Publications associées à Sirius

MOSEL Survey: JWST Reveals Major Mergers/strong Interactions Drive the Extreme Emission Lines in the Early Universe

Extreme emission line galaxies (EELGs), where nebular emissions contribute 30%-40% of the flux in certain photometric bands, are ubiquitous in the early Universe (z > 6). We utilize deep NIRCam imaging from the JWST Advanced Deep Extragalactic Survey (JADE ...

Iop Publishing Ltd2023

To grow old and peculiar: Survey of anomalous variable stars in M80 with age determinations using K2 and Gaia

Henryka Ewa Netzel

The globular cluster Messier 80 was monitored by the Kepler space telescope for 80 days during the K2 mission. Continuous, high-precision photometry of such an old, compact cluster allows us for studies of its variable star population in unprecedented deta ...

Edp Sciences S A2023

The eta Aquilae System: Radial Velocities and Astrometry in Search of eta Aql B

Richard Irving Anderson

The classical Cepheid eta Aql was not included in past Leavitt Law work because of a presumed complicating orbit due to a known B9.8V companion. To determine the orbit of eta Aql B, we analyze a significant number of radial velocity (RV) measurements from ...

2022

Extended main sequence turnoffs in open clusters as seen by Gaia - II. The enigma of NGC 2509

Carmela Lardo

We investigate the morphology of the colour-magnitude diagram (CMD) of the open cluster NGC 2509 in comparison with other Galactic open clusters of similar age using Gaia photometry. At similar to 900 Myr Galactic open clusters in our sample all show an ex ...

OXFORD UNIV PRESS2020

A High Space Density of Luminous Ly alpha Emitters at z similar to 6.5

Hakim Atek, Patrick Mccarthy

We present the results of a systematic search for Ly alpha emitters (LAEs) at 6 less than or similar to z less than or similar to 7.6 using the HST WFC3 Infrared Spectroscopic Parallel (WISP) Survey. Our total volume over this redshift range is similar to ...

Iop Publishing Ltd2017

Evaluating the effect of stellar multiplicity on the point spread function of space-based weak lensing surveys

Frédéric Courbin, Georges Meylan, Thibault Adrien Kuntzer

The next generation of space-based telescopes used for weak lensing surveys will require exquisite point spread function (PSF) determination. Previously negligible effects may become important in the reconstruction of the PSF, in part because of the improv ...

Edp Sciences S A2016

Gaia Data Release 1 Summary of the astrometric, photometric, and survey properties

Stephan Morgenthaler, Mikaël Martino, Shuangqing Liao

Context. At about 1000 days after the launch of Gaia we present the first Gaia data release, Gaia DR1, consisting of astrometry and photometry for over 1 billion sources brighter than magnitude 20.7. Aims. A summary of Gaia DR1 is presented along with illu ...

EDP Sciences2016

SPIDERS: the spectroscopic follow-up of X-ray-selected clusters of galaxies in SDSS-IV

Jean-Paul Richard Kneib

SPIDERS (The SPectroscopic IDentification of eROSITA Sources) is a programme dedicated to the homogeneous and complete spectroscopic follow-up of X-ray active galactic nuclei and galaxy clusters over a large area (similar to 7500 deg(2)) of the extragalact ...

Oxford Univ Press2016

The Lyman alpha reference sample VII. Spatially resolved H alpha kinematics

Hakim Atek

We present integral field spectroscopic observations with the Potsdam Multi-Aperture Spectrophotometer of all 14 galaxies in the z similar to 0.1 Lyman Alpha Reference Sample (LARS). We produce 2D line-of-sight velocity maps and velocity dispersion maps fr ...

Edp Sciences S A2016

THE LYMAN ALPHA REFERENCE SAMPLE V. THE IMPACT OF NEUTRAL ISM KINEMATICS AND GEOMETRY ON Ly alpha ESCAPE

Hakim Atek

We present high-resolution far-UV spectroscopy of the 14 galaxies of the Ly alpha Reference Sample; a sample of strongly star-forming galaxies at low redshifts (0.028 < z < 0.18). We compare the derived properties to global properties derived from multi-ba ...

