J/AJ/154/87 Stellar population of the young star cluster NGC 6231 (Kuhn+, 2017)
The structure of the young star cluster NGC 6231.
I. Stellar population.
Kuhn M.A., Medina N., Getman K.V., Feigelson E.D., Gromadzki M.,
Borissova J., Kurtev R.
<Astron. J., 154, 87 (2017)>
=2017AJ....154...87K 2017AJ....154...87K (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, open ; Stellar distribution ; Stars, pre-main sequence ;
X-ray sources ; Stars, variable ; Stars, OB ; Spectral types ;
Photometry, UBVRIJKLMNH ; Populations, stellar
Keywords: open clusters and associations: individual (NGC 6231) -
stars: formation - stars: massive - stars: pre-main sequence -
stars: variables: T Tauri, Herbig Ae/Be - X-rays: stars
Abstract:
NGC 6231 is a young cluster (age ∼2-7 Myr) dominating the Sco OB1
association (distance ∼1.59 kpc) with ∼100 O and B stars and a large
pre-main-sequence stellar population. We combine a reanalysis of
archival Chandra X-ray data with multiepoch near-infrared (NIR)
photometry from the VISTA Variables in the Via Lactea (VVV) survey and
published optical catalogs to obtain a catalog of 2148 probable
cluster members. This catalog is 70% larger than previous censuses of
probable cluster members in NGC 6231. It includes many low-mass stars
detected in the NIR but not in the optical and some B stars without
previously noted X-ray counterparts. In addition, we identify 295 NIR
variables, about half of which are expected to be pre-main-sequence
stars. With the more complete sample, we estimate a total population
in the Chandra field of 5700-7500 cluster members down to 0.08 M☉
(assuming a universal initial mass function) with a completeness limit
at 0.5 M☉. A decrease in stellar X-ray luminosities is noted
relative to other younger clusters. However, within the cluster, there
is little variation in the distribution of X-ray luminosities for ages
less than 5 Myr. The X-ray spectral hardness for B stars may be useful
for distinguishing between early-B stars with X-rays generated in
stellar winds and B-star systems with X-rays from a pre-main-sequence
companion (>35% of B stars). A small fraction of catalog members have
unusually high X-ray median energies or reddened NIR colors, which
might be explained by absorption from thick or edge-on disks or being
background field stars.
Description:
This work makes use of some basic cluster properties available from
the literature. Summaries of older studies are provided by Sana et al.
(2006, J/A+A/454/1047) and Reipurth (2008hsf2.book.....R 2008hsf2.book.....R). Expanded
catalogs of cluster members have been provided by Sung et al. (2013,
J/AJ/145/37) and Damiani et al. 2016, J/A+A/596/A82 (DMS2016).
Chandra X-ray observations were made using the imaging array on the
Advanced CCD Imaging Spectrometer (ACIS-I; Garmire et al.
2003SPIE.4851...28G 2003SPIE.4851...28G). This instrument is an array of four CCD detectors
that subtends 17'x17'. The target was observed in 2005 July (Sequence
200307; PI: S. Murray) in two observations (ObsID 5372 and 6291), and
the data were retrieved from the Chandra Data Archive.
The NIR ZYJHKs data were obtained from the VVV survey (Minniti et al.
2010NewA...15..433M 2010NewA...15..433M; Saito et al. 2012, Cat. II/337). VVV is a multiepoch
NIR survey that covers both the Galactic bulge and an adjacent Galactic
disk region and was carried out using the 4.1 m VISTA telescope on
Cerro Paranal. The VVV data were taken with the VISTA Infrared CAMera
(VIRCAM; Dalton et al. 2006SPIE.6269E..0XD), a 4x4 array of Raytheon VIRGO
2048x2048 20 µm pixel detectors with a pixel scale of 0.34".
In addition to the VVV photometry, public optical or infrared catalogs
are available from surveys and publications. We have included VPHAS+
photometry (Drew et al. 2014, J/MNRAS/440/2036), UBVRI (Johnson-Cousins
system) and Hα photometry from Sung et al. (2013, J/AJ/145/37), and
Spitzer/IRAC photometry from the GLIMPSE survey (Benjamin et al. 2003,
Cat. II/293).
