259 results on '"BOOTES"'
Search Results
2. THE BOOTES NETWORK IN THE GRAVITATIONAL WAVE ERA
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Y. D. Hu, S. Guziy, E. J. Fernandez-García, Yu-Xin Xin, W. H. Lee, I. Carrasco-Garcia, D. Hiriart, A. J. Castro-Tirado, D. Xiong, J. Bai Yunnan, Seok Ho Jeong, C. Perez del Pulgar, R. Querel, Inkyu Park, M. D. Caballero-Garcia, X. Y. Li, C. Wang, X. H. Zhao, A. Castellon, and Yi-Zhong Fan
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Physics ,General Relativity and Quantum Cosmology ,Gravitational wave ,Astrophysics::Instrumentation and Methods for Astrophysics ,Astronomy ,BOOTES ,General Medicine - Abstract
The Burst Optical Observer and Transient Exploring System (BOOTES) is a world-wide automatic telescope network which aims to repaid follow-up of transient and astrophysical sources in the sky for which the first station was installed in 1998. With the advent in 2015 of the LIGO/Virgo interferometers, as part of the new generation of detectors designed for the detection of the signal of gravitational waves, a new window to explore the Universe has been opened. Here we present the status of the BOOTES network, the related strategies regarding the follow-up of gravitational wave events and the developments in the Gravitational Wave Era. Some preliminary results regarding the BOOTES follow-up observations are presented.
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- 2021
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3. Peculiar motions of galaxy clusters in the regions of the Corona Borealis, Bootes, Z 5029/A 1424, A 1190, A 1750/A 1809 superclusters of galaxies.
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Kopylova, F. and Kopylov, A.
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GALAXY clusters , *CORONA Borealis (Constellation) , *VELOCITY , *COSMIC background radiation , *GRAVITATIONAL interactions - Abstract
We present results of the study of peculiar motions of 57 clusters and groups of galaxies in the regions of the Corona Borealis (CrB), Bootes (Boo), Z5029/A1424, A1190, A1750/A1809 superclusters of galaxies and the galaxy clusters located beyond massive structures (0.05 < z < 0.10). Using the SDSS (Data Release 8) data, a sample of early-type galaxies was compiled in the systems under study, their fundamental planes were built, and relative distances and peculiar velocities were determined. Within the galaxy superclusters, significant peculiar motions along the line of sight are observed with rms deviations of 652 ± 50 kms-in CrB, 757 ± 70 kms-in Boo. In the most massive A2065 cluster in the CrB supercluster, no peculiar velocity was found. Peculiar motions of the other galaxy clusters can be caused by their gravitational interaction both with A2065 and with the A2142 supercluster. It has been found that there are two superclusters projected onto each other in the region of the Bootes supercluster with a radial velocity difference of about 4000 kms. In the Z 5029/A1424 supercluster near the rich Z5029 cluster, the most considerable peculiar motions with a rms deviations of 1366 ± 170 kms are observed. The rms deviations of peculiar velocities of 20 clusters that do not belong to large-scale structures is equal to 0 ± 20 kms. The whole sample of the clusters under study has the mean peculiar velocity equal to 83 ± 130 kms relative to the cosmic microwave background. [ABSTRACT FROM AUTHOR]
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- 2017
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4. Contribution of Type Ia Supernovae to the Chemical Enrichment of the Ultra-Faint Dwarf Galaxy Boötes I
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Lyudmila Mashonkina, Tatyana Sitnova, Yu. V. Pakhomov, Pascale Jablonka, Galaxies, Etoiles, Physique, Instrumentation (GEPI), 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)-Centre National de la Recherche Scientifique (CNRS)
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FOS: Physical sciences ,chemistry.chemical_element ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,01 natural sciences ,Spectral line ,0103 physical sciences ,Astrophysics::Solar and Stellar Astrophysics ,010303 astronomy & astrophysics ,Solar and Stellar Astrophysics (astro-ph.SR) ,ComputingMilieux_MISCELLANEOUS ,Astrophysics::Galaxy Astrophysics ,Dwarf galaxy ,[PHYS]Physics [physics] ,Physics ,010308 nuclear & particles physics ,Astronomy and Astrophysics ,Barium ,BOOTES ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Nickel ,Stars ,Supernova ,Astrophysics - Solar and Stellar Astrophysics ,chemistry ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,Astrophysics::Earth and Planetary Astrophysics ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] - Abstract
For three stars in the ultra-faint dwarf (UFD) galaxy Bootes I we have determined the atmospheric parameters, performed a new reduction of high-resolution spectra from the Subaru archive, and derived the abundances of eight chemical elements without using the LTE assumption. As a result, among the galaxies of its class Bootes I now has the largest sample of stars (11) with a homogeneous set of atmospheric parameters and chemical abundances, and this makes it the most promising for studying the chemical evolution of UFD galaxies. We show that in the range -3, Comment: 10 pages, 9 figures, 7 tables
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- 2019
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5. The LOFAR Two-meter Sky Survey: Deep Fields Data Release 1
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K. C. Chambers, T. Ploeckinger, M. E. Huber, Rachel Cochrane, L. Wang, M. J. Rosenthal, Isabella Prandoni, A. Wo łowska, R. Kondapally, Rosita Paladino, B. Nikiel-Wroczy ński, Philip Best, H. J. A. R öttgering, Timothy W. Shimwell, Martin J. Hardcastle, E. A. Magnier, A. Shulevski, Kenneth Duncan, J. Sabater, V. H. Mahatma, Dominik J. Schwarz, J. H. Croston, Daniel J. Smith, Magdalena Kunert-Bajraszewska, I. McCheyne, D. Nisbet, R. I. J. Mostert, J. D. Wagenveld, Michael J. I. Brown, Matt J. Jarvis, Beatriz Mingo, Wendy L. Williams, S. P. OŚullivan, G. G ürkan, M. Brienza, Arti Goyal, Rebecca A. A. Bowler, M. A. Garrett, M. Br üggen, M. Bondi, M. Bonato, C. Tasse, Marek Jamrozy, Kondapally, R., Best, P. N., Hardcastle, M. J., Nisbet, D., Bonato, M., Sabater, J., Duncan, K. J., McCheyne, I., Cochrane, R. K., Bowler, R. A. A., Williams, W. L., Shimwell, T. W., Tasse, C., Croston, J. H., Goyal, A., Jamrozy, M., Jarvis, M. J., Mahatma, V. H., Röttgering, H. J. A., Smith, D. J. B., Wołowska, A., Bondi, M., Brienza, M., Brown, M. J. I., Brüggen, M., Chambers, K., Garrett, M. A., Gürkan, G., Huber, M., Kunert-Bajraszewska, M., Magnier, E., Mingo, B., Mostert, R., Nikiel-Wroczyński, B., O’Sullivan, S. P., Paladino, R., Ploeckinger, T., Prandoni, I., Rosenthal, M. J., Schwarz, D. J., Shulevski, A., Wagenveld, J. D., Wang, L., Galaxies, Etoiles, Physique, Instrumentation (GEPI), 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)-Centre National de la Recherche Scientifique (CNRS), and Astronomy
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catalog ,Active galactic nucleus ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,media_common.quotation_subject ,Astrophysics::High Energy Astrophysical Phenomena ,Population ,FOS: Physical sciences ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Photometry (optics) ,surveys ,Astrophysics - Astrophysics of Galaxie ,0103 physical sciences ,survey ,Astrophysics - Cosmology and Nongalactic Astrophysic ,education ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,media_common ,Physics ,High Energy Astrophysical Phenomena (astro-ph.HE) ,radio continuum: galaxies ,education.field_of_study ,010308 nuclear & particles physics ,Astrophysics::Instrumentation and Methods for Astrophysics ,Astronomy and Astrophysics ,BOOTES ,LOFAR ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Redshift ,galaxies [radio continuum] ,Space and Planetary Science ,Sky ,Astrophysics of Galaxies (astro-ph.GA) ,radio continuum: galaxie ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,Astrophysics - High Energy Astrophysical Phenomena ,catalogs ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We present the source associations, cross-identifications, and multi-wavelength properties of the faint radio source population detected in the deep tier of the LOFAR Two Metre Sky Survey (LoTSS): the LoTSS Deep Fields. The first LoTSS Deep Fields data release consists of deep radio imaging at 150~MHz of the ELAIS-N1, Lockman Hole, and Bo\"{o}tes fields, down to RMS sensitives of around 20, 22, and 32$~\mu$Jy\,beam$^{-1}$, respectively. These fields are some of the best studied extra-galactic fields in the northern sky, with existing deep, wide-area panchromatic photometry from X-ray to infrared wavelengths, covering a total of $\approx$~26~\mbox{deg$^{2}$}. We first generated improved multi-wavelength catalogues in ELAIS-N1 and Lockman Hole; combined with the existing catalogue for Bo\"{o}tes, we present forced, matched aperture photometry for over 7.2 million sources across the three fields. We identified multi-wavelength counterparts to the radio detected sources, using a combination of the Likelihood Ratio method and visual classification, which greatly enhances the scientific potential of radio surveys and allows for the characterisation of the photometric redshifts and the physical properties of the host galaxies. The final radio-optical cross-matched catalogue consists of 81\,951 radio-detected sources, with counterparts identified and multi-wavelength properties presented for 79\,820 ($>$97\%) sources. We also examine the properties of the host galaxies, and through stacking analysis find that the radio population with no identified counterpart is likely dominated by AGN at $z\sim3-4$. This dataset contains one of the largest samples of radio-selected star-forming galaxies and active galactic nuclei (AGN) at these depths, making it ideal for studying the history of star-formation, and the evolution of galaxies and AGN across cosmic time., Comment: 34 pages, 14 figures and 14 tables. Accepted for publication in A&A special issue. This paper is part of the 1st data release of the LoTSS Deep Fields. Electronic data catalogues will be made available on journal publication
- Published
- 2021
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6. Ultra-faint dwarf galaxies: unveiling the minimum mass of the first stars
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Martina Rossi, Stefania Salvadori, and A. Skuladottir
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Physics ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,Initial mass function ,FOS: Physical sciences ,Minimum mass ,Astronomy and Astrophysics ,BOOTES ,Astrophysics ,Expected value ,Astrophysics - Astrophysics of Galaxies ,Stars ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,Magnitude (astronomy) ,Eridanus ,Dwarf galaxy ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
The non-detection of zero-metallicity stars in ultra-faint dwarf galaxies (UFDs) can be used to constrain the Initial Mass Function (IMF) of the first (PopIII) stars by means of a statistical comparison between available data and predictions from chemical evolution models. To this end we develop a model that follows the formation of isolated UFDs, calibrated to best reproduce the available data for the best studied system: Bo��tes I. Our statistical approach shows that UFDs are the best suitable systems to study the implications of the persisting non-detection of zero-metallicity stars on the PopIII IMF, i.e. its shape, the minimum mass ($m_{min}$), and the characteristic mass ($m_{ch}$). We show that accounting for the incomplete sampling of the IMF is essential to compute the expected number of long-lived PopIII stars in inefficiently star-forming UFDs. By simulating the Color Magnitude Diagram of Bo��tes I, and thus take into account the mass-range of the observed stars, we can obtain even tighter constrains on $m_{min}$. By exploiting the 96 stars with measured metallicities ($\rm i < 19$) in the UFDs represented by our model, we demonstrate that: $m_{ch} > 1 \rm M_{\odot}$ or $m_{min} > 0.8 \rm M_{\odot}$ at $99\%$ confidence level. This means that a present day IMF for PopIII stars is excluded by our model, and a top-heavy PopIII IMF is strongly favoured. We can limit $m_{min} > 0.8 \rm M_{\odot}$ independent of the PopIII IMF shape by targeting the four UFDs Bo��tes I, Hercules, Leo IV and Eridanus II with future generation instruments, such as ELT/MOSAIC ($\rm i < 25$), which can provide samples of >10\,000 stars., Accepted by MNRAS
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- 2021
7. The LOFAR Two-meter Sky Survey: Deep Fields Data Release 1
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Matteo Bonato, Isabella Prandoni, Aleksandar Shulevski, H. J. A. Röttgering, R. J. van Weeren, G. Calistro-Rivera, P. N. Best, G. Brunetti, A. Botteon, J. Sabater, Martin J. Hardcastle, Shane O'Sullivan, M. Bondi, Cyril Tasse, Leah K. Morabito, Subhash C. Mandal, L. Bester, Matt J. Jarvis, Yves Wiaux, Oleg Smirnov, M. A. Garrett, Timothy W. Shimwell, F. de Gasperin, Audrey Repetti, R. Kondapally, G. Gürkan, Wendy L. Williams, B. Hugo, Dominik J. Schwarz, Marcus Brüggen, E. Retana-Montenegro, Krzysztof T. Chyzy, Galaxies, Etoiles, Physique, Instrumentation (GEPI), 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)-Centre National de la Recherche Scientifique (CNRS), Istituto di Radioastronomia [Bologna] (IRA), Istituto Nazionale di Astrofisica (INAF), School of Mathematical and Computer Sciences (MATHEMATICS DEPARTMENT OF HERIOT-WATT UNIVERSITY), Heriot-Watt University [Edinburgh] (HWU), and School of Engineering and Physical Sciences [Edinburgh] (EPS-HWU)
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Astrophysics - instrumentation and methods for astrophysics ,Phased array ,media_common.quotation_subject ,galaxies: active ,techniques: image processing ,galaxies: starburst ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Noise (electronics) ,surveys ,0103 physical sciences ,Calibration ,010303 astronomy & astrophysics ,High dynamic range ,media_common ,Remote sensing ,Physics ,radio continuum: galaxies ,image processing [techniques] ,010308 nuclear & particles physics ,starburst [galaxies] ,Astrophysics::Instrumentation and Methods for Astrophysics ,Astronomy and Astrophysics ,BOOTES ,LOFAR ,galaxies [radio continuum] ,interferometric [techniques] ,Space and Planetary Science ,Sky ,techniques: interferometric ,active [galaxies] ,Antenna (radio) ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] - Abstract
The Low Frequency Array (LOFAR) is an ideal instrument to conduct deep extragalactic surveys. It has a large field of view and is sensitive to large-scale and compact emission. It is, however, very challenging to synthesize thermal noise limited maps at full resolution, mainly because of the complexity of the low-frequency sky and the direction dependent effects (phased array beams and ionosphere). In this first paper of a series, we present a new calibration and imaging pipeline that aims at producing high fidelity, high dynamic range images with LOFAR High Band Antenna data, while being computationally efficient and robust against the absorption of unmodeled radio emission. We apply this calibration and imaging strategy to synthesize deep images of the Boötes and Lockman Hole fields at ~150 MHz, totaling ~80 and ~100 h of integration, respectively, and reaching unprecedented noise levels at these low frequencies of ≲30 and ≲23μJy beam−1in the inner ~3 deg2. This approach is also being used to reduce the LOTSS-wide data for the second data release.
