approach. The numerical COde for Solar Irradiance (COSI model) has been used. Several
comparisons between ATLAS 3, SOLAR, WHI, and COSI theoretical spectrum showed an overall
agreement taking into account the uncertainties of these spectra. However, at some small
wavelength domains, differences (expressed in terms of percentages) were above the mean.
These cases were explained either by a low signal to noise ratio, instrument uncertainties, and
limitation in lines list to simulate the solar spectrum. These spectra were used to derive the
temperature of the solar atmosphere. Up to 1 100 nm, these temperatures were in agreement
within 50 K. Above 1 100 K, measured spectra provided consistent temperature, however,
greater than the COSI temperature and reaching 200 K. At the contrary, SOLAR 2 spectrum
provided temperature smaller by 400 K than the temperature derived from the other
experimental spectra.
PUBLICATION(S)
Thuillier MG, Bolsee D, Schmidtke G, et al. The solar irradiance spectrum at solar activity
minimum between solar cycles 23 and 24. Solar Physics. June 2014;289(6):1931-1958. doi:
10.1007/s11207-013-0461-y.
Schmidtke G, Froelich C, Thuillier MG. ISS-SOLAR: Total (TSI) and spectral (SI) irradiance
measurements. Advances in Space Research. January 2006;37(2):255-264. doi:
10.1016/j.asr.2005.01.009.
This investigation is ongoing and additional results are pending publication.