J/ApJ/758/15 Chandra X-ray point sources of NGC 300 (Binder+, 2012)
The Chandra Local Volume Survey: the X-ray point-source catalog of NGC 300.
Binder B., Williams B.F., Eracleous M., Gaetz T.J., Plucinsky P.P.,
Skillman E.D., Dalcanton J.J., Anderson S.F., Weisz D.R., Kong A.K.H.
<Astrophys. J., 758, 15 (2012)>
=2012ApJ...758...15B 2012ApJ...758...15B
ADC_Keywords: X-ray sources ; Galaxies, nearby
Keywords: galaxies: individual: NGC 300; galaxies: spiral; X-rays: binaries;
X-rays: galaxies
Abstract:
We present the source catalog of a new Chandra ACIS-I observation of
NGC 300 obtained as part of the Chandra Local Volume Survey. Our 63ks
exposure covers ∼88% of the D25 isophote (R~6.3kpc) and
yields a catalog of 95 X-ray point sources detected at high
significance to a limiting unabsorbed 0.35-8 keV luminosity of
∼1036erg/s. Sources were cross-correlated with a previous XMM-Newton
catalog, and we find 75 "X-ray transient candidate" sources that were
detected by one observatory, but not the other. We derive an X-ray
scale length of 1.7±0.2kpc and a recent star formation rate of
0.12M☉/yr in excellent agreement with optical observations.
Deep, multi-color imaging from the Hubble Space Telescope, covering
∼32% of our Chandra field, was used to search for optical counterparts
to the X-ray sources, and we have developed a new source
classification scheme to determine which sources are likely X-ray
binaries, supernova remnants, and background active galactic nucleus
candidates. Finally, we present the X-ray luminosity functions (XLFs)
at different X-ray energies, and we find the total NGC 300 X-ray
point-source population to be consistent with other late-type galaxies
hosting young stellar populations (≲50Myr). We find that XLF of
sources associated with older stellar populations has a steeper slope
than the XLF of X-ray sources coinciding with young stellar
populations, consistent with theoretical predictions.
Description:
NGC 300 was observed on 2010 September 25 for 63ks using ACIS-I during
the Chandra X-Ray Observatory Cycle 12, observation ID 12238 (see Figure1).
Nine HST fields were used to search for optical counterparts of each
of our X-ray point sources. Three HST Advanced Camera for Surveys
(ACS) observations of NGC 300 were taken as part of the ACS Nearby
Galaxy Survey Treasury (GO-10915). See Figures 2 and 7.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4.dat 66 96 NGC 300 source list
table5.dat 66 96 Logarithmic "probnosource" values for different
energy bands
table6.dat 142 96 Total net counts in different energy bands
table7.dat 50 96 Photon flux in different energy bands
table16.dat 96 69 Optical counterparts to Chandra X-ray sources
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See also:
B/chandra : The Chandra Archive Log (CXC, 1999-2014)
B/hst : HST Archived Exposures Catalog (STScI, 2007)
J/ApJ/746/54 : Chandra X-ray observations of SDSS-DR5 QSOs (Gibson+, 2012)
J/ApJS/193/31 : M33 Chandra ACIS survey: final catalog (Tullmann+, 2011)
J/ApJS/187/495 : SNRs in M33 from optical and X-ray (Long+, 2010)
J/A+A/497/635 : XMM-Newton survey in COSMOS field (Cappelluti+, 2009)
J/A+A/493/339 : XMM-Newton serendipitous Survey. V. (Watson+, 2009)
J/ApJS/174/366 : Chandra ACIS survey of M33 (ChaSeM33) (Plucinsky+, 2008)
J/MNRAS/383/330 : Chandra Small Magellanic Cloud Wing Survey (McGowan+, 2008)
J/ApJ/658/1006 : Radial profiles for 161 face-on spirals (Munoz-Mateos+, 2007)
J/MNRAS/356/568 : Deep Chandra survey of the Groth Strip (Nandra+, 2005)
J/A+A/443/103 : X-ray properties of NGC 300. I. (Carpano+, 2005)
J/ApJ/602/231 : Chandra point sources in nearby galaxies (Colbert+, 2004)
J/ApJ/577/738 : M31 Chandra X-ray point sources (Kong+, 2002)
J/ApJ/554/742 : Chandra Deep Survey of the HDF-N (Hornschemeier+, 2001)
Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Seq [1/95] Running sequence number
4- 21 A18 --- ID Source identifier (HHMMSS.ss+DDMMSS.s; J2000)
23- 31 F9.6 deg RAdeg [13.5/13.9] Right Ascension (J2000)
33- 42 F10.6 deg DEdeg [-37.9/-37.4] Declination (J2000)
44- 47 F4.2 arcsec ePos [0.03/1.9] Positional error (1)
49- 55 E7.3 s.cm2 Texp Sum of mean exposure map value in source region
57- 61 F5.2 pix Rsrc Average radius of source extraction region (2)
63- 66 F4.1 --- theta Off-axis angle
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Note (1): A simple error circle around R.A. and Dec.
