Notes on SEDs from BRC27

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First pass, september

  • 070349.6-112346 - we need to check the photometry for i2, i3, i4 - either i2 is low or i3 is high, or i3+i4 are both a little high. If this is a YSO, it is a very low excess, probably not significant.
  • 070349.8-112822 - Shevchenko 88 - no IR excess.
  • 070351.1-112054 - yuk. drop.
  • 070352.2-112100 - Chauhan 109 - disjoint, problem child. extended emission at 2mass bands, that could be affecting photometry at all bands. could also be intrinsic variability. Need to chase down missing photometry at one of the irac bands
  • 070352.7-112313 - ogura 2/chauhan 81 - no IR excess.
  • 070352.7-112416 - drop
  • 070353.2-112403 - ogura 3 - nice little YSO. double-check i3i4 phot to be sure.
  • 070353.5-112350 - shev 90 - bright star, likely early type (check lit tables), POSSIBLE excess at i3i4
  • 070352.7-112428 - ogura 4/chauhan 82 - check i3i4 photometry
  • 070354.4-112829 - shev 92/gregorio 69 - also bright early type, only i2i4 data. prob no excess.
  • 070354.6-112011 - chauhan 108 - one of hte problem children. disjoint. extended emission. can we resolve into two sources? if this resolved in 2mass, we should be able to resolve it in irac; need to chase photmetry.
  • 070354.9-112514 - ogura5 - why only 3 bands of irac - chase that photometry, prob no excess?
  • 070355.7-112931 - gregorio71 - no excess. not a lot of data either.
  • 070357.1-112432 - ogura 7 - nice disk
  • 070358.4-112325 - check i3 photometry. without that point, could be a nice SED.
  • 070359.7-112309 - ditch it
  • 070400.7-112323 - nice little SED, high Av in JHK points, strong disk at m24, but could worry abotu source confusion (e.g., more stars than just one in the mips beam). check images for contaminating sources.
  • 070401.2-112531 - nice little SED
  • 070401.2-112242 - check irac photometry.
  • 070401.2-112233 - nice little sed
  • 070401.3-112334 - greg74 - really nice SED, check i3
  • 070401.6-112406 - go look in the images - i think this may be a galaxy. go check irac photometry too.
  • 070401.6-112132 - check irac 3 photometry - nice
  • 070402.1-112512 - check all irac bands
  • 070402.2-112542 - this is a galaxy - 8 um point is high, and it's a flat sed. check the images to be sure, but my guess is it's a QSO.
  • 070402.3-112539 - little bit of excess, very bright,
  • 070402.7-112325 - probably a galaxy. check images.
  • 070402.9-112337 - ogura8+9 - nice SED.
  • 070403.0-112350 - ogura10 - check i3, nice SED
  • 070403.1-112327 - chauhan 107 - one of our problem children with extended emission in 2mass.
  • 070403.9-112609 - shev102 - bright obj, slight IR excess if at all.
  • 070403.9-112326 - check i3, could be a nice one
  • 070404.2-112355 - ogura12/chauhan86 - nice one
  • 070404.5-112555 - ogura13 - i wish we had 2 more points. no disk?
  • 070404.7-112339 - ogura 14 - check i3
  • 070404.9-112245 - drop
  • 070405.1-112313 - ogura15/chauhan 88 - nice
  • 070405.5-112337 - check irac photom all bands - iffy. likely bad photometry
  • 070405.6-112354 - drop?? check for why no 2mass, is in the catalog but with bad photqual flags.
  • 070405.7-112123 - check i3 phot. icky otherwise.
  • 070405.9-112209 - drop
  • 070405.9-112358 - ogura 16 - nice one!
  • 070406.0-112315 - ogura 17 - nice one. check i3.
  • 070406.4-112336 - ogura 18 - nice one. check i3
  • 070406.5-112227 - yeah, could be - check i3i4
  • 070406.5-112128 - icky, drop
  • 070406.5-112316 - ogura 19 - nice one. check i3i4
  • 070407.9-112311 - ogura 21: - icky? check photometry - make sure that there is good photometry actually of this source.
  • 070408.0-112354 - ogura 22 - nice one. worry about src conf m24
  • 070408.1-112313 - ogura 21+23: - icky? check photometry - make sure that there is good photometry actually of this source.
  • 070408.1-112309 - ogura 23:, chauhan 98 - check photometry - make sure that there is good photometry actually of this source. only 2 two mass, what happened to 3rd.
  • 070409.9-112316 - wiram23/ogura25/chau100 - nice one
  • 070411.2-111647 - greg78 - only 2 bands irac but looks like there might be a disk. chekc photom.
  • 070413.2-111900 - shev 111/greg 81 - nice sed with one opt point off maybe source mismatch, or extended emission or legitimate variability given that the other points line up.


