===========================================================================
==> Time for  this proposal is to be transferred from  CBONOLI.FIRBAR(1-2)
==> This proposal requests an upgrade from Priority 3 for CBONOLI.FIRBAR(1-2)
===========================================================================
The proposal mentioned above (actually two parts of the same proposal), aimed
at observating a sample of 13 barred galaxies with PHOT, has been assigned by
OTAC 30000sec with Priority 2  and 32400sec with Priority 3. During phase 2 we
used 27693sec of Priority 2. Here we want to performe a time upgrade of  our
Priority 3 observations and and to recover the remaining 2307sec from Priority
2. Related observations in the Guaranteed Time (GT) with CAM will provide
fruitful information on the distribution of the warm dust inside HII regions
and of the PAHs emission. In the FIRBAR proposal we suggest to further
investigate the emission properties of these bright infrared sources looking at
different wavelenghts to discriminate the temperatures of dust components.
Hydrodynamical studies show that the gravitational potential due to the
presence of the bar exerts a torque which drives an inflow of the gas along the
bar toward the center. In the presence of an Inner Lindblad Resonance, this gas
accumulates in a nuclear ring, where active star formation takes place. The
conclusion is that bars are playing a major role in triggering star formation.
It is therefore not surprising that analyses of starburst galaxy samples showed
that there is a preponderance of bar features.
Following Soifer (1987), barred galaxies are the most luminous infrared sources
among normal galaxies; in fact, around 50% of their total luminosity is emitted
at long wavelengths, while this percentage is about 30% for normal spirals. As
suggested by previous works on this subject (Mazzei et al, 1992, 1994), looking
at suitables infrared spectral ranges, we can recover the current value, as
well as the past trend of the star formation rate.