========================================================================== J/ApJS/184/18 Young stellar clusters Spitzer survey (Gutermuth+, 2009) The following files can be converted to FITS (extension .fit or fit.gz) table2.dat table4.dat ========================================================================== Query from: http://vizier.cds.unistra.fr/viz-bin/VizieR?-source=J/ApJS/184/18 ==========================================================================
drwxr-xr-x 13 cats archive 227 Jan 29 2012 [Up] drwxr-xr-x 2 cats archive 4096 Jan 13 2023 [TAR file] -rw-r--r-- 1 cats archive 479 Dec 19 2022 .message -r--r--r-- 1 cats archive 7603 Mar 15 2012 ReadMe -rw-r--r-- 1 cats archive 1166 Mar 15 2012 +footg5.gif -rw-r--r-- 1 cats archive 3861 Mar 15 2012 +footg8.gif -r--r--r-- 1 cats archive 3526 Apr 9 2010 table2.dat [txt] [txt.gz] [fits] [fits.gz] [html] -r--r--r-- 1 cats archive 374556 Mar 22 2010 table4.dat [txt] [txt.gz] [fits] [fits.gz] [html]
Beginning of ReadMe : J/ApJS/184/18 Spitzer survey of young stellar clusters (Gutermuth+, 2009) ================================================================================ A Spitzer survey of young stellar clusters within one kiloparsec of the Sun: cluster core extraction and basic structural analysis. Gutermuth R.A., Megeath S.T., Myers P.C., Allen L.E., Pipher J.L., Fazio G.G. <Astrophys. J. Suppl. Ser., 184, 18-83 (2009)> =2009ApJS..184...18G ================================================================================ ADC_Keywords: YSOs ; Photometry, infrared ; Associations, stellar ; Surveys Mission_Name: Spitzer Keywords: infrared: stars - stars: formation - stars: pre-main sequence Abstract: We present a uniform mid-infrared imaging and photometric survey of 36 young, nearby, star-forming clusters and groups using Spitzer IRAC and MIPS. We have confidently identified and classified 2548 young stellar objects (YSOs) using recently established mid-infrared color-based methods. We have devised and applied a new algorithm for the isolation of local surface density enhancements from point source distributions, enabling us to extract the overdense cores of the observed star-forming regions for further analysis. We have compiled several basic structural measurements of these cluster cores from the data, such as mean surface densities of sources, cluster core radii, and aspect ratios, in order to characterize the ranges for these quantities. We find that a typical cluster core is 0.39pc in radius, has 26 members with infrared excess in a ratio of Class II to Class I sources of 3.7, is embedded in a A_Ks_=0.8mag cloud clump, and has a surface density of 60pc^-2^. We examine the nearest neighbor distances among the YSOs in several ways, demonstrating similarity in the spacings between Class II and Class I sources but large member clusters appear more dense than smaller clusters. We demonstrate that near-uniform source spacings in cluster cores are common, suggesting that simple Jeans fragmentation of parsec-scale cloud clumps may be the dominant process governing star formation in nearby clusters and groups. Finally, we compare our results to other similar surveys in the literature and discuss potential biases in the data to guide further interpretation. Description: The target sample of the Spitzer survey was primarily selected from the literature compilation of embedded clusters within 1kpc by Porras et al. (2003, Cat. J/AJ/126/1916). The final sample includes all of the embedded clusters in the Lada & Lada (2003ARA&A..41...57L) tabulation within 1kpc, with the exception of Orion and NGC 2264. Table 2 contains the detailed information on the Spitzer data used for each region.