1. Michelle Espy email: espy@lanl.gov SQUID NMR Signal Outline Overview of SQUIDs in EDM: present thinking - experimental design ideas - expected signal, SQUIDs Update on SQUID NMR/MRI progress Obstacles and Issues 15 month plan - Final Design - Noise tests - NMR tests on polarized 3He - High voltage tests

2. Michelle Espy email: espy@lanl.gov Overview of SQUIDs in EDM: present thinking Experimental Design Ideas (big coils vs. gradiometers) Expected signal in 40x4 cm 2 coil 13.5 m  0 – coupling to SQUID ~1% for ~ 10 -4  0. SNR ~10 Expected signal in one gradiometer 10 -19 Wb, limit 2x10 -19 Wb SNR ~ 1/3 : Definitely Need Array

3. Michelle Espy email: espy@lanl.gov Overview of SQUIDs in EDM: present thinking Expected Signal, SQUIDs - Clearly signal larger for big coil - Vibration - Gradiometer advantages - Array of gradiometers - (12x12 with 36mm baseline) - Gradiometers AND big coils, “big” gradiometer? - Modeling Requirements (Chen-Yu) - Multiple SQUIDs? Coil position? Other designs, 48x48 – make grads wider?

4. Michelle Espy email: espy@lanl.gov - Measurements through/in presence of metal - Electronics for helping SQUIDs survive pulse, pulse sequences, cryoswitch already exists - Systems/hardware in place for tests - Understanding of NMR issues (transients, eddy currents etc.) Update on SQUID NMR/MRI progress Simultaneous measurements of biomagnetic signals and anatomy B 0 = 60 G, B m = 5.5μT Volegov, et al., Mag. Resn. Med., 52, 467 (2004)

5. Michelle Espy email: espy@lanl.gov 7-channel ULF-MRI reconstructed using SENSE (sensitivity encoding) approach Distortions due primarily to B p inhomogeneities T2* Contrast Image at 12  T (First ever T2* contrast image at  T fields) Kraus, et al., Human Brain Mapping (2005) Density Contrast image of Human Hand Zotev, et al., 4EG08 ASC (2006) Update on SQUID NMR/MRI progress

6. Michelle Espy email: espy@lanl.gov Remaining Obstacles and Issues - Vibration noise - Leakage current from HV electrodes - Johnson noise – mu metal inside superconducting shield, electrode material, sc shield material - Eddy currents - Other noise sources - Feed-throughs - Andrei/Steve discussion about RF shielding

7. Michelle Espy email: espy@lanl.gov 15 month plan What needs to be done/ what we can offer: Modeling, final design of SQUIDs SQUID/pick-up testing Noise testing (Johnson noise of materials - easy at 4K, can be moved into dilution refrigerator) NMR tests on 3He with SQUIDs HV Test with SQUIDs NMR signal extraction (experience with ULF-NMR, multiple component analysis, NIH grant)

8. Michelle Espy email: espy@lanl.gov 15 month plan