Computer Science – Sound
Scientific paper
Jan 2010
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2010aas...21548105k&link_type=abstract
American Astronomical Society, AAS Meeting #215, #481.05; Bulletin of the American Astronomical Society, Vol. 42, p.570
Computer Science
Sound
Scientific paper
The J-PEX high-resolution EUV spectrometer has made a breakthrough in capability with an effective area of 7 cm2 (220-245 Å) and resolving power of 4000, which exceed EUVE by factors of 7 and 20 respectively, and cover a range beyond the 170-Å cutoff of the Chandra LETG. The EUV includes critical spectral features containing diagnostic information often not available at other wavelengths (e.g., He II Ly series), and the bulk of radiation from million degree plasmas is emitted in the EUV. Such plasmas are ubiquitous, and examples include the atmospheres of white dwarfs; accretion phenomena in young stars, CVs and AGN; stellar coronae; and the ISM of our own galaxy and of others. However, sensitive EUV spectroscopy of high resolving power is required to resolve source spectral lines and edges unambiguously, to identify features produced by the intervening ISM, and to measure line profiles and Doppler shifts. This allows exploitation of the full range of plasma diagnostic techniques developed in laboratory and solar physics.
J-PEX has flown twice on NASA sounding rockets. In 2001 we observed the isolated white dwarf G191-B2B and detected both ISM and photospheric lines. In 2008 we successfully observed the binary white dwarf Feige 24, but observation time is severely limited with sounding rockets. NASA has approved no new EUV mission, but it is time for one. Here we describe the scientific case for high-resolution EUV spectroscopy, summarize the technology that makes such measurements practical, and present a concept for a 3-month orbital mission, in which J-PEX is modified for a low-cost orbital mission to acquire sensitive high-resolution spectra for 30 white dwarfs, making an important contribution to the study of white dwarf evolution and hence the chemical balance of the Galaxy, and to the understanding of structure in the LISM.
Barstow Martin Adrian
Cruddace Ray G.
Kowalski Michael Paul
Wood Kent S.
No associations
LandOfFree
It's Time For A New EUV Mission does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with It's Time For A New EUV Mission, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and It's Time For A New EUV Mission will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1887893