Long-Lived Charge Trap Characterization for Rare-Event Searches with Skipper-CCDs

@misc{desai2026longlived,
  title = {{Long-Lived Charge Trap Characterization for Rare-Event Searches with Skipper-CCDs}},
  author = {Ansh Desai and Ana M. Botti and Brenda A. Cervantes-Vergara and Rouven Essig and Stephen E. Holland and Ian Lawson and Steffon Luoma and Santiago Perez and Javier Tiffenberg and Sho Uemura and Yikai Wu and Tien-Tien Yu},
  howpublished = {arXiv},
  year = {2026},
  month = oct,
  doi = {10.48550/arxiv.2610.22418},
  eprint = {2610.22418},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2610.22418},
}

TY  - UNPB
TI  - Long-Lived Charge Trap Characterization for Rare-Event Searches with Skipper-CCDs
AU  - Ansh Desai
AU  - Ana M. Botti
AU  - Brenda A. Cervantes-Vergara
AU  - Rouven Essig
AU  - Stephen E. Holland
AU  - Ian Lawson
AU  - Steffon Luoma
AU  - Santiago Perez
AU  - Javier Tiffenberg
AU  - Sho Uemura
AU  - Yikai Wu
AU  - Tien-Tien Yu
PY  - 2026
DA  - 2026/10/15
PB  - arXiv
DO  - 10.48550/arxiv.2610.22418
UR  - https://arxiv.org/abs/2610.22418
AB  - Skipper Charge-Coupled Devices (Skipper-CCDs) are detectors with sub-electron resolution, allowing them to play a critical role in rare-event searches. A major challenge in experiments using these detectors is understanding and mitigating low-energy backgrounds which impact the single-electron rate. One potential component of the single-electron rate could arise from single-electron charge traps caused by lattice defects. In this work we use a new in-situ technique for generating uniform charge known as ``pixel-pumping'' across the CCD to study single-electron traps in a SENSEI sensor placed underground in the MINOS cavern at Fermilab, which enables sensitivity to long-lived traps with emission times >10^3 seconds, a regime that was previously not accessible. We fully characterize 1787 traps and use this information to estimate their contribution to the single-electron background in SENSEI. Through simulation, we find the characterized population of traps does not significantly impact the single-electron rate. We further identify the energies and cross-sections for traps to which this analysis is sensitive, and compare this with the values that could impact the single-electron rate. This analysis probes a large fraction of this region. However, we also see that a sufficiently numerous hidden population could contribute significantly to the single-electron rate, and new measurement techniques will have to be devised in order to fully rule out this population.
ER  -