J/ApJS/179/142 Catalog of X-ray sources in NGC 3379 (Brassington+, 2008)
Deep Chandra monitoring observations of NGC 3379: catalog of source properties.
Brassington N.J., Fabbiano G., Kim D.-W., Zezas A., Zepf S., Kundu A.,
Angelini L., Davies R.L., Gallagher J., Kalogera V., Fragos T., King A.R.,
Pellegrini S., Trinchieri G.
<Astrophys. J. Suppl. Ser., 179, 142-165 (2008)>
=2008ApJS..179..142B 2008ApJS..179..142B
ADC_Keywords: X-ray sources
Keywords: galaxies: individual (NGC 3379) - X-rays: binaries - X-rays: galaxies
Abstract:
We present the properties of the discrete X-ray sources detected in
our monitoring program of the 'typical' elliptical galaxy, NGC 3379,
observed with Chandra ACIS-S in five separate pointings, resulting in
a co-added exposure of 324ks. From this deep observation, 132 sources
have been detected within the region overlapped by all observations,
98 of which lie within the D25 ellipse of the galaxy. These 132
sources range in LX from 6x1035erg/s (with 3σ upper limit
≤4x1036erg/s) to ∼2x1039erg/s, including one source with
LX>1x1039erg/s, which has been classified as an ULX. From optical
data, 10 X-ray sources have been determined to be coincident with a
globular cluster, these sources tend to have high X-ray luminosity,
with three of these sources exhibiting LX>1x1038erg/s. From X-ray
source photometry, it has been determined that the majority of the 132
sources that have well constrained colors, have values that are
consistent with typical LMXB spectra. In addition to this, a
subpopulation of 10 sources has been found to exhibit very hard
spectra and it is expected that most of these sources are absorbed
background AGN. There are 64 sources in this population that exhibit
long-term variability, indicating that they are accreting compact
objects. Five of these sources have been identified as transient
candidates, with a further 3 possible transients. Spectral variations
have also been identified in the majority of the source population,
where a diverse range of variability has been identified, indicating
that there are many different source classes located within this
galaxy.
Description:
The five separate Chandra observations of NGC 3379 have been carried
out over a 6yr baseline, with the first of these, a 30ks pointing,
performed in 2001 February. This observation was followed by four
deeper pointings, all carried out between 2006 January and 2007
January, resulting in a total exposure time of 337ks.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4.dat 107 132 Master Source List
table5.dat 144 132 Source counts, hardness ratios and color-color
values: Coadded Observation
table6.dat 150 132 Source counts, hardness ratios, color-color
values and variability: Observation 1
table7.dat 150 132 Source counts, hardness ratios, color-color
values and variability: Observation 2
table8.dat 150 132 Source counts, hardness ratios, color-color
values and variability: Observation 3
table9.dat 150 132 Source counts, hardness ratios, color-color
values and variability: Observation 4
table10.dat 150 132 Source counts, hardness ratios, color-color
values and variability: Observation 5
table15.dat 80 132 Raw source and background counts from the
co-added observation
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See also:
B/chandra : The Chandra Archive Log (CXC, 2002)
J/ApJ/635/1053 : X-ray sources in NGC 3379 (David+, 2005)
Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1 A1 --- n_[BFK2008] [<>] Indicates detection with SNR < or > 3
3- 5 I3 --- [BFK2008] Master identification number
7 A1 --- f_[BFK2008] [b] source within optical limits (1)
9- 24 A16 --- CXOU IAU identification (JHHMMSS.s+DDMMSS) (2)
26- 27 I2 h RAh Hour of Right Ascension (J2000)
29- 30 I2 min RAm Minute of Right Ascension (J2000)
32- 35 F4.1 s RAs Second of Right Ascension (J2000)
37 A1 --- DE- Sign of the Declination (J2000)
38- 39 I2 deg DEd Degree of Declination (J2000)
41- 42 I2 arcmin DEm Arcminute of Declination (J2000)
44- 47 F4.1 arcsec DEs Arcsecond of Declination (J2000)
49- 52 F4.2 arcsec Rad Source extraction radius
54- 57 F4.2 arcsec e_pos ? Position uncertainty; see Eq.1
59- 62 F4.1 --- SNR ? Signal-to-Noise ratio
64- 65 A2 --- l_logLX [≤ ] Limit flag on logLX
66- 69 F4.1 [10-7W] logLX Log of 0.3-8.0keV luminosity (3)
71- 72 A2 --- l_3logLX Limit flag on logLX
73- 76 F4.1 [10-7W] 3logLX ? The 3σ uncertainty in logLX (3)
78- 80 A3 --- LT Long-term source variability (4)
82 A1 --- BB Short-term variability from Bayesian block
analysis (5)
84 A1 --- K-S Short-term variability from
Kolmogorov-Smirnov test (5)
86- 91 A6 --- Opt Optical association (6)
93- 97 F5.1 arcsec DG Distance from center of galaxy
99 A1 --- n_DG [b] source within optical limits (1)
101-107 A7 --- Note Additional information (7)
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Note (1): b = source is within the D25 ellipse of the galaxy
(duplicated column)
Note (2): Following the convention "CXOU Jhhmmss.s±ddmmss".
