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Related papers: Low-metallicity (sub-SMC) massive stars

200 papers

We present the mass-metallicity (MZ) and luminosity-metallicity (LZ) relations at z ~ 0.8 from ~1350 galaxies in the Deep Extragalactic Evolutionary Probe 2 (DEEP2) survey. We determine stellar masses by fitting the spectral energy…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 H. J. Zahid , L. J. Kewley , F. Bresolin

We utilize Sloan Digital Sky Survey imaging and spectroscopy of ~53,000 star-forming galaxies at z~0.1 to study the relation between stellar mass and gas-phase metallicity. We derive gas-phase oxygen abundances and stellar masses using new…

(Abridged) The knowledge of the number and of the physical nature of low-metallicity massive galaxies is crucial for the determination and interpretation of the mass-metallicity relation (MZR). Using VLT-ISAAC near-infrared (NIR)…

Astrophysics of Galaxies · Physics 2015-04-29 C. Maier , B. L. Ziegler , S. J. Lilly , T. Contini , E. Perez Montero , F. Lamareille , M. Bolzonella , E. Le Floc'h

The stellar metallicity and its gradient pose constraints to the formation and evolution of galaxies. This is a study of the metallicity gradient of the LMC, SMC and M33 galaxies derived from their asymptotic giant branch (AGB) stars. The…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Maria-Rosa L. Cioni

A metal-rich environment facilitates planet formation, making metal-rich stars the most favorable targets for surveys seeking to detect new exoplanets. Using this advantage to identify likely low-mass planet hosts, however, has been…

Solar and Stellar Astrophysics · Physics 2012-03-15 Barbara Rojas-Ayala , Kevin R. Covey , Philip S. Muirhead , James P. Lloyd

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…

Astrophysics of Galaxies · Physics 2015-05-30 Anna Frebel

Ultra-faint dwarf galaxies (UFDs, $M_* < 10^5 M_\odot$) offer unique insights into early chemical evolution in low-mass systems. However, interpreting their metallicity distribution functions (MDFs) has been challenging due to limited…

We present the results of a study utilising ultra-deep, rest-frame UV, spectroscopy to quantify the relationship between stellar mass and stellar metallicity for 681 star-forming galaxies at $2.5<z<5.0$ ($\langle z \rangle = 3.5 \pm 0.6$)…

Observations of long gamma-ray bursts (LGRBs) offer a unique opportunity for probing the cosmic star formation history, although whether or not LGRB rates are biased tracers of star formation rate history is highly debated. Based on an…

High Energy Astrophysical Phenomena · Physics 2013-07-16 Jing-Meng Hao , Ye-Fei Yuan

We study the Luminosity-Metallicity Relation and the Stellar Mass-Metallicity Relation by performing chemo-dynamical simulations in a cosmological scenario. Our results predict a tight linear correlation between oxygen chemical abundance…

Astrophysics · Physics 2007-05-23 Maria Emilia De Rossi , Patricia Beatriz Tissera , Cecilia Scannapieco

We study the mass-metallicity relation of galactic systems with stellar masses larger than 10^9 Mo in Lambda-CDM scenarios by using chemical hydrodynamical simulations. We find that this relation arises naturally as a consequence of the…

Astrophysics · Physics 2009-11-13 Patricia B. Tissera , Maria E. De Rossi , C. Scannapieco

Massive main-sequence stars have convective cores and radiative envelopes, but also sub-surface convection zones caused by partial ionisation. However, the convective properties depend on opacity and a star's metallicity. Non-rotating 1D…

Solar and Stellar Astrophysics · Physics 2024-11-21 Dominic M. Bowman , Pieterjan Van Daele , Mathias Michielsen , Timothy Van Reeth

Based on a carefully constructed sample of dwarf stars, a new optical-near infrared photometric calibration to estimate the metallicity of late-type K and early-to-mid-type M dwarfs is presented. The calibration sample has two parts; the…

Solar and Stellar Astrophysics · Physics 2015-06-24 Neda Hejazi , Michael M. De Robertis , Peter C. Dawson

Using a cosmological hydrodynamical simulation of a galaxy of similar mass to the Large Magellanic Cloud (LMC), we examine the predicted characteristics of its lowest metallicity populations. In particular, we emphasise the spatial…

Astrophysics of Galaxies · Physics 2015-06-16 Chris B. Brook , Maider S. Miranda , Brad. K. Gibson , Kate Pilkington , Greg S. Stinson

Early B-type stars ($M_i=8-15$ M$_\odot$) are frequently in multiple systems, as evidenced by spectroscopic campaigns in the Milky Way (MW) and the Large Magellanic Cloud (LMC). Previous studies have shown no strong metallicity dependence…

We have derived high spatial resolution metallicity maps covering $\sim$42 deg$^2$ across the Small Magellanic Cloud (SMC) in an attempt to understand its metallicity distribution and gradients up to a radius of $\sim$ 4$^{\circ}$. Using…

The MEarth Project is a photometric survey systematically searching the smallest stars nearest to the Sun for transiting rocky planets. Since 2008, MEarth has taken approximately two million images of 1844 stars suspected to be mid-to-late…

Solar and Stellar Astrophysics · Physics 2016-03-09 Jason A Dittmann , Jonathan M Irwin , David Charbonneau , Elisabeth R Newton

Young populations at Z<Zo are being examined to understand the role of metallicity in the first phases of stellar evolution. For the analysis it is necessary to assign mass and age to Pre--Main Sequence (PMS) stars. While it is well known…

Astrophysics · Physics 2009-11-13 Di Criscienzo , P. Ventura , F. D'Antona

The chemical abundances of very metal-poor stars provide important constraints on the nucleosynthesis of the first generation of stars and early chemical evolution of the Galaxy. We have obtained high-resolution spectra with the Subaru…

We examine the metallicity distribution of the Galactic thick disk using F, G, and K dwarf stars selected from the Sloan Digital Sky Survey, Data Release 8. Using the large sample of dwarf stars with proper motions and spectroscopically…

Astrophysics of Galaxies · Physics 2012-11-29 Kenneth Carrell , Yuqin Chen , Gang Zhao