HEASARC Staff Scientist Position - Applications are now being accepted for a Staff Scientist with significant experience and interest in the technical aspects of astrophysics research, to work in the High Energy Astrophysics Science Archive Research Center (HEASARC) at NASA Goddard Space Flight Center (GSFC) in Greenbelt, MD. Refer to the AAS Job register for full details.

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weight

change weighting used in computing statistic

Change the weighting function used in the calculation of chi-squared.

Syntax: weight [standard | gehrels | churazov | model]

standard weighting uses $\sqrt{N}$ or the statistical error given in the input spectrum. gehrels weighting uses $1+\sqrt{N+0.75}$, a better approximation when N is small (Gehrels, N. 1986, ApJ 303, 336). churazov weighting uses the suggestion of Churazov et al. (1996, ApJ 471, 673) to estimate the weight for a given channel by averaging the counts in surrounding channels. model weighting uses the value of the model, not the data, to estimate the weight.


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Last modified: Friday, 23-Aug-2024 13:20:40 EDT

HEASARC Staff Scientist Position - Applications are now being accepted for a Staff Scientist with significant experience and interest in the technical aspects of astrophysics research, to work in the High Energy Astrophysics Science Archive Research Center (HEASARC) at NASA Goddard Space Flight Center (GSFC) in Greenbelt, MD. Refer to the AAS Job register for full details.