J0811+4730: the most metal-poor star-forming dwarf galaxy known

Abstract

We report the discovery of the most metal-poor dwarf star-forming galaxy (SFG) known to date, J0811+4730. This galaxy, at a redshift z=0.04444, has a Sloan Digital Sky Survey (SDSS) g-band absolute magnitude M_g = -15.41 mag. It was selected by inspecting the spectroscopic data base in the Data Release 13 (DR13) of the SDSS. LBT/MODS spectroscopic observations reveal its oxygen abundance to be 12 + log O/H = 6.98 +/- 0.02, the lowest ever observed for a SFG. J0811+4730 strongly deviates from the main-sequence defined by SFGs in the emission-line diagnostic diagrams and the metallicity - luminosity diagram. These differences are caused mainly by the extremely low oxygen abundance in J0811$+$4730, which is ~10 times lower than that in main-sequence SFGs with similar luminosities. By fitting the spectral energy distributions of the SDSS and LBT spectra, we derive a stellar mass of M* = 10^6.24 - 10^6.29 Msun (statistical uncertainties only), and we find that a considerable fraction of the galaxy stellar mass was formed during the most recent burst of star formation.

12 pages, 5 figures, accepted for publication in MNRAS

References in corpus (3)

• The Effects of Stellar Rotation. II. A Comprehensive Set of Starburst99 Models
• I Zw 18 revisited with HST/ACS and Cepheids: New Distance and Age
• Excitation properties of galaxies with the highest [OIII]/[OII] ratios: No evidence for massive escape of ionizing photons

Cited by in corpus (72)

