See attached. The possibility of making optical follow-up observations of GRB's within *minutes* of the gamma-ray event is clearly an enormous scientific opportunity and one which the APO 3.5m is particularly well suited to exploit due to our rapid instrument change capability. The program JH08 (PI Karl Glazebrook, kgb@pha.jhu.edu) will be considered to be in operation as of tonight (6/1/01). If a GRB alert occurs and passes all of the filters which have been put in place by the science team, the on-duty OS (who is a co-investigator) will take over the telescope, slew to the reported position of the GRB, attempt to identify a bright optical transient and, if successful take a series of Echelle spectra (after rotating the tertiary as needed). Fairly elaborate procedures have been worked out and tested as best possible in simulated "dry runs". Obviously, the science program in progress at the time of such an event will be interupted with virtually no warning. Equally obviously, this unexpected interuption will be disconcerting to the observer(s) who is (are) pre-empted. Please understand that there is no other way to obtain this perhaps very important type of data. If you are the observer using the telescope when a GRB interupt occurs, an effort will be made to let you close the shutter and read out the current exposure before the telescope is moved. Please be ready to do so promptly and WITHOUT DISCUSSION OR DEBATE when informed by the on-duty OS. (There will be no time for talking about it since the GRB optical counterpart is expected to be fading on a timescale of minutes or even seconds.) Please then stand-by until the OS has an opportunity to let you know what to expect next. It is possible that no bright optical counterpart will be located and that the telescope will therefore soon be returned to your program; it is also possible that the rest of your time for that night will be lost to ongoing afterglow observations. Any program which loses time to such a no warning GRB interupt will be compensated with future time taken either from JHU's allocation or, in some initial cases, from DD time. Eventually, if this program is successful, a detailed policy for this compensation will be adopted, but for the initial instances, each will be worked out by the Director in consultation with the affected PI and the JH08 PI on a case-by-case basis. This will be done later, not during the night of the interupt. If you have comments or concerns about this project or procedure, please describe them in email sent to the JH08 PI (Karl Glazebrook, kgb@pha.jhu.edu) with copies to your institutional Users Cmte member, Bruce Gillespie and me. Ed Turner +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ ------- Start of forwarded message ------- From: GCN Circulars <gcncirc@lheawww.gsfc.nasa.gov> Subject: HETE Fully-Automated GCN Notices To: mcmillan@apo.nmsu.edu Date: Thu, 31 May 2001 19:27:37 -0400 (EDT) Reply-To: scott@milkyway.gsfc.nasa.gov Affiliation: NASA-GSFC LHEA Project: GCN (GRB Coordinates Network), Circular Service Phone: 301-286-3106 (S.Barthelmy's office, -1684 fax) Content-Type: text/plain; charset=US-ASCII TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1064 SUBJECT: HETE Fully-Automated GCN Notices DATE: 01/05/31 23:09:24 GMT FROM: Scott Barthelmy at NASA/GSFC <scott@lheamail.gsfc.nasa.gov> During the past two weeks, the final testing of HETE-GCN rapid data interfaces was successfully completed. Beginning today, HETE localization releases are fully automatic. HETE Notices will now be promptly distributed through the GCN system. The HETE positions are calculated on-board, down-linked through the 12 Secondary ground stations, forwarded to the HETE Ops computer at MIT, and then forwarded to GCN for distribution to those GCN sites that have elected to receive the GCN/HETE Notices (Alert, Update, Final, and/or GroundAnalysis subtypes). This is the full automated process; there are no humans in the loop, i.e. the minimum possible delay time. The time delays range from 10 sec to 30 sec for the Alert and Update Notices (Updates are the first notice subtype that has position information.) A detailed description of the HETE Notices is contained in: http://gcn.gsfc.nasa.gov/gcn/hete.html and for the socket sites, the packets are defined in: http://gcn.gsfc.nasa.gov/gcn/sock_pkt_def_doc.html It should be stressed that because this is the fully automated, "hands off" processing procedure, there will inevitably be non-GRB triggers included in those sent to the ground and distributed. In fact, during the June-July period, when the Galactic Bulge region is passing through the HETE field-of-view, the majority of the triggers will be non-GRBs. While this is probably not a problem for the automated instrument GCN sites, those sites that involve human effort and/or consumables must understand that many of the HETE Notices will be non-GRBs (eg x-ray bursters, soft gamma repeaters, flaring galactic sources, etc). In general, there will also be follow-up GCN Circulars disseminated for HETE burst events which prove to be confirmed GRBs. These follow-up Circulars will be based on detailed telemetry data which becomes available on the ground 1-2 orbits after the burst, so such HETE Circulars will lag the HETE Notices by a few hours. All those sites who have requested the HETE Notices to be enabled need do nothing. They will receive them. If sites wish to change their configuration, then please send a request. ------- End of forwarded message ------- APO APO APO APO APO Apache Point Observatory 3.5m APO APO APO APO APO This is message 507 in the apo35-general archive. You can find APO the archive on http://www.astro.princeton.edu/APO/apo35-general/INDEX.html APO To join/leave the list, send mail to apo35-request@astro.princeton.edu APO To post a message, mail it to apo35-general@astro.princeton.edu APO APO APO APO APO APO APO APO APO APO APO APO APO APO APO APO APO