J/ApJ/827/46 A deep Chandra ACIS survey of M51 (Kuntz+, 2016)
A deep Chandra ACIS survey of M51.
Kuntz K.D., Long K.S., Kilgard R.E.
<Astrophys. J., 827, 46-46 (2016)>
=2016ApJ...827...46K 2016ApJ...827...46K (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, nearby ; X-ray sources ; Cross identifications
Keywords: galaxies: individual: M51; galaxies: ISM; ISM: supernova remnants;
X-rays: binaries ; X-rays: general
Abstract:
We have obtained a deep X-ray image of the nearby galaxy M51 using
Chandra. Here we present the catalog of X-ray sources detected in
these observations and provide an overview of the properties of the
point-source population. We find 298 sources within the D25 radii of
NGC 5194/5, of which 20% are variable, a dozen are classical
transients, and another half dozen are transient-like sources. The
typical number of active ultraluminous X-ray sources in any given
observation is ∼5, and only two of those sources persist in an
ultraluminous state over the 12yr of observations. Given reasonable
assumptions about the supernova remnant population, the luminosity
function is well described by a power law with an index between 1.55
and 1.7, only slightly shallower than that found for populations
dominated by high-mass X-ray binaries (HMXBs), which suggests that the
binary population in NGC 5194 is also dominated by HMXBs. The
luminosity function of NGC 5195 is more consistent with a low-mass
X-ray binary dominated population.
Description:
This deep study of M51 is composed of 107ks of archival Chandra
observations, to which we have added another 745ks of observations.
All of the observations were made with the ACIS-S array.
M51 has been observed extensively with HST. In particular, essentially
all of M51 and its companion NGC 5195 was imaged with Advanced Camera
for Surveys (ACS) in V, R, and I (F435W, F555W, F814W) and Hα
(F658N) as a Hubble Legacy Project (Proposal ID 10452, PI: S. Beckwith).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 49 12 Chandra observations
table4.dat 74 503 M51 X-ray point sources
table5.dat 100 503 M51 X-ray point source fluxes & luminosities
table6.dat 155 438 M51 X-ray point source identifications
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See also:
B/chandra : The Chandra Archive Log (CXC, 1999-2014)
J/ApJ/764/41 : X-ray binary evolution across cosmic time (Fragos+, 2013)
J/MNRAS/419/2095 : HMXBs in nearby galaxies (Mineo+, 2012)
J/ApJS/192/10 : Chandra ACIS survey in 383 nearby galaxies. I. (Liu, 2011)
J/AJ/136/2782 : Star formation efficiency in nearby galaxies (Leroy+, 2008)
J/AJ/136/2563 : HI Nearby Galaxy Survey, THINGS (Walter+, 2008)
J/AJ/135/1567 : Bright star clusters in M51 (Hwang+, 2008)
J/AJ/133/2559 : Compact radio sources in spiral galaxies. II. (Maddox+, 2007)
J/ApJ/664/458 : Spectral fit of ULX sources (Devi+, 2007)
J/ApJS/157/59 : Ultraluminous X-ray sources in nearby galaxies (Liu+, 2005)
J/ApJ/602/231 : Chandra X-ray point sources in nearby galaxies (Colbert+, 2004)
J/ApJ/601/735 : M51 luminous X-ray sources (Terashima+, 2004)
J/ApJ/577/31 : PNe in six galaxies (Ciardullo+, 2002)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 5 I5 --- ObsID Chandra observation ID
7- 17 A11 "Y/M/D" obs.date UT date of the observation
18 A1 --- --- [T]
19- 26 A8 "h:m:s" obs.time UT time of the observation
28 A1 --- Epoch Major epoch
30- 35 F6.2 ks Exp [9.6/190] Exposure time
37- 42 F6.2 deg Roll Roll angle
44- 49 A6 --- Mode Mode
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- ID Object identifier (XNNN)
6- 7 I2 h RAh [13] Hour of Right Ascension (J2000)
9- 10 I2 min RAm [28/31] Minute of Right Ascension (J2000)
12- 16 F5.2 s RAs Second of Right Ascension (J2000)
18 A1 --- DE- [+] Sign of Declination (J2000)
19- 20 I2 deg DEd [46/47] Degree of Declination (J2000)
22- 23 I2 arcmin DEm Arcminute of Declination (J2000)
25- 28 F4.1 arcsec DEs Arcsecond of Declination (J2000)
30- 33 F4.2 arcsec PosErr [0/1.5] 1σ statistical position error
35- 39 F5.1 ks Exp [10/855] Exposure time
41- 46 F6.3 10-3ct/s Rate [-0.25/41.4] The 0.35-8.0keV band count rate
48- 52 F5.3 10-3ct/s e_Rate [0.006/0.8] Uncertainty in Rate
54- 58 F5.2 --- HR1 [-3.6/1.6] Hardness ratio, (M-S)/T (1)
60- 63 F4.2 --- e_HR1 [0.01/3] Uncertainty in HR1
65- 69 F5.2 --- HR2 [-2/1] Hardness ratio, (H-M)/T (2)
71- 74 F4.2 --- e_HR2 [0/5] Uncertainty in HR2
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Note (1): Calculated from photon fluxes for the 0.35-1.1keV (S), 1.1-2.6keV (M),
and 0.35-8.0keV (T) band.
