Search

Your search keyword '"Augustin, R."' showing total 509 results
Start Over Author "Augustin, R."
509 results on '"Augustin, R."'

4. MUSE-ALMA Halos V: Physical properties and environment of z < 1.4 HI quasar absorbers

Author

Hamanowicz, A., Peroux, C., Zwaan, M. A., Rahmani, H., Pettini, M., York, D. G., Klitsch, A., Augustin, R., Krogager, J-K., Kulkarni, V., Fresco, A., Biggs, A. D., Milliard, B., and Vernet, J.

Subjects
Astrophysics - Astrophysics of Galaxies
Abstract

We present results of the MUSE-ALMA Halos, an ongoing study of the Circum-Galactic Medium (CGM) of low redshift galaxies (z < 1.4), currently comprising 14 strong HI absorbers in five quasar fields. We detect 43 galaxies associated with absorbers down to star formation rate (SFR) limits of 0.01-0.1 solar masses/yr, found within impact parameters (b) of 250 kpc from the quasar sightline. Excluding the targeted absorbers, we report a high detection rate of 89 per cent and find that most absorption systems are associated with pairs or groups of galaxies (three to eleven members). We note that galaxies with the smallest impact parameters are not necessarily the closest to the absorbing gas in velocity space. Using a multi-wavelength dataset (UVES/HIRES, HST, MUSE), we combine metal and HI column densities, allowing for derivation of the lower limits of neutral gas metallicity as well as emission line diagnostics (SFR, metallicities) of the ionised gas in the galaxies. We find that groups of associated galaxies follow the canonical relations of N(HI) -- b and W_r(2796) -- b, defining a region in parameter space below which no absorbers are detected. The metallicity of the ISM of associated galaxies, when measured, is higher than the metallicity limits of the absorber. In summary, our findings suggest that the physical properties of the CGM of complex group environments would benefit from associating the kinematics of individual absorbing components with each galaxy member., Comment: Accepted for publication in MNRAS; 23 pages, 25 figures

Published
2019
Full Text
View/download PDF

5. Unveiling the faint ultraviolet Universe

Author

Zanella, A., Zanoni, C., Arrigoni-Battaia, F., Rubin, A., Pala, A., Peroux, C., Augustin, R., Circosta, C., Emsellem, E., George, E., Milakovic, D., van der Burg, R., and Kupfer, T.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Cosmology and Nongalactic Astrophysics, Astrophysics - Astrophysics of Galaxies, Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Solar and Stellar Astrophysics
Abstract

With this paper we participate to the call for ideas issued by the European Space Agency to define the Science Program and plan for space missions from 2035 to 2050. In particular we present five science cases where major advancements can be achieved thanks to space-based spectroscopic observations at ultraviolet (UV) wavelengths. We discuss the possibility to (1) unveil the large-scale structures and cosmic web in emission at redshift <~1.7; (2) study the exchange of baryons between galaxies and their surroundings to understand the contribution of the circumgalactic gas to the evolution and angular-momentum build-up of galaxies; (3) constrain the efficiency of ram-pressure stripping in removing gas from galaxies and its role in quenching star formation; (4) characterize the progenitor population of core-collapse supernovae to reveal the explosion mechanisms of stars; (5) target accreting white dwarfs in globular clusters to determine their evolution and fate. These science themes can be addressed thanks to UV (wavelength range lambda ~ 90 - 350 nm) observations carried out with a panoramic integral field spectrograph (field of view ~ 1 x 1 arcmin^2 ), and medium spectral (R = 4000) and spatial (~ 1" - 3") resolution. Such a UV-optimized instrument will be unique in the coming years, when most of the new large facilities such as the Extremely Large Telescope and the James Webb Space Telescope are optimized for infrared wavelengths., Comment: White paper submitted in response to the ESA call Voyage 2050. Accepted for publication by Experimental Astronomy

Published
2019

6. Emission from the circumgalactic medium: from cosmological zoom-in simulations to multiwavelength observables

Author

Augustin, R., Quiret, S., Milliard, B., Peroux, C., Vibert, D., Blaizot, J., Rasera, Y., Teyssier, R., Frank, S., Deharveng, J. -M., Picouet, V., Martin, D. C., Hamden, E. T., Thatte, N., Santaella, M. Pereira, Routledge, L., and Zieleniewski, S.

