J/ApJS/209/32 Probable young stars in the MYStIX project (Broos+, 2013)
Identifying young stars in massive star-forming regions for the MYStIX project.
Broos P.S., Getman K.V., Povich M.S., Feigelson E.D., Townsley L.K.,
Naylor T., Kuhn M.A., King R.R., Busk H.A.
<Astrophys. J. Suppl. Ser., 209, 32 (2013)>
=2013ApJS..209...32B 2013ApJS..209...32B
ADC_Keywords: Photometry, infrared ; X-ray sources ; YSOs ;
Cross identifications ; H II regions ; Clusters, open
Keywords: infrared: stars - methods: data analysis - methods: statistical -
open clusters and associations: general - stars: pre-main sequence -
X-rays: general - X-rays: stars
Abstract:
The Massive Young star-forming complex Study in Infrared and X-rays
(MYStIX) project requires samples of young stars that are likely
members of 20 nearby Galactic massive star-forming regions. Membership
is inferred from statistical classification of X-ray sources, from
detection of a robust infrared excess that is best explained by
circumstellar dust in a disk or infalling envelope and from published
spectral types that are unlikely to be found among field stars. We
present the MYStIX membership lists here, and describe in detail the
statistical classification of X-ray sources via a "Naive Bayes
Classifier."
Description:
The Massive Young star-forming complex Study in Infrared and X-rays
(MYStIX) project, described by Feigelson et al. (2013ApJS..209...26F 2013ApJS..209...26F),
seeks to identify and study samples of young stars in 20 nearby
(0.4<d<3.6kpc) Galactic massive star-forming regions (MSFRs). These
samples are derived using X-ray data from the Chandra X-ray
Observatory, near-infrared (NIR) photometry from the United Kingdom
InfraRed Telescope (UKIRT) and from the Two Micron All Sky Survey
(2MASS), mid-infrared (MIR) photometry from the Spitzer Space
Telescope, and published spectroscopically identified massive stars.
Our purpose here is to describe our efforts to minimize contaminants
in the MYStIX catalogs of young stars, which we refer to as "MYStIX
Probable Complex Members" (MPCMs), and to present the MPCM catalog for
each MYStIX MSFR. An MPCM catalog is the union of three sets of
probable members identified by three established methods for
identifying young stars (Feigelson et al. 2013ApJS..209...26F 2013ApJS..209...26F, Fig. 3).
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
reg.dat 22 20 List of the 20 nearby Galactic massive
star-forming regions; table added by CDS
mpcm.dat 971 31549 MPCM (MYStIX Probable Complex Members) sources
and properties (table 2)
table7.dat 491 25277 Counterparts to X-ray sources and classification
probabilities
refs.dat 97 42 References
--------------------------------------------------------------------------------
See also:
B/chandra : The Chandra Archive Log (CXC, 1999-2013)
B/mk : Catalogue of Stellar Spectral Classifications (Skiff, 2009-2013)
II/293 : GLIMPSE Source Catalog (I + II + 3D) (IPAC 2008)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
J/ApJS/209/31 : The MYStIX IR-Excess Source catalog (Povich+, 2013)
J/ApJS/209/30 : MYStIX: Bayesian matching (Naylor+, 2013)
