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Dedicated measurements for 154Gd decay

1) First measurement with Pb only

data taken from

GAGG_1.4kV_UG_bkg_AmpX10filtered_20260312_100728.root to

GAGG_1.4kV_UG_bkg_AmpX10filtered_20260316_142013.root

2) Second measurement

Moved the setup to SABRE which has a better shielding (15 cm Pb + 5 cm Cu + N2 flushing), and the data are taken from

GAGG_1.4kV_UG_bkg_AmpX10filtered_20260316_163612.root to

GAGG_1.4kV_UG_bkg_AmpX10filtered_20260317_141213.root

(note: /data/GAGG_1.4kV_UG_bkg_AmpX10filtered_20260316_161411.root is the file with the amplifier connected to the first output)

3) Following the second measurement, the stainless steel holder is removed

This is to understand where the internal contamination comes from

Data are taken from

GAGG_1.4kV_UG_bkg_AmpX10filtered_20260317_142726.root to

GAGG_1.4kV_UG_bkg_AmpX10filtered_20260318_134819.root

4)

Measurement with low background gamma spectrometry (Crystal and PMT) to understand the source of the background

~590 keV bump and Potassium

5) After confirmation that 40K is mainly from the Borosilicate glass window of the PMT, a new measurement campaign has started with Giuseppe's PMT which has a quartz glass, which doesn't have so much 40K contamination inside

Processed data

Each data file lasts ten minutes, and for the measurement with the Pb shielding measured in gator,

cd /data/Reconstructed_GAGG_Pb/

The data taken with Pb + Cu + N2 flushing in the SABRE experiment hub

cd /data/Reconstructed_GAGG_sabre/

After removing the stainless steel holder, and continued the measurement in the SABRE

cd /data/Reconstructed_GAGG_sabre_no_steel_holder/