J/MNRAS/452/2858 NIR spectroscopy of Galactic WR stars. III (Kanarek+, 2015)
A near-infrared survey of the inner Galactic plane for Wolf-Rayet stars.
III. New methods: faintest WR stars.
Kanarek G., Shara M., Faherty J., Zurek D., Moffat A.
<Mon. Not. R. Astron. Soc., 452, 2858-2878 (2015)>
=2015MNRAS.452.2858K 2015MNRAS.452.2858K (SIMBAD/NED BibCode)
ADC_Keywords: Stars, Wolf-Rayet ; Photometry, infrared ; Photometry, UBVRI ;
Spectra, infrared ; Equivalent widths ; Spectral types
Keywords: stars: emission-line, Be - stars: Wolf-Rayet -
planetary nebulae: general - Galaxy: stellar content - infrared: stars
Abstract:
A new method of image subtraction is applied to images from a J, K,
and narrow-band imaging survey of 300 deg2 of the plane of the Galaxy,
searching for new Wolf-Rayet (WR) stars. Our survey spans 150° in
Galactic longitude and reaches b=±1° with respect to the
Galactic plane. The survey has a useful limiting magnitude of K=15
over most of the observed Galactic plane, and K=14 (due to severe
crowding) within a few degrees of the Galactic Centre. The new image
subtraction method described here (better than aperture or even
point-spread-function photometry in very crowded fields) detected
several thousand emission-line candidates. In 2011 and 2012 June and
July, we spectroscopically followed up on 333 candidates with
MDM-TIFKAM and Infrared Telescope Facility (IRTF)-SpeX, discovering 89
emission-line sources. These include 49 WR stars, 43 of them
previously unidentified, including the most distant known Galactic WR
stars, more than doubling the number on the far side of the Milky Way.
We also demonstrate our survey's ability to detect very faint
planetary nebulae and other NIR emission objects.
Description:
This survey was previously described in Paper I (Shara et al.,
2009AJ....138..402S 2009AJ....138..402S). More than 88000 exposures were taken of the
Galactic plane on the Cerro Tololo Inter-American Observatory (CTIO)
1.5-m telescope over approximately 200 nights during 2005-2006.
IRTF: at the 3m NASA Infrared Telescope Facility (IRTF), we obtained
NIR spectra of 150 candidate WR stars, selected using the criteria
above, with the SpeX spectrograph.
MDM 2011: during a run of excellent weather over the seven nights in
2011 June, we obtained 113 NIR spectra of candidate stars using TIFKAM
in spectroscopic mode on the 2.4m Hiltner telescope at MDM
Observatory.
MDM 2012: during early 2012, the original survey data were reduced
again, using different methods to produce better images.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 69 49 Spectroscopically confirmed WR stars
table3.dat 69 38 Other NIR emission sources
table4.dat 100 49 Photometry for confirmed WR stars
table5.dat 100 38 Photometry for other NIR emission sources
table6.dat 77 49 Extinction and distances for confirmed WR stars
table7.dat 50 28 *Lines in the NIR WR spectrum
table8.dat 100 26 *Measured equivalent widths for confirmed WN
stars between 2.037 and 2.115um
table9.dat 96 28 *Measured equivalent widths for confirmed WN
stars between 2.148 and 2.217um
table10.dat 100 31 *Measured equivalent widths for confirmed WC
stars between 2.037 and 2.115um
table11.dat 97 23 *Measured equivalent widths for confirmed WC
stars between 2.139 and 2.217um
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Note on table7.dat: a subset of Figer, McLean & Najarro (1997ApJ...486..420F 1997ApJ...486..420F,
table 2). These lines are marked in the spectra shown in Figs 6 and 7.
Note on table8.dat table9.dat table10.dat table11.dat:
Lines were fitted as Gaussian profiles using PAN (http://ifs.wikidot.com/pan)
and then summed to find the equivalent width. Atomic transitions for each line
are given in Table 7.
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See also:
J/AJ/143/149 : NIR spectroscopy of Galactic Wolf-Rayet stars. II (Shara+, 2012)
Byte-by-byte Description of file: table2.dat table3.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Name Name (Field-Object) (G1)
12- 13 I2 h RAh Right ascension (J2000)
15- 16 I2 min RAm Right ascension (J2000)
18- 22 F5.2 s RAs Right ascension (J2000)
24 A1 --- DE- Declination sign (J2000)
25- 26 I2 deg DEd Declination (J2000)
28- 29 I2 arcmin DEm Declination (J2000)
31- 34 F4.1 arcsec DEs Declination (J2000)
36- 42 F7.3 deg GLON [] Galactic longitude
44- 49 F6.3 deg GLAT Galactic latitude
51- 61 A11 --- SpType Wolf-Rayet spectral type (1)
63 A1 --- n_SpType Note on SpType (2)
65- 69 A5 --- Tel Telescope
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Note (1): It is difficult to differentiate between features of WC4-8.