J/ApJS/209/29 : MYStIX: MIR observations and catalogs (Kuhn+, 2013)
J/ApJS/209/28 : MYStIX Wide-Field NIR data: crowded fields (King+, 2013)
J/ApJS/209/27 : MYStIX: the Chandra X-ray sources (Kuhn+, 2013)
J/ApJS/194/14 : A Pan-Carina YSO catalog (Povich+, 2011)
J/ApJS/194/10 : NIR properties of YSO in the CCCP (Preibisch+, 2011)
J/ApJS/194/5 : Carina OB stars in the CCCP catalog (Gagne+, 2011)
J/ApJS/194/4 : Classification of CCCP X-ray sources (Broos+, 2011)
J/ApJS/194/2 : Chandra Carina Complex Project (CCCP) catalog (Broos+, 2011)
J/ApJ/714/L285 : YSO candidates in M17 SWex (Povich+, 2010)
J/ApJ/708/1760 : Flux estimations of faint X-ray sources (Getman+, 2010)
J/ApJ/696/1278 : The extended star-forming environment of M17 (Povich+, 2009)
J/MNRAS/384/675 : Monitoring low-mass stars in NGC 2362 (Irwin+ 2008)
J/ApJS/169/353 : Chandra sources in M17 (Broos+, 2007)
J/ApJS/168/100 : X-ray study of star-forming region NGC 6357 (Wang+, 2007)
J/ApJ/671/605 : NGC 2264 and ONC PMS stars in the infrared (Cieza+, 2007)
J/ApJ/642/972 : IR phot. of a star-forming core in NGC 2264 (Young+, 2006)
J/MNRAS/371/252 : Southern B and Be stars (Levenhagen+, 2006)
J/ApJS/160/353 : Membership of the Orion nebula population (Getman+, 2005)
J/ApJS/160/319 : COUP: observations and source lists (Getman+, 2005)
J/AJ/130/1145 : YSO near-infrared properties (Doppmann+, 2005)
J/ApJ/562/446 : X-rays and protostars in Trifid nebula (Rho+, 2001)
J/A+A/355/651 : HRI observations of PMS stars in NGC 2264 (Flaccomio+, 2000)
Byte-by-byte Description of file: reg.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 16 A16 --- Name MYStIX Galactic massive star-forming region
(MSFR) name
18- 22 A5 --- Reg Abbreviated region name
--------------------------------------------------------------------------------
Byte-by-byte Description of file: mpcm.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 16 A16 --- Reg MYStIX Galactic massive star-forming region
(MSFR) name
18- 35 A18 --- MPCM IAU source name (HHMMSS.ss+DDMMSS.s; J2000)
36 A1 --- m_MPCM [ab] Multiple MPCM name component (1)
38- 47 F10.6 deg RAdeg Right Ascension (J2000)
49- 58 F10.6 deg DEdeg Declination (J2000)
60- 64 F5.3 arcsec ePos [0/2.1]?=- 1σ error around (RA,DE)
66- 76 A11 --- rPos Origin of position (G1)
78- 95 A18 --- CXO X-ray source name in IAU format
(HHMMSS.s+DDMMSS; J2000)
97-107 A11 --- Xlab X-ray source name used within the MYStIX
project (G2)
109-126 A18 --- NName Name in NIR catalog (G3)
128-143 A16 --- Nlab Label in NIR catalog
145-162 A18 --- MName Name in MIR catalog
(HHMMSS.ss+DDMMSS.s; J2000 or NNNN) (G4)
164-192 A29 --- Mlab Label in MIR catalog
194-223 A30 --- Olab Label in OB catalog (2)
225-229 I5 --- Xind ?=-99 0-based index in X-ray catalog (Sec. 4)
231-234 I4 --- Iind ?=-99 0-based index in IR excess catalog
(Povich et al. 2013, Cat. J/ApJS/209/31)
236-265 A30 --- SpT MK spectral type
267-280 A14 --- r_SpT Reference for spectral type (3)
282-287 F6.3 mag OBmag [4.4/24.5]? Visual photometry in OB Catalog
289-291 A3 --- OBband Visual band for OBmag (J, K or V)
293-296 F4.2 --- pr.0 [0/1]? p-value for no-source hypothesis (4)(5)
