Wednesday October 2, 2013
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We will meet in TED 2561B on Wednesday October 2 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- Bubble Chamber progress at Argonne
2- Computer Center support: mailing list, group disk, wiki page, ...
3- Cost:
- Indirect General and Administrative (G&A) cost: 55.65% for both labor and procurement (Material and Shop) - Indirect Statutory and Fringe for labor: 57.15% - Final Bubble Chamber cost media:Bubble_FinalCost.pdf media:Bubble_FinalCost.pptx
4- Error Analysis:
- Analytical: Statistical, Absolute and Relative Systematic Errors media:Bubble_ErrAna.pdf media:Bubble_ErrAna.pptx - Monte Carlo Technique: Statistical, Absolute and Relative Systematic Errors media:Bubble_ErrAnaMC.pdf media:Bubble_ErrAnaMC.pptx
Notes from this meeting:
- Bubble Chamber:
- In the process of changing the buffer liquid from water to mercury (volume = 100 ml). Mercury will be in a sealed system that will allow for changing the active liquid without the need to remove or add mercury. - Mercury does not tolerate all other metals except for iron. However, CF iron gaskets will destroy the knife edges. Still looking for a solution. - The new design of the chamber will fit in the space between beamline and floor in the Injector (27 inches). - Adding acoustic signal readout to the chamber. - For 17O superheated target (needed to measure background), the ratio of 17O nuclei to 18O nuclei should be greater than 100. Note that the thresholds and cross sections for the reactions: 17O(γ,α)13C and 18O(γ,α)14C are very similar. - For 18O superheated target (needed to measure background), the ratio of 18O nuclei to 17O nuclei should be greater than 100.
- Cost:
- Will pass the Bubble Chamber cost estimate by Jefferson Lab Finance to get more realistic labor, procurement and shop costs
- Beamline Layout:
- We will not install a new BPM on the Spectrometer line since we have no way to know the absolute positions. The Bubble Chamber beamline will be equipped with two BPMs and two Super Harps that will be used to measure the beam energy. - We need to think very carefully if we need a vacuum pipe that connects the vacuum window to the Bubble Chamber. Would it add more protection to the vacuum window? Now, there is a risk of contaminating the beamline with oil. How to fit in the photon collimator? Any issues with alignment? Pumping on the vacuum pipe may introduce vibrations that may trigger the acoustic sensors.