, under contract NAS5-26555); the National Institute of Natural Sciences (NINS) of Japan; the National Key Research and Development Program of China (grant 2016YFA0400704, 2016YFA0400702); the National Science Foundation (NSF, grants AST-0096454, AST-0352953, AST-0521233, AST-0705062, AST-0905844, AST-0922984, AST-1126433, AST-1140030, DGE-1144085, AST-1207704, AST-1207730, AST-1207752, MRI-1228509, OPP-1248097, AST-1310896, AST-1312651, AST-1337663, AST-1440254, AST-1555365, AST-1715061, AST-1615796, AST-1716327, OISE-1743747, AST-1816420); the Natural Science Foundation of China (grants 11573051, 11633006, 11650110427, 10625314, 11721303, 11725312, 11933007); the Natural Sciences and Engineering Research Council of Canada (NSERC, including a Discovery Grant and the NSERC Alexander Graham Bell Canada Graduate Scholarships-Doctoral Program); the National Youth Thousand Talents Program of China; the National Research Foundation of Korea (the Global PhD Fellowship Grant: grants NRF-2015H1A2A1033752, 2015-R1D1A1A01056807, the Korea Research Fellowship Program: NRF-2015H1D3A1066561); the Netherlands Organization for Scientific Research (NWO) VICI award (grant 639.043.513) and Spinoza Prize SPI 78-409; the New Scientific Frontiers with Precision Radio Interferometry Fellowship awarded by the South African Radio Astronomy Observatory (SARAO), which is a facility of the National Research Foundation (NRF), an agency of the Department of Science and Technology (DST) of South Africa; the Onsala Space Observatory (OSO) national infrastructure, for the provisioning of its facilities/observational support (OSO receives funding through the Swedish Research Council under grant 2017-00648) the Perimeter Institute for Theoretical Physics (research at Perimeter Institute is supported by the Government of Canada through the Department of Innovation, Science and Economic Development and by the Province of Ontario through the Ministry of Research, Innovation and Science); the Russian Science Foundation (grant 17-12-01029); the Spanish Ministerio de Economia y Competitividad (grants PGC2018-098915-B-C21, AYA201680889-P); the State Agency for Research of the Spanish MCIU through the "Center of Excellence Severo Ochoa" award for the Instituto de Astrofisica de Andalucia (SEV-2017-0709); the Toray Science Foundation; the US Department of Energy (USDOE) through the Los Alamos National Laboratory (operated by Triad National Security, LLC, for the National Nuclear Security Administration of the USDOE (Contract 89233218CNA000001)); the Italian Ministero dell'Istruzione Universita e Ricerca through the grant Progetti Premiali 2012-iALMA (CUP C52I13000140001); the European Union's Horizon 2020 research and innovation programme under grant agreement No 730562 RadioNet; ALMA North America Development Fund; the Academia Sinica; Chandra TM6-17006X; the GenT Program (Generalitat Valenciana) Project CIDEGENT/2018/021. This work used the Extreme Science and Engineering Discovery Environment (XSEDE), supported by NSF grant ACI-1548562, and CyVerse, supported by NSF grants DBI-0735191, DBI-1265383, and DBI1743442. XSEDE Stampede2 resource at TACC was allocated through TGAST170024 and TG-AST080026N. XSEDE JetStream resource at PTI and TACC was allocated through AST170028. The simulations were performed in part on the SuperMUC cluster at the LRZ in Garching, on the LOEWE cluster in CSC in Frankfurt, and on the HazelHen cluster at the HLRS in Stuttgart. This research was enabled in part by support provided by Compute Ontario (http://computeontario. r ca), Calcul Quebec (http://www.calculquebec.ca) and Compute Canada (http://www.computecanada.ca).We thank the sta ff at the participating observatories, correlation centers, and institutions for their enthusiastic support. This paper makes use of the following ALMA data: ADS/JAO.ALMA#2016.1.01154.V, ADS/JAO.ALMA#2016.1.01176.V. ALMA is a partnership of the European Southern Observatory (ESO; Europe, representing its member states), NSF, and National Institutes of Natural Sciences of Japan, together with National Research Council (Canada), Ministry of Science and Technology (MOST; Taiwan), Academia Sinica Institute of Astronomy and Astrophysics (ASIAA; Taiwan), and Korea Astronomy and Space Science Institute (KASI; Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, Associated Universities, Inc. (AUI)/NRAO, and the National Astronomical Observatory of Japan (NAOJ). The NRAO is a facility of the NSF operated under cooperative agreement by AUI. APEX is a collaboration between the Max-Planck-Institut fur Radioastronomie (Germany), ESO, and the Onsala Space Observatory (Sweden). The SMA is a joint project between the SAO and ASIAA and is funded by the Smithsonian Institution and the Academia Sinica. The JCMT is operated by the East Asian