298-301 F4.2 --- pr.1 [0/1]? p-value for single observation (4)(6)
303-306 F4.2 --- pr.m [0/1]? p-value for merged observations (4)(6)
308-316 F9.2 s t.exp ? Total exposure time in merged
observations (4)
318-321 F4.2 --- f.exp [0/1]? Fraction of "Exp" that source was
observed (4)(7)
323-325 I3 --- Nobs [1/9]?=-99 Total number of observations
extracted (4)
327-329 I3 --- Nph [1/9]?=-99 Number of observations merged to
estimate photometry properties (4)
331-336 F6.3 arcmin b_theta ? Smallest off-axis angle for merged
observations (4)
338-343 F6.3 arcmin theta ? Average off-axis angle θ for merged
observations (4)
345-350 F6.3 arcmin B_theta ? Largest off-axis angle for merged obs. (4)
352-355 F4.2 --- PSFf [0/1]? Average PSF fraction (at 1.5 keV) for
merged observations (4)
357-360 F4.2 --- aglow [0/1]? Suspected afterglow fraction (4)(8)
362-366 I5 ct Oct-t ?=-99 Extracted total (0.5-8keV) counts in
merged apertures (4)
368-375 F8.2 ct Nct-t [1/89438]? Net total (0.5-8keV) counts in
merged apertures (4)
377-384 F8.2 ct Nct-s ? Net soft (0.5-2 keV) counts in merged
apertures (4)
386-393 F8.2 ct Nct-h ? Net hard (2-8 keV) counts in merged
apertures (4)
395-402 F8.2 ct b_Nct-t ? 1σ lower bound on Nct-t (4)(9)
404-411 F8.2 ct B_Nct-t ? 1σ upper bound on Nct-t (4)(9)
413-420 F8.2 ct b_Nct-s ? 1σ lower bound on Nct-s (4)(9)
422-429 F8.2 ct B_Nct-s ? 1σ upper bound on Nct-s (4)(9)
431-438 F8.2 ct b_Nct-h ? 1σ lower bound on Nct-h (4)(9)
440-447 F8.2 ct B_Nct-h ? 1σ upper bound on Nct-h (4)(9)
449-453 F5.3 keV E-t ? Median 0.5-8keV energy, observed
spectrum (4)(10)
455-461 F7.3 [ph/cm2/s] XFlx-t ? Log of incident photon flux in total
0.5-8 keV band (4)(11)
463-469 F7.3 [ph/cm2/s] XFlx-s ? Log of incident photon flux in soft
0.5-2 keV band (4)(11)
471-477 F7.3 [ph/cm2/s] XFlx-h ? Log of incident photon flux in hard
2-8 keV band (4)(11)
479-490 E12.6 10-7W LX-h ? X-ray luminosity in erg/s, 2-8 keV (12)
492-503 E12.6 10-7W LXc-h ? Absorption-corrected X-ray luminosity,
in erg/s; 2-8 keV (12)
505-516 E12.6 10-7W e_LXc-h ? LXhc 1σ statistical uncertainty (12)
518-529 E12.6 10-7W s_LXc-h ? LXhc 1σ systematic uncertainty (12)
531-542 E12.6 10-7W LX-t ? X-ray luminosity in erg/s, 0.5-8 keV (12)
544-555 E12.6 10-7W LXc-t ? Absorption-corrected X-ray luminosity,
in erg/s; 0.5-8 kev (12)
557-568 E12.6 10-7W e_LXc-t ? LXtc 1σ statistical uncertainty (12)
570-581 E12.6 10-7W s_LXc-t ? LXtc 1σ systematic uncertainty (12)
583-587 F5.2 cm-2 logNH ? Gas column density (12)
589-592 F4.2 cm-2 e_logNH ? logNH 1σ statistical error (12)
594-597 F4.2 cm-2 s_logNH ? logNH 1σ systematic uncertainty (12)
599-602 F4.2 --- pr.N [0/1]? Counterpart probability, X-ray/NIR (G5)
604-607 F4.2 --- pr.M [0/1]? counterpart probability, X-ray/MIR (G5)
609-614 F6.3 mag Jmag [4.7/25.2]? J-band magnitude
616-622 F7.3 mag e_Jmag [-25.1/3.3]? Jmag 1σ uncertainty
624-629 F6.3 mag Hmag [4.5/29.9]? H-band magnitude
631-637 F7.3 mag e_Hmag [-22.2/6.6]? Hmag 1σ uncertainty
639-644 F6.3 mag Kmag [4.3/21.5]? K-band magnitude
646-650 F5.3 mag e_Kmag ? Kmag 1-σ uncertainty
652-657 F6.3 mag [3.6] ? Spitzer/IRAC 3.6um band magnitude
659-663 F5.3 mag e_[3.6] ? [3.6] 1-σ uncertainty
