Results 101 to 110 of about 805 (173)

Hot subdwarf formation: Confronting theory with observation

EPJ Web of Conferences, 2013
The formation of hot subdwarf stars is still unclear. Both single-star and binary scenarios have been proposed to explain the properties of these evolved stars situated at the extreme blue end of the horizontal branch. The observational evidence gathered
Geier S.
doaj   +1 more source

High-velocity streams in the Milky Way halo with the SDSS and GSC-II kinematic survey

EPJ Web of Conferences, 2012
We explore the stellar halo of the Milky Way to search for fossil signatures of past mergers, consisting of streams of particles torn from their progenitors during the process of hierarchical merging.
Spagna A., Smart R.L., Lattanzi M.G., Re Fiorentin P., Beers T.C., Curir A.   +5 more
doaj   +1 more source

He-rich Hot Subdwarf Stars Observed in Gaia DR3 and LAMOST DR7: Carbon and Nitrogen Abundances and Kinematics

The Astrophysical Journal Supplement Series
We conducted an analysis of the abundances of He, C, and N in 210 He-rich hot subdwarfs observed within both the Gaia Data Release 3 (DR3) and LAMOST DR7 data sets.
Yangping Luo, Péter Németh, Kun Wang, Yang Pan   +3 more
doaj   +1 more source

From synthetic SEDs to stellar origins: A deep learning model for physical parameter retrieval in hot subdwarf stars

Astronomy & Astrophysics
Aims. The formation mechanisms of spectrally diverse hot subdwarfs remain unclear. While existing mass distribution analyses suggest additional channels beyond helium white dwarf (He-WD) mergers contribute to He-rich subdwarf formation, these conclusions
Feng Mengqi, Lei Zhenxin, Kou Bokai, Dong Yangyang, Hu Ke, Xiao Huaping, Zhao Jingkun   +6 more
doaj   +1 more source

Hipparcos Subdwarfs And Globular Clusters: Towards Reliable Absolute Ages

The distance and age of the key globular cluster M92 are determined with Hipparcos field subdwarfs. [Fe/H] values for subdwarfs we re measured with the Coravel spectrometer.
Y. Lebreton, F. Pont, D.A. VandenBerg, C. Turon, M. Mayor, C. Charbonnel   +5 more
core  

The Solar Neighborhood. XLII. Parallax Results from the CTIOPI 0.9 m Program—Identifying New Nearby Subdwarfs Using Tangential Velocities and Locations on the H–R Diagram [PDF]

, 2017
Parallaxes, proper motions, and optical photometry are presented for 51 systems consisting of 37 cool subdwarf and 14 additional high proper motion systems. Thirty-seven systems have parallaxes reported for the first time, 15 of which have proper motions
Jao, Wei-Chun, Winters, Jennifer G., Subasavage, John P., Riedel, Adric R., Silverstein, Michele L., Ianna, Philip A., Henry, Todd J.   +6 more
core  

On the Capability of Oxidovanadium(IV) Derivatives to Act as All-Around Catalytic Promoters Since the Prebiotic World. [PDF]

Molecules, 2020
Campitelli P, Crucianelli M.
europepmc   +1 more source

Mergers via failed common envelope as a route toward intermediate-mass stripped stars

Astronomy & Astrophysics
Stripped stars are a common product of binary stellar systems, spanning a wide mass range from Wolf-Rayet stars to hot subdwarfs and helium white dwarfs.
Picco A., Marchant P., Pauli D., Sana H.
doaj   +1 more source

Kinematics Of Subdwarfs Based On Hipparcos Parallaxes And Proper Motions

Hipparcos parallaxes and proper motions were combined with radial velocities and metallicities from Carney et al. (1994). As a result a sample of 237 high-velocity stars was obtained having highly accurate space velocities and uniformly determined ...
B. Fuchs, R. Wielen, H. Jahreiß
core  

Accurate mass and radius determinations of a cool subdwarf in an eclipsing binary. [PDF]

Nat Astron, 2019
Rebassa-Mansergas A, Parsons SG, Dhillon VS, Ren J, Littlefair SP, Marsh TR, Torres S.   +6 more
europepmc   +1 more source