Results 41 to 50 of about 370 (81)

Evolution of the Inner Accretion Flow and the White Dwarf Spin Pulse during the 2023 Outburst in GK Persei

The Astrophysical Journal
We present our X-ray and optical observations performed by NICER, NuSTAR, and Tomo-e Gozen during the 2023 outburst in the intermediate polar GK Persei. The X-ray spectrum consisted of three components: blackbody (BB) emission of several tens of eVs from
Mariko Kimura, Takayuki Hayashi, Yuuki Wada, Wataru Iwakiri, Shigeyuki Sako, Martina Veresvarska, Simone Scaringi, Noel Castro-Segura, Christian Knigge, Keith C. Gendreau, Zaven Arzoumanian   +10 more
doaj   +1 more source

Classifying Optical (Out)bursts in Cataclysmic Variables: The Distinct Observational Characteristics of Dwarf Novae, Micronovae, Stellar Flares, and Magnetic Gating

The Astrophysical Journal Letters
Cataclysmic variables can experience short optical brightenings, which are commonly attributed to phenomena such as dwarf novae outbursts, micronovae, donor flares, or magnetic gating bursts.
Krystian Iłkiewicz, Simone Scaringi, Martina Veresvarska, Domitilla De Martino, Colin Littlefield, Christian Knigge, John A. Paice, Anwesha Sahu   +7 more
doaj   +1 more source

Asteroseismology

, 2012
Asteroseismology is the determination of the interior structures of stars by using their oscillations as seismic waves. Simple explanations of the astrophysical background and some basic theoretical considerations needed in this rapidly evolving field ...
A Baglin, A Gautschy, A Miglio, A Mukadam, AA Pamyatnykh, AB Kaye, AJ Brickhill, AU Landolt, B Mosser, C Aerts, C Aerts, C Waelkens, C Waelkens, D Kilkenny, DE Mkrtichian, DE Winget, DE Winget, DE Winget, DE Winget, DO Gough, DR Reese, DW Kurtz, DW Kurtz, DW Kurtz, EB Frost, EL Robinson, EM Green, F-L Deubner, G Handler, G Handler, G Handler, G Handler, G Maeder, G Torres, G Walker, H Bruntt, H Kjeldsen, H Saio, J Christensen-Dalsgaard, J Christensen-Dalsgaard, J Daszyńska-Daszkiewicz, J Daszyńska-Daszkiewicz, J Daszyńska-Daszkiewicz, J Goodricke, J Ridder De, J-P Montagner, JH Telting, JH Telting, JP Cox, JR Percy, L Eyer, LL Kiss, M Aizenman, M Asplund, M Suran, M Tassoul, M-A Dupret, MD Reed, MH Montgomery, MH Montgomery, N Baker, P Brassard, P Dufour, PA Woudt, PW Jones, R Samadi, RD Watson, RE Nather, RE Nather, RL Gilliland, S Frandsen, S Hekker, S Rosseland, S Talon, SO Kepler, SS Vogt, T Kallinger, TR Bedding, TR Bedding, TS Metcalfe, TS Metcalfe, WA Dziembowski, WA Dziembowski, WA Dziembowski, WA Dziembowski, WD Pesnell, WJ Chaplin, WW Campbell   +87 more
core   +1 more source

Spectroscopic diagnostics of dust formation and evolution in classical nova ejecta [PDF]

, 2018
A fraction of classical novae form dust during the early stages of their outbursts. The classical CO nova V5668 Sgr (Nova Sgr. 2015b) underwent a deep photometric minimum about 100 days after outburst that was covered across the spectrum. A similar event
Aquino, Ivan De Gennaro, Kuin, N. Paul, Mason, Elena, Shore, Steven N.   +3 more
core   +3 more sources

Stochastic Optical Variability and an rms–Flux Relation in the Intermediate Polar EP240309a

The Astrophysical Journal Supplement Series
Magnetic cataclysmic variables provide a natural laboratory for studying how accretion interacts with compact-object magnetospheres and generates stochastic variability.
S.-Y. Wu, Y.-D. Hu, I. Pérez-García, A. J. Castro-Tirado, M. Gritsevich, E. J. Fernández-García, M. D. Caballero-García, S. Guziy, G. García-Segura, R. Sánchez-Ramírez, C. D. Kilpatrick, C. R. Bom, L. Santana, A. Santos, P. J. Meintjes, H. J. van Heerden, A. Martín-Carrillo, L. Hanlon, A. Maury, D.-R. Xiong, B.-B. Zhang   +20 more
doaj   +1 more source

First axion bounds from a pulsating helium-rich white dwarf star [PDF]

, 2016
The Peccei-Quinn mechanism proposed to solve the CP problem of Quantum Chromodynamics has as consequence the existence of axions, hypothetical weakly interacting particles whose mass is constrained to be on the sub-eV range.
Althaus, Leandro Gabriel, Battich, Tiara, Corsico, Alejandro Hugo, Miller Bertolami, Marcelo Miguel   +3 more
core   +3 more sources

Discovery of Spin-pulse Correlated Magnetic Gating Bursts in the Long-period Intermediate Polar PBC J0801.2–4625

The Astrophysical Journal
We present the first discovery of small-amplitude (tens of millimagnitudes), short-duration (several hours) episodic brightenings in the Transiting Exoplanet Survey Satellite (TESS) light curve of the intermediate polar PBC J0801.2–4625 that are strongly
Vishal Joshi, Akash Sundriyal
doaj   +1 more source

Ultraviolet spectroscopy of old novae and symbiotic stars [PDF]

The IUE spectra are presented for two old novae and for two of the symbiotic variables. Prominent emission line spectra are revealed as a continuum whose appearance is effected by the system inclination.
Ferland, G. J., Lambert, D. L., Shields, G. A., Slovak, M. H.   +3 more
core   +1 more source

Multiwavelength Photometry and Hubble Space Telescope Spectroscopy of the Old Nova V842 Centaurus

, 2013
We present ground-based optical and near infrared photometric observations and Hubble Space Telescope COS spectroscopic observations of the old nova V842 Cen (Nova Cen 1986).
Godon, Patrick, Henden, Arne, Mukadam, Anjum, Sion, Edward M., Szkody, Paula, Walter, Frederic, Warner, Brian, Woudt, Patrick   +7 more
core   +1 more source

The Chemical Compositions of the Type II Cepheids -- The BL Her and W Vir Variables

, 2007
Abundance analyses from high-resolution optical spectra are presented for 19 Type II Cepheids in the Galactic field. The sample includes both short-period (BL Her) and long-period (W Vir) stars.
Berdnikov L. N., Bono G., David L. Lambert, Dean J. F., Diethelm R., Edvardsson B., Gingold R. A., Gingold R. A., Gonzalez G., Kinman T., Kraft R. P., Lloyd Evans T., Lloyd Evans T., Lloyd Evans T., McClure R. D., Rodgers A. W., Rodgers A. W., Sanwal N. N., Stobie R. S., Sunetra Giridhar, Thomas Maas, Van Winckel H., Vinko J., Wallerstein G.   +23 more
core   +1 more source