Primary Vertex Reconstruction:results on first collisions data

Runs: 104030, 104044 (ITS only) 104065, 104070 (all detectors)

Trigger configuration: DSMBC 0SMB 0BPC DSMBB 0SMB 0BPA 0BPC DSMBA 0SMB 0BPA

Padova, 09/11/09 Corso di dottorato XXIV ciclo Davide CaffarriCERN, 07/12/09 First Physics Meeting

Davide Caffarri – Andrea Dainese INFN Padova.

Mean vtx VS tstamp

Padova, 09/11/09 Corso di dottorato XXIV ciclo Davide CaffarriCERN, 07/12/09 First Physics Meeting Davide Caffarri – Andrea Dainese 1

Run 104030 (the first one) seems to have different mean for x and z but…

Run 104030

Padova, 09/11/09 Corso di dottorato XXIV ciclo Davide CaffarriCERN, 07/12/09 First Physics Meeting Davide Caffarri – Andrea Dainese 2

Low number of entries and constraining the fit:

Mean -1.08 cm Mean -3.46 cmRMS 8.20 cm Sigma 3.44 cm

SPD vertex

Padova, 09/11/09 Corso di dottorato XXIV ciclo Davide CaffarriCERN, 07/12/09 First Physics Meeting Davide Caffarri – Andrea Dainese 3

X: mean - 724 µm sigma 474 µm

Z: mean - 3.2 cm sigma 3.7 cm

Y: mean + 0.16 cm sigma 500 µm

Tracks vertex

Padova, 09/11/09 Corso di dottorato XXIV ciclo Davide CaffarriCERN, 07/12/09 First Physics Meeting Davide Caffarri – Andrea Dainese 4

X: mean - 740 µm sigma 312 µm

Z: mean - 3.2 cm sigma 3.5 cm

Y: mean + 0.16 cm sigma 332 µm

TPC vertex

Padova, 09/11/09 Corso di dottorato XXIV ciclo Davide CaffarriCERN, 07/12/09 First Physics Meeting Davide Caffarri – Andrea Dainese 5

X: mean - 0.11 cm sigma 0.39 cm

Z: mean - 3.9 cm sigma 3.6 cm

Y: mean - 0.04 cm sigma 0.38 cm

Tracks VS SPD vertex

Padova, 09/11/09 Corso di dottorato XXIV ciclo Davide CaffarriCERN, 07/12/09 First Physics Meeting Davide Caffarri – Andrea Dainese 6

TPC VS SPD vertex

Padova, 09/11/09 Corso di dottorato XXIV ciclo Davide CaffarriCERN, 07/12/09 First Physics Meeting Davide Caffarri – Andrea Dainese 7

Contributors

Padova, 09/11/09 Corso di dottorato XXIV ciclo Davide CaffarriCERN, 07/12/09 First Physics Meeting Davide Caffarri – Andrea Dainese 8

SPD multiplicity ITS tracks with nclust>4

TPC tracksTPC track with Nclus > 0 pointing at the beam pipe

Vertex mean VS multiplicity

Padova, 09/11/09 Corso di dottorato XXIV ciclo Davide CaffarriCERN, 07/12/09 First Physics Meeting Davide Caffarri – Andrea Dainese 9

Vertex RMS VS multiplicity

Padova, 09/11/09 Corso di dottorato XXIV ciclo Davide CaffarriCERN, 07/12/09 First Physics Meeting Davide Caffarri – Andrea Dainese 10

Vertex efficiency VS multiplicity

Padova, 09/11/09 Corso di dottorato XXIV ciclo Davide CaffarriCERN, 07/12/09 First Physics Meeting Davide Caffarri – Andrea Dainese 11

Black: Z vertexRed: 3D vertex

Beam spot: Data and MC (I)

Padova, 09/11/09 Corso di dottorato XXIV ciclo Davide CaffarriCERN, 07/12/09 First Physics Meeting Davide Caffarri – Andrea Dainese 12

DATA LHC09d7

Beam spot: Data and MC (II)

Padova, 09/11/09 Corso di dottorato XXIV ciclo Davide CaffarriCERN, 07/12/09 First Physics Meeting Davide Caffarri – Andrea Dainese 13

DATA LHC09d7

Runs 104157 104160 (all detectors)

DINT1B 0BPA 0BPC l0fINT1DINT1C 0BPC *0BPA l0fINT1DINT1A 0BPA *0BPC l0fINT1

DBEAMB 0BPA 0BPC

Padova, 09/11/09 Corso di dottorato XXIV ciclo Davide CaffarriCERN, 07/12/09 First Physics Meeting Davide Caffarri – Andrea Dainese 14

Vertex mean VS tstamp

Padova, 09/11/09 Corso di dottorato XXIV ciclo Davide CaffarriCERN, 07/12/09 First Physics Meeting Davide Caffarri – Andrea Dainese 15

SPD vertex

Padova, 09/11/09 Corso di dottorato XXIV ciclo Davide CaffarriCERN, 07/12/09 First Physics Meeting Davide Caffarri – Andrea Dainese 16

X: Mean -780µm Sigma 460µm

Y: Mean +0.16 cm Sigma 480 µm

Z: Mean -3.3 cm Sigma 3.85 cm