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GRO J1655-40: from ASCA and XMM-Newton Observations

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 نشر من قبل Xiaoling Zhang
 تاريخ النشر 2007
  مجال البحث فيزياء
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We have analysed four ASCA observations (1994--1995, 1996--1997) and three XMM-Newton observations (2005) of this source, in all of which the source is in high/soft state. We modeled the continuum spectra with relativistic disk model kerrbb, estimated the spin of the central black hole, and constrained the spectral hardening factor f_col and the distance. If kerrbb model applies, for normally used value of f_col, the distance cannot be very small, and f_col changes with observations.



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