J/AJ/153/115 VLT/SINFONI observations of MIPSGAL "bubbles" (Silva+, 2017)
VLT/SINFONI observations of Spitzer/MIPSGAL 24 µm circumstellar shells:
revealing the natures of their central sources.
Silva K.M., Flagey N., Noriega-Crespo A., Carey S., Ingallinera A.
<Astron. J., 153, 115-115 (2017)>
=2017AJ....153..115S 2017AJ....153..115S (SIMBAD/NED BibCode)
ADC_Keywords: Galactic plane ; Stars, late-type ; Stars, early-type ;
Stars, giant ; Stars, supergiant ; Photometry, infrared ;
Spectral types ; Stars, distances ; Extinction ; Stars, diameters
Keywords: stars: early-type - stars: emission-line, Be - stars: late-type -
stars: Wolf - Rayet
Abstract:
We present Very Large Telescope/Spectrograph for INtegral Field
Observations in the Near Infrared H- and K-band spectra of potential
central stars within the inner 8"-by-8" regions of 55 MIPSGAL "bubbles"
(MBs), sub-arcminute circumstellar shells discovered in the mid-IR
survey of the Galactic plane with Spitzer/MIPS. At magnitudes brighter
than 15, we detect a total of 230 stars in the K band and 179 stars in
the H band. We spectrally identify 145 stars in all but three MBs,
with average magnitudes of 13.8 and 12.7 respectively, using spectral
libraries and previous studies of near-IR stellar spectra. We also use
tabulated intrinsic stellar magnitudes and colors to derive distances
and extinction values, and to better constrain the classifications of
the stars. We reliably identify the central sources for 21 of the 55
MBs, which we classify as follows: one Wolf-Rayet, three luminous blue
variable candidates, four early-type (O to F), and 15 late-type (G to M)
stars. The 21 central sources are, on average, one magnitude fainter
than these in the most recent study of MBs, and we notice a significant
drop in the fraction of massive star candidates. For the 34 remaining
MBs in our sample, we are unable to identify the central sources due
to confusion, low spectroscopic signal-to-noise ratio, and/or lack of
detections in the images near the centers of the bubbles. We discuss
how our findings compare with previous studies and support the trend,
for the most part, between the shells' morphologies in the mid-IR and
central sources spectral types.
Description:
Data were acquired in service mode during UT 2014 May 23-June 7
using VLT/SINFONI observations. We used two of SINFONI's four gratings
providing spectral resolutions R=3000 and 4000 in the H and K bands,
respectively, with the field of view of 8" by 8" (without adaptive optics).
The targets are 55 MIPSGAL "bubbles" (MBs) that have not been
previously classified as PNe, whose central sources were unidentified
at the time of the Period 93 Call for Proposals (UT 2013 October 01),
and appeared to contain at least one potential central source detected
in the near-IR images of the Two Micron All-Sky Survey (2MASS,
Skrutskie et al. 2006, Cat. VII/233) or the UKIRT Infrared Deep Sky
Survey (UKIDSS, Warren et al. 2007MNRAS.381.1400W 2007MNRAS.381.1400W).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 66 55 Summary of the VLT/SINFONI Observations
table2.dat 116 125 Late-type Star Results
table3.dat 76 16 Early-type Star Results, Assuming Giants
table4.dat 81 16 Early-type Star Results, Assuming Supergiants
table6.dat 146 55 Central Objects of MIPSGAL Bubbles
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See also:
VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)
J/ApJ/508/397 : H-band Spectral Standards (Meyer+ 1998)
J/ApJ/670/428 : Bubbles in the galactic disk. II. (Churchwell+, 2007)
J/ApJ/671/781 : Red supergiants in Sct-Cru Galactic arm (Davies+, 2007)
J/AJ/139/1542 : A catalog of MIPSGAL disk and ring sources (Mizuno+, 2010)
J/AJ/149/64 : MIPSGAL 24µm point source catalog (Gutermuth+, 2015)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 6 A6 --- ID Target identifier (MBNNNN)
8- 26 A19 --- IAU Official IAU name (MGE GLLL.llll+BB.bbbb in Simbad)
28- 35 F8.4 deg RAdeg Right Ascension in decimal degrees (J2000)
37- 44 F8.4 deg DEdeg Declination in decimal degrees (J2000)
46- 47 I2 --- NExpH [4/20] Number of exposure in H band
49- 50 I2 s ExpH [7/60] H band exposure time
52- 53 I2 --- NExpK [4/24] Number of exposure in K band