• De Re Metallica: The cosmic chemical evolution of galaxies
• The chemical enrichment in the early Universe as probed by JWST via direct metallicity measurements at z~8
• JADES: Probing interstellar medium conditions at $z\sim 5.5-9.5$ with ultra-deep JWST/NIRSpec spectroscopy
• Lyman continuum leakage from low-mass galaxies with Mstar < 1.E8 Msun
• EMPRESS. V. Metallicity Diagnostics of Galaxies over 12+log(O/H)=~6.9-8.9 Established by a Local Galaxy Census: Preparing for JWST Spectroscopy
• The PHLEK Survey: A New Determination of the Primordial Helium Abundance
• Extremely metal-poor galaxies with HST/COS: laboratories for models of low-metallicity massive stars and high-redshift galaxies
• Extremely Metal-Poor Representatives Explored by the Subaru Survey (EMPRESS). I. A Successful Machine Learning Selection of Metal-Poor Galaxies and the Discovery of a Galaxy with M*<10^6 M_sun and 0.016 Z_sun
• An extremely metal poor star complex in the reionization era: Approaching Population III stars with JWST
• Census of the Local Universe (CLU) Narrow-Band Survey I: Galaxy Catalogs from Preliminary Fields
• New AGN diagnostic diagrams based on the [OIII]$\lambda 4363$ auroral line
• Low-redshift compact star-forming galaxies as analogues of high-redshift star-forming galaxies
• Early Results from GLASS-JWST. XXI: Rapid assembly of a galaxy at z=6.23 revealed by its C/O abundance
• J1234+3901: an extremely metal-deficient compact star-forming dwarf galaxy at redshift 0.133
• Low-redshift lowest-metallicity star-forming galaxies in the SDSS DR14
• EMPRESS. II. Highly Fe-Enriched Metal-poor Galaxies with $\sim 1.0$ (Fe/O)${}_{\odot }$ and $0.02$ (O/H)${}_{\odot }$ : Possible Traces of Super Massive ($>300M_{\odot }$) Stars in Early Galaxies
• The Leoncino Dwarf Galaxy: Exploring the Low-Metallicity End of the Luminosity-Metallicity and Mass-Metallcity Relations
• J2229+2725: an extremely low-metallicity dwarf compact star-forming galaxy with an exceptionally high [OIII]5007/[OII]3727 flux ratio of 53
• Large Binocular Telescope observations of new six compact star-forming galaxies with [NeV] 3426A emission
• Lyman alpha and Lyman continuum emission of MgII-selected star-forming galaxies
• Chemical and stellar properties of star-forming dwarf galaxies
• The Red Dead Redemption Survey of Circumgalactic Gas About Massive Galaxies. I. Mass and Metallicity of the Cool Phase
• Chemical abundances and radial velocities in the extremely metal-poor galaxy DDO 68
• Photometric identification and MMT spectroscopy of new extremely metal-poor galaxies: towards a better understanding of young stellar populations at low metallicity
• Evolutionary tracks, ejecta, and ionizing photons from intermediate-mass to very massive stars with PARSEC
• Properties of five z~0.3-0.4 confirmed LyC leakers: VLT/XShooter observations
• Void galaxies in the nearby Universe. I. Sample description
• XMP gas-rich dwarfs in nearby voids: results of BTA spectroscopy
• The impact of very massive stars on the chemical evolution of extremely metal-poor galaxies
• Lyman Continuum Escape Fraction from Low-mass Starbursts at z=1.3
• XMP gas-rich dwarfs in Nearby Voids: results of SALT spectroscopy
• On the use of Sulphur as a tracer for abundances in galaxies
• New insights on the nebular emission, ionizing radiation and low metallicity of Green Peas from advanced modelling
• Ly-alpha emission in low-redshift most metal-deficient compact star-forming galaxies
• LISA sources from young massive and open stellar clusters
• The Bimodal Absorption System Imaging Campaign (BASIC) I. A Dual Population of Low-metallicity Absorbers at z $<1$
• Gas-phase Fe/O and Fe/N abundances in Star-Forming Regions. Relations between nucleosynthesis, metallicity and dust
• The frequency of very young galaxies in the local Universe: I. A test for galaxy formation and cosmological models
• The Stellar Populations of HII galaxies: A tale of three bursts
• The frequency of very young galaxies in the local Universe: II. The view from SDSS spectra
• Optical spectroscopy of the extremely metal-deficient star-forming galaxy HSC J1631+4426: a test of the strong-line method
• Trading oxygen for iron I: the [O/Fe] -- specific star formation rate relation of galaxies
• Extremely strong CIV 1550 nebular emission in the extremely low-metallicity star-forming galaxy J2229+2725
• Investigating the physical properties of galaxies in the Epoch of Reionization with MIRI/JWST spectroscopy
• EMPRESS. XI. SDSS and JWST Search for Local and z~4-5 Extremely Metal-Poor Galaxies (EMPGs): Clustering and Chemical Properties of Local EMPGs
• Dancing in the void: hydrodynamical N-body simulations of the extremely metal poor galaxy DDO 68
• Mapping the ionized gas of the metal-poor HII galaxy PHL 293B with MEGARA
• An old stellar population or diffuse nebular continuum emission discovered in green pea galaxies
• Exploring Spatially-Resolved Metallicities, Dynamics and Outflows in Low-Mass Galaxies at $z\sim 7.6$
• Peekaboo: the extremely metal poor dwarf galaxy HIPASS J1131-31
• Hα Dots: Direct-Method Metal Abundances of Low-Luminosity Star-Forming Systems
• Hydrodynamics and Nucleosynthesis of Jet-Driven Supernovae II: Comparisons with Abundances of Extremely Metal-Poor Galaxies and Constraints on Supernova Progenitors
• J1046+4047: an extremely low-metallicity dwarf star-forming galaxy with O32 = 57
• EMPRESS. XII. Statistics on the Dynamics and Gas Mass Fraction of Extremely-Metal Poor Galaxies
• XMP gas-rich dwarfs in Nearby Voids: candidate selection
• Young stellar clumps in the interacting systems: Arp305
• Monitoring broad emission-line components in spectra of the two low-metallicity dwarf compact star-forming galaxies SBS 1420+540 and J1444+4840
• The Lyman Alpha Reference Sample IX: Revelations from deep surface photometry
• Properties of the Lowest Metallicity Galaxies Over the Redshift Range z = 0.2 to z = 1
• The properties and environment of very young galaxies in the local Universe
• An Unusual Transient in the Extremely Metal-Poor Galaxy SDSS J094332.35+332657.6 (Leoncino Dwarf)
• DDO68 C: the actual appearance of a ghost satellite dwarf through adaptive optics at the Large Binocular Telescope
• One of Everything: The Breakthrough Listen Exotica Catalog
• Leonessa: An Extremely Metal-poor Galaxy Undergoing Secular Chemical Evolution
• A new insight of AGC198691 (Leoncino) galaxy with MEGARA at the GTC
• MARTA: The connection between chemical enrichment, feedback, and dust in a Wolf-Rayet galaxy at z$\sim$2
• A comprehensive chemical abundance analysis of the extremely metal poor Leoncino Dwarf galaxy (AGC 198691)
• The heart of NGC 5253 as seen with MUSE-NFM: nitrogen enrichment through stellar chemical feedback at parsec scales
• When did the initial mass function become bottom-heavy?
• When Stars Mimic Monsters: Spectral Evidence for an $\eta$ Carinae-like Giant Eruption in SBS 0335$-$052 E
• Very gas-rich extremely metal-poor blue void dwarfs
• Nearby void dwarf galaxies: recent results, the ongoing project and prospects