Subjects
Astrophysics - Astrophysics of Galaxies
Abstract

We simulate the flux emitted from galaxy halos in order to quantify the brightness of the circumgalactic medium (CGM). We use dedicated zoom-in cosmological simulations with the hydrodynamical Adaptive Mesh Refinement code RAMSES, which are evolved down to z=0 and reach a maximum spatial resolution of 380 $h^{-1}$pc and a gas mass resolution up to 1.8$\times 10^{5} h^{-1} \rm{M}_{\odot}$ in the densest regions. We compute the expected emission from the gas in the CGM using CLOUDY emissivity models for different lines (e.g. Ly$\alpha$, CIV, OVI, CVI, OVIII) considering UV background fluorescence, gravitational cooling and continuum emission. In the case of Ly$\alpha$ we additionally consider the scattering of continuum photons. We compare our predictions to current observations and find them to be in good agreement at any redshift after adjusting the Ly$\alpha$ escape fraction. We combine our mock observations with instrument models for FIREBall-2 (UV balloon spectrograph) and HARMONI (visible and NIR IFU on the ELT) to predict CGM observations with either instrument and optimise target selections and observing strategies. Our results show that Ly$\alpha$ emission from the CGM at a redshift of 0.7 will be observable with FIREBall-2 for bright galaxies (NUV$\sim$18 mag), while metal lines like OVI and CIV will remain challenging to detect. HARMONI is found to be well suited to study the CGM at different redshifts with various tracers., Comment: accepted for publication in MNRAS

Published
2019
Full Text
View/download PDF

13. The timing of recurrence after endoscopic papillectomy

Author

Han, Samuel, primary, Turkeltaub, Joshua A., additional, Jonas, Daniel, additional, Attwell, Augustin R., additional, Duloy, Anna M., additional, Edmundowicz, Steven A., additional, Hammad, Hazem T., additional, Wagh, Mihir S., additional, Wani, Sachin, additional, and Shah, Raj J., additional

Published
2023
Full Text
View/download PDF

21. MUSE-ALMA Haloes - VIII. Statistical study of circumgalactic medium gas

Author

Weng, S., Peroux, C., Karki, A., Augustin, R., Kulkarni, V. P., Szakacs, R., Zwaan, M. A., Klitsch, A., Hamanowicz, A., Sadler, E. M., Biggs, A., Fresco, A. Y., Hayes, M., Howk, J. C., Kacprzak, G. G., Kuntschner, H., Nelson, D., Pettini, M., Weng, S., Peroux, C., Karki, A., Augustin, R., Kulkarni, V. P., Szakacs, R., Zwaan, M. A., Klitsch, A., Hamanowicz, A., Sadler, E. M., Biggs, A., Fresco, A. Y., Hayes, M., Howk, J. C., Kacprzak, G. G., Kuntschner, H., Nelson, D., and Pettini, M.

