Here is a description of RISE:

in kumac file one has to specify:

setenv RICH_CONFIGDIR $HB/$HBVERS/geo/rich

and in usevnt.F (after dgevnt()) one has to call: rcrings();

The program will initialize itself during the first call and no other initialization is necessary.
The reconstructed information is stored in RSEG table:

r.xf = reconstruction space, horizontal angle
r.yf = reconstruction space, vertical angle

r.time= Cherenkov angle
r.dtim= beta (=v/c) of particle

r.txf = tx of particle
r.tyf = ty of particle

r.chi = chi2 of particle

r.cvf = covariance matrix on tx,ty,Cherenkov angle (instead of Q/p), other elements (x,y) set to zero.

r.fit = MTRA number of reconstructed particle
The note on ring reconstruction idea is HERA-B 98-088

Denis