Simulation of NGC 253

NGC 253 is a starburst galaxy containing diffuse, extended thermal emission and multiple point sources. As a first attempt to simulate this source, the SIS0 spectrum from a 6' region (composite diffuse + point source flux) was fit with a power-law plus gaussian lines model, providing a good fit (see figure). The source photons were then selected from a PSPC image (without background subtraction) assuming the power-law + lines spectrum for all photons. This crude approach produced an image similar to the actual observation, shown below. The exposure was 37 ks. A crude simulation of an Astro-E observations is also shown, created by improving the spatial resolution in the ASCA simulation by 3.75.

Actual ASCA PV SIS0 Observation
Simulated ASCA SIS0 Observation
Simulated Astro-E Observation (with an ASCA SIS detector)


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