We present results from an ISOCAM survey in the two broadband filters LW2 (5-8.5um) and LW3 (12-18um) of a 19'x16' field called Serp_NH3 centred on the optical group Serpens/G3-G6. A total of 186 sources were detected in the 6.7um band and/or the 14.3um band to a limiting sensitivity of ~2mJy. These have been cross-correlated with the 2MASS catalogue and are all listed in table1. Deep follow-up photometry in the Ks band obtained with Arnica at the Nordic Optical Telescope (NOT) is listed in table2. Deep L' band photometry of selected sources using SIRCA at the NOT is listed in table3. Continuum emission at 1.3mm and 3.6cm was observed with IRAM and VLA, respectively, and deep imaging in the 2.12um S(1) line of H2 was obtained with NOTCam at the NOT. We find strong evidence for a stellar population of 31 Class II sources (listed in table5), 5 flat-spectrum sources, 5 Class I sources (listed in table4), and two Class 0 sources. Our method does not sample the Class III sources.

Cone search capability for table J/A+A/458/789/table1 (ISOCAM 6.7 and 14.3um photometry of the 177 detections in the Ser/G3-G6 complex.)

Cone search capability for table J/A+A/458/789/table2 (Ks band photometry from Arnica/NOT of 1148 sources in a 8'x8' subregion of the ISOCAM coverage.)

Cone search capability for table J/A+A/458/789/table3 (L' band photometry from SIRCA/NOT of 46 sources detected in 12 pointed observations in the Ser/G3-G6 complex.)