665-670 F6.3 mag [4.5] ? Spitzer/IRAC 4.5um band magnitude
672-676 F5.3 mag e_[4.5] ? [4.5] 1-σ uncertainty
678-683 F6.3 mag [5.8] [2/17.5]? Spitzer/IRAC 5.8um band magnitude
685-689 F5.3 mag e_[5.8] [0/10]? [5.8] 1-σ uncertainty
691-696 F6.3 mag [8.0] [1.5/17]? Spitzer/IRAC 8.0um band magnitude
698-703 F6.3 mag e_[8.0] [0/15]? [8.0] 1-σ uncertainty
705-707 A3 --- f_Jmag UKIRT photometry flag on Jmag (G6)
709-711 A3 --- f_Hmag UKIRT photometry flag on Hmag (G6)
713-715 A3 --- f_Kmag UKIRT photometry flag on Kmag (G6)
717-719 A3 --- 2M 2MASS photometry flag
721-723 A3 --- q_2M 2MASS quality photometry flag
725-728 I4 --- n_Jmag GLIMPSE photometry flag on Jmag
730-733 I4 --- n_Hmag GLIMPSE photometry flag on Hmag
735-738 I4 --- n_Kmag GLIMPSE photometry flag on Kmag
740-744 I5 --- f_[3.6] GLIMPSE photometry flag on [3.6]
746-750 I5 --- f_[4.5] GLIMPSE photometry flag on [4.5]
752-757 I6 --- f_[5.8] GLIMPSE photometry flag on [5.8]
759-764 I6 --- f_[8.0] GLIMPSE photometry flag on [8.0]
766-768 I3 --- LS [-2/4]?=-99 Local Spitzer photometry flag (G7)
770-788 A19 --- r_Jmag Origin of Jmag photometry
790-808 A19 --- r_Hmag Origin of Hmag photometry
810-828 A19 --- r_Kmag Origin of Kmag photometry
830-848 A19 --- r_[3.6] Origin of [3.6] photometry
850-868 A19 --- r_[4.5] Origin of [4.5] photometry
870-888 A19 --- r_[5.8] Origin of [5.8] photometry
890-908 A19 --- r_[8.0] Origin of [8.0] photometry
910-912 I3 --- Cl [-2/2]?=-99 Classification (G8)
914-919 F6.3 mag Av [0/81]? Visual extinction AV
921-923 I3 --- St [-1/2]?=-99 YSO stage (G9)
925-928 F4.2 --- H1pr [0/1]? H1 class prior probability
(position-dependent)
930-933 F4.2 --- H2pr [0/1]? H2 class prior probability
(position-dependent)
935-938 F4.2 --- H3pr [0/1]? H3 class prior probability
(position-dependent)
940-943 F4.2 --- H4pr [0/1]? H4 class prior probability
(position-dependent)
945-948 F4.2 --- H1ps [0/1]? H1 class posterior probability
950-953 F4.2 --- H2ps [0/1]? H2 class posterior probability
955-958 F4.2 --- H3ps [0/1]? H3 class posterior probability
960-963 F4.2 --- H4ps [0/1]? H4 class posterior probability
965-967 I3 --- H2f [1/7]?=-99 H2 dominant classification
term (G10)
969-971 I3 --- Xcl [1/2]?=-99 X-ray classification (G11)
--------------------------------------------------------------------------------
Note (1): The MYStIX source name (MPCM) is the sexagesimal representation
of the MYStIX source position. In rare cases two MPCM rows will share
the same source position, because two X-ray sources have been assigned
the same NIR counterpart by our counterpart identification algorithm.
In such cases we append "a" or "b" to the source names to make them
unique. See section 2.
Note (2): When a source has been associated with a known massive star
(column "Olab") all XPHOT quantities (see Note (12)) are unreliable.
Note (3): References for SpT (number 0-10 are cited in Gagne et al., 2011,
Cat. J/ApJS/194/5) - see refs.dat file.
Note (4): These X-ray column labels were previously published by Broos et
al. (2011, Cat. J/ApJS/194/4; 2011, Cat. J/ApJS/194/2) and are
produced by the ACIS Extract (AE) software package (Broos et al.
