Related papers: SkyMapper stellar parameters for Galactic Archaeol…
The Stellar Abundances and Galactic Evolution Survey (SAGES) of the northern sky is a specifically-designed multi-band photometric survey aiming to provide reliable stellar parameters with accuracy comparable to those from low-resolution…
Because of the recent technological advances, the key technologies needed for precision space optical astrometry are now in hand. The Microarcsecond Astrometry Probe (MAP) mission concept is designed to find 1 Earth mass planets at 1AU…
Stellar spectral classification is a fundamental tool of modern astronomy, providing insight into physical characteristics such as effective temperature, surface gravity, and metallicity. Accurate and fast spectral typing is an integral…
We analysed red giant branch stars in 16 Galactic globular clusters, computing their atmospheric parameters both from the photometry and from excitation and ionisation balances. The spectroscopic parameters are lower than the photometric…
We present improved methods for using stars found in astronomical exposures to calibrate both star and galaxy colors as well as to adjust the instrument flat field. By developing a spectroscopic model for the SDSS stellar locus in…
Photometric light curves suffer from fundamental degeneracies that limit surface information recovery. We demonstrate that astrometry enables access to complementary information through photocentre variations induced by rotating surface…
We present the Cosmic Evolution Early Release Science Survey (CEERS) catalog, including space-based photometry, photometric redshifts, and physical parameters for more than 80,000 galaxies. The imaging used for this catalog comes from the…
We present chemical abundances for 21 elements (from Li to Eu) in 150 metal-poor Galactic stars spanning $-$4.1 $<$ [Fe/H] $<$ $-$2.1. The targets were selected from the SkyMapper survey and include 90 objects with [Fe/H] $\le$ $-$3 of…
Photometric surveys at optical, ultraviolet, and infrared wavelengths provide ever growing datasets as major surveys proceed. Colour-colour diagrams are useful tools to identify classes of stars and to provide large samples. Combining all…
Getting spectra at good signal-to-noise ratios takes orders of magnitudes more time than photometric observations. Building on the technique developed for photometric redshift estimation of galaxies, we develop and demonstrate a…
Reliable estimation of stellar surface gravity (log $g$) for a large sample is crucial for evaluating stellar evolution models and understanding galactic structure; However, it is not easy to accomplish due to the difficulty in gathering a…
We report the discovery of stars that show spectra very close to the black-body radiation. We found 17 such stars out of 798,593 stars in the Sloan Digital Sky Survey (SDSS) spectroscopic data archives. We discuss the value of these stars…
Weak lensing of galaxies by large scale structure can potentially measure cosmological quantities as accurately as the cosmic microwave background (CMB). However, the relation between observables and fundamental parameters is more complex…
We present a recalibration of the Sloan Digital Sky Survey (SDSS) photometry with new flat fields and zero points derived from Pan-STARRS1 (PS1). Using PSF photometry of 60 million stars with $16 < r < 20$, we derive a model of amplifier…
Current and future weak lensing surveys will rely on photometrically estimated redshifts of very large numbers of galaxies. In this paper, we address several different aspects of the demanding photo-z performance that will be required for…
Photometry of galaxies has typically focused on small, faint systems due to their interest for cosmological studies. Large angular size galaxies, on the other hand, offer a more detailed view into the properties of galaxies, but bring a…
Symbiotic stars are binaries in which a cool and evolved star of luminosity class I-III accretes onto a smaller companion. However, direct accretion signatures like disc flickering and boundary layer X-rays are typically outshone or…
We present a photometric method for identifying stars, galaxies and quasars in multi-color surveys and estimating multi-color redshifts for the extragalactic objects. We use a library of >65000 color templates for comparison with observed…
The estimation of stellar atmospheric parameters for large-scale samples, particularly metal-poor stars, is a cornerstone of Galactic archaeology. In this work, we optimized a photometric filter design tailored to measuring stellar…
[Abridged] Several large scale photometric and spectroscopic surveys are being undertaken to provide a more detailed picture of the Milky Way. Given the necessity of generalisation in the determination of, e.g., stellar parameters when tens…