Pulse shape discrimination performance of inverted coaxial Ge detectors

Abstract

We report on the characterization of two inverted coaxial Ge detectors in the context of being employed in future 76 Ge neutrinoless double beta (0νββ) decay experiments. It is an advantage that such detectors can be produced with bigger Ge mass as compared to the planar Broad Energy Ge detectors (BEGe) that are currently used in the GERDA 0νββ decay experiment. This will result in lower background for the search of 0νββ decay due to a reduction of cables, electronics and holders. The measured resolution near the 76 Ge Q-value at 2039 keV is 2.5 keV and their pulseshape characteristics are similar to BEGe-detectors. It is concluded that this type of Ge-detector is suitable for usage in 76 Ge 0νββ decay experiments.

Charge-carrier collective motion in germanium detectors for $$\beta \beta $$-decay searches

“…Both plots suggest that a linear correlation could be used to align the A/E values in the bottom and top part of the detector volume. This double peak structure has been first reported in [26,27]. Its origin is connected by our work to the collective effects and the spatial distribution of DEP events within the detector.…”

Characterization of 30 $$^{76}$$Ge enriched Broad Energy Ge detectors for GERDA Phase II

“…Beside this deficit, both siggen and ADL3 codes have meanwhile demonstrated to be reliable tools for the prediction of the full depletion voltage and the appearance of single ‘bubbles’ also in other HPGe detector designs (e.g. for inverted semi-coaxial Ge detectors [34]).…”

“…Besides that, the modified code has become a useful tool within and outside Gerda . For instance, it was used for the characterization and optimization of the standard BEGe detector design [30, 33], for pulse shape simulations of semi-coaxial and BEGe detectors in Gerda Phase I and II, and more recently for pulse shape studies of novel inverted semi-coaxial detectors installed in an upgrade of Gerda Phase II [34].…”

Search for neutrinoless double-beta decays in Ge-76 in the LEGEND experiment

“…Using larger detectors than the MAJORANA DEMONSTRATOR (P-type Point Contact detectors -PPCs -average 0.85 kg) and GERDA (Broad Energy Germanium detectors -BEGesaverage 0.66 kg) would reduce the surface to volume ratio, and require fewer cables and preamplifier front-ends per unit mass, reducing backgrounds. A new detector geometry, Inverted-Coaxial Point Contact (ICPC) detectors [10], have similar performance to PPCs and BEGes (excellent energy resolution and pulse-shape sensitivity) [11], but can be much larger. The current baseline for enriched detectors is 1.5-2.0 kg, with detectors around 3 kg and up to 6 kg being investigated.…”