Difference between revisions of "Wednesday September 4, 2013"
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* Beamline Layout: | * Beamline Layout: | ||
- We will not install a new BPM on the Spectrometer line since we have to way to know the absolute beam position. The Bubble | - We will not install a new BPM on the Spectrometer line since we have to way to know the absolute beam position. The Bubble | ||
− | Chamber beamline will be equipped with two | + | Chamber beamline will be equipped with two BPMs and two Super Harps and 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 really | - We need to think very carefully if we need a vacuum pipe that connects the vacuum window to the Bubble chamber. Would it really | ||
add more protection to the vacuum window. How to fit i the photon collimator. Any issues with alignment. A turbo pump will keep the | add more protection to the vacuum window. How to fit i the photon collimator. Any issues with alignment. A turbo pump will keep the | ||
Line 44: | Line 44: | ||
* Error Analysis: | * Error Analysis: | ||
− | - | + | - Need to do more checks to make sure all makes sense. Puzzled by the finding that the errors at higher energies are larger than those at lower energies. We may want to try a PL unfolding for 7.9-8.5 MeV with a 0.2 MeV step and 8.3-8.5 MeV with 0.1 MeV step. |
+ | - Redo the error analysis using monte carlo techniques. |
Revision as of 14:34, 5 September 2013
We will meet in TED 2561B on Wednesday September 4 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:
media:Meeting_4September_2013.pdf media:Meeting_4September_2013.pptx
1- Bubble Chamber progress at Argonne
2- Superheated Liquids to be used in the experiment
3- Beamline Layout
4- Bubble Chamber cost estimate: procurement and labor
5- Error Analysis media:Bubble_ErrorAnalysis.pdf media:Bubble_ErrorAnalysis.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 closed system that will allow to change the superheated liquid without the need to work with mercury - The new design of the chamber will fit in the vertical clearance of 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 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 to way to know the absolute beam position. The Bubble Chamber beamline will be equipped with two BPMs and two Super Harps and 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 really add more protection to the vacuum window. How to fit i the photon collimator. Any issues with alignment. A turbo pump will keep the vacuum in this pipe. Would this pump affect the acoustic signal.
- Error Analysis:
- Need to do more checks to make sure all makes sense. Puzzled by the finding that the errors at higher energies are larger than those at lower energies. We may want to try a PL unfolding for 7.9-8.5 MeV with a 0.2 MeV step and 8.3-8.5 MeV with 0.1 MeV step. - Redo the error analysis using monte carlo techniques.