J/AJ/113/1788 Near-IR Imaging Survey of NGC 2282 (Horner+ 1997)
A Near-Infrared Imaging Survey of NGC 2282
Horner D.J., Lada E.A., Lada C.J.
<Astron. J. 113, 1788 (1997)>
=1997AJ....113.1788H 1997AJ....113.1788H
ADC_Keywords: Nebulae ; Photometry, infrared
Abstract:
We present the first near-infrared (JHK) imaging and photometry of a
young cluster associated with NGC 2282, a reflection nebula in
Monoceros. Our observations reveal that the cluster is centrally
concentrated with a surface density that falls as 1/r. The cluster has
a radius of roughly 1.6 pc and contains at least 100 members,
approximately 9% of which exhibit infrared excess emission
characteristic of young stellar objects. Infrared extinction maps
suggest that the cluster is located at the edge of a molecular cloud
and is not heavily reddened. We construct the K-band luminosity
function (KLF) of the cluster and find that it increases with
magnitude up to the completeness limit of our observations
(m_(K)=15.0). The shape of the KLF is similar to those of other young
clusters, such as IC 348 and the Trapezium, which suggest that the
cluster contains a significant population of pre-main sequence stars.
However, at the distance of NGC 2282 (1.7kpc) our observations are
not deep enough to sample the low mass end of the cluster IMF.
Consequently, our KLF does not provide meaningful constraints on
either the age of the cluster or the duration of star formation within
it. On the other hand, the low extinction toward the cluster, its
location at the edge of a molecular cloud, and the relatively small
fraction of infrared excess sources suggest that it is a relatively
evolved cluster of pre-main-sequence stars with an age of
5-10x106 years.
(Copyright) 1997 American Astronomical Society.
For a description of the JHK photometric system, see e.g. GCPD/09
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table3.dat 59 394 1995 1.5 meter telescope CIRIM data
table3.tex 144 417 AASTeX version of table3.dat
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Num Source number
4 A1 --- Note *[a-f] Note flag
5- 6 I2 h RAh Right ascension, J2000
8- 9 I2 min RAm Right ascension, J2000
11- 14 F4.1 s RAs Right ascension, J2000
16 A1 --- DE- Sign of Declination, J2000
17 I1 deg DEd Declination, J2000
19- 20 I2 arcmin DEm Declination, J2000
22- 23 I2 arcsec DEs Declination, J2000
25- 30 F6.2 mag Jmag *? J magnitude (1.20µm)
32- 35 F4.2 mag e_Jmag ? Error in Jmag
37- 42 F6.2 mag Hmag ? H magnitude (1.62µm)
44- 47 F4.2 mag e_Hmag ? Error in Hmag
49- 54 F6.2 mag Kmag ? K magnitude (2.20µm)
56- 59 F4.2 mag e_Kmag ? Error in Kmag
--------------------------------------------------------------------------------
Note on Note:
a - Source 137: nebulous object A
b - Source 177: HD 289120, the central star illuminating the
reflection nebula
c - Source 275: nebulous object B/EQ 0644.3+0121
d - Source 295: nebulous object C
e - Source 314: nebulous object D
f - Source 328: V507 Mon, spectroscopic binary
Note on Jmag:
No color correction has been applied to the J-band magnitudes.
--------------------------------------------------------------------------------
Origin: AAS CD-ROM series, Volume 8, 1997 Lee Brotzman [ADS] 02-May-1997
(End) [CDS] 04-Jul-1997