J/ApJ/948/59 Chandra X-ray sources in NGC 3532 with Gaia & WISE (Chen+, 2023)
Population of X-ray sources in the intermediate-age cluster NGC 3532: a test
bed for machine-learning classification.
Chen S., Kargaltsev O., Yang H., Hare J., Volkov I., Rangelov B.,
Tomsick J.
<Astrophys. J., 948, 59 (2023)>
=2023ApJ...948...59C 2023ApJ...948...59C
ADC_Keywords: Clusters, open; X-ray sources; Cross identifications;
Photometry, infrared; Optical; Stars, masses; Stars, ages;
Stars, white dwarf; Surveys
Keywords: Open star clusters ; X-ray sources ; Classification ; Random Forests ;
X-ray stars ; Astronomy data visualization ; Astrostatistics tools ;
X-ray surveys ; Compact objects ; Low mass stars ; Catalogs
Abstract:
Open clusters are thought to be the birthplace of most stars in the
galaxy. Thus, they are excellent laboratories for investigating
stellar evolution, and X-ray properties of various types of stars
(including binary stars, evolved stars, and compact objects). In this
work, we investigate the population of X-ray sources in the nearby
300Myr old open cluster NGC 3532 using Chandra X-ray Observatory and
multiwavelength data from several surveys. We apply a random-forest
machine-learning pipeline (MUWCLASS) to classify all confidently
detected X-ray sources (signal-to-noise ratio, hereafter S/N, >5) in
the field of NGC 3532. We also perform a more detailed investigation
of brighter sources, including their X-ray spectra and lightcurves.
Most X-ray sources are confirmed as coronally active low-mass stars,
many of which are confidently identified by MUWCLASS. Several late B-
or early A-type stars are relatively bright in X-rays, most of which
are likely binaries. We do not find any compact objects among X-ray
sources reliably associated with NGC 3532, down to the limiting X-ray
flux of ∼2x10-15erg/s/cm2, corresponding to LX∼6x1028erg/s at
the cluster's distance. We also identify several Galactic sources
beyond NGC 3532 that differ from typical coronally active stars, and
were classified by MUWCLASS as potential compact objects. Detailed
investigation reveals that these sources may indeed belong to rarer
classes, and deserve follow-up observations.
Description:
Chandra conducted a single observation (ObsID 8941) of NGC 3532 with
the Advanced CCD Imaging Spectrometer (ACIS) from 2008-Oct-23 to
2008-Oct-25 (MJD 54762-54764), for a total of 131,858s (∼36hr).
Objects:
----------------------------------------------------------
RA (ICRS) DE Designation(s)
----------------------------------------------------------
11 05 40.08 -58 42 25.1 NGC 3532 = Cl VDBH 109
----------------------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 78 7 CXO sources without optical or NIR/IR counterparts;
Section 4.3
table2.dat 2663 131 All CXO sources detected with S/N>5; Section 5
table4.dat 67 16 White Dwarfs (WDs) and candidate WDs suggested
to be cluster members of NGC 3532; See Appendix D
--------------------------------------------------------------------------------
See also:
B/chandra : The Chandra Archive Log (CXC, 1999-2014)