Note (2): Calculated from photon fluxes for the 1.1-2.6keV (M), 2.6-8keV (H),
and 0.35-8.0keV (T) bands.
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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- 4 A4 --- ID Object identifier (XNNN)
6- 12 F7.3 10-6ct/cm2/s F1 [-1.6/216] Chandra 0.35-8keV band flux (3)
14- 18 F5.3 10-6ct/cm2/s e_F1 [0.02/8] Uncertainty in F1 (3)
20- 26 F7.3 10-6ct/cm2/s F2 [-3.2/136] Chandra 0.35-1.1keV band flux (3)
28- 32 F5.3 10-6ct/cm2/s e_F2 [0.003/6] Uncertainty in F2 (3)
34- 39 F6.3 10-6ct/cm2/s F3 [-0.003/50] Chandra 1.1-2.6keV band flux (3)
41- 45 F5.3 10-6ct/cm2/s e_F3 [0.001/2.2] Uncertainty in F3 (3)
47- 52 F6.3 10-6ct/cm2/s F4 [-0.83/33.4] Chandra 2.6-8keV band flux (3)
54- 58 F5.3 10-6ct/cm2/s e_F4 [0.002/3.5] Uncertainty in F4 (3)
60- 66 F7.3 10-6ct/cm2/s F5 [-0.5/121] Chandra 0.5-2keV band flux (3)
68- 72 F5.3 10-6ct/cm2/s e_F5 [0.008/3.4] Uncertainty in F5 (3)
74- 79 F6.3 10-6ct/cm2/s F6 [-0.03/44.1] Chandra 2-8keV band flux (3)
81- 85 F5.3 10-6ct/cm2/s e_F6 [0.002/4.2] Uncertainty in F6 (3)
87- 93 F7.2 10+29W LX [-22.7/3149.5] The 0.35-8keV band
luminosity (4)
95-100 F6.2 10+29W e_LX [0.3/113] Uncertainty in LX (4)
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Note (3): In units of 1e-6 photons/cm2/s.
Note (4): In units of 1e36erg/s. The errors are purely statistical.
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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- 4 A4 --- ID Object identifier (XNNN)
6- 7 I2 --- T04 ? Terashima+ 2004, J/ApJ/601/735 identifier
8- 9 A2 --- f_T04 Flag on T04 (1)
11- 31 A21 --- K05 Kilgard+ 2005ApJS..159..214K 2005ApJS..159..214K identifier
33- 36 A4 --- --- [M07-]
37- 39 I3 --- [MCK2007] ? Maddox+ 2007, J/AJ/133/2559 identifier
41- 87 A47 --- Multi Multiwavelength identifier (SDSS objID or
FIRST)
89- 97 A9 --- Type Object type (2)
99-100 A2 --- Gal Galaxy against which source is projected
(A = NGC 5194; B = NGC 5195)
102-111 A10 --- LT Long-term variation (3)
113-122 A10 --- MT Medium-term variation (4)
124-155 A32 --- Notes Additional notes (5)
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Note (1): -a for NGC 5194; <[TW2004] NGC 5194 NN> in Simbad;
-b for NGC 5195; <[TW2004] NGC 5195 NN> in Simbad;
-o for other; <[TW2004] Source NN> in Simbad.
Note (2): Types taken from SDSS are inside parenthesis.
FGS = foreground star;
GAL = galaxy;
HAB = Hα bubble;
S = stellar (point like, but not necessarily a star);
SFR = star-forming region;
SN = historical supernova.
STR = foreground star.
Note (3): Defined as variation between epochs. The letters indicate the bands in
which variation was detected. Note that sources in the outer regions
of the field may not have measured long-term variation due to lack of
multi-epoch coverage.
S: 0.35-1.1keV, M: 1.1-2.6keV, H 2.6-8.0keV, T:0.35-8.0keV,
s: 0.5-2.0keV, h: 2.0-8.0keV.
Note (4): Defined as variation between observations in epoch E. The letters
indicate the bands in which variation was detected.
S: 0.35-1.1keV, M: 1.1-2.6keV, H 2.6-8.0keV, T:0.35-8.0keV,
s: 0.5-2.0keV, h: 2.0-8.0keV.
Note (5): When the source is marked as type FGS, the notes contain information
about the proper motion. When the source is marked as type HAB, the
notes contain information about the Hα morphology. Objects
previously noted as ULX are noted here, even if they are not
persistent. Transient and "drop-out" sources are noted.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 17-Nov-2016