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==> This proposal requests an upgrade from Priority 3 for PROP_B_A.PANDREAN
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We propose to use PHOT to carry out measurements at wavelengths of 11.5, 60 and
160um of a complete sub-sample of optically selected bright quasars taken from
two recently completed multicolour (U,B,V,R,I) quasar surveys.
The optical fluxes are in the range 15 < B < 17, partially overlapping those of
the PG survey, but with a much better photometric accuracy (sigma_B ~ 0.1mag).
Our samples show that the true surface density of optically-selected quasars in
the range 15<B<16.5 is significantly higher (a factor 3) with respect to the PG
survey. No other complete quasar surveys sample such bright fluxes.
ROSAT and VLA observations were already obtained for whole bright sub-sample.
With our new estimation of the B-band space density of quasars, our main aim is
to estimate, for the FIRST time, the bivariate luminosity function. This will
tell us how the optical-infrared relation for quasars changes as a function of
both luminosity and redshift. Using this relation we can derive the relative
strengths of the different components responsible for infrared emission and
disentangle the dependences on redshift and luminosity.
Note that this project cannot be carried out using IRAS data because of the low
sensitivity of this survey and the LACK of any COMPLETE quasar sample observed
by this satellite.
Photometry at different FIR wavelengths will measure the spectral energy
distribution (SED) of the population and address the issues of the relative
importance of thermal and non-thermal emission. The inference of the amount of
dust in these objects will have profound impact onto the question of the host
galaxy formation.
Only 6 sources are in the Reserved List of ISO-PHOT and here we propose to
upgrade those AOTs concerning the remaining 26 objects with Bmag<16.7 to BUILD
A HOMOGENEOUS SAMPLE at this magnitude. Only in this way, significant
statistics can be obtained to achieve the scientific aims of this project.