J/ApJ/672/398 JHK' photometry of M17 silhouette object (Ito+, 2008)
Near-infrared silhouette object survey in M17.
Ito M., Yamashita T., Sako S., Takami H., Hayano Y., Terada H.
<Astrophys. J., 672, 398-409 (2008)>
=2008ApJ...672..398I 2008ApJ...672..398I
ADC_Keywords: Clusters, open ; YSOs ; Stars, pre-main sequence ;
Photometry, infrared
Keywords: infrared: ISM - ISM: individual (M17) - ISM: lines and bands -
stars: formation - stars: pre-main sequence
Abstract:
To study how the structure of the envelopes of young stellar objects
(YSOs) evolve, we carried out a deep JHK'-band imaging survey of the
M17 star-forming region using a near-infrared camera and the Infrared
Camera and Spectrograph with adaptive optics mounted on the Subaru
Telescope. In this survey, we found 51 dark silhouettes against bright
near-infrared nebula emissions as background lights. They are regarded
as envelopes associated with YSOs due to their size and association
with the YSOs. We derived size, morphology, extinction, and mass for
each silhouette envelope.
Description:
Imaging observations of the M17 star-forming region were carried out in
the J, H, and K' bands on 2003 August 16, 2004 July 5, and 2004 August
7 using the Infrared Camera and Spectrograph (IRCS) with AO on the
8.2m Subaru Telescope on Mauna Kea.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 106 51 Photometry and derived parameters of silhouette
and YSOs
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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 A3 --- [IYS2008] Designation (JNN, HNN, KNN or NSN) (1)
5- 6 I2 h RAh Right ascension (J2000)
8- 9 I2 min RAm Right ascension (J2000)
11- 16 F6.3 s RAs Right ascension (J2000)
18 A1 --- DE- Declination sign (J2000)
19- 20 I2 deg DEd Declination (J2000)
22- 23 I2 arcmin DEm Declination (J2000)
25- 29 F5.2 arcsec DEs Declination (J2000)
31- 36 F6.3 mag Jmag ?=- J magnitude (1.25±0.16um)
38- 43 F6.3 mag Hmag ?=- H magnitude (1.63±0.30um)
45- 50 F6.3 mag K'mag ?=- K' magnitude (2.12±0.35um)
52 A1 --- l_E(IR) [<] Limit flag on E(IR) (for the HK' objects)
53- 57 F5.3 mag E(IR) ?=- Amount of the IR excess
59- 61 F3.1 solMass Mass ?=- Mass of the central YSO
63- 67 F5.3 mag AV ?=- Silhouette peak extinction
69- 79 A11 --- Morph Morphology of the silhouette (2)
81- 84 F4.2 arcsec Rad1 Distance from the extinction peak to the
silhouette border
86- 89 F4.2 arcsec Rad2 ?=- Distance from the YSO in the silhouette
to the silhouette border
90 A1 --- --- [-]
91- 94 F4.2 arcsec Rad2u ? Upper limit for the distance from the YSO
when interval
96-100 F5.3 solMass MassE Mass of the envelope
101 A1 --- --- [-]
102-106 F5.3 solMass MassEu ? Upper limit of the mass of the envelope
when interval
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Note (1): J and H represent the JHK' objects and the HK' objects, respectively.
Note (2): the morphology is classified in one of the 3 groups
Asymmetry, Butterfly or Ellipsoidal
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 05-Apr-2010