The following document lists the file abstract/AMOORWOO_QSOS.abs
from catalogue VI/111.
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SCIENTIFIC ABSTRACT: We propose to take deep infrared images of quasars using the ISOCAM. The aim is to quantify for the first time, the nature of an extended near-mid infrared component surrounding some quasars. Very recent near infrared imaging obtained with ir-arrays attached to ground-based telescopes, reveal the existence of a red extended component around several PG quasars. This may be associated with the stellar component in the host galaxy, or possibly with an interaction between the quasar and a companion galaxy. If this extended component is due to a large scale burst of extra-nuclear star formation, the mid-infrared observations will provide a particularly useful constraint, since the emission will be due to re-radiating dust grains with peak emission well suited to ISO observations. The morphology of the extended ir-emission will also test the popular theory of collimated continuum emission from galactic nuclei, since if it originates from re-radiating dust heated by the nucleus it may trace out a cone defined by the heating flux, with apex at the nucleus. OBSERVATION SUMMARY: In order to obtain some crude spectral information, two filters will be used: LW2 (5-8.5 microns) and LW3 (12-18 microns). The pixel scale will be 1.5 arcsecond. The QSOs have IR fluxes between 0.120 and 2 Jy and the main difficulty of this program will be the deconvolution of the image PSF in order to detect any faint extended structure as close as possible of the QSO. Eight quasars will be observed, plus two reference stars (observed in the same way in order to accurately determine the image point spread function). We will use AOT #3 (beam switching mode) in order to accurately subtract the background. The integration times on all fields (qsos and reference stars) will be 25 minutes with LW2 and 20 minutes with LW3. In this configuration, a surface brightness of 100 microJy per square arcsecond should be detected with S/N around 10 in LW2 and 15 in LW3. LINKED OBSERVATIONS: (if any, otherwise drop this line) FIXED TIME OBSERVATIONS: (if any, otherwise drop this line) CONCATENATION: (if any, otherwise drop this line) To get the best possible PSF deconvolution, each of the two reference stars will be concatenated to a quasar so that the PSF is observed at the same time.