Roger W. Bland

The Fréjus nucleon decay detector

Abstract The characteristics, trigger and monitoring systems, data acquisition as well as the performance of the Frejus nucleon decay detector are presented.

Search for Muons from the Direction of Cygnus X-3

We have analyzed muons and multimuons detected in the Frejus underground nucleon decay detector between February 1984 and June 1986. No excess events are observed in the direction of Cygnus X-3, which yields a 90 % confidence level upper flux limit of 0.7 10-12 cm-2 s-1, for an average rock overburden of 5000 hg cm-2 corresponding to energies > 3 TeV. Using the 4.79 hour periodicity of Cygnus X-3, no signal is found in any phase interval.

A search for fractional charges in native mercury

Abstract We have searched 2.0 mg of native mercury for fractional charges. Details of the apparatus and measurement procedure are presented. We find no fractional charges, giving a limit on quark concentration comparable to other experiments carried out on refined materials.

Negative hyperon production at high energy

Abstract With a negative hyperon beam which we have constructed at the CERN PS we have measured the production by 24 GeV/ c proton of K − , p , Σ − , and − , with respect to π − production. Measurements were made on a tungsten target under the following conditions: 1. at a fixed angle of 10 mrad for momenta between 13 and 20 GeV/ c , 2. at a fixed momentum of 17.2 GeV/ c for angles between 10 and 40 mrad. Production was studied on three targets (B 4 C, Al, W) at 17.2 GeV/ c and 10 mrad. Photographs of hyperon decays have also been taken in a prototype streamer chamber.

Superconducting tunnel-junction x-ray detectors with niobium absorbers and aluminum quasi-particle traps

We are developing superconducting tunnel junction devices for use as high-resolution, high- efficiency x-ray spectrometers. We have tested devices with niobium x-ray absorbing layers coupled to aluminum layers which serve as quasiparticle traps. These devices were fabricated photolithographically using a modified niobium/aluminum/niobium trilayer fabrication process. Our first devices have a very thin barrier with specific normal state resistance of 1.5 X 10-6 (Omega) cm2, and also exhibit very low leakage current of 15 nA below 200 mK. The energy resolution at 6 keV is 190 eV FWHM, and is limited both by electronic noise and by the non-linear response of the detector.

Scenario for cold fusion by free quark catalysis

SummaryFleischmann and Pons have reported the astonishing results of watts of power from cold deuteron fusion without large amounts of radiation. We present a scenario in which small numbers of free stable

The ratio …gA/gV… in the decay Σ− → ne−νe

\bar u\bar u = Q

A search for neutrons from fusion in a highly deuterated cooled palladium thin film

anti-diquarks (electric charge of −4/3, mass of a few GeV, and short-range strong repulsion with hadrons) catalyze the deuteron fusion. The reaction channel4He+Q dominates. We predict bursts of neutrons with a 3-body energy spectrum. However, independently of the findings of these experiments, the Q catalysis is attractive in that it could provide large power production, with relatively low radioactivity, if this kind of matter is found and accumulated.