High Energy Astrophysics -
Fall
2006
Homework #3 - due September 26
1. Using ADS, find a paper using Chandra observations to study a topic
of interest to you. Write a short summary (1 page) explaining why
the
paper is interesting, the instrument used on Chandra, the results
obtained, and the
implications of those results. Be sure to include the title,
first author, and journal reference for the paper.
2. Using a plotting program of your choice, plot the surface density,
temperature, and energy dissipation rate versus radius of a disk
surrounding a black hole. Be sure to choose suitable
dimensionless units for all four quantities. Cover a radius range
of 0 to 100 ri.
3. Download the data for ObsID 4555, an observation of the
ultraluminous X-ray source in NGC 5408. Extract a spectrum and
create response matrices. Fit the spectrum in the 0.3-8 keV band
using a model consisting of the sum of a power-law and a multicolor
disk blackbody with interstellar absorption. Hand in a plot of
your data and best fit along with the best fit parameters with errors
and an estimate of the flux.