2010ApJ...714.1582B 2010ApJ...714.1582B, 2012ascl.soft03001B). The AE software and User's
Guide are available at
http://www.astro.psu.edu/xray/acis/acis_analysis.html
Note (5): In statistical hypothesis testing, the p-value is the probability
of obtaining a test statistic at least as extreme as the one that was
actually observed when the null hypothesis is true.
Note (6): Smallest p-value for the one-sample Kolmogorov-Smirnov statistic
under the no-variability null hypothesis within a single-observation
or over merged observations. See Broos et al. (2010ApJ...714.1582B 2010ApJ...714.1582B,
Section 7.6) for a description of the variability metrics and caveats
regarding possible spurious indications of variability using the
ProbKS_merge metric.
Note (7): Due to dithering over inactive portions of the focal plane, a
Chandra source is often not observed during some fraction of the
nominal exposure time (See http://cxc.harvard.edu/ciao/why/dither.html).
The reported quantity is FRACEXPO produced by the CIAO tool mkarf.
Note (8): Some background events arising from an effect known as
"afterglow" (http://cxc.harvard.edu/ciao/why/afterglow.html) may
contaminate source extractions, despite careful procedures to identify
and remove them during data preparation (Broos et al.
2010ApJ...714.1582B 2010ApJ...714.1582B, Section 3). After extraction, we attempt to
identify afterglow events using the tool aeafterglowreport, and
report the fraction of extracted events attributed to afterglow; see
the ACIS Extract manual
(http://www.astro.psu.edu/xray/acis/acis_analysis.html).
Note (9): Confidence intervals (68%) for NetCounts quantities are estimated
by the CIAO tool aprates:
http://asc.harvard.edu/ciao/ahelp/aprates.html
Note (10): MedianEnergy ("MedEt") is the ACIS Extract quantity
"ENERGPCT50OBSERVED", the median energy of extracted events,
corrected for background (Broos et al. 2010ApJ...714.1582B 2010ApJ...714.1582B, #7.3).
Note (11): PhotonFlux
("PFlx")=(NetCounts/MeanEffectiveArea/ExposureTimeNominal) (Broos et
al. 2010ApJ...714.1582B 2010ApJ...714.1582B, Section 7.4).
Note (12): X-ray Spectral Model (XPHOT) from Getman et al. 2010, Cat.
J/ApJ/708/1760.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table7.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 16 A16 --- Reg MYStIX Galactic massive star-forming region
(MSFR) name
18- 35 A18 --- MPCM IAU source name (HHMMSS.ss+DDMMSS.s; J2000)
37- 46 F10.6 deg RAdeg Right ascension (J2000)
48- 57 F10.6 deg DEdeg Declination (J2000)
59- 63 F5.3 arcsec ePos [0/2.5] 1σ error around (RAdeg,DEdeg)
65- 71 A7 --- rPos Origin of position (G1)
73- 90 A18 --- CXO X-ray source name in IAU format
(HHMMSS.ss+DDMMSS.s; J2000)
92-102 A11 --- Xlab X-ray source name used within the MYStIX
project (G2)
104-121 A18 --- NName Name in NIR catalog (G3)
(HHMMSS.ss+DDMMSS.s; J2000)
123-138 A16 --- Nlab Label in NIR catalog
140-157 A18 --- MName Name in MIR catalog
(HHMMSS.ss+DDMMSS.s; J2000) (G4)
159-187 A29 --- Mlab Label in MIR catalog
189-192 F4.2 --- pr.N [0/1]? Counterpart probability, X-ray/NIR (G5)
194-197 F4.2 --- pr.M [0/1]? Counterpart probability, X-ray/MIR (G5)
199-204 F6.3 mag Jmag [4.7/25.7]? J-band magnitude
206-212 F7.3 mag e_Jmag [-25.1/3.6]? Jmag 1σ uncertainty
