BRC Spring work

Big Picture

We need to come up with a short list of papers to read in detail and discuss. We'll rotate through our short list of papers, and each of you will get one to present to the group. This is modelling a so-called "journal club", a common occurrence in astronomy departments/groups/centers, where the papers are usually selected out of recent astro-ph mailings.

Papers to discuss

Type in your paper suggestions here....

Luisa nominates - either this one (IC2118, from my original teacher team), or the one I am in the process of finishing writing on CG4 from my team last year. The reason for this is because the analysis we will do for our BRCs is very similar to the analysis we did for IC2118 or CG4.

Chelen's nominees - reading the IC2118 and/or the CG4 paper would be good ways to learn the analysis procedure we're going to use/modify/manipulate. I also think a couple of papers on BRCs would be helpful for background information. Here's the bibliography from our proposal (with my comments) --CJohnson 09:55, 23 March 2011 (PDT)

paper	Chelen's notes	Luisa's notes	presenter/ present with
Guieu, S., et al., 2010, ApJ, 720, 46 (pdf)		the 2118 paper (from my first teacher team).... because our work will look a lot like this	3/30, BY MARCELLA
Ogura K., Sugitani K., Pickles A., 2002, AJ, 123, 2597.	Optical + 2MASS; contains general info of BRCs	Most recent of the Sugitani series of four. Using Halpha to look for YSOs, following up their other work. relevant issues: using multiple wavelengths to find YSOs (see Finding cluster members), spatial resolution (see Resolution), caveats with finding candidates. Nice intro, summary of larger issues, discussion of results. Need to be sure that this catalog is included in our list of previously known YSOs in this region, compare our results to theirs. Finding charts helpfully included so we can match obj. We should discuss this one. Maybe not the other Sugitanis, but if we do discuss the other Sugitanis ("Group S") then they should be combined here.	do this, possibly with rest of group S TO BE DISCUSSED 4/20 BY DIANE
Sugitani K., Fukui Y., Ogura K., 1991, ApJS, 77, 59.	SFO article to which many other articles refer ... might be worth a review??	the original SFO, origin of "BRC" terminology, numbers 1-44. covers the northern hemisphere. has nice intro/summary of what's going on in BRCs, CGs, etc. Nice approach of combining two large surveys -- POSS and IRAS; nice clear discussion of weed-down process. Second half of paper (detailed analysis of IRAS colors, etc.) obsolete but has same essence as what we do now. If we do this one, recommend review with other Sugitani, Ogura papers.	drop? else w/ group S 1991
Sugitani K., Ogura K., 1994, ApJS, 92, 163.	another survey	SFO/BRC catalog/nomenclature continued into the southern hemisphere. (NB: all our obj are in the N. Hem paper!). SFO/BRC numbers 45-89. Second in the Sugitani series. Again, much of detailed analysis now obsolete. If we do this one, recommend review with other Sugitani, Ogura papers.	drop? else w/ group S 1994
Sugitani K., Tamura M., Ogura K., 1995, ApJ, 455, L39.	IRAS survey	JHK follow-up of IRAS sources from SFO. relevant issues: using multiple wavelengths to find YSOs (see Finding cluster members), spatial resolution (see Resolution). Shame on them for not publishing a data table or even a figure with the locations of everything they identify as a YSO! BRC 27 is one that they choose to include in a finder chart, but doesn't do us much good. Nice summary of larger issues, timescales. Short paper. If we do this one, recommend review with other Sugitani, Ogura papers.	drop? else w/ group S 1995
Morgan L. K., Thompson M. A., Urquhart J. S., White G. J., Mio J., 2004, A&A, 426, 535. note has erratum too.	Radio and mid-ir survey	NRAO/NVSS/VLA (20cm), DSS, MSX data. both 27 and 34 in here, though 34 is a non-det. nice intro to the physics, though they get into far more math than we need to. relevant issues: this radio is thermal (free-free emission). they smoothed data -- spatial resolution (see Resolution). another nice use of three big surveys. sfo 27 in the online-only fig 1. T3 also online only. identifying ionizing source is not the same as identifying point sources in the images themselves. it's not clear that this is all that relevant for us. part of a PhD thesis.	Drop? if do, do with "Group M" but skip the math. 2004 TO BE DISCUSSED 4/27 BY CHELEN
Morgan L. K., Thompson M. A., Urquhart J. S., White G. J., 2008, A&A, 477, 557.	SCUBA survey	SCUBA submm survey (450+850 um) plus IRAS (12, 25, 60, 100 um), MSX, and 2MASS (erroneously identified as 2mm but really 2 micron). both 27 and 34 in here. next part of a PhD thesis. lots of nice overview, summary (as would be expected for a thesis) spread throughout article. seems to be a really long paper, but is almost all figures in the appendix. relevant issues: how the objects they are talking about (at long and short wavelengths) compare to what we see in our images (see Resolution and their, e.g., fig 4). Forward reference to Spitzer data analysis like ours but then says have already looked for GLIMPSE, 24 um obs. They are only looking at low-res flux densities. Appendix may be useful for scavenging additional targets if we want to do more analysis on more targets.	Probably the most worth doing of "Group M"; skip the math. 2008
Morgan L. K., Urquhart J. S., Thompson M. A., 2009, MNRAS, 400, 1726.	Radio, mid-ir, SCUBA observations; redefined SFO catalog	JCMT (CO) observations. both 27 and 34 in here. 22 arcsec resolution! (see Resolution and their fig 2 here.) Likely last of his thesis, or first of his postdoc. (Look, his address changed, so this was published while he was a postdoc, but it's the same collaborators as before at his old institution, so my guess it's leftover thesis work.) They think 27 has been triggered, 34 not; this provides a nice compare-and-contrast opportunity for our write-up. Quick read.	Do with "Group M" for fig 2. 2009
