EDM Assembly and Commissioning – or – How to Cut

Two Years from the ProjectP. Huffman and V. Cianciolo

Quick Answer• Decouple installation of the shields from installation of

the cryostat in the FNPB.– Previously assumed that bottom of shields needed to be

installed prior to cryostat.– If they can be slid under the cryostat along the beam axis then

the shields can be made and tested in parallel with cryostat commissioning.

• Cut off the project after the last subsystem (3He) is installed in the cryostat.– Pushes a significant amount of commissioning onto operations.– Requires modification of the CD4 requirements since as

previously constructed they required much of that commissioning to be complete.

– In our schedule the shields and coil package is at CIT at CD-4. We need to develop crisp arguments why this is a good idea.

Neutron lifetime of 300 sec, required polarization to be seen in SQUID w/ S/N=1 in 10 Hz BW.

1 in 10^11??

5 kV/cm for 1 cycle (?) minimum required to have an interesting measurement.

4 pe/MeV for an alpha source - Minimum required to have an interesting measurement.

100 µφ/sqrt(Hz) S/N =1 w/ 10 Hz BW

Demonstrate that central detector volume cools to 500 mK.

<dB/dx>/B0 < 10-5/cm over fiducial volume: required to make interesting measurement.

Operated with coil package in place.

Shielding factor 10-4: minimum spec

Is this “too many” CD4 Requirements?

• For FNPB we had 18. • I wanted to emphasize the value of ensuring that

these are achievable…

Why are the Shields/Coils at CIT when we Reach CD4? And is this OK?

• When we reach CD4 the shields will be fully tested w/o the cryostat.– We may want to install the shields around a mock-up of the cryostat to

ensure mechanical compatibility.– Are there other major problems we could miss by not testing the

shields and cryostat together?• If we keep them at CIT we could perform additional measurements

on the coil package. Necessary? Desired?• If we move them to ORNL they will need to a) stay in boxes, b) be

installed some place other than their final location, or c) installed in their final location.a) No obvious benefit accrues from this option. b) No obvious benefit accrues from this option and there is an increased

risk of damaging the shields.c) This option has some benefits, but will extend the project and

increases the risk of damaging the shields.

What Do We Save?• $701k Assembly + Commissioning• $591k Project Office

– Only ballpark – needs to have correct contingencies, inflation, etc. applied.

• Technicians may cost more:– 7 NCSU tech years on revised project.– NCSU: $110k/yr– ORNL: $215k/year– Three options (require Martin, Geoff, Glenn, Gene, Jehanne, Chris, etc.

to negotiate)• Techs all at ORNL

– Lose $735k of $1292k savings• Make 1 tech NCSU, stationed at ORNL.

– Lose $368k of $1292k savings.• Make 1 tech NCSU, stationed at ORNL, have ½ a tech paid by FNPB

operations (i.e., free), ½ a tech at ORNL rates.– Save an additional $8k