TPC alignment

Tome Anticic

Rudjer Boskovic Institute

Oct 2010

anticic@irb.hr 2/9

2009 x,y residuals before/after

With corrections (using millepede)

No corrections

X residuals

(cm)

Y residuals

(cm)

Z (cm)

anticic@irb.hr 3/9

2009 bx, by residuals before/after

With corrections (using millepede)

No corrections

bx (cm)

by (cm)bx, by improved

a little

anticic@irb.hr 4/9

2009 bx, by residuals before/after II

bx (cm)

VT1VT2MTL

bx (cm)

VT1VT2

Improvements more apparent when looking in more detail

With corrections (using millepede)

No corrections

anticic@irb.hr 5/9

Conclusion

Geometry corrected for 2009 (using 50000 events for run 8687)

For 2009 no need for global geometry parameter corrections ( positions and angles of TPCs), only the local ones (for ExB efects etc), as the given geometry is already very

good

GTPC not included in analysis

TPC millepede alignment correction setup up and available,and waiting for new material to be aligned!