Diapositive 1

KIN2 q=19.30 deuteriumtmin=-0.123 GeV2 q=2.78 GeV Pd=.352 GevInner calo 10x9 blockR=13.5 cm qg=8tmin=-0.33 GeV2 q=2.72 GeV Pd=.579 GevThe ProblemHow to detect the maximum of recoil deutons with reasonable silicon detectorWithout interfere with the accepted experimentPYBReasonnable silicona+/- 40 angular range ===> close of the Target as possibleMove the beam it is possible let said 1cm Detector close to 1cm from the target 2 cmSilicon detector dimension +/- 2xtan(40)/sin(18)=+/-5.42cm

which is limit of reasonable 20This insure that all the dvcs events produced in the target and with -tmin MeV 3Stop after Si

DE3MeV 10 times bigger that in the Compton PolarimeterPYB2 cm16x(5.5x50 mm2) strips32 stripsSilicon strips: 1mm100 mmPYBARSARSCharge amplifier. + derivation

Using ARS allow:Times coincidence ~ 1-2 nsDE analyzeVacuum feed-through

Like this of the polarimeter ComptonOnly the charge amplifier require a new studyPYBProton from the electro-desintegration of the deuton e+De+n+pAre the two dominant backgrounds Moller electronsThe proton field was computed by Pavel :

PYB15 cm LH2 I=10mA32 stripes : 5,5 x100 mm2 at 2 cm from the beam

PYBBut some stop in the deuterium Tp< 21 MeV2 cmTan(a)=d/l=2/16 a=7.12Electron Backgroung :The forward part of the silicon must have difficulties. If it the case 1,2 or n strips can be forgottenThe best will be to use a shorter target 5 or 4 cm a= 18o

PYBBut that will implied to increase beam intensity to 20 A and this intensity require the use of the raster !!!!!!Possible Improvement20 o Target f=20 mmAn other setup18oX0D=8cm

But an any case the absorption in the LH2 will conduct at the same range in t and fMy feeling:It is technically doable* for KIN2It will be better to used a 4 or 5 cm target !! The range in t and f is limited . In this range a cross section can be extract In this range the B-H is dominantLe jeu en vaut il la chandelle ?Knowing that this technique will be and more difficult to be applied at the 12 GeV when Q2 and t will increase. mechanical support of the silicon vacuum feed through position of target versus beam Preamplifier *PYB