Plot single page the template star spectra

AS5001 (SUPAAAA) Advanced (Astronomical) Data Analysis Project 2 —– Due Wed 28 Nov 2018.

Hunting a Black Hole in GS2000

The techniques required have been developed in the lectures and homework sets. Steps of the cross-correlation radial velocity analysis may be as follows:

1. Plot on a single page the template star spectra, arranged by spectral type, and normalised to a common continuum level, to show how absorption line ratios change with spectral type. [5]

(a) Subtract the continuum from the GS2000 spectrum, and from the template spectra.

(b) Apply a velocity shift to the continuum-subtracted template spectrum.

6. Plot the measured velocities and 1-sigma uncertainties as a function of binary phase. Put these results also in a table in your report. [5]

7. Fit a sinusoidal velocity curve of the form

9. Give two expressions for the compact object mass function f(Mx), the first in terms of the observable quantities P and K, and the second in terms of the compact object mass Mx, the inclination i, and the mass ratio q = Mc/Mx, where Mc is the companion star mass. From the binary period P and your measured K velocity, estimate f(Mx) in solar units. Give also the 1-sigma uncertainty. [5]

10. Adopt a specific inclination i = 90◦, and a specific Mc = 0.5 M⊙. For these choices, calculate the compact object mass Mx. Give the 1-σ uncertainty, assuming that i and Mc are known exactly. Be clear about your algorithm for estimating the uncertainties, and collect your results in a table in your report. [5]