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- 2021
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8. The bright end of the infrared luminosity functions and the abundance of hyperluminous infrared galaxies
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C. Tasse, Rachel Cochrane, W. J. Pearson, Timothy W. Shimwell, Matteo Bonato, M. Bondi, Katarzyna Małek, P. Haskell, Lingyu Wang, G. Gürkan, F. Gao, Martin J. Hardcastle, Huub Röttgering, Kenneth Duncan, Mattia Vaccari, R. Kondapally, I. McCheyne, Duncan Farrah, Philip Best, Daniel J. Smith, Isabella Prandoni, J. Sabater, Wendy L. Williams, SRON Netherlands Institute for Space Research (SRON), Kapteyn Astronomical Institute [Groningen], University of Groningen [Groningen], Galaxies, Etoiles, Physique, Instrumentation (GEPI), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Astronomy, and Kapteyn Astronomical Institute
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Galaxies: abundances ,Astrophysics - astrophysics of galaxies ,Population ,FOS: Physical sciences ,Astrophysics ,01 natural sciences ,Radio continuum: galaxies ,Luminosity ,Galaxies: luminosity function ,0103 physical sciences ,education ,010303 astronomy & astrophysics ,Photometric redshift ,Luminous infrared galaxy ,Physics ,education.field_of_study ,[SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph] ,010308 nuclear & particles physics ,Galaxies: high-redshift ,Galaxies: evolution ,Astronomy and Astrophysics ,BOOTES ,LOFAR ,Infrared: galaxies ,Galaxy ,13. Climate action ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,Mass function ,Spectral energy distribution - Abstract
We provide the most accurate estimate yet of the bright end of the infrared (IR) luminosity functions (LFs) and the abundance of hyperluminous IR galaxies (HLIRGs) with IR luminosities > 10^13 L_solar, thanks to the combination of the high sensitivity, angular resolution, and large area of the LOFAR Deep Fields, which probes an unprecedented dynamic range of luminosity and volume. We cross-match Herschel sources and LOFAR sources in Bootes (8.63 deg^2), Lockman Hole (10.28 deg^2), and ELAIS-N1 (6.74 deg^2) with rms sensitivities of around 32, 22, and 20 mJy per beam, respectively. We divide the matched samples into unique and multiple categories. For the multiple matches, we de-blend the Herschel fluxes using the LOFAR positions and the 150-MHz flux densities as priors. We perform spectral energy distribution (SED) fitting, combined with multi-wavelength counterpart identifications and photometric redshift estimates, to derive IR luminosities. The depth of the LOFAR data allows us to identify highly complete (around 92% completeness) samples of bright Herschel sources with a simple selection based on the 250 micron flux density (45, 40, and 35 mJy in Bootes, Lockman Hole, and ELAIS-N1, respectively). Most of the bright Herschel sources fall into the unique category (i.e. a single LOFAR counterpart). For the multiple matches, there is excellent correspondence between the radio emission and the far-IR emission. We find a good agreement in the IR LFs with a previous study out to z around 6 which used de-blended Herschel data. Our sample gives the strongest and cleanest indication to date that the population of HLIRGs has surface densities of around 5 to 18 / deg^2 (with variations due to a combination of the applied flux limit and cosmic variance) and an uncertainty of a factor of 2. In comparison, the GALFORM semi-analytic model significantly under-predicts the abundance of HLIRGs., 16 pages, 11 figures, accepted for publication in A&A as part of the LOFAR Deep Fields Paper Splash
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- 2021
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9. A new distant giant radio galaxy in the Boötes field serendipitously detected by Chandra
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Annalisa Celotti, Emily Moravec, Wendy L. Williams, Alberto Masini, and Paola Grandi
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Physics ,Galaxies: general ,Field (physics) ,010308 nuclear & particles physics ,Radio galaxy ,Astronomy and Astrophysics ,BOOTES ,Astrophysics ,Galaxies: active ,01 natural sciences ,Astrophysics - high energy astrophysical phenomena ,Radio continuum: galaxies ,X-rays: galaxies ,Space and Planetary Science ,Galaxies: jets ,0103 physical sciences ,010303 astronomy & astrophysics - Abstract
Giant Radio Galaxies (GRGs) are the largest single structures in the Universe. Exhibiting extended radio morphology, their projected sizes range from 0.7 Mpc up to 4.9 Mpc. LOFAR has opened a new window on the discovery and investigation of GRGs and, despite the hundreds that are today known, their main growth catalyst is still debated. One natural explanation for the exceptional size of GRGs is their old age. In this context, hard X-ray selected GRGs show evidence of restarting activity, with the giant radio lobes being mostly disconnected from the nuclear source, if any. In this paper, we present the serendipitous discovery of a distant ($z=0.629$), medium X-ray selected GRG in the Bo\"otes field. High-quality, deep Chandra and LOFAR data allow a robust study of the connection between the nucleus and the lobes, at a larger redshift so far inaccessible to coded-mask hard X-ray instruments. The radio morphology of the GRG presented in this work does not show evidence for restarted activity, and the nuclear radio core spectrum does not appear to be GPS-like. On the other hand, the X-ray properties of the new GRG are perfectly consistent with the ones previously studied with Swift/BAT and INTEGRAL at lower redshift. In particular, the bolometric luminosity measured from the X-ray spectrum is a factor of six larger than the one derived from the radio lobes, although the large uncertainties make them formally consistent at $1\sigma$. Finally, the moderately dense environment around the GRG, traced by the spatial distribution of galaxies, supports recent findings that the growth of GRGs is not primarily driven by underdense environments., Comment: 8 pages, 5 figures. Accepted for publication in A&A
- Published
- 2021
10. Neutron-capture elements in dwarf galaxies III. A homogenized analysis of 13 dwarf spheroidal and ultra-faint galaxies
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Michael Hanke, Camilla Juul Hansen, Á. Skúladóttir, Almudena Arcones, Eva K. Grebel, and Moritz Reichert
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MILKY-WAY SATELLITE ,Ursa Major ,Stellar mass ,dwarf [galaxies] ,Metallicity ,fundamental parameters [stars] ,FOS: Physical sciences ,Ursa Minor ,CHEMICAL EVOLUTION ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,LTE LINE FORMATION ,CORE-COLLAPSE SUPERNOVAE ,0103 physical sciences ,abundances [galaxies] ,Astrophysics::Solar and Stellar Astrophysics ,GIANT BRANCH STARS ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,evolution [galaxies] ,Dwarf galaxy ,Physics ,EXTREMELY METAL-POOR ,010308 nuclear & particles physics ,R-PROCESS ,Astronomy and Astrophysics ,BOOTES ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,abundances [stars] ,Supernova ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,TRANSITION-PROBABILITIES ,S-PROCESS ,catalogs ,MULTIELEMENT ABUNDANCE MEASUREMENTS - Abstract
Context. We present a large homogeneous set of stellar parameters and abundances across a broad range of metallicities, involving 13 classical dwarf spheroidal (dSph) and ultra-faint dSph (UFD) galaxies. In total, this study includes 380 stars in Fornax, Sagittarius, Sculptor, Sextans, Carina, Ursa Minor, Draco, Reticulum II, Bootes I, Ursa Major II, Leo I, Segue I, and Triangulum II. This sample represents the largest, homogeneous, high-resolution study of dSph galaxies to date. Aims. With our homogeneously derived catalog, we are able to search for similar and deviating trends across different galaxies. We investigate the mass dependence of the individual systems on the production of α-elements, but also try to shed light on the long-standing puzzle of the dominant production site of r-process elements. Methods. We used data from the Keck observatory archive and the ESO reduced archive to reanalyze stars from these 13 classical dSph and UFD galaxies. We automatized the step of obtaining stellar parameters, but ran a full spectrum synthesis (1D, local thermal equilibrium) to derive all abundances except for iron to which we applied nonlocal thermodynamic equilibrium corrections where possible. Results. The homogenized set of abundances yielded the unique possibility of deriving a relation between the onset of type Ia supernovae and the stellar mass of the galaxy. Furthermore, we derived a formula to estimate the evolution of α-elements. This reveals a universal relation of these systems across a large range in mass. Finally, we show that between stellar masses of 2.1 × 107 M⊙ and 2.9 × 105 M⊙, there is no dependence of the production of heavy r-process elements on the stellar mass of the galaxy. Conclusions. Placing all abundances consistently on the same scale is crucial to answering questions about the chemical history of galaxies. By homogeneously analyzing Ba and Eu in the 13 systems, we have traced the onset of the s-process and found it to increase with metallicity as a function of the galaxy’s stellar mass. Moreover, the r-process material correlates with the α-elements indicating some coproduction of these, which in turn would point toward rare core-collapse supernovae rather than binary neutron star mergers as a host for the r-process at low [Fe/H] in the investigated dSph systems.
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- 2020
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11. Faint Stars in a Faint Galaxy: I. Ultra Deep Photometry of the Bo\'otes I Ultra Faint Dwarf Galaxy
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Rosemary F. G. Wyse, Imants Platais, Roberto J. Avila, Carrie Filion, and Vera Kozhurina-Platais
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Physics ,Astronomy ,Local Group ,Astronomy and Astrophysics ,BOOTES ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Stars ,Photometry (astronomy) ,Space and Planetary Science ,Astrophysics::Solar and Stellar Astrophysics ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics - Instrumentation and Methods for Astrophysics ,Astrophysics::Galaxy Astrophysics ,Dwarf galaxy - Abstract
We present an analysis of new extremely deep images of the resolved stellar population of the Bo\"otes I ultra faint dwarf spheroidal galaxy. These new data were taken with the Hubble Space Telescope, using the Advanced Camera for Surveys (Wide Field Camera) and Wide Field Camera 3 (UVIS), with filters F606W and F814W (essentially V and I), as part of a program to derive the low-mass stellar initial mass function in this galaxy. We compare and contrast two approaches to obtaining the stellar photometry, namely ePSF and DAOPHOT. We identify likely members of Bo\"otes I based on the location of each star on the color-magnitude diagram, obtained with the DAOPHOT photometry from the ACS/WFC data. The probable members lie close to stellar isochrones that were chosen to encompass the known metallicity distribution derived from spectroscopic data of brighter radial-velocity member stars and are consistent with the main-sequence turnoff. The resulting luminosity function of the Bo\"otes I galaxy has a 50% completeness limit of 27.4 in F814W and 28.2 in F606W (Vega magnitude system), which corresponds to a limiting stellar mass of $\le 0.3 M_\odot$., Comment: 21 pages, 15 figures, 2 tables; accepted for publication in ApJ
- Published
- 2020
12. Gaia RR Lyrae Stars in Nearby Ultra-Faint Dwarf Satellite Galaxies
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Alistair R. Walker, A. Katherina Vivas, and C. E. Martínez-Vázquez
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Ursa Major ,media_common.quotation_subject ,FOS: Physical sciences ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,RR Lyrae variable ,01 natural sciences ,0103 physical sciences ,Satellite galaxy ,Astrophysics::Solar and Stellar Astrophysics ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Dwarf galaxy ,media_common ,Physics ,010308 nuclear & particles physics ,Astrophysics::Instrumentation and Methods for Astrophysics ,Astronomy and Astrophysics ,BOOTES ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Space and Planetary Science ,Sky ,Astrophysics of Galaxies (astro-ph.GA) ,Astrophysics::Earth and Planetary Astrophysics ,Variable star - Abstract
We search for RR Lyrae stars in 27 nearby ($, Accepted for publication in ApJSS
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- 2020
13. Chemical evolution of ultrafaint dwarf galaxies: testing the IGIMF
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Marco Palla, Francesca Matteucci, E. Lacchin, Fiorenzo Vincenzo, Lacchin, E., Matteucci, F., Vincenzo, F., and Palla, M.