Note (2): 1 sky pixel = 0.392".
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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- 2 I2 --- Seq [1/95] Source number
4 A1 --- l_logP1 Limit flag on logP1
5- 10 F6.2 [-] logP1 Log Poisson probability 0.5-8 keV band is not a
source (3)
12 A1 --- l_logP2 Limit flag on logP2
13- 18 F6.2 [-] logP2 Log Poisson probability 0.5-2 keV band is not a
source (3)
20 A1 --- l_logP3 Limit flag on logP3
21- 26 F6.2 [-] logP3 Log Poisson probability 2-8 keV band is not a
source (3)
28 A1 --- l_logP4 Limit flag on logP4
29- 34 F6.2 [-] logP4 Log Poisson probability 0.35-8 keV band is not a
source (3)
36 A1 --- l_logP5 Limit flag on logP5
37- 42 F6.2 [-] logP5 Log Poisson probability 0.35-1.1 keV band is not
a source (3)
44 A1 --- l_logP6 Limit flag on logP6
45- 50 F6.2 [-] logP6 Log Poisson probability 1.1-2.6 keV band is not a
source (3)
52 A1 --- l_logP7 Limit flag on logP7
53- 58 F6.2 [-] logP7 Log Poisson probability 2.6-8 keV band is not a
source (3)
60 A1 --- l_logP8 Limit flag on logP8
61- 66 F6.2 [-] logP8 Log Poisson probability 0.35-2 keV band is not a
source (3)
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Note (3): Values smaller than -10 have been replaced by "←10.".
To be included in the final NGC 300 catalog, a source was required
to have a probnosource (pns) value less than 4x10-6 in any of the
nine energy bands; if only the 0.35-8keV band were considered, ∼4% of
significant sources would have been lost. See section 2.3.
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Seq [1/95] Source number
4 A1 --- l_logNC1 Limit flag on logNC1
5- 10 F6.1 [ct] logNC1 [3.3/1933] log of 0.5-8 keV band net counts
12- 15 F4.1 [ct] E_logNC1 ? Upper limit uncertainty in logNC1
17- 20 F4.1 [ct] e_logNC1 ? Lower limit uncertainty in logNC1
22 A1 --- l_logNC2 Limit flag on logNC2
23- 28 F6.1 [ct] logNC2 [0.9/1549] log of 0.5-2 keV band net counts
30- 33 F4.1 [ct] E_logNC2 ? Upper limit uncertainty in logNC2
35- 38 F4.1 [ct] e_logNC2 ? Lower limit uncertainty in logNC2
40 A1 --- l_logNC3 Limit flag on logNC3
41- 45 F5.1 [ct] logNC3 [0.9/385] log of 2-8 keV band net counts
47- 50 F4.1 [ct] E_logNC3 ? Upper limit uncertainty in logNC3
52- 55 F4.1 [ct] e_logNC3 ? Lower limit uncertainty in logNC3
57 A1 --- l_logNC4 Limit flag on logNC4
58- 63 F6.1 [ct] logNC4 [3.3/1963] log of 0.35-8 keV band net counts
65- 68 F4.1 [ct] E_logNC4 ? Upper limit uncertainty in logNC4
70- 73 F4.1 [ct] e_logNC4 ? Lower limit uncertainty in logNC4
75 A1 --- l_logNC5 Limit flag on logNC5
76- 80 F5.1 [ct] logNC5 [0.7/740] log of 0.35-1.1 keV band net counts
82- 85 F4.1 [ct] E_logNC5 ? Upper limit uncertainty in logNC5
87- 90 F4.1 [ct] e_logNC5 ? Lower limit uncertainty in logNC5
92 A1 --- l_logNC6 Limit flag on logNC6
93- 97 F5.1 [ct] logNC6 [0.7/972] log of 1.1-2.6 keV band net counts
99-102 F4.1 [ct] E_logNC6 ? Upper limit uncertainty in logNC6
104-107 F4.1 [ct] e_logNC6 ? Lower limit uncertainty in logNC6
109 A1 --- l_logNC7 Limit flag on logNC7
