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FLASHES Survey. I. Integral Field Spectroscopy of the CGM around 48 z ≃ 2.3–3.1 QSOs

O'Sullivan, Donal B. and Martin, Christopher and Matuszewski, Mateusz and Hoadley, Keri and Hamden, Erika and Neill, James D. and Lin, Zeren and Parihar, Prachi (2020) FLASHES Survey. I. Integral Field Spectroscopy of the CGM around 48 z ≃ 2.3–3.1 QSOs. Astrophysical Journal, 894 (1). Art. No. 3. ISSN 1538-4357. doi:10.3847/1538-4357/ab838c.

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We present the pilot study of the Fluorescent Lyman-Alpha Structures in High-z Environments Survey; the largest integral field spectroscopy survey to date of the circumgalactic medium at z = 2.3–3.1. We observed 48 quasar fields with the Palomar Cosmic Web Imager to an average (2σ) limiting surface brightness of 6 × 10⁻¹⁸ erg s⁻¹ cm⁻² arcsec⁻² (in a 1'' aperture and ~20 Å bandwidth). Extended H I Lyα emission is discovered around 37/48 of the observed quasars, ranging in projected radius from 14 to 55 proper kiloparsecs (pkpc), with one nebula exceeding 100 pkpc in effective diameter. The dimming-adjusted circularly averaged surface brightness profile peaks at 1 × 10⁻¹⁵ erg s⁻¹ cm⁻² arcsec⁻² at R⊥ ~ 20 pkpc and integrated luminosities range from 0.4 to 9.4 × 10⁴³ erg s⁻¹. The emission appears to have an eccentric morphology and an average covering factor of ~30%–40% at small radii. On average, the nebular spectra are redshifted with respect to both the systemic redshift and Lyα peak of the quasar spectrum. The integrated spectra of the nebulae mostly have single- or double-peaked profiles with global dispersions ranging from 143 to 708 km s⁻¹, though the individual Gaussian components of lines with complex shapes mostly have dispersions ≤400 km s⁻¹, and the flux-weighted velocity centroids of the lines vary by thousands of km s⁻¹ with respect to the QSO redshifts. Finally, the root-mean-square velocities of the nebulae are found to be consistent with those expected from gravitational motions in dark matter halos of mass Log₁₀(M_h[M⊙]) ≃ 12.2^(+0.7)_(-1.2). We compare these results to existing surveys at higher and lower redshift.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Martin, Christopher0000-0002-8650-1644
Hoadley, Keri0000-0002-8636-3309
Neill, James D.0000-0002-0466-1119
Additional Information:© 2020 The American Astronomical Society. Received 2019 November 23; revised 2020 March 11; accepted 2020 March 24; published 2020 April 29. This work was supported by the National Science Foundation (NSF Award Number 1716907). The authors would like to thank Chuck Steidel (California Institute of Technology) and Ryan Trainor (Franklin & Marshall College) for their insightful discussions and help with target selection, as well as Sebastiano Cantalupo (ETH Zürich) and Heather Knutson (Caltech). We would also like to thank the staff at Palomar Observatory for their continuous support over nearly seventy nights of observations since 2014. Finally, we would like to thank our reviewer for their time, effort, and thoughtful feedback.
Group:Astronomy Department
Funding AgencyGrant Number
Subject Keywords:Galaxies ; Galaxy evolution ; Circumgalactic medium ; Intergalactic medium ; Quasars ; Galaxy environments
Issue or Number:1
Classification Code:Unified Astronomy Thesaurus concepts: Galaxies (573); Galaxy evolution (594); Circumgalactic medium (1879); Intergalactic medium (813); Quasars (1319); Galaxy environments (2029)
Record Number:CaltechAUTHORS:20200504-124507700
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Official Citation:Donal B. O'Sullivan et al 2020 ApJ 894 3
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:102978
Deposited By: Tony Diaz
Deposited On:04 May 2020 20:07
Last Modified:16 Nov 2021 18:17

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