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Initial mass function ,dwarf [galaxies] ,formation [galaxies] ,Stellar mass ,stars: abundances ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Type (model theory) ,abundance [stars] ,01 natural sciences ,Galactic halo ,0103 physical sciences ,galaxies: formation ,galaxies: abundances ,galaxies: dwarf ,galaxies: evolution ,Local Group ,Astrophysics - Astrophysics of Galaxies ,010303 astronomy & astrophysics ,evolution [galaxies] ,Astrophysics::Galaxy Astrophysics ,Dwarf galaxy ,Physics ,010308 nuclear & particles physics ,Star formation ,Astronomy and Astrophysics ,BOOTES ,Galaxy ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,abundance [galaxies] - Abstract
We test the integrated galactic initial mass function (IGIMF) on the chemical evolution of 16 ultra-faint dwarf (UFD) galaxies discussing in detail the results obtained for three of them: Bo\"otes I, Bo\"otes II and Canes Venatici I, taken as prototypes of the smallest and the largest UFDs. These objects have very small stellar masses ($\sim 10^3-10^4 \mathrm{M_{\odot}}$) and quite low metallicities ([Fe/H]$, Comment: Accepted for publication in MNRAS
- Published
- 2020
14. Space Variant PSF – Deconvolution of Wide-Field Astronomical Images
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M. Řeřábek
- Subjects
high order aberrations ,PSF ,UWFC ,BOOTES ,Zernike ,Seidel ,LSI ,LSV ,deconvolution ,image processing ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
The properties of UWFC (Ultra Wide-Field Camera) astronomical systems along with specific visual data in astronomical images contribute to a comprehensive evaluation of the acquired image data. These systems contain many different kinds of optical aberrations which have a negatively effect on image quality and imaging system transfer characteristics, and reduce the precision of astronomical measurement. It is very important to figure two main questions out. At first: In which astrometric depend on optical aberrations? And at second: How optical aberrations affect the transfer characteristics of the whole optical system. If we define the PSF (Point Spread Function) [2] of an optical system, we can use some suitable methods for restoring the original image. Optical aberration models for LSI/LSV (Linear Space Invariant/Variant) [2] systems are presented in this paper. These models are based on Seidel and Zernike approximating polynomials [1]. Optical aberration models serve as suitable tool for estimating and fitting the wavefront aberration of a real optical system. Real data from the BOOTES (Burst Observer and Optical Transient Exploring System) experiment is used for our simulations. Problems related to UWFC imaging systems, especially a restoration method in the presence of space variant PSF are described in this paper. A model of the space variant imaging system and partially of the space variant optical system has been implemented in MATLAB. The “brute force” method has been used for restoration of the testing images. The results of different deconvolution algorithms are demonstrated in this paper. This approach could help to improve the precision of astronomic measurements.
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- 2008
15. Very Large Telescope Spectroscopy of Ultra-faint Dwarf Galaxies. I. Boötes I, Leo IV, and Leo V
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Sydney Jenkins, Tenglin Li, Alexander P. Ji, Andrew B. Pace, Sergey E. Koposov, and Burçin Mutlu-Pakdil
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Physics ,Stellar kinematics ,Very Large Telescope ,010308 nuclear & particles physics ,astro-ph.GA ,Metallicity ,Dark matter ,Astronomy ,Local Group ,Astronomy and Astrophysics ,BOOTES ,01 natural sciences ,Space and Planetary Science ,0103 physical sciences ,Binary star ,010303 astronomy & astrophysics ,Dwarf galaxy - Abstract
We perform consistent reductions and measurements for three ultra-faint dwarf galaxies (UFDs):Bo ̈otes I, Leo IV and Leo V. Using the public archival data from the GIRAFFE spectrograph on theVery Large Telescope (VLT), we locate new members and provide refined measurements of physicalparameters for these dwarf galaxies. We identify nine new Leo IV members and four new Leo Vmembers, and perform a comparative analysis of previously discovered members. Additionally, weidentify one new binary star in both Leo IV and Leo V. After removing binary stars, we recalculatethe velocity dispersions of Bo ̈otes I and Leo IV to be 5.1+0.7−0.8and 3.4+1.3−0.9km s−1, respectively; Wedo not resolve the Leo V velocity dispersion. We identify a weak velocity gradient in Leo V thatis∼4×smaller than the previously calculated gradient and that has a corresponding position anglewhich differs from the literature value by∼120 deg. Combining the VLT data with previous literature,we re-analyze the Bo ̈otes I metallicity distribution function and find that a model including infall ofpristine gas while Bo ̈otes I was forming stars best fits the data. Our analysis of Leo IV, Leo V andother UFDs will enhance our understanding of these enigmatic stellar populations and contribute tofuture dark matter studies. This is the first in a series of papers examining thirteen UDFs observedwith VLT/GIRAFFE between 2009 and 2017. Similar analyses of the remaining ten UFDs will bepresented in forthcoming papers
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- 2021
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16. The Ultraviolet Deep Imaging Survey of Galaxies in the Bootes Void. I. Catalog, Color–Magnitude Relations, and Star Formation
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Kanak Saha, Ananta C. Pradhan, and Divya Pandey
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Physics ,Void (astronomy) ,Star formation ,Infrared ,media_common.quotation_subject ,FOS: Physical sciences ,Astronomy and Astrophysics ,BOOTES ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Void galaxy ,Space and Planetary Science ,Sky ,Astrophysics of Galaxies (astro-ph.GA) ,Magnitude (astronomy) ,Astrophysics::Solar and Stellar Astrophysics ,Astrophysics::Galaxy Astrophysics ,media_common - Abstract
We present a deep far and near-ultraviolet (FUV and NUV) wide-field imaging survey of galaxies in the Bootes Void using Ultra-Violet Imaging Telescope onboard {\em AstroSat}. Our data reach $5\sigma$ limiting magnitudes for point sources at 23.0 and 24.0 AB mag in FUV and NUV respectively. We report a total of six star-forming galaxies residing in the Bootes Void alongside the full catalog, and of these, three are newly detected in our FUV observation. Our void galaxy sample spans a range of UV colors $(-0.35\, \leq$ FUV$-$NUV $\leq\, 0.68)$ and absolute magnitudes $(-14.16\, \leq\, \mathrm{M_{NUV}}\, \leq\, -18.65)$. In addition, {\em Sloan Digital Sky Survey} and {\em Two-micron All Sky Survey} archival data are being used to study UV, optical, and infrared color-magnitude relations for our galaxies in the void. We investigate the nature of bi-modal color distribution, morphologies, and star formation of the void galaxies. Most of the galaxies in our sample are fainter and less massive than L$^{\ast}$ galaxies, with M$_\mathrm{r} > -20$. Our analysis reveals a dominant fraction of bluer galaxies over the red ones in the void region probed. The internal and Galactic extinction corrected FUV star formation rates (SFRs) in our void galaxy catalog varies in a large range of $0.05$ to $51.01$ M$_{\odot} yr^{-1}$, with a median $3.96$ M$_{\odot} yr^{-1}$. We find a weak effect of the environment on the SFRs of galaxies. Implications of our findings are discussed., Comment: 19 pages, 16 figures, accepted for publication in ApJ
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- 2021
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17. Nearby groups of galaxies in the Hercules–Bootes constellations
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Olga G. Kashibadze, Valentina E. Karachentseva, and Igor D. Karachentsev
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Physics ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,Stellar mass ,FOS: Physical sciences ,Velocity dispersion ,Astronomy and Astrophysics ,BOOTES ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Radius ,010501 environmental sciences ,Mass ratio ,Astrophysics - Astrophysics of Galaxies ,01 natural sciences ,Galaxy ,Local Void ,Radial velocity ,Astrophysics of Galaxies (astro-ph.GA) ,0103 physical sciences ,Astrophysics::Earth and Planetary Astrophysics ,010303 astronomy & astrophysics ,Instrumentation ,Astrophysics::Galaxy Astrophysics ,Astrophysics - Cosmology and Nongalactic Astrophysics ,0105 earth and related environmental sciences - Abstract
We consider a sample of 412 galaxies with radial velocities $V_{\rm LG} < 2500$ km s$^{-1}$ situated in the sky region of ${\rm RA}=13^h\hspace{-0.4em}.\,0$ ... $19^h\hspace{-0.4em}.\,0$, ${\rm Dec}=+10^{\circ}$ ... $+40^{\circ}$ between the Local Void and the Supergalactic plane. One hundred and eighty-one of them have individual distance estimates. Peculiar velocities of the galaxies as a function of Supergalactic latitude SGB show signs of Virgocentric infall at $SGB < 10^{\circ}$ and motion from the Local Void at $SGB > 60^{\circ}$. A half of the Hercules-Bootes galaxies belong to 17 groups and 29 pairs, with the richest group around NGC5353. A typical group is characterized by the velocity dispersion of $67$ km s$^{-1}$, the harmonic radius of $182$ kpc, the stellar mass of $4.3 \times10^{10} M_{\odot}$ and the virial-to-stellar mass ratio of $32$. The binary galaxies have the mean radial velocity difference of $37$ km s$^{-1}$, the projected separation of $96$ kpc, the mean integral stellar mass of $2.6\times 10^9 M_{\odot}$ and the mean virial-to-stellar mass ratio of about $8$. The total dark-matter-to-stellar mass ratio in the considered sky region amounts to $37$ being almost the same as that in the Local Volume., 11 pages, 5 figures, 4 tables. Accepted to Astrophysical Bulletin
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- 2017
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18. The Spectral Energy Distributions of Active Galactic Nuclei
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Claudio Ricci, Kenneth Duncan, Tonima Tasnim Ananna, Hermine Landt, N. Kamraj, M. Kirk, Mara Salvato, Michael J. I. Brown, Boquien, M., Lusso, E, Gruppioni, C, and Tissera, P.
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Physics ,Active galactic nucleus ,010308 nuclear & particles physics ,astro-ph.GA ,Astrophysics::High Energy Astrophysical Phenomena ,FOS: Physical sciences ,Spectral density ,Astronomy and Astrophysics ,BOOTES ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Redshift ,Photometry (optics) ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,0103 physical sciences ,Astrophysics::Solar and Stellar Astrophysics ,Astrophysics::Earth and Planetary Astrophysics ,Spectral resolution ,Spectroscopy ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics - Abstract
We present spectral energy distributions (SEDs) of 41 active galactic nuclei, derived from multiwavelength photometry and archival spectroscopy. All of the SEDs span at least 0.09 to 30 micron, but in some instances wavelength coverage extends into the X-ray, far-infrared and radio. For some AGNs we have fitted the measured far-infrared photometry with greybody models, while radio flux density measurements have been approximated by power-laws or polynomials. We have been able to fill some of the gaps in the spectral coverage using interpolation or extrapolation of simple models. In addition to the 41 individual AGN SEDs, we have produced 72 Seyfert SEDs by mixing SEDs of the central regions of Seyferts with galaxy SEDs. Relative to the literature, our templates have broader wavelength coverage and/or higher spectral resolution. We have tested the utility of our SEDs by using them to generate photometric redshifts for 0 < z < 6.12 AGNs in the Bootes field (selected with X-ray, IR and optical criteria) and, relative to SEDs from the literature, they produce comparable or better photometric redshifts with reduced flux density residuals., Accepted for publication in MNRAS. 19 pages, 14 figures, 4 tables. The AGN spectral energy distributions, photometry and images are available via https://archive.stsci.edu/hlsp/agnsedatlas
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- 2019
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19. Bo\'otes IV: A New Milky Way Satellite Discovered in the Subaru Hyper Suprime-Cam Survey and Implications for the Missing Satellite Problem
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Hitoshi Murayama, Mikito Tanaka, Masashi Chiba, Nobuo Arimoto, Kohei Hayashi, Robert H. Lupton, Scott G. Carlsten, Daisuke Homma, Satoshi Miyazaki, Shiang-Yu Wang, Sakurako Okamoto, Yutaka Komiyama, Masayuki Tanaka, G. Torrealba, Michael A. Strauss, and Miho N. Ishigaki
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Absolute magnitude ,Physics ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,Stellar population ,010308 nuclear & particles physics ,Milky Way ,Dwarf galaxy problem ,FOS: Physical sciences ,Astronomy and Astrophysics ,BOOTES ,Astrophysics ,01 natural sciences ,Astrophysics - Astrophysics of Galaxies ,Stars ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,Globular cluster ,0103 physical sciences ,Satellite galaxy ,010303 astronomy & astrophysics ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We report on the discovery of a new Milky Way (MW) satellite in Bo\"otes based on data from the on-going Hyper Suprime-Cam (HSC) Subaru Strategic Program (SSP). This satellite, named Bo\"otes IV, is the third ultra-faint dwarf that we have discovered in the HSC-SSP. We have identified a statistically significant (32.3$\sigma$) overdensity of stars having characteristics of a metal-poor, old stellar population. The distance to this stellar system is $D_{\odot}=209^{+20}_{-18}$ kpc with a $V$-band absolute magnitude of $M_V=-4.53^{+0.23}_{-0.21}$ mag. Bo\"otes IV has a half-light radius of $r_h=462^{+98}_{-84}$ pc and an ellipticity of $0.64^{+0.05}_{-0.05}$, which clearly suggests that this is a dwarf satellite galaxy. We also found another overdensity that appears to be a faint globular cluster with $M_V=-0.20^{+0.59}_{-0.83}$ mag and $r_h=5.9^{+1.5}_{-1.3}$ pc located at $D_{\odot}=46^{+4}_{-4}$ kpc. Adopting the recent prediction for the total population of satellites in a MW-sized halo by Newton et al. (2018), which combined the characteristics of the observed satellites by SDSS and DES with the subhalos obtained in $\Lambda$CDM models, we estimate that there should be about two MW satellites at $M_V\le0$ in the $\sim676$ deg$^2$ covered by HSC-SSP, whereas that area includes six satellites. Thus, the observed number of satellites is larger than the theoretical prediction. On the face of it, we have a problem of too many satellites, instead of the well-known missing satellites problem whereby the $\Lambda$CDM theory overpredicts the number of satellites in a MW-sized halo. This may imply that the models need more refinements for the assignment of subhalos to satellites such as considering those found by the current deeper survey. [abridged], Comment: 13 pages, 11 figures, 2 tables, accepted for publication in PASJ
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- 2019
20. Optical multi-color monitoring of the BL Lacertae Object S5 0716+714 with BOOTES-4
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Dingrong Xiong, Chuan-Jun Wang, and Jin-Ming Bai
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Physics ,Brightness ,Flux ,Astronomy and Astrophysics ,BOOTES ,Astrophysics ,Correlation function (astronomy) ,01 natural sciences ,law.invention ,Telescope ,Amplitude ,Space and Planetary Science ,Observatory ,law ,0103 physical sciences ,010303 astronomy & astrophysics ,BL Lac object - Abstract
S5 0716+714 had been monitored from November, 2017 to May, 2018 with the 60 cm autonomous telescope BOOTES-4 (the fourth station of the BOOTES network), which located at the Lijiang Observatory of the Yunnan Observatories, the Chinese Academy of Sciences. The observations include 125 nights. The time span per night is from 0.026 hours to 10.73 hours (average time span 3.94 hours). The time intervals between two adjacent bands are about 2.23 minutes. With the high quality data, we use one-way analysis of variance (ANOVA) and $F$ -test to check the intraday flux variability (IDV) by considering the 62 nights with time span more than 4 hours. The values of duty cycle (DC) are 77%, 83%, 74% for $g$ , $r$ , $i$ bands respectively. The intraday flux variability amplitude distributions are from 2.54% to 35.35% and the mean value is 16.33%. The analysis of z-transformed discrete correlation function (ZDCF) shows that the significant time lags between different wavebands are not found. The scope of characteristic flux variability timescales is from 0.015 day to 0.164 day, and the mean value is 0.066 day. Most of nights show bluer when brighter (BWB) trends while some nights have weak BWB trends or redder-when brighter (RWB) trends in different brightness. The shock-in-jet model and multiple variation components in the jet could explain the IDV and color behaviors.
