Richard Nickerson

Abstract:

Most events with high neutral transverse energy, ET⁰, produced in pp colisions at √s = 62.3 GeV, are jet-like. The evidence for this is presented, based on data collected using an electromagnetic calorimeter covering 90% of 2π in azimuth. The spectrum dN/dET⁰ has been measured over the ET⁰ range from 10 to 35 GeV. Properties of the observed jets are discussed. © 1984.

Abstract:

The spectra in total neutral energy, E^TOT0, 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. © 1984.

Abstract:

The spectrum dN dET0 (ET0 = neutral transverse energy) has been measured with an electromagnetic calorimeter covering 90% of 2π in azimuth. The measurement, performed in pp collisions at s = 62 GeV, covered the ET0 range from 10 to 30 GeV. Evidence is presented that a large fraction of these events are jet-like, the fraction increasing with ET0. © 1983.