2005A&A...443..599P


Query : 2005A&A...443..599P

2005A&A...443..599P - Astronomy and Astrophysics, volume 443, 599-608 (2005/11-4)

Resolving the hard X-ray emission of GX 5-1 with INTEGRAL.

PAIZIS A., EBISAWA K., TIKKANEN T., RODRIGUEZ J., CHENEVEZ J., KUULKERS E., VILHU O. and COURVOISIER T.J.-L.

Abstract (from CDS):

We present the study of one year of INTEGRAL data on the neutron star low mass X-ray binary GX 5-1. Thanks to the excellent angular resolution and sensitivity of INTEGRAL, we are able to obtain a high quality spectrum of GX 5-1 from ∼5keV to ∼100keV, for the first time without contamination from the nearby black hole candidate GRS 1758-258 above 20keV. During our observations, GX 5-1 was mostly found in the horizontal and normal branch of its hardness intensity diagram. A clear hard X-ray emission is observed above ∼30keV which exceeds the exponential cut-off spectrum expected from lower energies. This spectral flattening may have the same origin of the hard components observed in other Z sources as it shares the property of being characteristic to the horizontal branch. The hard excess is explained by introducing Compton up-scattering of soft photons from the neutron star surface due to a thin hot plasma expected in the boundary layer. The spectral changes of GX 5-1 downward along the ``Z'' pattern in the hardness intensity diagram can be well described in terms of monotonical decrease of the neutron star surface temperature. This may be a consequence of the gradual expansion of the boundary layer as the mass accretion rate increases.

Abstract Copyright:

Journal keyword(s): X-rays: binaries - binaries (including multiple): close - stars: neutron - stars: individual: GX 5-1

Simbad objects: 12

goto Full paper

goto View the references in ADS

Number of rows : 12
N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2022
#notes
1 V* V818 Sco LXB 16 19 55.0692669024 -15 38 25.017666540 11.60 12.40 11.1     Oev 1570 0
2 4U 1642-45 LXB 16 45 47.7 -45 36 40     14.30     ~ 392 1
3 V* V1101 Sco LXB 17 05 44.4916006152 -36 25 23.049324480   20.10 18.6     ~ 417 0
4 NAME Galactic Center reg 17 45 39.60213 -29 00 22.0000           ~ 12903 0
5 X Sgr X-1 LXB 17 47 56.0 -26 33 49           ~ 357 0
6 [KRL2007b] 297 LXB 17 59 45.7 -22 01 39           ~ 61 1
7 4U 1758-25 LXB 18 01 09.7308060816 -25 04 44.120221284     11.08     ~ 628 1
8 2XMM J180112.4-254436 LXB 18 01 12.40 -25 44 36.1           ~ 371 1
9 X Sgr X-3 LXB 18 01 32.3 -20 31 44           ~ 224 1
10 V* NP Ser LXB 18 16 01.389 -14 02 10.62   18.8       K 616 2
11 V* V1341 Cyg LXB 21 44 41.1544345272 +38 19 17.066570988 15.00 15.13 14.68 15.00   A9III 1104 1
12 NAME Galactic Bulge reg ~ ~           ~ 3845 0

To bookmark this query, right click on this link: simbad:objects in 2005A&A...443..599P and select 'bookmark this link' or equivalent in the popup menu


2022.05.21-12:10:59

© Université de Strasbourg/CNRS

    • Contact