214-219 F6.3 mag Hmag [4.7/23.9]? H-band magnitude
221-227 F7.3 mag e_Hmag [-22.2/2.9]? Hmag 1σ uncertainty
229-234 F6.3 mag Kmag [4.4/19.5]? K-band magnitude
236-240 F5.3 mag e_Kmag ? Kmag 1σ uncertainty
242-247 F6.3 mag [3.6] ? Spitzer/IRAC 3.6um band magnitude
249-253 F5.3 mag e_[3.6] ? [3.6] 1-σ uncertainty
255-260 F6.3 mag [4.5] ? Spitzer/IRAC 4.5um band magnitude
262-266 F5.3 mag e_[4.5] ? [4.5] 1-σ uncertainty
268-273 F6.3 mag [5.8] [2.3/17.7]? Spitzer/IRAC 5.8um band magnitude
275-279 F5.3 mag e_[5.8] [0/9.8]? [5.8] 1-σ uncertainty
281-286 F6.3 mag [8.0] [1.5/17]? Spitzer/IRAC 8.0um band magnitude
288-295 F8.3 mag e_[8.0] [0/15.1]? [8.0] 1-σ uncertainty
297-299 A3 --- f_Jmag UKIRT photometry flag on Jmag (G6)
301-303 A3 --- f_Hmag UKIRT photometry flag on Hmag (G6)
305-307 A3 --- f_Kmag UKIRT photometry flag on Kmag (G6)
309-311 A3 --- 2M 2MASS photometry flag
313-315 A3 --- q_2M 2MASS photometry quality flag
317 I1 --- n_Jmag [0] GLIMPSE photometry flag on Jmag
319 I1 --- n_Hmag [0] GLIMPSE photometry flag on Hmag
321 I1 --- n_Kmag [0] GLIMPSE photometry flag on Kmag
323-327 I5 --- f_[3.6] GLIMPSE photometry flag on [3.6]
329-334 I6 --- f_[4.5] GLIMPSE photometry flag on [4.5]
336-341 I6 --- f_[5.8] GLIMPSE photometry flag on [5.8]
343-348 I6 --- f_[8.0] GLIMPSE photometry flag on [8.0]
350-352 I3 --- LS [-2/4]?=-99 Local Spitzer photometry flag (G7)
354-360 A7 --- r_Jmag Origin of Jmag photometry
362-368 A7 --- r_Hmag Origin of Hmag photometry
370-376 A7 --- r_Kmag Origin of Kmag photometry
378-390 A13 --- r_[3.6] Origin of [3.6] photometry
392-404 A13 --- r_[4.5] Origin of [4.5] photometry
406-418 A13 --- r_[5.8] Origin of [5.8] photometry
420-432 A13 --- r_[8.0] Origin of [8.0] photometry
434-436 I3 --- Cl [-2/2]?=-99 Classification (G8)
438-443 F6.3 mag Av [0/61]? Visual extinction AV
445-447 I3 --- St [-1/2]?=-99 YSO stage (G9)
449-452 F4.2 --- H1pr [0/1] H1 class prior probability
(position-dependent)
454-457 F4.2 --- H2pr [0/1] H2 class prior probability
(position-dependent)
459-462 F4.2 --- H3pr [0/1] H3 class prior probability
(position-dependent)
464-467 F4.2 --- H4pr [0/1] H4 class prior probability
(position-dependent)
469-472 F4.2 --- H1ps [0/1]? H1 class posterior probability
474-477 F4.2 --- H2ps [0/1]? H2 class posterior probability
479-482 F4.2 --- H3ps [0/1]? H3 class posterior probability
484-487 F4.2 --- H4ps [0/1]? H4 class posterior probability
489 I1 --- H2f [1/7] H2 dominant classification term (G10)
491 I1 --- Xcl [0/4]? X-ray classification (G11)
--------------------------------------------------------------------------------
Byte-by-byte Description of file: refs.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 A19 --- Ref Reference code
21- 39 A19 --- BibCode Bibcode
41- 62 A22 --- Aut Author's name(s)
64- 97 A34 --- Comm Comment
--------------------------------------------------------------------------------
Global notes:
Note (G1): The MYStIX source position is the most accurate position among
the multiwavelength detections that we judged to be the same object:
a Chandra X-ray position, UKIRT or 2MASS NIR position, or a Spitzer
MIR position:
Megeath2012 = Megeath et al., 2012AJ....144..192M 2012AJ....144..192M (Spitzer survey of
Orion A and B molecular clouds).
