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Low-resolution near-infrared spectroscopic signatures of unresolved ultracool companions to M dwarfs
(2017-06-01)
We develop a method to identify the spectroscopic signature of unresolved L-dwarf ultracool companions, which compares the spectra of candidates and their associated control stars using spectral ratio differences and ...
2MASS 0213+3648 C: : A wide T3 benchmark companion to an an active, old M dwarf binary
(2017-05-01)
We present the discovery of a 360 AU separation T3 companion to the tight (3.1 AU) M4.5+M6.5 binary 2MASS J02132062+3648506. This companion was identified using Pan-STARRS1 data and, despite its relative proximity to the ...
Sc and neutron-capture abundances in Galactic low- and high-alpha field halo stars
(2017-05-01)
We determine relative abundance ratios for the neutron-capture elements Zr, La, Ce, Nd and Eu for a sample of 27 Galactic dwarf stars with −1.5 < [Fe/H] < −0.8. We also measure the iron-peak element Sc. These stars separate ...
Characterization of the VVV Survey RR Lyrae Population across the Southern Galactic Plane
(2017-03-27)
Deep near-IR images from the VISTA Variables in the Vía Láctea (VVV) Survey were used to search for RR Lyrae stars in the Southern Galactic plane. A sizable sample of 404 RR Lyrae of type ab stars was identified across a ...
Parallaxes and Infrared Photometry of three Y0 dwarfs
(2017-03-24)
We have followed up the three Y0 dwarfs WISEPA J041022.71+150248.5, WISEPA J173835.53+273258.9 and WISEPC J205628.90+145953.3 using the UKIRT/WFCAM telescope/instruments. We find parallaxes that are more consistent and ...
FSR 1716: A new Milky Way Globular Cluster confirmed using VVV RR Lyrae stars
(2017-03-24)
We use deep multi-epoch near-IR images of the VISTA Variables in the V\'ia L\'actea (VVV) Survey to search for RR Lyrae stars towards the Southern Galactic plane. Here we report the discovery of a group of RR Lyrae stars ...
A population of eruptive variable protostars in VVV
(2017-03-01)
We present the discovery of 816 high amplitude infrared variable stars (Delta Ks >1 mag) in 119 deg^2 of the Galactic midplane covered by the Vista Variables in the Via Lactea (VVV) survey. Almost all are new discoveries ...
Infrared spectroscopy of eruptive variable protostars from VVV
(2017-03-01)
In a companion work (Paper I) we detected a large population of highly variable Young Stellar Objects (YSOs) in the Vista Variables in the Via Lactea (VVV) survey, typically with class I or flat spectrum spectral energy ...
Production Uncertainties of p-Nuclei in the γ-Process in Massive Stars Using a Monte Carlo Approach
(2017-02-28)
Proton-rich nuclei, the so-called p-nuclei, are made in photodisintegration processes in outer shells of massive stars in the course of the final supernova explosion. Nuclear uncertainties in the production of these nuclei ...
Impacts of nuclear-physics uncertainty in stellar temperatures on the s-process nucleosynthesis
(The Physical Society of Japan, 2017-02-28)
We evaluated the uncertainty relevant to s-process nucleosynthesis using a Monte-Carlo centred approach. We are based on a realistic and general prescription of temperature dependent uncertainty for the reactions. We ...