Contents of: VI/111/./abstract/FGARZON_PHVSBURS.abs

The following document lists the file abstract/FGARZON_PHVSBURS.abs from catalogue VI/111.
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SCIENTIFIC ABSTRACT
It is our aim to use innovative techniques, made possible by the use
of  ISO instrumentation, to investigate the  parameters that control
the formation of stars in stellar systems. To this end, estimates of
the stellar mass, in several regions of recent star formation, as well
as a variety of measurements revealing the physical properties
(density, metal content, gas to dust ratio, temperature, mass, etc) of
the star forming clouds are envisaged.
 
The project demands a well coordinated investigation of regions of
recent star formation in a variety of galaxies, in order to determine
the  various factors that control the strength of a star formation
burst. Thus, the aim is to infer the total mass in newly formed stars
as well as the properties of the star forming cloud, to determine in
this way a definite correlation. With this aim in mind, we propose to
investigate in detail the far IR properties of star forming regions.
 
OBSERVATION SUMMARY
Each object on the list will be mapped with ISOPHOT-C at wavelengths
sensitive to the presence of dust, like 64, 93 and 152 microns. This
will provide information about the mass of dust, extinction  and the
distribution of ionizing sources. We propose to use filters at 60, 90,
135 and 160 microns. For all sources the expected S/N in the PHT-C maps
should be higher than 10 with 32 second integration time, which is then
selected as a default for the maps except where otherwise is stated.
The observations will use stare mode as as the extent of the objects
can be larger than 180". The HII regions in M33 and M101 galaxies,
which form the target list for the LWS observations, have been
explicity excluded from the PHT-C list since they will be mapped in a
different proposal by Hippelein et al. For 30Dor we propose to map the
central 12x12 arcminutes in the same filters, plus one frame per filter
out of the region for background estimation, due to its huge extension
in the FIR, and use only 16 seconds of integration time per frame,
which will be enough to provide a reasonable S/N ratio.

Optical spectra at the peaks of the emission maps will be taken in
order to determine and model the relative contribution of young stars
in heating the dust. This will allow an estimate as accurate as
posible  of the number of ionizing sources.
 
For bright objects, like the giants HII regions in M33 and M101 listed
below, IR emission lines from the ionized gas will be observed at
selected areas within the star forming regions, using LWS with three
grating positions to map the OIII line at 52 and 88 microns and NIII
lines at 57 microns.  The strength of the lines in all cases is
expected to be high enough to permit minimum integration time.

Target list for LWS
=================== 

Source		     RA	  	    DEC
m33_ngc588 	01 29 56.600   +30 23 30.000
m33_ngc59	01 30 22.600   +30 23 20.000
m33_ngc595	01 30 44.000   +30 26 25.000
m33_ngc604	01 31 43.300   +30 31 54.000
m33_ic131	01 30 23.200   +30 30 02.000
m33_ic132	01 30 26.900   +30 41 19.000
m33_ic142	01 31 05.900   +30 30 02.000
m101_ngc5447	14 00 42.900   +54 30 42.000
m101_ngc545	14 01 15.700   +54 28 59.000
m101_ngc5461	14 01 55.100   +54 33 30.000
m101_ngc5462	14 02 07.000   +54 36 20.000
m101_ngc5471	14 02 43.200   +54 37 57.000
 
 

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