J/ApJ/642/972 IR photometry of a star-forming core in NGC 2264 (Young+, 2006)
Spitzer and Magellan observations of NGC 2264: a remarkable star-forming core
near IRS 2.
Young E.T., Teixeira P.S., Lada C.J., Muzerolle J., Persson S.E.,
Murphy D.C., Siegler N., Marengo M., Krause O., Mainzer A.K.
<Astrophys. J., 642, 972-978 (2006)>
=2006ApJ...642..972Y 2006ApJ...642..972Y
ADC_Keywords: Clusters, open ; Stars, pre-main sequence ; Photometry, infrared
Keywords: open clusters and associations: individual (NGC 2264) -
stars: formation - stars: pre-main-sequence
Abstract:
We analyze Spitzer and Magellan observations of a star-forming core
near IRS 2 in the young cluster NGC 2264. The submillimeter source
IRAS 12 S1, previously believed to be an intermediate-mass Class 0
object is shown to be a dense collection of embedded, low-mass stars.
We argue that this group of stars represents the fragmenting collapse
of a dense, turbulent core, using a number of indicators of extreme
youth. With reasonable estimates for the velocity dispersion in the
group, we estimate a dynamical lifetime of only a few times 104yr.
Spectral energy distributions of stars in the core are consistent with
Class I or Class 0 assignments. We present observations of an
extensive system of molecular hydrogen emission knots. The luminosity
of the objects in the core region are consistent with roughly solar
mass protostars.
Description:
Spitzer observations: NGC 2264 was observed with IRAC on 2004 March 6,
and the MIPS observations were conducted on 2004 March 16.
Magellan observations: near-infrared imaging of the IRAS 12 S1 region
was obtained with the PANIC camera on the 6.5m Baade telescope at Las
Campanas Observatory. The broadband images were obtained on 2004
December 30. The molecular hydrogen observations were taken on 2005
February 23.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 93 110 Sources in the IRAS 12 S1 core
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See also:
J/A+A/345/521 : BVRI photometry of NGC 2264 (Flaccomio+, 1999)
J/A+A/355/651 : HRI observations of PMS stars in NGC 2264 (Flaccomio+, 2000)
J/A+A/455/903 : ACIS-I observations of NGC 2264 (Flaccomio+, 2006)
J/AJ/114/2644 : UBVRIHa photometry of NGC2264 (Sung+, 1997)
J/AJ/123/1528 : UBV(RI)C and JHK photometry in NGC 2264 (Rebull+, 2002)
J/AJ/127/2228 : VRI photometry of PMS stars in NGC 2264 OB (Makidon+, 2004)
J/AJ/128/1684 : NGC 2264: VRIHα photometry (Sung+, 2004)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- [YTL2006] Star ID (1)
5 A1 --- n_[YTL2006] [d] "d" for V608 Mon (2)
6- 7 I2 h RAh Hour of Right Ascension (J2000.0)
9- 10 I2 min RAm Minute of Right Ascension (J2000.0)
12- 16 F5.2 s RAs Second of Right Ascension (J2000.0)
18 A1 --- DE- Sign of the Declination (J2000.0)
19- 20 I2 deg DEd Degree of Declination (J2000.0)
22- 23 I2 arcmin DEm Arcminute of Declination (J2000.0)
25- 28 F4.1 arcsec DEs Arcsecond of Declination (J2000.0)
30- 45 A16 --- 2MASSJ 2MASS name (HHMMSSss+DDMMSSs)
47- 51 F5.2 mag Jmag ? PANIC J band magnitude (3)
53- 57 F5.2 mag Hmag ? PANIC H band magnitude (3)
59- 63 F5.2 mag Kmag ? PANIC K band magnitude (3)
65- 69 F5.2 mag 3.6mag ? Magnitude at 3.6µm
71- 75 F5.2 mag 4.5mag ? Magnitude at 4.5µm
77- 81 F5.2 mag 5.8mag ? Magnitude at 5.8µm
83- 87 F5.2 mag 8.0mag ? Magnitude at 8.0µm
89- 92 F4.2 mag 24mag ? Magnitude at 24µm
93 A1 --- f_24mag [abce] Confusion flag on 24mag (4)
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Note (1): Sources detected only in the Spitzer images have numbers>1000
Note (2): "d" indicates that source 54 is V608 Mon.
Note (3): Sources brighter than Jmag=12 Hmag=12 and Kmag=11 are saturated
and we substitute 2MASS photometry.
Note (4): Flag on 24mag is defined as follows:
a = The 24µm flux is confused and contains contributions from source 10.
b = The 24µm flux is confused and contains contributions from
sources 30, 32, 34, 35, 37, 40, and 41.
c = The 24µm flux is confused and contains contributions from
sources 47 and 49.
e = The 24µm flux is confused and contains contributions from the
nearby source 63, which has the more steeply rising SED.
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History:
From electronic version of the journal
(End) Marianne Brouty [CDS] 19-Aug-2008