55- 56 I2 s ExpK [7/60] K band exposure time
58- 61 F4.1 mag Hmag [9.5/16.5]? Depth of the H band exposure (1)
63- 66 F4.1 mag Kmag [8.6/15]? Depth of the K band exposure (1)
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Note (1): The faintest magnitudes of a star that we identified. A blank
indicates that no star was identified.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- ID Object identifier (mbNNNN-NN)
11- 18 F8.4 deg RAdeg Right ascension in decimal degrees (J2000) (1)
20- 27 F8.4 deg DEdeg Declination in decimal degrees (J2000) (1)
29- 32 F4.1 0.1nm EWCOa [-0.7/31.8] CO feature at 2.27µm equivalent
width (Å) (2)
34- 37 F4.1 0.1nm EWCOb [10/61.6] CO feature at 2.27µm equivalent
width (Å) (3)
39- 43 A5 --- SGTypea Supergiant spectral type (2)
45- 49 F5.1 pc SGDista [15.9/396.6]? Supergiant distance (2)
51- 54 F4.1 mag SGAva [-5.9/13.2]? Supergiant visual extinction (2)
56- 60 A5 --- SGTypeb Supergiant spectral type (3)
62- 66 F5.1 pc SGDistb [27.4/466.3]? Supergiant distance (3)
68- 71 F4.1 mag SGAvb [-6.1/13.2]? Supergiant visual extinction (3)
73- 77 A5 --- GTypea Giant spectral type (2)
79 A1 --- f_GTypea [b] Flag on GTypea (4)
81- 84 F4.1 pc GDista [2.6/95.9]? Giant distance (2)
86 A1 --- f_GDista [b] Flag on GDista (4)
88- 91 F4.1 mag GAva [-6.7/13.1]? Giant visual extinction (2)
93 A1 --- f_GAva [b] Flag on GAva (4)
95- 99 A5 --- GTypeb Giant spectral type (3)
101 A1 --- f_GTypeb [b] Flag on GTypeb (4)
103-107 F5.1 pc GDistb [3.7/178.1]? Giant distance (3)
109 A1 --- f_GDistb [b] Flag on GDistb (4)
111-114 F4.1 mag GAvb [-0.3/13.2]? Giant visual extinction (3)
116 A1 --- f_GAvb [b] Flag on GAvb (4)
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Note (1): Astrometry suffered from an offset due to the inaccuracy of the
VLT's pointing: right ascension on average by 0.00016 with a
standard deviation of 0.00007; declination, on average, by -0.00049
with a standard deviation of 0.00012.
Note (2): Values derived using the method from Davies et al. (2007,
J/ApJ/671/781). Blanks indicate either that the equivalent width
measured falls outside the range the method could derive a
classification for or the distance or extinction value could not be
computed.
Note (3): Values derived using the method from Figer et al.
(2006ApJ...643.1166F 2006ApJ...643.1166F). Blanks indicate either that the equivalent
width measured falls outside the range the method could derive a
classification for or the distance or extinction value could not be
computed.
Note (4): Flag as follows:
b = Our suggested classification, distance and visual extinction derived for
that type.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- ID Object identifier (mbNNNN-NN)
11- 18 A8 --- SpType Spectral type derived from comparison with
Meyer et al. (1998, J/ApJ/508/397)
20- 24 F5.1 kpc O5IIIDist [8.7/122.9] Distance with spectral type O5III
(1)
25 A1 --- f_O5IIIDist [b] Flag on O5IIIDist (G1)
27- 30 F4.1 mag O5IIIAv [-0.3/11.9] Visual extinction with spectral
type O5III (1)
31 A1 --- f_O5IIIAv [b] Flag on O5IIIAv (G1)
33- 36 F4.1 kpc B1IIIDist [2.4/34.6] Distance with spectral type B1III
(1)
37 A1 --- f_B1IIIDist [b] Flag on B1IIIDist (G1)
39- 42 F4.1 mag B1IIIAv [0.8/13.1] Visual extinction with spectral
type B1III (1)
43 A1 --- f_B1IIIAv [b] Flag on B1IIIAv (G1)
45- 47 F3.1 kpc A0IIIDist [0.5/7.7] Distance with spectral type A0III
(1)
48 A1 --- f_A0IIIDist [b] Flag on A0IIIDist (G1)
50- 53 F4.1 mag A0IIIAv [0.4/12.6] Visual extinction with spectral
type A0III (1)
54 A1 --- f_A0IIIAv [b] Flag on A0IIIAv (G1)
56- 58 F3.1 kpc F0IIIDist [0.4/6.3] Distance with spectral type F0III
(1)
59 A1 --- f_F0IIIDist [b] Flag on F0IIIDist (G1)
61- 64 F4.1 mag F0IIIAv [0.3/12.5] Visual extinction with spectral
type F0III (1)
65 A1 --- f_F0IIIAv [b] Flag on F0IIIAv (G1)
67- 69 F3.1 kpc G0IIIDist [0.4/6.4] Distance with spectral type G0III
(1)
70 A1 --- f_G0IIIDist [b] Flag on G0IIIDist (1)
72- 75 F4.1 mag G0IIIAv [0.1/12.4] Visual extinction with spectral
type G0III (1)
76 A1 --- f_G0IIIAv [b] Flag on G0IIIAv (1)
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Note (1): Distances and visual extinctions derived from the measured magnitudes
and giants' intrinsic colors in the H and K bands.