[BFK2008] JHHMMSS.s+DDMMSS in Simbad.
Note (3): Assuming D=10.6Mpc. For sources only detected in a single observation,
1σ upper limits from the co-added observation are quoted (with
3σ upper limits from the detected observation following.
Note (4): Long-term variability as follows:
N = non-variable source;
V = variable source;
TC = transient candidate;
PTC = possible transient.
Note (5): Short-term variability as follows:
N = non-variable in all observations;
V = variable in at least one observation;
P = possible variability in at least one observation.
Note (6): Optical association as follows:
GC = optical source is a confirmed globular cluster;
BG = optical source is a background object;
corr = match has been defined as correlationed;
exmt = match between 0.6" and 3" in separation;
none = source inside the field of view of the HST observation, but has no
optical counterpart;
X = source within the HST FOV but also within 5" of the nucleus.
Note (7): Note as follows:
X = source detected in a single observation only,
O1 = single overlapping source;
O2 = complicated overlapping sources;
BKG? = possible background object;
double? = possible double source.
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- [BFK2008] Master identification number
5- 6 A2 --- l_srcB [≤ ] Upper 68% confidence level flag on srcB
7- 12 F6.1 ct srcB Net source B-band counts (G1)
14- 17 F4.1 ct e_srcB ? Uncertainty in srcB
19- 24 F6.1 ct srcS1 ? Net source S1-band counts (G1)
26- 29 F4.1 ct e_srcS1 ? Uncertainty in srcS1
31- 36 F6.1 ct srcS2 ? Net source S2-band counts (G1)
38- 41 F4.1 ct e_srcS2 ? Uncertainty in srcS2
43- 48 F6.1 ct srcS ? Net source S-band counts (G1)
50- 53 F4.1 ct e_srcS ? Uncertainty in srcS
55- 60 F6.1 ct srcH ? Net source H-band counts (G1)
62- 65 F4.1 ct e_srcH ? Uncertainty in srcH
67- 72 F6.1 ct srcSc ? Net source Sc-band counts (G1)
74- 77 F4.1 ct e_srcSc ? Uncertainty in srcSc
79- 84 F6.1 ct srcHc ? Net source Hc-band counts (G1)
86- 89 F4.1 ct e_srcHc ? Uncertainty in srcHc
91- 95 F5.2 --- HR ? Hardness ratio (G1)
97-100 F4.2 --- e_HR ? Lower limit uncertainty in HR
102-105 F4.2 --- E_HR ? Upper limit uncertainty in HR
107-111 F5.2 --- C21 ? X-ray color C21 (log(S1/S2) (G1)
113-116 F4.2 --- e_C21 ? Lower limit uncertainty in C21
118-121 F4.2 --- E_C21 ? Upper limit uncertainty in C21
123-127 F5.2 --- C32 ? X-ray color C32 (log(S2/H) (G1)
129-132 F4.2 --- e_C32 ? Lower limit uncertainty in C32
134-137 F4.2 --- E_C32 ? Upper limit uncertainty in C32
139-140 A2 --- l_logLX [≤ ] Upper 68% confidence level flag on
logLX
141-144 F4.1 [10-7W] logLX Log of 0.3-8.0keV luminosity (2)
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Note (2): Assuming D=10.6Mpc.
