Perspectives of the LUMINEU program
The present perspectives of the LUMINEU program are the following:
- The crystals delivered in the first two PUMAs will be assembled as scintillating bolometers and operated in the aboveground CSNSM facility. The plan is to couple to the ZnMoO4 crystals, when possible, to the prototype light detectors developed at IAS. A first enriched crystal with a small mass (of the order of 100 g) should also be developed within few months and tested both as a detector and in terms of radiopurity.
- For the completion of the NTD production, contacts have been taken with IAS, CSNSM and IEF (all in Orsay) to discuss the production of the electric contacts on the NTD thermometer. The procedure of production will be fixed during next autumn, and production will start in the end of autumn.
- For the MMC sensors, we will advance towards the most promising sensor concept for the light detectors, i.e. the direct deposit of the MMC sensor and the planar magnetization/readout coil in thin films on the germanium light absorbing wafer. For a fast response, phonon collecting metal films should be added, and the sensor + collector area should be split to several small sub-sensors placed at roughly equidistant locations on the wafer surface. For dark matter heat-and-ionization detectors, direct thin film deposit on the Ge crystal surface should be avoided; a chip with the MMC shall be glued to the crystal and coupled to a readout SQUID via Al bonding wires.