A colon (:) indicates an uncertainty of up to ±2 subtypes.
Note (2): Notes as follows:
a = Originally identified in Gvaramadze, Kniazev & Fabrika (2010, Cat.
J/MNRAS/405/1047) (MN42), and then re-classified as a cLBV transitioning
to late WN in Stringfellow et al. (2012, IAU Symp. 282, 267)
b = Possibly an emitting M-giant
c = Originally identified in Hadfield et al. (2007MNRAS.376..248H 2007MNRAS.376..248H) (HDM 10)
d = Originally identified in Smith et al. (2012AJ....144..166S 2012AJ....144..166S)
(2w06, 2w10, 2w11)
e = Originally classified as a [WC] in Gvaramadze et al. (2010, Cat.
J/MNRAS/405/1047)) (MN102); the brackets indicate a central star of a PN,
which displays WR-like emission
A = These stars are emitting cool stars, M giants or supergiants (Rayner,
Cushing & Vacca, 2004PASP..116..362C 2004PASP..116..362C)
B = Originally identified in Wachter et al. (2011, Bull. Soc. R. Sci. Liege,
80, 291)
C = A number of emission sources seem likely to be YSOs (Greene & Lada,
1996AJ....112.2184G 1996AJ....112.2184G)
D = This object is missing the P Cygni absorption lines normally seen in a
WN7h, and so is likely a high-ionization nebula
1 = Originally identified in Miszalski et al. (2008MNRAS.384..525M 2008MNRAS.384..525M, Cat. V/127)
2 = Originally identified in Acker et al. (1992, Cat. V/84/)
3 = Originally identified in Kerber et al. (2003, Cat. J/A+A/408/1029)
4 = Originally identified in Urquhart et al. (2009, Cat. J/A+A/501/539)
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Byte-by-byte Description of file: table4.dat table5.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- Name Name (Field-Object) (G1
12- 16 F5.2 mag Bmag ?=- NOMAD B magnitude
18- 22 F5.2 mag Vmag ?=- NOMAD V magnitude
24- 28 F5.2 mag Rmag ?=- NOMAD R magnitude
30 A1 --- l_Jmag Limit flag on Jmag
31- 35 F5.2 mag Jmag ?=- 2MASS J magnitude
36 A1 --- u_Jmag [:*+] Uncertainty flag on Jmag (1)
38 A1 --- l_Hmag Limit flag on Hmag
39- 43 F5.2 mag Hmag ?=- 2MASS H magnitude
44 A1 --- u_Hmag [:*+] Uncertainty flag on Hmag (1)
46 A1 --- l_Ksmag Limit flag on Ksmag
47- 51 F5.2 mag Ksmag ?=- 2MASS Ks magnitude
52 A1 --- u_Ksmag [:*+] Uncertainty flag on Ksmag (1)
54 A1 --- l_W1mag Limit flag on W1mag
55- 59 F5.2 mag W1mag ?=- WISE W1 magnitude
60 A1 --- u_W1mag [:*+] Uncertainty flag on W1mag (1)
62- 66 F5.2 mag W2mag ?=- WISE W2 magnitude
67 A1 --- u_W2mag [:*+] Uncertainty flag on W2mag (1)
69 A1 --- l_W3mag Limit flag on W3mag
70- 74 F5.2 mag W3mag ?=- WISE W3 magnitude
75 A1 --- u_W3mag [:*+] Uncertainty flag on W3mag (1)
77 A1 --- l_W4mag Limit flag on W4mag
78- 82 F5.2 mag W4mag ?=- WISE W4 magnitude
83 A1 --- u_W4mag [:*+] Uncertainty flag on W4mag (1)
85- 89 F5.2 mag J-Ks ?=- J-Ks colour index
91- 94 F4.2 mag H-Ks ?=- H-Ks colour index
96-100 F5.2 mag W1-W2 ?=- W1-W2 colour index
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Note (1): Flags as follows:
: = poor photometry quality (C or worse on the PH_QUAL flag)
* = possible contamination
+ = poor PSF fitting
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Byte-by-byte Description of file: table6.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- Name Name (Field-Object) (G1)
12- 22 A11 --- SpType Wolf-Rayet spectral subtype (1)
24- 28 F5.2 mag Jmag ?=- 2MASS J magnitude
30- 34 F5.2 mag Hmag ?=- 2MASS H magnitude
36- 40 F5.2 mag Ksmag ?=- 2MASS Ks magnitude
42- 46 F5.2 mag AKs.J ?=- Ks-band extinction from 2MASS J-Ks colour
48- 51 F4.2 mag AKs.H ?=- Ks-band extinction from 2MASS H-Ks colour
53- 56 F4.2 mag AKs ?=- Ks-band extinction from J-Ks colour
58- 62 F5.2 mag KsMAG ?=- Absolute Ks magnitude (2)
64- 67 F4.1 mag DM ?=- Distance modulus
69- 72 F4.1 kpc Dist ?=- Heliocentric distance (3)
74- 77 F4.1 kpc RG ?=- Galactocentric radius (3)
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Note (1): Subtype values provided in Crowther et al. (2006MNRAS.372.1407C 2006MNRAS.372.1407C).
