J/ApJS/247/17 Massive stars in APOGEE2 Survey. III. (Roman-Lopes+, 2020)
Massive stars in the SDSS-IV/APOGEE2 Survey.
III. New OB stars in the direction of the Sagittarius spiral arm.
Roman-Lopes A., Roman-Zuniga C.G., Tapia M., Minniti D., Borissova J.
<Astrophys. J. Suppl. Ser., 247, 17 (2020)>
=2020ApJS..247...17R 2020ApJS..247...17R
ADC_Keywords: Stars, OB; Spectral types; Spectra, infrared; Equivalent widths;
Photometry, infrared; Stars, giant
Keywords: Massive stars ; Stellar types ; Near infrared astronomy
Abstract:
We have applied the semi-empirical spectral analysis, developed by the
Sloan Digital Sky Survey (SDSS)-IV/Apache Point Observatory Galactic
Evolution Experiment 2 (APOGEE2) Massive Star Team, to a large sample
of new O- and B-type stars identified along the Sagittarius spiral
arm, in the direction of the southern star clusters NGC3603 and
NGC3576. We obtained H-band spectra for 265 point sources, using the
APOGEE2-S spectrograph at the du Pont Telescope at the Las Campanas
Observatory. We analyzed the associated spectral features deriving
spectral types, as well as the massive star distribution along the
line of sight. From a total of 265 science targets, 95 are classified
as mid- to late-O-type stars (for which only 10 O-type stars are
previously known in the literature), 38 are found to be early- to
mid-B-type stars, and 32 are classified as either yellow or blue
supergiants, completing a total of 165 massive stars.
Description:
The APOGEE (Majewski+ 2017, 2017AJ....154...94M 2017AJ....154...94M) was one of the core
projects of the third phase of the Sloan Digital Sky Survey
(SDSS-III). The extension of the program, the APOGEE2 Survey, expands
its coverage to the southern Milk-Way from the Las Campanas
Observatory (LCO). The APOGEE2-S instrument is a 300-fiber
spectrograph working in the wavelength range of 15000-17000Å in the
near-infrared (NIR) H band, with a mean resolving power of R∼22500.
The APOGEE2-S spectroscopic data of this work were collected during
three nights of the 2018 southern summer (Plate 291-00-C of the CNTAC
Program CN2017B-11).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 114 165 *SDSS-IV/APOGEE2 survey of massive stars in
the Sagittarius Arm
table3.dat 69 165 Line parameters and spectral type estimates
from the APOGEE2-S spectra of O and B stars
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Note on table2.dat: List of O (#1-#95), B (#96-#133), BSG (#134-#149), and
YSG stars (#150-#165) observed in the framework of the CNTAC APOGEE2-S
project CN2017B-11.
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See also:
III/284 : APOGEE-2 data from DR16 (Johnsson+, 2020)
I/347 : Distances to 1.33 billion stars in Gaia DR2 (Bailer-Jones+, 2018)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+, 2003)
J/ApJ/508/397 : H-band Spectral Standards (Meyer+ 1998)
J/ApJS/224/4 : GOSSS III. Additional O-type systems (Maiz Apellaniz+, 2016)
J/A+A/592/A149 : UBVI CCD photom. of Carina region stars (Molina-Lera+, 2016)
J/MNRAS/465/1807 : Deep OB star population in Carina (Mohr-Smith+, 2017)
J/ApJ/855/68 : Massive stars in SDSS-IV/APOGEE SURVEY (Roman-Lopes+, 2018)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq [1/165] Internal identifier
5- 7 A3 --- OT Type of object (1)
9- 26 A18 --- APOGEE APOGEE identifier (2MHHMMSSss+DDMMSSs; J2000)
28- 50 A23 --- OName Literature identifier
52- 57 F6.3 mag Hmag [7.6/13] Apparent 2MASS H band magnitude
59- 73 A15 --- SpType Litterature spectral type and luminosity class;
if any
75-114 A40 --- r_SpType Reference for SpType
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Note (1): Type of object as follows:
O = mid- to late-O-type stars (94 occurrences)
B = early- to mid-B-type stars (38 occurrences)
BSG = blue supergiant stars (16 occurrences)
YSG = yellow supergiant stars (16 occurrences)
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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- 3 I3 --- Seq [1/165] Internal identifier
5- 7 F3.1 0.1nm EWBr11 [0.4/7.4]? Equivalent width of Br11 line (1)
9- 12 F4.1 0.1nm FWHMBr11 [8.0/47]? FWHM of Br11 line (1)
14- 16 F3.1 0.1nm EWBr13 [0.3/9.5]? Equivalent width of Br13 line (1)
18- 21 F4.1 0.1nm FWHMBr13 [10.0/88]? FWHM of Br13 line (1)
23- 25 F3.1 0.1nm EWHeII7-12 [0.1/0.9]? Equivalent width of
HeII 7-12 line (1)
27- 30 F4.1 0.1nm FWHMHeII7-12 [6.5/20]? FWHM of He II 7-12 line (1)
32- 34 F3.1 0.1nm EWHeII7-13 [0.1/0.7]? Equivalent width of
HeII 7-13 line (1)
36- 39 F4.1 0.1nm FWHMHeII7-13 [9/20]? FWHM of He II 7-13 line (1)
41- 47 A7 --- SpT Spectral type from this work
49- 53 A5 --- LCl Luminosity class
55- 69 A15 --- SpType Literature spectral type
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Note (1): In units of Angstroms. Associated uncertainties on the quoted values
are estimated to vary from 10%-25%.
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Acknowledgements:
Alexandre Roman Lopes [aroman at userena.cl] for the data
of object #57 in Table 2.
History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 06-May-2020