Objects:
--------------------------------------------------------
RA (ICRS) DE Designation(s)
--------------------------------------------------------
16 54 08.51 -41 49 36.0 NGC 6231 = Cl Collinder 315
--------------------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 608 2411 *X-Ray Sources and Properties
table3.dat 660 2148 NGC 6231 CXOVVV Probable Cluster Member Catalog
table4.dat 76 295 VVV Ks-band Variables
table5.dat 128 99 Chandra X-ray properties of OB stars
--------------------------------------------------------------------------------
Note on table1.dat: X-ray source properties from ACIS Extract (Broos et al.
2010ApJ...714.1582B 2010ApJ...714.1582B) and XPHOT (Getman et al. 2010, J/ApJ/708/1760). Column
definitions are identical to those in Kuhn et al. (2013, J/ApJS/209/27). Rows
are sorted by RAdeg.
Source significance quantities (noSrc-t, noSrc-s, noSrc-h, noSrc-m) are
computed using a subset of each source's extractions chosen to maximize
significance (Broos et al. 2010ApJ...714.1582B 2010ApJ...714.1582B, Section 6.2). Source position
quantities (RAdeg, DEdeg, ePos) are computed using a subset of each source's
extractions chosen to minimize the position uncertainty (Broos et al.
2010ApJ...714.1582B 2010ApJ...714.1582B, Sections 6.2 and 7.1). All other quantities are computed
using a subset of each source's extractions chosen to balance the conflicting
goals of minimizing photometric uncertainty and avoiding photometric bias
(Broos et al. 2010ApJ...714.1582B 2010ApJ...714.1582B, Sections 6.2 and 7).
--------------------------------------------------------------------------------
See also:
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
II/293 : GLIMPSE Source Catalog (I + II + 3D) (IPAC 2008)
II/337 : VISTA Variables in the Via Lactea Survey DR1 (Saito+, 2012)
J/A+A/325/167 : Geneva photometry in NGC 6231 (Raboud+ 1997)
J/AJ/115/734 : NGC 6231 UBVRI and Hα photometry (Sung+ 1998)
J/A+AS/137/233 : UBVI imaging photometry of NGC 6231 (Baume+, 1999)
J/A+A/454/1047 : XMM view of NGC 6231 open cluster (Sana+, 2006)
J/MNRAS/372/661 : XMM view of NGC 6231: OB stars (Sana+, 2006)
J/MNRAS/386/447 : RV catalogue of O-type stars in NGC 6231 (Sana+, 2008)
J/ApJ/708/1760 : Flux estimations of faint X-ray sources (Getman+, 2010)
J/AJ/145/37 : UBVI and Hα CCD photometry of NGC 6231 (Sung+, 2013)
J/ApJS/209/27 : MYStIX: the Chandra X-ray sources (Kuhn+, 2013)
J/MNRAS/440/2036 : VPHAS+ survey synthetic colours (Drew+, 2014)
J/A+A/596/A82 : X-ray study of the young cluster NGC6231 (Damiani+, 2016)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 18 A18 --- CXOU X-ray source name;
CXOU J(HHMMSS.ss+DDMMSS.s) (Name)
20- 26 A7 --- Label Source name generated by ACIS Extract
(Label) (1)
28- 37 F10.6 deg RAdeg Right Ascension in decimal degrees (J2000)
(RAdeg)
39- 48 F10.6 deg DEdeg Declination in decimal degrees (J2000)
(DEdeg)
50- 57 F8.6 arcsec ePos 1σ error circle around (RAdeg, DEdeg)
(PosErr)
59- 75 A17 --- PosType Algorithm used to estimate position
(Broos et al. 2010ApJ...714.1582B 2010ApJ...714.1582B,
Section 7.1) (PosType)
77- 88 E12.7 --- no-m Smallest of no-t, no-s and no-h
(ProbNoSrc_min) (2)
90-101 E12.7 --- no-t p-value for no-source hypothesis in the
total (0.5-8 keV) energy band
(ProbNoSrc_t) (2)
103-114 E12.7 --- no-s ? p-value for no-source hypothesis in the
