Wednesday February 12, 2014

We will meet in TL 2236 on Wednesday February 12 at 3:00 pm EST.

For those calling in we'll use the ReadyTalk audio conference system.

1. Dial Toll-Free Number: 866-740-1260 (U.S. & Canada)
2. Enter 7-digit access code 4402297, followed by “#”

Agenda:

1- New "5 MeV" Dipole update and shielding of Earth's magnetic field

2- Bubble Chamber progress at Argonne

3- January 12, 2014: achieved p=9.1 MeV/c or K.E.=8.6 MeV for one hour. Still, suffered from trips due to wave guide vacuum faults; may improve with more processing.

4- Issues raised during Accelerator Seminar on Jan 23, 2014:

- To better control bubble chamber deadtime, do we want to stop the beam when the bubble chamber is not ready for next-event?
That is, beam is on only when chamber is in superheat at the operational pressure. We can do that by blocking the laser path.
This can be done using the laser shutter system. The Bubble Chamber needs to provide a TTL signal to close the shutter. 
Then we can set a hold time of 10 s (or the time it takes to quench the bubble, superheat, and stabilize pressure) before opening
the shutter again. Closing and opening the shutter is very fast (<< 1 ms). Our laser shutter system is a combination of a Pockels
Cell backed by a mechanical shutter.
- Is there a nuclear reaction that would help us with the energy measurement?
- Can we present a theoretical calculation that shows the impact of JLab projected data on the the knowledge of S(300)?

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Notes from this meeting:

• New Dipole Magnet: