Compton Observatory Science Report #182, Tuesday, June 9 1995 Chris Shrader, Compton Observatory Science Support Center Questions or comments can be sent to the CGRO SSC. Phone: 301/286-8434 e-mail: NSI_DECnet: GROSSC::SHRADER Internet: shrader@grossc.gsfc.nasa.gov Guest Investigator News The Cycle-5 Proposal Review was held two weeks ago. The time-line committee meeting will occur later this month, after which all proposers will be notified of the peer-review evaluation of their proposals - hopefully letters will go out in the mid-July time frame. As noted in some of the Instrument Team reports, the Third Compton Symposium will be held in Munich, Germany next week - many exciting results are expected. Copies of a preprint entitled "Recent Results From the Compton Gamma Ray Observatory", are available from the GRO-SSC (contact Sandy Barnes at barnes@grossc.gsfc.nasa.gov). The article will appear in the July issue of PASP (It will also be available electronically shortly - today if I get a late burst of energy). Need help regarding CGRO analysis software, data, or policy issues??? There is now a mail exploder called grohelp, through which your questions will get promptly distributed to the appropriate person(s) for expeditious response. Just send e-mail to "grohelp@ascasrv.gsfc.nasa.gov". Congratulations to Jerry Fishman, who will present the Rossi Prize Lecture at the Pittsburgh AAS Meeting next week, and to Jay Norris will receive Goddard Space Flight Center's Annual Lindsay Prize award at this afternoon's colloquium. Both Jerry and Jay are honored for their work on Gamma-Ray Burst research. Instrument Reports EGRET EGRET operations were normal this monthly period. Delivery of the final phase 3 data to the GRO SSC remains on schedule and delivery of the phase 4 preliminary data to the GRO SSC is now running ahead of schedule. Interaction with guests investigators continues at a good level. The Second EGRET Catalog of High Energy Gamma-Ray Sources has been accepted by the Astrophysical Journal Supplement, and preprints are being mailed to the standard mailing list. There are now over fifty AGN identifications among the sources in the catalog. There are also approximate upper limits for gamma-ray sources at any point in the sky. The catalog uses an improved model of the diffuse galactic gamma radiation, which is now available through the GRO SSC. The catalog tables are available by anonymous ftp from gamma.gsfc.nasa.gov, subdirectory pub/second-catalog. The format is plain ASCII. The figures, including the full set of source location maps, are also available in PostScript format at this same location. The map of upper limits for any point in the sky is available in FITS format. There has also been a detection of another puslar, PSR B1951+32. A paper on this topic by Ramanamurthy et al. has been accepted by the Astrophysical Journal. Another paper, also accepted by the Astrophysical Journal, is concerned with a long term study of high energy gamma-ray emission from Vela, Geminga, and Crab pulsars. Preprints of these last two papers also exist and are being mailed to the standard mailing list. An observation of the Galactic center region has just begun and will continue through July 4, 1995. OSSE OSSE operations are normal. Detector motor drive #1 continues to operate without error. Since 10 April, the slewing response to BATSE burst triggers has been disabled, since the BATSE burst trigger is set to the low energy (25-100 keV) band. An OSSE paper on PSR 1259-63 (Grove et al. ApJL) has recently been accepted. The observed unpulsed power law emission near periastron, consistent with an extrapolation of contemporaneous ASCA data, is the first strong evidence for shock-powered emission in a binary system. OSSE team members are preparing a large number of presentations for next week's Compton Symposium, including summaries of the results of the just completed searches for lines from Cas A and the Orion region. Recent observations are listed in the following table. View period Dates Target (owner) 419.5 9-23 May Orion A+B (GI H. Bloemen) Cas A (PI team) 420 23 May - 6 Jun Orion A+B (GI: H.Bloemen) Cas A (PI team) 421 6-13 Jun Gal plane (355,0) (PI team) SMC X-1 (PI team) Data from viewing periods 318.1, 321.1, 321.5, 317, and 319.0 were delivered to the Compton GRO Science Support Center archive in the last month. The targets during these periods were Cyg X-1, NGC 253, A0535+26, PSR 0540-69, 3C120, CTA 102, QSO 0716+714, and PKS 2155-304. COMPTEL The COMPTEL instrument is performing well and continues routine observations. The following papers by the collaboration are currently in press. Most have recently been distributed as preprints, and will also soon be available as postscript documents via either anonymous ftp from unhgro.unh.edu (cd to the pub/papers directory), or via the COMPTEL WWW pages accessible from the COSSC home page (at URL http://cossc.gsfc.nasa.gov/cossc/cossc.html). "COMPTEL detection of two spatially-coincident gamma-ray bursts" (Kippen et al.); "COMPTEL search for 22-Na emission from recent novae" (Iyudin et al.); "The gamma-ray burst GB 920622" (Greiner et al.); all of the above will appear in Astronomy and Astrophysics. In addition, a review paper on "Radioactive 26-Al in the Galaxy: Observations vs Theory" (Prantzos and Diehl) will appear in Physics Reports. The collaboration has recently forwarded to the COSSC public data archive at the NASA/GSFC low-level and first high-level COMPTEL data products for the CGRO viewing periods 301 to 313 inclusive. There will be presentations by members of the collaboration at the June meeting of the Solar Physics Division of the AAS in Memphis, and the general meeting of the AAS in Pittsburgh. Numerous team reports will also be presented at the Third Compton Symposium next week in Munich, for which final preparations are nearing completion. A semi-final program of the agenda has recently been distributed. The latest information regarding the Symposium can be found at the following URL on the Web: http://cgro95.mpe-garching.mpg.de/cgro95.html. BATSE Several BATSE team scientists will be presented papers at the 3rd Compton Symposium in Munich. Bill Paciesas will be giving a BATSE overview, and present observations of GRS 1915+105. David Crary will present a long term power spectral study of Cyg X-1. Mark Finger will present a study of the resent outburst of the x-ray binary 2S 1417-624. Nan Zhang will present observations of the burster 4U 1608-522, and the newly discovered x-ray binary GRO J1849-03. Jerry Fishman will be receiving the Rossi Prize at the AAS meeting in Pittsburgh. At the meeting, talks or posters will be given by Tom Kosshut, Geoff Pendleton, Chyssa Kouveliotou, and Bob Mallozzi. Several papers by members of the BATSE burst have been accepted for publication: "Do Gamma-Ray Burst Sources Repeat?" by C.A. Meegan, D. Hartmann, J. Brainerd, M.S. Briggs, W.S. Paciesas, G.N. Pendleton, C. Kouveliotou, G.J. Fishman, G. Blumenthal, and M. Brock, will appear in the June 10 issue of ApJ. "Gamma-ray Burst Precursor Activity As Observed With BATSE" by T.M. Koshut, C. Kouveliotou, W.S. Paciesas, J. van Paradijs, G.N. Pendleton, M.S. Briggs, G.J. Fishman, and C.A. Meegan will appear in the Oct 10 issue of ApJ. "Galactic Gamma-ray burst Models: Constraints on the Intrinsic Luminosity Function" by J. Hakkila, C.A. Meegan, G.N. Pendleton, J.M. Horack, M.S. Briggs, W.S. Paciesas and A.G. Emslie, will appear in the November 20 issue of ApJ. The following sources have been detected by the BATSE pulsed source monitor since April 1st : Her X-1, Cen X-3, 4U 1626-67, 2S 1417-624, OAO 1657-415, GX 1+4, Vela X-1, and GX 301-2. To provide enhanced sensitivity to soft gamma-ray repeaters the BATSE burst trigger has operated on the 25-100 keV energy range since April 12. As of TJD June 8th BATSE has detected 1296 gamma-ray bursts out of a total of 3527 on-board triggers in 1507 days of operation. There have been 757 triggers due to solar flares with emission above 60 keV, 9 due to SGR events, and 48 due to terrestrial gamma-ray flashes.