VII/233 : 2MASS All-Sky Extended Source Catalog (XSC) (IPAC/UMass, 2003-2006)
II/328 : AllWISE Data Release (Cutri+ 2013)
II/341 : VPHAS+ DR2 survey (Drew+, 2016)
II/363 : The band-merged unWISE Catalog (Schlafly+, 2019)
I/350 : Gaia EDR3 (Gaia Collaboration, 2020)
I/352 : Distances to 1.47 billion stars in Gaia EDR3 (Bailer-Jones+, 2021)
II/365 : CatWISE2020 catalog (updated version 28-Jan-2021) (Marocco+, 2021)
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
IX/70 : Chandra Source Catalog Release 2 (CSC 2.1) (Evans+, 2024)
II/386 : VPHAS+ DR3 survey (Drew+, 2025)
J/ApJS/169/401 : ChaMP X-ray point source catalog (Kim+, 2007)
J/AJ/141/115 : BV(RI)c photometry on NGC 3532 (Clem+, 2011)
J/MNRAS/440/2036 : VPHAS+ survey synthetic colours (Drew+, 2014)
J/ApJS/212/6 : The McGill magnetar catalog (Olausen+, 2014)
J/A+A/581/A28 : Stellar X-ray flares from the 2XMM catalog (Pye+, 2015)
J/MNRAS/457/1988 : White dwarfs in Galactic plane (Raddi+, 2016)
J/A+A/631/A77 : Low-mass stellar models and isochrones (Amard+, 2019)
J/A+A/622/A110 : Spectroscopic membership for NGC 3532 (Fritzewski+, 2019)
J/A+A/628/A41 : KIC stars in Kepler/XMM-Newton (Pizzocaro+, 2019)
J/A+A/652/A60 : Rotation periods for NGC 3532 (Fritzewski+, 2021)
J/ApJ/923/129 : Membership for open clusters with Gaia DR2 (Jaehnig+, 2021)
J/A+A/648/A44 : Large-amplitude variables in Gaia DR2 (Mowlavi+, 2021)
J/ApJ/941/104 : Classification of Chandra sources (Yang+, 2022)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- Seq [17/92] Source sequential number used in
this work
4- 19 A16 --- 2CXO 2CXO Position-based Name from CSC Version 2
21- 23 F3.1 --- Sig [5/7.8] Detection significance
25- 29 A5 --- Class Most probable classification (1)
31- 34 F4.2 --- PClass [0.46/0.93] Probability of classification
36- 39 F4.2 --- e_PClass [0.07/0.3] Uncertainty in PClass
41 A1 --- COc [Y/N] Candidate CO status (2)
43- 46 F4.2 10-17W/m2 Fb [0.45/1.1] Broadband (0.5-7keV) flux,
10-14erg/s/cm2
48- 51 F4.2 10-17W/m2 e_Fb [0.1/0.21] Uncertainty in Fb
53- 57 F5.2 --- HRMS [-0.33/0.85] Hardness ratio, medium-soft
fluxes (Eq. 1a)
59- 62 F4.2 --- e_HRMS [0.1/0.3] Uncertainty in HRMS
64- 67 F4.2 --- HRHM [0.6/0.9] Hardness ratio, hard-medium
fluxes (Eq. 1b)
69- 72 F4.2 --- e_HRHM [0.04/0.11] Uncertainty in HRHM
74- 78 F5.3 --- Pvar [0.013/1] Variability probability
--------------------------------------------------------------------------------
Note (1): Unconfident classifications (as determined by Equation 2)
are marked with "?".
Note (2): Candidate CO status (if CT>2 for CO class probability, see Eq. 2).
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 A4 --- --- [2CXO]
6- 21 A16 --- 2CXO CSC Verion 2 source name
(JHHMMSS.s+DDMMSS)
23- 40 F18.14 deg RAdeg [165.9/166.6]? CSCv2 master
source Right Ascension (J2000)
42- 60 F19.15 deg DEdeg [-59/-58.6]? CSCv2 master
source Declination (J2000)
62- 79 F18.16 arcsec PU [0.2/2.5]? Calculated
positional uncertainty (1)
81- 85 F5.2 --- Sig [5/20.7]? CSCv2 master source
X-ray detection significance
(significance)
87- 108 E22.17 mW.m-2 Fcsc-s [0/0.01]? Reprocessed CSCv2
average soft (0.5-1.2keV)
