Results 71 to 80 of about 199 (140)

Classification of Metal-Deficient Dwarfs in the Vilnius Photometric System

Open Astronomy, 2003
Methods used for the quantitative classification of metal-deficient stars in the Vilnius photometric system are reviewed. We present a new calibration of absolute magnitudes for dwarfs and subdwarfs, based on Hipparcos parallaxes.
Lazauskaitė R., Bartkevičius A., Bartašiūtė S.   +2 more
doaj   +1 more source

The massive hot subdwarf binary LAMOST J065816.72+094343.1

Astronomy & Astrophysics
Context. Massive short-period binaries involving hot subdwarf stars (sdO/Bs) are rare but very relevant to constraining pathways for binary star evolution.
Mattig F., Barlow B. N., Liu D., Dorsch M., Geier S., Pritzkuleit M., Dawson H., Wang B., Schaffenroth V., Kupfer T., Derbyshire C., Barocci-Faul S.   +11 more
doaj   +1 more source

BlackGEM observations of compact pulsating stars

Astronomy & Astrophysics
Context. While space-based telescopes offer unparalleled precision for asteroseismology, ground-based observations remain crucial for identifying compact pulsator candidates and enabling their pulsational study through multi-colour photometry.
Ranaivomanana P., Johnston C., Uzundag M., Groot P. J., Kupfer T., Bloemen S., Vreeswijk P. M., van Roestel J. C. J., Pieterse D. L. A., Paice J., Kosakowski A., Ramsay G., Aerts C.   +12 more
doaj   +1 more source

The evolution of a hot subdwarf: observations of the pulsating subdwarf B star Feige~48

, 2003
Since pulsating subdwarf B (sdBV or EC14026) stars were first discovered (Kilkenny et al, 1997), observational efforts have tried to realize their potential for constraining the interior physics of extreme horizontal branch (EHB) stars. Difficulties encountered along the way include uncertain mode identifications and a lack of stable pulsation mode ...
Reed, M. D., Kawaler, S. D., teams., the Whole Earth Telescope XCov 17 / 21 / 23   +2 more
openaire   +2 more sources

Observing orbital decay in the ultracompact hot subdwarf binary system ZTFJ213056.71+442046.5

Astronomy & Astrophysics
Context. Ultracompact Galactic binary systems emit low-frequency gravitational waves in the millihertz regime. The emission of gravitational waves causes these systems to lose angular momentum, which is detectable by observing the decay of the orbital ...
Teckenburg Paul, Kupfer Thomas, Brown Alex J., Roth Martin M., Ben Daya Fatma, Knoche Jörg, Lali Ananthu K., Vješnica Stella, Roje Paško, Kretlow Mike, Cikota Stefan   +10 more
doaj   +1 more source

Toward 3D orbits of wide sdO/B binaries

Astronomy & Astrophysics
Hot subdwarf stars (sdO/Bs) are widely considered to be products of binary evolution. A significant fraction of them is found in long-period or wide binaries (P > 500 d) with main-sequence (MS) companions, likely resulting from a stable mass-transfer ...
Deshmukh K., Geier S., Sana H., Dawson H., Dorsch M., Frost A. J., Heber U., Kupfer T., Picco A., Vučković M.   +9 more
doaj   +1 more source

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

Evidence for neutron capture in heavy-metal hot subdwarfs

Astronomy & Astrophysics
Context. Most hot subdwarfs (sdO/B) are low-mass core-helium-burning stars formed through binary interaction. A subgroup of intermediate He-rich sdOBs shows extreme heavy metal (Z > 30) enrichments exceeding 104 times solar, particularly in Zr or Pb ...
Dorsch M., Jeffery C. S., Deprince J., Dougan D. J., Beauraind S., Dupuis H., Battich T., Quinet P., Heber U., Scott L. J. A., Geier S.   +10 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

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