HR: 0800h
AN: SH31A-1181    [Abstracts]
TI: A high-throughput, high-resolution spectrometer for mapping the heliopause and 3-D Solar Wind using He+ 30.4nm
AU: * Lampton, M
EM: mlampton@ssl.berkeley.edu
AF: Space Sciences Laboratory, University of California, Berkeley, CA 94720 United States
AU: Edelstein, J
EM: jerrye@SSL.berkeley.edu
AF: Space Sciences Laboratory, University of California, Berkeley, CA 94720 United States
AU: Miller, T
EM: timler@earthlink.net
AF: T-Stop Design, 642 Norvell St., El Cerrito, CA 94530 United States
AU: Gruntman, M
EM: mikeg@usc.edu
AF: Astronautics and Space Technology Division, Viterbi School of Engineering University of Southern California, Los Angeles, CA 90089-1191 United States
AB: The He+ ion provides a valuable tracer of solar wind dynamics and the heliospheric boundary. Mapping the heliosphere from 1 AU in 30.4nm with high spectral resolution will open access to the heliopause and reveal the three-dimensional flow of the solar wind. The scattered and emission fluxes are however faint, just a few milli-Rayleighs (mR), which poses a serious limitation on the mapping rate at high signal-to-noise ratio. We explore a spectrometer concept for narrowband EUV emission that offers important advantages over previous designs: high throughput (~1cps/mR), high spectral resolution (several thousand), no moving parts, and modest instrument size and mass. The concept combines a conventional normal-incidence Rowland mount grating and an efficient multilayer coating, with a microchannel plate detector performing two dimensional photon counting. One key innovation is the use of a large-area multi-slit at the spectrometer entrance. This multislit is a one dimensional sequence of open and opaque zones, against which pattern the accumulated spectral image can be correlated to recover the incident spectrum. The other innovation is arranging that each member of the multislit group is curved in such a way that the off-plane grating aberrations (which extend and rotate the image of each object point) do not introduce significant wavelength broadening. The curved slit arrangement yields a large well-corrected image field, and a high throughput for diffuse emission is achieved. This presentation concentrates on the design of the wide-field mount that maximizes the working area populated by the slits. The curved-multislit Rowland spectrometer will have a variety of other applications in astrophysics, aeronomy, and space physics sensing diffuse fluxes with high spectral resolution and sensitivity.
DE: 7594 Instruments and techniques
DE: 2124 Heliopause and solar wind termination
DE: 2164 Solar wind plasma
DE: 2194 Instruments and techniques
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2004 AGU Fall Meeting