band flux with symmetric
uncertainties (2)
110- 131 E22.17 mW.m-2 e_Fcsc-s [0/0.01]? 1-sigma Fcsc-s
symmetric Uncertainty (2)
133- 154 E22.17 mW.m-2 Fcsc-m [0/0.01]? Reprocessed CSCv2
average medium (1.2-2keV)
band flux with symmetric
uncertainties (2)
156- 177 E22.17 mW.m-2 e_Fcsc-m [0/0.01]? 1-sigma Fcsc-m
symmetric Uncertainty (2)
179- 200 E22.17 mW.m-2 Fcsc-h [0/0.01]? Reprocessed CSCv2
average hard (2-7keV) band
flux with symmetric
uncertainties (2)
202- 223 E22.17 mW.m-2 e_Fcsc-h [0/0.01]? 1-sigma Fcsc-h
symmetric Uncertainty (2)
225- 246 E22.17 mW.m-2 Fb [0/0.01]? Reprocessed CSCv2
average broad (0.5-7keV) band
flux with symmetric
uncertainties
(flux-aper90-ave-b) (2)
248- 269 E22.17 mW.m-2 e_Fb [0/0.01]? 1-sigma symmetric
uncertainty on Fb
(e_flux-aper90-ave-b) (2)
271- 275 F5.3 --- ProbKpb [0/1]? Intra-observation
Kuiper's test variability
probability (kpintraprob_b)
277- 295 F19.16 --- HRMS [-0.86/0.9]? CXO-based
medium-soft hardness ratio
297- 314 F18.16 --- e_HRMS [0.03/0.5]? 1-sigma CXO
medium-soft hardness ratio
Uncertainty
316- 334 F19.16 --- HRHM [-0.99/0.9]? CXO-based hard-
medium hardness ratio
336- 353 F18.16 --- e_HRHM [0/0.6]? 1-sigma CXO
hard-medium hardness ratio
Uncertainty
355- 363 A9 --- --- [Gaia EDR3]
365- 383 I19 --- GaiaDR3 ? Gaia eDR3 unique identifier
with catalog prefix, Gaia
EDR3 (source_id)
385- 392 A8 --- --- [VPHASDR2 ]
394- 411 A18 --- VPHAS VPHAS+ DR2 unique identifier
(JHHMMSS.s+DDMMSS.s)
(sourceID)
413- 434 E22.17 --- DECaPS2 [4.6e+17/4.9e+17]? DECaPS2
(Saydjari+
2023ApJS..264...28S 2023ApJS..264...28S)
unique identifier (OBJ_ID)
436- 441 A6 --- wOpt Which optical catalog was
used as the counterpart?
443- 449 F7.3 mas.yr-1 pmRA-gaia [-23.1/-4.5]? Gaia eDR3
Proper motion in right
ascension pmRA*cosDE of the
source in ICRS at Ep=2016.0
451- 455 F5.3 mas.yr-1 e_pmRA-gaia [0.01/1.3]? Standard error of
proper motion in right
ascension direction
457- 462 F6.3 mas.yr-1 pmDE-gaia [-3.4/7]? Gaia eDR3 Proper
motion in declination
direction (pmdec)
464- 468 F5.3 mas.yr-1 e_pmDE-gaia [0.01/1.1]? Standard error of
proper motion in declination
direction
470- 476 F7.4 mas Plx-gaia [-2.3/3.5]? Gaia eDR3
Absolute stellar parallax of
the source at the Ep=2016.0
478- 483 F6.4 mas e_Plx-gaia [0/1.3]? Standard error of
the stellar parallax at
Ep=2016.0
485- 502 F18.15 mag Gmag [7.4/22.4]? Gaia eDR3 G band
magnitude, or VPHAS+/DECaPS2
converted equivalent
504- 511 F8.6 mag e_Gmag [0/0.02]? 1-sigma Gmag
uncertainty
513- 530 F18.15 mag BPmag [7.8/23.3]? Gaia eDR3 BP band
magnitude, or VPHAS+/DECaPS2
converted equivalent
532- 539 F8.6 mag e_BPmag [0/0.3]? 1-sigma BPmag
uncertainty
541- 558 F18.15 mag RPmag [6.7/21.7]? Gaia eDR3 RP band
magnitude, or VPHAS+/DECaPS2
converted equivalent
560- 567 F8.6 mag e_RPmag [0/0.4]? 1-sigma RPmag
uncertainty
569- 586 F18.16 mag BP-RP [0.04/3.3]? BPmag-RPmag color
588- 598 F11.6 pc rgeo [286/6089]? Bailer-Jones et
al. (2021) Gaia eDR3 rgeo
distance
600- 610 F11.6 pc e_rgeo [285/5071]? Bailer-Jones et
al. (2021) Gaia eDR3 rgeo
distance lower limit
612- 622 F11.6 pc E_rgeo [287/8181]? Bailer-Jones et
al. (2021) Gaia eDR3 rgeo