It is difficult to differentiate between features of WC4-8;
colon (:) indicates an uncertainty of up to ±2 subtypes.
Note (2): derived for spectral subtypes from Rosslowe & Crowther
(2015MNRAS.447.2322R 2015MNRAS.447.2322R).
Note (3): typical uncertainties of ∼25 per cent.
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Byte-by-byte Description of file: table7.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 F5.3 um lambda Wavelength
9- 50 A42 --- Trans Transition
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Byte-by-byte Description of file: table8.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- Name Name (Field-Object) (G1)
13- 20 A8 --- SpType Wolf-Rayet spectral subtype
22- 27 F6.4 --- lcHeII ?=- Line center from the Gaussian fit for
HeII 2.037um line
29- 33 F5.2 0.1nm EWHeII ? Equivalent width for HeII 2.037um line
35- 39 F5.1 km/s FWHMHeII ? FWHM for HeII 2.037um line
41- 46 F6.4 --- lcHeI ?=- Line center from the Gaussian fit for
HeI 2.059um line
48- 53 F6.2 0.1nm EWHeI ? Equivalent width for HeI 2.059um line
55- 59 F5.1 km/s FWHMHeI ? FWHM for HeII 2.037um line
61- 66 F6.4 --- lcHeIIb ?=- Line center from the Gaussian fit for
HeII 2.097um + NV 2.100um + CIII 2.104um +
NIII 2.104um lines
68- 74 F7.2 0.1nm EWHeIIb ? Equivalent width for HeII 2.097um +
NV 2.100um + CIII 2.104um + NIII 2.104um
lines
76- 80 F5.1 km/s FWHMHeIIb ? FWHM for HeII 2.097um + NV 2.100um +
CIII 2.104um + NIII 2.104um lines
82- 87 F6.4 --- lcCIII ?=- Line center from the Gaussian fit for
CIII 2.108um + HeI 2.113um + CIII 2.115um +
NIII 2.115um lines
89- 94 F6.2 0.1nm EWCIII ? Equivalent width for CIII 2.108um or
HeI 2.113um + CIII 2.115um or
NIII 2.115um lines
96-100 F5.1 km/s FWHMCIII ? FWHM for CIII 2.108um + HeI 2.113um +
CIII 2.115um + NIII 2.115um lines
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Byte-by-byte Description of file: table9.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- Name Name (Field-Object) (G1)
13- 20 A8 --- SpType Wolf-Rayet spectral subtype
22- 27 F6.4 --- lcHeII ?=- Line center from the Gaussian fit for
HeII 2.148um line
29- 33 F5.2 0.1nm EWHeII ? Equivalent width for HeII 2.148um line
35- 38 F4.1 km/s FWHMHeII ? FWHM for HeII 2.148um line
40- 45 F6.4 --- lcHeI ?=- Line center from the Gaussian fit for
HeI 2.162um + HeII 2.165um + HI 2.166um
lines
47- 51 F5.2 0.1nm EWHeI ? Equivalent width for HeI 2.162um +
HeII 2.165um + HI 2.166um lines
53- 57 F5.1 km/s FWHMHeI ? FWHM for HeI 2.162um + HeII 2.165um
+ HI 2.166um lines
59- 64 F6.4 --- lcHeIIb ?=- Line center from the Gaussian fit for
HeII 2.189um line
66- 71 F6.2 0.1nm EWHeIIb ? Equivalent width for HeII 2.189um line
73- 77 F5.1 km/s FWHMHeIIb ? FWHM for HeII 2.189um line
79- 84 F6.4 --- lcHeIIc ?=- Line center from the Gaussian fit for
HeII 2.217um line
86- 90 F5.2 0.1nm EWHeIIc ? Equivalent width for HeII 2.217um line
92- 96 F5.1 km/s FWHMHeIIc ? FWHM for HeII 2.217um line
