J/ApJS/213/1 The MSFRs Omnibus X-ray Catalog (MOXC) (Townsley+, 2014)
The Massive Star-Forming Regions Omnibus X-ray Catalog.
Townsley L.K., Broos P.S., Garmire G.P., Bouwman J., Povich M.S.,
Feigelson E.D., Getman K.V., Kuhn M.A.
<Astrophys. J. Suppl. Ser., 213, 1 (2014)>
=2014ApJS..213....1T 2014ApJS..213....1T
ADC_Keywords: X-ray sources ; H II regions
Keywords: ISM: individual (NGC 6334, NGC 6357, M16, M17, W3, W4, NGC 3576,
G333.6-0.2, W51A, G29.96-0.02, NGC 3603, 30 Doradus);
open clusters and associations: individual (Pismis 24,
AH03 J1725-34.4, NGC 6611, NGC 6618, W3 Main, W3(OH), IC 1795,
IC 1805, OCl 352, G49.5-0.4, R136, NGC 2060); stars: early-type;
stars: formation; stars: individual (Pismis 24-1, Pismis 24-17, WR 93,
[N78] 49, HD 168076, NGC 6611 213, CEN1a, CEN1b, Cl* NGC 6618 Sch 1,
HD 15558, EM Car, W51 IRS2E, NGC 3603-A1, NGC 3603-B, NGC 3603-C,
Cl* NGC 3603 Sher 47, WR 42e, MTT 58, MTT 68, Mk34, R140a1a2);
X-rays: stars
Abstract:
We present the Massive Star-forming Regions (MSFRs) Omnibus X-ray
Catalog (MOXC), a compendium of X-ray point sources from Chandra/ACIS
observations of a selection of MSFRs across the Galaxy, plus
30 Doradus in the Large Magellanic Cloud. MOXC consists of 20623 X-ray
point sources from 12 MSFRs with distances ranging from 1.7kpc to
50kpc. Additionally, we show the morphology of the unresolved X-ray
emission that remains after the cataloged X-ray point sources are
excised from the ACIS data, in the context of Spitzer and WISE
observations that trace the bubbles, ionization fronts, and
photon-dominated regions that characterize MSFRs. In previous work, we
have found that this unresolved X-ray emission is dominated by hot
plasma from massive star wind shocks. This diffuse X-ray emission is
found in every MOXC MSFR, clearly demonstrating that massive star
feedback (and the several-million-degree plasmas that it generates) is
an integral component of MSFR physics.
Description:
The Chandra observations used for the Massive Star-forming Regions
Omnibus X-ray Catalog (MOXC) are summarized in Table 2 and are ranging
from 2000-04-03 to 2013-01-31 for the 12 massive star-forming regions
(MSFRs).
A similar table than table3 for other MYStIX targets was presented by
Kuhn et al. (2013, Cat. J/ApJS/209/27). The main difference between
that and the MOXC version (Table 3) is that we have chosen to omit
absorption-corrected X-ray source luminosities from the XPHOT
algorithm (Getman et al. 2010, Cat. J/ApJ/708/1760) here, because
those quantities are given in Broos et al. (2013, Cat. J/ApJS/209/32)
for relevant MYStIX X-ray sources (those classified as pre-MS stars).