Abstract

The distribution of gas and metals in the circumgalactic medium (CGM) plays a critical role in how galaxies evolve. The MUSE-ALMA Haloes survey combines MUSE, ALMA, and HST observations to constrain the properties of the multiphase gas in the CGM and the galaxies associated with the gas probed in absorption. In this paper, we analyse the properties of galaxies associated with 32 strong H I Ly- alpha absorbers at redshift 0.2 (SIC) z (SIC) 1.4. We detect 79 galaxies within +/- 500 kms(-1) of the absorbers in our 19 MUSE fields. These associated galaxies are found at physical distances from 5.7 kpc and reach star formation rates as low as 0.1 M-? yr (-1). The significant number of associated galaxies allows us to map their physical distribution on the Av and b plane. Building on previous studies, we examine the physical and nebular properties of these associated galaxies and find the following: (i) 27/32 absorbers have galaxy counterparts and more than 50 per cent of the absorbers have two or more associated galaxies, (ii) the H I column density of absorbers is anticorrelated with the impact parameter (scaled by virial radius) of the nearest galaxy as expected from simulations, (iii) the metallicity of associated galaxies is typically larger than the absorber metallicity, which decreases at larger impact parameters. It becomes clear that while strong H I absorbers are typically associated with more than a single galaxy, we can use them to statistically map the gas and metal distribution in the CGM.

Published
2023

22. MUSE-ALMA Haloes – VIII. Statistical study of circumgalactic medium gas

Author

Weng, S, primary, Péroux, C, additional, Karki, A, additional, Augustin, R, additional, Kulkarni, V P, additional, Szakacs, R, additional, Zwaan, M A, additional, Klitsch, A, additional, Hamanowicz, A, additional, Sadler, E M, additional, Biggs, A, additional, Fresco, A Y, additional, Hayes, M, additional, Howk, J C, additional, Kacprzak, G G, additional, Kuntschner, H, additional, Nelson, D, additional, and Pettini, M, additional

Published
2022
Full Text
View/download PDF

23. MUSE–ALMA haloes VII: survey science goals & design, data processing and final catalogues

Author

Péroux, C, primary, Weng, S, additional, Karki, A, additional, Augustin, R, additional, Kulkarni, V P, additional, Szakacs, R, additional, Klitsch, A, additional, Hamanowicz, A, additional, Fresco, A Y, additional, Zwaan, M A, additional, Biggs, A, additional, Fox, A J, additional, Hayes, M, additional, Howk, J C, additional, Kacprzak, G G, additional, Kassin, S, additional, Kuntschner, H, additional, Nelson, D, additional, and Pettini, M, additional

Published
2022
Full Text
View/download PDF

24. MUSE-ALMA haloes VII : survey science goals & design, data processing and final catalogues

Author

Péroux, C., Weng, S., Karki, A., Augustin, R., Kulkarni, V. P., Szakacs, R., Klitsch, A., Hamanowicz, A., Fresco, A. Y., Zwaan, M. A., Biggs, A., Fox, A. J., Hayes, Matthew J., Howk, J. C., Kacprzak, G. G., Kassin, S., Kuntschner, H., Nelson, D., Pettini, M., Péroux, C., Weng, S., Karki, A., Augustin, R., Kulkarni, V. P., Szakacs, R., Klitsch, A., Hamanowicz, A., Fresco, A. Y., Zwaan, M. A., Biggs, A., Fox, A. J., Hayes, Matthew J., Howk, J. C., Kacprzak, G. G., Kassin, S., Kuntschner, H., Nelson, D., and Pettini, M.

Abstract

The gas cycling in the circumgalactic regions of galaxies is known to be multi-phase. The MUSE–ALMA Haloes survey gathers a large multi-wavelength observational sample of absorption and emission data with the goal to significantly advance our understanding of the physical properties of such CGM gas. A key component of the MUSE–ALMA Haloes survey is the multi-facility observational campaign conducted with VLT/MUSE, ALMA, and HST. MUSE–ALMA Haloes targets comprise 19 VLT/MUSE IFS quasar fields, including 32 zabs <0.85 strong absorbers with measured N(H I) ≥1018 cm−2 from UV-spectroscopy. We additionally use a new complementary HST medium program to characterize the stellar content of the galaxies through a 40-orbit three-band UVIS and IR WFC3 imaging. Beyond the absorber-selected targets, we detect 3658 sources all fields combined, including 703 objects with spectroscopic redshifts. This galaxy-selected sample constitutes the main focus of the current paper. We have secured millimeter ALMA observations of some of the fields to probe the molecular gas properties of these objects. Here, we present the overall survey science goals, target selection, observational strategy, data processing and source identification of the full sample. Furthermore, we provide catalogues of magnitude measurements for all objects detected in VLT/MUSE, ALMA, and HST broad-band images and associated spectroscopic redshifts derived from VLT/MUSE observations. Together, this data set provides robust characterization of the neutral atomic gas, molecular gas and stars in the same objects resulting in the baryon census of condensed matter in complex galaxy structures.

