HETGS Line Profiles

Verification with Real HETG Dataset

Verification: Capella HETG/ACIS-S (ObsID: 1103) dataset

Finally we verify the validity of the LSF library with the real science dataset. In this example we use a 43 ksec Calibration/GTO observation of Capella (ObsID 1103) taken with Chandra HETG/ACIS-S.

Similar to the earlier validation, we use isis to perform line profile fitting (using a delta function) here. Since the Capella spectrum exhibits a weak continuum, we add a 1st order polynomial function to adjust the baseline.

Since the plots themselves speak a thousand word, please look at the fitting results shown in the following figures.

Line Profile Fitting:

Fe XVII $\bf{\lambda{15.015}}$

Figure 11: Results of line profile fitting at Fe XVII. A delta function (forward-folded with both RMF and ARF) is used to fit the line. The red line shows the best-fit model. The difference $\delta\chi$ is also displayed for your entertainment: (top) HEG; (bottom) MEG.

Mg XII $\bf{\lambda{8.421}}$

Figure 12: The same as for Figure 11.

Si XIII Triplet $\bf{\lambda\lambda{6.647, 6.685, 6.740}}$

Figure 13: The same as for Figure 11.

Fe XVII + Ne X Blend $\bf{\lambda\lambda{12.125, 12.136}}$

Figure 14: The same as for Figure 11.

These results of line fitting are quite representative of line profile analyses we have performed on other lines in the same dataset. A couple of spot checks on flux estimate also show that the measured fluxes do not depend on a full width that is used to extract line spectra here.

This demonstrates that the new LSF library is valid for extensive spectroscopic analysis.

Previous: Validation: Wavelength Next: MARX vs. ChaRT

This page was last updated Dec 4, 2002 by Bish K. Ishibashi. To comment on it or the material presented here, send email to bish (at) space.mit.edu.