Issue |
A&A
Volume 423, Number 1, August III 2004
|
|
---|---|---|
Page(s) | 301 - 309 | |
Section | Stellar structure and evolution | |
DOI | https://doi.org/10.1051/0004-6361:20035743 | |
Published online | 29 July 2004 |
Evidence for a Neutron Star in the non-pulsating massive X-ray binary 4U2206+54
1
Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Escuela Politénica Superior, Universidad de Alicante, Ap. 99, 03080 Alicante, Spain e-mail: jmt@disc.ua.es
2
Institut für Astronomie und Astrophysik – Astronomie, Sand 1, 72076 Tübingen, Germany
3
Integral Science Data Centre, Chemin d'Ecogia 16, 1290 Versoix, Switzerland
4
ESA/ESTEC Research and Science Support Division, Noordwijk, The Netherlands
5
US Naval Research Laboratory, Space Science Division, 4555 Overlook Av., Washington, USA
Received:
25
November
2003
Accepted:
30
April
2004
We present an analysis of archival RXTE and BeppoSAX data of
the X-ray source 4U2206+54. For the first time, high energy data (≥30 keV) are analyzed for this source. The data are well
described by comptonization models (CompTT and
BMC) in which seed photons with temperatures between
1.1 keV and 1.5 keV are comptonized by a hot plasma at
50 keV thereby producing a hard tail which extends up to, at
least, 100 keV. We offer a new method of identification of
neutron star systems using a temperature – luminosity
relation. If a given X-ray source is characterized by a low
bolometric luminosity and a relatively high color blackbody
temperature (>1 keV) it has necessarily to be a neutron star
rather than a black hole. From these arguments it is shown that
the area of the soft photon source must be small ( km) and that the accretion disk, if present, must be
truncated very far from the compact object. Here we report on
the possible existence of a cyclotron line around 30 keV. The
presence of a neutron star in the system is strongly favored by
the available data.
Key words: stars: binaries: close / X-rays: binaries
© ESO, 2004
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.