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相关论文: PC1643+4631A,B: The Lyman-Alpha Forest at the Edge…

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The distribution of absorption lines in the spectra of distant quasars, called the Lyman-$\alpha$ (Ly-$\alpha$) forest, is a unique probe of cosmology and the intergalactic medium at high redshifts and small scales. The statistical power of…

宇宙学与河外天体物理 · 物理学 2025-07-02 Roger de Belsunce , Mikhail M. Ivanov , James M. Sullivan , Kazuyuki Akitsu , Shi-Fan Chen

We present a spectroscopic redshift measurement of a very bright Lyman break galaxy at z=7.7302+-0.0006 using Keck/MOSFIRE. The source was pre-selected photometrically in the EGS field as a robust z~8 candidate with H=25.0 mag based on…

Absorption spectra of high redshift quasars exhibit an increasingly thick Ly-alpha forest towards z~6. However, the interpretation of these spectra is complicated by the fact that the Ly-alpha optical depth is already large for neutral…

天体物理学 · 物理学 2015-05-13 Stuart Wyithe , James Bolton , Martin Haehnelt

In light of recent successes in measuring baryon acoustic oscillations in quasar absorption using the Lyman $\alpha$ (Ly$\alpha$) transition, I explore the possibility of using the 1548\AA\ transition of triply ionized carbon (C IV) as a…

宇宙学与河外天体物理 · 物理学 2015-06-19 Matthew M. Pieri

Quasar spectra provide a unique opportunity to investigate the intergalactic medium at high redshifts. The spectral analysis of the Ly$\alpha$ forest allows us to constrain the effective equation of state of the intergalactic medium and its…

宇宙学与河外天体物理 · 物理学 2019-04-02 K N Telikova , S A Balashev , P S Shternin

We present STIS 7km/s resolution data of the Ly-a forest toward PKS0405-123 (z=0.574). We make two samples. The strong sample (60 systems) has column density logNHI>13.3 over 0.002<z<0.423, and the weak sample (44) has logNHI>13.1 at…

天体物理学 · 物理学 2008-11-26 G. M. Williger , S. R. Heap , R. J. Weymann , R. Dave , E. Ellingson , R. F. Carswell , T. M. Tripp , E. B. Jenkins

We use the Ly-$\alpha$ Mass Association Scheme (LyMAS; Peirani et al. 2014) to predict cross-correlations at $z=2.5$ between dark matter halos and transmitted flux in the Ly-$\alpha$ forest, and compare to cross-correlations measured for…

Probing the size and shape of the absorbers that lie in front of the QSOs, in particular the Ly alpha forest, we analyze 785 absorption lines in spectra of five QSOs in close groupings: a pair and a triplet. Both QSO groups have been…

天体物理学 · 物理学 2009-10-30 Arlin Crotts , Yihu Fang

Absorption spectroscopy of gravitationally lensed quasars (GLQs) enables study of spatial variations in the interstellar and/or circumgalactic medium of foreground galaxies. We report observations of 4 GLQs, each with two images separated…

We present new GHRS observations of Lyman alpha absorption lines associated with a group of galaxies towards the QSO 1545+2101. We have identified eight distinct Lyman alpha absorption features in the spectrum of QSO 1545+2101 at a mean…

天体物理学 · 物理学 2009-10-31 A. Ortiz-Gil , K. M. Lanzetta , J. K. Webb , X. Barcons , A. Fernandez-Soto

Ultraviolet spectrographs aboard the Hubble Space Telescope (HST) and the Far Ultraviolet Spectroscopic Explorer (FUSE) have proved their value as sensitive probes of the low-density intergalactic medium (IGM) at low redshifts (z < 0.1).…

天体物理学 · 物理学 2007-05-23 J. Michael Shull

We present preliminary results on the low-redshift Lyman alpha forest as based on STIS spectra of 3C 273. A total of 121 intergalactic Lyman alpha-absorbing systems were detected, of which 60 are above the 3.5 sigma completness limit, log…

天体物理学 · 物理学 2007-05-23 S. R. Heap , G. M. Williger , R. Dave , R. J. Weymann , E. B. Jenkins , T. M. Tripp

We present the first detection of a correlation between the Lyman-$\alpha$ forest and cosmic microwave background (CMB) lensing. For each Lyman-$\alpha$ forest in SDSS-III/BOSS DR12, we correlate the one-dimensional power spectrum with the…

宇宙学与河外天体物理 · 物理学 2016-11-15 Cyrille Doux , Emmanuel Schaan , Eric Aubourg , Ken Ganga , Khee-Gan Lee , David N. Spergel , Julien Tréguer

We present the first science results from our Hubble Space Telescope Survey for Lyman limit absorption systems (LLS) using the low dispersion spectroscopic modes of the Advanced Camera for Surveys and the Wide Field Camera 3. Through an…

宇宙学与河外天体物理 · 物理学 2015-06-04 John M. O'Meara , J. Xavier Prochaska , Gabor Worseck , Hsiao-Wen Chen , Piero Madau

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…

天体物理学 · 物理学 2009-10-31 J. Scott , J. Bechtold , A. Dobrzycki , V. Kulkarni

We derive the transverse flux correlation function in the Lyman-alpha forest at z~2.1 from VLT-FORS observations of a total of 32 pairs of quasars. The shape and correlation length of the transverse correlation function are in good…

天体物理学 · 物理学 2007-05-23 F. Coppolani , P. Petitjean , F. Stoehr , E. Rollinde , C. Pichon , S. Colombi , M. Haehnelt , B. Carswell , R. Teyssier

The decline in abundance of Lyman-$\alpha$ (Ly$\alpha$) emitting galaxies at $z \gtrsim 6$ is a powerful and commonly used probe to constrain the progress of cosmic reionization. We use the CoDaII simulation, which is a radiation…

We present the survey design and initial results from the Parallel Ionizing Emissivity (PIE) survey. PIE is a large HST survey designed to detect Lyman continuum (LyC) emitting galaxies at 3.1$<$ z $<$3.5 and stack their images in order to…

A variety of independent observational studies have now reported a significant decline in the fraction of Lyman-break galaxies which exhibit Ly-a emission over the redshift interval z=6-7. In combination with the strong damping wing…

宇宙学与河外天体物理 · 物理学 2015-06-11 James S. Bolton , Martin G. Haehnelt

We have obtained high resolution (FWHM = 4.4 km/s) Keck spectra of images A and C of the gravitationally lensed QSO Q1422+231. The images are separated by 1.3" on the sky. In an absorption system at z = 3.538 gas column density variations…

天体物理学 · 物理学 2007-05-23 Michael Rauch , Wallace L. W. Sargent , Thomas A. Barlow
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