distance upper limit
624- 630 A7 --- Memb ? NGC 3532 cluster
membership, determined by
Gaia eDR3 rgeo distance and
proper motion
("NGC3535": 57 occurrences;
or "No")
632- 653 E22.17 W LXb [4e+21/6.9e+24]? X-ray
broadband luminosity using
rgeo distance
(Lum-aper90-ave-b)
655- 676 E22.17 W LumGmag [3.3e+23/2.8e+28]? Gmag
luminosity using rgeo
distance
678- 693 A16 --- 2MASS-eDR3 ? 2MASS source name
crossmatched from Gaia eDR3
precomputed cross-match
catalog (HHMMSSss+DDMMSSs;
J2000)
695- 710 A16 --- 2MASS ? 2MASS source name, manually
crossmatched
(HHMMSSss+DDMMSSs; J2000)
712- 717 F6.3 mag Jmag [6/16.4]? 2MASS J band
magnitude
719- 723 F5.3 mag e_Jmag [0.02/0.5]? 1-sigma Jmag
uncertainty
725- 730 F6.3 mag Hmag [5.5/16]? 2MASS H band
magnitude
732- 736 F5.3 mag e_Hmag [0.02/0.2]? 1-sigma Hmag
uncertainty
738- 743 F6.3 mag Kmag [5.38/15.51]? 2MASS K band
magnitude
745- 749 F5.3 mag e_Kmag [0.01/0.2]? 1-sigma Kmag
uncertainty
751- 769 A19 --- WISEA-eDR3 ? ALLWISE source name
crossmatched from Gaia eDR3
precomputed cross-match
catalog (JHHMMSS.ss+DDMMSS.s)
771- 789 A19 --- WISEA ? ALLWISE source name,
manually crossmatched
(JHHMMSS.ss+DDMMSS.s)
(AllWISE)
791- 809 A19 --- CatWISE ? CatWISE source name
(JHHMMSS.ss+DDMMSS.s)
(source_name)
811- 826 A16 --- unWISE ? UnWISE unique source
identifier (unwise_objid)
828- 834 A7 --- wWISE ? Which WISE catalog was used
as the counterpart?
836- 853 F18.15 mag W1mag [5.36/15.3]? WISE W1 band
magnitude
855- 873 F19.16 mag e_W1mag [-0.02/0.2]? 1-sigma W1mag
uncertainty
875- 892 F18.15 mag W2mag [5.25/16.05]? WISE W2 band
magnitude
894- 912 F19.16 mag e_W2mag [-0.09/0.21]? 1-sigma W2mag
uncertainty
914- 919 F6.3 mag W3mag [5.35/13]? WISE W3 band
magnitude
921- 925 F5.3 mag e_W3mag [0.01/0.3]? 1-sigma W3mag
uncertainty
927- 928 I2 --- cpfl-gaia [-8/0]? Counterpart PU flag
for Gaia (3)
930- 931 I2 --- cpfl-2mass [-8/0]? Counterpart PU flag
for 2mass (3)
933- 934 I2 --- cpfl-catwise [-8/0]? Counterpart PU flag
for CatWISE (3)
936- 937 I2 --- cpfl-unwise [-8/0]? Counterpart PU flag
for UnWISE (3)
939- 940 I2 --- cpfl-allwise [-8/0]? Counterpart PU flag
for ALLWISE (3)
942- 943 I2 --- cpfl-vphas [-8/0]? Counterpart PU flag
for VPHAS+ (3)
945- 948 F4.1 --- cpfl-2mass-g [-8/0]? Counterpart PU flag
for 2MASS Gaia eDR3
precomputed cross-match
catalog (3)
950- 953 F4.1 --- cpfl-wisea-g [-8/0]? Counterpart PU flag
for ALLWISE Gaia eDR3
precomputed cross-match
catalog (cpflag-allwise-gaia)
(3)
955- 958 F4.1 --- cpfl-wise12 [-4/0]? Counterpart PU flag
for WISE catalog used as the
counterpart (3)
960- 963 F4.1 --- cpfl-comb [-4/0]? Combined Counterpart
PU flag (3)
965- 982 F18.16 arcsec sep-gaia [0.07/2.4]? Separation
between CXO and Gaia eDR3
984- 988 F5.3 arcsec sep-2mass [0.03/8.5]? Separation
between CXO and 2MASS
990- 994 F5.3 arcsec sep-catwise [0.02/9.23]? Separation
between CXO and CatWISE
996- 1000 F5.3 arcsec sep-unwise [0.03/9.53]? Separation
between CXO and UnWISE
1002- 1006 F5.3 arcsec sep-allwise [0.02/9.6]? Separation
between CXO and ALLWISE
1008- 1011 F4.2 arcsec sep-vphas [0.02/9.8]? Separation
between CXO and VPHAS+
