BEPPOSAX LECS DETECTION OF COMET C 1995 O1(HALE-BOPP)/

We report the detection of soft X-rays from comet C/1995 O1 (Hale-Bopp ) by the LEGS instrument on-board BeppoSAX on 1996 September 10-11. Af ter correcting for the comets motion, a 7 sigma enhancement was found within 2' of the expected location of the nucleus at much greater than 99.99% confidence. A weak 1.3 sigma enhancement was also found in MEC S data at the same location. The extracted LEGS spectrum is well fit b y a thermal bremsstrahlung model of temperature of 0.29 +/- 0.06 keV - consistent with that observed in other comets. The 0.1-2.0 keV lumino sity has a mean value of 5 x 10(16) erg s(-1) and is a factor of simil ar to 8 greater than measured by the Extreme Ultraviolet Explorer (EUV E) 4 days later. This difference may be related to the emergence from the nucleus on 1996 September 9 of a dust-rich cloud which continued t o expand rapidly over the next few days becoming tenuous by the start of the EUVE observation. There is no evidence for fluorescent carbon o r oxygen emission with 95% confidence limits of 1.0 x 10(15) and 7.8 x 10(15) erg s(-1) to narrow line emission at 0.28 and 0.53 keV, respec tively. This implies that if such lines are present, their total lumin osity must be must be <18% of the 0.1-2.0 keV continuum luminosity.