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Simulation and Fitting of Multi-Dimensional X-ray Data

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 نشر من قبل Daniel Dewey
 تاريخ النشر 2009
  مجال البحث فيزياء
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Astronomical data generally consists of 2 or more high-resolution axes, e.g., X,Y position on the sky or wavelength and position-along-one-axis (long-slit spectrometer). Analyzing these multi-dimension observations requires combining 3D source models (including velocity effects), instrument models, and multi-dimensional data comparison and fitting. A prototype of such a Beyond-XSPEC (Noble & Nowak, 2008) system is presented here using Chandra imag- ing and dispersed HETG grating data. Techniques used include: Monte Carlo event generation, chi-squared comparison, conjugate gradient fitting adapted to the Monte Carlo characteristics, and informative visualizations at each step. These simple baby steps of progress only scratch the surface of the computational potential that is available these days for astronomical analysis.

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