  • check that i copied the cross ids into this file correctly... i was working as we talked, so it might be wrong! (Done 11/9, LMR)
  • check photometry for the ones that need checking (Done by the whole team, 11/9)
  • check images for the ones that need checking
  • compare this list to our problem children from before - any of the problem children on the old list not identified as such here too? (Done by Chelen, october)
  • decide out of this assessment which ones are being dropped for sure and being kept for sure
  • chase the 3 deep in bright nebulosity for which there are only 2 bands of irac data and for which there are not irac phot in the catalog. can we get viable phot out? are they disky ysos?
  • see if we can add WISE photometry to any object, especially those known YSOs with only partial IRAC coverage. (partially done, LMR, 29 sep)
  • count up number of objects in which bins: rediscovered as having ir excess, newly discovered as having IR excess, checked and noted as not having IR excess, dropped because we think they're galaxies, and dropped for bad phot (for our records, in case anyone asks)
  • make color-color and color mag plots of these groupings of objects. are they in the 'right' regions of the diagrams?
  • look at locations on the images of these groupings of objects. are they in 'good' regions of sky? (are YSO candidates near nebulosity, for example, and galaxies far away from it?)
  • fit slopes to SED to obtain classes, and count up ones in each bin (0, I, flat, II, III) (john's made headway on this)
  • possibly obtain and add optical data
  • if/when more optical data, go back through and reassess SEDs for feasibility in this same vein
  • if/when more optical data, make more color mag and color color plots to assess for viability.

repeat for BRC 34 ...