Observatory on behalf of the NAOJ, ASIAA, and KASI, as well as the Ministry of Finance of China, Chinese Academy of Sciences, and the National Key R&D Program (No. 2017YFA0402700) of China. Additional funding support for the JCMT is provided by the Science and Technologies Facility Council (UK) and participating universities in the UK and Canada. The LMT is a project operated by the Instituto Nacional de Astrofisica, Optica, y Electronica (Mexico) and the University of Massachusetts at Amherst (USA). The IRAM 30-m telescope on Pico Veleta, Spain is operated by IRAM and supported by CNRS (Centre National de la Recherche Scientifique, France), MPG (Max-Planck-Gesellschaft, Germany) and IGN (Instituto Geografico Nacional, Spain). The SMT is operated by the Arizona Radio Observatory, a part of the Steward Observatory of the University of Arizona, with financial support of operations from the State of Arizona and financial support for instrumentation development from the NSF. The SPT is supported by the National Science Foundation through grant PLR1248097. Partial support is also provided by the NSF Physics Frontier Center grant PHY-1125897 to the Kavli Institute of Cosmological Physics at the University of Chicago, the Kavli Foundation and the Gordon and Betty Moore Foundation grant GBMF 947. The SPT hydrogen maser was provided on loan from the GLT, courtesy of ASIAA. The EHTC has received generous donations of FPGA chips from Xilinx Inc., under the Xilinx University Program. The EHTC has benefited from technology shared under open-source license by the Collaboration for Astronomy Signal Processing and Electronics Research (CASPER). The EHT project is grateful to T4Science and Microsemi for their assistance with Hydrogen Masers. This research has made use of NASA's Astrophysics Data System. We gratefully acknowledge the support provided by the extended sta ff of the ALMA, both from the inception of the ALMA Phasing Project through the observational campaigns of 2017 and 2018. We would like to thank A. Deller and W. Brisken for EHT-specific support with the use of DiFX. We acknowledge the significance that Maunakea, where the SMA and JCMT EHT stations are located, has for the indigenous Hawaiian people. r This research has made use of data obtained with the Global Millimeter VLBI Array (GMVA), which consists of telescopes operated by the MPIfR, IRAM, Onsala, Metsahovi, Yebes, the Korean VLBI Network, the Green Bank Observatory and the Very Long Baseline Array (VLBA). The VLBA is an instrument of the National Radio Astronomy Observatory. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated by Associated Universities, Inc. The data were correlated at the correlator of the MPIfR in Bonn, Germany. This study makes use of 43 GHz VLBA data from the VLBA-BU Blazar Monitoring Program (VLBABU-BLAZAR; http://www.bu.edu/blazars/VLBAproject.html), funded by NASA through the Fermi Guest Investigator Program.
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- 2020
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40. The origin of the high metallicity of close-in giant exoplanets
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S. Shibata, R. Helled, and M. Ikoma
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Earth and Planetary Astrophysics (astro-ph.EP) ,Space and Planetary Science ,Physics::Space Physics ,Astrophysics::Solar and Stellar Astrophysics ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics::Galaxy Astrophysics ,Astrophysics - Earth and Planetary Astrophysics - Abstract
The composition of giant planets reflects their formation history. Planetesimal accretion during the phase of planetary migration could lead to the delivery of heavy elements into giant planets. In our previous paper (Shibata et al. 2020) we showed that planetesimal accretion during planetary migration occurs in a rather narrow region of the protoplanetary disk, which we refer as "the sweet spot for accretion". The goal of this paper is to reveal the nature of the sweet spot and investigate the role of the sweet spot in determining the composition of gas giant planets. We analytically derive the required conditions for the sweet spot. Then, we compare the derived equations with the numerical simulations. We find that the conditions required for the sweet spot can be expressed by the ratio of the gas damping timescale of the planetesimal orbits and the planetary migration timescale. If the planetary migration timescale depends on the surface density of disk gas inversely, the location of the sweet spot does not change with the disk evolution. The mass of planetesimals accreted by the planet depends on the amount of planetesimals that are shepherded by mean motion resonances. Our analysis suggests that tens Earth-mass of planetesimals can be shepherded into the sweet spot without planetesimal collisions. However, as more planetesimals are trapped into mean motion resonances, collisional cascade can lead to fragmentation of planetesimals. This could affect the location of the sweet spot and the population of small objects in planetary systems. We conclude that the composition of gas giant planets depends on whether the planets crossed the sweet spot during their formation. Constraining the metallicity of cold giant planets, that are expected to be outer than the sweet spot, would reveal key information for understanding the origin of heavy elements in giant planets., Comment: 17 pages, 13 figures, A&A accepted