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- 2019
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21. Daouidi v Bootes Plus SL and the Concept of ‘Disability’ in EU Anti-Discrimination Law
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Delia Ferri
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Anti-discrimination law ,Political science ,Law ,Realm ,Legislation ,BOOTES ,Social model of disability ,Medical model of disability - Abstract
Daouidi v Bootes Plus SL is one the latest decisions in which the CJEU has been directly confronted with the concept of disability in the realm of EU anti-discrimination legislation. In particular, in this judgment, the Court attempted to identify when the dismissal of a worker due to temporary incapacity of an unknown duration may constitute direct discrimination on the grounds of disability. This decision appears to be significant in that, for the first time, the CJEU discusses the meaning of ‘long-term limitation’ for the purpose of Directive 2000/78. Although the Court treads carefully, it attempts to further elucidate and bring new elements to the definition of disability in EU anti-discrimination law. In spite of the fact that the Court is potentially widening the notion of disability, it appears, once again, quite reticent in its approach to the role of social, environmental and attitudinal barriers in disabling an individual, and remains somewhat ‘trapped’ in the medical model of disability. All in all, this analysis endeavors to highlight that the CJEU is struggling to move beyond a rhetorical recognition of the social model of disability and to apply this in practice.
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- 2019
22. LOFAR 150-MHz observations of the Boötes field: catalogue and source counts
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Matt J. Jarvis, J. Sabater, N. J. Jackson, F. de Gasperin, Michael W. Wise, D. Engels, Emanuela Orrú, George K. Miley, Timothy W. Shimwell, E. Retana-Montenegro, R. Morganti, Wendy L. Williams, Marcus Brüggen, M. C. Toribio, Martin J. Hardcastle, T. J. Dijkema, Glenn J. White, Elizabeth K. Mahony, John Conway, Marijke Haverkorn, Leah K. Morabito, Isabella Prandoni, S. S. Sridhar, Philip Best, Jonathan T. L. Zwart, R. J. van Weeren, Chiara Ferrari, Gianfranco Brunetti, George Heald, Anna D. Kapińska, Heino Falcke, C. Tasse, I. van Bemmel, Torsten A. Enßlin, Huub Röttgering, Netherlands Institute for Radio Astronomy (ASTRON), Leiden Observatory [Leiden], Universiteit Leiden [Leiden], University of Edinburgh, Hamburger Sternwarte/Hamburg Observatory, Universität Hamburg (UHH), University of Hertfordshire [Hatfield] (UH), Institute for Astronomy [Edinburgh] (IfA), SKA South Africa, Ska South Africa, Galaxies, Etoiles, Physique, Instrumentation (GEPI), 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)-Centre National de la Recherche Scientifique (CNRS), Jacobs University [Bremen], Joseph Louis LAGRANGE (LAGRANGE), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Radboud university [Nijmegen], University of Oxford [Oxford], Centre d'études européennes et de politique comparée (CEE), Sciences Po (Sciences Po)-Centre National de la Recherche Scientifique (CNRS), Unité de Recherche sur les Maladies Infectieuses Tropicales Emergentes (URMITE), Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes (URMITE), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-IFR48, INSB-INSB-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-IFR48, INSB-INSB-Centre National de la Recherche Scientifique (CNRS), SLAC National Accelerator Laboratory (SLAC), Stanford University, Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Centre d'études européennes et de politique comparée (Sciences Po, CNRS) (CEE), High Energy Astrophys. & Astropart. Phys (API, FNWI), Astronomy, bibliotheque, la., Leiden University, Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University [Cambridge]-Smithsonian Institution, SUPA School of Physics and Astronomy [Edinburgh], University of Hamburg, University of Groningen [Groningen], INAF - Osservatorio Astronomico di Bologna (OABO), Istituto Nazionale di Astrofisica (INAF), Joint Institute for VLBI in Europe (JIVE ERIC), Chalmers University of Technology [Göteborg], Max Planck Institute for Astrophysics, Max-Planck-Gesellschaft, Radboud University [Nijmegen], Observatoire de la Côte d'Azur (OCA), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Jodrell Bank Centre for Astrophysics (JBCA), University of Manchester [Manchester], University of Oxford, University of the Western Cape, International Centre for Radio Astronomy Research (ICRAR), The University of Western Australia (UWA)-Government of Western Australia-Curtin University [Perth], Planning and Transport Research Centre (PATREC)-Planning and Transport Research Centre (PATREC), Institute of Cosmology and Gravitation [Portsmouth] (ICG), University of Portsmouth, Centre of Excellence for All-Sky Astrophysics (CAASTRO), Kapteyn Astronomical Institute [Groningen], The Open University [Milton Keynes] (OU), STFC Rutherford Appleton Laboratory (RAL), Science and Technology Facilities Council (STFC), and University of Cape Town
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active [Galaxies] ,Hubble Deep Field ,DEEP FIELD ,Astronomy ,Astrophysics::High Energy Astrophysical Phenomena ,galaxies: active ,Flux ,Ecliptic pole ,galaxies [Radio continuum] ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Surveys ,X-RAY SURVEY ,01 natural sciences ,[PHYS] Physics [physics] ,surveys ,610-MHZ SURVEY ,0103 physical sciences ,DATA REDUCTION ,Angular resolution ,Source counts ,ECLIPTIC POLE ,Techniques:interferometric ,Radio continuum:galaxies ,010303 astronomy & astrophysics ,ComputingMilieux_MISCELLANEOUS ,radio continuum: galaxies ,[PHYS]Physics [physics] ,Physics ,010308 nuclear & particles physics ,20 CM ,SPECTRUM SOURCES ,Astronomy and Astrophysics ,BOOTES ,LOFAR ,FREQUENCY SKY SURVEY ,1ST SURVEY ,Galaxy ,Galaxies:active ,techniques: interferometric ,Space and Planetary Science ,ComputingMethodologies_DOCUMENTANDTEXTPROCESSING ,interferometric [Techniques] ,[PHYS.ASTR] Physics [physics]/Astrophysics [astro-ph] ,Astrophysics - Instrumentation and Methods for Astrophysics ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,Astrophysics - Cosmology and Nongalactic Astrophysics ,METREWAVE-RADIO-TELESCOPE - Abstract
We present the first wide area (19 deg$^2$), deep ($\approx120-150$ {\mu}Jy beam$^{-1}$), high resolution ($5.6 \times 7.4$ arcsec) LOFAR High Band Antenna image of the Bo\"otes field made at 130-169 MHz. This image is at least an order of magnitude deeper and 3-5 times higher in angular resolution than previously achieved for this field at low frequencies. The observations and data reduction, which includes full direction-dependent calibration, are described here. We present a radio source catalogue containing 6276 sources detected over an area of $19$\,deg$^2$, with a peak flux density threshold of $5\sigma$. As the first thorough test of the facet calibration strategy, introduced by van Weeren et al., we investigate the flux and positional accuracy of the catalogue. We present differential source counts that reach an order of magnitude deeper in flux density than previously achieved at these low frequencies, and show flattening at 150 MHz flux densities below 10 mJy associated with the rise of the low flux density star-forming galaxies and radio-quiet AGN., Comment: 29 pages, 27 figures, accepted for publication in MNRAS
- Published
- 2016
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23. A Decade of GRB Follow-Up by BOOTES in Spain (2003–2013)
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S. Guziy, Rafael Fernández-Muñoz, Ronan Cunniffe, S. Jeong, T. M. Sanguino, Javier Gorosabel, Stanislav Vítek, R. Sanchez-Ramirez, Petr Páta, L. Sabau-Graziati, Antonio de Ugarte Postigo, Ovidio Rabaza, D. Perez-Ramirez, S. Castillo-Carrión, Petr Kubánek, Benito A. de la Morena Carretero, Samantha Oates, A. J. Castro-Tirado, Jan Strobl, René Hudec, Victor Reglero, Martin Jelínek, J. C. Tello, Junta de Andalucía, Ministerio de Economía y Competitividad (España), and Czech Science Foundation
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spectroscopy ,Article Subject ,lcsh:Astronomy ,100418A ,FOS: Physical sciences ,gamma-ray burst ,02 engineering and technology ,01 natural sciences ,lcsh:QB1-991 ,emission ,0103 physical sciences ,0202 electrical engineering, electronic engineering, information engineering ,panchromatic observations ,010303 astronomy & astrophysics ,High Energy Astrophysical Phenomena (astro-ph.HE) ,Physics ,shooter ,energy injection ,Astronomy ,Astronomy and Astrophysics ,BOOTES ,host-galaxy ,Space and Planetary Science ,28 February 1997 ,020201 artificial intelligence & image processing ,Astrophysics - High Energy Astrophysical Phenomena ,afterglow ,Gamma-ray burst - Abstract
This article covers ten years of GRB follow-ups by the Spanish BOOTES stations: 71 follow-ups providing 23 detections. Follow-ups by BOOTES-1B from 2005 to 2008 were given in a previous article and are here reviewed and updated, and additional detection data points are included as the former article merely stated their existence. The all-sky cameras CASSANDRA have not yet detected any GRB optical afterglows, but limits are reported where available., The authors appreciate the auspices of INTA, IHSM-UMA/CSIC, and UMA as well as the financial support by the Junta de Andaluca and the Spanish Ministry of Economy and Competitiveness through the Research Projects P07-TIC-03094, P12-TIC2839, AYA2009-14000-C03-01, AYA 2010-39727-C03-01, and AYA-2015-71718-R. Martin Jelinek was supported by the postdoctoral fellowship of the Czech Academy of Sciences. This study was carried out in the framework of the Unidad Asociada IAA-CSIC at the Group of Planetary Science of ETSI-UPV/EHU. This work was supported by the Ikerbasque Foundation for Science. The Czech CVUT FEL team acknowledges the support by GA CR Grant 13-33324S.
