A Mid-IR survey of L 1641-N with ISOCAM

We present results from our analysis of the Infrared Space Observatory (ISO) data on the L 1641-N outflow region located in the Orion A molecular cloud. The data were obtained with the array camera (ISOCAM) using two broad-band filters, LW2 (6.7 μm), & LW3 (14 μm), and the narrow-band circular variable filter (CVF) which provides low resolution (R=λ/δλ ∼ 40) spectra in the 5–17 μm region. We detect a total of 34 sources in the 7.65 x 8.40 region covered by the broad-band filters. Four of these sources have no reported detection in previous studies of the region. The CVF data are available for only the central 3.2 x 3.2 portion of the total region, providing spectra for the brightest 7 of the sources in that region. We find that the source previously identified as the near-IR counter-part to the IRAS detected point-source (IRAS 05338-0624) is not the brightest source in the wavelength region of the IRAS 12 μm filter. We find instead that a nearby object (within the beam of IRAS and not detected at near-IR wavelengths) outshines all others sources in the area by a factor of ∼2. We submit that this source is likely to be the IRAS detected point source. A comparison of the near-IR (J-H vs. H-K) and mid-IR (H-K vs. [6.7μm]− [14μm]) color-color plots shows that while at near-IR wavelengths only four (4) of the sources show evidence for emission above the values predicted from photospheric emission alone (hereafter referred to as excess emission), at least 85% of