Published
2022
Full Text
View/download PDF

25. MUSE-ALMA haloes VII:survey science goals & design, data processing and final catalogues

Author

Peroux, C., Weng, S., Karki, A., Augustin, R., Kulkarni, V. P., Szakacs, R., Klitsch, A., Hamanowicz, A., Fresco, A. Y., Zwaan, M. A., Biggs, A., Fox, A. J., Hayes, M., Howk, J. C., Kacprzak, G. G., Kassin, S., Kuntschner, H., Nelson, D., Pettini, M., Peroux, C., Weng, S., Karki, A., Augustin, R., Kulkarni, V. P., Szakacs, R., Klitsch, A., Hamanowicz, A., Fresco, A. Y., Zwaan, M. A., Biggs, A., Fox, A. J., Hayes, M., Howk, J. C., Kacprzak, G. G., Kassin, S., Kuntschner, H., Nelson, D., and Pettini, M.

Abstract

The gas cycling in the circumgalactic regions of galaxies is known to be multi-phase. The MUSE-ALMA Haloes survey gathers a large multi-wavelength observational sample of absorption and emission data with the goal to significantly advance our understanding of the physical properties of such CGM gas. A key component of the MUSE-ALMA Haloes survey is the multi-facility observational campaign conducted with VLT/MUSE, ALMA, and HST. MUSE-ALMA Haloes targets comprise 19 VLT/MUSE IFS quasar fields, including 32 z(abs) = 10(18) cm(-2) from UV-spectroscopy. We additionally use a new complementary HST medium program to characterize the stellar content of the galaxies through a 40-orbit three-band UVIS and IR WFC3 imaging. Beyond the absorber-selected targets, we detect 3658 sources all fields combined, including 703 objects with spectroscopic redshifts. This galaxy-selected sample constitutes the main focus of the current paper. We have secured millimeter ALMA observations of some of the fields to probe the molecular gas properties of these objects. Here, we present the overall survey science goals, target selection, observational strategy, data processing and source identification of the full sample. Furthermore, we provide catalogues of magnitude measurements for all objects detected in VLT/MUSE, ALMA, and HST broad-band images and associated spectroscopic redshifts derived from VLT/MUSE observations. Together, this data set provides robust characterization of the neutral atomic gas, molecular gas and stars in the same objects resulting in the baryon census of condensed matter in complex galaxy structures.

Published
2022

26. MUSE-ALMA Haloes – VIII. Statistical study of circumgalactic medium gas.

Author

Weng, S, Péroux, C, Karki, A, Augustin, R, Kulkarni, V P, Szakacs, R, Zwaan, M A, Klitsch, A, Hamanowicz, A, Sadler, E M, Biggs, A, Fresco, A Y, Hayes, M, Howk, J C, Kacprzak, G G, Kuntschner, H, Nelson, D, and Pettini, M

Subjects
GAS distribution, GAS absorption & adsorption, PHYSICAL distribution of goods, COLUMNS
Abstract