soft (0.5-2 keV) energy band (ProbNoSrc_s)
(2)
116-127 E12.7 --- no-h ? p-value for no-source hypothesis in the
hard (2-8 keV) energy band (ProbNoSrc_h)
(2)
129-140 E12.7 --- KS-s ? Smallest p-value for the one-sample
Kolmogorov-Smirnov statistic under the
no-variability null hypothesis within a
single observation (ProbKS_single) (3)
142-153 E12.7 --- KS-m ? Smallest p-value for the one-sample
Kolmogorov-Smirnov statistic under the
no-variability null hypothesis over merged
observations (ProbKS_merge) (3)
155-162 F8.1 s ExpNom [44384.3/120591] Total exposure time in
merged observations (ExposureTimeNominal)
164-171 F8.6 --- ExpFrac Fraction of ExpNom that source was observed
(ExposureFraction) (4)
173 I1 --- Nobs [1/2] Total number of observations
extracted (NumObservations)
175 I1 --- Nph [1/2] Number of observations merged to
estimate photometry properties (NumMerged)
177-184 F8.6 --- Fdis [0/0.35725] Fraction of exposure discarded
in merge (MergeBias)
186-194 F9.6 arcmin theta-m Smallest off-axis angle for merged
observations (Theta_Lo)
196-204 F9.6 arcmin theta Average off-axis angle θ for merged
observations (Theta)
206-214 F9.6 arcmin theta-M Largest off-axis angle for merged
observations (Theta_Hi)
216-223 F8.6 --- PSFf Average PSF fraction (at 1.5 keV) for
merged observations (PsfFraction)
225-234 F10.5 --- Area [1.16494/2098.42] Average aperture area for
merged observations (in units of
(0.492arcsec)2) (SrcArea)
236-242 F7.5 --- aglow [0/0.5]? Suspected afterglow fraction
(AfterglowFraction) (5)
244-247 I4 ct Oct-t [3/5448] Observed 0.5-8 keV counts in
merged apertures (SrcCounts_t)
249-252 I4 ct Oct-s [0/4787] Observed 0.5-2 keV counts in
merged apertures (SrcCounts_s)
254-256 I3 ct Oct-h [0/661] Observed 2-8 keV counts in merged
apertures (SrcCounts_h)
258-267 F10.6 --- bgScl Scaling of the background extraction
(Broos et al. 2010ApJ...714.1582B 2010ApJ...714.1582B,
Section 5.4) (BkgScaling)
269-272 I4 ct bgct-t [0/1508] Observed 0.5-8 keV counts in
merged background regions (BkgCounts_t)
274-277 I4 ct bgct-s [0/1442] Observed 0.5-2 keV counts in
merged background regions (BkgCounts_s)
279-281 I3 ct bgct-h [0/264] Observed 2-8 keV counts in merged
background regions (BkgCounts_h)
283-292 F10.5 ct Nct-t [1.64829/5447] Net 0.5-8 keV counts in
merged apertures (NetCounts_t)
294-303 F10.5 ct Nct-s [-4.91924/4786.09277] Net 0.5-2 keV counts
in merged apertures (NetCounts_s)
305-313 F9.5 ct Nct-h [-6.25827/660.906] Net 2-8 keV counts in
merged apertures (NetCounts_h)
315-324 F10.5 ct b_Nct-t [0/5373.19] 1σ lower bound on Nct-t
(NetCountsLot) (6)
326-335 F10.5 ct B_Nct-t [3.62988/5521.55] 1σ upper bound on
Nct-t (NetCountsHit) (6)
337-346 F10.5 ct b_Nct-s [0/4716.9]? 1σ lower bound on Nct-s
(NetCountsLos) (6)
348-357 F10.5 ct B_Nct-s [1.14885/4855.97021] 1σ upper bound
on Nct-s (NetCountsHis) (6)
359-367 F9.5 ct b_Nct-h [0/635.196]? 1σ lower bound on Nct-h
(NetCountsLoh) (6)
369-377 F9.5 ct B_Nct-h [1.13821/686.873] 1σ upper bound on
Nct-h (NetCountsHih) (6)
379-386 F8.4 cm2.ct/ph Area-t [29.1045/241.377] Mean 0.5-8 keV ARF value
(MeanEffectiveArea_t) (7)
388-395 F8.4 cm2.ct/ph Area-s [40.9269/335.0584] Mean 0.5-2 keV ARF value
(MeanEffectiveArea_s) (7)
397-404 F8.4 cm2.ct/ph Area-h [26.1417/217.904] Mean 2-8 keV ARF value
(MeanEffectiveArea_h)(7)
406-411 F6.4 keV E-t [0.6351/6.4897] Median 0.5-8 keV energy,