1013- 1030 F18.16 arcsec sep-decaps [0.05/1.23]? Separation
between CXO and DECaPS2
1032- 1039 A8 --- Class The predicted class of the
source with the highest
classification probability
among eight classes (4)
1041- 1051 F11.9 --- Class-prob [0.28/1]? The classification
probability of the predicted
class calculated from
MUWCLASS
1053- 1058 F6.4 --- e_Class-prob [0/0.37]? 1-sigma Class_prob
Uncertainty
1060- 1079 F20.16 --- CT [0/200]? The classification
confidence threshold
(CT≥2: confidently classified
sources)
1081- 1083 A3 --- COc [Yes/No ] Candidate compact
object (CO) status
1085- 1102 F18.16 --- P-CO [0/0.93]? Classification
probability of the X-ray
source to be classified as a
Candidate CO
1104- 1114 F11.9 --- P-AGN [0/0.98]? Classification
probability of the X-ray
source to be classified as an
AGN
1116- 1126 F11.9 --- P-NS [0/0.9]? Classification
probability of the X-ray
source to be classified as a
NS
1128- 1138 F11.9 --- P-CV [0/0.5]? Classification
probability of the X-ray
source to be classified as a
CV
1140- 1150 F11.9 --- P-LM-STAR [0/1]? Classification
probability of the X-ray
source to be classified as a
LM-STAR
1152- 1162 F11.9 --- P-HM-STAR [0/0.8]? Classification
probability of the X-ray
source to be classified as a
HM-STAR
1164- 1174 F11.9 --- P-LMXB [0/0.8]? Classification
probability of the X-ray
source to be classified as a
LMXB
1176- 1186 F11.9 --- P-HMXB [0/0.4]? Classification
probability of the X-ray
source to be classified as a
HMXB
1188- 1198 F11.9 --- P-YSO [0/0.8]? Classification
probability of the X-ray
source to be classified as a
YSO
1200- 1217 F18.16 --- e_P-CO [0/0.4]? 1-sigma P-CO
Uncertainty
1219- 1224 F6.4 --- e_P-AGN [0/0.4]? 1-sigma P-AGN
Uncertainty
1226- 1231 F6.4 --- e_P-NS [0/0.32]? 1-sigma P-NS
Uncertainty
1233- 1238 F6.4 --- e_P-CV [0/0.2]? 1-sigma P-CV
Uncertainty
1240- 1245 F6.4 --- e_P-LM-STAR [0/0.2]? 1-sigma P-LM-STAR
Uncertainty
1247- 1252 F6.4 --- e_P-HM-STAR [0/0.12]? 1-sigma P-HM-STAR
Uncertainty
1254- 1259 F6.4 --- e_P-LMXB [0/0.23]? 1-sigma P-LMXB
Uncertainty
1261- 1266 F6.4 --- e_P-HMXB [0/0.1]? 1-sigma P-HMXB
Uncertainty
1268- 1273 F6.4 --- e_P-YSO [0/0.2]? 1-sigma P-YSO
Uncertainty
1275- 1284 F10.4 K Teff-gspphot [3248/10039]? Gaia DR3:
Effective temperature from
GSP-Phot Aeneas best library
using BP/RP spectra
1286- 1295 F10.8 Msun Mass-flame [0.54/2.87]? Gaia DR3: Mass
of the star from FLAME using
stellar models, lum_flame,
and teff_gspphot
1297- 1307 F11.8 Gyr Age-flame [0.24/12.5]? Gaia DR3: Age of
the star from FLAME using
stellar models
1309- 1315 A7 --- SpT-esphs ? Gaia DR3: Spectral type
from ESP-ELS
1317- 1319 I3 --- Seq [1/131]? Source sequential
number used in this work
1323- 1336 F14.10 ct NetCts [34/619]? Source net counts
from wavdetect (NET-COUNTS)
1338- 1350 F13.10 ct BkgCts [2/69]? Source background
counts from wavdetect
(BKG-COUNTS)
1352- 1373 E22.17 mW.m-2 flux [0/0.01]? Source flux from
specextract
1375- 1392 F18.16 --- rstat-pl [0.5/1.75]? Powerlaw source
model: fit statistic (5)
1394- 1411 F18.16 --- qval-pl [0/1]? Powerlaw source model:
probability measure (6)
