arXiv subjects

L. Sibley

Publications and source records attributed to L. Sibley.

2 recordsLinked to original sources

arXiv2016

A precise method to determine the activity of a weak neutron source using a germanium detector

A standard high purity germanium (HPGe) detector was used to determine the previously unknown neutron activity of a weak americium-beryllium (AmBe) neutron source. Gamma rays were created through 27Al(n,n'), 27Al(n,gamma) and 1H(n,gamma) reactions induced by the neutrons on aluminum and acrylic disks, respectively. These gamma rays were measured using the HPGe detector. Given the unorthodox experimental arrangement, a Monte Carlo simulation was developed to model the efficiency of the detector system to determine the neutron activity from the measured gamma rays. The activity of our neutron source was determined to be 307.4 +/- 5.0 n/s and is consistent for the different neutron-induced gamma rays.

physics.ins-det↗

arXiv2010

Measuring the Lifetime of Trapped Sleptons Using the General Purpose LHC Detectors

In supergravity where the gravitino is the lightest supersymmetric particle (LSP), the next-to-lightest supersymmetric particle (NLSP) decays to the gravitino with a naturally long lifetime (10^4 - 10^8). However, cosmological constraints favour charged sleptons with lifetimes below a year as the natural NLSP candidate. For this scenario we report a method to accurately determine the slepton lifetime and SUSY cross-section from observation of the decays of sleptons trapped in the material comprising the main detector (ATLAS, CMS). A measurement of the lifetime to 5% is possible after 3 years at nominal luminosity and running conditions. This method is sensitive to the cosmologically preferred stau lifetime of ~37 days and does not require the use of ancillary trapping volumes.

hep-ph↗