The Impact of Stellar Model Spectra in Disk Detection
  We present a study of the impact of different model groups in the detection
of circumstellar debris disks. Almost all previous studies in this field have
used Kurucz model spectra to predict the stellar contribution to the flux at
the wavelength of observation thus determining the existence of a disk excess.
Only recently have other model groups or families like Marcs and
NextGen-Phoenix become available to the same extent. This study aims to
determine whether the predicted stellar flux of a disk target can change with
the choice of model family - can a disk excess be present in the use of one
model family whilst being absent from another? A simple comparison of Kurucz
model spectra with Mrcs and NextGen model spectra of identical stellar
parameters was conducted and differences were present at near-infrared
wavelengths. Model spectra often do not extend in wavelength to that of
observation and therefore extrapolation of the spectrum is required. In
extrapolation of model spectra to the Spitzer MIPS passbands, prediction of the
stellar contribution differed by 5 % at 70mum for F, G and early K spectral
types with differences increasing to 15% for early M dwarfs. Analysis of the
Spitzer MIPS 24mum observations of 37 F, G and K solar-like stars in the
Pleiades cluster was conducted. In using Kurucz model spectra, 7 disk excesses
were detected while only 3 and 4 excesses were detected in using Marcs and
NextGen-Phoenix model spectra respectively.