1413- 1430 F18.16 10+22cm-2 gal.nH-pl [0/5.4]? Powerlaw source
model: galactic photoelectric
absorption model hydrogen
column density
1432- 1450 F19.16 10+22cm-2 e_gal.nH-pl [-1.41/-0.04]? Powerlaw
source model: 1-sigma lower
uncertainty on gal.nH-pl
1452- 1469 F18.16 10+22cm-2 E_gal.nH-pl [0.05/1.7]? Powerlaw source
model: 1-sigma upper
uncertainty on gal.nH-pl
1471- 1489 F19.16 --- pl.PhInd [0.67/10]? Powerlaw source
model: source photon index
1491- 1509 F19.16 --- e_pl.PhInd [-3.4/-0.22]? Powerlaw source
model: 1-sigma lower
uncertainty on pl.PhoIndex
1511- 1528 F18.16 --- E_pl.PhInd [0.25/2.7]? Powerlaw source
model: 1-sigma upper
uncertainty on pl.PhoIndex
1530- 1551 E22.17 --- pl.norm [0/0.01]? Powerlaw source
model: normalization
1553- 1576 E24.17 --- e_pl.norm [-0.01/0]? Powerlaw source
model: 1-sigma lower
uncertainty on pl.norm
1578- 1599 E22.17 --- E_pl.norm [0/0.01]? Powerlaw source
model: 1-sigma upper
uncertainty on pl.norm
1601- 1618 F18.16 --- rstat-mek [0.5/1.51]? Mekal source
model: fit statistic (5)
1620- 1637 F18.16 --- qval-mek [0/1]? Mekal source model:
probability measure (6)
1639- 1659 E21.16 10+22cm-2 gal.nH-mek [0/5.2]? Mekal source model:
galactic photoelectric
absorption model hydrogen
column density
1661- 1679 F19.16 10+22cm-2 e_gal.nH-mek [-1.2/-0.05]? Mekal source
model: 1-sigma lower
uncertainty on gal.nH-mekal
1681- 1698 F18.16 10+22cm-2 E_gal.nH-mek [0/2.4]? Mekal source model:
1-sigma upper uncertainty on
gal.nH-mekal
1700- 1718 F19.16 keV mek.kT [0.17/80]? Mekal source
model: source plasma
temperature
1720- 1739 F20.16 keV e_mek.kT [-70/-0.02]? Mekal source
model: 1-sigma lower
uncertainty on mek.kT
1741- 1759 F19.16 keV E_mek.kT [0.02/39]? Mekal source
model: 1-sigma upper
uncertainty on mek.kT
1761- 1782 E22.17 --- mek.norm [0/0.01]? Mekal source model:
normalization
1784- 1807 E24.17 --- e_mek.norm [-0.01/0]? Mekal source
model: 1-sigma lower
uncertainty on mek.norm
1809- 1830 E22.17 --- E_mek.norm [0/0.01]? Mekal source model:
1-sigma upper uncertainty on
mek.norm
1832- 1849 F18.16 --- rstat-2mek [0.74/1.15]? Two component
Mekal source model: fit
statistic (5)
1851- 1868 F18.16 --- qval-2mek [0.14/0.98]? Two component
Mekal source model:
probability measure (6)
1870- 1887 F18.16 10+22cm-2 gal.nH_2mek [0.004/0.6]? Two component
Mekal source model: galactic
photoelectric absorption
model hydrogen column density
1889- 1907 F19.16 10+22cm-2 egal.nH2mek [-0.24/-0.1]? Two component
Mekal source model: 1-sigma
lower uncertainty on
gal.nH_twomekal
1909- 1926 F18.16 10+22cm-2 Egal.nH2mek [0.1/0.8]? Two component
Mekal source model: 1-sigma
upper uncertainty on
gal.nH_twomekal
1928- 1945 F18.16 keV mek1.kT [0.2/0.4]? Two component
Mekal source model: source
component 1 plasma
temperature
1947- 1965 F19.16 keV e_mek1.kT [-0.2/-0.03]? Two component
Mekal source model: 1-sigma
lower uncertainty on mek1.kT
1967- 1984 F18.16 keV E_mek1.kT [0.04/0.08]? Two component
Mekal source model: 1-sigma
upper uncertainty on mek1.kT
1986- 2003 F18.16 keV mek2.kT [1.27/2.6]? Two component
Mekal source model: source
component 2 plasma
temperature