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- ID Object identifier (mbNNNN-NN)
11- 18 A8 --- SpType Spectral type derived from comparison with
Meyer et al. (1998, J/ApJ/508/397)
20- 24 F5.1 kpc O5IDist [10.8/153.3] Distance with spectral type O5I (1)
25 A1 --- f_O5IDist [b] Flag on O5IDist (G1)
27- 30 F4.1 mag O5IAv [-0.3/11.9] Visual extinction with spectral
type O5I (1)
31 A1 --- f_O5IAv [b] Flag on O5IAv (G1)
33- 37 F5.1 kpc B1IDist [8.3/117.8] Distance with spectral type B1I (1)
38 A1 --- f_B1IDist [b] Flag on B1IDist (G1)
40- 43 F4.1 mag B1IAv [0.7/12.9] Visual extinction with spectral type
B1I (1)
44 A1 --- f_B1IAv [b] Flag on B1IAv (G1)
46- 50 F5.1 kpc A0IDist [11.4/161.2] Distance with spectral type A0I (1)
51 A1 --- f_A0IDist [b] Flag on A0IDist (G1)
53- 56 F4.1 mag A0IAv [0.4/12.7] Visual extinction with spectral type
A0I (1)
57 A1 --- f_A0IAv [b] Flag on A0IAv (G1)
59- 63 F5.1 kpc F0IDist [15.2/215.5] Distance with spectral type F0I (1)
64 A1 --- f_F0IDist [b] Flag on F0IDist (G1)
66- 69 F4.1 mag F0IAv [0.1/12.4] Visual extinction with spectral type
F0I (1)
70 A1 --- f_F0IAv [b] Flag on F0IAv (G1)
72- 76 F5.1 kpc G0IDist [22.2/314.9] Distance with spectral type G0I (1)
78- 81 F4.1 mag G0IAv [-0.3/12] Visual extinction with spectral type
G0I (1)
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Note (1): Distances and visual extinctions derived from the measured magnitudes
and supergiants' intrinsic colors in the H and K bands.
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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 A1 --- Cat [ABCDE] MIPSGAL "bubble" (MB) category (1)
3- 8 A6 --- ID Target identifier (MBNNNN)
10- 11 I2 --- Star1 [1/6]? First star number
13- 14 I2 --- Star2 [3/7]? Second star number
16- 17 I2 --- Star3 [8]? Third star number
19- 27 A9 --- SpType1 First spectral type
29- 38 A10 --- SpType2 Second spectral type
40- 43 F4.1 kpc Dist1 [2.6/31.8]? First distance
44 A1 --- f_Dist1 [a] Flag on Dist1 (2)
46- 49 F4.1 kpc Dist2 [4.4/18.4]? Second distance
50 A1 --- f_Dist2 [a] Flag on Dist2 (2)
52- 53 I2 arcsec Rad [11/44] Radius in arcseconds
55- 58 F4.2 pc Rad1 [0.24/3.85]? First radius in parsecs
60- 63 F4.2 pc Rad2 [0.43/1.7]? Second radius in parsecs
65-146 A82 --- Com Comment
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Note (1): Category as follows:
A = Very likely - MB at the center of which we identify single clear
candidates;
B = Possible - We find stars that lie within close proximity (∼1"), but not
exactly at the center of the MB;
C = Confusion - This MB has multiple stars near its center;
D = Spectral type unknown - We detect at least one star near the centers of
14 MBs in either VLT/SINFONI or UKIDSS data but are unable to identify
their spectral types;
E = No star detected near the center - Contains the remaining eight MBs that
showed no stars within 1" of their centers in both the UKIDSS images and
our VLT/SINFONI observations.
Note (2): Flag as follows:
a = Extinction-to-distance ratio significantly out of the expected range.
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Global notes:
Note (G1): Flag as follows:
b = The most plausible value.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Tiphaine Pouvreau [CDS] 27-Apr-2018