The distribution of gas and metals in the circumgalactic medium (CGM) plays a critical role in how galaxies evolve. The MUSE-ALMA Haloes survey combines MUSE, ALMA, and HST observations to constrain the properties of the multiphase gas in the CGM and the galaxies associated with the gas probed in absorption. In this paper, we analyse the properties of galaxies associated with 32 strong |${\rm H\, {\small I}}$| Ly-α absorbers at redshift 0.2 ≲ z ≲ 1.4. We detect 79 galaxies within ±500 kms−1 of the absorbers in our 19 MUSE fields. These associated galaxies are found at physical distances from 5.7 kpc and reach star formation rates as low as 0.1 M⊙ yr−1. The significant number of associated galaxies allows us to map their physical distribution on the Δ v and b plane. Building on previous studies, we examine the physical and nebular properties of these associated galaxies and find the following: (i) 27/32 absorbers have galaxy counterparts and more than 50 per cent of the absorbers have two or more associated galaxies, (ii) the |${\rm H\, {\small I}}$| column density of absorbers is anticorrelated with the impact parameter (scaled by virial radius) of the nearest galaxy as expected from simulations, (iii) the metallicity of associated galaxies is typically larger than the absorber metallicity, which decreases at larger impact parameters. It becomes clear that while strong |${\rm H\, {\small I}}$| absorbers are typically associated with more than a single galaxy, we can use them to statistically map the gas and metal distribution in the CGM. [ABSTRACT FROM AUTHOR]

Published
2023
Full Text
View/download PDF

32. Combination of ERCP-Based Modalities Increases Diagnostic Yield for Biliary Strictures

Author

Samuel, Han, Philip, Tatman, Sanjana, Mehrotra, Sachin, Wani, Augustin R, Attwell, Steven A, Edmundowicz, Brian C, Brauer, Mihir S, Wagh, Hazem T, Hammad, and Raj J, Shah

Subjects
Adult, Cholangiopancreatography, Endoscopic Retrograde, Male, Cholestasis, Microscopy, Confocal, Cytodiagnosis, Constriction, Pathologic, Adenocarcinoma, Middle Aged, Pancreatic Neoplasms, Bile Duct Neoplasms, Humans, Female, In Situ Hybridization, Fluorescence, Aged, Retrospective Studies
Abstract

Biliary stricture evaluation with brush cytology and intraductal forceps biopsy carries a low sensitivity, but the combination of newer modalities may improve sensitivity.To determine whether the addition of advanced modalities increases diagnostic yield of ERCP-based sampling.This single-center retrospective study evaluates patients with biliary strictures sampled using brush cytology. Operating characteristics were calculated for individual and combinations of modalities including cholangioscopy, fluoroscopy- and cholangioscopy-directed intraductal biopsy, fluorescence in situ hybridization (FISH), and confocal laser endomicroscopy. Analyses under Standard Criteria (SC) included malignant results as "positive" and Expanded Criteria (EC) included "suspicious" and "high-grade dysplasia" results as "positive."A total of 614 patients were included, and 354 (57.8%) received brush cytology alone, which had a sensitivity of 38.5% (SC) to 40.3% (EC) and a specificity of 97.8% (EC) to 99.3% (SC). Combining brush cytology with fluoroscopy-guided biopsy (n = 259, 42.2%) had a sensitivity of 62.5% (SC) to 67.9% (EC) and specificity of 90.2% (EC) to 96.7% (SC). Adding FISH to brush cytology had a sensitivity of 84.2% (SC) to 87.5% (EC) and specificity of 54.1% (SC and EC), while cholangioscopy visualization addition resulted in a sensitivity of 80.4% (SC) to 92.2% (EC) and specificity of 67.3% (EC) to 89.1% (SC). There were no significant differences in sensitivity and specificity using SC and EC.Brush cytology has a low sensitivity, but the addition of other modalities increases sensitivity. There was no difference in specificity between the SC and the EC, supporting the inclusion of "suspicious" impressions with malignant results at our center.