2005- 2023 F19.16 keV e_mek2.kT [-0.83/-0.19]? Two component
Mekal source model: 1-sigma
lower uncertainty on mek2.kT
2025- 2042 F18.16 keV E_mek2.kT [0.28/3.1]? Two component
Mekal source model: 1-sigma
upper uncertainty on mek2.kT
2044- 2064 E21.16 --- mek1.norm [5.5e-06/0.0003]? Two
component Mekal source model:
component 1 normalization
2066- 2088 E23.16 --- e_mek1.norm [-0.00014/-2.2e-05]? Two
component Mekal source model:
1-sigma lower uncertainty on
mek1.norm
2090- 2107 F18.16 --- E_mek1.norm [0.00014/0.001]? Two
component Mekal source model:
1-sigma upper uncertainty on
mek1.norm
2109- 2130 E22.17 --- mek2.norm [1e-05/1.9e-05]? Two
component Mekal source model:
component 2 normalization
2132- 2155 E24.17 --- e_mek2.norm [-2.94e-06/-1.8e-06]? Two
component Mekal source model:
1-sigma lower uncertainty on
mek2.norm
2157- 2178 E22.17 --- E_mek2.norm [2e-06/8.2e-06]? Two
component Mekal source model:
1-sigma upper uncertainty on
mek2.norm
2180- 2184 F5.1 ct FlareCts [28/495]? Flare source counts
(flare-counts)
2186- 2207 E22.17 mW.m-2 Fflare-mek [2.78e-14/1.43e-13]? Flare
source flux (flux-flare-mekal)
2209- 2226 F18.16 --- rstat-flare-pl [0.6/1.8]? Flare powerlaw
source model: fit statistic
(5)
2228- 2245 F18.16 --- qval-flare-pl [0.02/1]? Flare powerlaw
source model: probability
measure (6)
2247- 2264 F18.16 10+22cm-2 gal.nH_flare-pl [0.0008/0.9]? Flare powerlaw
source model: galactic
photoelectric absorption
model hydrogen column density
2266- 2284 F19.16 10+22cm-2 egal.nHflare-pl [-0.7/-0.1]? Flare powerlaw
source model: 1-sigma lower
uncertainty on
gal.nH_flare-pl
2286- 2303 F18.16 10+22cm-2 Egal.nHflare-pl [0.1/1.1]? Flare powerlaw
source model: 1-sigma upper
uncertainty on
gal.nH_flare-pl
2305- 2322 F18.16 --- pl.PhInd-flare-pl [1.3/5.5]? Flare powerlaw
source model: source photon
index (pl.PhoIndex-flare-pl)
2324- 2342 F19.16 --- e_pl.PhInd-flare-pl [-2.5/-0.24]? Flare powerlaw
source model: 1-sigma lower
uncertainty on
pl.PhoIndex_flare-pl
2344- 2361 F18.16 --- E_pl.PhInd-flare-pl [0.3/4]? Flare powerlaw
source model: 1-sigma upper
uncertainty on
pl.PhoIndex_flare-pl
2363- 2384 E22.17 --- pl.norm-flare-pl [8.8e-06/0.0003]? Flare
powerlaw source model:
normalization
2386- 2409 E24.17 --- e_pl.norm-flare-pl [-0.0002/-2.29e-06]? Flare
powerlaw source model:
1-sigma lower uncertainty on
pl.norm_flare-pl
2411- 2432 E22.17 --- E_pl.norm-flare-pl [8.18e-06/0.004]? Flare
powerlaw source model:
1-sigma upper uncertainty on
pl.norm_flare-pl
2434- 2451 F18.16 --- rstat-flare-mek [0.6/2.4]? Flare mekal source
model: fit statistic (5)
2453- 2470 F18.16 --- qval-flare-mek [0.0003/1]? Flare mekal
source model: probability
measure (6)
2472- 2492 E21.16 10+22cm-2 gal.nH_flare-mek [0/1.6]? Flare mekal source
model: galactic photoelectric
absorption model hydrogen
column density
2494- 2512 F19.16 10+22cm-2 egal.nHflare-mek [-0.51/-0.1]? Flare mekal
source model: 1-sigma lower
uncertainty on
gal.nH_flare-mekal
2514- 2531 F18.16 10+22cm-2 Egal.nHflare-mek [0.03/1.3]? Flare mekal
source model: 1-sigma upper
uncertainty on
gal.nH_flare-mekal