Chauhan N, Pandey A.K., Ogura K., Ojha D.K., Bhatt B.C., Ghosh S.K., Rawat P.S., 2009, MNRAS, 396, 964.	Tests S4F theory; survey using Spitzer archival data; not deep enough??	BRC27. Optical (BVIc)+2mass+spitzer/irac. yes, this one we should spend considerable time on. Testing small-scale sequential star formation suggested in earlier 'group S' papers. references 'group M' papers, so do this one after those, and right before CG4 for contrast in methods. nice intro. multiwavelength and contaminants (see Finding cluster members). As I read this, they are using optical+nir to pick their YSOs, not Spitzer-driven. Whoever is presenting this needs to assess this in detail. We will find a different set of obj, not just classify them differently. Note lots of information is online only, which i attached to article pdf. analysis of Halpha-age and mass function is a bit of overinterpretation IMHO. need spectroscopy first!!	do second to last. read closely! compare to everything above. TO BE DISCUSSED 5/11 BY JOHN
Rebull, L., et al., 2011, AJ, in press (CG4 paper)	do as last review before we get started on ours?	this is very close to our analysis, though we may not have any optical at all.	discuss last, since methodology very similar? TO BE DISCUSSED 5/18 BY MARK Powerpoint presentation giving at GISS 2011 summarizing the NITARP 2010 paper "New Young Star Candidates in CG4 and Sa101", Rebull et all, 2011 File:GISS 2011 Legassie gum nebula.pptx
		this line separates the "should dos" from the "maybe skips"
Gregorio-Hetem J., Montmerle T., Rodrigues C. V., Marciotto E., Preibisch T., Zinnecker H., 2009, A&A, 2009, 506, 711.	X-ray survey of CMa region	BRC 27. ROSAT+VRI data. relevant issues: using multiple wavelengths to find YSOs (see Finding cluster members), spatial resolution (see Resolution). Mentions Chandra, XMM data, both of which would cover BRC 27, but I can't find the subsequent analysis that they advertise. We need to include this catalog in what we accumulate, and compare our results to theirs. Not clear if we need to actually discuss it or not.	need someone to scavenge data, maybe not discuss?
Shevchenko V. S., Ezhkova O. V., Ibrahimov M. A., van den Ancker M. E., Tjin A, Djie H. R. E., 1999, MNRAS, 310, 210.	Optical catalog that includes both BRC 27 and BRC 34; contains general info on BRCs	BRC 27 only. optical. age, distance estimate. photoelectric UBVR(!) and objective prism spectroscopy for Halpha and spectral types. combined with IRAS. using multiple wavelengths to find YSOs (see Finding cluster members). We need to include this catalog in what we accumulate, and compare our results to theirs. This is not necessarily a trivial task, as they have photographic 1950 coordinates, which will need to be precessed and then matched to a 2mass source to get a more recent position estimate (they have finding charts, which should help), but it only needs to be done for the objects in our field of view (our data). Not clear if we need to actually discuss it or not. It's old methodology (from an Uzbecki telescope), but good stuff, especially the spectral types. nice "put-it-in-context" discussion at the top for the entire CMa R1 region.	need someone to scavenge data, maybe not discuss?
Wiramihardja S.D., Kogure T., Nakano M., Yoshida S., 1986, PASJ, 38, 395.	Optical survey of CMa region	BRC 27. Halpha plus photographic UBV.(!) using multiple wavelengths to find YSOs (see Finding cluster members). We need to include this catalog in what we accumulate, and compare our results to theirs. This is not necessarily a trivial task, as they have photographic 1950 coordinates, which will need to be precessed and then matched to a 2mass source to get a more recent position estimate (they say they have finding charts, which should help), but it only needs to be done for the objects in our field of view (our data). Nice cross matching that they've already done for their previously identified objects. Not clear if we need to actually discuss it or not. It's a really old paper.	need someone to scavenge data, maybe not discuss?
Soares J.B., Bica E., 2002, A&A, 388, 172.	2MASS obs of BRC 27	BRC 27. 2MASS. Editing ghastly. Really simple paper. In theory, we should include their results in what we accumulate, and compare our results, though (a) they are using "prehistoric" 2mass data reduction, and (b) they really make it hard, as they don't even tell us how many YSOs they think they've found, just the numbers of objects for which they've done photometry. So I don't think we really can compare our results to this one. However, nice "put it in larger context" discussion with wide-field IRAS image.	skip it unless you want to see the IRAS image.
Soares J.B., Bica E., 2003, A&A, 404, 217.	2MASS + optical survey	Simple paper elsewhere in the same cloud as BRC 27. Same sort of 2MASS analysis as their 2002 paper. Still archaic 2MASS data reduction. Skip it.	skip it.
Valdettaro R., Palla F., Brand J., Cesaroni R., 2005, A&A, 443, 535.	Radio survey of water masers	22.2 GHz (=1.35 cm if I did my math right). Really nice intro summarizing the big picture. Following up on Morgan and similar work asserting high-mass stars forming in BRCs by looking for masers. Our objects observed, not detected. Finding lots of non-detections, suggesting that low-mass stars forming instead. Nice, short writeup of basically a non-result, and I think they've gotten the interpretation spot-on. Nice to at least scan after the Morgan stuff for context. larger issues: spatial resolution (see Resolution). Again!! :)	maybe skip?
Valdettaro R., Migenes V., Trinidad M.A., Brand J., Palla F., 2008, ApJ, 675, 1352.	VLA obs of water masers; BRC 34	more water masers, following up 2005 work. BRC 34 observed, not detected. nice intro that puts their work in context with the rest of what they've done. Lots more non-dets, interpreted as forming low mass and/or older stars than had been assumed. I think they've gotten the interpretation spot-on.	maybe skip?
Allen L., et al. 2011, American Astronomical Society, BAAS, 43, 258.15.	Poster from AAS ... good to review?	ok, but not a lot of content beyond the images and their 'big picture' work.	skip?
Makovoz D., Marleau F. R., 2005, PASP, 117, 1113.	MOPEX info	VERY technical, not a manual, and not all that terribly relevant to what we're doing. let's drop this one from the list.	(drop)