For beyond-MYStIX targets, we choose to postpone XPHOT calculations
until the X-ray sources are classified, since XPHOT estimates are only
appropriate for pre-MS stars. The XPHOT code is available (Getman et
al. 2012ascl.soft12002G) if others wish to use it on MOXC sources. See
section 3.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 124 12 MOXC targets
table2.dat 132 48 Log of Chandra ACIS-I observations
table3.dat 400 20623 MOXC X-ray sources and properties
table4.dat 85 80 Sources exhibiting photon pile-up
table6.dat 46 10569 MOXC sources in published Chandra catalogs
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See also:
B/chandra : The Chandra Archive Log (CXC, 1999-2014)
B/ocl : Optically visible open clusters and Candidates (Dias+ 2002-2013)
J/ApJS/209/32 : Probable young stars in the MYStIX project (Broos+, 2013)
J/ApJS/209/31 : The MYStIX IR-Excess Source catalog (MIRES) (Povich+, 2013)
J/ApJS/209/30 : MYStIX project: Bayesian matching (Naylor+, 2013)
J/ApJS/209/29 : MYStIX: Mid-IR 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/A+A/552/A123 : Far-IR study of G29.96-0.02 (Beltran+, 2013)
J/A+A/538/A142 : OB stars in NGC 6334 and NGC 6357 (Russeil+, 2012)
J/ApJ/753/117 : X-ray catalog of Eagle Nebula (Guarcello+, 2012)
J/ApJ/743/39 : Spitzer obs. of W3 molecular cloud (Rivera-Ingraham+, 2011)
J/ApJ/733/113 : IRAC observations of IC 1795 (Roccatagliata+, 2011)
J/A+A/526/A151 : Hi-Gal sources distance determination (Russeil+, 2011)
J/ApJS/194/15 : CCCP: Carina's diffuse X-ray emission (Townsley+, 2011)
J/ApJS/194/9 : X-ray star clusters in the Carina complex (Feigelson+, 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/725/2485 : X-rays from the star-forming complex W40 (Kuhn+, 2010)
J/ApJ/708/1760 : Flux estimations of faint X-ray sources (Getman+, 2010)
J/A+A/521/A61 : Stars associated to Eagle Nebula (M16) (Guarcello+ 2010)
J/A+A/515/A55 : NGC 6334-NGC 6357 complex (Russeil+, 2010)
J/AJ/138/227 : Stellar clusters in NGC 6334 complex (Feigelson+, 2009)
J/ApJ/696/1278 : The extended star-forming environment of M17 (Povich+, 2009)
J/ApJ/675/1319 : Infrared photometry of NGC 3603 (Harayama+, 2008)
J/AJ/136/2083 : NGC 6334 clumps from 450/850um observations (Matthews+, 2008)
J/ApJ/668/906 : Massive clumps in NGC 6334 (Munoz+, 2007)
J/ApJ/654/347 : Chandra X-ray obs. in Eagle Nebula. I. (Linsky+, 2007)
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/MNRAS/379/663 : 850um observations of W3 giant molecular cloud (Moore+, 2007)
J/AJ/131/2164 : X-ray sources in RMC 136 (Townsley+, 2006)
J/AJ/129/393 : UBV photometry in W3 (Oey+, 2005)
J/ApJS/160/319 : COUP: observations and source lists (Getman+, 2005)
J/AJ/127/1014 : CCD UBVRIHa photometry in NGC 3603 (Sung+, 2004)
J/A+A/404/223 : 2MASS IR star clusters in the Galaxy (Bica+, 2003)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1 A1 --- f_Region [B] B: Beyond MYStIX; blank if MYStIX
3- 14 A12 --- Region MOXC target
16- 21 F6.2 deg GLON Galactic longitude
23- 28 F6.2 deg GLAT Galactic latitude
30- 31 I2 h RAh Hour of right ascension (J2000)
33- 34 I2 min RAm Minute of right ascension (J2000)
36- 39 F4.1 s RAs Second of right ascension (J2000)
41 A1 --- DE- Sign of declination (J2000)
42- 43 I2 deg DEd Degree of declination (J2000)
45- 46 I2 arcmin DEm Arcminute of declination (J2000)
48- 49 I2 arcsec DEs Arcsecond of declination (J2000)
51- 55 F5.2 kpc Dist [1.7/50] Distance (1)
57- 60 F4.2 arcmin/pc Scale [0.07/2.1] Scale (2)
62- 65 F4.1 mag <Av> [0.5/21] Average absorption (3)
67- 69 I3 s Exp [27/490] Nominal exposure time
71- 75 F5.2 [10-7W] logLtc [29.2/32.2] limiting luminosity Ltc
("total" band 0.5-8keV, corrected for
extinction)
77- 79 F3.1 Msun M50 ? The mass at which Ltc captures the
brighter half of the X-ray-emitting
population (M50%)
80 A1 --- f_M50 [b] b: bright
82- 85 I4 --- Nx [172/3885] Number of X-ray sources (table3)
87-124 A38 --- r_Dist Distance reference (author and bibcode)
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Note (1): Distances for MYStIX targets are taken from Feigelson et al.
