Chamaeleon’s Cold Cloud Cores

Abstract

ISOPHOT Serendipity Survey (ISOSS) observations of the nearby interstellar medium towards Chamaeleon have revealeda number of cold cloud cores. Far-infraredcolours have been studiedusing ISOSS and IRAS data. 10 very cold cores with colour temperatures T_dust≲13 K have been foundin an 11° x 8° sized region. Comparing the FIR data with radio measurements, all of the very cold cores have high gas column densities, N(H₂) > 10²¹ cm^-2, and 7 out of 10 have low gas temperatures as indicated by T_ex(C¹⁸O) ≈ 8 K.

Based on observations with ISO, an ESA project with instruments funded by ESA Member States (especially the PI countries: France, Germany, the Netherlands and the United Kingdom) and with the participation of ISAS and NASA. Members of the Consortium on the ISOPHOT Serendipity Survey (CISS) are MPIA Heidelberg, ESA ISO SOC Villafranca, AIP Potsdam, IPAC Pasadena, Imperial College London.