Photos during the November/December 2010 upgrading

During the upgrading on Nobember/December 2010: the shield has been opened in HP Nitrogen atmosphere in order to replace the 50 low background PMTs with new ones having higher quantum efficiency.

Working in HP Nitrogen atmosphere:




Working on the installation
of new PMTs - 1 -

Working on the installation
of new PMTs - 2 -

Assembling of the new PMT with its divider

New PMT enclosed in its shaped copper housing

A view of a new PMT