I second reading all of the bibliographic articles, plus the one on IC2118. My reasoning is that I think we should be familiar with all of the work for the references we cited, and I would like any preview of the work that we will do. The older articles I have been looking (Stromgren, 1948 & Sharpless 1959)at are interesting for their historical context, but probably not necessary for all of us to read. --Sartore 12:34, 23 March 2011 (PDT)

Literature known YSOs

NOTE: Make sure to read Identification of Previously Known Objects on Candidate List for much discussion from Fall 2011 about many of these lists!

In the end, we need a master file (text or xls) that has one line per object and all of the information (photometric plus any Ha measurements (usually in equivalent width)) we can gather on that object (along with the origin of that information). Papers in the literature might have rediscovered the same objects themselves, and we will certainly rediscover some of them ourselves. We need to be able to identify them as known objects when we find them.

We need to scavenge the papers for names, coordinates, and photometry, and then go update the coordinates using 2MASS. YouTube video on how to do this using the 2MASS archive. Guidelines:

• (a) watch the units of the coordinates (J2000 or B1950);
• (b) take the closest bright 2MASS source. As in, there should only be one 2MASS source near the target. If there is more than one, take the brighter one.
• (c) Make a note of the 2MASS name as well, but you don't have to write down all the JHK measurements too; I have automatically grabbed those and matched them to the Spitzer catalog. We're trying to get the updated coordinates so that I can automatically merge the old information with our new catalog.
• (d) Do only BRC 27 and 34. Don't do the rest!
• (e) More than one person (at least 2!) should independently work on each of these tables, because transcription errors are really easy to make.
• (f) During the time in which we are working on this, we can either keep one big master list with everything (which is what we will have in the end), or we can keep tables separately for each paper. If the individual tables have updated good coordinates, then we can have the computer merge them. But, this may mean that you look up the same objects more than once, since the same objects probably appear in more than one paper.
• (note: what do i mean by 'machine readable'? i mean a plain text file that the computer can read in and parse and understand coordinates, etc. PDF is not enough. plain text is what i need.)