observed spectrum (MedianEnergy_t) (8)
413-418 F6.4 keV E-s [0.5037/1.9929]? Median 0.5-2 keV energy,
observed spectrum (MedianEnergy_s) (8)
420-425 F6.4 keV E-h [2.0075/7.9643]? Median 2-8 keV energy,
observed spectrum (MedianEnergy_h) (8)
427-434 F8.5 [ph/cm2/s] logF-t [-7.21629/-3.36091] Log incident 0.5-8 keV
photon flux (PhotonFlux_t) (9)
436-443 F8.5 [ph/cm2/s] logF-s [-9.45495/-3.56744]? Log incident 0.5-2 keV
photon flux (PhotonFlux_s) (9)
445-453 F9.5 [ph/cm2/s] logF-h [-11.136/-4.22939]? Log incident 2-8 keV
photon flux (PhotonFlux_h) (9)
455-466 E12.7 mW/m2 Flux-h ? 2-8 keV X-ray flux (in erg/cm2/s) (FH)
(10)
468-479 E12.7 mW/m2 Flxc-h ? Absorption-corrected 2-8 keV X-ray flux
(in erg/cm2/s) (FHC) (10)
481-492 E12.7 mW/m2 e_Flxc-h ? 1σ statistical uncertainty on
Flxc-h (in erg/cm2/s) (SFHCSTAT) (10)
494-505 E12.7 mW/m2 s_Flxc-h ? 1σ systematic uncertainty on Flxc-h
(in erg/cm2/s) (SFHCSYST) (10)
507-518 E12.7 mW/m2 Flux-t ? 0.5-8 keV X-ray flux (in erg/cm2/s)
(FT) (10)
520-531 E12.7 mW/m2 Flxc-t ? Absorption-corrected 0.5-8 keV X-ray flux
(in erg/cm2/s) (FTC) (10)
533-544 E12.7 mW/m2 e_Flxc-t ? 1σ statistical uncertainty on
Flxc-t (in erg/cm2/s) (SFTCSTAT) (10)
546-557 E12.7 mW/m2 s_Flxc-t ? 1σ systematic uncertainty on Flxc-t
(in erg/cm2/s) (SFTCSYST) (10)
559-564 F6.3 [cm-2] logNH [20/24]? Gas column density (LOG_NH) (10)
566-571 F6.4 [cm-2] e_logNH [0/1.0265]? 1σ statistical
uncertainty on logNH (SLOGNHSTAT) (10)
573-578 F6.4 [cm-2] s_logNH [0/1.15]? 1σ systematic uncertainty
on logNH (SLOGNHSYST) (10)
580-586 F7.4 [10-7W] logLX-t [29.0926/32.4171]? Log X-ray (0.5-8 keV)
luminosity (in erg/s) (LOG_LTC) (10)
588-594 F7.4 [10-7W] logLX-s [28.9726/31.9344]? Log X-ray (0.5-2 keV)
luminosity (in erg/s) (LOG_LHC) (10)
596-601 F6.4 [10-7W] e_logLX-t [0.0198/2.1081]? 1σ statistical
uncertainty on logLX-t (in erg/s)
(ERRLOGLTC) (10)
603-608 F6.4 [10-7W] e_logLX-s [0.0568/1.9381]? 1σ statistical
uncertainty on logLX-s (in erg/s)
(ERRLOGLHC) (10)
--------------------------------------------------------------------------------
Note (1): Source labels identify a Chandra pointing; they do not convey
membership in astrophysical clusters.
Note (2): Source significance quantities (noSrc-t, noSrc-s, noSrc-h, noSrc-m)
are computed using a subset of each source's extractions chosen to maximize
significance (Broos et al. 2010ApJ...714.1582B 2010ApJ...714.1582B, Section 6.2).
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.
(See Broos et al. 2010ApJ...714.1582B 2010ApJ...714.1582B, Section 4.3).
Note (3): 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 (4): 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 (5): 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 (6): Confidence intervals (68%) for NetCounts quantities are estimated by
the CIAO tool aprates (http://asc.harvard.edu/ciao/ahelp/aprates.html).
Note (7): The ancillary response file (ARF) in ACIS data analysis represents
both the effective area of the observatory and the fraction of the observation
for which data were actually collected for the source (ExposureFraction).
Note (8): MedianEnergy is the ME of extracted events, corrected for background
(Broos et al. 2010ApJ...714.1582B 2010ApJ...714.1582B, Section 7.3).
Note (9): XFlx=(Nct/Area/ExpNom); Broos et al. 2010ApJ...714.1582B 2010ApJ...714.1582B, Section 7.4.
