Developing a Separated Oscillatory Fields Region for the CeNTREX Schiff Moment Measurement

The Cold molecule Nuclear Time-Reversal EXperiment (CeNTREX) will search for time-reversal and parity-violating interactions in the hadronic sector by measuring the Schiff moment of the $^{205}$Tl nucleus. A non-zero Schiff moment would provide insight into CP-violating physics beyond the Standard Model, and would help constrain $\theta_{\rm QCD}, quark chromo-electric dipole moments (cEDMs), and the proton EDM. CeNTREX uses a Ramsey-type separated oscillatory field technique (Interaction Region) to measure the spin precession frequency, with the Schiff moment contributing a small but detectable shift when the molecules are polarized. A large, uniform external electric field (~30 kV/cm) is generated using 3-meter-long glass electrodes machined with a Rogowski profile, coated with a conductive layer of water-based colloidal graphite and potassium silicate mixture. Passive magnetic shielding and shim coils reduce residual magnetic fields to below 10 µG. Magnetic Johnson noise is suppressed by the choice of coated glass electrodes inside a quartz vacuum chamber with a grounded conductive surface inside. This poster presents progress on implementing the interaction region, including electrode set-up and alignment, Johnson noise minimization, and systematic error mitigation strategies.