Enhancement of Resonant Thermonuclear Reaction Rates in Extremely Dense Stellar Plasmas

The enhancement factor of the resonant thermonuclear reaction rates is calculated for the extremely dense stellar plasmas in the liquid phase. In order to calculate the enhancement factor we use the screening potential which is deduced from the numerical experiment of the classical one-component plasma. It is found that the enhancement is tremendous for white dwarf densities if the ^{12}C + ^{12}C fusion cross sections show resonant behavior in the astrophysical energy range. We summarize our numerical results by accurate analytic fitting formulae.Comment: 13 pages, 3 figures, accepted for publication in ApJ, replaced with revised versio

Beam tests of a large-scale TORCH time-of-flight demonstrator

The TORCH time-of-flight detector is designed to provide particle identification in the momentum range over large areas. The detector exploits prompt Cherenkov light produced by charged particles traversing a thick quartz plate. The photons propagate via total internal reflection and are focused onto a detector plane comprising position-sensitive Micro-Channel Plate Photo-Multiplier Tubes (MCP-PMT) detectors. The goal is to achieve a single-photon timing resolution of , giving a timing precision of per charged particle by combining the information from around 30 detected photons. The MCP-PMT detectors have been developed with a commercial partner (Photek Ltd, UK), leading to the delivery of a square tube of active area with a granularity of equivalent. A large-scale demonstrator of TORCH, having a quartz plate of dimensions and read out by a pair of MCP-PMTs with custom readout electronics, has been verified in a test beam campaign at the CERN PS. Preliminary results indicate that the required performance is close to being achieved. The anticipated performance of a full-scale TORCH detector at the LHCb experiment is presented

Comparative measurements of the energy consumption of 51 electric, hybrid and internal combustion engine vehicles

This paper presents the measured energy consumption results of a range of efficient vehicles over a 57 miles urban/extra-urban route. The results show that on average the electric vehicles used the least amount of energy (average 0.62 MJ/km), followed by the hybrid vehicles (average 1.14 MJ/km), and the internal combustion engine vehicles (average 1.68 MJ/km). The hydrogen fuel cell vehicle used 1.2 MJ/km. An estimate of CO₂ emissions was also made and it was found that hybrids gave the lowest CO₂ emissions, with around half of the vehicles emitting less than 70 gCO₂/km. The most efficient diesel combustion engine vehicles emitted about 80 gCO₂/km but the majority exceeded 110 gCO₂/km. The majority of electic vehicles emitted 70-110 gCO₂/km assuming a United Kingdom grid average emissions factor of 542 gCO₂/kWh