中文
相关论文

相关论文: Star Formation in Ultrafaint Dwarfs: Continuous or…

200 篇论文

We use the self-consistent model technique developed by Mart\'in-Manj\'on et al. (2008) that combines the chemical evolution with stellar population synthesis and photo-ionization codes, to study the star formation scenarios capable of…

宇宙学与河外天体物理 · 物理学 2015-06-03 M. L. Martín-Manjón , M. Mollá , A. I. Díaz , R. Terlevich

We present a large sample of fully self-consistent hydrodynamical Nbody/Tree-SPH simulations of isolated dwarf spheroidal galaxies (dSphs). It has enabled us to identify the key physical parameters and mechanisms at the origin of the…

星系天体物理 · 物理学 2015-05-13 Y. Revaz , P. Jablonka , T. Sawala , V. Hill , B. Letarte , M. Irwin , G. Battaglia , A. Helmi , M. D. Shetrone , E. Tolstoy , K. A. Venn

We extend our previous work on the age-chemical abundance structure of the Galactic outer disc to the inner disc (4 < r < 8 kpc) based on the SDSS/APOGEE survey. Different from the outer disc, the inner disc stars exhibit a clear bimodal…

We propose a simple analytic model to understand when star formation is time-steady versus bursty in galaxies. Recent models explain the observed Kennicutt-Schmidt relation between star formation rate and gas surface densities in galaxies…

星系天体物理 · 物理学 2017-12-06 C. -A. Faucher-Giguere

We investigate the burstiness of star formation histories (SFHs) of galaxies at $0.4<z<1$ by using the ratio of star formation rates (SFRs) measured from H$\beta$ and FUV (1500 \AA) (H$\beta$--to--FUV ratio). Our sample contains 164…

With the launch of JWST and the upcoming installation of extremely large telescopes, the first galaxies in our Universe will finally be revealed. Their light will be dominated by massive stars, which peak in in the ultra-violet (UV) part of…

星系天体物理 · 物理学 2020-05-15 Jorick S. Vink

Observations suggest that star formation occurs in only one or two crossing times for a range of scales spanning a factor of 1000. These observations include (1) measurements of embedded cluster ages in comparison with the cloud core…

天体物理学 · 物理学 2009-10-31 Bruce G. Elmegreen

In the FirstLight project, we have used ~300 cosmological, zoom-in simulations to determine the star-formation histories of distinct first galaxies with stellar masses between Ms=10^6 and 3 x 10^9 Msun during cosmic dawn (z=5-15). The…

星系天体物理 · 物理学 2018-08-20 Daniel Ceverino , Ralf Klessen , Simon Glover

We use SEDz* -- a code designed to chart star formation histories (SFHs) of 6<z<12 galaxies -- to analyze the SEDs of 894 galaxies with deep JWST/NIRCam imaging by JADES in the GOODS-S field. We show how SEDz* matches observed SEDs using…

Milky Way-mass galaxies in the FIRE-2 simulations demonstrate two main modes of star formation. At high redshifts star formation occurs in a series of short and intense bursts, while at low redshifts star formation proceeds at a steady rate…

We present NLTE abundances and atmospheric parameters for three metal-poor stars ([Fe/H]<-2) in Coma Berenices ultra-faint dwarf galaxy (UFD). The derived results are based on new photometric observations obtained with the 2.5-m telescope…

太阳与恒星天体物理 · 物理学 2018-12-05 Tatyana Sitnova , Lyudmila Mashonkina , Andrey Tatarnikov , Olga Voziakova , Marina Burlak , Yuriy Pakhomov

We derive and analyse the star formation histories of 393 intermediate-redshift (0.1 $\leq$ z $\leq$ 0.9) galaxies with stellar masses between $\sim$10$^{8}$ - 10$^{12}$ M$_{\odot}$. We probe a cosmic time of approximately 6 Gyr and a range…

The redshift range z=4-6 marks a transition phase between primordial and mature galaxy formation in which galaxies considerably increase their stellar mass, metallicity, and dust content. The study of galaxies in this redshift range is…

星系天体物理 · 物理学 2019-11-06 Andreas L. Faisst , Peter L. Capak , Najmeh Emami , Sandro Tacchella , Kirsten L. Larson

We present different chemical evolution models for the ultrafaint dwarf galaxy Bootes I. We either assume that the galaxy accretes its mass through smooth infall of gas of primordial chemical composition (classical models) or adopt mass…

星系天体物理 · 物理学 2015-06-23 Donatella Romano , Michele Bellazzini , Else Starkenburg , Ryan Leaman

We study in detail the properties of the stellar populations of 111 massive ($\log(M_{\star}/\mathrm{M}_\odot) \ge 10)$ dusty (FIR-selected) starburst ($SFR/SFR_\mathrm{MS}>2$) galaxies at $0.7<z<1.2$. For that purpose, we use…

Star formation histories (SFHs) are essential for understanding galaxy formation and evolution. We present the mean SFHs of 148 dwarf lenticular galaxies (dS0s) derived from the Sloan Digital Sky Survey (SDSS) spectra. These SFHs reveal two…

星系天体物理 · 物理学 2024-03-29 Hong Bae Ann , Mira Seo

We investigate the star formation histories (SFHs) of high redshift (3 <~ z <~ 5) star-forming galaxies selected based on their rest-frame ultraviolet (UV) colors in the CANDELS/GOODS-S field. By comparing the results from the…

Ultra diffuse galaxies are a population of extended galaxies but with relatively low luminosities. The origin of these objects remains unclear, largely due to the observational challenges of the low surface brightness Universe. We present…

New observations indicate that ultrafaint dwarf galaxies (UFD) -- the least luminous systems bound by dark matter halos (<10^5 Lsun) -- may have formed before reionization. The extrapolated virial masses today are uncertain with estimates…

星系天体物理 · 物理学 2015-07-15 Joss Bland-Hawthorn , Ralph Sutherland , David Webster