D. Broszkiewicz

Dark matter search with a low temperature sapphire bolometer

Abstract A dark matter detection experiment using a low temperature 24 g sapphire bolometer is presented. The low radioactive background cryogenic facility, installed in a deep underground site, is described, as well as the low-noise read-out electronics and the data analysis. From the energy spectrum, measured down to 4 keV, exclusion plots are derived for WIMPs having coherent vector coupling or axial coupling to ordinary matter.

Dark matter search in the Fréjus Underground Laboratory EDELWEISS experiment

Abstract The status of the EDELWEISS experiment (Experience pour DEtecter Les Wimps En SIte Souterrain) in the Frejus Underground Laboratory is reported. The cryostat is described with the main lines of low radioactivity design and readout system. The first results using bolometer detectors together with the measurement of the internal radioactive background using a 100 cm 3 classical Ge crystal are reported. The future program of the experiment will be outlined.

Conventional readout electronics for superheated superconducting grains — First experimental results

Abstract Complete analysis of the electronics for a superheated superconducting grains detector is presented. The designed electronics readout is presented as a good tool to understand grains transiting signals. First experimental results for very small grains, less than 8 μm size, and transiting time evaluation are presented.

Hot Electrons Effect in a #23 NTD Ge Sample

We have measured thermal properties of Neutron Transmutation Doped Ge (type #23 from E. E. Haller) at very low temperatures (down to 20 mK). Both R versus T characteristics and thermal decoupling were considered. We show that, for our sample, the thermal decoupling can be well described with the hot electron model. Our results are consistent with those obtained for other doping concentrations NTD Ge. Finally, we compare the two decoupling mechanisms (electron-phonon and phonon-bath) and show that they are comparable in magnitude for standard running conditions of bolometers.

First results of the EDELWEISS experiment

The ethical question about the information technologies We refer here to Aristotles definition of ethics to illuminate some practices generated by information technology. For example, the accumulation of documents (temptation to “possess” resources ), the problem of incorporating user – generated information within the project phases (problem of integrating alternative approaches), the assertion about the absolute freedom to make use of the ideas accessible on the web (the individuals interest takes precedence over laws of property); the decisive significance imputed to knowledge as opposed to imagination or affectivity. The denial of the corporeal in the world of the intellect is a philosophical point of view with its roots deep in gnosticism.