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- 2016
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24. The Chandra Deep Wide-field Survey: A New Chandra Legacy Survey in the Boötes Field. I. X-Ray Point Source Catalog, Number Counts, and Multiwavelength Counterparts
- Author
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Stephen S. Murray, Christine Jones, Alexey Vikhlinin, Anthony H. Gonzalez, Kevin N. Hainline, M. A. DiPompeo, Ryan C. Hickox, Richard G. Bower, Daniel Stern, Kenneth Duncan, Michael J. I. Brown, Eric D. Miller, Alberto Masini, Peter Eisenhardt, Andrew Ptak, James Aird, William R. Forman, David M. Alexander, Chien-Ting J. Chen, Mark Brodwin, Christopher S. Kochanek, David A. Wake, A. Stanford, Ralph P. Kraft, James Mullaney, Buell T. Jannuzi, Christopher M. Carroll, Andy D. Goulding, Roberto J. Assef, Adam D. Myers, Arjun Dey, Suchetana Chatterjee, and Kyoung-Soo Lee
- Subjects
Physics ,X-ray astronomy ,Active galactic nucleus ,COSMIC cancer database ,010504 meteorology & atmospheric sciences ,Point source ,Astrophysics::High Energy Astrophysical Phenomena ,Astronomy and Astrophysics ,BOOTES ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,01 natural sciences ,Redshift ,Space and Planetary Science ,Observatory ,0103 physical sciences ,Catalog Number ,Astrophysics - High Energy Astrophysical Phenomena ,010303 astronomy & astrophysics ,0105 earth and related environmental sciences - Abstract
We present a new, ambitious survey performed with the Chandra X-ray Observatory of the 9.3 deg$^2$ Bo\"otes field of the NOAO Deep Wide-Field Survey. The wide field probes a statistically representative volume of the Universe at high redshift. The Chandra Deep Wide-Field Survey exploits the excellent sensitivity and angular resolution of Chandra over a wide area, combining 281 observations spanning 15 years, for a total exposure time of 3.4 Ms, and detects 6891 X-ray point sources down to limiting fluxes of $4.7\times10^{-16}$, $1.5\times10^{-16}$, and $9\times10^{-16}$ erg cm$^{-2}$ s$^{-1}$, in the $0.5-7$ keV, $0.5-2$ keV, and $2-7$ keV bands, respectively. The robustness and reliability of the detection strategy is validated through extensive, state-of-the-art simulations of the whole field. Accurate number counts, in good agreement with previous X-ray surveys, are derived thanks to the uniquely large number of point sources detected, which resolve $65.0 \pm 12.8\%$ of the cosmic X-ray background between $0.5-2$ keV and $81.0 \pm 11.5\%$ between $2-7$ keV. Exploiting the wealth of multi-wavelength data available on the field, we assign redshifts to $\sim 94\%$ of the X-ray sources, estimate their obscuration and derive absorption-corrected luminosities. We provide an electronic catalog containing all the relevant quantities needed for future investigations., Comment: Accepted for publication in ApJS. The catalogs associated to this paper can be accessed at http://www.dartmouth.edu/~hickox/cdwfs.php
- Published
- 2020
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25. Revised and New Proper Motions for Confirmed and Candidate Milky Way Dwarf Galaxies
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Kim A. Venn and Alan W. McConnachie
- Subjects
Physics ,Proper motion ,010504 meteorology & atmospheric sciences ,Milky Way ,FOS: Physical sciences ,Local Group ,Astronomy and Astrophysics ,BOOTES ,Astrophysics ,Astrophysics - Astrophysics of Galaxies ,01 natural sciences ,Photometry (optics) ,Radial velocity ,Stars ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,0103 physical sciences ,010303 astronomy & astrophysics ,0105 earth and related environmental sciences ,Dwarf galaxy - Abstract
A new derivation of systemic proper motions of Milky Way satellites is presented, and applied to 59 confirmed or candidate dwarf galaxy satellites using Gaia Data Release 2. This constitutes all known Milky Way dwarf galaxies (and likely candidates) as of May 2020 except the Magellanic Clouds, the Canis Major and Hydra 1 stellar overdensities, and the tidally disrupting Bootes III and Sagittarius dwarf galaxies. We derive systemic proper motions for the first time for Indus 1, DES J0225+0304, Cetus 2, Pictor 2 and Leo T, but note that the latter three rely on photometry that is of poorer quality than for the rest of the sample. We cannot resolve a signal for Bootes 4, Cetus 3, Indus 2, Pegasus 3, or Virgo 1. Our method is inspired by the maximum likelihood approach of Pace & Li (2019) and examines simultaneously the spatial, color-magnitude, and proper motion distribution of sources. Systemic proper motions are derived without the need to identify confirmed radial velocity members, although the proper motions of these stars, where available, are incorporated into the analysis through a prior on the model. The associated uncertainties on the systemic proper motions are on average a factor of $\sim 1.4$ smaller than existing literature values. Analysis of the implied membership distribution of the satellites suggests we accurately identify member stars with a contamination rate less than 1 in 20., 30 pages, 8 figures, 8 tables. Accepted for publication in the Astronomical Journal. Updated version consistent with proofs, including revised Tables 4, 6 and A1, and revised Figures 7 and 8
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- 2020
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26. The Dragonfly Wide Field Survey. I. Telescope, Survey Design, and Data Characterization
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Qing Liu, Johnny P. Greco, Steven Janssens, Pieter van Dokkum, Tim B. Miller, Jiaxuan Li, Charlie Conroy, Roberto Abraham, Lamiya Mowla, Shany Danieli, Allison Merritt, Deborah Lokhorst, Colleen Gilhuly, and Jielai Zhang
- Subjects
Ursa Major ,010504 meteorology & atmospheric sciences ,Milky Way ,media_common.quotation_subject ,Population ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,01 natural sciences ,law.invention ,Telescope ,law ,0103 physical sciences ,Surface brightness ,education ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,0105 earth and related environmental sciences ,media_common ,Physics ,education.field_of_study ,Astrophysics::Instrumentation and Methods for Astrophysics ,Local Group ,Astronomy and Astrophysics ,BOOTES ,Astrophysics - Astrophysics of Galaxies ,Space and Planetary Science ,Sky ,Astrophysics of Galaxies (astro-ph.GA) - Abstract
We present a description of the Dragonfly Wide Field Survey (DWFS), a deep photometric survey of a wide area of sky. The DWFS covers 330 $\mathrm{deg}^2$ in the equatorial GAMA fields and the Stripe 82 fields in the SDSS $g$ and $r$ bands. It is carried out with the 48-lens Dragonfly Telephoto Array, a telescope that is optimized for the detection of low surface brightness emission. The main goal of the survey is to study the dwarf galaxy population beyond the Local Group. In this paper, we describe the survey design and show early results. We reach $1\sigma$ depths of $\mu_g\approx 31$ mag arcsec$^{-2}$ on arcminute scales and show that Milky Way satellites such as Sextans, Bootes, and Ursa Major should be detectable out to $D\gtrsim 10$ Mpc. We also provide an overview of the elements and operation of the 48-lens Dragonfly telescope and a detailed description of its data reduction pipeline. The pipeline is fully automated, with individual frames subjected to a rigorous series of quality tests. The sky subtraction is performed in two stages, ensuring that emission features with spatial scales up to $\sim 0.^{\circ}9 \times 0.^{\circ}6$ are preserved. The DWFS provides unparalleled sensitivity to low surface brightness features on arcminute scales., Comment: Accepted for publication in ApJ. This is the first paper in the series. Preliminary results from the survey are shown in figures 5-10
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- 2020
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27. The optical luminosity function of LOFAR radio-selected quasars at 1.4 ≤ z ≤ 5.0 in the NDWFS-Boötes field
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E. Retana-Montenegro and H. J. A. Röttgering
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Physics ,education.field_of_study ,010308 nuclear & particles physics ,Astrophysics::High Energy Astrophysical Phenomena ,Population ,Astrophysics::Instrumentation and Methods for Astrophysics ,Astronomy and Astrophysics ,BOOTES ,Quasar ,Astrophysics::Cosmology and Extragalactic Astrophysics ,LOFAR ,Astrophysics ,Astrophysics - Astrophysics of Galaxies ,01 natural sciences ,Redshift ,Luminosity ,Photometry (optics) ,Space and Planetary Science ,0103 physical sciences ,education ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Luminosity function ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We present an estimate of the optical luminosity function (OLF) of LOFAR radio-selected quasars (RSQs) at $1.4, Comment: 29 pages, 24 figures. Accepted in A&A
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- 2020
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28. THE CHEMICAL EVOLUTION OF THE BOOTES I ULTRA-FAINT DWARF GALAXY
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Anna Frebel, Rosemary F. G. Wyse, Gerard Gilmore, John E. Norris, Gilmore, Gerard [0000-0003-4632-0213], and Apollo - University of Cambridge Repository
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stars: abundances ,Metallicity ,FOS: Physical sciences ,01 natural sciences ,Galactic halo ,0103 physical sciences ,010303 astronomy & astrophysics ,Solar and Stellar Astrophysics (astro-ph.SR) ,Dwarf galaxy ,Physics ,010308 nuclear & particles physics ,Local Group ,Astronomy ,Astronomy and Astrophysics ,BOOTES ,stars: Population II ,galaxies: dwarf ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,early universe ,Galaxy: halo ,Stars ,Astrophysics - Solar and Stellar Astrophysics ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,Career development - Abstract
We present chemical abundance measurements of two metal-poor red giant stars in the ultra-faint dwarf galaxy Bootes I, based on Magellan/MIKE high-resolution spectra. For Boo I-980, with [Fe/H]=-3.1, we present the first elemental abundance measurements while Boo I-127, with [Fe/H]=-2.0, shows abundances in good agreement with previous measurements. Light and iron-peak element abundance ratios in the two Bootes I stars, as well as those of most other Boootes I members, collected from the literature, closely resemble those of regular metal-poor halo stars. Neutron-capture element abundances Sr and Ba are systematically lower than the main halo trend, and also show a significant abundance spread. Overall, this is similar to what has been found for other ultra-faint dwarf galaxies. We apply corrections to the carbon abundances (commensurate with stellar evolutionary status) of the entire sample and find 21% of stars to be carbon-enhanced metal-poor (CEMP) stars, compared to 13% without using the carbon correction. We reassess the metallicity distribution functions (MDF) for the CEMP stars and non-CEMP stars, and confirm earlier claims that CEMP stars might belong to a different, earlier population. Applying a set of abundance criteria to test to what extent Bootes I could be a surviving first galaxy suggests that it is one of the earliest assembled systems that perhaps received gas from accretion from other clouds in the system, or from swallowing a first galaxy or building block type object. This resulted in the two stellar populations observable today., Comment: accepted for publication in ApJ
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- 2018
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29. Bootes III is a disrupting dwarf galaxy associated with the Styx stellar stream
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Jeffrey L. Carlin and David J. Sand
- Subjects
Physics ,Proper motion ,Metallicity ,Milky Way ,Galactic Center ,FOS: Physical sciences ,Astronomy and Astrophysics ,BOOTES ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Astrophysics - Astrophysics of Galaxies ,010305 fluids & plasmas ,Radial velocity ,Space and Planetary Science ,Globular cluster ,Astrophysics of Galaxies (astro-ph.GA) ,0103 physical sciences ,Astrophysics::Solar and Stellar Astrophysics ,Astrophysics::Earth and Planetary Astrophysics ,10. No inequality ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Dwarf galaxy - Abstract
We present proper motion measurements of Bo\"{o}tes III, an enigmatic stellar satellite of the Milky Way, utilizing data from the second data release of the Gaia mission. By selecting 15 radial velocity confirmed members of Bo\"{o}tes III, along with a likely RR Lyrae member in the vicinity, we measure an error weighted mean proper motion of $(\mu_{\alpha} \cos{\delta}, \mu_\delta) = (-1.14, -0.98)\pm(0.18, 0.20)$ mas/yr. We select and present further stars that may be Bo\"{o}tes III members based on their combined proper motion and position in the color magnitude diagram. We caution against assigning membership to stars that are not confirmed spectroscopically, as we demonstrate that there are contaminating stars from the disrupting globular cluster NGC 5466 in the vicinity of the main body of Bo\"{o}tes III, but we note that our results are consistent with previous Bo\"{o}tes III proper motion estimates that did not include spectroscopic members. Based on the measured proper motion and other known properties of Bo\"{o}tes III, we derive its Galactocentric velocity and compute its orbit given canonical Milky Way potentials with halo masses of both 0.8$\times$10$^{12}$ M$_{\odot}$ and 1.6$\times$10$^{12}$ M$_{\odot}$. These orbits robustly show that Bo\"{o}tes III passed within $\sim$12 kpc of the Galactic center on an eccentric orbit roughly 140 Myr ago. Additionally, the proper motion of Bo\"{o}tes III is in excellent agreement with predictions for the retrograde motion of the coincident Styx stellar stream. Given this, along with the small pericenter and metallicity spread of Bo\"{o}tes III itself, we suggest that it is a disrupting dwarf galaxy giving rise to the Styx stellar stream., Comment: Minor changes to match version accepted to the Astrophysical Journal, including a new Figure 5 placing BooIII in context with other MW dwarfs. Overall conclusions are unchanged
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- 2018
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30. Search for gamma-ray emission from the nearby dwarf spheroidal galaxies with 9 years of Fermi-LAT data
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Xiang Li, Shang Li, Yi-Zhong Fan, Qiang Yuan, Zhao-Qiang Shen, Lei Feng, Yun-Feng Liang, Jin Chang, Neng-Hui Liao, Kai-Kai Duan, and Zi-Qing Xia
- Subjects
Physics ,High Energy Astrophysical Phenomena (astro-ph.HE) ,Annihilation ,010308 nuclear & particles physics ,Milky Way ,Astrophysics::High Energy Astrophysical Phenomena ,Dark matter ,Gamma ray ,Center (category theory) ,FOS: Physical sciences ,BOOTES ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Galaxy ,High Energy Physics - Phenomenology ,High Energy Physics - Phenomenology (hep-ph) ,0103 physical sciences ,Astrophysics - High Energy Astrophysical Phenomena ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Fermi Gamma-ray Space Telescope - Abstract
In this work, we search for $\gamma$-ray emission from the directions of some nearby Milky Way dwarf spheroidal galaxies (dSphs) and candidates with the publicly-available Pass 8 data of Fermi-LAT. Our sample includes 12 sources with the distances $ 4\sigma$) $\gamma$-ray signal., Comment: 7 pages, 4 figures, accepted for publication in PRD
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- 2018
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31. ХИМИЧЕСКАЯ ЭВОЛЮЦИЯ КАРЛИКОВОЙ ГАЛАКТИКИ УЛЬТРАНИЗКОЙ СВЕТИМОСТИ BOÖTES I
- Author
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Lyudmila Mashonkina, Yu. V. Pakhomov, Pascale Jablonka, and Tatyana Sitnova
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Chemical evolution ,Physics ,Astronomy ,BOOTES ,Dwarf galaxy - Published
- 2018