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- 2022
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41. Unravelling the origin of extended radio emission in narrow-line Seyfert 1 galaxies with the JVLA
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Marco Berton, Enrico Congiu, Rohan Dahale, Robert Antonucci, L. Crepaldi, and Emilia Järvelä
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Physics ,Spectral index ,Active galactic nucleus ,Star formation ,Astrophysics::High Energy Astrophysical Phenomena ,Spatially resolved ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Astrophysical jet ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,Astrophysics::Galaxy Astrophysics ,Line (formation) - Abstract
Narrow-line Seyfert 1 (NLS1) galaxies are believed to be active galactic nuclei (AGN) in the early stages of their evolution. Some dozens of them have been found to host relativistic jets, whilst the majority has not even been detected in radio, emphasising the heterogeneity of the class in this band. In this paper, our aim is to determine the predominant source of radio emission in a sample of 44 NLS1s, selected based on their extended kpc-scale radio morphologies at 5.2 GHz. We accomplish this by analysing their spatially resolved radio spectral index maps, centred at 5.2 GHz. In addition, we utilise several diagnostics based on mid-infrared emission to estimate the star formation activity of their host galaxies. These data are complemented by archival data to draw a more complete picture of each source. We find an extraordinary diversity among our sample. Approximately equal fractions of our sources can be identified as AGN-dominated, composite, and host-dominated. Among the AGN-dominated sources are a few NLS1s with very extended jets, reaching distances of tens of kpc from the nucleus. One of these, J0814+5609, hosts the most extended jets found in an NLS1 so far. We also identify five NLS1s that could be classified as compact steep-spectrum sources. We further conclude that due to the variety seen in NLS1s simple proxies, such as the star formation diagnostics also employed in this paper, and the radio loudness parameter, are not ideal tools for characterising NLS1s. We emphasise the necessity of examining NLS1s as individuals, instead of making assumptions based on their classification. When these issues are properly taken into account, NLS1s offer an exceptional environment to study the interplay of the host galaxy and several AGN-related phenomena, such as jets and outflows. [Abstract abridged.], 83 pages, 51 figures, accepted for publication in Astronomy & Astrophysics
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- 2022
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42. Coupling between turbulence and solar-like oscillations: A combined Lagrangian PDF/SPH approach
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Kevin Belkacem, M.-J. Goupil, J. Philidet, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)
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FOS: Physical sciences ,Probability density function ,Astrophysics ,01 natural sciences ,methods: analytical ,010305 fluids & plasmas ,Physics::Fluid Dynamics ,Smoothed-particle hydrodynamics ,Stochastic differential equation ,symbols.namesake ,0103 physical sciences ,010303 astronomy & astrophysics ,Solar and Stellar Astrophysics (astro-ph.SR) ,Physics ,Turbulence ,turbulence ,Mathematical analysis ,Fluid Dynamics (physics.flu-dyn) ,Time evolution ,stars: solar-type ,Astronomy and Astrophysics ,Eulerian path ,Physics - Fluid Dynamics ,Acoustic wave ,Wave equation ,Astrophysics - Solar and Stellar Astrophysics ,Space and Planetary Science ,symbols ,stars: oscillations ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] - Abstract
