C. Georgiopoulos

A non-numerical method for track finding in experimental high energy physics using vector computers

Abstract A non-numerical vector algorithm is used to reconstruct charged particle trajectories in the E-711 detector at Fermilab. The program is written for a CYBER 205. The vectorized version of the code is approximately 10 times faster than that of the previous scalar codes. The techniques used are applicable to other spectrometers relying on wire chambers for tracking information. The average event takes 7.7 ms to process in vector mode on a CYBER 205 compared to 1.6 s in scalar mode on a VAX-11/780.

Average fraction of jet momentum carried by highP⊥ leading hadrons

The average fraction,, of jet momentum carried by the associated charged leading hadron has been determined in the reactionp+N→h1+h2+X whereN is the target nucleon;h1,h2 are the leading particles of two jets produced at highP⊥. An 800 GeV/c proton beam and 4 nuclear targets: Be, Al, Fe and W were used. The distributions agree with the QCD-parton model predictions for single independent protonnucleon scattering and independent fragmentation process.

A vectorized track finding and fitting algorithm in experimental high energy physics using a cyber-205

Abstract We report on a fully vectorized track finding and fitting algorithm that has been used to reconstruct charged particle trajectories in a multiwire chamber system. This algorithm is currently used for data analysis of the E-711 experiment a Fermilab. The program is written for a CYBER 205 on which the average event takes 13.5 ms to process compared to 6.7 s for an optimized scalar algorithm on a VAX-11/780.