second pass, 10 Nov

  • 070349.6-112346 - with the new and improved i3, it no longer shows up as having an IR excess. this is not a previously known YSO candidate --> DROP THIS
  • 070349.8-112822 - Shevchenko 88 - no IR excess. Keep because previously known.
  • 070351.1-112054 - still drop.
  • 070352.2-112100 - Chauhan 109 - problem child - extended emission at 2mass bands. Oregon notes: "i3 difficult, i4 little blob, but I don’t think the photometry is reasonable". Florida only contributors to i4 flux. Large dispersion in i3 measurements from all of us. Took average of FL,OR,MN for i3, FL for i4 (with a large error). WISE is undoubtedly subject to the same issues. Need to spend some more time thinking about what is going on here.
  • 070352.7-112313 - ogura 2/chauhan 81 - no IR excess. Notes from group xls: "i4 very low and difficult to extract." no one reported i4 values; two (OR, MN) reported i3 values. took average of i3 values, with very large error bar. Possibly this should be converted to a limit, not clear. Definitely no excess, though. Keep because previously known YSO.
  • 070352.7-112416 - still drop
  • 070353.2-112403 - ogura 3 - took average of reported redone values for i3i4. IR excess still there, though low.
  • 070353.5-112350 - shevcheko 90 - possible problem child - bright star, type A0 in the literature. before, noted there might have been a small exess i3i4; took average of your new values, now clear no excess. keep because previously known. notes from xls: "Lots of extra light from nearby star in annulus in i1 & i2" but it's doing ok -- look at the SED. so it can't be too contaminated!
  • 070352.7-112428 - ogura 4/chauhan 82 - i3i4 was high before. took average of reported redone values for i3i4. i3 changed a lot, i4 not so much. This thing *may* have a small excess at i4.
  • 070354.4-112829 - shev 92/gregorio 69 - also bright, type B2 in the literature, only i2i4 data. prob no excess. NOT IN GROUP XLS! but off edge of main map, so the two channels we have already are likely to be all we have. ok as is. Keep because previously known YSO.
  • 070354.6-112011 - chauhan 108 - problem child - extended emission. xls notes: "added i3 but looks incorrect." indeed, the reported new photom at i3 are all over the place, and no one reported anything for i4. average of your reported values for i3 suggests disk. I redid the photometry myself at this location, and it may have a small disk, or the photometry may just be too hard to obtain. Large error bars on i4!
  • 070354.9-112514 - ogura 5/chauhan 94 - why only 3 bands of irac - chase that photometry, prob no excess? NOT IN XLS. I went and chased the photometry. may have a small disk at i4.
  • 070355.7-112931 - gregorio 71 - no excess. not a lot of data either. what's going on there? NOT IN XLS. object is NOT in region covered by all 4 bands; what we have is all we're going to get.
  • 070357.1-112432 - ogura 7/chauhan 83 - nice disk NOT IN XLS but phot is just fine.
  • 070358.4-112325 - original notes say: "check i3 photometry. without that point, could be a nice SED.". XLS has wrong crossid, and says that i don't have an i3 value for this guy, but i do - it's in the original SEDs. chased i3 photometry myself; new value pulls it right into line, and this thing does have a small disk.
  • 070359.7-112309 - still drop
  • 070400.7-112323 - original notes say: "nice little SED, high Av in JHK points, strong disk at m24, but could worry abotu source confusion (e.g., more stars than just one in the mips beam). check images for contaminating sources." The source in the images is relatively clean and bright, so source confusion is not a huge issue. WISE phot suggests some confusion in the beam, but there is bright ISM here. xls has wrong crossids, wrong phot -- says i have no i4, and i did, and the team's values are all wildly different than what is listed as coming from me, like an order of magnitude different. However, the team's recalculated values seem to match what i really do have for this source, so that's good -- you guys keyed off the RA/Dec rather than the names, which is really good!
  • 070401.2-112531 - nice little SED, no recalc needed
  • 070401.2-112242 - WISE points suggest source confusion; ISM is bright here. IRAC phot in xls is all pretty self-consistent, and doesn't agree with what is listed for me, but my guess is (as for the earlier one), the values listed for me are probably wrong. Checked image for source confusion, and it's actually pretty clean, and it is clearly there in the mips frame too, even though it wasn't in the catalog originally like that -- OR noticed this and reported a MIPS flux too. Redid IRAC phot, and MIPS phot. OR's MIPS flux is quite a bit high compared to what I get -- did you change the px scale appropriately in APT?
