[Triumf-seminars] TRIUMF Colloquium today at 14:00

[TRIUMF Seminars]

Date/Time: Thu 2021-11-04 at 14:00

Location:  Remote              

Speaker:   Stephan Friedrich (Lawrence Livermore National Laboratory)

Title:     High-Resolution Superconducting Tunnel Junction Radiation Detectors for Nuclear Science

Abstract: Cryogenic radiation detectors with operating temperatures below 0.1 K have been developed over the last decades because they offer an order of magnitude higher energy resolution than semiconducting Si and Ge detectors. Among these low-temperature detectors, superconducting tunnel junction (STJ) detectors stand out because they can be operated at relatively high rates of several 1000 counts/s per pixel. 

STJ consist of two superconducting electrodes separated by a thin insulating tunnel barrier. Absorption of radiation excites charges above the superconducting energy gap, and the resulting increase in tunneling current provides a direct measure of the deposited energy. Since the superconducting energy gap is only ~1 meV, STJs offer an energy resolution of a few eV FWHM for energies below 1 keV. The combination of high resolution, high speed and lack of a surface dead layer makes STJ well-suited to study ultra-low energy transitions or nuclear recoils. 

This talk will discuss design, operation and performance of STJ detectors in nuclear applications. One recent experiment is the search for sterile neutrinos in precision measurements of the decay of Be-7  that is implanted into STJ detectors. This experiment currently provides the most stringent limits on the existence of sterile neutrinos in the mass range form ~100 to ~800 keV, and upgrades to STJ detector arrays and increased Be-7 doses can further increase the sensitivity. The talk will also discuss possible other types of experiment that could be done with STJs in collaboration with TRIUMF.
--------------
https://ubc.zoom.us/j/69604219530?pwd=SWV0QVp1cGQ3OXlpOUNqa1hTOHY3Zz09 
Meeting ID: 696 0421 9530 
Passcode: 465904


Remote

______________________________

General TRIUMF seminar information available at http://www.triumf.ca/home/upcoming-events/about-seminars-lectures