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

The following document lists the file abstract/PHAMMERS_PSNSTAR.abs from catalogue VI/111.
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SCIENTIFIC ABSTRACT
The aim is to obtain accurate monochromatic fluxes for a representative
sample of star classes and spectral types, over a wide wavelength range.
The stars should be normal in the sense that they are single and have no
known infrared excesses. The recognition of 'normal stars ' which have
infrared excesses less than 1%  is not easy. A few stars with large
excesses, such as Vega, are known to exist, but little
is known on the proportion with smaller excesses. This study will help
to establish normal stars.
 We wish to compare the measured fluxes with model atmospheres and then use
the Infrared Flux method to determine angular diameters and effective
temperatures.

OBSERVATION SUMMARY
We wish to observe stars with a 2.2 micron fluxes of  between
2700Jy and 30Jy. The fluxes have been estimated by  extrapolating these fluxes
to longer wavelengths assuming a normal photosphere. If the star has an excess
these fluxes will be under estimates. At 10 microns the flux range is 272Jy to
3Jy and at 100 microns it is 3.7 to 0.04Jy.

We wish to obtain photometry using PHT-P. We wish to use 5  filters  aperture
combinations in the PHT03 AOT. They  are 10 microns/13.8", 16 microns/18",
25 microns/23",  60 microns/52" and 100 microns/99". The fluxes from the
stars will be far larger than the background at the shorter wavelengths,
the integration times will be 32 seconds and staring mode will be used.
 However at the longer  wavelengths (60 and 100 microns) chopping will
be required and for the  fainter objects an increased integration time is
needed to obtain high S/N.

We wish to uses both gratings of PHOT-S. The integration for the brighter
stars will be 32 seconds but this will be increased to 128 seconds for the
faintest stars.

The SWS spectra are required to identify and measure blocking features. 
We require medium resolution and the AOT SWS01 with a total integration
time of 12.7 mins will be sufficient. 



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