Search Publications

Global Parameters of 12 Totally Eclipsing W UMa Stars
DOI: 10.3847/1538-3881/ab4203 Bibcode: 2019AJ....158..186K

Popov, Velimir A.; Petrov, Nikola I.; Kjurkchieva, Diana P.

Photometric observations of 12 totally eclipsing W UMa binaries (NSVS 3325547, V646 Lac, V1320 Cas, V539 Dra, V816 Cep, NSVS 9045055, V1115 Cas, V902 Cep, V596 Peg, NSVS 1768818, V619 Peg, and NSVS 3198272) are presented. We found that the longer (in phase units) the flat eclipses are, the smaller the mass ratios (or the reciprocal values) are. Th…

2019 The Astronomical Journal
Gaia 21
TESS Habitable Zone Star Catalog
DOI: 10.3847/2041-8213/ab0e8d Bibcode: 2019ApJ...874L...8K

Stassun, K.; Kaltenegger, L.; Pepper, J. +1 more

We present the Transiting Exoplanet Survey Satellite (TESS) Habitable Zone Stars Catalog, a list of 1822 nearby stars with a TESS magnitude brighter than T = 12 and reliable distances from Gaia DR2, around which the NASA’s TESS mission can detect transiting planets, which receive Earth-like irradiation. For all those stars TESS is sensitive down t…

2019 The Astrophysical Journal
Gaia 21
The chemistry of stars in the bar of the Milky Way
DOI: 10.1051/0004-6361/201936779 Bibcode: 2019A&A...632A.121W

Schultheis, M.; Rojas-Arriagada, A.; Wegg, C. +1 more

We use a sample of 938 red clump giant stars located in the direction of the Galactic long bar to study the chemistry of Milky Way bar stars. Kinematically separating stars on bar orbits from stars with inner disc orbits, we find that stars on bar-like orbits are more metal rich with a mean iron abundance of ⟨[Fe/H]⟩ = +0.30 compared to ⟨[Fe/H]⟩ =…

2019 Astronomy and Astrophysics
Gaia 21
Quantifying the suppression of the (un)-obscured star formation in galaxy cluster cores at 0.2≲ z ≲0.9
DOI: 10.1093/mnras/sty3335 Bibcode: 2019MNRAS.485..586R

Rodighiero, G.; Valtchanov, I.; Franceschini, A. +21 more

We quantify the star formation (SF) in the inner cores (R/R200 ≤0.3) of 24 massive galaxy clusters at 0.2≲ z ≲0.9 observed by the Herschel Lensing Survey and the Cluster Lensing and Supernova survey with Hubble. These programmes, covering the rest-frame ultraviolet to far-infrared regimes, allow us to accurately characterize stellar mas…

2019 Monthly Notices of the Royal Astronomical Society
Herschel eHST 21
Masses, oxygen, and carbon abundances in CHEPS dwarf stars
DOI: 10.1051/0004-6361/201834138 Bibcode: 2019A&A...621A.112P

Jones, H. R. A.; Jenkins, J. S.; Pavlenko, Y. V. +3 more

Context. We report the results from the determination of stellar masses, carbon, and oxygen abundances in the atmospheres of 107 stars from the Calan-Hertfordshire Extrasolar Planet Search (CHEPS) programme. Our stars are drawn from a population with a significantly super-solar metallicity. At least 10 of these stars are known to host orbiting pla…

2019 Astronomy and Astrophysics
Gaia 21
The Unexpected Spectrum of the Innermost Ejecta of the Red Hypergiant VY CMa
DOI: 10.3847/2041-8213/ab11e5 Bibcode: 2019ApJ...874L..26H

Humphreys, Roberta M.; Jones, Terry J.; Gordon, Michael S. +6 more

Hubble Space Telescope/STIS spectra of the small clumps and filaments closest to the central star in VY CMa reveal that the very strong K I emission and TiO and VO molecular emission, long thought to form in a dusty circumstellar shell, actually originate in a few small clumps hundreds of au from the star. The K I lines are 10-20 times stronger in…

2019 The Astrophysical Journal
eHST 21
Extended main sequence turn-off originating from a broad range of stellar rotational velocities
DOI: 10.1038/s41550-018-0619-5 Bibcode: 2019NatAs...3...76L

Lim, Beomdu; Park, Byeong-Gon; Nazé, Yaël +3 more

Star clusters have long been considered to comprise a simple stellar population, but this paradigm is being challenged, since in addition to multiple populations in Galactic globular clusters1, a number of younger star clusters exhibit a significant colour spread at the main sequence turn-off2-9. A sequential evolution of mul…

2019 Nature Astronomy
Gaia 21
The backscattering ratio of comet 67P/Churyumov-Gerasimenko dust coma as seen by OSIRIS onboard Rosetta
DOI: 10.1093/mnras/sty2843 Bibcode: 2019MNRAS.482.2924B

Lara, L. M.; Bertaux, J. -L.; Lamy, P. +47 more

Remote sensing observations of dust particles ejected from comets provide important hints on the intimate nature of the materials composing these primitive objects. The measurement of dust coma backscattering ratio, BSR, defined as the ratio of the reflectance at phase angle 0° and 30°, helps tuning theoretical models aimed at solving the inverse …

2019 Monthly Notices of the Royal Astronomical Society
Rosetta 21
Multiwavelength Period-Luminosity and Period-Luminosity-Color Relations at Maximum Light for Mira Variables in the Magellanic Clouds
DOI: 10.3847/1538-4357/ab38c2 Bibcode: 2019ApJ...884...20B

Matsunaga, Noriyuki; de Grijs, Richard; Rejkuba, Marina +8 more

We present Period-Luminosity and Period-Luminosity-Color relations at maximum light for Mira variables in the Magellanic Clouds using time-series data from the Optical Gravitational Lensing Experiment (OGLE-III) and Gaia data release 2. The maximum-light relations exhibit a scatter typically up to ∼30% smaller than their mean-light counterparts. T…

2019 The Astrophysical Journal
Gaia 21
The Kitt Peak Electron Multiplying CCD demonstrator
DOI: 10.1093/mnras/stz497 Bibcode: 2019MNRAS.485.1412C

Kulkarni, S. R.; Duev, Dmitry A.; Riddle, Reed +10 more

The Kitt Peak Electron Multiplying CCD (EMCCD) demonstrator is a new instrument that has been developed for use at the Kitt Peak National Observatory's 84-inch telescope. The EMCCD enables single-band optical imaging in the Sloan g and r bands and Johnson UVRI filters. The EMCCD is chosen for its sub-electron effective read noise using large multi…

2019 Monthly Notices of the Royal Astronomical Society
Gaia 21