What is the allowable range in Sersic index for the 'SER'-type objects?

Question

Hiya David, all,

Sorry to probably relay through you to Dustin again, but I think that by asking in an open forum (rather than via email) our Q&A will help more people :)

My current question is to do with the Sersic index that accompanies the morphology type ('PSF', 'EXP', 'REX', 'DEV', 'SER' [and 'DUP' for completeness]). It makes sense that the index is:

* set to 1 for 'EXP' and 'REX'

* set to 4 for 'DEV'

Q1) With respect to 'SER', is the range in Sersic index 0.5 to 6? (Judging from my crossmatched dataset.)

Q2) If the light profile for the 'PSF' is still in the form of r ^ -(1/n), then shouldn't the Sersic index for this morphology type be 'nan' rather than 0? Or '0' is more of a placeholder? (Or I've gotten my maths wrong.)

Best wishes,

Sarah

Comments

Please let me know if this question would be better-asked through https://help.desi.lbl.gov . Hope to hear from you soon.

Answer 1

I really think this is a better question for https://help.desi.lbl.gov. Although the Astro Data Lab hosts Legacy Survey data, the actual members of the Legacy Survey imaging team are mostly at other institutions. In addition, there is no reason you can't just ask Dustin Lang directly.

Comments

Hey Ben, yeah, I did subsequently ask Dustin via email on 16th June, but haven't heard back yet. Thanks for the reminder re: https://help.desi.lbl.gov -- I've posted my question there now