Note (10): XPHOT assumes X-ray spectral shapes of young, low-mass stars, which
come from coronal X-ray emission. XPHOT quantities will therefore be
unreliable for high-mass stars, for which X-ray emission is associated with
the stellar wind (Getman et al. 2010, J/ApJ/708/1760).
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 A19 --- CXOVVV IAU source name;
CXOVVV (JHHMMSS.ss+DDMMSS.s) (Name)
21- 30 F10.6 deg RAdeg Right Ascension in decimal degrees
(J2000) (Catalog_RAdeg)
32- 41 F10.6 deg DEdeg Declination in decimal degrees (J2000)
(Catalog_DEdeg)
43- 60 A18 --- CXOU X-ray source name;
CXOU J(HHMMSS.ss+DDMMSS.s) (Xray_Name)
62- 67 F6.4 keV ME [0.6351/6.0809]? X-ray median energy in
the total 0.5-8.0 keV band (ME)
69- 76 F8.5 [10-7W] logLX-t [28.7075/32.4171]? Absorption-corrected
X-ray luminosity in the 0.5-8.0 keV band
(in erg/s) (LogLx)
78- 85 F8.5 [ph/cm2/s] logF-t [-7.21629/-3.36091]? Log incident photon
flux in the 0.5-8.0 keV band
(PhotonFlux)
87- 92 I6 --- HD [152200/326340]? OB star name in the HD
catalog (Cannon 1936AnHar.100....1C 1936AnHar.100....1C)
(HD)
94- 97 I4 --- CPD [7689/7762]? OB star name in the CPD
catalog (Gill & Kapteyn
1897AnCap...4....1G 1897AnCap...4....1G) (CPD-41d)
99-101 I3 --- Segg [0/769]? OB star name in the Seggewiss
(1968ZA.....68..142S 1968ZA.....68..142S) catalog (Segg)
103-105 I3 --- SBL98 [20/862]? OB star name in the Sung et al.
(1998, J/AJ/115/734) catalog (SBL98)
107-109 I3 --- BVF99 [1/166]? OB star name in the Baume et al.
(1999, J/A+AS/137/233) catalog (BVF99)
111-129 A19 --- SpType Spectral type tabulated by Sana et al.
(2006, J/MNRAS/372/661) (SpType)
131-141 A11 --- r_SpType Reference(s) for spectral type given by
Sana et al. (2006, J/MNRAS/372/661)
(r_SpType) (1)
143-146 I4 --- DMSM2016 [1/1778]? Source name in the DMS2016
catalog (Damiani et al. 2016,
J/A+A/596/A82) (DMSM2016_Name)
148 I1 --- Memb [1/6]? Membership classification in the
DMS2016 catalog (DMS2016_Group)
150-167 A18 --- VVVv Source name in the catalog of Ks
variables in VVV (HHMMSS.ss+DDMMSS.s)
(VVVv)
169-178 F10.6 deg RAVdeg ? Right ascension of VVV source in
decimal degrees (J2000) (VVV_RAdeg)
180-189 F10.6 deg DEVdeg ? Declination of VVV source in decimal
degrees (J2000) (VVV_DEdeg)
191-196 F6.3 mag KsmagV [7.96/18.119]? VVV Ks-band magnitude
(Ks_VVV)
198-202 F5.3 mag e_KsmagV [0.01/0.316]? 1σ uncertainty in
KsmagV (eKsVVV)
204-205 I2 --- f_KsmagV [-9/-1]? Cambridge Astronomical Survey
Unit (CASU) flag on KsmagV (flagKsVVV)
(2)
207-212 F6.3 mag HmagV [8.565/18.84]? VVV H-band magnitude
(H_VVV)
214-218 F5.3 mag e_HmagV [0.01/0.344]? 1σ uncertainty in
HmagV (eHVVV)
220-221 I2 --- f_HmagV [-9/-1]? CASU flag on HmagV (flagHVVV)
(2)
223-228 F6.3 mag JmagV [8.245/19.285]? VVV J-band magnitude
(J_VVV)
230-234 F5.3 mag e_JmagV [0.01/0.239]? 1σ uncertainty in
JmagV (eJVVV)
236-237 I2 --- f_JmagV [-9/-1]? CASU flag on JmagV (flagJVVV)
(2)
239-244 F6.3 mag YmagV [8.622/20.427]? VVV Y-band magnitude
(Y_VVV)
246-250 F5.3 mag e_YmagV [0.01/0.352]? 1σ uncertainty in
YmagV (eYVVV)
252-253 I2 --- f_YmagV [-9/-1]? CASU flag on YmagV (flagYVVV)
(2)
255-260 F6.3 mag ZmagV [9.011/20.702]? VVV Z-band magnitude
