2010A&A...519A..37F


C.D.S. - SIMBAD4 rel 1.7 - 2021.03.06CET06:55:11

2010A&A...519A..37F - Astronomy and Astrophysics, volume 519, A37-37 (2010/9-1)

X-ray variation statistics and wind clumping in Vela X-1.

FUERST F., KREYKENBOHM I., POTTSCHMIDT K., WILMS J., HANKE M., ROTHSCHILD R.E., KRETSCHMAR P., SCHULZ N.S., HUENEMOERDER D.P., KLOCHKOV D. and STAUBERT R.

Abstract (from CDS):

We investigate the structure of the wind in the neutron star X-ray binary system Vela X-1 by analyzing its flaring behavior. Vela X-1 shows constant flaring, with some flares reaching fluxes of more than 3.0Crab between 20-60keV for several 100s, while the average flux is around 250mCrab. We analyzed all archival INTEGRAL data, calculating the brightness distribution in the 20-60keV band, which, as we show, closely follows a log-normal distribution. Orbital resolved analysis shows that the structure is strongly variable, explainable by shocks and a fluctuating accretion wake. Analysis of RXTE ASM data suggests a strong orbital change of NH. Accreted clump masses derived from the INTEGRAL data are on the order of 5x1019-1021g. We show that the lightcurve can be described with a model of multiplicative random numbers. In the course of the simulation we calculate the power spectral density of the system in the 20-100keV energy band and show that it follows a red-noise power law. We suggest that a mixture of a clumpy wind, shocks, and turbulence can explain the measured mass distribution. As the recently discovered class of supergiant fast X-ray transients (SFXT) seems to show the same parameters for the wind, the link between persistent HMXB like Vela X-1 and SFXT is further strengthened.

Abstract Copyright:

Journal keyword(s): accretion, accretion disks - X-rays: binaries - X-rays: individual: Vela X-1 - methods: statistical

Simbad objects: 5

goto Full paper

goto View the reference in ADS

Number of rows : 5

N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2021
#notes
1 V* BQ Cam HXB 03 34 59.9116460415 +53 10 23.296351781   17.16 15.42 14.26 13.04 O8.5Ve 411 1
2 HD 74194 HXB 08 40 47.7915105936 -45 03 30.231146034 7.05 7.77 7.55 8.70   O8.5Ib-II(f)p 181 0
3 V* GP Vel HXB 09 02 06.8610736194 -40 33 16.896402010 6.85 7.37 6.87 6.31 6.05 B0.5Ia 1385 0
4 4U 1908+075 HXB 19 10 48.2141670291 +07 35 51.715745251           O7.5-9.5sg 105 0
5 HD 226868 HXB 19 58 21.6758193269 +35 12 05.782512305 9.38 9.72 8.91 8.42   O9.7Iabpvar 3984 0

    Equat.    Gal    SGal    Ecl

To bookmark this query, right click on this link: simbad:objects in 2010A&A...519A..37F and select 'bookmark this link' or equivalent in the popup menu


2021.03.06-06:55:11

© Université de Strasbourg/CNRS

    • Contact