Low Radioactivity Techniques 2017

Session

Session 7

May 26, 2017, 10:20 AM

Seoul

Conveners

Session 7: Fabrication methods and surface contamination control

• Vitaly Kudryavtsev (University of Sheffield)

Session 7: Fabrication methods and surface contamination control

• Vitaly Kudryavtsev (University of Sheffield)

40. Development of a low alpha emitting μ-PIC for NEWAGE direction-sensitive dark matter search

Mr takashi Hashimoto (Kobe Univ.)

5/26/17, 10:20 AM

Oral

The NEWAGE detector is a gaseous micro-TPC using μ-PIC. We found the main background sources are alpha rays from the radioactive contaminations in the μ-PIC. So, low alpha emitting μ-PICs have been developed. The performance of these μ-PICs will be presented. We set up a surface alpha ray counter using micro TPC in Kamioka mine. We measured surface alpha ray emission rate of the μ-PIC. The...

14. Low background materials and fabrication techniques for Cables and connectors of the Majorana Demonstrator

Mr Matthew Busch (Duke University / TUNL)

5/26/17, 10:40 AM

Oral

The Majorana Collaboration is searching for the neutrinoless double-beta decay of the nucleus 76Ge. The Majorana Demonstrator is an array of germanium detectors deployed with the aim of implementing background reduction techniques suitable for a 1-tonne 76Ge-based search (LEGEND). These germanium detectors operate in an ultra-pure vacuum cryostat at 80K. One special challenge of an ultra-pure...

11. Radon Plate-out Measurements for Polyethylene and Copper at SNOLAB

Matthew Stein (Southern Methodist University)

5/26/17, 11:00 AM

Oral

Neutrons are a challenging background for dark matter direct detection experiments such as the Super Cryogenic Dark Matter Search (SuperCDMS), and can come from contamination within common shielding materials such as polyethylene and copper. We present measurements of the alpha-activity accumulation on surfaces due to exposure to the elevated level of radon present deep underground at SNOLAB....

43. Measurements of surface radioactivity by Alpha/Beta detection

Dr Pia Loaiza (LAL)

5/26/17, 11:20 AM

Oral

Surface contamination is an important background in many 2$\beta$0$\nu$ or dark matter searches. For example, gammas or betas can leak in the neutron recoil band if they sit on the surface of the bolometers like in Edelweiss or CDMS experiments. For 2$\beta$0$\nu$ experiments like CUORE, degraded surface alphas can get into the 2$\beta$0$\nu$ region and can not be distinguished from a ...

34. A review and outlook for the removal of radon-generated Po-210 surface contamination

Vincente Guiseppe (Univ. of South Carolina)

5/26/17, 1:30 PM

Oral

The next generation low-background detectors operating deep underground aim for unprecedented low levels of radioactive backgrounds. The deposition and presence of radon progeny on detector surfaces is an added source of energetic background events. In addition to limiting the detector material's radon exposure in order to reduce potential surface backgrounds, it is just as important to...

26. Removal of Rn-222 daughters from metal surfaces

Dr Krzysztof Pelczar (Jagiellonian University)

5/26/17, 1:50 PM

Oral

Surface contamination with long-lived daughters of Rn-222 is of great interest for experiments looking for rare events. These include the detection of low energy solar neutrinos, searches for neutrino-less double beta decay or searches or dark matter. Decays of Pb-210, Bi-210 and finally Po-210 may contribute significantly to the experiments’ background, especially when they appear close or...

36. On the DEAP-3600 in-situ resurfacing.

Mr Pietro Giampa (Queen's University)

5/26/17, 2:10 PM

Oral

The DEAP-3600 experiment is a single-phase detector that uses 3600 Kg of liquid argon to search for Dark Matter at SNOLAB, Sudbury, Canada, 6800 ft. underground. The projected sensitivity to the spin-independent WIMP-nucleon cross-section is 10$^{−46}$ cm$^{2}$ for a WIMP mass of 100 GeV. One of the primary sources backgrounds to the WIMP search are alpha decays occurring on the surface of...