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Survey of cathode deformations and further actions

F. Vercellati – INFN-PV

C. Montanari – CERN / INFN-PV

WA104@CERN weekly meeting, March 12, 2015

Cathode survey and present activitiesl We completed the mapping of cathode planarity on a grid of points with

300 mm spacing. Data are being transcribed and will be delivered soon.

l Please keep this presentation as a reference for the measurements.

l We are preparing to dismount the first cathode panel. The cables at the front (HV connection side) and the front “cross” have been dismounted. The first beam holding the first panel and hosting the HV connection cup has been removed. Level meters, position sensors and purity monitors have been removed.

l Following a safety review from Olga and Erwan and thanks to Dimiter, we are implementing a protection for the wires (a net) and a working plane all along the TPC.

l The first cathode panel will be dismounted between today and tomorrow.

l In the next three weeks we will remove the rivets that are holding the pierced sheet and plan for further actions.

Slide: 2WA104@CERN weekly meeting, March 12, 2015

Cathode panels

Slide: 3WA104@CERN weekly meeting, March 12, 2015

X

Y

145

85

Origin

Last

colu

mn o

f th

e g

rid

11

8

Cathode deformations

Slide: 4WA104@CERN weekly meeting, March 12, 2015

Panel 1 Panel 2

Panel 3 Panel 4

View of the TPC front side

Slide: 5WA104@CERN weekly meeting, March 12, 2015

First cathode panel

Beams of the “cross”

Net to protect the wires

Slide: 6WA104@CERN weekly meeting, March 12, 2015

Working plane (to be extended)

Slide: 7WA104@CERN weekly meeting, March 12, 2015