(Z_VVV)
262-266 F5.3 mag e_ZmagV [0.01/0.292]? 1σ uncertainty in
ZmagV (eZVVV)
268-269 I2 --- f_ZmagV [-9/-1]? CASU flag on ZmagV (flagZVVV)
(2)
271-286 A16 --- 2MASS Source name in the 2MASS catalog
(HHMMSSss+DDMMSSs) (2MASS_ID)
288-293 F6.3 mag Jmag2 [5.07/17.268]? 2MASS J-band magnitude
(J_2M)
295-299 F5.3 mag e_Jmag2 [0.019/0.91]? 1σ uncertainty in
Jmag2 (eJ2M)
301-306 F6.3 mag Hmag2 [4.926/16.154]? 2MASS H-band magnitude
(H_2M)
308-312 F5.3 mag e_Hmag2 [0.021/1.297]? 1σ uncertainty in
Hmag2 (eH2M)
314-319 F6.3 mag Ksmag2 [4.773/15.96]? 2MASS Ks-band magnitude
(Ks_2M)
321-325 F5.3 mag e_Ksmag2 [0.016/0.477]? 1σ uncertainty in
Ksmag2 (eKs2M)
327-329 A3 --- Qflg 2MASS JHK photometric quality flag (Qflg)
(3)
331-333 I3 --- Rflg [2/662]? Source of JHK default mag (Rflg)
(3)
335-337 I3 --- Bflg [1/330]? JHK components fit to source
(Bflg) (3)
339-341 A3 --- Cflg Artifact contamination, confusion
(Cflg) (3)
343 I1 --- Xflg [0]? Extended source contamination
(Xflg) (3)
345 I1 --- Aflg [0]? Association with asteroid or comet
(Aflg) (3)
347-351 F5.2 mag Jmag2V [5.07/19.11]? Merged 2MASS and VVV
J-band photometry in the 2MASS system
(J_synth)
353-357 F5.2 mag Hmag2V [4.93/17.84]? Merged 2MASS and VVV
H-band photometry in the 2MASS system
(H_synth)
359-363 F5.2 mag Ksmag2V [4.77/17.51]? Merged 2MASS and VVV
Ks-band photometry in the 2MASS system
(Ks_synth)
365-377 A13 --- VPHAS Source name in the VPHAS+ catalog
(Drew et al. 2014, J/MNRAS/440/2036)
(VPHAS_ID)
379-383 F5.2 mag umag [10.93/21.29]? VPHAS u-band magnitude
(umag)
385-388 F4.2 mag e_umag [0/0.3]? 1σ uncertainty in umag
(e_umag)
390-394 F5.2 mag gmag [13.06/22.7]? VPHAS g-band magnitude
(gmag)
396-399 F4.2 mag e_gmag [0/0.35]? 1σ uncertainty in gmag
(e_gmag)
401-405 F5.2 mag r2mag [12.78/21.87]? VPHAS r2-band magnitude
(r2mag)
407-410 F4.2 mag e_r2mag [0/0.22]? 1σ uncertainty in r2mag
(e_r2mag)
412-416 F5.2 mag Hamag [10.78/20.78]? VPHAS Hα-band
magnitude (Hamag)
418-421 F4.2 mag e_Hamag [0/0.26]? 1σ uncertainty in Hamag
(e_Hamag)
423-427 F5.2 mag rmag [12.3/21.6]? VPHAS r-band magnitude
(rmag)
429-432 F4.2 mag e_rmag [0/0.27]? 1σ uncertainty in rmag
(e_rmag)
434-438 F5.2 mag imag [11.77/20.99]? VPHAS i-band magnitude
(imag)
440-443 F4.2 mag e_imag [0/0.23]? 1σ uncertainty in imag
(e_imag)
445-449 I5 --- SSB2013 [-14/23016]? Source name in the
Sung et al. (2013, J/AJ/145/37) catalog
(SSB2013_ID)
451-456 F6.3 mag Vmag [6.088/21.666]? V-band magnitude in the
CIT system (Vmag)
458-462 F5.3 mag e_Vmag [0/0.234]? 1σ uncertainty in Vmag
(e_Vmag)
464-468 F5.3 mag V-I [0.275/4.116]? V-I color (V-I)
470-474 F5.3 mag e_V-I [0/0.239]? 1σ uncertainty in V-I
(e_V-I)
476-480 F5.3 mag B-V [0.135/2.182]? B-V color (B-V)
482-486 F5.3 mag e_B-V [0/0.236]? 1σ uncertainty in B-V
(e_B-V)
488-493 F6.3 mag U-B [-0.806/1.547]? U-B color (U-B)
495-499 F5.3 mag e_U-B [0.001/0.191]? 1σ uncertainty in
U-B (e_U-B)
501-506 F6.3 mag HamagSSB [-1.215/0.343]? SSB Hα magnitude
(Ha_SSB)
508-512 F5.3 mag e_HamagSSB [0.001/0.308]? 1σ uncertainty in
HamagSSB (eHaSSB)
514-530 A17 --- GLIMPSE Source name in the GLIMPSE catalog
(GLLL.llll+BB.bbbb) (Benjamin et al.