Aims. This series of papers aims at building a new formalism specifically tailored to study the impact of turbulence on the global modes of oscillation in solar-like stars. This first paper aims at deriving a linear wave equation that directly and consistently contains the turbulence as an input to the model, and therefore naturally contains the information on the coupling between the turbulence and the modes, through the stochasticity of the equations. Methods. We use a Lagrangian stochastic model of turbulence based on Probability Density Function methods to describe the evolution of the properties of individual fluid particles through stochastic differential equations. We then transcribe these stochastic differential equations from a Lagrangian frame to an Eulerian frame, more adapted to the analysis of stellar oscillations. We combine this method with Smoothed Particle Hydrodynamics, where all the mean fields appearing in the Lagrangian stochastic model are estimated directly from the set of fluid particles themselves, through the use of a weighting kernel function allowing to filter the particles present in any given vicinity. The resulting stochastic differential equations on Eulerian variables are then linearised. Results. We obtain a stochastic, linear wave equation governing the time evolution of the relevant wave variables, while at the same time containing the effect of turbulence. The wave equation generalises the classical, unperturbed propagation of acoustic waves in a stratified medium to a form that, by construction, accounts for the impact of turbulence on the mode in a consistent way. The effect of turbulence consists in a non-homogeneous forcing term, responsible for the stochastic driving of the mode, and a stochastic perturbation to the homogeneous part of the wave equation, responsible for both the damping of the mode and the modal surface effects., Paper accepted for publication in A&A. 18 pages (12 without Appendices), 1 figure. Typos corrected
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- 2021
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43. Energetic ions in the Venusian system: Insights from the first Solar Orbiter flyby
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R. C. Allen, I. Cernuda, D. Pacheco, L. Berger, Z. G. Xu, J. L. Freiherr von Forstner, J. Rodríguez-Pacheco, R. F. Wimmer-Schweingruber, G. C. Ho, G. M. Mason, S. K. Vines, Y. Khotyaintsev, T. Horbury, M. Maksimovic, L. Z. Hadid, M. Volwerk, A. P. Dimmock, L. Sorriso-Valvo, K. Stergiopoulou, G. B. Andrews, V. Angelini, S. D. Bale, S. Boden, S. I. Böttcher, T. Chust, S. Eldrum, P. P. Espada, F. Espinosa Lara, V. Evans, R. Gómez-Herrero, J. R. Hayes, A. M. Hellín, A. Kollhoff, V. Krasnoselskikh, M. Kretzschmar, P. Kühl, S. R. Kulkarni, W. J. Lees, E. Lorfèvre, C. Martin, H. O’Brien, D. Plettemeier, O. R. Polo, M. Prieto, A. Ravanbakhsh, S. Sánchez-Prieto, C. E. Schlemm, H. Seifert, J. Souček, M. Steller, Š. Štverák, J. C. Terasa, P. Trávníček, K. Tyagi, A. Vaivads, A. Vecchio, and M. Yedla
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Physics ,planets and satellites ,Astronomy ,turbulence ,Astronomy and Astrophysics ,Astrophysics ,Fusion, Plasma and Space Physics ,Astrobiology ,Ion ,law.invention ,planets and satellites: terrestrial planets ,Fusion, plasma och rymdfysik ,Orbiter ,Astronomi, astrofysik och kosmologi ,Space and Planetary Science ,law ,Physics::Space Physics ,planet-star interactions ,terrestrial planets ,Astronomy, Astrophysics and Cosmology ,waves ,Astrophysics::Earth and Planetary Astrophysics ,planetary systems ,acceleration of particles - Abstract
The Solar Orbiter flyby of Venus on 27 December 2020 allowed for an opportunity to measure the suprathermal to energetic ions in the Venusian system over a large range of radial distances to better understand the acceleration processes within the system and provide a characterization of galactic cosmic rays near the planet. Bursty suprathermal ion enhancements (up to ∼10 keV) were observed as far as ∼50RVdowntail. These enhancements are likely related to a combination of acceleration mechanisms in regions of strong turbulence, current sheet crossings, and boundary layer crossings, with a possible instance of ion heating due to ion cyclotron waves within the Venusian tail. Upstream of the planet, suprathermal ions are observed that might be related to pick-up acceleration of photoionized exospheric populations as far as 5RVupstream in the solar wind as has been observed before by missions such as Pioneer Venus Orbiter and Venus Express. Near the closest approach of Solar Orbiter, the Galactic cosmic ray (GCR) count rate was observed to decrease by approximately 5 percent, which is consistent with the amount of sky obscured by the planet, suggesting a negligible abundance of GCR albedo particles at over 2RV. Along with modulation of the GCR population very close to Venus, the Solar Orbiter observations show that the Venusian system, even far from the planet, can be an effective accelerator of ions up to ∼30 keV. This paper is part of a series of the first papers from the Solar Orbiter Venus flyby.
