Results 31 to 40 of about 199 (140)

Detection of stellar oscillations in HWVir

Open Astronomy, 2016
We present our analysis of K2 observations of the binary system, HWVir. We processed the raw Kepler data and used Fourier analysis to search for periodic signals that could be associated with pulsations.
Baran Andrzej S., Østensen Roy H., Telting John H.   +2 more
doaj   +1 more source

Rotation in sdB stars as revealed by stellar oscillations

Open Astronomy, 2018
An interesting opportunity offered by the detection of stellar oscillations is the possibility to infer the internal rotation rate of a star through the so-called rotational splittings. Such seismic measurements remained rather scarce for hot B subdwarf (
Charpinet Stephane, Giammichele Noemi, Zong Weikai, Van Grootel Valérie, Brassard Pierre, Fontaine Gilles   +5 more
doaj   +1 more source

A 500 pc volume-limited sample of hot subluminous stars

Astronomy & Astrophysics
We present a quantitative spectroscopic and kinematic analysis of a volume-complete sample of hot subluminous stars within 500 pc of the Sun, assembled using accurate parallax measurements from the Gaia space mission Data Release 3 (DR3).
Dawson H., Dorsch M., Geier S., Munday J., Pritzkuleit M., Heber U., Mattig F., Benitez-Palacios D., Vučković M., Pelisoli I., Deshmukh K., Bhat A., Kufleitner L., Uzundag M., Schaffenroth V., Reindl N., Culpan R., Raddi R., Antunes Amaral L., Istrate A. G., Justham S., Østensen R. H., Telting J. H., Steinmetz T., Rodríguez-Segovia N., Fernandez-Schlosser P., Durán-Reyes A., Arancibia-Rojas E., Latour M., Jones G. T., O’Brien M., Sahu S., Elms A.   +32 more
doaj   +1 more source

A small survey of UV-bright stars around the northern ecliptic pole: seeking new p-mode sdB variables for the TESS mission

Open Astronomy, 2019
Starting in 2019, the TESS mission will monitor the northern ecliptic pole for 1 year. Data will be collected at 30-minute and 2-minute cadences, and only a limited amount of slots will be reserved for targets requiring a 20- second cadence.
Prins Saskia, Telting John, Østensen Roy   +2 more
doaj   +1 more source

COOL SUBDWARF INVESTIGATIONS. I. NEW THOUGHTS ON THE SPECTRAL TYPES OF K AND M SUBDWARFS [PDF]

The Astronomical Journal, 2008
Using new spectra of 88 K and M-type subdwarfs, we consider novel methods for assigning their spectral types and take steps toward developing a comprehensive spectral sequence for subdwarf types K3.0 to M6.0. The types are assigned based on the overall morphology of spectra covering 6000Åto 9000Å.
Jao, Wei-Chun, Henry, Todd J., Beaulieu, Thomas D., Subasavage, John P.   +3 more
openaire   +2 more sources

Discovery of the first outbursting hot subdwarf binary: ZTF J0007+4804

Astronomy & Astrophysics
Context. Hot subdwarf binaries with white dwarf companions with orbital periods of less than two hours are progenitor candidates for massive single white dwarfs as well as a variety of thermonuclear explosions. Aims.
Stringer E., Kupfer T., Deshmukh K., Maccarone T., Jackson I., Kosakowski A., Bradshaw C. W., Brown A., Dorsch M., Picco A., Dhillon V. S., Poshyachinda S., Awiphan S.   +12 more
doaj   +1 more source

Spectral energy distributions and colours of hot subluminous stars

Open Astronomy, 2018
Photometric surveys at optical, ultraviolet, and infrared wavelengths provide ever-growing datasets as major surveys proceed. Colour-colour diagrams are useful tools to identify classes of star and provide large samples.
Heber Ulrich, Irrgang Andreas, Schaffenroth Johannes   +2 more
doaj   +1 more source

The EC14026 Stars — Pulsating Hot Subdwarfs [PDF]

Symposium - International Astronomical Union, 1998
The Edinburgh-Cape Blue Object Survey (Stobie et al. 1997a) is a southern hemisphere survey to discover hot, blue stellar objects brighter than B=18 at galactic latitudes more than 30° from the galactic plane. The main categories of object detected are hot subdwarfs, white dwarfs, blue horizontal branch stars, apparently normal B stars, cataclysmic ...
C. Koen, D. O'Donoghue, D. Kilkenny, R.S. Stobie   +3 more
openaire   +1 more source

Halo stars harbour few wide ultracool companions

Astronomy & Astrophysics
Aims. Our goal is to provide a wide ultracool companion frequency for metal-poor halo stars for the first time. Methods. We selected nearby halo stars with spectroscopically determined high proper motions and metallicities.
Zhang J.-Y., Lodieu N., Martín E. L.
doaj   +1 more source

Wide B-type hot subdwarf binaries

Astronomy & Astrophysics
Context. Long-period binary systems containing a B-type hot subdwarf (sdB) and a main sequence (MS) companion are thought to originate from binary interactions involving stable mass transfer from the red giant, which is the progenitor of the sdB, to the ...
Molina Francisco, Vos Joris, Bobrick Alexey, Vučković Maja   +3 more
doaj   +1 more source