  • 070401.2-112233 - a Chauhan-anon source - nice little sed, no redoing needed.
  • 070401.3-112334 - Gregorio74,Chauhan-anon - problem child because 2mass phot may be bad - really nice SED, redid i3 and it falls back into line. 2mass is ok.
  • 070401.6-112406 - original notes said "go look in the images - i think this may be a galaxy. go check irac photometry too." Looking in the images, this is definitely NOT a galaxy, but there is complicated emission here. Notes in xls say this too. redone i3 phot falls into line nicely.
  • 070401.6-112132 - redone irac phot falls better into line. really not there in our MIPS image, so the WISE stuff is definitely not real, but instead source confusion with the nebulosity (our MIPS data are deeper than the WISE data, so if MIPS didn't see it, WISE shouldn't either, at least at 24 um). To make that point, getting a MIPS 24 upper limit from our data. The 3sigma limit (industry standard - review your basic statistics to remind yourself why) is just a little under the WISE point, further indicating how bright the ISM is here.
  • 070402.1-112512 - OR notes IRAC still doesn't match 2MASS and they added a MIPS detection. I agree, the IRAC, while it moves a little, does not fix the apparent discontinuity between 2MASS and IRAC. Looking in finder chart, faint and fuzzy in 2MASS, so that's probably why. Seems clean enough in Spitzer. At M24-- Hm, good eyes! I think you're right, there *might* be something there in the MIPS image, but it is DARN faint. I get something that is about 20% different in flux density.
  • 070402.2-112542 - original notes say "this is a galaxy - 8 um point is high, and it's a flat sed. check the images to be sure, but my guess is it's a QSO." BUT in looking at the images, it's too bright (far too bright) to be a QSO. Resurrect this one. XLS notes say "mixed sources 25 and 26" but I am not sure exactly what this means -- 25 and 26 by what numbering scheme? The PSF does look somewhat complex, but the bright 'source' you see just south of it (below it in instrument coordinates) i4 is suspisciously like a latent (e.g., an afterimage on the array). The 2mass images do suggest that there is more than one source here. I did photometry on the short i4 frame, and the long i3 frame, and the SED changed a little. It still is a seriously goofy-looking SED, and based on the SED alone, I would be very reluctant to keep this one. See discussion next item.
  • 070402.3-112539 - Shevchenko99,Gregorio75 - problem child - this one is tagged as a problem child in my notes (though not the xls because it has the wrong crossids) - original notes say "little bit of excess, very bright". This also has the xls notes about mixed sources, so probably the notes meant that the previous source and this one are very close, and indeed they are -- it is the adjacent source in the 2MASS images. The original SED for this one is a lot cleaner than the previous one, which is a little odd -- if they are influencing each other's photometry, they both should be bad, unless one is a lot brighter than the other. J=10.4 here, and the prior one's J is 11.3. this one's [3.6]=9.06 and the other one's [3.6]=8.38, so not hugely different. Not sure what is going on here. Original photometry at i3i4 was missing; adding it in here. Indeed, photometry likely compromised by nearby star. Will likely have to hand-process this using PSF subtraction in order to separate these two.
  • 070402.7-112325 - original notes say "probably a galaxy. check images." In image, deep in nebulosity, and close to 070403.1-112327, though not nearly as close as the prior pair. Sources seem clean in i1i2i3, but fuzzy and offset(?!) in i4, suggesting that photometry is not going to be terribly reliable. It's unlikely to be a galaxy, in any case. Both sources are seen in M24, though this one appears to have gotten allocated all of the M24 flux in the catalog. Fixing photom i3i4m1.
  • 070402.9-112337 - ogura8+9/Chauhan84 - problem child - nice SED. leaving as is. xls notes: "is this really one star?" no, it's both ogura 8 and 9. see images and discussion here.
  • 070403.0-112350 - ogura10/chauhan85 - nice SED. fixing i3. i2 now looks low, but it's actually right.
  • 070403.1-112327 - chauhan 107 - problem child - extended emission in 2mass. optical also disjoint. OR reports MIPS-24 but that it's tough photometry. This one is the one that is next to 070402.7-112325 above, and it is also embedded in fuzzy stuff. there should be a legitimate m24 detection associated with this, for sure. fixing i3i4m1. wise is confused by big beam and extended emission.
