Related papers: Leonessa: An Extremely Metal-poor Galaxy Undergoin…
Metallicity is a crucial tracer of galaxy evolution, providing insights into gas accretion, star formation, and feedback. At high redshift, these processes reveal how early galaxies assembled and enriched their interstellar medium. In this…
Our knowledge about the chemical evolution of the more luminous dwarf spheroidal (dSph) galaxies is constantly growing. However, little is known about the enrichment of the ultrafaint systems recently discovered in large numbers in large…
The warm ionized gas in low-mass, metal-poor starforming galaxies is chemically homogeneous despite the prevalence of large H II regions which contain hundreds of evolved massive stars, supernovae, and Wolf-Rayet stars with…
We investigate the star formation and chemical evolution in the early universe by considering the merging history of the Galaxy in the {\Lambda}CDM scenario according to the extended Press-Schechter theory. We give some possible constraints…
We study relations between stellar mass, star formation and gas-phase metallicity in a sample of 177,071 unique emission line galaxies from the SDSS-DR7, as well as in a sample of 43,767 star forming galaxies at z=0 from the cosmological…
It has been suggested that a class of chemically peculiar metal-poor stars called iron-rich metal-poor (IRMP) stars formed from molecular cores with metal contents dominated by thermonuclear supernova nucleosynthesis. If this interpretation…
We present demography of the dynamics and gas-mass fraction of 33 extremely metal-poor galaxies (EMPGs) with metallicities of $0.015-0.195~Z_\odot$ and low stellar masses of $10^4-10^8~M_\odot$ in the local universe. We conduct deep optical…
Even over relatively recent epochs, galaxies have evolved significantly in their location in the mass-metallicity plane, which must be telling us something about the latter stages of galaxy evolution. In this paper, we analyse data from the…
We present the stellar metallicities and multi-element abundances (C, Mg, Si, Ca, Ti, Cr, and Fe) of 15 massive (log $M/M_\odot=10.2-11.2$) quiescent galaxies at z=1-3, derived from ultradeep JWST-SUSPENSE spectra. Compared to quiescent…
We present results on the z~2.3 mass-metallicity relation (MZR) using early observations from the MOSFIRE Deep Evolution Field (MOSDEF) survey. We use an initial sample of 87 star-forming galaxies with spectroscopic coverage of H\beta,…
We present homogeneous abundance analysis of over 20 elements for 385 very metal-poor (VMP) stars based on the LAMOST survey and follow-up observations with the Subaru Telescope. It is the largest high-resolution VMP sample (including 363…
Physical properties of galaxies at z>7 are of interest for understanding both the early phases of star formation and the process of cosmic reionization. Chemical abundance measurements offer valuable information on the integrated star…
In this paper we analyze the kinematics, chemistry, and physical properties of a sample of the most metal-poor damped Lyman-alpha systems (DLAs), to uncover their links to modern-day galaxies. We present evidence that the DLA population as…
We present a search for galaxies in the local Universe with extremely low oxygen abundance, that is, more than 25 times lower than solar, which corresponds to 12 + log(O/H) < 7.3. To determine the oxygen abundance, we apply the direct Te…
We present 6.5-meter MMT and 3.5m APO spectrophotometry of 69 H II regions in 42 low-metallicity emission-line galaxies, selected from the Data Release 7 of the Sloan Digital Sky Survey to have mostly [O III]4959/Hbeta < 1 and [N…
The early chemical evolution of the Galaxy and the Universe is vital to our understanding of a host of astrophysical phenomena. Since the most metal-poor Galactic stars (with metallicities down to [Fe/H]\sim-5.5) are relics from the…
The goal of this study is to measure parameters of the integrated HI emission for twenty-two dwarf galaxies with oxygen abundance 12+log(O/H) in the range of 7.42 to 7.65, which are representatives of the eXtremely Metal-Deficient (XMD)…
We present MMT spectroscopic observations of HII regions in 42 low luminosity galaxies in the LVL. For 31 galaxies, we measured the temperature sensitive [O III] line at a strength of 4 sigma or greater, and thus determine direct oxygen…
Observations of evolution in the dust-to-metal ratio allow us to constrain the dominant dust processing mechanisms. In this work, we present a study of the dust-to-metal and dust-to-gas ratios in a sub-sample of ~500 DustPedia galaxies.…
Metal-poor stars provide the fossil record of Galactic chemical evolution and the nucleosynthesis processes that took place at the earliest times in the history of our Galaxy. From detailed abundance studies of low mass, extremely…