The soft gamma-ray spectrum of A0535+26: Detection of an absorption feature at 110 keV by OSSE

Grove, J. E.; Strickman, M. S.; Johnson, W. N.; Kurfess, J. D.; Kinzer, R. L.; Starr, C. H.; Jung, G. V.; Kendziorra, E.; Kretschmar, P.; Maisack, M.; Staubert, R.

doi:10.1086/187706

Cited by 66 publications

(73 citation statements)

References 16 publications

(22 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The energy spectrum of A 0535+262 is modified by two absorption features at ∼ 45 keV and ∼ 100 keV, which are interpreted as a cyclotron absorption line and its first harmonic. The magnetic field strength on the neutron star surface can be estimated as B ∼ 4 × 10 12 G (Kendziorra et al, 1994;Grove et al, 1995). A comprehensive analysis of the INTEGRAL, RXTE, and Suzaku spectral data does not reveal variations of the cyclotron energy during outbursts .…”

Section: Discussionmentioning

confidence: 99%

High-mass X-ray binaries in the Milky Way

Walter

Lutovinov

Bozzo

et al. 2015

Astron Astrophys Rev

230

234

View full text Add to dashboard Cite

High-mass X-ray binaries are fundamental in the study of stellar evolution, nucleosynthesis, structure and evolution of galaxies and accretion processes. Hard X-rays observations by INTEGRAL and Swift have broadened significantly our understanding in particular for the super-giant systems in the Milky Way, which number has increased by almost a factor of three. INTEGRAL played a crucial role in the discovery, study and understanding of heavily obscured systems and of fast X-ray transients. Most super-giant systems can now be classified in three categories: classical/obscured, eccentric and fast transient.The classical systems feature low eccentricity and variability factor of ∼ 10 3 , mostly driven by hydrodynamic phenomena occurring on scales larger than the accretion radius. Among them, systems with short orbital periods and close to Roche-Lobe overflow or with slow winds, appear highly obscured. In eccentric systems, the variability amplitude can reach even higher factors, because of the contrast of the wind density along the orbit. Four super-giant systems, featuring fast outbursts, very short orbital periods and anomalously low accretion rates, are not yet understood.Simulations of the accretion processes on relatively large scales have progressed and reproduce parts of the observations. The combined effects of wind

show abstract

Section: Discussionmentioning

confidence: 99%

High-mass X-ray binaries in the Milky Way

Walter

Lutovinov

Bozzo

et al. 2015

Astron Astrophys Rev

230

234

View full text Add to dashboard Cite

show abstract

“…Two cyclotron absorption lines at about 50 keV and 100 keV were reported and interpreted as the fundamental and the first harmonic and implying a magnetic field strength of about 4.3 × 10 12 G (Kendziorra et al 1994;Caballero et al 2007). While the presence of the fundamental line at about 50 keV was initially questioned (Grove et al 1995;Araya & Harding 1996), newer analyses clearly confirm the presence of both lines and their interpretation as a fundamental cyclotron feature and its first harmonic (Caballero et al 2007). …”

Section: Introductionmentioning

confidence: 99%

A 0535+26 in the April 2010 outburst: probing the accretion regime at work

Müller

Klochkov

Caballero

et al. 2013

A&A

View full text Add to dashboard Cite

Context. A number of accreting X-ray pulsars experience spectral changes, both on the long time scales and on the time scales of the neutron star spin period. The sources seem to form two distinct groups that differ by the type of the spectral variations with flux. Such a bimodality probably reflects two different regimes of accretion that may result in a particular pulsar depending on its luminosityso-called sub-and super-critical regimes. Aims. We investigated the behavior of the spectral parameters of the Be/X-ray binary system A 0535+26, as a function of flux and pulse phase. Methods. We used the data collected with INTEGRAL and RXTE during the April 2010 outburst of the source. We analyzed the phase-averaged and phase-resolved spectra and performed pulse-to-pulse spectral analysis of the pulsar. Results. Our analysis reveals variability in the continuum parameters of the source's pulse-averaged spectrum with flux. The pulseaveraged cyclotron line energy does not change with the source luminosity during the outburst, which is consistent with previous studies. Our pulse-phase resolved and pulse-to-pulse analyses reveal, however, indications for a positive correlation of the cyclotron line energy with flux, as well as a flux-dependence of the continuum parameters. Based on the observed behavior, we argue that A 0535+26 operates at the sub-critical accretion regime.

show abstract

“…A 0535+26 shows two cyclotron lines at ∼45 keV (fundamental) and ∼100 keV (first harmonic). These lines were observed in 1994 with HEXE and OSSE ([13], [14]), and have later been confirmed with INTEGRAL , RXTE [15] and Suzaku [16]. From the cyclotron lines, the magnetic field is inferred to be B∼4×10 12 G [17].…”

Section: Introductionmentioning

confidence: 78%

New outburst of A0535+26 observed with INTEGRAL, RXTE and Suzaku

Caballero¹,

Pottschmidt²,

Barragán³

et al. 2010

Proceedings of the Extreme Sky: Sampling the Universe Above 10 keV — PoS(extremesky2009)

View full text Add to dashboard Cite

A normal outburst of the Be/X-ray binary system A0535+26 has taken place in August 2009. It is the fourth in a series of normal outbursts that have occured around the periastron passage of the source, but is unusual by starting at an earlier orbital phase and by presenting a peculiar double-peaked light curve. A first "flare" (lasting about 9 days from MJD 55043 on) reached a flux of 440 mCrab. The flux then decreased to less than 220 mCrab, and increased again reaching 440 mCrab around the periastron at MJD 55057. Target of Opportunity observations have been performed with INTEGRAL, RXTE and Suzaku. First results of these observations are presented, with special emphasis on the cyclotron lines present in the X-ray spectrum of the source, as well as in the pulse period and energy dependent pulse profiles of the source.

show abstract

The soft gamma-ray spectrum of A0535+26: Detection of an absorption feature at 110 keV by OSSE

Cited by 66 publications

References 16 publications

High-mass X-ray binaries in the Milky Way

High-mass X-ray binaries in the Milky Way

A 0535+26 in the April 2010 outburst: probing the accretion regime at work

New outburst of A0535+26 observed with INTEGRAL, RXTE and Suzaku

Contact Info

Product

Resources

About