2003, Cat. II/293) (GLIMPSE_ID)
532-537 F6.3 mag 3.6mag [8.991/14.743]? Spitzer/IRAC 3.6µm
band magnitude (3_6mag)
539-543 F5.3 mag e_3.6mag [0.034/0.18]? 1σ uncertainty in
3.6mag (e36mag)
545-552 I8 --- q_3.6mag [0/110000]? GLIMPSE quality flag on
3.6mag (q36mag) (4)
554-559 F6.3 mag 4.5mag [9.095/14.241]? Spitzer/IRAC 4.5µm
band magnitude (4_5mag)
561-565 F5.3 mag e_4.5mag [0.045/0.306]? 1σ uncertainty in
4.5mag (e45mag)
567-574 A8 --- q_4.5mag GLIMPSE quality flag on 4.5mag (q45mag)
(4)
576-581 F6.3 mag 5.8mag [9.04/12.878]? Spitzer/IRAC 5.8µm
band magnitude (5_8mag)
583-587 F5.3 mag e_5.8mag [0.036/0.311]? 1σ uncertainty in
5.8mag (e58mag)
589-596 A8 --- q_5.8mag GLIMPSE quality flag on 5.8mag (q58mag)
(4)
598-603 F6.3 mag 8.0mag [9.012/12.545]? Spitzer/IRAC 8.0µm
band magnitude (8_0mag)
605-609 F5.3 mag e_8.0mag [0.028/0.334]? 1σ uncertainty in
8.0mag (e80mag)
611-618 A8 --- q_8.0mag GLIMPSE quality flag on 8.0mag (q80mag)
(4)
620-623 F4.2 mag Ak [0/2.06]? Estimated absorption in the
Ks-band (AK) (Ak)
625-628 F4.1 Myr Age [0.1/20]? Age estimated from the V versus
V-I diagram (age_vi)
630-634 F5.2 Msun logM(3.2) [-1.36/1.63]? Estimated mass for an age
of 3.2 Myr (logM32Myr)
636-640 F5.2 Msun logM(6.4) [-1.14/1.63]? Estimated mass for an age
of 6.4 Myr (logM64Myr)
642-646 F5.2 Lsun logL(3.2) [-1.13/5.75]? Estimated luminosity for
an age of 3.2 Myr (logL32Myr)
648-652 F5.2 Lsun logL(6.4) [-1.53/5.75]? Estimated luminosity for
an age of 6.4 Myr (logL64Myr)
654 I1 --- Ksexcess [0/1] Indicator of Ks-band excess
(Ks_excess)
656 I1 --- ClassI [0/1] Indicator of classification as
a Class I YSO (classI)
658 I1 --- ClassII [0/1] Indicator of classification as
a Class II YSO (classII)
660 I1 --- IRexcess [0/1] Indicator of infrared excess
(IR_excess)
--------------------------------------------------------------------------------
Note (1): References as described in Sana et al. (2006, J/MNRAS/372/661) are as
follows:
Bra67 = Braes 1967BANS....2....1B 1967BANS....2....1B;
GM01 = Garcima & Mermilliod 2001A&A...368..122G 2001A&A...368..122G;
GaS79 = Garrison & Schild 1979AJ.....84.1020G 1979AJ.....84.1020G;
LM80 = Levato & Malaroda 1980PASP...92..323L 1980PASP...92..323L;
LM83 = Levato & Morrell 1983ApL....23..183L 1983ApL....23..183L;
Lav72 = Laval 1972A&A....21..271L 1972A&A....21..271L;
PHYB90 = Perry et al. 1990A&AS...86..415P 1990A&AS...86..415P;
SAR05 = Sana et al. 2005A&A...441..213S 2005A&A...441..213S;
SGR06 = Sana, Rauw & Gosset 2007ApJ...659.1582S 2007ApJ...659.1582S;
SIMBAD = SIMBAD database, http://simbad.u-strasbg.fr/sim-fid.pl;
SNW71 = Schild et al. 1971AJ.....76..237S 1971AJ.....76..237S;
SRG01 = Sana et al. 2001A&A...370..121S 2001A&A...370..121S;
San05 = Sana 2005, PhD Thesis, Liege University, Belgium;
San06 = Sana et al. 2007MNRAS.377..945S 2007MNRAS.377..945S.