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Byte-by-byte Description of file: table[6789].dat table10.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- [BFK2008] Master identification number
5- 6 A2 --- l_srcB [≤ ] Upper 68% confidence level flag on srcB
7- 12 F6.1 ct srcB Net source B-band counts (G1)
14- 17 F4.1 ct e_srcB ? Uncertainty in srcB
19- 23 F5.1 ct srcS1 ? Net source S1-band counts (G1)
25- 28 F4.1 ct e_srcS1 ? Uncertainty in srcS1
30- 35 F6.1 ct srcS2 ? Net source S2-band counts (G1)
37- 40 F4.1 ct e_srcS2 ? Uncertainty in srcS2
42- 47 F6.1 ct srcS ? Net source S-band counts (G1)
49- 52 F4.1 ct e_srcS ? Uncertainty in srcS
54- 58 F5.1 ct srcH ? Net source H-band counts (G1)
60- 63 F4.1 ct e_srcH ? Uncertainty in srcH
65- 70 F6.1 ct srcSc ? Net source Sc-band counts (G1)
72- 75 F4.1 ct e_srcSc ? Uncertainty in srcSc
77- 81 F5.1 ct srcHc ? Net source Hc-band counts (G1)
83- 86 F4.1 ct e_srcHc ? Uncertainty in srcHc
88- 92 F5.2 --- HR ? Hardness ratio (G1)
94- 97 F4.2 --- e_HR ? Lower limit uncertainty in HR
99-102 F4.2 --- E_HR ? Upper limit uncertainty in HR
104-108 F5.2 --- C21 ? X-ray color C21 = log(S1/S2) (G1)
110-113 F4.2 --- e_C21 ? Lower limit uncertainty in C21
115-118 F4.2 --- E_C21 ? Upper limit uncertainty in C21
120-124 F5.2 --- C32 ? X-ray color C32 = log(S2/H) (G1)
126-129 F4.2 --- e_C32 ? Lower limit uncertainty in C32
131-134 F4.2 --- E_C32 ? Upper limit uncertainty in C32
136 A1 --- BB Short-term variability from Bayesian block
analysis (2)
138 A1 --- K-S Short-term variability from
Kolmogorov-Smirnov test (2)
140-143 F4.1 --- Sig ? Significance of change in LX (3)
145-146 A2 --- l_logLX [≤] Upper 68% confidence level flag on logLX
147-150 F4.1 [10-7W] logLX Log of 0.3-8.0keV luminosity (4)
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Note (2): short-term variability as follows:
N = non-variable in all observations;
V = variable in at least one observation;
P = possible variability in at least one observation.
Note (3): Between the previous observation and the current observation
respectively (Equ 2).
Note (4): Assuming D=10.6 Mpc.
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Byte-by-byte Description of file: table15.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- [BFK2008] Master identification number
5- 10 F6.1 ct netB ? Net B counts (G1)
12- 15 I4 ct rawB ? Source B-band counts (G1)
17- 20 F4.1 ct bkgB ? Background B-band counts (G1)
22- 25 I4 ct rawS1 ? Source S1-band counts (G1)
27- 30 F4.1 ct bkgS1 ? Background S1-band counts (G1)
32- 35 I4 ct rawS2 ? Source S2-band counts (G1)
37- 40 F4.1 ct bkgS2 ? Background S2-band counts (G1)
42- 45 I4 ct rawH ? Source H-band counts (G1)
47- 50 F4.1 ct bkgH ? Background H-band counts (G1)
52- 55 I4 ct rawBc ? Source Bc-band counts (G1)
57- 60 F4.1 ct bkgBc ? Background Bc-band counts (G1)
62- 65 I4 ct rawSc ? Source Sc-band counts (G1)
67- 70 F4.1 ct bkgSc ? Background Sc-band counts (G1)
72- 75 I4 ct rawHc ? Source Hc-band counts (G1)
77- 80 F4.1 ct bkgHc ? Background Hc-band counts (G1)
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Global notes:
Note (G1): Energy bands, hardness ratios and X-ray colors defined as:
B = broad-band, 0.3-8keV
S = soft-band, 0.3-2.5keV
H = hard-band, 2.5-8keV
S1 = Soft 1 band, 0.3-0.9keV
S2 = Soft 2 band, 0.9-2.5keV
Bc = Conventional broad band, 0.5-8keV
Sc = Conventional soft band, 0.5-2keV
Hc = Conventional hard band, 2-8keV
HR = (Hc-Sc)/(Hc+Sc)
C21 = log(S1/S2)
C32 = log(S2/H)
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 06-Aug-2009