110-114 F5.1 [ct] logNC7 [1/252] log of 2.6-8 keV band net counts
116-119 F4.1 [ct] E_logNC7 ? Upper limit uncertainty in logNC7
121-124 F4.1 [ct] e_logNC7 ? Lower limit uncertainty in logNC7
126 A1 --- l_logNC8 Limit flag on logNC8
127-132 F6.1 [ct] logNC8 [0.9/1579] log of 0.35-2 keV band net counts
134-137 F4.1 [ct] E_logNC8 ? Upper limit uncertainty in logNC8
139-142 F4.1 [ct] e_logNC8 ? Lower limit uncertainty in logNC8
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Byte-by-byte Description of file: table7.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- Seq [1/95] Source number
4- 8 F5.2 [ct/cm2/s] logF1 ? log of 0.5-8 keV band photon flux
10- 14 F5.2 [ct/cm2/s] logF2 ? log of 0.5-2 keV band photon flux
16- 20 F5.2 [ct/cm2/s] logF3 ? log of 2-8 keV band photon flux
22- 26 F5.2 [ct/cm2/s] logF4 ? log of 0.35-8 keV band photon flux
28- 32 F5.2 [ct/cm2/s] logF5 ? log of 0.35-1.1 keV band photon flux
34- 38 F5.2 [ct/cm2/s] logF6 ? log of 1.1-2.6 keV band photon flux
40- 44 F5.2 [ct/cm2/s] logF7 ? log of 2.6-8 keV band photon flux
46- 50 F5.2 [ct/cm2/s] logF8 ? log of 0.35-2 keV band photon flux
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Byte-by-byte Description of file: table16.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Seq [1/95] X-ray source number
3 A1 --- m_Seq Multiple optical counterpart candidate
indication for Seq
5- 6 A2 --- Src Type of source: G=Galaxy; PS=point source
(see section 4.3.1 for this X-ray source)
8- 11 F4.2 arcsec Sep [0/1.5]? The positional offset from the
Chandra X-ray source location
13 A1 --- f_Sep [c] c: no optical counterpart detected
15- 19 F5.2 mag F435W ? HST F435W magnitude
21- 24 F4.2 mag e_F435W ? F435W uncertainty
26- 30 F5.2 mag F475W ? HST F475W magnitude
32- 35 F4.2 mag e_F475W ? F475W uncertainty
37- 41 F5.2 mag F555W ? HST F555W magnitude
43- 46 F4.2 mag e_F555W ? F555W uncertainty
48- 52 F5.2 mag F606W ? HST F606W magnitude
54- 57 F4.2 mag e_F606W ? F606W uncertainty
59- 63 F5.2 mag F814W ? HST F814W magnitude
65- 68 F4.2 mag e_F814W ? F814W magnitude
70- 74 F5.2 mag F814W2 ? Second value of F814W magnitude
76- 79 F4.2 mag e_F814W2 ? F814W2 uncertainty
81- 84 F4.1 aW/m2 FX 2-10keV X-ray flux (1)
86- 90 F5.2 [-] [X/V] ? log of X-ray to optical flux ratio (2)
92- 96 F5.2 [-] [X/V]2 ? Second value of log(Fx/Fv) (2)
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Note (1): X-ray flux is unabsorbed in the 0.35-8keV energy band.
Note (2): FV is calculated from either the F555W or F606W magnitude,
depending on which is available for a given observation. Only the first
five X-ray sources with optical counterpart candidates are listed.
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Acknowledgement:
Breanna Binder for the complete table16
History:
From electronic version of the journal
References:
Binder et al. Paper II: NGC 404. 2013ApJ...763..128B 2013ApJ...763..128B Cat. J/ApJ/763/128
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 30-Jun-2014