OBcat = Massive stars (B3 or earlier) were drawn from the literature
collections of Skiff (2009, Cat. B/mk) and SIMBAD, and from a list
given in section 2. Note that these spectroscopically identified OB
stars typically do not have IR excesses and some, but not all, have
X-ray detections.
Chandra = X-ray position
Spitzer = Mid-IR position from Spitzer
UKIDSS = near-IR position from UKIDSS survey (see II/316, II/319)
TWOMASS = near-IR position from 2MASS (Cat. II/246)
Note (G2): X-ray source labels identify a Chandra pointing; they do not
convey membership in astrophysical clusters. L.K. Townsley & P.S.
Broos (2013, in preparation) and Kuhn et al. (2013, J/ApJS/209/27)
identify a few very bright X-ray sources in each region that suffer
from a type of instrumental non-linearity known as photon pile-up
(http://cxc.harvard.edu/ciao/why/pileup_intro.html); X-ray properties
reported for those sources are biased and should be used with caution.
Note (G3): NIR catalogs were constructed by combining deep UKIRT catalogs
(King et al. 2013ApJS..209...28K 2013ApJS..209...28K) where available, with bright stars
from the 2MASS catalog (Skrutskie et al. 2006, Cat. VII/233).
Note (G4): MIR catalogs were obtained from local reductions of Spitzer
observations (Kuhn et al. 2013, J/ApJS/209/29), from the Spitzer
Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE;
Benjamin et al. 2003PASP..115..953B 2003PASP..115..953B, see Cat. II/293), and from the
Vela-Carina Survey (Spitzer Proposal ID 40791, PI S. Majewski).
Feigelson et al. (2013ApJS..209...26F 2013ApJS..209...26F, Table 2) report which IR
catalogs were available for each MYStIX MSFR.
Note (G5): Counterpart probability from Naylor et al. 2013, Cat. J/ApJS/209/30.
Note (G6): UKIRT photometry flag (King et al. 2013, Cat. J/ApJS/209/28)
Note (G7): "Local Spitzer" photometry flag (Kuhn et al. 2013,
Cat. J/ApJS/209/29) as follows:
4 = 4-pixel aperture used;
3 = 3-pixel aperture used;
2 = 2-pixel aperture used and contaminating flux is <10% of source flux;
-1 = 2-pixel aperture used and contaminating flux is >10% of source flux.
Note (G8): SED Properties (Povich et al. 2013, Cat. J/ApJS/209/31) with SED
classification as follows:
0 = likely YSO,
1 = starburst galaxy,
2 = AGN,
3 = PAH knot
Note (G9): Evolutionary Stage classification as follows:
1 = stage 0/1,
2 = Stage II/III
-1 = ambiguous.
Note (G10): H2dominantfactor ("H2f") reports the classifier term that exerts
the most influence on the H2 posterior probability as follows:
1 = prior,
2 = MedianEnergy,
3 = J magnitude,
4 = X-ray variability,
5 = spectral type,
6 = 4.5um magnitude,
7 = infrared SED model.
Note (G11): Classification in X-ray as follows:
0 = unclassified
1 = H1: source is a foreground Galactic field star
2 = H2: source is a young star in the MSFR (Galactic massive star-forming
region)
3 = H3: source is a background Galactic field star
4 = H4: source is an extragalactic object
--------------------------------------------------------------------------------
History:
From electronic version of the journal
References:
Feigelson et al. Overview. 2013ApJS..209...26F 2013ApJS..209...26F
Kuhn et al. X-ray sources. 2013ApJS..209...27K 2013ApJS..209...27K Cat. J/ApJS/209/27
King et al. Crowded fields. 2013ApJS..209...28K 2013ApJS..209...28K Cat. J/ApJS/209/28
Kuhn et al. MIR. 2013ApJS..209...29K 2013ApJS..209...29K Cat. J/ApJS/209/29
Naylor et al. Bayesian matching. 2013ApJS..209...30N 2013ApJS..209...30N Cat. J/ApJS/209/30
Povich et al. IR excess cat. 2013ApJS..209...31P 2013ApJS..209...31P Cat. J/ApJS/209/31
Broos et al. Young stars. 2013ApJS..209...32B 2013ApJS..209...32B (this paper)
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 09-Jan-2014