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- 2021
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44. The Galaxy Activity, Torus, and Outflow Survey (GATOS)
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Leonard Burtscher, Santiago García-Burillo, A. Alonso-Herrero, Andrew Bunker, David J. Rosario, P. G. Boorman, Chris Packham, Dimitra Rigopoulou, Miguel Pereira-Santaella, Begoña García-Lorenzo, L. K. Hunt, Francoise Combes, C. Ramos Almeida, Patrick F. Roche, Kohei Ichikawa, Takuma Izumi, Alvaro Labiano, T. Taro Shimizu, N. A. Levenson, Tanio Díaz-Santos, Claudio Ricci, David Williamson, Omaira González-Martín, Masatoshi Imanishi, Marko Stalevski, E. Lopez-Rodriguez, Poshak Gandhi, I. García-Bernete, E. K. S. Hicks, D. Rouan, Koji Wada, Sebastian F. Hönig, and Ric Davies
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INFRARED-SPECTRA ,GALACTIC NUCLEI ,Galaxies: Seyfert ,Active galactic nucleus ,Astrophysics::High Energy Astrophysical Phenomena ,Continuum (design consultancy) ,FOS: Physical sciences ,galaxies [submillimeter] ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,galaxies [infrared] ,01 natural sciences ,Submillimeter Array ,STAR-FORMATION ,Seyfert [galaxies] ,RADIATION-PRESSURE ,0103 physical sciences ,Radiative transfer ,Astrophysics::Solar and Stellar Astrophysics ,SPACE-TELESCOPE ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Line (formation) ,Physics ,Luminous infrared galaxy ,ISM [galaxies] ,OBSCURING TORI ,MOLECULAR TORI ,010308 nuclear & particles physics ,Submillimeter: Galaxies ,Astronomy and Astrophysics ,Torus ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Infrared: Galaxies ,Galaxies: ISM ,NARROW-LINE REGION ,Physics and Astronomy ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,Astrophysics::Earth and Planetary Astrophysics ,SUBARCSECOND MIDINFRARED VIEW ,CLUMPY TORUS - Abstract
We compare mid-IR and ALMA far-IR images of 12 nearby Seyferts selected from GATOS. The mid-IR unresolved emission contributes more than 60% of the nuclear emission in most galaxies. By contrast, the ALMA 870micron continuum emission is mostly resolved and typically along the torus equatorial direction (Paper I, Garcia-Burillo et al. 2021). The Eddington ratios and nuclear hydrogen column densities NH of half the sample are favorable to launching polar and/or equatorial dusty winds, according to simulations. Six show mid-IR extended emission in the polar direction as traced by the NLR and perpendicular to the ALMA emission. In a few, the nuclear NH might be too high to uplift large quantities of dusty material along the polar direction. Five galaxies have low NH and/or Eddington ratios and thus polar dusty winds are not likely. We generate new CAT3D-WIND disk-wind model images. At low wind-to-disk cloud ratios the far-IR model images have disk- and ring-like morphologies. The X-shape associated with dusty winds is seen better in the far-IR at intermediate-high inclinations for the extended-wind configurations. In most models, the mid-IR emission comes from the inner part of the disk/cone. Extended bi-conical and one-sided polar mid-IR emission is seen in extended-wind configurations and high wind-to-disk cloud ratios. When convolved to our resolution, the model images reproduce qualitative aspects of the observed morphologies. Low-intermediate wind-to-disk ratios are required to account for the large fractions of unresolved mid-IR emission. This work and Paper I provide observational support for the torus+wind scenario. The wind component is more relevant at high Eddington ratios and/or AGN luminosities, and polar dust emission is predicted at NH of up to $10^{24}$cm$^{-2}$. The torus/disk component, on the other hand, prevails at low luminosities and/or Eddington ratios. (Abridged), 27 pages, 27 figures. Accepted for publication in A&A
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- 2021
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45. CAPOS: The bulge Cluster APOgee Survey
