Damped Lyman-alpha Absorbers from Sloan Digital Sky Survey DR16Q with Gaussian processes

Abstract

We present a new catalogue of Damped Lyman-$\alpha$ absorbers from SDSS DR16Q, as well as new estimates of their statistical properties. Our estimates are computed with the Gaussian process models presented in Garnett et al. (2017); Ho et al. (2020) with an improved model for marginalising uncertainty in the mean optical depth of each quasar. We compute the column density distribution function (CDDF) at $2<z<5$, the line density ($\text{d}N/\text{d}X$), and the neutral hydrogen density (${\Omega }_{\text{DLA}}$). Our Gaussian process model provides a posterior probability distribution of the number of DLAs per spectrum, thus allowing unbiased probabilistic predictions of the statistics of DLA populations even with the noisiest data. We measure a non-zero column density distribution function for $N_{\text{HI}}<3\times 10^{22}{\text{cm}}^{-2}$ with $95\%$ confidence limits, and $N_{\text{HI}}\lesssim 10^{22}{\text{cm}}^{-2}$ for spectra with signal-to-noise ratios $>4$. Our results for DLA line density and total hydrogen density are consistent with previous measurements. Despite a small bias due to the poorly measured blue edges of the spectra, we demonstrate that our new model can measure the DLA population statistics when the DLA is in the Lyman-$\beta$ forest region. We verify our results are not sensitive to the signal-to-noise ratios and redshifts of the background quasars although a residual correlation remains for detections from $z_{\text{QSO}}<2.5$, indicating some residual systematics when applying our models on very short spectra, where the SDSS spectral observing window only covers part of the Lyman-$\alpha$ forest.

arXiv comment21 pages, 19 figures, 9 tables. Minor changes to match version published in MNRAS. Codes are available at https://github.com/jibanCat/gp_dla_detection_dr16q_public

References in corpus (47)

• The Eleventh and Twelfth Data Releases of the Sloan Digital Sky Survey: Final Data from SDSS-III
• SDSS-III: Massive Spectroscopic Surveys of the Distant Universe, the Milky Way Galaxy, and Extra-Solar Planetary Systems
• The Baryon Oscillation Spectroscopic Survey of SDSS-III
• The SDSS-IV extended Baryon Oscillation Spectroscopic Survey: Overview and Early Data
• The Sloan Digital Sky Survey Quasar Catalog: Sixteenth Data Release
• The Sloan Digital Sky Survey Quasar Catalog: Fourteenth Data Release
• Recovery of the Power Spectrum of Mass Fluctuations from Observations of the Lyman-alpha Forest
• The SDSS Damped Lya Survey: Data Release 3
• The Linear Theory Power Spectrum from the Lyman-alpha Forest in the Sloan Digital Sky Survey
• On the Kinematics of the Damped Lyman Alpha Protogalaxies
• The Observed Probability Distribution Function, Power Spectrum, and Correlation Function of the Transmitted Flux in the Lyman-alpha Forest
• Column density distribution and cosmological mass density of neutral gas: Sloan Digital Sky Survey-III Data Release 9
• On the (Non)Evolution of HI Disks over Cosmic Time
• Damped Lyman alpha absorbers at high redshift -- large disks or galactic building blocks?
• Evolution of the cosmological mass density of neutral gas from Sloan Digital Sky Survey II - Data Release 7
• Damped Lyman Alpha Systems in Galaxy Formation Simulations
• The Neutral Hydrogen Cosmological Mass Density at z=5
• The ESO UVES Advanced Data Products Quasar Sample - II. Cosmological Evolution of the Neutral Gas Mass Density
• The one-dimensional power spectrum from the SDSS DR14 Ly$\alpha$ forests
• The large-scale cross-correlation of Damped Lyman Alpha Systems with the Lyman Alpha Forest: First Measurements from BOSS
• A physical upper limit on the HI column density of gas clouds
• An improved measurement of the flux distribution of the Ly-alpha forest in QSO absorption spectra: the effect of continuum fitting, metal contamination and noise properties
• Physical effects on the Lyman-alpha forest flux power spectrum: damping wings, ionizing radiation fluctuations, and galactic winds
• Dissecting the properties of optically-thick hydrogen at the peak of cosmic star formation history
• Predictions for the relation between strong HI absorbers and galaxies at redshift 3
• The Nature of Damped Lyman Alpha Systems and Their Hosts in the Standard Cold Dark Matter Universe
• The Lyman-alpha forest power spectrum from the XQ-100 Legacy Survey
• Reproducing the Kinematics of Damped Lyman-alpha Systems
• The BOSS Lyman-alpha Forest Sample from SDSS Data Release 9
• Deep Learning of Quasar Spectra to Discover and Characterize Damped Lya Systems
• The SDSS-DR12 large-scale cross-correlation of Damped Lyman Alpha Systems with the Lyman Alpha Forest
• Statistical properties of damped Lyman-alpha systems from Sloan Digital Sky Survey DR12
• Testing Cosmological Models Against the Abundance of Damped Lyman-Alpha Absorbers
• Simulating the effect of high column density absorbers on the one-dimensional Lyman-alpha forest flux power spectrum
• Classification of Broad Absorption Line Quasars with a Convolutional Neural Network
• Correlations in the three-dimensional Lyman-alpha forest contaminated by high column density absorbers
• The effect of (strong) discrete absorption systems on the lyman alpha forest flux power spectrum
• Detecting Damped Lyman-$\alpha$ Absorbers with Gaussian Processes
• The effect of dust bias on the census of neutral gas and metals in the high-redshift Universe due to SDSS-II quasar colour selection
• Detecting Multiple DLAs per Spectrum in SDSS DR12 with Gaussian Processes
• Sub-damped Lyman alpha systems in the XQ-100 survey I -- Identification and contribution to the cosmological HI budget
• Measurements of effective optical depth in the Ly$\alpha$ forest from the BOSS DR12 Quasar sample
• Bias of Damped Lyman-$\alpha$ systems from their cross-correlation with CMB lensing
• Bayesian methods for fitting Baryon Acoustic Oscillations in the Lyman-$\alpha$ forest
• Testing Galaxy Formation Simulations with Damped Lyman-$\alpha$ Abundance and Metallicity Evolution
• Constraining the Halo Mass of Damped Ly$\alpha$ Absorption Systems (DLAs) at $z=2-3.5$ using the Quasar-CMB Lensing Cross-correlation
• Automated Measurement of Quasar Redshift with a Gaussian Process

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