Description |
scientific abstract the purpose of this proposal is to study circumstellar dust, building on the iras discoveries by extending measurements to longer wavelengths, improving resolution, and to interpret the iras data through mapping observations. a wide variety of stars are nominated for observation by isophot, since many types of star have been found to have circumstellar dust, either as disks or shells. isophot gives us the opportunity to investigate the structure of the dust around these stars, using multi-aperture and mapping observations, and to investigate deviations of the energy distribution from that expected from a black-body with long wavelength multi-filter observations. spectra will be taken of all the brighter stars, to look for dust features. observation summary the proposal is split into three parts, this is part 2 (c-rich stars). it is planned to obtain more accurate coordinates for the sources in this proposal. the background positions used for the multi-aperture photometry may be updated later. the times used in this proposal are calculated using the cookbook. p22 is executed with 4 filters for 32s integration time, c_60, c_100, c_135, c_200. p04 is executed at 60um for 32s for all stars, and the background field has 64s integration time. p40 is executed with 32 second integration. nir photometry uses the 7.3, 10.0, 12.8, 16.0 filters. the diffraction limited aperture at the longest wavelength observed is used. y cvn, v aql: nir, 25, 60, 100 um filters used with pht03 r crb, ry sgr, su tau: uses 6 filters in pht22, c_60, c_70, c_100, c_120, c_135, c_200, chopped chi cyg, w aql, t dra, v hya, r lep, sig1 ori, r for: use rectangular chopping in pht22 |