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

[TRIUMF Seminars]

Date/Time: Thu 2013-01-10 at 14:00

Location:  Auditorium          

Speaker:   Matt Sternberg (University of Chicago and Argonne National Lab)

Title:     Recent Results on the Limit of Weak Tensor Currents from 8Li Beta-decay

Abstract: Precise measurements of the beta-neutrino angular correlation coefficient, ‘a’, provide information on the presence of possible exotic couplings in the weak interaction. In the beta-decay of 8Li to 8Be* and subsequent breakup into two alpha particles, the large Q value and the beta-alpha-neutrino correlation provide enhanced sensitivity to any potential tensor coupling. An initial measurement using the Beta-decay Paul Trap (BPT) at Argonne National Laboratory detected 2•10^4 beta-alpha-alpha coincidences, resulting in an upper limit of 1.5% on any tensor contribution. The BPT has since been upgraded with improved double-sided silicon strip detectors--including finer segmentation, thinner dead layers, and thicker active silicon--along with new plastic scintillators to kinematically over-determine the decay. Recent measurements using the improved system detected more than 2•10^5 beta-alpha-alphas and it is anticipated that this data will provide the first improved limits on weak tensor currents in over 50 years. I will discuss the current state of the analysis as well as future plans at the BPT.


Stimulants available 15 minutes before the talk.

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