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Byte-by-byte Description of file: table10.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- Name Name (Field-Object) (G1)
11 A1 --- n_Name [abc] Note on Name (G2)
13- 20 A8 --- SpType Wolf-Rayet spectral subtype
22- 27 F6.4 --- lcHeII ?=- Line center from the Gaussian fit for
HeII 2.037um line
29- 33 F5.2 0.1nm EWHeII ? Equivalent width for HeII 2.037um line
35- 39 F5.1 km/s FWHMHeII ? FWHM for HeII 2.037um line
41- 46 F6.4 --- lcHeI ?=- Line center from the Gaussian fit for
HeI 2.059um line
48- 53 F6.2 0.1nm EWHeI ? Equivalent width for HeI 2.059um line
55- 59 F5.1 km/s FWHMHeI ? FWHM for HeII 2.037um line
61- 66 F6.4 --- lcCIV ?=- Line center from the Gaussian fit for
CIV 2.071um + 2.080um + 2.048um lines
68- 74 F7.2 0.1nm EWCIV ? Equivalent width for CIV 2.071um +
2.080um + 2.048um lines
76- 80 F5.1 km/s FWHMCIV ? FWHM for CIV 2.071um + 2.080um +
2.048um lines
82- 87 F6.4 --- lcCIII ?=- Line center from the Gaussian fit for
CIII 2.104um + 2.115um lines
89- 94 F6.2 0.1nm EWCIII ? Equivalent width for CIII 2.104um +
2.115um lines
96-100 F5.1 km/s FWHMCIII ? FWHM for CIII 2.104um + 2.115um lines
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Byte-by-byte Description of file: table11.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- Name Name (Field-Object) (G1)
11 A1 --- n_Name [abc] Note on Name (G2)
13- 18 A6 --- SpType Wolf-Rayet spectral subtype
21- 26 F6.4 --- lcCIV ?=- Line center from the Gaussian fit for
CIV 2.139um line
28- 32 F5.2 0.1nm EWCIV ? Equivalent width for CIV 2.139um line
34- 38 F5.1 km/s FWHMCIV ? FWHM for CIV 2.139um line
40- 45 F6.4 --- lcHeI ?=- Line center from the Gaussian fit for
HeI 2.1.62um + HeII 2.165um lines
47- 52 F6.2 0.1nm EWHeI ? Equivalent width for HeI 1.62um +
HeII 2.165um lines
54- 58 F5.1 km/s FWHMHeI ? FWHM for HeI 1.62um + HeII 2.165um lines
60- 65 F6.4 --- lcHeIIa ?=- Line center from the Gaussian fit for
HeII 2.189um line
67- 72 F6.2 0.1nm EWHeIIa ? Equivalent width for HeII 2.189um line
74- 78 F5.1 km/s FWHMHeIIa ? FWHM for HeII 2.189um line
80- 85 F6.4 --- lcHeIIb ?=- Line center from the Gaussian fit for
HeII 2.217um line
87- 91 F5.2 0.1nm EWHeIIb ? Equivalent width for HeII 2.217um line
93- 97 F5.1 km/s FWHMHeIIb ? FWHM for HeII 2.217um line
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Global notes:
Note (G1): Objects are identified by field number and object number;
this has no relation to RA or Dec.
Note (G2): Notes as follows:
a = This spectrum also contains the CIII line at 2.122um (2.1264 4.18 29.0)
b = This spectrum also contains the HeII line at 2.148um (2.1501 29.00 108.7)
c = This spectrum also contains the HeII line at 2.179um (2.1822 11.86 97.0)
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History:
From electronic version of the journal
References:
Shara et al., Paper I 2009AJ....138..402S 2009AJ....138..402S
Shara et al., Paper II 2012AJ....143..149S 2012AJ....143..149S, Cat. J/AJ/143/149
(End) Patricia Vannier [CDS] 04-Feb-2016