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32. LOFAR-Boötes: properties of high- and low-excitation radio galaxies at $0.5 < z < 2.0$
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G. Calistro Rivera, Elizabeth K. Mahony, Martin J. Hardcastle, Kenneth Duncan, Huub Röttgering, Matt J. Jarvis, Daniel J. Smith, Isabella Prandoni, George K. Miley, F. de Gasperin, Leah K. Morabito, Wendy L. Williams, D. Nisbet, Philip Best, Glenn J. White, Cyril Tasse, Galaxies, Etoiles, Physique, Instrumentation ( GEPI ), Institut national des sciences de l'Univers ( INSU - CNRS ) -Observatoire de Paris-Université Paris Diderot - Paris 7 ( UPD7 ) -Centre National de la Recherche Scientifique ( CNRS ), Galaxies, Etoiles, Physique, Instrumentation (GEPI), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Radio galaxy ,Astrophysics::High Energy Astrophysical Phenomena ,[ PHYS.ASTR ] Physics [physics]/Astrophysics [astro-ph] ,galaxies: active ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,0103 physical sciences ,010303 astronomy & astrophysics ,License ,evolution [galaxies] ,Astrophysics::Galaxy Astrophysics ,Physics ,radio continuum: galaxies ,010308 nuclear & particles physics ,Astronomy ,Astronomy and Astrophysics ,BOOTES ,LOFAR ,Creative commons ,Astrophysics - Astrophysics of Galaxies ,galaxies [radio continuum] ,Space and Planetary Science ,active [galaxies] ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,galaxies: evolution ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
This paper presents a study of the redshift evolution of radio-loud active galactic nuclei (AGN) as a function of the properties of their galaxy hosts in the Bo\"otes field. To achieve this we match low-frequency radio sources from deep $150$-MHz LOFAR observations to an $I$-band-selected catalogue of galaxies, for which we have derived photometric redshifts, stellar masses and rest-frame colours. We present spectral energy distribution (SED) fitting to determine the mid-infrared AGN contribution for the radio sources and use this information to classify them as High- versus Low-Excitation Radio Galaxies (HERGs and LERGs) or Star-Forming galaxies. Based on these classifications we construct luminosity functions for the separate redshift ranges going out to $z = 2$. From the matched radio-optical catalogues, we select a sub-sample of $624$ high power ($P_{150\mathrm{\,MHz}}>10^{25}$ W Hz$^{-1}$) radio sources between $0.5 \leq z < 2$. For this sample, we study the fraction of galaxies hosting HERGs and LERGs as a function of stellar mass and host galaxy colour. The fraction of HERGs increases with redshift, as does the fraction of sources in galaxies with lower stellar masses. We find that the fraction of galaxies that host LERGs is a strong function of stellar mass as it is in the local Universe. This, combined with the strong negative evolution of the LERG luminosity functions over this redshift range, is consistent with LERGs being fuelled by hot gas in quiescent galaxies., Comment: 25 pages, 21 figures, accepted for publication in MNRAS
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- 2018
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33. Photometric redshifts for the next generation of deep radio continuum surveys - I: Template fitting
- Author
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Lo Faro, B., Buat, Veronique, Roehlly, Y., Alvarez-Marquez, J., Burgarella, Denis, Silva, L., Efstathiou, A., Duncan, Kenneth, Brown, Michael, Williams, Wendy, Best, Philip, Jarvis, Matt, Małek, Katarzyna, Oliver, S., Röttgering, Huub, Smith, Daniel, Laboratoire d'Astrophysique de Marseille (LAM), and 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)
- Subjects
Active galactic nucleus ,Astrophysics::High Energy Astrophysical Phenomena ,Population ,Continuum (design consultancy) ,FOS: Physical sciences ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Luminosity ,0103 physical sciences ,education ,010303 astronomy & astrophysics ,ComputingMilieux_MISCELLANEOUS ,Astrophysics::Galaxy Astrophysics ,Photometric redshift ,QB ,Physics ,education.field_of_study ,[SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph] ,010308 nuclear & particles physics ,Astronomy and Astrophysics ,BOOTES ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Redshift ,galaxies [radio continuum] ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,active [galaxies] ,distances and redshifts [galaxies] ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] - Abstract
We present a study of photometric redshift performance for galaxies and active galactic nuclei detected in deep radio continuum surveys. Using two multi-wavelength datasets, over the NOAO Deep Wide Field Survey Bo\"otes and COSMOS fields, we assess photometric redshift (photo-z) performance for a sample of $\sim 4,500$ radio continuum sources with spectroscopic redshifts relative to those of $\sim 63,000$ non radio-detected sources in the same fields. We investigate the performance of three photometric redshift template sets as a function of redshift, radio luminosity and infrared/X-ray properties. We find that no single template library is able to provide the best performance across all subsets of the radio detected population, with variation in the optimum template set both between subsets and between fields. Through a hierarchical Bayesian combination of the photo-z estimates from all three template sets, we are able to produce a consensus photo-z estimate which equals or improves upon the performance of any individual template set., Comment: 20 pages, 17 figures. Accepted for publication in MNRAS
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- 2017
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34. Bo\'otes-HiZELS: an optical to near-infrared survey of emission-line galaxies at $\bf z=0.4-4.7$
- Author
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Ian Smail, Philip Best, David Sobral, Huub Röttgering, Fuyan Bian, Xiaohui Fan, Behnam Darvish, and Jorryt Matthee
- Subjects
Physics ,010308 nuclear & particles physics ,Near-infrared spectroscopy ,Astronomy ,Astronomy and Astrophysics ,BOOTES ,Astrophysics ,01 natural sciences ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,mass function ,Space and Planetary Science ,Observatory ,active [galaxies] ,0103 physical sciences ,Emission spectrum ,star formation [galaxies] ,Astronomy observatory ,010303 astronomy & astrophysics ,evolution [galaxies] ,high-redshift [galaxies] ,luminosity function [galaxies] ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We present a sample of $\sim 1000$ emission line galaxies at $z=0.4-4.7$ from the $\sim0.7$deg$^2$ High-$z$ Emission Line Survey (HiZELS) in the Bo\"otes field identified with a suite of six narrow-band filters at $\approx 0.4-2.1$ $\mu$m. These galaxies have been selected on their Ly$\alpha$ (73), {\sc [Oii]} (285), H$\beta$/{\sc [Oiii]} (387) or H$\alpha$ (362) emission-line, and have been classified with optical to near-infrared colours. A subsample of 98 sources have reliable redshifts from multiple narrow-band (e.g. [O{\sc ii}]-H$\alpha$) detections and/or spectroscopy. In this survey paper, we present the observations, selection and catalogs of emitters. We measure number densities of Ly$\alpha$, [O{\sc ii}], H$\beta$/{\sc [Oiii]} and H$\alpha$ and confirm strong luminosity evolution in star-forming galaxies from $z\sim0.4$ to $\sim 5$, in agreement with previous results. To demonstrate the usefulness of dual-line emitters, we use the sample of dual [O{\sc ii}]-H$\alpha$ emitters to measure the observed [O{\sc ii}]/H$\alpha$ ratio at $z=1.47$. The observed [O{\sc ii}]/H$\alpha$ ratio increases significantly from 0.40$\pm0.01$ at $z=0.1$ to 0.52$\pm0.05$ at $z=1.47$, which we attribute to either decreasing dust attenuation with redshift, or due to a bias in the (typically) fiber-measurements in the local Universe which only measure the central kpc regions. At the bright end, we find that both the H$\alpha$ and Ly$\alpha$ number densities at $z\approx2.2$ deviate significantly from a Schechter form, following a power-law. We show that this is driven entirely by an increasing X-ray/AGN fraction with line-luminosity, which reaches $\approx 100$ \% at line-luminosities $L\gtrsim3\times10^{44}$ erg s$^{-1}$., Comment: Accepted for publication in MNRAS. Main text 16 pages, 7 Figures. Catalogues of line-emitters available
- Published
- 2017
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35. Investigating the unification of LOFAR-detected powerful AGN in the Boötes field
- Author
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Gianfranco Brunetti, Isabella Prandoni, George K. Miley, Wendy L. Williams, Matt J. Jarvis, Martin J. Hardcastle, A. Saxena, Jeremy J. Harwood, D. Engels, Kenneth Duncan, Timothy W. Shimwell, Huub Röttgering, Cyril Tasse, Leah K. Morabito, Philip Best, Marcus Brüggen, Krzysztof T. Chyzy, Aleksandar Shulevski, Peter Barthel, Elizabeth K. Mahony, Galaxies, Etoiles, Physique, Instrumentation ( GEPI ), Institut national des sciences de l'Univers ( INSU - CNRS ) -Observatoire de Paris-Université Paris Diderot - Paris 7 ( UPD7 ) -Centre National de la Recherche Scientifique ( CNRS ), Galaxies, Etoiles, Physique, Instrumentation (GEPI), 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)-Centre National de la Recherche Scientifique (CNRS), PSL Research University (PSL)-PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), and Astronomy
- Subjects
ACTIVE GALACTIC NUCLEI ,Active galactic nucleus ,UNIFIED SCHEMES ,Radio galaxy ,Astrophysics::High Energy Astrophysical Phenomena ,[ PHYS.ASTR ] Physics [physics]/Astrophysics [astro-ph] ,galaxies: active ,jets [galaxies] ,SPECTRAL ENERGY-DISTRIBUTIONS ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,7C REDSHIFT SURVEY ,01 natural sciences ,0103 physical sciences ,BLACK-HOLES ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Physics ,radio continuum: galaxies ,010308 nuclear & particles physics ,RADIO-SOURCE SURVEY ,Astronomy and Astrophysics ,Quasar ,BOOTES ,LOFAR ,galaxies: jets ,Astrophysics - Astrophysics of Galaxies ,Redshift ,Galaxy ,galaxies [radio continuum] ,GALAXIES ,UMINOSITY FUNCTION ,Space and Planetary Science ,active [galaxies] ,Radio frequency ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,COMPLETE QUASAR SAMPLE ,Astrophysics - Cosmology and Nongalactic Astrophysics ,OPTICAL SPECTROSCOPY - Abstract
Low radio frequency surveys are important for testing unified models of radio-loud quasars and radio galaxies. Intrinsically similar sources that are randomly oriented on the sky will have different projected linear sizes. Measuring the projected linear sizes of these sources provides an indication of their orientation. Steep-spectrum isotropic radio emission allows for orientation-free sample selection at low radio frequencies. We use a new radio survey of the Bo\"otes field at 150 MHz made with the Low Frequency Array (LOFAR) to select a sample of radio sources. We identify 44 radio galaxies and 16 quasars with powers $P>10^{25.5}$ W Hz$^{-1}$ at 150 MHz using cross-matched multi-wavelength information from the AGN and Galaxy Evolution Survey (AGES), which provides spectroscopic redshifts. We find that LOFAR-detected radio sources with steep spectra have projected linear sizes that are on average 4.4$\pm$1.4 larger than those with flat spectra. The projected linear sizes of radio galaxies are on average 3.1$\pm$1.0 larger than those of quasars (2.0$\pm$0.3 after correcting for redshift evolution). Combining these results with three previous surveys, we find that the projected linear sizes of radio galaxies and quasars depend on redshift but not on power. The projected linear size ratio does not correlate with either parameter. The LOFAR data is consistent within the uncertainties with theoretical predictions of the correlation between the quasar fraction and linear size ratio, based on an orientation-based unification scheme., Comment: 14 pages, accepted for publication in MNRAS
- Published
- 2017
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36. The phase-space structure of nearby dark matter as constrained by the SDSS
- Author
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Will J. Percival, Jens Jasche, Benjamin D. Wandelt, Guilhem Lavaux, Florent Leclercq, 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), Institut Lagrange de Paris, Sorbonne Universités, Sorbonne Université (SU), Institut d'Astrophysique de Paris ( IAP ), and Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS )
- Subjects
Void (astronomy) ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,[ PHYS.ASTR ] Physics [physics]/Astrophysics [astro-ph] ,media_common.quotation_subject ,Dark matter ,FOS: Physical sciences ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,0202 Atomic, Molecular, Nuclear, Particle And Plasma Physics ,0103 physical sciences ,Coma Cluster ,010303 astronomy & astrophysics ,media_common ,Physics ,COSMIC cancer database ,010308 nuclear & particles physics ,Astronomy and Astrophysics ,BOOTES ,Nuclear & Particles Physics ,Galaxy ,0201 Astronomical And Space Sciences ,Sky ,Phase space ,astro-ph.CO ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
Previous studies using numerical simulations have demonstrated that the shape of the cosmic web can be described by studying the Lagrangian displacement field. We extend these analyses, showing that it is now possible to perform a Lagrangian description of cosmic structure in the nearby Universe based on large-scale structure observations. Building upon recent Bayesian large-scale inference of initial conditions, we present a cosmographic analysis of the dark matter distribution and its evolution, referred to as the dark matter phase-space sheet, in the nearby universe as probed by the Sloan Digital Sky Survey main galaxy sample. We consider its stretchings and foldings using a tetrahedral tessellation of the Lagrangian lattice. The method provides extremely accurate estimates of nearby density and velocity fields, even in regions of low galaxy density. It also measures the number of matter streams, and the deformation and parity reversals of fluid elements, which were previously thought inaccessible using observations. We illustrate the approach by showing the phase-space structure of known objects of the nearby Universe such as the Sloan Great Wall, the Coma cluster and the Bo\"otes void. We dissect cosmic structures into four distinct components (voids, sheets, filaments, and clusters), using the Lagrangian classifiers DIVA, ORIGAMI, and a new scheme which we introduce and call LICH. Because these classifiers use information other than the sheer local density, identified structures explicitly carry physical information about their formation history. Accessing the phase-space structure of dark matter in galaxy surveys opens the way for new confrontations of observational data and theoretical models. We have made our data products publicly available., Comment: 24 pages, 11 figures. Matches JCAP published version. Public data available from the first author's website (currently http://icg.port.ac.uk/~leclercq/data.php)
- Published
- 2017
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37. Motions of Galaxies in the Bootes Strip
- Author
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O. G. Nasonova, V. E. Karachentseva, and Igor D. Karachentsev
- Subjects
Protein filament ,Physics ,Stellar mass ,Dark matter ,Astronomy and Astrophysics ,Virial mass ,BOOTES ,Astrophysics ,Virgo Cluster ,Galaxy ,Local Void - Abstract
We examine the structure and kinematics of the diffuse filament of galaxies lying between the Local Void and the Virgo cluster. For this we use a sample of 361 galaxies with radial velocities V LG 17h . A majority (56%) of the galaxies in the Bootes strip belong to 13 groups and 11 pairs, of which the group around NGC 5846 is the most prominent. The groups in the Bootes strip are at distances of 17-29 Mpc from us, i.e., further than the Virgo cluster. The filament of galaxies in Bootes has a sum stellar mass of 2.7°1012 M ⊙ and a total virial mass of 9.07°1013 M ⊙ with an average density of dark matter of Ω m = 0.09 , or a factor of 3 lower than the global cosmic average.
