Results 71 to 80 of about 7,790 (232)

Mass Distribution for Single-lined Hot Subdwarf Stars in LAMOST

The Astrophysical Journal, 2023
Masses for 664 single-lined hot subdwarf stars identified in LAMOST were calculated by comparing synthetic fluxes from spectral energy distribution with observed fluxes from a Virtual Observatory service.
Zhenxin Lei, Ruijie He, Péter Németh, Xuan Zou, Huaping Xiao, Yong Yang, Jingkun Zhao   +6 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

BV CCD Photometry of M71: Distance and Age [PDF]

Journal of Astronomy and Space Sciences, 2004
We present BV CCD photometry of metal-rich globular cluster M71. Based on our color-magnitude diagram (CMD), we derive the distance to M71 using a sample of Hipparcos subdwarfs of similar metallicity. Our distance modulus is (m-M)V=13.46(± 0.17).
Hong-Suh Yim, Mun-Suk Chun, Yong-Ik Byun, Young-Jong Sohn   +3 more
doaj   +1 more source

The Unseen Population of F to K-type Companions to Hot Subdwarf Stars

, 2012
We present a method to select hot subdwarf stars with A to M-type companions using photometric selection criteria. We cover a wide range in wavelength by combining GALEX ultraviolet data, optical photometry from the SDSS and the Carlsberg Meridian ...
Abazajian, Allard, Aungwerojwit, Aznar Cuadrado, Aznar Cuadrado, B. T. Gänsicke, Ballouz, Bertone, Blanchette, Brown, Budavári, C. M. Copperwheat, Carpenter, Castellani, Castelli, Clausen, Copperwheat, D'Cruz, D. Steeghs, de Jong, Dobrzycka, Dorman, Dye, E. Breedt, Edelmann, Fekel, Ferguson, Fitzpatrick, Friedrich, Geier, Geier, Girardi, Girven, Green, Green, Green, Gänsicke, Han, Heber, Heber, Heber, Heber, Heber, Heber, Howarth, Humason, Iben, J. Girven, Jeffery, Jurić, Kilkenny, Koester, Li, Lisker, Marsh, Martin, Maxted, Maxted, Mengel, Michaud, Moni Bidin, Morales-Rueda, Morrissey, Napiwotzki, Napiwotzki, O'Toole, P. Longa-Peña, Papoular, Penning, Pickles, Politano, Rebassa-Mansergas, Reed, Ringwald, Ritter, S. Pyrzas, Saffer, Saffer, Saio, Schlegel, Skrutskie, Stark, Stark, Stroeer, Szkody, Szkody, T. R. Marsh, Thejll, Tillich, Tutukov, U. Heber, Ulla, Vennes, Viton, Wade, Wade, Webbink, Williams, Østensen   +98 more
core   +1 more source

A new class of pulsating hot subdwarfs [PDF]

, 2019
Using high-cadence observations from the Zwicky Transient Facility at low Galactic latitudes, we have discovered a new class of pulsating, hot, compact stars. We have found four candidates, exhibiting blue colors ($g-r\leq-0.1$ mag), pulsation amplitudes
T. Kupfer, E. Bauer, K. Burdge, E. Bellm, L. Bildsten, J. Fuller, J. Hermes, S. Kulkarni, T. Prince, J. Roestel, R. Dekany, D. Duev, M. Feeney, M. Giomi, M. Graham, S. Kaye, R. Laher, F. Masci, Michael E. Porter, R. Riddle, D. Shupe, Roger M. Smith, M. Soumagnac, P. Szkody, C. Ward   +24 more
semanticscholar   +1 more source

Searching for hot subdwarf stars from the LAMOST Spectra. II. Pure spectroscopic identification method for hot subdwarfs [PDF]

Nippon Tenmon Gakkai obun kenkyu hokoku, 2019
Employing a new machine learning method, named hierarchical extreme learning machine (HELM) algorithm, we identified 56 hot subdwarf stars in the first data release (DR1) of the Large Sky Area Multi-Object Fibre Spectroscopic Telescope (LAMOST) survey ...
Z. Lei, Yude Bu, Jingkun Zhao, P. N'emeth, Gang Zhao   +4 more
semanticscholar   +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

Single and Composite Hot Subdwarf Stars in the Light of 2MASS Photometry

, 2003
Utilizing the Two Micron All Sky Survey (2MASS) Second Incremental Data Release Catalog, we have retrieved near-IR magnitudes for several hundred hot subdwarfs (sdO and sdB stars) drawn from the "Catalogue of Spectroscopically Identified Hot Subdwarfs ...
Bixler J. V., Caloi V., Heber U., Hog E., Hog E., Kilkenny D., M. A. Stark, Moehler S., Mooney C. J., Perryman M. A. C., Richard A. Wade, Theissen A., Thejll P., Thejll P., Thejll P., Viton M.   +15 more
core   +2 more sources

Hot subdwarfs formed from the merger of two He white dwarfs [PDF]

, 2018
We perform stellar evolution calculations of the remnant of the merger of two He white dwarfs (WDs). Our initial conditions are taken from hydrodynamic simulations of double WD mergers and the viscous disc phase that follows. We evolve these objects from
J. Schwab
semanticscholar   +1 more source

Understanding Fundamental Properties and Atmospheric Features of Subdwarfs via a Case Study of SDSS J125637.13–022452.4 [PDF]

Astrophysical Journal, 2018
We present the distance-calibrated spectral energy distribution (SED) of the sdL3.5 subdwarf SDSS J125637.13−022452.4 (J1256−0224) using its Gaia DR2 parallax.
Eileen C. Gonzales, J. Faherty, J. Gagn'e, É. Artigau, D. B. Gagliuffi   +4 more
semanticscholar   +1 more source