American Astronomical Society2015

The Lyman Alpha Reference Sample. Ii. Hubble Space Telescope Imaging Results, Integrated Properties, And Trends

Hakim Atek

We report new results regarding the Ly alpha output of galaxies, derived from the Lyman Alpha Reference Sample, and focused on Hubble Space Telescope imaging. For 14 galaxies we present intensity images in Ly alpha, H alpha, and UV, and maps of H alpha/H b ...

American Astronomical Society2014

Star formation histories, extinction, and dust properties of strongly lensed z similar to 1.5-3 star-forming galaxies from the Herschel Lensing Survey

Jean-Paul Richard Kneib, Johan Richard

Context. Multi-wavelength, optical to IR/submm observations of strongly lensed galaxies identified by the Herschel Lensing Survey are used to determine the physical properties of high-redshift star-forming galaxies close to or below the detection limits of ...

EDP Sciences2014

Physical properties and evolutionary state of the Lyman alpha emitting starburst galaxy IRAS 08339+6517

Hakim Atek

Context. Though Ly alpha emission is one of the most used tracers of massive star formation at high redshift, it is strongly affected by neutral gas radiation transfer effects. A correct understanding of these effects is required to properly quantify the s ...

EDP Sciences2014

Influence of physical galaxy properties on Ly alpha escape in star-forming galaxies

Jean-Paul Richard Kneib, Hakim Atek

Context. Among the different observational techniques used to select high-redshift galaxies, the hydrogen recombination line Lyman-alpha (Ly alpha) is of particular interest because it gives access to the measurement of cosmological quantities such as the ...

EDP Sciences2014

Spectroscopy of extended Ly alpha envelopes around z=4.5 quasars

Frédéric Courbin, Pierre North, Alexander Patrick Eigenbrod

What are the frequency, shape, kinematics, and luminosity of Ly alpha envelopes surrounding radio-quiet quasars at high redshift, and is the luminosity of these envelopes related to that of the quasar or not? As a first step towards answering these questio ...

2012

COSMOGRAIL: the COSmological MOnitoring of GRAvItational Lenses X. Modeling based on high-precision astrometry of a sample of 25 lensed quasars: consequences for ellipticity, shear, and astrometric anomalies

Frédéric Courbin, Georges Meylan

Gravitationally lensed quasars can be used as powerful cosmological and astrophysical probes. We can (i) infer the Hubble constant H-0 based on the so-called time-delay technique, (ii) unveil substructures along the line-of-sight toward distant galaxies, a ...

2012

Evolution of the observed Ly alpha luminosity function from z=6.5 to z=7.7: evidence for the epoch of reionization?

Jean-Paul Richard Kneib, Frédéric Courbin, Benjamin Yvan Alexandre Clement

Aims. Ly alpha emitters (LAEs) can be detected out to very high redshifts during the epoch of reionization. The evolution of the LAE luminosity function with redshift is a direct probe of the Ly alpha transmission of the intergalactic medium (IGM), and the ...

2012

The simulated 21 cm signal during the epoch of reionization: full modeling of the Ly-alpha pumping

Yves Revaz

The 21 cm emission of neutral hydrogen is the most promising probe of the epoch of reionization (EoR). In the next few years, the SKA pathfinders will provide statistical measurements of this signal, such as its power spectrum. Within one decade, SKA shoul ...

2009

Deep optical spectroscopy of extended Ly alpha emission around three radio-quiet z=4.5 quasars

Frédéric Courbin, Pierre North, Alexander Patrick Eigenbrod

We report the first results of a spectroscopic search for Ly alpha envelopes around three z similar to 4.5 radio-quiet quasars. Our observational strategy adopts the FORS2 spectrograph mounted to the UT1 of the Very Large Telescope (VLT) in the multi-slit ...

2008