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Verne V. Smith, Antonela Monachesi, D. A. García-Hernández, Jennifer Sobeck, Rebecca Lane, S. Meszaros, Roger E. Cohen, J. G. Fernandez-Trincado, Nicolas F. Martin, Felipe Gran, Baitian Tang, Henrik Jönsson, Ricardo R. Muñoz, Beatriz Barbuy, Else Starkenburg, Doug Geisler, Lorenzo Monaco, F. Mauro, Márcio Catelan, D. González-Díaz, Joel R. Brownstein, K. M. Cunha, J. E. O'Connell, Sandro Villanova, A. Rojas-Arriagada, C. E. Ferreira Lopes, C. Muñoz, Lady Henao, Y. Reinarz, Dante Minniti, R. Contreras Ramos, Cristián E. Cortés, Javier Alonso-García, Danny Horta, C. Moni Bidin, S. R. Majewski, Manuela Zoccali, T. A. Santander, Timothy C. Beers, Celeste Parisi, A. Arentsen, R. E. Miranda, and Astronomy
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Physics ,stars: abundances ,010308 nuclear & particles physics ,Metallicity ,FOS: Physical sciences ,Astronomy and Astrophysics ,Context (language use) ,Astrophysics ,globular clusters: general ,Astrophysics - Astrophysics of Galaxies ,01 natural sciences ,Galaxy: bulge ,Radial velocity ,Stars ,Space and Planetary Science ,Bulge ,Astrophysics of Galaxies (astro-ph.GA) ,Globular cluster ,0103 physical sciences ,Cluster (physics) ,010303 astronomy & astrophysics - Abstract
Context. Bulge globular clusters (BGCs) are exceptional tracers of the formation and chemodynamical evolution of this oldest Galactic component. However, until now, observational difficulties have prevented us from taking full advantage of these powerful Galactic archeological tools. Aims. CAPOS, the bulge Cluster APOgee Survey, addresses this key topic by observing a large number of BGCs, most of which have only been poorly studied previously. Even their most basic parameters, such as metallicity, [{\alpha}/Fe], and radial velocity, are generally very uncertain. We aim to obtain accurate mean values for these parameters, as well as abundances for a number of other elements, and explore multiple populations. In this first paper, we describe the CAPOS project and present initial results for seven BGCs. Methods. CAPOS uses the APOGEE-2S spectrograph observing in the H band to penetrate obscuring dust toward the bulge. For this initial paper, we use abundances derived from ASPCAP, the APOGEE pipeline. Results. We derive mean [Fe/H] values of $-$0.85$\pm$0.04 (Terzan 2), $-$1.40$\pm$0.05 (Terzan 4), $-$1.20$\pm$0.10 (HP 1), $-$1.40$\pm$0.07 (Terzan 9), $-$1.07$\pm$0.09 (Djorg 2), $-$1.06$\pm$0.06 (NGC 6540), and $-$1.11$\pm$0.04 (NGC 6642) from three to ten stars per cluster. We determine mean abundances for eleven other elements plus the mean [$\alpha$/Fe] and radial velocity. CAPOS clusters significantly increase the sample of well-studied Main Bulge globular clusters (GCs) and also extend them to lower metallicity. We reinforce the finding that Main Bulge and Main Disk GCs, formed in situ, have [Si/Fe] abundances slightly higher than their accreted counterparts at the same metallicity. We investigate multiple populations and find our clusters generally follow the light-element (anti)correlation trends of previous studies of GCs of similar metallicity. We finally explore the abundances ..., Comment: 27 pages, 10 figures, 5 tables. Abridged abstract. Accepted for publication in Astronomy & Astrophysics (A&A)
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- 2021
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46. Temporal evolution of small-scale internetwork magnetic fields in the solar photosphere (Corrigendum)
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R. J. Campbell, Michail Mathioudakis, Manuel Collados, Chris J. Nelson, David Kuridze, Aaron Reid, A. Asensio Ramos, and P. H. Keys
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Physics ,Photosphere ,Line-of-sight ,Space and Planetary Science ,Astronomy and Astrophysics ,Geometry ,Scale (descriptive set theory) ,Astrophysics ,Table (information) ,Column (database) ,Row ,Typographical error ,Magnetic field - Abstract
We correct a typographical error in the original paper. Figures 10, 12, 14, 15, and 16 contain a table in the top right panel with four columns and four rows of values. The line of sight velocity, vLOS, values for scheme 1 inversions (in the fourth row, first column and second column) are inserted the wrong way around. The values themselves are correct, but printed in the wrong column. All other values in the tables remain unaffected, and none of the paper's discussions or conclusions are impacted. We provide corrected versions of Figs. 10, 12, 14, 15, and 16 in Figs. 1, 2, 3, 4, and 5, respectively.
