Academic Journal
Preprint typeset using L ATEX style emulateapj REVEALING A COOL ACCRETION DISK IN THE ULTRALUMINOUS X-RAY SOURCE M81 X-9 (HOLMBERG IX X-1): EVIDENCE FOR AN INTERMEDIATE MASS BLACK HOLE
| العنوان: | Preprint typeset using L ATEX style emulateapj REVEALING A COOL ACCRETION DISK IN THE ULTRALUMINOUS X-RAY SOURCE M81 X-9 (HOLMBERG IX X-1): EVIDENCE FOR AN INTERMEDIATE MASS BLACK HOLE |
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| المؤلفون: | J. M. Miller, A. C. Fabian, M. C. Miller |
| المساهمون: | The Pennsylvania State University CiteSeerX Archives |
| المصدر: | http://arxiv.org/pdf/astro-ph/0310617v1.pdf. |
| سنة النشر: | 2008 |
| المجموعة: | CiteSeerX |
| الوصف: | We report the results of an analysis of two XMM-Newton/EPIC-pn spectra of the bright ultraluminous X-ray source M81 X-9 (Holmberg IX X-1), obtained in snapshot observations. Soft thermal emission is clearly revealed in spectra dominated by hard power-law components. Depending on the model used, M81 X-9 was observed at a luminosity of LX = 1.0−1.6×10 40 erg s 1 (0.3–10.0 keV). The variability previously observed in this source signals that it is an accreting source which likely harbors a black hole. Remarkably, accretion disk models for the soft thermal emission yield very low inner disk temperatures (kT = 0.17 − 0.29 keV, including 90 % confidence errors and variations between observations and disk models), and improve the fit statistic over any single-component continuum model at the 6σ level of confidence. This represents much stronger evidence for a cool disk than prior evidence which combined spectra from different observatories, and the strongest evidence of a cool disk in an ultraluminous X-ray source apart from NGC 1313 X-1. Like NGC 1313 X-1, scaling the temperatures measured in M81 X-9 to those commonly seen in stellar-mass Galactic black holes at their highest observed fluxes (kT ≃ 1 keV) may imply that M81 X-9 harbors a black hole with a mass on the order of 10 3 M⊙; the measured disk component normalization and broad-band luminosity imply black hole masses on the order of 10 2 M⊙. It is therefore possible that these sources harbor 10 3 M ⊙ black holes accreting at LX ≃ 0.1 × LEdd. While these results |
| نوع الوثيقة: | text |
| وصف الملف: | application/pdf |
| اللغة: | English |
| Relation: | http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.338.339; http://arxiv.org/pdf/astro-ph/0310617v1.pdf |
| الاتاحة: | http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.338.339 http://arxiv.org/pdf/astro-ph/0310617v1.pdf |
| Rights: | Metadata may be used without restrictions as long as the oai identifier remains attached to it. |
| رقم الانضمام: | edsbas.9622AC73 |
| قاعدة البيانات: | BASE |
| الوصف غير متاح. |