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The HEASARC and NuSTAR teams are greatly saddened by the sudden passing of Katja Pottschmidt. Most recently Katja was the lead scientist for the NuSTAR Guest Observer Facility (GOF), a role she had supported for many years. During her science career she worked on many other high energy astrophysics missions and played an integral role in advancing our knowledge of the universe. She was a wonderful colleague and friend and will be keenly missed by all who knew her.

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cosmo

set the cosmology

Set the cosmology used (i.e., $H_0$, $q_0$, and $\Lambda_0$).

Syntax: cosmo <$H_0$><$q_0$><$\Lambda_0$>

where <$H_0$> is the Hubble constant in km/s/Mpc, <$q_0$> is the deceleration parameter, and <$\Lambda_0$> is the cosmological constant. If the cosmological constant is non-zero then at present XSPEC requires that the universe is flat. In this case the value of <$q_0$> will be ignored and XSPEC will assume that $\Omega_{matter}\geq 1-\Lambda_0$. The default values are <$H_0$> = 70, <$q_0$> = 0.0, and <$\Lambda_0$> = 0.73

Examples:

XSPEC12>cosmo 100
// Set <$H_0$>= 100 km/s/Mpc
XSPEC12>cosmo ,0
// Set <$q_0$>= 0
XSPEC12>cosmo „0.7
// Set a flat universe with <$\Lambda_0$>= 0.7