An extremely metal-poor Lyman $\alpha$ emitter candidate at $z=6$ revealed through absorption spectroscopy

Abstract

We report the discovery of a Lyman $\alpha$ emitter (LAE) candidate in the immediate foreground of the quasar PSO J158-14 at $z_{\mathrm{QSO}}=6.0685$ at a projected distance $\sim 29\mathrm{pkpc}$ that is associated with an extremely metal-poor absorption system. This system was found in archival observations of the quasar field with the Very Large Telescope/Multi-Unit Spectroscopic Explorer (VLT/MUSE) and was previously missed in searches of absorption systems using quasar absorption line spectroscopy as it imparts no detectable metal absorption lines on the background quasar spectrum. The detected Ly$\alpha$ emission line at a redshift of $z_{\mathrm{LAE}}=6.0323$ is well aligned with the outer edge of the quasar's proximity zone and can plausibly cause its observed damping wing if it is associated with a proximate sub-damped Ly$\alpha$ absorption system with a column density of $\log N_{\mathrm{HI}}/{\mathrm{cm}}^{-2}\approx 19.7$. A $>10$ hour medium-resolution spectrum of the quasar observed with the Magellan/Folded-port InfraRed Echellette (FIRE) and VLT/X-Shooter spectrographs reveals a metallicity constraint of $[Z/H]<-3$. Such low metallicity makes this system an extremely metal-poor galaxy candidate and provides an exciting site to study possible signatures of Population III stars.

10 pages, 4 figures

References in corpus (33)

• Cosmic Star Formation History
• The MUSE second-generation VLT instrument
• Primordial Star Formation under the Influence of Far Ultraviolet Radiation: 1540 Cosmological Halos and the Stellar Mass Distribution
• Hydrogen reionisation ends by $z=5.3$: Lyman-$\alpha$ optical depth measured by the XQR-30 sample
• Population III stars: hidden or disappeared ?
• Velocity-Metallicity Correlation for high-z DLA Galaxies: Evidence for a Mass-Metallicity Relation?
• A Significantly Neutral Intergalactic Medium Around the Luminous z=7 Quasar J0252-0503
• A downturn in intergalactic CIV as redshift 6 is approached
• Diagnostics for PopIII galaxies and Direct Collapse Black Holes in the early universe
• The JWST-PRIMAL Legacy Survey. A JWST/NIRSpec reference sample for the physical properties and Lyman-$\alpha$ absorption and emission of $\sim 500$ galaxies at $z=5.5-13.4$
• Extremely metal-poor gas at a redshift of 7
• JWST-JADES. Possible Population III signatures at z=10.6 in the halo of GN-z11
• Spectroscopic properties of luminous Lyman-α emitters at $z\approx 6-7$ and comparison to the Lyman-break population
• XQR-30: the ultimate XSHOOTER quasar sample at the reionization epoch
• An extremely metal poor star complex in the reionization era: Approaching Population III stars with JWST
• Mapping the Lyman-Alpha Emission Around a z~6.6 QSO with MUSE: Extended Emission and a Companion at Close Separation
• Investigating Nearby Star-Forming Galaxies in the Ultraviolet with HST/COS Spectroscopy. I: Spectral Analysis and Interstellar Abundance Determinations
• Chronicling the reionization history at $6\lesssim z\lesssim 7$ with emergent quasar damping wings
• Damping Wing-Like Features in the Stacked Ly$\alpha$ Forest: Potential Neutral Hydrogen Islands at $z<6$
• The connection between metallicity and metal-line kinematics in (sub-)damped Lyman-alpha systems
• Damping wings in the Lyman-α forest: a model-independent measurement of the neutral fraction at 5.4<z<6.1
• The XQR-30 Metal Absorber Catalog: 778 Absorption Systems Spanning 2 < z < 6.5
• The evolution of the Si IV content in the Universe from the epoch of reionization to cosmic noon
• The Challenges of Identifying Population III Stars in the Early Universe
• Evidence of First Stars-enriched Gas in High-redshift Absorbers
• First Co-spatial Comparison of Stellar, Neutral-, and Ionized-gas Metallicities in a metal-rich galaxy: M83
• New quasar proximity zone size measurements at $z\sim 6$ using the enlarged XQR-30 sample
• Evidence of Pop~III stars' chemical signature in neutral gas at z~6. A study based on the E-XQR-30 spectroscopic sample
• Sub-damped Lyman alpha systems in the XQ-100 survey II -- Chemical evolution at 2.4<z<4.3
• Chemical Diagnostics to Unveil Environments Enriched by First Stars
• Towards ultra metal-poor DLAs: linking the chemistry of the most metal-poor DLA to the first stars
• Detecting and Characterizing Young Quasars. III. The Impact of Gravitational Lensing Magnification
• A survey of extremely metal-poor gas at cosmic noon: evidence of elevated [O/Fe]

Cited by in corpus (2)

• Quasar lifetime measurements from extended Ly$\alpha$ nebulae at $z\sim 6$
• Detailed Abundance Determination of Metal-Poor Stars with X-Shooter I. Unusual Chemistry in Halo Stars