Related papers: Mass and Age determination of the LAMOST data with…

We examine the stellar populations of a sample of 98 redshift 4.5 Lyman alpha emitting galaxies using their broadband colors derived from deep photometry at the MMT. These galaxies were selected by narrowband excess from the Large Area…

The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) has obtained more than 23 million spectra, opening an unprecedented opportunity to study stellar physics, as well as the formation and evolution of our Milky Way. In…

We present a Mass-Luminosity Relation (MLR) for red dwarfs spanning a range of masses from 0.62 Msun to the end of the stellar main sequence at 0.08 Msun. The relation is based on 47 stars for which dynamical masses have been determined,…

We study 147 star clusters in the Large Magellanic Cloud (LMC) in order to determine their mean metallicities and ages, as well as the mean metallicities of 80 surrounding fields. We construct an age-metallicity relation (AMR) for the…

With the advent of dedicated photometric space missions, the ability to rapidly process huge catalogues of stars has become paramount. Bellinger and Angelou et al. (2016) recently introduced a new method based on machine learning for…

We probed stellar X-ray activity over a wide range of stellar parameters, using {\it Chandra} and LAMOST data. We measured the X-ray-to-bolometric luminosity ratio ($R_X = L_X/L_{\rm bol}$) for 484 main-sequence stars, and found a bimodal…

We introduce a galaxy cluster mass observable, $\mu_\star$, based on the stellar masses of cluster members, and we present results for the Dark Energy Survey (DES) Year 1 observations. Stellar masses are computed using a Bayesian Model…

Estimating stellar masses and radii is a challenge for most of the stars but their knowledge is critical for many different astrophysical fields. One of the most extended techniques for estimating these variables are the so-called empirical…

(Abridged) The red giant clump has been recently argued to be a reliable distance indicator for the galaxies in the Local Group. We re-address the problem of the systematic magnitude differences (DeltaM_I) between the local clump revealed…

We provide classifications for all 143 million non-repeat photometric objects in the Third Data Release of the Sloan Digital Sky Survey (SDSS) using decision trees trained on 477,068 objects with SDSS spectroscopic data. We demonstrate that…

Large pristine samples of red clump stars are highly sought after given that they are standard candles and give precise distances even at large distances. However, it is difficult to cleanly select red clumps stars because they can have the…

Stellar population models are commonly calculated using star clusters as calibrators for those evolutionary stages that depend on free parameters. However, discrepancies exist among different models, even if similar sets of calibration…

The massive stellar content, the OB associations and the star clusters in an HST field in M101 = NGC 5457 are investigated. A clustering algorithm yields 79 putative associations. Their size distribution is similar to that found in the…

Mass loss on the red giant branch (RGB) influences stellar evolution, properties of stellar populations, and Galactic chemical enrichment, yet remains poorly constrained observationally. Current models provide limited insight into how…

Red giants are an excellent tool for probing the history of star formation and subsequent metallicity evolution in the galaxies. The well-defined red giant branch (RGB) stars of the globular clusters can be used to determine their slopes…

We analyze the stellar populations of the Canis Major stellar over-density, using quantitative color-magnitude diagram (CMD) fitting techniques. The analysis is based on photometry obtained with the Wide Field Imager at the 2.2m telescope…

We demonstrate that highly accurate joint redshift-stellar mass probability distribution functions (PDFs) can be obtained using the Random Forest (RF) machine learning (ML) algorithm, even with few photometric bands available. As an…

We assemble the most complete and clean red supergiant (RSG) sample (2,121 targets) so far in the Small Magellanic Cloud (SMC) with 53 different bands of data to study the MLR of RSGs. In order to match the observed spectral energy…

We have studied the optical spectra of a sample of 31 O- and early B-type stars in the Small Magellanic Cloud, 21 of which are associated with the young massive cluster NGC 346. Stellar parameters are determined using an automated fitting…

Observations of 48 red-clump stars were obtained in the H band with the PIONIER instrument installed at the Very Large Telescope Interferometer. Limb-darkened angular diameters were measured by fitting radial intensity profile I(r) to…