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- 2021
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47. ALMA 870 μm continuum observations of HD 100546
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Claudia Toci, Davide Fedele, Luke T. Maud, and Giuseppe Lodato
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Physics ,Spiral galaxy ,media_common.quotation_subject ,Image (category theory) ,Giant planet ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,01 natural sciences ,Orbit ,Astrophysics - Solar and Stellar Astrophysics ,Space and Planetary Science ,Planet ,0103 physical sciences ,Astrophysics::Earth and Planetary Astrophysics ,Continuum (set theory) ,Eccentricity (behavior) ,010306 general physics ,Protoplanet ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Astrophysics - Earth and Planetary Astrophysics ,media_common - Abstract
This paper reports on a new analysis of archival ALMA $870\,\mu$m dust continuum observations. Along with the previously observed bright inner ring ($r \sim 20-40\,$au), two addition substructures are evident in the new continuum image: a wide dust gap, $r \sim 40-150\,$au, and a faint outer ring ranging from $r \sim 150\,$au to $r \sim 250\,$au and whose presence was formerly postulated in low-angular-resolution ALMA cycle 0 observations but never before observed. Notably, the dust emission of the outer ring is not homogeneous, and it shows two prominent azimuthal asymmetries that resemble an eccentric ring with eccentricity $e = 0.07 $. The characteristic double-ring dust structure of HD 100546 is likely produced by the interaction of the disk with multiple giant protoplanets. This paper includes new smoothed-particle-hydrodynamic simulations with two giant protoplanets, one inside of the inner dust cavity and one in the dust gap. The simulations qualitatively reproduce the observations, and the final masses and orbital distances of the two planets in the simulations are 3.1 $M_{J}$ at 15 au and 8.5 $M_{J}$ at 110 au, respectively. The massive outer protoplanet substantially perturbs the disk surface density distribution and gas dynamics, producing multiple spiral arms both inward and outward of its orbit. This can explain the observed perturbed gas dynamics inward of 100 au as revealed by ALMA observations of CO. Finally, the reduced dust surface density in the $\sim 40-150\,$au dust gap can nicely clarify the origin of the previously detected H$_2$O gas and ice emission., Comment: Accepted for publication
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- 2021
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48. Variable stars in the VVV globular clusters
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Julio A. Carballo-Bello, Karla Peña Ramírez, Jura Borissova, Maren Hempel, Dante Minniti, Rodrigo Contreras Ramos, Zhen Guo, José G. Fernández-Trincado, Doug Geisler, Tali Palma, Eamonn Kerins, R. K. Saito, Felipe Gran, Leigh C. Smith, Javier Alonso-García, E. R. Garro, Márcio Catelan, Carlos E. Ferreira Lopes, Sebastián Ramírez Alegría, Philip W. Lucas, and Camila Navarrete
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media_common.quotation_subject ,Milky Way ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,variables: RR Lyrae [Stars] ,RR Lyrae variable ,01 natural sciences ,variables: general [Stars] ,0103 physical sciences ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Solar and Stellar Astrophysics (astro-ph.SR) ,media_common ,Physics ,Extinction ,010308 nuclear & particles physics ,Astronomy and Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Photometry (astronomy) ,Variable (computer science) ,Astrophysics - Solar and Stellar Astrophysics ,Space and Planetary Science ,Sky ,Astrophysics of Galaxies (astro-ph.GA) ,Globular cluster ,general [Globular clusters] ,Variable star - Abstract
The Galactic globular clusters (GGCs) located in the inner regions of the Milky Way suffer from high extinction that makes their observation challenging. The VVV survey provides a way to explore these GGCs in the near-infrared where extinction effects are highly diminished. We conduct a search for variable stars in several inner GGCs, taking advantage of the unique multi-epoch, wide-field, near-infrared photometry provided by the VVV survey. We are especially interested in detecting classical pulsators that will help us constrain the physical parameters of these GGCs. In this paper, the second of a series, we focus on NGC6656 (M22), NGC6626 (M28), NGC6569, and NGC6441; these four massive GGCs have known variable sources, but quite different metallicities. We also revisit 2MASS-GC02 and Terzan10, the two GGCs studied in the first paper of this series. We present an improved method and a new parameter that efficiently identify variable candidates in the GGCs. We also use the proper motions of those detected variable candidates and their positions in the sky and in the color-magnitude diagrams to assign membership to the GGCs. We identify and parametrize in the near-infrared numerous variable sources in the studied GGCs, cataloging tens of previously undetected variable stars. We recover many known classical pulsators in these clusters, including the vast majority of their fundamental mode RR Lyrae. We use these pulsators to obtain distances and extinctions toward these objects. Recalibrated period-luminosity-metallicity relations for the RR Lyrae bring the distances to these GGCs to a closer agreement with those reported by Gaia, except for NGC6441. Recovered proper motions for these GGCs also agree with those reported by Gaia, except for 2MASS-GC02, the most reddened GGC in our sample, where the VVV near-infrared measurements provide a more accurate determination of its proper motions., Comment: Accepted for publication in A&A, 18 pages, 14 Figures, 9 Tables