Note (2): Flags indicate the morphological classifications of sources, which are
generated based on curve-of-growth analysis (Irwin et al.
2004SPIE.5493..411I 2004SPIE.5493..411I). We make use of sources with flags as follows:
-1 = Stellar;
-2 = Borderline stellar;
-9 = Saturated in the analysis.
Note (3): Adopted from the 2MASS catalog (see Cat. II/246 for details).
Note (4): Adopted from the GLIMPSE Source Catalog (see Cat. II/293 for details).
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 18 A18 --- VVVv VVV variable designation (HHMMSS.ss+DDMMSS.s)
20- 37 A18 --- CXOU X-ray source designation;
CXOU J(HHMMSS.ss+DDMMSS.s)
39- 49 F11.7 deg RAdeg Right Ascension in decimal degrees (J2000)
51- 61 F11.7 deg DEdeg Declination in decimal degrees (J2000)
63- 67 F5.2 mag Ksmagmean [11.24/16.46] Mean Ks-band magnitude
69- 72 F4.2 mag DKsmag [0.22/2.84] Ks variability amplitude ΔKs
74- 76 F3.1 [-] logchi2 [0.5/5.7] Log chi squared (log χ2)
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table5.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 12 A12 --- Name Massive star name
14- 32 A19 --- SpType MK spectral type (1)
34- 51 A18 --- CXOU CXOU identifier; CXOU J(HHMMSS.SS+DDMMSS.S)
53- 58 F6.1 ct NC [3.3/5447.0]? Net X-ray counts in the total
(0.5-8.0 keV) band
60- 62 F3.1 keV ME [0.8/2.4]? Median energy of X-ray photons in
the 0.5-8.0 keV band
64 A1 --- l_PKS [<>] Limit flag on PKS
65- 70 F6.4 % PKS [0.0001/0.05]? X-ray variability probability
PKS (2)
72- 76 F5.2 [cm-2] logNH [18.74/22.48]? Hydrogen column density (3)
78- 83 F6.2 [cm-2] e_logNH [0.02/258.34]? Uncertainty in logNH
85- 89 F5.2 keV kT [0.09/61.04]? kT plasma temperature (3)
91- 97 F7.2 keV e_kT [0/1317.1]? Uncertainty in kT
99-104 F6.2 [mW/m2] logFt [-15.3/0.0]? Log observed X-ray flux
(in erg/s/cm2)
106-109 F4.2 [mW/m2] e_logFt [0.01/1.02]? Uncertainty in logFt
111-116 F6.2 [mW/m2] logFtc [-15.09/0.0]? Log absorption-corrected X-ray
flux (in erg/s/cm2)
118-122 F5.1 --- Chi2 [0/528.8]? Χ2 statistic
124-126 I3 --- dof [0/149]? Degrees of freedom in fit
128 I1 --- Det [0/2]? Detection flag (4)
--------------------------------------------------------------------------------
Note (1): Spectral type from Sana et al. (2006, J/MNRAS/372/661) and
references therein.
Note (2): PKS is the null-hypothesis probability that the flux is constant.
Note (3): Hydrogen column density and plasma temperature parameters from the
wabs*apec model fit.
Note (4): Detection flag as follows:
0 = Star not detected by Chandra;
1 = Star detected by Chandra;
2 = Chandra detection missing X-ray properties.
--------------------------------------------------------------------------------
History:
From electronic version of the journal
References:
Kuhn et al. Paper II. 2017AJ....154..214K 2017AJ....154..214K
(End) Prepared by [AAS], Tiphaine Pouvreau [CDS] 17-Aug-2018