Published
2019

33. ESA Voyage 2050 white paper: Unveiling the faint ultraviolet Universe

Author

Zanella, A., Zanoni, C., Arrigoni-Battaia, F., Rubin, A., Pala, A., Peroux, C., Augustin, R., Circosta, C., Emsellem, E., George, E., Milakovic, D., van der Burg, R., Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES)

Subjects
Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics::Galaxy Astrophysics
Abstract

New and unique science opportunities in several different fields of astrophysics are offered by conducting spectroscopic studies of the Universe in the ultraviolet (UV), a wavelength regime that is not accessible from the ground. We present some of the scientific challenges that can be addressed with a space-based mission in 2035 - 2050. (1) By detecting the intergalactic medium in emission it will be possible to unveil the cosmic web, whose existence is predicted by current theories of structure formation, but it has not been probed yet. (2) Observations of the neutral gas distribution (by mapping the Lyman-alpha emission) in low-redshift galaxy cluster members will clarify the efficiency with which ram-pressure stripping removes the gas from galaxies and the role of the environment in quenching star formation. (3) By observing statistical samples of supernovae in the UV it will be possible to characterize the progenitor population of core-collapse supernovae, providing the initial conditions for any forward-modeling simulation and allowing the community to progress in the understanding of the explosion mechanism of stars and the final stages of stellar evolution. (4) Targeting populations of accreting white dwarfs in globular clusters it will be possible to constrain the evolution and fate of these stars and investigate the properties of the most compact systems with the shortest orbital periods which are expected to be the brightest low frequency gravitational wave sources. A UV-optimized telescope (wavelength range ~ 90 - 350 nm), equipped with a panoramic integral field spectrograph with a large field of view (FoV ~ 1 x 1 arcmin^2), with medium spectral (R = 4000) and spatial (~ 1" - 3") resolution will allow the community to simultaneously obtain spectral and photometric information of the targets, and tackle the science questions presented in this paper.

Published
2019

41. Emission from the circumgalactic medium: from cosmological zoom-in simulations to multiwavelength observables

Author

Augustin, R, primary, Quiret, S, additional, Milliard, B, additional, Péroux, C, additional, Vibert, D, additional, Blaizot, J, additional, Rasera, Y, additional, Teyssier, R, additional, Frank, S, additional, Deharveng, J-M, additional, Picouet, V, additional, Martin, D C, additional, Hamden, E T, additional, Thatte, N, additional, Pereira Santaella, M, additional, Routledge, L, additional, and Zieleniewski, S, additional

Published
2019
Full Text
View/download PDF

42. Tu1380 OCCLUSION OF LUMEN-APPOSING METAL STENTS USED FOR TREATMENT OF WALLED-OFF PANCREATIC NECROSIS: RESULTS OF A RETROSPECTIVE TWO CENTER STUDY

Author

Fejleh, M. Phillip, primary, Han, Samuel, additional, Yang, Liu, additional, Marya, Neil B., additional, Phan, Jennifer, additional, Attwell, Augustin R., additional, Brauer, Brian C., additional, Edmundowicz, Steven A., additional, Hammad, Hazem T., additional, Shah, Raj J., additional, Wagh, Mihir S., additional, Wani, Sachin B., additional, Kim, Stephen, additional, Muthusamy, V. Raman, additional, and Sedarat, Alireza, additional

Published
2019
Full Text
View/download PDF

43. Tu1379 BASELINE PROTON PUMP INHIBITOR USE IS ASSOCIATED WITH A LOWER RISK OF BLEEDING AFTER LUMEN-APPOSING METAL STENT PLACEMENT

Author

Han, Samuel, primary, Fejleh, M. Phillip, additional, Attwell, Augustin R., additional, Edmundowicz, Steven A., additional, Hammad, Hazem T., additional, Kim, Stephen, additional, Marya, Neil B., additional, Muthusamy, V. Raman, additional, Sedarat, Alireza, additional, Shah, Raj J., additional, Wagh, Mihir S., additional, Wani, Sachin B., additional, and Brauer, Brian C., additional

Published
2019
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results