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SN 1987A at High Resolution

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 نشر من قبل Daniel Dewey
 تاريخ النشر 2013
  مجال البحث فيزياء
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 تأليف Daniel Dewey




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Handed the baton from ROSAT, early observations of SN 1987A with the Chandra HETG and the XMM-Newton RGS showed broad lines with a FWHM of 10^4 km/s: the SN blast wave was continuing to shock the H II region around SN 1987A. Since then, its picturesque equatorial ring (ER) has been shocked, giving rise to a growing, dominant narrow-lined component. Even so, current HETG and RGS observations show that a broad component is still present and contributes 20% of the 0.5--2 keV flux. SN 1987As X-ray behavior can be modeled with a minimum of free parameters as the sum of two simple 1D hydrodynamic simulations: i) an on-going interaction with H II region material producing the broad emission lines and most of the 3--10 keV flux, and ii) an interaction with the dense, clumpy ER material that dominates the 0.5--2 keV flux. Toward the future, we predict a continued growth of the broad component but a drop in the 0.5--2 keV flux, once no new dense ER material is being shocked. When? Time, and new data, will tell.



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