Zobrazeno 1 - 10
of 22
pro vyhledávání: '"R. C. North"'
Autor:
L. Morales-Rueda, Danny Steeghs, Eduardo Unda-Sanzana, Janet H. Wood, R. C. North, T. R. Marsh
Publikováno v:
Astronomy & Astrophysics. 405:249-261
We present high resolution optical and UV spectra of the 46 min orbital period, helium binary, GP Com. Our data contains simultaneous photometric correction which confirms the flaring behaviour observed in previous optical and UV data. In this system
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::a2d7007c3ba9f927b92c665ed681a251
https://doi.org/10.1051/0004-6361:20030552
https://doi.org/10.1051/0004-6361:20030552
Publikováno v:
Monthly Notices of the Royal Astronomical Society. 338:752-764
Subdwarf B (sdB) stars are thought to be core helium burning stars with low mass hydrogen envelopes. In recent years it has become clear that many sdB stars lose their hydrogen through interaction with a binary companion and continue to reside in bin
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::a2e4c6af5883cda536074cdd7917e198
https://doi.org/10.1046/j.1365-8711.2003.06088.x
https://doi.org/10.1046/j.1365-8711.2003.06088.x
Publikováno v:
White Dwarfs ISBN: 9781402013645
Subdwarf B (sdB) stars are thought to be helium burning stars with low mass hydrogen envelopes. Several evolutionary paths have been proposed to explain the formation of these systems. One of these scenarios is the evolution of the sdB progenitor wit
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::b48eb388a974f948ffadbf045f5b5b25
https://doi.org/10.1007/978-94-010-0215-8_15
https://doi.org/10.1007/978-94-010-0215-8_15
Publikováno v:
MILCOM 97 MILCOM 97 Proceedings.
The Naval Command, Control and Ocean Surveillance Center's RDT&E Division (NRaD) and the Jet Propulsion Lab (JPL) installed JPL's Advanced Communications Technology Satellite (ACTS) mobile terminal (AMT) on USS Princeton (CG 59) in July 1996. The AMT
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::8e10e183c4e53caa68b089769499bd09
https://doi.org/10.1109/milcom.1997.646747
https://doi.org/10.1109/milcom.1997.646747
Autor:
T. R. Marsh, L. Morales-Rueda, R. C. North, Pierre F. L. Maxted, Warrick A. Lawson, Uli Heber
We present lightcurves of four binary subdwarf B stars, Ton 245, Feige 11, PG1432+159 and PG1017-086. We also present new spectroscopic data for PG1017-086 from which we derive its orbital period, P=0.073d, and the mass function, f_m = 0.0010 +/- 0.0
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::84866049ef07bd9a2ef0c1ad306528c5
http://arxiv.org/abs/astro-ph/0202177
http://arxiv.org/abs/astro-ph/0202177
Although a large number of orbital periods of cataclysmic variable stars (CVs) have been measured, comparison of period and luminosity distributions with evolutionary theory is affected by strong selection effects. A test has been discovered which is
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::78ea66c24c92d2c97ac518b840dbeca1
Publikováno v:
Astrotomography ISBN: 9783540422136
We present Doppler maps of Hα (6562.76A) emission of 4 well-known dwarf novae, SS Cyg, AH Her, EM Cyg and V426 Oph. All 4 systems were in quiescence during our observations. All of them have visible mass donor stars allowing us to establish precise
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::48ae4c8fca8fc4e4634040486ec72443
https://doi.org/10.1007/3-540-45339-3_3
https://doi.org/10.1007/3-540-45339-3_3
Publikováno v:
Astrotomography ISBN: 9783540422136
We present high resolution spectra of the AM CVn helium binary GP Com at two different wavelength ranges. The spectra show the same flaring behaviour observed in previous UV and optical data. We find that the central spike contributes to the flare sp
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::e3fc73a756b6c4f222b37e7cac5e3619
https://doi.org/10.1007/3-540-45339-3_2
https://doi.org/10.1007/3-540-45339-3_2
(Abbreviated) We have used precise radial velocity measurements of subdwarf-B stars from the Palomar-Green catalogue to look for binary extreme horizontal branch (EHB) stars. We identify 36 EHB stars in our sample and find that at least 21 of these s
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::da46fdfa9b73d6d4b746f46844a3194c
We present spectra of the pulsating sdB star KPD1930+2752 which confirm that this star is a binary. The radial velocities measured from the H-alpha and HeI6678 spectral lines vary sinusoidally with the same period (2h 17m) as the ellipsoidal variabil
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::e944604c99d83bad9ef6ac9005a91120