The papers (links above), in order of priority:

• Ogura K., Sugitani K., Pickles A., 2002, AJ, 123, 2597. -- and see also File:Table5-edited.txt (19 May), which is the file i sent in which i was starting this process with their table 5. (this is what i was using in the youtube video above.) File:Ogura-table5-diane.txt (24 June)-- diane's version of the coordinates for both BRCs from table 5. from Luisa, 15 sep -- File:Ogura-luisa.txt
• Chauhan N, Pandey A.K., Ogura K., Ojha D.K., Bhatt B.C., Ghosh S.K., Rawat P.S., 2009, MNRAS, 396, 964. -- coordinates ok, just get a machine-readable version of the table so that we can make a note of the photometry. FROM LUISA (23 June): File:Chauhan-table3.txt and File:Chauhan-table6.txt -- important things to note: all plain text. no tabs. columns aligned. 'missing' data in the pdf version are also mising here. just brc27 (that's all we care about).: NOTE: DONE
• Gregorio-Hetem J., Montmerle T., Rodrigues C. V., Marciotto E., Preibisch T., Zinnecker H., 2009, A&A, 2009, 506, 711. -- coordinates are ok. just get machine-readable version of the main source table so that we can include the information from here. FROM LUISA (23 June): File:Gregoriohetem-tablea1.txt -- important things to note: all plain text. no tabs. columns aligned. annoying notes at bottom moved to last column. two-part table combined into one.: NOTE: DONE
• Shevchenko V. S., Ezhkova O. V., Ibrahimov M. A., van den Ancker M. E., Tjin A, Djie H. R. E., 1999, MNRAS, 310, 210. -- CAUTION, 1950 coords! need to be precessed and updated! Need also to check their finding charts against 2MASS to be sure you've found the right one. File:Shev-diane.txt (27 June) File:Shevchenko stellar.txt (28 June) --Sartore 08:26, 28 June 2011 (PDT) UPDATE from Luisa 14 Sep - I just noticed that this paper has an "online data" link in ADS which goes here. After a few clicks, you can get here which includes all the data tables from this paper. We care about Table 1, and the ReadMe file explains the contents of the file. Here (File:Fullshev.txt) is the data table (with a .txt extension), with the column heading definition from the ReadMe at the bottom of the file (sorry). Note that this is the entire table as published, so it is still 1950 coordinates. I took this list, precessed the coordinates, bounced it against the 2MASS catalog, and compared it with the stuff you all had done before. I found several inconsistencies in the stuff noted before and above, added several stars, and noted several specifics about several objects. File:Shev-luisa.txt ... note that this has many columns, with occasional notes on the far right. Note too that I converted and copied the single-band photometric measurements and the spectral types into this file from the master table in the paper.
• Wiramihardja S.D., Kogure T., Nakano M., Yoshida S., 1986, PASJ, 38, 395. -- CAUTION, 1950 coords! need to be precessed and updated! Need also to check their finding charts against 2MASS to be sure you've found the right one. This was a listing of emission line stars in CMa, and only two of the emission line stars previously listed actually fall into the area assigned to BRC 27. The other entries are generally very close to the boundary in one dimension (or both), so I pulled them out of the original listing. File:Wira separated.txt--Sartore 08:17, 29 June 2011 (PDT) UPDATE 15 Sep, from Luisa: File:Fullwiram.txt is a transcription of the important information out of the original paper, just for the stars even vaguely in our region. File:Wiram-luisa.txt ... note that this has many columns (coordinates, photometry, and spectral types from the paper). The 2mass match as listed here has each been verified by at least one of you.

Merging of all these sources together.

• 10 AM JUNE 30 -- luisa's merging for BRC 27 of all the tables here. File:Luisa-mergedbrc27.txt IMPORTANT NOTES: (1) I have merged the tables as posted here (as opposed to as published in the paper). since some were assembled by hand (e.g., wiramihardja), not all the sources in the published table are included, but for other ones (e.g., gregorio), all of the published sources were easily scooped up and included, so sources well beyond our image boundaries are included here from some papers. (2) I retained more data than I printed back out here. I did this just to keep the size of this table manageable. The stuff as printed here is really the most important stuff for assessing youth and matches to literature. (3) the first column is an indication of whether or not i can find a match in our spitzer catalog, just to make it easier for you to refine your approach. (4) -9 means no data available, except for the Ha eqw, in which case -999 means no data. (4) the units of the coordinates are J2000. the units of the photometry (UBVRIc) are magnitudes. The units of loglx are log(luminosity in X-rays). The units of Haeqw are Angstroms. (5) since BRC 34 has only 2 sources from Ogura, I did not bother making a catalog like this for it -- it has essentially no supporting data. But both have matches in our Spitzer catalog.
• As of 4:50 pm Thursday 9/1, here is the best catalog i have : File:Litsrcs-brc27-0901-lmr.txt it still has a lot of problems; see Identification of Previously Known Objects on Candidate List...
• As of 15 Sep here is the best (final???) catalog I have: File:Litsrcs-brc27-0915-lmr.txt