- Published
- 2014
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38. LOFAR and Radio-Loud AGN
- Author
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Huub Röttgering, Wendy L. Williams, and Reinout J. van Weeren
- Subjects
Physics ,Radio galaxy ,Electromagnetic spectrum ,Astrophysics::High Energy Astrophysical Phenomena ,media_common.quotation_subject ,Astrophysics::Instrumentation and Methods for Astrophysics ,Astronomy ,Astronomy and Astrophysics ,BOOTES ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,LOFAR ,Galaxy ,Radio telescope ,Space and Planetary Science ,Sky ,Astrophysics::Galaxy Astrophysics ,media_common - Abstract
At very low frequencies, the new pan-European radio telescope, LOFAR, is opening the last unexplored window of the electromagnetic spectrum for astrophysical studies. Operating at frequencies from 15 to 240 MHz, its superb sensitivity, high angular resolution, large field of view and flexible spectroscopic capabilities represent a dramatic improvement over previous facilities at these wavelengths. LOFAR will carry out a broad range of fundamental astrophysical studies in a number of key science topics including the formation and evolution of clusters, galaxies and black holes. In this contribution we describe some of the capabilities of LOFAR and present some recent results from the ongoing imaging efforts. We also discuss the impact of LOFAR on our studies of radio-loud AGN. Our recent study of the evolution of radio-loud AGN as a function of host stellar mass shows a clear increase in the fraction of lower mass galaxies which host radio-loud AGN at 1 < z < 2 while the fraction for higher mass galaxies remains the same. This shows that the upturn in the radio luminosity function is driven by increasing AGN activity among low mass galaxies at higher redshifts. New LOFAR observations will allow us to build statistically large samples at high redshifts to constrain this evolution for the different accretion modes of AGN.
- Published
- 2014
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39. Erratum: 'Peculiar Motions of Galaxy Clusters in the Regions of the Corona Borealis, Bootes, Z 5029/A 1424, A1190, A1750/A 1809 Superclusters of Galaxies'
- Author
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F. G. Kopylova and Alexander I. Kopylov
- Subjects
Physics ,010308 nuclear & particles physics ,Astronomy ,Astronomy and Astrophysics ,BOOTES ,Astrophysics ,01 natural sciences ,Galaxy ,Radial velocity ,Galaxy groups and clusters ,Supercluster ,Galaxy group ,0103 physical sciences ,Peculiar velocity ,010303 astronomy & astrophysics ,Instrumentation ,Galaxy cluster - Abstract
We present results of the study of peculiar motions of 57 clusters and groups of galaxies in the regions of the Corona Borealis (CrB), Bootes (Boo), Z5029/A1424, A1190, A1750/A1809 superclusters of galaxies and the galaxy clusters located beyond massive structures (0.05 < z < 0.10). Using the SDSS (Data Release 8) data, a sample of early-type galaxies was compiled in the systems under study, their fundamental planes were built, and relative distances and peculiar velocities were determined. Within the galaxy superclusters, significant peculiar motions along the line of sight are observed with rms deviations of 652 ± 50 kms−1—in CrB, 757 ± 70 kms−1—in Boo. In the most massive A2065 cluster in the CrB supercluster, no peculiar velocity was found. Peculiar motions of the other galaxy clusters can be caused by their gravitational interaction both with A2065 and with the A2142 supercluster. It has been found that there are two superclusters projected onto each other in the region of the Bootes supercluster with a radial velocity difference of about 4000 kms−1. In the Z 5029/A1424 supercluster near the rich Z5029 cluster, the most considerable peculiar motions with a rms deviations of 1366 ± 170 kms−1 are observed. The rms deviations of peculiar velocities of 20 clusters that do not belong to large-scale structures is equal to 0 ± 20 kms−1. The whole sample of the clusters under study has the mean peculiar velocity equal to 83 ± 130 kms−1 relative to the cosmic microwave background.
- Published
- 2018
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40. Metal Abundances and Star Formation Rates of Emission-line Galaxies in and around the Boötes Void
- Author
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John J. Salzer, Alec S. Hirschauer, Joanna M. Taylor, and Gary Wegner
- Subjects
Physics ,Void (astronomy) ,010504 meteorology & atmospheric sciences ,Stellar mass ,Star formation ,Metallicity ,FOS: Physical sciences ,Astronomy and Astrophysics ,BOOTES ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Astrophysics - Astrophysics of Galaxies ,01 natural sciences ,Galaxy ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,0103 physical sciences ,Local environment ,Emission spectrum ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,0105 earth and related environmental sciences - Abstract
We explore the possible dependencies of galaxy metal abundance and star-formation rate (SFR) on local environment, focusing on the volume of space in and around the Bootes Void. Our sample of star-forming galaxies comes from the second catalog of the H-alpha-selected KPNO International Spectroscopic Survey (KISS) which overlaps the void. This sample represents a statistically complete, line-flux-limited ensemble of 820 star-forming galaxies, all of which possess metallicity and SFR estimates. We carry out two distinct analyses of the KISS galaxies: one which probes the properties of the entire sample as a function of local density, and a second which details the properties of 33 KISS star-forming galaxies located within the Bootes Void. In both cases we find no evidence that either the metallicity of the KISS galaxies or their SFRs depend on the environments within which the galaxies are located. Our global analysis does show weak trends for decreasing stellar mass, decreasing metallicity, and decreasing SFRs with decreasing local densities. However, we argue that the metallicity and SFR trends are artifacts of the stellar mass - local density trend. In particular, the change in metallicity with density is precisely what one would predict from the mass-metallicity relation given the observed drop in stellar mass with decreasing metallicity. Likewise, the SFR trend with density disappears when one instead considers the mass-normalized specific SFR. The KISS galaxies dwelling in the Bootes Void are found to have nearly identical metallicity and SFR properties to a matched comparison sample, despite the fact that the former are located in density environments that are, on average, more than 16 times lower., 20 pages, 13 figures; accepted for publication in the ApJ
- Published
- 2019
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- View/download PDF
41. GRBS Followed-up by the bootes network
- Author
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A. de Ugarte Postigo, P. C. M. Yock, Ian A. Bond, T. de J. Mateo Sanguino, O. Rabaza-Castillo, S. Guziy, Rafael Fernández-Muñoz, G. W. Christie, Stanislav Vítek, Chenzhou Cui, L. Sabau-Graziati, Yi-Zhong Fan, O. Lara-Gil, S. Castillo-Carrión, I. Kheyfets, William H. Allen, J. C. Tello, A. J. Castro-Tirado, R. Sanchez-Ramirez, D. Pérez-Ramírez, Petr Kubánek, J. Gorosabel, B. A. de la Morena Carretero, Il Han Park, Martin Jelínek, René Hudec, J. A. Díaz Andreu, J. M. Castro Cerón, Ronan Cunniffe, and C. Perez del Pulgar
- Subjects
Physics ,Space and Planetary Science ,Observatory ,Astrophysics::High Energy Astrophysical Phenomena ,General Engineering ,Astronomy ,Astronomy and Astrophysics ,BOOTES ,Astrophysics ,Gamma-ray burst - Abstract
The Burst Observer and Optical Transient Exploring System (BOOTES), is a global robotic observatory network, which started in 1998 with Spanish leadership devoted to study optical emissions from gamma ray bursts (GRBs) that occur in the Universe. We present shot history and current status of BOOTES network. The Network philosophy, science and some details of 117 GRBs followed-up are discussed.
- Published
- 2013
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42. Status of the BOOTES-IR Project at OSN for GRB near-IR follow-up
- Author
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B. Moliné, Martin Jelínek, F. García-Segura, A. J. Castro-Tirado, Ronan Cunniffe, and J. Gorosabel
- Subjects
Optical camera ,Physics ,Telescope ,Space and Planetary Science ,Observatory ,law ,General Engineering ,Astronomy ,Astronomy and Astrophysics ,BOOTES ,Gamma-ray burst ,Afterglow ,law.invention - Abstract
Bootes-IR () is a robotic observatory based around a 60 cm alt-az telescope (dubbed T60) that can slew rapidly while carrying heavy instrumentation at the Nasmyth foci. Initially commissioned with an optical camera, with which the optical afterglow to GRB 060707 (http://gcn.gsfc.nasa.gov/gcn3/5290.gcn3) was discovered, we have concentrated our efforts on the near-IR (0.8–2.5 μ m) camera (BIRCAM) for which the telescope was specifically designed. The telescope is installed at the Observatorio de Sierra Nevada near Granada in Spain, at an altitude of 3000 m and in an area of very low humidity. The telescope, dome, camera and liquid nitrogen generation and refilling systems have all been recently brought back into operation, and routine observations are expected to begin within the next few months.
