Friday, March 5 1999
1:30 CDT
Minutes of MUCOLL Meeting
1) A0 Status: by Norbert Holtkamp
Norbert give un updated on the status of the rf cavities, this week
there were running at 10 MV and they hope to run next week with higher
power. Also they will inspect the foild, so far by visual inspection
the foild has changed color and has 2 dark spots. They will examine
the foild next week by replacing the foild. They will try to do a
radiation measurement on the foild in order to estimate the dark
current. The foild is about 16 mm in diameter and the plan is to go to
thinner foilds. During March 18-19 will be a meeting at FermiLab at
noon time in the 11th floor to discuss the results on berilum foilds,
results from the industry, on high power rf cavities and also a techinical
review committee will meet to decide how to spend the money for this
fiscal year.
2)Simulation meeting summary + Solenoid design preparation
status: by Paul Lebrun
Paul talk about the progress on the last Li-Lens cooling stage. A
discussion presented by Panagiotis Spentzouris on his DPGeant simulation,
with contribution from Valery Balbekov. The simulation found that two
stage of this type of cooling channel have been implemented in
DPGeant, the first stage, where the emittance is relatively large and the
last-1 stage (#13), which accepts a beam with normalized transverse
emittance of 670 mm mRad. This stage cools relatively less than the first
one, with higher loss: one achieves a final transverse emittance of
390 mm. mRad, with a 10% particle and a substantial longitdinal reheating
(wedges/bent solenoids are not included in DPGeant).
They were puzzled by the asymmetry in X and Y in the transverse emttiance
after going through the first matching lens, and a loss trough the large
jump in transverse, which signal a matching problem. Panagiotis will
resolve the first issue, the second one is unfortunately more difficult to
resolve, but they will meet on Monday to discuss a solution.
3)Tracking update: by Steve Kahn
Steve present a series of 4 tranparencies with plots showing the work he
is doing. His main gold is to determine the center of the ellipse for
a particle in a specific fringe field. He conclude that he can pin-point
the center of a track no better than .05 which is a factor of 2 to 4 off
with respect what is on the baseline design. At this point his calculation
doesn't include a difusion model. His next step will be to include such
a difusion model which he believe will make his calculation worst.
4)Wedge simulation update: by Rick Fernow
Rick did have a phone meeting with Steve? where they discuss an analitical
model for the solenoid. work his on progress.
Also he investigated how the emmittance grow? For this simulation he
modify ICOOL and first he check if he could reproduce B. Palmer file.
With low statistic data he found that the 3rd momentum was off by a factor
of two, but the problem went away with high statistics. Than he study
3 different cases and calcualted the growm of the 6D-emmittance.
1st Case:
High Stat. with bend solenoid ===> grow ~ 19%
2nd Case:
High Stat. with smaller transverse emmitt. ===> grow ~ 10%
3rd Case:
High Stat. with smaller longitudinal emmitt. ==> grow ~ 41%
But the time distribution in all 3 cases was distorded????
5)Muon bunched beam design status: by Dave Neuffer
Dave gave un updated on the compromises one have to accept by
constructing the muon beam in a cheaper manner.
First he consider two solenoids, the first at 5Tesla and the second
at 0.3Tesla. This imply that the acceptance will be 1/5 of the baseline.
Considering an adiabatic transition between solenoid will imply
a transition cavity of ~12.5 meters (approx.). Assuming a 20 meter
tunel for pion decay than the estimated intensity is
N/Nref = (1/5)2 x 1/10 x 1/10 x 1/4 =~ 10E-4
so therefore
N/Nref ~ 10E_5+1 mu/pi
compared with the baseline number of ~10E-1 mu/pi. But we could
improved the intensity by replacing the 0.3Tesla solenoid by a
couple of quadrupoles, this give an intensity of ~ 10E-4+1 mu/pi.
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