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- 2021
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49. Systematic Kmtnet Planetary Anomaly Search V. Complete Sample of 2018 Prime-Field
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Andrew Gould, Cheongho Han, Weicheng Zang, Hongjing Yang, Kyu-Ha Hwang, Andrzej Udalski, Ian A. Bond, Michael D. Albrow, Sun-Ju Chung, Youn Kil Jung, Yoon-Hyun Ryu, In-Gu Shin, Yossi Shvartzvald, Jennifer C. Yee, Sang-Mok Cha, Dong-Jin Kim, Hyoun-Woo Kim, Seung-Lee Kim, Chung-Uk Lee, Dong-Joo Lee, Yongseok Lee, Byeong-Gon Park, Richard W. Pogge, Przemek Mróz, Michał K. Szymański, Jan Skowron, Radek Poleski, Igor Soszyński, Paweł Pietrukowicz, Szymon Kozłowski, Krzysztof Ulaczyk, Krzysztof A. Rybicki, Patryk Iwanek, Marcin Wrona, Fumio Abe, Richard Barry, David P. Bennett, Aparna Bhattacharya, Hirosame Fujii, Akihiko Fukui, Yuki Hirao, Stela Ishitani Silva, Greg Olmschenk, and Aikaterini Vandorou
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Astronomy ,Astrophysics - Abstract
We complete the analysis of all 2018 prime-field microlensing planets identified by the Korea Microlensing Telescope Network (KMTNet) Anomaly Finder. Among the ten previously unpublished events with clear planetary solutions, eight are either unambiguously planetary or are very likely to be planetary in nature: OGLE-2018-BLG-1126, KMT-2018-BLG-2004, OGLE-2018-BLG-1647, OGLE-2018-BLG-1367, OGLE-2018-BLG-1544, OGLE-2018-BLG-0932, OGLE-2018-BLG-1212, and KMT-2018-BLG-2718. Combined with the four previously published new Anomaly Finder events and 12 previously published (or in preparation) planets that were discovered by eye, this makes a total of 24 2018 prime-field planets discovered or recovered by Anomaly Finder. Together with a paper in preparation on 2018 subprime planets, this work lays the basis for the first statistical analysis of the planet mass-ratio function based on planets identified in KMTNet data. By systematically applying the heuristic analysis to each event, we identified the small modification in their formalism that is needed to unify the so-called close-wide and inner-outer degeneracies.
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- 2022
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50. The volumetric star formation law in the Milky Way
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Carlo Nipoti, Filippo Fraternali, G. Iorio, Gabriele Pezzulli, Antonino Marasco, Cecilia Bacchini, Bacchini, C., Fraternali, F., Pezzulli, G., Marasco, A., Iorio, G., Nipoti, C., and Astronomy
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DISC GALAXIES ,CHEMICAL EVOLUTION ,Astrophysics ,01 natural sciences ,law.invention ,star ,FORMATION THRESHOLDS ,galaxies ,010303 astronomy & astrophysics ,Galaxy: structure ,Physics ,formation ,disk ,ISM: structure ,Galaxies: star formation ,Galaxy: disk [Stars] ,Scale height ,MOLECULAR GAS ,Astrophysics::Earth and Planetary Astrophysics ,RADIAL-DISTRIBUTION ,stars ,SCHMIDT-LAW ,Milky Way ,Stars: formation ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Disc galaxy ,star formation ,Galaxy: disk ,3-DIMENSIONAL DISTRIBUTION ,0103 physical sciences ,Galaxy formation and evolution ,DARK-MATTER ,NEARBY GALAXIES ,structure ,Disc ,Astrophysics::Galaxy Astrophysics ,ISM ,010308 nuclear & particles physics ,Star formation ,galaxie ,Astronomy and Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,Law ,Hydrostatic equilibrium ,H-I - Abstract
Several open questions on galaxy formation and evolution have their roots in the lack of a universal star formation law, that could univocally link the gas properties, e.g. its density, to the star formation rate (SFR) density. In a recent paper, we used a sample of nearby disc galaxies to infer the volumetric star formation (VSF) law, a tight correlation between the gas and the SFR volume densities derived under the assumption of hydrostatic equilibrium for the gas disc. However, due to the dearth of information about the vertical distribution of the SFR in these galaxies, we could not find a unique slope for the VSF law, but two alternative values. In this paper, we use the scale height of the SFR density distribution in our Galaxy adopting classical Cepheids (age$\lesssim 200$ Myr) as tracers of star formation. We show that this latter is fully compatible with the flaring scale height expected from gas in hydrostatic equilibrium. These scale heights allowed us to convert the observed surface densities of gas and SFR into the corresponding volume densities. Our results indicate that the VSF law $\rho_\mathrm{SFR} \propto \rho_\mathrm{gas}^\alpha$ with $\alpha \approx 2$ is valid in the Milky Way as well as in nearby disc galaxies., Comment: 9 pages, 4 figures, + 4 pages of Appendix, accepted by A&A
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- 2019
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