SIMULATION OF POLARIZATION MAPS .2. THE CIRCUMSTELLAR ENVIRONMENT OF PRE-MAIN-SEQUENCE OBJECTS

We simulate near-infrared (J, H, K) polarization observations of young stellar objects (YSOs) in the pre-main sequence phase of their evolut ion with a Monte-Carlo radiative transfer code. The circumstellar envi ronment of the PMS objects is assumed to be a combination of a disk, a bipolar outflow and the cloud core. The density and temperature distr ibutions are based on different analytical models which result from th eoretical work as well as the fitting of observational data. Calculati ons with two different grain models were performed - either with a dif fuse ISM-population (radii between 0.005 and 0.25 mu m) or a populatio n with only larger grains (radii between 0.1 and 1 mu m). The results are presented as a grid of polarization maps, iso-intensity maps and m aps of colour differences. In addition, we discuss spatially unresolve d polarization data. The results should be very useful for the interpr etation of infrared observations of YSOs.