What are the bumps in this spectrum?

by JeanTate

The galaxy is AGS000018i (DR7 ObjId 588015509820801199), the DR9 PNG spectrum is at:
http://skyserver.sdss3.org/dr9/en/get/specById.asp?id=1753154303440218112

What are the bumps/humps in the continuum, at ~528nm (range ~522-535), ~619nm (~599-632), ~671nm (~667-684)? The "best fit" in the interactive spectrum (here) doesn't.

enter image description here

In QS this galaxy has a log(mass) of -1; does the poor continuum fit explain this (at least partly)?

Posted August 8, 2013 10:40 PM

by JeanTate

Actually, this galaxy is an outlier! V_disp is 850±-3. Also, the Hbeta flux may be messed up by being 'on top of' the sky line.

Posted August 9, 2013 12:43 AM

by JeanTate

AGS00001nu (587738615943725169) has two not-in-best-fit' bumps/humps, at approx the same (rest frame) wavelengths (the third, just blue-ward of the HeI line, is not present). In addition, the 4000Å break fit is poor.
Spectrum link: http://skyserver.sdss3.org/dr9/en/get/specById.asp?id=2191009522632386560

enter image description here

Oh, and V_disp for this galaxy is also 850±-3! 😮

Posted August 9, 2013 1:14 AM

by JeanTate

AGS00000an has a spectrum with similar features (mlpeck posted this in the Outliers thread, see that post for more details):

enter image description here

UPDATE: this is a supernova

Posted August 9, 2013 1:18 AM

by JeanTate

AGS00001xe (587741602030551154) also has two strange bumps, this time between Hgamma and Hdelta, and between Hdelta and the H&K lines. The 'best fit' misses these, and it also quite a ways off in the UV (blue-ward of [OII]); spectrum, interactive:

enter image description here

Posted August 12, 2013 2:07 AM