相关论文: Effects of Metallicity on High Mass X-ray Binary F…
Dust is important for star formation because it is the crucial component that couples gas to stellar radiation fields, allowing radiation feedback to influence gas fragmentation and thus the stellar initial mass function (IMF). Variations…
We introduce a method for obtaining the X-ray luminosity function (XLF) and the binary-period distribution of populations of high-mass X-ray binaries (HMXBs) in the stellar fields (i.e. outside globular clusters) of normal galaxies. We…
Long-Duration Gamma-Ray Bursts (GRBs) are powerful probes of the Universe star formation history, but correlation between the two depends on the highly debated presence/strength of a metallicity bias. To investigate this correlation, we use…
We use a sample of 43,690 galaxies selected from the Sloan Digital Sky Survey Data Release 4 to study the systematic effects of specific star formation rate (SSFR) and galaxy size (as measured by the half light radius, r_h) on the…
The first population of X-ray binaries (XRBs) is expected to affect the thermal and ionization states of the gas in the early Universe. Although these X-ray sources are predicted to have important implications for high-redshift observable…
Recent results have suggested that the well known mass-metallicity relation has a strong dependence on the star formation rate, to the extent that a three dimensional `fundamental metallicity relation' exists which links the three…
Recent studies have found higher galaxy metallicities in richer environments. It is not yet clear, however, whether metallicity-environment dependencies are merely an indirect consequence of environmentally dependent formation histories, or…
We obtained high resolution ELODIE and CORALIE spectra for both components of 20 wide visual binaries composed of an F-, G- or K-dwarf primary and an M-dwarf secondary. We analyse the well understood spectra of the primaries to determine…
We have studied high mass X-ray binary (HMXB) populations within two low-metallicity, starburst galaxies, Haro 11 and VV 114. These galaxies serve as analogs to high-redshift (z>2) Lyman break galaxies, and within the larger sample of Lyman…
We present a study of the mass-metallicity relation (MZR) of 51 dwarf galaxies ($M_\star\approx 10^{6.5} - 10^{9.5}~M_\odot$) at $z = 2-3$ from the Abell 2744 and SMACS J0723-3732 galaxy cluster fields. These dwarf galaxies are identified…
Emission from X-ray binaries (XRBs) is a major component of the total X-ray luminosity of normal galaxies, so X-ray studies of high redshift galaxies allow us to probe the formation and evolution of X-ray binaries on very long timescales.…
The use of extremely metal-deficient dwarf galaxies (XMDs) as nearby analogs for high-redshift protogalaxies is generating renewed interest due to recent JWST observations studying these protogalaxies. However, the existence of a population…
We present a systematic study of the metallicity variations within the collisional ring galaxy NGC 922 based on long-slit optical spectroscopic observations. We find a metallicity difference between star-forming regions in the bulge and the…
Using results of Chandra observations of old stellar systems in eleven nearby galaxies of various morphological types and the census of LMXBs in the Milky Way, we study the population of low mass X-ray binaries and their relation to the…
There is now strong evidence that Long-duration Gamma-Ray Bursts (LGRBs) are preferentially formed in low-metallicity environments. However, the magnitude of this effect, and its functional dependence on metallicity have not been well…
Knowledge of stellar atmospheric parameters ($T_{\rm eff}$, $\log{g}$, [Fe/H]) of M dwarfs can be used to constrain both theoretical stellar models and Galactic chemical evolutionary models, and guide exoplanet searches, but their…
We derive a sample of 114 Baldwin-Phillips-Terlevich diagram - star formation (BPT-SF) and Wide-field infrared Survey Exploer - low star formation rate (WISE-LSFR) early-type galaxies (ETGs) by utilizing the criterion W2-W3$<2.5$ (where W2…
The high mass X-ray binaries (HMXBs) provide an exciting framework to investigate the evolution of massive stars and the processes behind binary evolution. HMXBs have shown to be good tracers of recent star formation in galaxies and might…
The microlensing surveys, such as OGLE or MACHO, have led to the discovery of thousands of RR Lyrae stars in the Galactic Bulge and in the Magellanic Clouds, allowing for detailed investigation of these stars, specially the still mysterious…
We demonstrate that failure to properly account for stellar evolution can bias results in determinations of the spatial morphology of Galactic bulge stars, focusing on the question of whether or not the X-shape is more pronounced among the…