SUMMARY OF SEQUENCE NUMBER 400011

SUMMARY OF SEQUENCE NUMBER 400011

Title: SPECTRA AND MASS MEASURE FOR THE ULTRACOMPACT BINARY IN NGC 6624

Observer: MURRAY

Subject Category: BH and NS Binaries

Seq: 400011 ObsId: 00098

Long-term Plan bin: 9-Mar-2000

ABSTRACT

We propose to obtain HRC-S LETG spectra of the shortest period binary system know: the11 min WD-NS binary in the globular cluster NGC 6624. This prototype for the double degenerate binaries is bright enough to obtain high S/N spectra with the LETG such that phase-resolved spectra can neasure the abundances in this extreme example of stellar/binary evolution as well as provice the first measure of a NS mass in an actively accreting LMXB in a globular. Comparison with statistical measures will allow constraints on both cluster potential and formation and evolution of thsi exotic system.

TARGET SUMMARY

TARGET NAME RADEC TIME SI GRAT TYPE TC ROLL PRE PHASE MULTI PRI
NGC 6624
275.918750
-30.361111
10.00000
HRC-S
LETG
GTO
no
no
no
no
no
5

IMAGES

(NOTE: RASS images currently only available for targets LTS scheduled on or after Apr-09-2000)

Roll/Visibility

PARAMETERS

Obscat Parameters