(2013ApJS..209...26F 2013ApJS..209...26F); primary references are given there.
Note (2): Image scale assuming the distance given in Column "Dist".
Note (3): Approximate average absorption to the target, estimated from a variety
of literature sources. Most MSFRs have highly variable and spatially
complex obscuration, so this value should be used only as a rough
indicator.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 12 A12 --- Region Massive Star-forming Region (MSFR) name
14- 30 A17 --- Target Original target name
32- 36 I5 --- ObsID Chandra observation identification number
38- 43 I6 --- Seq Sequence number (shows which ObsIDs make up a
single ACIS pointing)
45- 60 A16 "datime" Time Start time (UT)
62- 67 I6 s Exp [1015/165185] Exposure time (1)
69- 70 I2 h RAh Aimoint hour of right ascension (J2000) (2)
72- 73 I2 min RAm Aimoint minute of right ascension (2)
75- 79 F5.2 s RAs Aimoint second of right ascension (2)
81 A1 --- DE- Aimpoint sign of declination (J2000) (2)
82- 83 I2 deg DEd Aimpoint degree of declination (J2000) (2)
85- 86 I2 arcmin DEm Aimpoint arcminute of declination (2)
88- 91 F4.1 arcsec DEs Aimpoint arcsecond of declination (2)
93- 95 I3 deg Roll [72/352] Roll angle
97-108 A12 --- Mode ACIS observing mode (3)
110-126 A17 --- PI Principal Investigator
128-132 A5 --- CALDB Chandra Calibration Database version used
for event calibration
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Note (1): Exposure times are the net usable times after various filtering steps
are applied in the data reduction process. For the following ObsIDs,
we discarded exposure time as noted to remove periods of high
instrumental background: 2573 (16ks), 13267 (0.4ks), 6422 (9ks),
7391 (0.7ks), 8461 (0.6ks), 5891 (0.5ks), 7033 (1ks), 4496 (0.4ks),
6349 (9ks), 2524 (1ks), and 633 (3ks). The time variability of the
ACIS background is discussed in Section 6.16.3 of the Chandra
Proposers' Observatory Guide (http://asc.harvard.edu/proposer/POG/)
and in the ACIS Background Memos at
http://asc.harvard.edu/cal/Acis/Cal_prods/bkgrnd/current/.
Note (2): The aimpoints (given in celestial coordinates) are obtained from the
satellite aspect solution before astrometric correction is applied.
Note (3): ACIS observing modes are described in Section 6.12 of the Chandra
Proposers' Observatory Guide.
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Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 12 A12 --- Region Massive Star-forming Region (MSFR) name
14- 31 A18 --- CXOU X-ray source name in IAU format
(HHMMSS.ss+DDMMSS.s; J2000)
33- 43 A11 --- Label X-ray source name used in the project (G1)
45- 54 F10.6 deg RAdeg Right ascension (J2000)
56- 65 F10.6 deg DEdeg Declination (J2000)
67- 70 F4.2 arcsec ePos [0/2.5] 1-σ error circle around (RA,DE)
72- 88 A17 --- PosType Algorithm used to estimate position (2)
90- 95 F6.4 --- no-m [0/0.01] Merged p-value for no-source
hypothesis (smallest of no-t/no-s/no-h)
97-102 F6.4 --- no-t [0/0.4] p-value for 0.5-8keV no-source
hypothesis (3)
104-109 F6.4 --- no-s ? p-value for 0.5-2keV no-source hypothesis (3)
111-116 F6.4 --- no-h ? p-value for 2-8keV no-source hypothesis (3)
118-123 F6.4 --- KS_S ? Smallest p-value under the no-variability
