The 'X' in X-HPD hints at the use of a scintillating crystal as anode of the HPD. The project was kicked off by the C2GT (CERN To Gulf of Taranto) design study. [c2gt]
Our photodetector design comprises an almost spherical glass envelope with a central anode, ideally in the form of a sphere. For practical reasons, a rectangular or cylindrical shape is easier to implement.
The original idea of a Silicon anode was not pursued further because the required segmentation of the Si sensor into sufficiently small pads (capacitance!) would have been too expensive to implement on the prototype level. A variation of the old Philips SMART tube concept, also implemented in the QUASAR tubes of the Lake Baikal experiment appeared as attractive alternative.
Our proto-0 tube consisted of a 1/2 scale X-HPD with a metal cube anode. [proto-0] (photo)
Our latest development is a fully operational 1/2 scale full prototype tube (proto-1) with a cylindrical LYSO crystal anode. [proto-1] (photo). Recent results were presented at the VLVNT08 (Toulons, April 2008) and the NDIP08 (Aix-Les-Bains, June 2008) conferences. [proceedings VLVNT08], [proceedings NDIP08].
In the X-HPD project we collaborate with
- Photonis SAS, Brive (France): Anne-Gaelle Dehaine, Pascal Lavoute, Leo Pierre, Bruno Combettes and Christophe Fontaine.
We are indebted to Bayarto Lubsandorzhiev, Mauro Taiuti and Greg Hallewell for a regular information exchange on conventional and hybrid photo tubes.
Last updated by CJ: 08/07/08
