Proceedings of the Particle Physics and Early Universe Conference (PPEUC).
For this paper: postscript up PPEUC CMB index next 1 Introduction...

From simulated sky maps to simulated observations

C. Burigana, D. Maino, N. Mandolesi, E. Pierpaoli,
M. Bersanelli, L. Danese, and M.R. Attolini

Istituto TESRE, Consiglio Nazionale delle Ricerche, Via Gobetti 101, 40129 Bologna, Italy
SISSA, International School for Advanced Studies, Via Beirut 2-4, 34014 Trieste, Italy
IFCTR, Consiglio Nazionale delle Ricerche, Via Bassini 15, 20133 Milano, Italy


We present the basic issues of our simulation program, focusing on some particular aspects. We have generated high resolution maps by using standard spherical harmonics expansion for the CMB fluctuations and by extrapolating available full sky maps to predict the Galaxy emission at frequencies and angular scales appropriate to the PLANCK space mission. These maps have been used to simulate the PLANCK observations and to test its performance. Beam responses are typically not symmetric when they are coupled to a telescope to reach high resolutions, whereas theoretical predictions and standard deconvolution methods generally assume pure symmetric beams. We have simulated PLANCK observations at 30 and 100 GHz for typical scan circles, by convolving simulated maps of the microwave sky with asymmetric beams, to estimate the effect of beam asymmetry on temperature fluctuations measurements. We find that the typical difference between temperature measurements performed by symmetric and asymmetric beams is of few , depending on the eccentricity of the beam response shape and on the beam FWHM. Although this effect is not very high, it may be appreciable and must be reduced by optimising the focal plane.

PPEUC Proceedings
Fri Jul 25 11:36:12 BST 1997