1 / 13

EDM B-Field Issues

EDM B-Field Issues. EDM B-field Specifications R&D Projects Hardware Requirements What’s available What’s needed. B. Filippone. n-EDM Specifications 3/28/03 pre-Proposal vs NSAC Sub-comm. 10 -3 homogeneity (@ B ~ 1mG) required over large volume and with large “penetrations”

dieter
Télécharger la présentation

EDM B-Field Issues

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. EDM B-Field Issues • EDM B-field Specifications • R&D Projects • Hardware Requirements • What’s available • What’s needed B. Filippone

  2. n-EDM Specifications3/28/03 pre-Proposal vs NSAC Sub-comm. • 10-3 homogeneity (@ B ~ 1mG) required over large volume and with large “penetrations” (Any change for dn < 10-28 e-cm?) • (1/B)dB/dt < 10-6/s via mag. shielding to minimize fluctuations and allow operation of SQUID sensors (Need 10x better shielding for dn < 10-28 e-cm)

  3. Cosq Magnet Superconducting Shield B-field and Shielding Plus external multilayer mu-metal shield (to reduce local fields) ~2.3 m

  4. Magnetic Shielding • EDM Apparatus at Low T (< 1 K) • Superconducting shield is innermost shield in 3/28/03 pre-proposal • But SC shield never used in previous EDM experiments • Trapped flux may vary randomly giving increased B-field noise • Anecdotal info [J. Eisenstein (CIT)] also not good • Standard Ferromagnetic shielding (mu-metal) performs poorly at low T • With m from 50,000 at 300K to < 10,000 at 4K

  5. Discussed last time several advanced materials • Cryoperm10 • (m from 25,000 at 300K to 75,000 at 4K) • Metglas • Amorphous metal • Very large un-annealed m (>200,000) • Very small magnetostriction • Small loss in m under mechanical stress

  6. R&D Efforts • Study & test low T behavior of promising ferromagnetic materials • Tests to 4K at CIT, to < 1K at UIUC • Build ~ ¼ scale prototypes • Including Superconducting shield, penetrations and Cosq coil

  7. R&D Hardware • 3-axis Hall Probe (at CIT) • Cryogenic Hall probe • Fluxgate magnetometer • LHe and Transfer line • Cryoperm & Metglas prototypes • Mu metal and/or 3-axis Helmholtz to limit environmental fields • 4K & 1K Dewar (at CIT & UIUC)

  8. ¼ scale prototype from Amuneal ~ 2k$

  9. Comes in 50mm x .02mm x 2,700,000mm Rolls have one at Caltech ~ 1k$

  10. Wide Mouth DewarBorrowed from Jim Eisenstein (CIT)

  11. 8 inch clear bore 20 cm

  12. Larger Bore Dewar also Available 20 cm 30 cm 200 cm

  13. R&D plans • M. Cheung (summer student), T. Ito, BWF • Order/assemble hardware 6-7/03 • 77K Ferromagnetic tests by 9/03 • 4K Ferromagnetic tests by 12/03 • 1K tests @ UIUC in spring 04

More Related