[en] We have designed, constructed and installed a system that makes an accurate 3D map of the electron drift velocity and measures the space-charge distorting effects in the TPCs of the DELPHI Barrel RICH detector. Details of the design considerations, construction and production are given. (orig.)

[en] The DELPHI detector, installed at LEP, is equipped with RICH (Ring Imaging Cherenkov) counters. The Barrel part incorporates a liquid (C₆F₁₄) and a gaseous (C₅F₁₂) radiator providing particle identification up to 20GeV/c. The Cherenkov protons of both radiators are detected by TPC-like photon detectors. The drift gas (75% CH₄ + 25% C₂H₆) is doped with TMAE, but which the UV Cherenkov photons are converted into single free photo-electrons. These are drifted towards MWPC's at the end of the drift tubes and the space coordinates of the conversion point are determined. One half of the Barrel RICH is now equipped with drift tubes and has provided results from the liquid radiator since spring 1990. The gas radiator has been tested with C₂F₆ as a preliminary filling since August 1990. The data obtained demonstrate the good particle identification potential. For the liquid radiator the number of detected photons per ring in hadron jets is N=8, whereas for muon pairs (single tracks) N=10 has been obtained. For the gas radiator 2.1 photons per track were observed, which demonstrates the good functioning of the focussing mirrors, as the C₂F₆ this is close to the expected value

[en] This paper reports on the DELPHI detector, installed at LEP, equipped with RICH (Ring Imaging Cherenkov) counters. The Barrel part incorporates a liquid (C₆F₁₄ and a gaseous (C₅F₁₂) radiator providing particle identification up to 20GeV/C. The Cherenkov photons of both radiators are detected by TPC like photon detectors. The drift gas (75% CH₄ + 25 %C₂H₆) is doped with TMAE, by which the UV Cherenkov photons are converted into single free photo electrons. These photo electrons are drifted towards MWPC's at the end of the drift tubes and the space coordinates of the conversion point are determined. One half of the Barrel RICH is now equipped with drift tubes and produces results from the liquid radiator since spring 1990. The gas radiator has been tested with C₂F₆ as a preliminary filling since August 1990. The data obtained demonstrate the good particle identification potential. For the liquid radiator the number of detected photons per ring in hadron jets is N=8 whereas for muon pairs (single tracks) N-10 electrons have been observed. For the gas radiator 2.1 electrons per track were observed, which demonstrates the good functioning of the focussing mirrors, as for C₂F₆ this is close to the expected value

[en] NESTOR is a submarine high-energy muon and neutrino telescope, now under construction for deployment in the Mediterranean close to Greek shores. The first floor of NESTOR with 12 optical modules was deployed successfully in March 2003 together with the electronics system. All systems and the associated environmental monitoring units are operating properly and data are being recorded. The status of the NESTOR project is presented. We outline briefly the construction of the deepwater neutrino telescope, properties of the NESTOR site, infrastructure of the project, the deployment of the first floor, and its current operation. The first data are presented and plans for the next steps are summarized