Search for Time- and Parity Reversal-Violating Nuclear Spin-Dependent Interactions in thallium fluoride

Search for Time- and Parity Reversal-Violating Nuclear Spin-Dependent Interactions in thallium fluoride
Dr. Olivier Grasdijk, Yale University
Olivier Grasdijk photo
Date and time: Fri, Sep 27, 2019 - 2:15pm
Location: LGRT 419B
Category: ACFI Seminar
Abstract:

Time (T)- and parity reversal (P)-violating interactions are sensitive probes of physics beyond the Standard Model. CeNTREX (Cold molecule Nuclear Time-Reversal Experiment) aims to search for nuclear spin-dependent P- and T-violating interactions, e.g. due to the nuclear Schiff Moment of 205Tl, in the molecule thallium fluoride (TlF). The choice for a molecule versus an atom is motivated by the much larger polarizability, leading to obervable energy shifts larger by a factor of ~104. The search for T- and P- violation in 205Tl is complementary to most other searches in atoms, molecules and neutrons. 

We will look for a T-,P-violating interaction by sending a cryogenic molecular beam of TlF through an interaction region where the direction of an electric field, relative to the nuclear spin, is alternately switched. This will generate a change in the nuclear spin precession frequency proportional to the Schiff moment. We project a significant improvement in sensitivity compared to the current state of the art. Instrumental in achieving this sensitivity is the use of optical cycling for efficient detection, rotational cooling, an electrostatic molecular lens, and a 3 meter long interaction region.