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BPC to CJC Alignment on 2006-2007 data with Positron Beam. M.Kapishin, V.Palichik JINR, Dubna June 25, 2007. Selection Conditions (1). HAT Selection: 2 < Q 2 < 100 GeV 2 12 < E SPACAL < 35 GeV 40 < E – p z < 80 GeV | Z vertex | < 28 cm.
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BPC to CJC Alignment on 2006-2007 data with Positron Beam M.Kapishin, V.Palichik JINR, Dubna June 25, 2007
Selection Conditions (1) HAT Selection: 2 < Q2 < 100 GeV2 12 < ESPACAL< 35 GeV 40 < E – pz < 80 GeV | Zvertex | < 28 cm Else we require sigma(Zvertex) < 2 cm
Selection Conditions (2) Spacal Cluster conditions: cluster radius < 4 cm Spacal – BPC and Spacal – CJC distance on Z(Spacal) less than 6 cm DTRA CJC track: momentum p > Pt > 0.4 GeV N(CJC hits) > 13 10 GeV, Ep = 920 GeV 9 GeV, Ep = 460 GeV
Selection Conditions (3), SW (BST- Vertex ) – distance < 0.5 cm on Z vertex (BST- Spacal ) – distance < 3 cm on Z spacal SW: h1oo 3.0.12 for 2006 data h1oo 3.0.13 for 2007 data
dPhi(BPC-CJC) shift = P1 – mean value of Gaussian
dXY(BPC-CJC) mean values of Gauss < ~ 0.1 mm
dTheta & dZ (BPC-CJC) dZ mean values of Gauss < 1 mm after BPC moving out from vertex by 2.5 – 3 mm
dTheta(BPC-CJC) vs Phi fit by P0 + P1 sin(Phi +P2 )* *) see D.Derkach & J.Kretzschmar, WLAN Meet. 23.IV.07
Tuned dTheta(BPC-CJC) vs Phi After lower&upper BPC shifts on dX = ZBPC P1sinP2 < ~ 1 mm dY = ZBPC P1 cos P2 < ~ 1 mm P0 = ~ 0 dZ = 0.0
dZ(BPC-BST) 0 mm shift for y > 0 6 mm shift for y < 0
dZspacal on BST-tracks 4 mm shift 5 mm shift
dZ(SPACAL-CJC) 3 mm shift for y < 0 -2 mm shift for y > 0
Conclusions BPC alignment of 2 steps: • minimize dPhi, dX, dY, dZ (BPC-CJC) • dTheta(BPC-CJC) vs Phi distributions are fitted by P0 + P1 sin(Phi +P2 ) for lower/upper BPC parts separately max dTheta(BPC-CJC) deviations vs Phi are in 0.5 mrad limits