GAMMASPHERE information, HK data

K - fold, number of detectors that fired in GS

In the event filter formatters (EFFs), a time gate is normally applied to the events where there are dirty germaniums and clean BGO events. This time gate is set in the file /usr/eff/user.eff -- see the FAQ for details. Thus, normally, the line in the event header that contains the number of 'dirty germaniums' and 'clean BGO' detectors that fired in the event are time gated by the prompt time window.

There is a problem with the above rule is we write any dirty germanium detectors or clean BGO detectors out -- since then those multiplicities are used to untangle the actual data on the data tapes. To overcome this problem the expanded rule is:

Thus, if neither dirty germaniums or clean BGO are written out, to get the total prompt multiplicity of an event, you need to add

(For gs_skim users: the latter two numbers are summed and put in the first word of the skimmed-event so you only need to add the prompt-gated clean germaniums to get the total multiplicity, tmul)

H - summed energy observed in GS

In the event header, the last two words are the sum of energy seen in the germanium detectors and BGO detectors. Both of those energies are time gated with the EFF time gate (see the FAQ for details on how to set or change this time gate) The germanium summed energy is from the low-res germanium signal and both clean and dirty germaniums are add added with the time gate. Thus, for the summed energies for both germanium and BGO detectors, all time gating has been done by the EFFs (no matter what data is written to tape). For the calibration coefficients of the two summed energy signals, see the event header documentation

(for gs_skim users: as of 10/23/9, the above energies have been added up as etot=(10*eBGO+16*ege)/551 and stored in the first word of the skimmed event)

If you find errors in this GAMMASPHERE documentation; please send E-mail to

GS HK response functions/matrixes

Here is an example of a response function for Gammasphere when there are no heavy-mets in front of the BGO detectors

Here is another example of a response function for Gammasphere when there are no heavy-mets in front of the BGO detectors

Hold shift key down when you click on the response functions to download.

If you have other HK response functions you would like to share, send them to me so I can put them on this page.