English
Related papers

Related papers: Extreme UV QSOs

200 papers

A sample of 8 QSOs with 1.7 < z_em < 3.7 has been observed with VLT/UVES at a typical resolution 45000 and S/N~40-50. Thanks to the two-arm design of the spectrograph, a remarkable efficiency has been achieved below 400nm and above 800nm,…

Astrophysics · Physics 2007-05-23 S. Cristiani , S. Bianchi , S. D'Odorico , T. -S. Kim

We use six different cosmological models to study the recently-released compilation of X-ray and UV flux measurements of 2038 quasars (QSOs) which span the redshift range $0.009 \leq z \leq 7.5413$. We find, for the full QSO data set, that…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-14 Narayan Khadka , Bharat Ratra

Aims: In this work the luminosity function of QSOs is measured in the redshift range 3.5<z<5.2 for the absolute magnitude interval -21<M_{145}<-28. The determination of the faint end of the luminosity function at these redshifts provides…

Astrophysics · Physics 2009-11-11 F. Fontanot , S. Cristiani , P. Monaco , M. Nonino , E. Vanzella , W. N. Brandt , A. Grazian , J. Mao

We report the detection of 5 newly identifed Lyman-continuum (LyC) leaker candidates at redshifts 0.99-1.42 in the AstroSat UV Deep Field South F154W image. We derive physical properties of these galaxies using a combination of…

Astrophysics of Galaxies · Physics 2025-03-13 Soumil Maulick , Kanak Saha , Michael J. Rutkowski

This paper reports on the extreme ultraviolet (EUV) spectrum of three low redshift ($z \sim 0.6$) radio loud quasars, 3C 95, 3C 57 and PKS 0405-123. The spectra were obtained with the Cosmic Origins Spectrograph (COS) of the Hubble Space…

Astrophysics of Galaxies · Physics 2016-04-27 Brian Punsly , Cormac Reynolds , Paola Marziani , Christopher P. O'Dea

The Lyman-$\alpha$ (Ly$\alpha$) emission line has been ubiquitously used to confirm and study high redshift galaxies. We report on the line morphology as seen in the 2D spectra from the VIMOS Ultra Deep Survey in a sample of 914 Ly$\alpha$…

Submillimeter lines of CN, NO, CO+ and SO+, and upper limits on SH+ and N2O are observed with the James Clerk Maxwell Telescope in two high-mass and up to nine low-mass young stellar objects and compared with chemical models. Constant…

We explore the properties of high-redshift Lyman-alpha emitters (LAE), and their link with the Lyman-Break galaxy population (LBG), using a semi-analytic model of galaxy formation that takes into account resonant scattering of Lya photons…

Astrophysics of Galaxies · Physics 2015-06-24 T. Garel , J. Blaizot , B. Guiderdoni , L. Michel-Dansac , M. Hayes , A. Verhamme

The Shocked POststarburst Galaxy Survey (SPOGS) aims to identify galaxies in the transitional phase between actively star-forming and quiescence with nebular lines that are excited from shocks rather than star formation processes. We…

In this proceeding we present the results from a study of very high-redshift galaxies with the newly commissioned Wide Field Camera 3 on the Hubble Space Telescope. With the deepest near-infrared data ever taken, we discovered 31 galaxies…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Steven L. Finkelstein

We present UV luminosity functions (LFs) at 1500 Angstrom derived from the HST Early Release Science WFC3/UVIS data acquired over ~50 arcmin^2 of the GOODS-South field. The LFs are determined over the entire redshift range z=0.75-2.5 using…

Cosmology and Nongalactic Astrophysics · Physics 2010-12-01 P. A. Oesch , R. J. Bouwens , C. M. Carollo , G. D. Illingworth , D. Magee , M. Trenti , M. Stiavelli , M. Franx , I. Labbe , P. G. van Dokkum

We provide a systematic measurement of the rest-frame UV continuum slope beta over a wide range in redshift (z~2-6) and rest-frame UV luminosity (0.1-2L*) to improve estimates of the SFR density at high redshift. We utilize the deep optical…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 R. J. Bouwens , G. D. Illingworth , M. Franx , R-R. Chary , G. R. Meurer , C. J. Conselice , H. Ford , M. Giavalisco , P. van Dokkum

[Abridged] We present a physical model for the evolution of the ultraviolet (UV) luminosity function (LF) of high-z galaxies taking into account in a self-consistent way their chemical evolution and the associated evolution of dust…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-31 Zhen-Yi Cai , Andrea Lapi , Alessandro Bressan , Gianfranco De Zotti , Mattia Negrello , Luigi Danese

We discuss the UV, optical, and IR properties of the SDSS sources detected by GALEX as part of its All-sky Imaging Survey Early Release Observations. Virtually all of the GALEX sources in the overlap region are detected by SDSS. GALEX…

Aims. The aim of this work is to constrain the evolution of the fraction of Lya emitters among UV selected star forming galaxies at 2<z<6, and to measure the stellar escape fraction of Lya photons over the same redshift range. Methods. We…

We use new studies of the cosmic evolution of star-forming galaxies to estimate the production rate of ionizing photons from hot, massive stars at low and intermediate redshifts. The luminosity function of blue galaxies in the Canada-France…

Astrophysics · Physics 2015-06-24 E. Giallongo , A. Fontana , P. Madau

Lyman $\alpha$ (Ly$\alpha$) is now routinely used as a tool for studying high-redshift galaxies and its resonant nature means it can trace neutral hydrogen around star-forming galaxies. Integral field spectrograph measurements of…

The diffuse far-ultraviolet (FUV) continuum radiation "longward" of Ly-alpha (1216A) is well known to correlate with the dust emission at 100 um. However, it has been claimed that the FUV continuum background "shortward" of Ly-alpha shows…

Astrophysics of Galaxies · Physics 2015-06-16 Kwang-Il Seon

We have compiled a catalog of optically-selected quasars with simultaneous observations in UV/optical and X-ray bands by the Swift Gamma Ray Burst Explorer. Objects in this catalog are identified by matching the Swift pointings with the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Jian Wu , Daniel Vanden Berk , Dirk Grupe , Scott Koch , Jonathan Gelbord , Donald P. Schneider , Caryl Gronwall , Sarah Wesolowski , Blair L. Porterfield

A homogeneous sample of 99 moderate resolution QSO spectra at z > 1.7 were presented in Paper I, including 39 previously unpublished spectra from the Multiple Mirror Telescope. The statistics of the Lyman alpha forest were discussed. In…

Astrophysics · Physics 2009-10-31 J. Scott , J. Bechtold , A. Dobrzycki , V. Kulkarni