2533- 2551 F19.16 keV mek.kT_flare-mek [0.42/16.1]? Flare mekal
source model: source plasma
temperature
2553- 2572 F20.16 keV emek.kTflare-mek [-12.9/-0.06]? Flare mekal
source model: 1-sigma lower
uncertainty on
mek.kT_flare-mekal
2574- 2592 F19.16 keV Emek.kTflare-mek [0.08/11.4]? Flare mekal
source model: 1-sigma upper
uncertainty on
mek.kT_flare-mekal
2594- 2615 E22.17 --- mek.norm-flare-mek [2.3e-05/0.0004]? Flare mekal
source model: normalization
2617- 2640 E24.17 --- e_mek.norm-flare-mek [-0.0003/-4.4e-06]? Flare
mekal source model: 1-sigma
lower uncertainty on
mek.norm_flare-mekal
2642- 2663 E22.17 --- E_mek.norm-flare-mek [6.8e-06/0.12]? Flare mekal
source model: 1-sigma upper
uncertainty on
mek.norm_flare-mekal
--------------------------------------------------------------------------------
Note (1): Positional uncertainty based on errellipser0 from CSCv2
calculated using the empirical Equation 12 from Kim+ 2007, J/ApJS/169/401
Note (2): The CSCv2 fluxes fluxaper90avg_s, fluxaper90avg_m,
fluxaper90avg_h, fluxaper90avg_b and their assymmetric
uncertainties were reprocessed to have symmetric flux
uncertainties for ML classification purposes, following the
equations in Possolo+ 2019Metro..56d5009P 2019Metro..56d5009P
Note (3): Counterpart flags as follows:
0 = counterpart found within combined PU;
-4 = counterpart found within 1.5 times combined PU;
-8 = counterpart outside 1.5 times combined PU.
Note (4): Class as follows:
AGN = active galactic nucleus (7 occurrences)
AGN? = uncertain AGN classification (5 occurrences)
LM-STAR = low-mass star, up to late B-type (40 occurrences)
LM-STAR? = uncertain LM-STAR classification (16 occurrences)
HM-STAR = high-mass star (2 occurrences)
YSO = protostars and pre-main-sequence stars (9 occurrences)
YSO? = uncertain YSO classification (22 occurrences)
LMXB = low-mass X-ray binary (2 occurrences)
LMXB? = uncertain LMXB classification (12 occurrences)
HMXB? = uncertain high-mass X-ray binary classification (1 occurrence)
CV? = uncertain cataclysmic variable classification (10 occurrences)
NS = Neutron star, isolated (1 occurrence)
NS? = uncertain NS classification (4 occurrences)
Note (5): rstat is the model fit statistic value (wstat) divided by
the number of degrees of freedom.
Note (6): qval is measure of the probability that one would observe
the reduced statistic value, or a larger value, if the assumed
model is true and the best-fit model parameters are the true
parameter values
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 1 I1 --- Field [0/1] 1=WD in the CXO field of NGC3532
3- 26 A24 --- Name Identifier
28- 40 A13 --- Type Object Type
42- 52 F11.7 deg RAdeg [165.8/168.3] Right Ascension (J2000)
54- 65 F12.8 deg DEdeg [-59.1/-58.3] Declination (J2000)
67- 67 I1 --- Ref [1/3] Reference (1)
--------------------------------------------------------------------------------
Note (1): References as follows:
1 = Dobbie+ 2012MNRAS.423.2815D 2012MNRAS.423.2815D
2 = Raddi+ 2016, J/MNRAS/457/1988
3 = Koester & Reimers 1993A&A...275..479K 1993A&A...275..479K
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 06-May-2025