Progress report on the SLD cerenkov ring imaging detector
We describe test beam results from a prototype cerenkov Ring Imaging Detector (CRID) for the SLD experiment at the SLAC Linear Collider (SLC). The system includes both liquid and gas radiators, a long drift box containing gaseous TMAE and a proportional wire chamber with charge division readout. Measurements of the multiplicity and detection resolution of cerenkov photons, from both radiators are presented. Various design aspects of a new engineering prototype, currently under construction, are discussed and recent R&D results relevant to this effort are reported.
Development of a low noise preamplifier for the detection and position determination of single electrons in a Cerenkov ring imaging detector by charge division
A preamplifier using a low-noise dual-gate MOSFET front end has been designed, built, and tested. It performs well, having a noise level of about 500 electrons RMS at a shaping time of 65 ns. It is linear over its entire range to better than 1%. It has been used to detect single photoelectrons in a Cerenkov ring imaging detector. A single channel contains preamp, RC-CR shaper, gain adjustment, driver, and calibration circuitry. The circuit is described in detail, and results of noise and linearity measurements are presented. >
On the ontology of particle mass and energy in special relativity
Einstein claimed that the fundamental dynamical insight of special relativity was the equivalence of mass and energy. I disagree. Not only are mass and energy not equivalent (whatever exactly that means) but talk of such equivalence obscures the real dynamical insight of special relativity, which concerns the nature of 4-forces and interactions more generally. In this paper I present and defend a new ontology of special relativistic particle dynamics that makes this insight perspicuous and I explain how alleged cases of mass–energy conversion can be accommodated within that ontology.