The Gran Sasso team managed to run two small size prototype detectors of arch-PbWO4. One detector is equipped with a Ge-NTD, and it is featuring a sub-keV baseline energy resolution. This detector will be used for low-energy studies. The other detector is equipped with a TES (same as this) and it will help us in benchmarking the electronics noise at the few pA/sqrt(Hz).

After over two months of background characterization, we set up our alpha screening stations. We are now investigating the surface activity of our Archaeological-Pb samples, produced using the same procedure as the bricks made in May 2024. The background rate of our detector in the 3-11 MeV region is below 0.015 c/h/cm².

We started the gamma-screening of the first 100 kg batch of the purified Archaeological Roman Pb at LNGS.  We are using one of the best HP-Ge detector available at LNGS, and despite this the measurement will go on for at least 3 months. We are expecting to observe nothing! Roman Pb has an extremely small content of residual natural radioactivity.

Soon we will post the results of the assay. Stay tuned!

UPDATE (Oct2024): unfortunately due to an UPS failure the measurement was stopped. Data will be available soon!

At the UNIMIB Physics department we purified and processed the first batch of 100 kg of Archaeological Pb. The main goals were: improve the chemical purification, and produce regualr shape bricks of Pb. These will simplify the following step: the gamma-screening at LNGS with a gamma spectrometer.