BROADBAND SPECTRAL INVESTIGATIONS OF SGR J1550–5418 BURSTS

dc.citation.firstpage54en_US
dc.citation.journalTitleThe Astrophysical Journalen_US
dc.citation.lastpage66en_US
dc.citation.volumeNumber756en_US
dc.contributor.authorLin, Linen_US
dc.contributor.authorBaring, Matthew G.en_US
dc.contributor.authorGranot, Jonathanen_US
dc.contributor.authorKouveliotou, Chryssaen_US
dc.contributor.authorKaneko, Yukien_US
dc.contributor.authorVan Der Horst, Alexanderen_US
dc.contributor.authorGruber, Daviden_US
dc.contributor.authorVon Kienlin, Andreasen_US
dc.contributor.authorYounes, Georgeen_US
dc.contributor.authorWatts, Anna L.en_US
dc.contributor.authorGehrels, Neilen_US
dc.date.accessioned2013-03-13T19:09:52Zen_US
dc.date.available2014-03-19T05:10:04Zen_US
dc.date.issued2012en_US
dc.description.abstractWe present the results of our broadband spectral analysis of 42 SGR J1550−5418 bursts simultaneously detected with the Swift/X-ray Telescope (XRT) and the Fermi/Gamma-ray Burst Monitor (GBM), during the 2009 January active episode of the source. The unique spectral and temporal capabilities of the XRT windowed timing mode have allowed us to extend the GBM spectral coverage for these events down to the X-ray domain (0.5–10 keV). Our earlier analysis of the GBM data found that the SGR J1550−5418 burst spectra were described equally well with either a Comptonized model or with two blackbody functions; the two models were statistically indistinguishable. Our new broadband (0.5–200 keV) spectral fits show that, on average, the burst spectra are better described with two blackbody functions than with the Comptonized model. Thus, our joint XRT–GBM analysis clearly shows for the first time that the SGR J1550−5418 burst spectra might naturally be expected to exhibit a more truly thermalized character, such as a two-blackbody or even a multi-blackbody signal. Using the Swift and RXTE timing ephemeris for SGR J1550−5418 we construct the distribution of the XRT burst counts with spin phase and find that it is not correlated with the persistent X-ray emission pulse phase from SGR J1550−5418. These results indicate that the burst emitting sites on the neutron star need not to be co-located with hot spots emitting the bulk of the persistent X-ray emission. Finally, we show that there is a significant pulse phase dependence of the XRT burst counts, likely demonstrating that the surface magnetic field of SGR J1550−5418 is not uniform over the emission zones, since it is anticipated that regions with stronger surface magnetic field could trigger bursts more efficiently.en_US
dc.embargo.terms1 yearen_US
dc.identifier.citationLin, Lin, Baring, Matthew G., Granot, Jonathan, et al.. "BROADBAND SPECTRAL INVESTIGATIONS OF SGR J1550–5418 BURSTS." <i>The Astrophysical Journal,</i> 756, (2012) The American Astronomical Society: 54-66. http://dx.doi.org/10.1088/0004-637X/756/1/54.en_US
dc.identifier.doihttp://dx.doi.org/10.1088/0004-637X/756/1/54en_US
dc.identifier.urihttps://hdl.handle.net/1911/70568en_US
dc.language.isoengen_US
dc.publisherThe American Astronomical Societyen_US
dc.rightsArticle is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.en_US
dc.subject.keywordpulsarsen_US
dc.subject.keywordindividual (SGR J1550−5418, 1E 1547.0−5408, PSR J1550−5418) – starsen_US
dc.subject.keywordneutron – X-raysen_US
dc.subject.keywordburstsen_US
dc.titleBROADBAND SPECTRAL INVESTIGATIONS OF SGR J1550–5418 BURSTSen_US
dc.typeJournal articleen_US
dc.type.dcmiTexten_US
dc.type.publicationpublisher versionen_US
Files
Original bundle
Now showing 1 - 1 of 1
Loading...
Thumbnail Image
Name:
BROADBAND-SPECTRAL.pdf
Size:
1.64 MB
Format:
Adobe Portable Document Format
License bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
license.txt
Size:
1.61 KB
Format:
Item-specific license agreed upon to submission
Description: