相关论文: Featureless stars: Flux Calibration for Extremely …

We present a sample of 115 very low optical surface brightness, highly extended, HI-rich galaxies carefully selected from the ALFALFA survey that have similar optical absolute magnitudes, surface brightnesses, and radii to recently…

R-band surface photometry is presented for 171 late-type dwarf and irregular galaxies. For a subsample of 46 galaxies B-band photometry is presented as well. We present surface brightness profiles as well as isophotal and photometric…

We assembled a catalogue of bright, hot subdwarf and white dwarf stars extracted from a joint ultraviolet, optical, and infrared source list. The selection is secured using colour criteria that correlate well with effective temperatures…

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…

Improvements in the precision of the astrophysical flux scale are needed to answer fundamental scientific questions ranging from cosmology to stellar physics. The unexpected discovery that the expansion of the universe is accelerating was…

Hot DA white dwarfs have fully radiative pure hydrogen atmospheres that are the least complicated to model. Pulsationally stable, they are fully characterized by their effective temperature Teff, and surface gravity log g, which can be…

The apparent size of stars is a crucial benchmark for fundamental stellar properties such as effective temperatures, radii and surface gravities. While interferometric measurements of stellar angular diameters are the most direct method to…

We discuss the panchromatic properties of 99,088 galaxies selected from the SDSS Data Release 1 spectroscopic sample (a flux-limited sample for 1360 deg^2). These galaxies are positionally matched to sources detected by ROSAT, GALEX, 2MASS,…

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…

The u band magnitude is vital for determining stellar parameters and investigating specific astronomical objects. However, flux calibration in the u band for stars in the Galactic disk presents significant challenges. In this study, we…

We present spectrophotometric data from 0.4 to 4.2 microns for bright, northern sky, Be stars and several other types of massive stars. Our goal is to use these data with ongoing, high angular resolution, interferometric observations to…

We have selected an all--sky sample of 893 galaxies from the IRAS FSC--2, defined by a total (ADDSCAN) 12um flux limit of 0.22~Jy. Completeness is verified to 0.30~Jy, below which we have quantified the incompleteness down to 0.22~Jy for…

(abridged) We develop a tool for the automated spectral classification of OB stars according to their sub-types. We use the regular Random Forest (RF) algorithm, the Probabilistic RF (PRF), and we introduce the KDE-RF method which is a…

Extragalactic sources from the IRAS Faint Source Catalog (FSC) which have the optically faintest magnitudes (E > 18) were selected by spatial coincidence with a source in the FIRST radio survey, and 28 of these sources have been observed…

We are using the 2dF spectrograph to make a survey of all objects (`stars' and `galaxies') in a 12 sq.deg region towards the Fornax cluster. We have discovered a population of compact emission-line galaxies unresolved on photographic sky…

Context. The advent of the Extremely Large Telescope (ELT) will increase the collecting area by more than an order of magnitude compared to the individual Unit Telescopes of the Very Large Telescope (VLT). Fainter spectrophotometric…

We present the first volume-limited sample of spectroscopically confirmed hot subluminous stars out to 500 pc, defined using the accurate parallax measurements from the {\em Gaia} space mission data release 3 (DR3). The sample comprises a…

We present the characterization and definitive flux calibration of the Far-Infrared Field Integral Line Spectrometer (FIFI-LS) instrument on-board SOFIA. The work is based on measurements made in the laboratory with an internal calibrator…

We present high-resolution near-infrared spectra, obtained with the NIRSPEC spectrograph on the W. M. Keck II Telescope, of a collection of hot, massive stars within the central 25 arcseconds of the Galactic center. We have identified a…

Pan-STARRS1 has carried out a set of distinct synoptic imaging sky surveys including the $3\pi$ Steradian Survey and the Medium Deep Survey in 5 bands ($grizy_{P1}$). The mean 5$\sigma$ point source limiting sensitivities in the stacked…