Kazan Federal University Digital Repository

Dramatic spectral transition of X-ray pulsar GX 304-1 in low luminous state

Show simple item record

dc.contributor.author Tsygankov S.
dc.contributor.author Rouco Escorial A.
dc.contributor.author Suleimanov V.
dc.contributor.author Mushtukov A.
dc.contributor.author Doroshenko V.
dc.contributor.author Lutovinov A.
dc.contributor.author Wijnands R.
dc.contributor.author Poutanen J.
dc.date.accessioned 2020-01-15T21:49:50Z
dc.date.available 2020-01-15T21:49:50Z
dc.date.issued 2019
dc.identifier.issn 1745-3925
dc.identifier.uri https://dspace.kpfu.ru/xmlui/handle/net/156249
dc.description.abstract © 2018 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. We report on the discovery of a dramatic change in the energy spectrum of the X-ray pulsar GX 304-1 appearing at low luminosity. Particularly, we found that the cut-off power-law spectrum typical for accreting pulsars, including GX 304-1 at higher luminosities of L X 1/4 10 36 -10 37 erg s -1, transformed at lower luminosity of L X 1/4 10 34 erg s -1 to a two-component spectrum peaking around 5 and 40 keV. We suggest that the observed transition corresponds to a change of the dominant mechanism responsible for the deceleration of the accretion flow. We argue that the accretion flow energy at low accretion rates is released in the atmosphere of the neutron star, and the low-energy component in the source spectrum corresponds to the thermal emission of the optically thick, heated atmospheric layers. The most plausible explanations for the high-energy component are either the cyclotron emission reprocessed by the magnetic Compton scattering or the thermal radiation of deep atmospheric layers partly Comptonized in the overheated upper layers. Alternative scenarios are also discussed.
dc.relation.ispartofseries Monthly Notices of the Royal Astronomical Society: Letters
dc.subject accretion, accretion discs
dc.subject pulsars: general
dc.subject scattering
dc.subject stars: magnetic field
dc.subject stars: neutron
dc.subject X-rays: binaries
dc.title Dramatic spectral transition of X-ray pulsar GX 304-1 in low luminous state
dc.type Article
dc.relation.ispartofseries-issue 1
dc.relation.ispartofseries-volume 483
dc.collection Публикации сотрудников КФУ
dc.relation.startpage L144
dc.source.id SCOPUS17453925-2019-483-1-SID85062387662


Files in this item

This item appears in the following Collection(s)

  • Публикации сотрудников КФУ Scopus [22633]
    Коллекция содержит публикации сотрудников Казанского федерального (до 2010 года Казанского государственного) университета, проиндексированные в БД Scopus, начиная с 1970г.

Show simple item record

Search DSpace


Advanced Search

Browse

My Account