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Related papers: Giant Outbursts in Be/X-ray Binaries

200 papers

The optical light curve of the Be/neutron star binary AX J0049.4-7323 has been investigated using data from the MACHO and OGLE-II projects. This X-ray source, whose neutron star has a very slow rotation rate (P_pulse=755.5 sec), shows…

Astrophysics · Physics 2009-11-10 A. P. Cowley , P. C. Schmidtke

We investigate the spectroscopic characteristics of the optical components of Be/X-ray binary systems, using data collected during our seven-year monitoring campaign. We find examples of major changes in the emission line profiles…

Astrophysics · Physics 2007-05-23 I. Negueruela , P. Reig , M. J. Coe , J. Fabregat

We examine Be star discs in highly eccentric Be/X-ray systems. We use a three-dimensional smoothed particle hydrodynamics (SPH) code to model the structure of the Be star disc and investigate its interactions with the secondary star over…

Solar and Stellar Astrophysics · Physics 2025-02-10 R. G. Rast , C. E. Jones , M. W. Suffak , A. C. Carciofi

AX J0049.4-7323 is a Be/X-ray binary that shows an unusual and poorly understood optical variability that consists of periodic and bright optical outbursts, simultaneous with X-ray outbursts, characterised by a highly asymmetric profile.…

High Energy Astrophysical Phenomena · Physics 2019-01-23 L. Ducci , C. Malacaria , P. Romano , L. Ji , E. Bozzo , I. Saathoff , A. Santangelo , A. Udalski

As the largest population of high mass X-ray binaries, Be/X-ray binaries provide an excellent laboratory to investigate the extreme physics of neutron stars. It is generally accepted that Be stars possess a circumstellar disc, providing an…

High Energy Astrophysical Phenomena · Physics 2019-07-10 R. O. Brown , M. J. Coe , W. C. G. Ho , A. T. Okazaki

Many neutron star low-mass X-ray binaries (NS LMXBs) with short orbital periods (~hours) cycle between outburst and quiescent phases, and thus provide an excellent way to study the accretion process. The cause of such outbursts is believed…

High Energy Astrophysical Phenomena · Physics 2025-04-11 Sayantan Bhattacharya , Sudip Bhattacharyya

we study the long-term evolution of the accretion disk around the neutron star in Be/X-ray binaries. We confirm the earlier result by Hayasaki & Okazaki (2004) that the disk evolves via a two-stage process, which consists of the initial…

Astrophysics · Physics 2007-05-23 Kimitake Hayasaki , Atsuo T. Okazaki

The transient X-ray pulsar GRO J1008-57 was previously found to exhibit Type I outbursts occurring at stable orbital phases before its first observed Type II outburst in 2012. In this work, we extend the study to investigate the phase…

High Energy Astrophysical Phenomena · Physics 2026-05-20 Yongfeng Hu , Hua Xiao , Sergey S. Tsygankov , Long Ji , Juri Poutanen , Runting Huang

Type-I X-ray bursts are thermonuclear explosions caused by the unstable burning of accreted material on the surface of neutron stars. We report the detection of seven type-I X-ray bursts from the ultracompact X-ray binary M15 X-2 observed…

High Energy Astrophysical Phenomena · Physics 2025-03-07 María Alejandra Díaz Teodori , Jari J. E. Kajava , Celia Sánchez-Fernández , Andrea Sanna , Mason Ng , Juri Poutanen

We numerically study the long-term evolution of the accretion disc around the neutron star in a coplanar Be/X-ray binary with a short period and a moderate eccentricity. From three dimensional Smoothed Particle Hydrodynamics simulations, we…

Astrophysics · Physics 2009-11-11 K. Hayasaki , Atsuo T. Okazaki

We study accretion onto the neutron star in Be/X-ray binaries, using a 3D SPH code and the data imported from a high resolution simulation by Okazaki et al.\ (2002) for a coplanar system with a short period ($P_{\rm orb}=24.3 \rm d$) and…

Astrophysics · Physics 2007-05-23 Kimitake Hayasaki , Atsuo. T. Okazaki

Accretion disc outbursts are re-occurring events observed in various astrophysical systems, including X-ray binaries and cataclysmic variables. These outbursts are characterized by a sudden increase in luminosity due to various…

High Energy Astrophysical Phenomena · Physics 2024-09-19 Liza Devi , Asish Jyoti Boruah , Biplob Sarkar

Be X-ray binaries (BeXRBs) may show strong X-ray and optical variability, and can exhibit some of the brightest outbursts that break through the Eddington limit. Major X-ray outbursts are often accompanied by strong optical flares that…

High Energy Astrophysical Phenomena · Physics 2025-06-04 G. Vasilopoulos

Be/X-ray binary systems provide an excellent opportunity to study the physics around neutron stars through the study of the behaviour of matter around them. Intermediate and low-luminosity type outbursts are interesting because they provide…

High Energy Astrophysical Phenomena · Physics 2019-08-15 M. D. Caballero-Garcia , A. Camero-Arranz , M. Ozbey Arabaci , R. Hudec

X-rays trace accretion onto compact objects in binaries with low mass companions at rates ranging up to near Eddington. Accretion at high rates onto neutron stars goes through cycles with time-scales of days to months. At lower average…

Astrophysics · Physics 2009-11-06 Jean H. Swank

The Small Magellanic Cloud (SMC) Be/X-ray binary pulsar SXP6.85 = XTE J0103-728 underwent a large Type II outburst beginning on 2008 August 10. The source was consistently seen for the following 20 weeks (MJD = 54688 - 54830). We present…

High Energy Astrophysical Phenomena · Physics 2015-05-14 L. J. Townsend , M. J. Coe , V. A. McBride , A. J. Bird , M. P. E. Schurch , R. H. D. Corbet , F. Haberl , J. L. Galache , A. Udalski

Type II bursts are thought to arise from instabilities in the accretion flow onto a neutron star in an X-ray binary. Despite having been known for almost 40 years, no model can yet satisfactorily account for all their properties. To shed…

High Energy Astrophysical Phenomena · Physics 2015-06-23 T. Bagnoli , J. J. M. in 't Zand , C. R. D'Angelo , D. K. Galloway

In this paper we report on the optical and X-ray behaviour of the Be X-ray binary, SXP 91.1, during a recent type I outburst. We monitored the outburst using the Neil Gehrels Swift Observatory. These data were supported by optical data from…

High Energy Astrophysical Phenomena · Physics 2019-08-21 Itumeleng Monageng , Malcolm Coe , Jamie Kennea , Lee Townsend , David Buckley , Vanessa McBride , Andrzej Udalski , Phil Evans , Paul Roche

We present recent contemporaneous X-ray and optical observations of the Be/X-ray binary system A\,0535+26 with the \textit{Fermi}/Gamma-ray Burst Monitor (GBM) and several ground-based observatories. These new observations are put into the…

In order to study the growth and evolution of circumstellar disks around classical Be stars, we analyze optical time-series photometry from the KELT survey with simultaneous infrared and visible spectroscopy from the APOGEE survey and BeSS…