null hypothesis within a single-observation for
one-sample Kolmogorov-Smirnov statistic (4)
125-130 F6.4 --- KS_M ? Smallest p-value under the no-variability
null hypothesis over merged observations for
one-sample Kolmogorov-Smirnov statistic (4)
132-139 F8.1 s ExpNom [11660/494630] Total exposure time in merged
observations
141-144 F4.2 --- ExpFrac [0/1] Fraction of ExpNom source was observed
146-152 F7.5 ct Ct [0/0.6] 0.5-8keV rate in 3x3 CCD pixel cell
in count/frame (RateIn3x3Cell) (5)
154 I1 --- Nobs [1/9] Total number of observations extracted
156 I1 --- Nph [1/9] Number of observations merged to
estimate photometry properties
158-161 F4.2 --- Fdis [0/1] Fraction of exposure discarded in merge
163-167 F5.2 arcmin b_theta Smallest value of θ
169-173 F5.2 arcmin theta Average off-axis angle θ for merged
observations
175-179 F5.2 arcmin B_theta Largest value of θ
181-184 F4.2 --- PSFf [0.3/1] Average PSF fraction at 1.5keV for
merged observations
186-192 F7.2 --- Area [1/2146] Average aperture area for merged
observations in (0.492arcsec)2 units
194-197 F4.2 --- aglow [0/0.7]? Suspected afterglow fraction (6)
199-203 I5 ct Oct-t [1/31170] Observed 0.5-8keV counts in merged
apertures
205-209 I5 ct Oct-s Observed 0.5-2keV counts in merged apertures
211-215 I5 ct Oct-h Observed 2-8keV counts in merged apertures
217-222 F6.1 --- bgScl Scaling of background extraction
224-228 I5 ct bgct-t [0/10377] Observed 0.5-8keV counts in merged
background regions
230-233 I4 ct bgct-s Observed 0.5-2keV counts in merged background
regions
235-238 I4 ct bgct-h Observed 2-8keV counts in merged background
regions
240-246 F7.1 ct Nct-t [0.2/30101] Net 0.5-8keV counts in merged
apertures
248-254 F7.1 ct Nct-s Net 0.5-2keV counts in merged apertures
256-262 F7.1 ct Nct-h Net 2-8keV counts in merged apertures
264-270 F7.1 ct b_Nct-t 1σ lower bound on NCt-t (7)
272-278 F7.1 ct B_Nct-t 1σ upper bound on NCt-t (7)
280-286 F7.1 ct b_Nct-s ? 1σ lower bound on NCt-s (7)
288-294 F7.1 ct B_Nct-s 1σ upper bound on NCt-s (7)
296-302 F7.1 ct b_Nct-h ? 1σ lower bound on NCt-h (7)
304-310 F7.1 ct B_Nct-h 1σ upper bound on NCt-h (7)
312-317 F6.2 cm2 Area-t [30/246] Mean effective area (ARF value) in
cm2.count/photon in 0.5-8keV (8)
319-324 F6.2 cm2 Area-s Mean effective area (ARF value) in
cm2.count/photon in 0.5-2keV (8)
326-331 F6.2 cm2 Area-h Mean effective area (ARF value) in
cm2.count/photon in 2-8keV (8)
333-336 F4.2 keV E-t [0.5/7] Median 0.5-8keV energy, observed
spectrum (9)
338-341 F4.2 keV E-s ? Median 0.5-2keV energy, observed spectrum (9)
343-346 F4.2 keV E-h ? Median 2-8keV energy, observed spectrum (9)
348-356 E9.3 ph/cm2/s XFlx-t Apparent photon flux in total (0.5-8keV) band
(10)
358-366 E9.3 ph/cm2/s XFlx-s Apparent photon flux in soft (0.5-2keV) band
368-376 E9.3 ph/cm2/s XFlx-h Apparent photon flux in hard (2-8keV) band
378-384 E7.2 mW/m2 EFlx-t Apparent energy flux in total (0.5-8keV) band
(max(EFlx-s,0)+max(EFlx-h,0))
386-392 E7.2 mW/m2 EFlx-s ? Apparent energy flux in soft (0.5-2keV)
band (11)
394-400 E7.2 mW/m2 EFlx-h ? Apparent energy flux in hard (2-8keV) band
(11)
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Note (2): Algorithm used to estimate position as in Broos et al.