- Published
- 2013
- Full Text
- View/download PDF
43. The Diversity of Diffuse Ly$\alpha$ Nebulae around Star-Forming Galaxies at High Redshift
- Author
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Moire K. M. Prescott, Sungryong Hong, Kyoung-Soo Lee, Buell T. Jannuzi, Naveen A. Reddy, Rui Xue, Anthony H. Gonzalez, Hanae Inami, and Arjun Dey
- Subjects
Physics ,Photon ,010308 nuclear & particles physics ,Star formation ,Astronomy and Astrophysics ,BOOTES ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Astrophysics - Astrophysics of Galaxies ,Redshift ,Galaxy ,Gravitation ,Space and Planetary Science ,0103 physical sciences ,Halo ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics - Abstract
We report the detection of diffuse Ly$\alpha$ emission, or Ly$\alpha$ halos (LAHs), around star-forming galaxies at $z\approx3.78$ and $2.66$ in the NOAO Deep Wide-Field Survey Bo\"otes field. Our samples consist of a total of $\sim$1400 galaxies, within two separate regions containing spectroscopically confirmed galaxy overdensities. They provide a unique opportunity to investigate how the LAH characteristics vary with host galaxy large-scale environment and physical properties. We stack Ly$\alpha$ images of different samples defined by these properties and measure their median LAH sizes by decomposing the stacked Ly$\alpha$ radial profile into a compact galaxy-like and an extended halo-like component. We find that the exponential scale-length of LAHs depends on UV continuum and Ly$\alpha$ luminosities, but not on Ly$\alpha$ equivalent widths or galaxy overdensity parameters. The full samples, which are dominated by low UV-continuum luminosity Ly$\alpha$ emitters ($M_{\rm UV} \gtrsim -21$), exhibit LAH sizes of 5$\,-\,6\,$kpc. However, the most UV- or Ly$\alpha$-luminous galaxies have more extended halos with scale-lengths of 7$\,-\,9\,$kpc. The stacked Ly$\alpha$ radial profiles decline more steeply than recent theoretical predictions that include the contributions from gravitational cooling of infalling gas and from low-level star formation in satellites. On the other hand, the LAH extent matches what one would expect for photons produced in the galaxy and then resonantly scattered by gas in an outflowing envelope. The observed trends of LAH sizes with host galaxy properties suggest that the physical conditions of the circumgalactic medium (covering fraction, HI column density, and outflow velocity) change with halo mass and/or star-formation rates., Comment: published in ApJ, minor proof corrections applied
- Published
- 2016
44. Deep Westerbork 1.4 GH[CLC]z[/CLC] Imaging of the Bootes Field
- Author
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Raffaella Morganti, Rene C. Vermeulen, Huub Röttgering, W. H. de Vries, R. Rengelink, W. van Breugel, and Matt J. Jarvis
- Subjects
Physics ,Field (physics) ,Hubble Deep Field ,Radio galaxy ,Astrophysics::High Energy Astrophysical Phenomena ,Astronomy and Astrophysics ,BOOTES ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Redshift ,Square degree ,Radio telescope ,Space and Planetary Science ,Astrophysics::Galaxy Astrophysics ,Luminosity function - Abstract
We present the results from our deep (16x12 hour) Westerbork Synthesis Radio Telescope (WSRT) observations of the approximately 7 square degree Bootes Deep Field, centered at 14h32m05.75s, 34d16'47.5" (J2000). Our survey consists of 42 discrete pointings, with enough overlap to ensure a uniform sensitivity across the entire field, with a limiting sensitivity of 28 microJy (1 sigma rms). The catalog contains 3172 distinct sources, of which 316 are resolved by the 13"x27" beam. The Bootes field is part of the optical/near-infrared imaging and spectroscopy survey effort conducted at various institutions. The combination of these data sets, and the deep nature of the radio observations will allow unique studies of a large range of topics including the redshift evolution of the luminosity function of radio sources, the K-z relation and the clustering environment of radio galaxies, the radio / far-infrared correlation for distant starbursts, and the nature of obscured radio loud AGN.
- Published
- 2016
45. Extended stellar substructure surrounding the Bo\'otes I dwarf spheroidal galaxy
- Author
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T. A. Roderick, G. S. Da Costa, Helmut Jerjen, and Alasdair Mackey
- Subjects
Physics ,I band ,010308 nuclear & particles physics ,Astrophysics::Instrumentation and Methods for Astrophysics ,Velocity dispersion ,Astronomy ,Astronomy and Astrophysics ,BOOTES ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Astrophysics - Astrophysics of Galaxies ,Dwarf spheroidal galaxy ,Photometry (optics) ,Stars ,Space and Planetary Science ,0103 physical sciences ,Dark energy ,Substructure ,Astrophysics::Solar and Stellar Astrophysics ,Astrophysics::Earth and Planetary Astrophysics ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics - Abstract
We present deep stellar photometry of the Bo\"otes I dwarf spheroidal galaxy in g and i band filters, taken with the Dark Energy Camera at Cerro Tololo in Chile. Our analysis reveals a large, extended region of stellar substructure surrounding the dwarf, as well as a distinct over-density encroaching on its tidal radius. A radial profile of the Bo\"otes I stellar distribution shows a break radius indicating the presence of extra-tidal stars. These observations strongly suggest that Bo\"otes I is experiencing tidal disruption, although not as extreme as that exhibited by the Hercules dwarf spheroidal. Combined with revised velocity dispersion measurements from the literature, we see evidence suggesting the need to review previous theoretical models of the Bo\"otes I dwarf spheroidal galaxy., Comment: 13 pages, 13 figures, accepted for publication in MNRAS
- Published
- 2016
46. Dusty Quasars at High Redshifts
- Author
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Daniel W. Weedman and Lusine A. Sargsyan
- Subjects
Astrophysics::High Energy Astrophysical Phenomena ,Population ,FOS: Physical sciences ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Luminosity ,Photometry (optics) ,0103 physical sciences ,Source counts ,education ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Physics ,Luminous infrared galaxy ,education.field_of_study ,010308 nuclear & particles physics ,Astrophysics::Instrumentation and Methods for Astrophysics ,Astronomy and Astrophysics ,Quasar ,BOOTES ,Astrophysics - Astrophysics of Galaxies ,Redshift ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,Astrophysics::Earth and Planetary Astrophysics - Abstract
A population of quasars at z ~ 2 is determined based on dust luminosities vLv(7.8 um) that includes unobscured, partially obscured, and obscured quasars. Quasars are classified by the ratio vLv(0.25 um)/vLv(7.8 um) = UV/IR, assumed to measure obscuration of UV luminosity by the dust which produces IR luminosity. Quasar counts at rest frame 7.8 um are determined for quasars in the Bootes field of the NOAO Deep Wide Field Survey using 24 um sources with optical redshifts from the AGN and Galaxy Evolution Survey (AGES) or infrared redshifts from the Spitzer Infrared Spectrograph. Spectral energy distributions are extended to far infrared wavelengths using observations from the Herschel Space Observatory Spectral and Photometric Imaging Receiver (SPIRE), and new SPIRE photometry is presented for 77 high redshift quasars from the Sloan Digital Sky Survey. It is found that unobscured and obscured quasars have similar space densities at rest frame 7.8 um, but the ratio Lv(100 um)/Lv(7.8 um) is about three times higher for obscured quasars compared to unobscured, so that far infrared or submm discoveries are dominated by obscured quasars. Quasar source counts for these samples are determined for comparison to the number of submm sources that have been discovered with the SCUBA-2 camera at z ~ 2 using the Lv(100 um)/Lv(7.8 um) results together with the Bootes 7.8 um counts, and we find that only ~ 5% of high redshift submm sources are quasars, including even the most obscured quasars. Illustrative source counts are predicted to z = 10, and we show that existing SCUBA-2 850 um surveys or 2 mm surveys with the Goddard-IRAM Superconducting 2 Millimeter Observer (GISMO) survey camera should already have detected sources at z ~ 10 if quasar and starburst luminosity functions remain the same from z = 2 until z = 10., Accepted for publication in The Astrophysical Journal
- Published
- 2016
47. Gladii Electorales Saxonici
- Author
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John C. Barentine
- Subjects
Stars ,Apparent magnitude ,Serpens ,media_common.quotation_subject ,Astronomy ,BOOTES ,Art ,Galaxy ,Constellation ,media_common - Abstract
This highly contrived figure was devised by Gottfried Kirch in 1684 as an attempt to draw the attention (and patronage) of the Elector of Saxony at the time, Johann Georg III (1647–1691). It consisted of nine unformed stars between visual magnitude + 3. 7 and + 5. 2 in the area where the edges of the traditional figures of Bootes, Serpens, Libra, and Virgo converged; the point where the swords in Kirch’s figure cross is very close to the position of the bright, edge-on galaxy NGC 5746. He published the suggested constellation along with a description of Scutum Sobieski in Acta Eruditorum, the first scientific journal in the region of Europe that later became Germany. Kirch included a lengthy description with his engraving of the new constellation (Fig. 6.1), presented here in its entirety along with an English translation.
- Published
- 2016
- Full Text
- View/download PDF
48. Poetry, Rhetoric, and Science: The Case of Plaustra Bootes
- Author
-
Richard C. Monti
- Subjects
Literature ,Linguistics and Language ,History ,Archeology ,Hierarchy ,Literature and Literary Theory ,Poetry ,business.industry ,media_common.quotation_subject ,Philosophy ,BOOTES ,Sublime ,Language and Linguistics ,Epistemology ,Latin poetry ,Rhetoric ,Natural science ,Diction ,Classics ,business ,media_common - Abstract
[Abstract This article examines the aural qualities of the collocation plaustra Bootes, its application in Latin poetry, and the precepts of rhetorical theory which explain its use. Plaustra Bootes, which occurs frequently, refers to either or both of the circumpolar constellations Ursa Major and Ursa Minor, configured as ‘wagons’, and to Bootes, the ‘Oxman’ who tends them. The case is made that the collocation is a poetic formula characterized by solemnity of diction, and that its application is limited to contexts, usually characterized by highly elaborate rhetoric, which train the attention on matters of natural science and philosophy. The rhetorical theory of the sublime provides the means to explain the pairing of diction and subject matter. It establishes a hierarchy of sublime topics which include philosophy and natural science, and it indicates the appropriate manner to express elevated thought. In this way rhetorical theory raises the question of the place of science in rhetoric and poetry. Implicit in the theory of the sublime is a system of thought in which rhetoric, poetic theory, and science are aligned with each other as representations in different domains of the same reality., Abstract This article examines the aural qualities of the collocation plaustra Bootes, its application in Latin poetry, and the precepts of rhetorical theory which explain its use. Plaustra Bootes, which occurs frequently, refers to either or both of the circumpolar constellations Ursa Major and Ursa Minor, configured as ‘wagons’, and to Bootes, the ‘Oxman’ who tends them. The case is made that the collocation is a poetic formula characterized by solemnity of diction, and that its application is limited to contexts, usually characterized by highly elaborate rhetoric, which train the attention on matters of natural science and philosophy. The rhetorical theory of the sublime provides the means to explain the pairing of diction and subject matter. It establishes a hierarchy of sublime topics which include philosophy and natural science, and it indicates the appropriate manner to express elevated thought. In this way rhetorical theory raises the question of the place of science in rhetoric and poetry. Implicit in the theory of the sublime is a system of thought in which rhetoric, poetic theory, and science are aligned with each other as representations in different domains of the same reality.]
- Published
- 2012
- Full Text
- View/download PDF
49. Multiwavelength observations of GRB afterglows
- Author
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A. J. Castro-Tirado
- Subjects
Physics ,Accretion disc ,Space and Planetary Science ,Astronomy ,Plateau de Bure Interferometer ,Astronomy and Astrophysics ,BOOTES ,Astrophysics ,Gamma-ray burst - Abstract
Multiwavelength observations of gamma-ray burst afterglows are presented, in particular those in the optical and millimetre wavelengths. I will focus on the observations mostly carried out at Spanish ground-based observatories (mainly the 10.4m GTC) and at the Plateau de Bure Interferometer in the French Alps. The importance of global networks of robotic telescopes (like BOOTES, established worldwide) for early time observations in order to put constraints on the physical mechanisms of the GRB early time emission phase is also discussed. The overall observational efforts provide additional clues for a better understanding of the reverse and forward shock. Finally I will report on the Lomonosov/UFFO-p capabilities taking into account its launch in 2012.
- Published
- 2011
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- View/download PDF
50. Deep LOFAR 150 MHz imaging of the Boötes field: Unveiling the faint low-frequency sky
- Author
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H. J. A. Röttgering, Isabella Prandoni, P. N. Best, R. J. van Weeren, Marcus Brüggen, E. Retana-Montenegro, G. Brunetti, and Timothy W. Shimwell
- Subjects
Physics ,Active galactic nucleus ,010308 nuclear & particles physics ,media_common.quotation_subject ,Flux ,Astronomy and Astrophysics ,BOOTES ,Astrophysics::Cosmology and Extragalactic Astrophysics ,LOFAR ,Cosmic variance ,Astrophysics ,Astrophysics - Astrophysics of Galaxies ,01 natural sciences ,Galaxy ,Space and Planetary Science ,Sky ,0103 physical sciences ,Source counts ,010303 astronomy & astrophysics ,media_common - Abstract
We have conducted a deep survey (with a central rms of $55\mu\textrm{Jy}$) with the LOw Frequency ARray (LOFAR) at 120-168 MHz of the Bo\"otes field, with an angular resolution of $3.98^{''}\times6.45^{''}$, and obtained a sample of 10091 radio sources ($5\sigma$ limit) over an area of $20\:\textrm{deg}^{2}$. The astrometry and flux scale accuracy of our source catalog is investigated. The resolution bias, incompleteness and other systematic effects that could affect our source counts are discussed and accounted for. The derived 150 MHz source counts present a flattening below sub-mJy flux densities, that is in agreement with previous results from high- and low- frequency surveys. This flattening has been argued to be due to an increasing contribution of star-forming galaxies and faint active galactic nuclei. Additionally, we use our observations to evaluate the contribution of cosmic variance to the scatter in source counts measurements. The latter is achieved by dividing our Bo\"otes mosaic into 10 non-overlapping circular sectors, each one with an approximate area of $2\:\textrm{deg}^{2}.$ The counts in each sector are computed in the same way as done for the entire mosaic. By comparing the induced scatter with that of counts obtained from depth observations scaled to 150MHz, we find that the $1\sigma$ scatter due to cosmic variance is larger than the Poissonian errors of the source counts, and it may explain the dispersion from previously reported depth source counts at flux densities $S, Comment: A\&A in press. 15 pages, 16 figures
- Published
- 2018
- Full Text
- View/download PDF
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