Aris L S Angelis

A Measurement of Inclusive pi0 Production at Large p(T) from p p Collisions at the CERN ISR

Abstract The inclusive cross section for larger p T π 0 production near 90° in p-p collisions at the CERN ISR is presented for centre-of-mass energies 30.7, 53.1 and 62.4 GeV. The data are inconsistent with scaling of the form p T − n F ( x T ), with constant n or with n allowed to depend on x T = 2p T / s . For s = 53.1 and 62.4 GeV , the value of n found for 3.5 p T c is n = 8.0 ± 0.5, in agreement with previous experiments. However, for 7.5 p T c the value becomes n = 5.1 ± 0.4.

The total neutral energy spectra in the central region of α−α, d−d and p−p interactions at sNN = 31 GeV per nucleon pair at the CERN ISR

The spectra in total neutral energy, ETOT0, have been measured in pp, dd and αα collisions at centre-of-mass energy per nucleon pair, sNN, of 31 GeV. The range in ETOT0 covered was 1 to 19 GeV in pp, 18 to 24 GeV in dd and 1 to 34 GeV in αα interactions. The ratio of the αα to the pp spectra rises monotonically from 7 at ETOT0 = 1.5 GeV to 105 at ETOT 0 = 19 GeV. Since ETOT0 is the sum over many particles in the detector, it is directly sensitive to multiple nucleon-nucleon collisions in the interacting α particles. The αα spectrum in the range 8 < ETOT0 < 17 GeV is consistent with being described by a simple model of 4 simultaneous nucleon-nucleon collisions with a cross section about equal to 10% of the observed αα interaction cross section. The spectrum of ETOT0 above 17 GeV is even flatter than this extreme case where four nucleon pairs are interacting.

A Study of Final States Containing High-pT πo's at the CERN ISR

A large solid-angle apparatus consisting of a superconducting solenoid magnet, cylindrical drift chambers, and two arrays of lead-glass counters is used to examine particles associated with a high transverse momentum trigger in pp interactions at the CERN ISR. The trigger is given by energy deposition in the lead-glass arrays centred at 90°. Results on particle correlations and on jets are presented for interactions at √s = 62.4 GeV and in the trigger transverse momentum range 3 < pT < 11 GeV/c.

A comparison of the production of π0-mesons in pp and pp interactions at the CERN ISR

Abstract A comparison of p p and pp interactions s =52.7 GeV at the CERN ISR. The quantities compared were the charged and neutral multiplicities, the total neutral transverse energy, ΣET, up to 12 GeV, and the single π0 inclusive cross section up to p T = 5 GeV c . No significant differences were observed.

A Measurement of the transverse momenta of partons and of jet fragmentation as a function of ? in p‐p collisions (CCOR Collaboration)

A large solid‐angle apparatus consisting of a superconducting solenoid magnet, cylindrical drift chambers and two arrays of leadglass counters was used to examine particles associated with a high transverse momentum trigger in p‐p collisions with three ?s values at the CERN ISR. The trigger was given by energy deposition in lead‐glass arrays centered at 90°. The trigger transverse momentum range covered was 3<pTrig<11 GeV/c. Results are given for pout for both individual charged particles, and also for the sum of charged particle momenta in the hemisphere opposite to the trigger. Mean values are then deduced for the parton transverse momentum kT, and for the jet fragmentation momentum jT. Results of a jet analysis are also presented.

A Measurement of the transverse momenta of partons and of jet fragmentation as a function of ? in p-p collisions (

A large solid‐angle apparatus consisting of a superconducting solenoid magnet, cylindrical drift chambers and two arrays of leadglass counters was used to examine particles associated with a high transverse momentum trigger in p‐p collisions with three ?s values at the CERN ISR. The trigger was given by energy deposition in lead‐glass arrays centered at 90°. The trigger transverse momentum range covered was 3<pTrig<11 GeV/c. Results are given for pout for both individual charged particles, and also for the sum of charged particle momenta in the hemisphere opposite to the trigger. Mean values are then deduced for the parton transverse momentum kT, and for the jet fragmentation momentum jT. Results of a jet analysis are also presented.