  • 070403.9-112609 - shev102 - bright obj, no IR excess. no type either for it.
  • 070403.9-112326 - original notes said "check i3, could be a nice one". i3 didn't change much; i4 changed a lot, and i2 changed a little. Object is in some nebulosity, faint at i4. would like to see what it looks like in optical. SED is steep.
  • 070404.2-112355 - ogura12/chauhan86 - nice one - no changes
  • 070404.5-112555 - ogura13 - orginal notes say "i wish we had 2 more points. no disk?" dunno why it didn't have data for other two channels orignally. xls notes say i4 very faint; indeed images show quite faint i3i4.
  • 070404.7-112339 - ogura 14/chauhan87 - xls notes say all 4 irac different, added m1. VERY faint in m1! i get that i1i2 are the same (maybe this was a mismatch problem in the xls?) and i3i4 different. adding m1, for sure. WISE is confused, again.
  • 070404.9-112245 - still drop
  • 070405.1-112313 - ogura15/chauhan 88 - nice, no changes. WISE is confused, again.
  • 070405.5-112337 - original note says "check irac photom all bands - iffy. likely bad photometry." indeed horrifically faint i3i4. xls notes agree. Redone photometry has ridiculous errors. --> DROP THIS as not likely real.
  • 070405.6-112354 - original notes say "drop?? check for why no 2mass, is it in the catalog but with bad photqual flags?" searching 2mass catalog, it's definitely not there. in the 2mass images, it's a very faint blip, consistent with background noise. this is off the edge of the BRC, starting to get into more liklihood that it is background AGN. redone i3 brings that into line. still quite worrisome that no JHK. will be interesting to see if there are optical data to go with this one. still a "drop??" -- keep for now. xls notes say i3i4 faint.
  • 070405.7-112123 - still just so-so. still a "drop??", keep for now, wait for optical.
  • 070405.9-112209 - drop (still)
  • 070405.9-112358 - ogura 16/chauhan89 - nice one! (still), no changes, WISE confused.
  • 070406.0-112315 - ogura 17/chauhan90 - fixed i3.
  • 070406.4-112336 - ogura 18/chauhan91 - fixed i3
  • 070406.5-112227 - very uncertain. fixed i3. now actually IRx goes away.
  • 070406.5-112128 - still drop. there for sure 2mass, i1i2, but then garbage i3i4.
  • 070406.5-112316 - ogura 19/chauhan92 - nice one. fixed i3i4
  • 070408.0-112354 - ogura 22/chauhan97 - OUT OF ORDER because next trio need to go together. original notes say "worry about src conf m24". on edge of map. is worrisome to only have excess at m24. dunno. keep because known yso.
  • 070407.9-112311 - ogura 21: - problem child - wise source matches here, but removing those points since it is clearly confused.
  • 070408.1-112313 - ogura 21+23: - problem child -
  • 070408.1-112309 - ogura 23:/chauhan 98 - problem child - only 2 two mass, what happened to 3rd.
  • 070409.9-112316 - wiram23/ogura25/chau100 - nice one, no changes
  • 070411.2-111647 - greg78 - only 2 bands irac possible. wise helps but may be confused.
  • 070413.2-111900 - shev 111/greg 81 - problem child - nice sed with one opt point off, maybe source mismatch, or extended emission or legitimate variability given that the other points line up. wise helps but may be confused. 'improved' i3 point suggests wise is confused.

Off the problem child list - Gregorio 76 (wasn't in catalog), Shevchenko 107 (wasn't in catalog), and Shevchenko 111=Gregorio81 (last one above) are all part of some bright nebulosity, in regions where we only have 2 bands of IRAC. The first two may be hard to tie to individual sources, as the region is bright and complex. As long as I'm in the mode of patching flux densities, I went ahead and did these too.

  • 070406.5-111835 - Gregorio76 - optical and WISE both contaminated by bright emission. disky, probably.
  • 070407.5-111857 - Shev107 - no 2 mass match because photometry tagged as crappy (went and got and stuffed back in with larger errors), and WISE also most likely still confused.

OK! so now, making a new catalog with the whole batch.

Notes from 13 Dec

looking at location in images. pretty happy with rejects. 070349.6-112346 seems to be a legitimate source, ah, but with a really small excess. nevermind. happy to drop this one. what about the bright source near 07:03:54 -11:23:42? ah, it has no excess to speak of. could still be a member, but we can't tell from the data we have.

locations in CMDs look pretty good. lots of low-excess sources from known YSO sample, makes plots look odd. would really like to see the optical CMD!!