The Summery of the NEMO 3 meeting

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The Summery of the NEMO 3 meeting
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The topic Discussed
1) Some problems in variation of the gain of the
counters and resoulution of the counters (for
PMTs). This can be taken in to account in the
analysis. But Roger Arnold belives that this
variation leads to a amall effect on the results
-gt So at the end everybody decided to ignore
this for the future publications! (Nd150 for
Example). 2) PM timing, Laser Time Correction
(LTC) and purpose of doing it! For laser runs for
each PM from trigger statement TDCkT(ADC)
TOF(laser light) TS const Where TDC is the
mean digital value of TDC in channels, K the TDC
channel constont (0.053 ns/ch). T(ADC) time
correction which depend on ADC content
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LTC PMiLaserRunj ?TDCT(ADC)? PMi LaserRunj -
?TDCT(ADC)? PMiReferenceRun
Which reference Run 1404!!
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The Conclusion for me!!!
Problem Add Status of PM There is no TS
1000 There is no T(ADC) 2000 There is no
LTC 1000000 Bad PM between two laser
runs 2000000
Kill event if it have the above condisions! As
this information is just avaible for good runs I
should not use run number with status!1 which I
showed the result on Jaca meeting.
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3) A discussion opened by Victor that electron
energy coming from Bi207 data (from the
calibration runs) has a higer peaks than the
simulated MC! And he predicted 5 uncertainty on
MC Simulation. This means I need to consider
this in my Bi207 activity measurement until
this problem is going to be fixed! 4) External
background (one of the main discussion topics and
still not sure!), can be estimated with two
methods. One is to look at eg-external channel
and one crossing electron Channel.
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Background model like for the low radon period
(best fit!!)
Despite Victors efford to underestand why the
external background is not described and lots of
simulations, could not find the source of the
missing backgrounds in low energy
crossing electrons!!!
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Again more or less the same is seen by G.Broudin.
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The second method is described by V.Vassiliev
(maybe less precise but answeres very well! The
external background is coming from g-sources from
outside the detector, so need to know spectrum of
g quanta near source Foil! He looks at 2electron
channel instead of eg-ext and crossing electron!
model spectrum 208Tl 228Ac 214BI 214Pb
40K 60Co He estimates the coefficients from eg
-ext channel analysis!
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How it mimic bb events?
External
double Compton
Compton Moller
pair production
dominant mode
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Results of the fit (see the note)
Internal wall
external wall, Phase II data
petal
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Still not sure which approach to use for the
purpose of Publications, but Vladimirs method
seem to be a solution Fro low external
background isotopes (Ca48 and Nd150..)

The discussion is going to be continued ..!
5)
Radon measurement inside the tracker! More
agreement In this part! Thy try to estimate the
background by looking at alpha-channel analysis
(e-alpha,ega,..). 11.5 uncertainty on the
measurement which can be improved with direct
calibration of Bi214 source!
List of the results that need to be extracted!
6)
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LIST OF RESULTS WHICH HAVE TO BE EXTRACTED FROM
THE DATA 1. 2?-decay to the ground
state. Finally we have to present a) 2e
spectrum b) single e spectrum c)
angular distribution. d) half-life value
(T1/2) with statistical and systematic errors.
2. 0?-decay. a) decay to the ground state
(lim T1/2 ltm?gt, RHC) b) decay to the 21
excited state (lim T1/2) c) decay to the 01
excited state (lim T1/2).
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3. 0??0-decay. As minimum 1) limit
(T1/2) on ordinary decay with n1. But it
is better to add limits on other possible schemes
with n 2, 3, 7. (See our NEMO-2 and NEMO-3
results Nucl.Phys. A 678 (2000) 341 Nucl. Phys.
A 781 (2007) 209.) 4. Finally we will extract
values or limits for NME(2?), ltm?gt, lt?gt, lt?gt,
ltgeegt, ?111 and so on. THEN IN EACH
INDIVIDUAL CASE THEY WILL DECIDE WHICH VALUES WE
HAVE TO PUBLISH AND IN WHICH WAY.