2010ApJ...714.1582B 2010ApJ...714.1582B, Section 7. The algorithm is one of
"AE correlation", "AE mean dataC", "AE reconstruction", orr "eye"
Note (3): 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 (4): 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 (5): ACIS suffers from a nonlinearity at high count rates known as photon
pile-up, described in Section 3.2. "Rate" is an estimate of the
observed count rate falling on an event detection cell of size 3x3
ACIS pixels, centered on the source position. When "Rate">0.05 (count
per frame), the reported source properties may be biased by pile-up
effects. See Table 4 for a list of MOXC sources with significant
pile-up.
Note (6): 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 AE 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 (7): Confidence intervals (68%) for NetCounts quantities are estimated by
the CIAO tool aprates
(http://asc.harvard.edu/ciao/ahelp/aprates.html).
Note (8): 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
(ExpFra).
Note (9): The median energy of extracted events, corrected for background
(Broos et al. 2010ApJ...714.1582B 2010ApJ...714.1582B, Section 7.3).
Note (10): XFlx-t=(NCt-t/Area-t/ExpNom) (Broos et al. 2010ApJ...714.1582B 2010ApJ...714.1582B,
Section 7.4).
Note (11): EFlx-s=1.602x10-9(erg/keV)x(NCt/ExpNom/Area-s)xE-s
(Getman et al. 2010, Cat. J/ApJ/708/1760, Section 2.2).
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Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 12 A12 --- Region MSFR name (as in table3)
14- 31 A18 --- CXOU X-ray source name in IAU format
(HHMMSS.ss+DDMMSS.s; J2000)
33- 39 A7 --- Label X-ray source name used in the project (G1)
41- 64 A24 --- OName Source name from VizieR or SIMBAD
66- 70 I5 --- ObsID Chandra observation identification number
72- 74 F3.1 arcmin theta [0.2/6.5] Off-axis angle θ
76- 79 F4.2 --- PSFf [0.4/1] Fraction of the PSF (at 1.497keV)
enclosed within the extraction region (1)
81- 85 F5.3 --- Corr [1/1.9]? Estimated ratio of pile-up-free to
observed (piled) count rates in the 0.5-8keV
energy band
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Note (1): A reduced PSF fraction (significantly below 90%) indicates that the
source is in a crowded region.
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 18 A18 --- CXOU MOX Catalog identifier (HHMMSS.ss+DDMMSS; J2000)
20- 23 I4 --- Seq ?=-99 Published Chandra catalog sequence
identifier
25- 42 A18 --- CXO ? Published Chandra catalog identifier (1)
44- 46 F3.1 arcsec Offset ? Offset between MOXC and published positions
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Note (1): Previously published Chandra Catalogs of MOXC targets are (table 5):
-----------------------------------------------------------------------------
Target Reference Astrometric offset
RAJ2000 DEJ2000
(arcsec)
-----------------------------------------------------------------------------
NGC 6334 Feigelson et al. (2009, Cat. J/AJ/138/227) 0.01 0.02
NGC 6357 Wang et al. (2007, Cat. J/ApJS/168/100) 0.06 0.01
Eagle Nebula Guarcello et al. (2012, Cat. J/ApJ/753/117) -0.06 0.01
M17 Broos et al. (2007, Cat. J/ApJS/169/353) 0.01 0.03
30 Doradus Townsley et al. (2006, Cat. J/AJ/131/2164) -0.09 0.13
-----------------------------------------------------------------------------
Astrometric offsets are the adjustment to the published coordinates required
for best alignment with the MOXC coordinates.
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Global note:
Note (G1): Source labels identify a Chandra pointing; they do not convey
membership in astrophysical clusters.
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History:
From electronic version of the journal
References:
Townsley et al. MOXC2. 2018ApJS..235...43T 2018ApJS..235...43T Cat. J/ApJS/235/43
Townsley et al. MOXC3. 2019ApJS..244...28T 2019ApJS..244...28T Cat. J/ApJS/244/28
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 27-Aug-2014