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. =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 5-10x10^6^ years. (Copyright) 1997 American Astronomical Society. For a description of the JHK photometric system, see e.g. 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 (1.20{mu}m) 32- 35 F4.2 mag e_Jmag ? Error in Jmag 37- 42 F6.2 mag Hmag ? H magnitude (1.62{mu}m) 44- 47 F4.2 mag e_Hmag ? Error in Hmag 49- 54 F6.2 mag Kmag ? K magnitude (2.20{mu}m) 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