Boston Micromegas 4-Layer Test Chamber Plans and Progress Zhen Yan, - - PowerPoint PPT Presentation

boston micromegas 4 layer test chamber plans and progress
SMART_READER_LITE
LIVE PREVIEW

Boston Micromegas 4-Layer Test Chamber Plans and Progress Zhen Yan, - - PowerPoint PPT Presentation

Boston Micromegas 4-Layer Test Chamber Plans and Progress Zhen Yan, Boston University November 12, 2013 1 Boston University personnel Steve Ahlen, Professor Andrew Inglis, Engineering Physicist Zhen Yan, Physicist Mike


slide-1
SLIDE 1

Boston Micromegas 4-Layer Test Chamber – Plans and Progress

Zhen Yan, Boston University November 12, 2013

1

slide-2
SLIDE 2

Boston University personnel

  • Steve Ahlen, Professor
  • Andrew Inglis, Engineering Physicist
  • Zhen Yan, Physicist
  • Mike Kruskal, Graduate Student
  • Emma Rosenfeld, Undergraduate Student

2

slide-3
SLIDE 3

Boston 4-Layer Test Chamber

  • Collaboration of Boston University and Harvard University.
  • Four layers of Micromegas PCBs so that particle trajectories can be

measured and tracking resolution can be verified.

  • Built with solid, precision materials (± 40 mm) for precise alignment

(the detector construction technique is optimized for studies of MM PCB performance and precision, and for evaluating MM electronics, but is not suitable for production of chambers to be used in NSW) .

  • Active area = 1027 mm x 461 mm.
  • Project approved September 2013.
  • Chamber to be built at Boston University in Class 1000 cleanroom by

March 2014.

  • Chamber will be tested at BU and sent to Harvard by May 2014.
  • Harvard will test chamber with VMM2 electronics using cosmic ray

test stand that was set up to test BMC MDT chambers and electronics for Small Wheel.

3

slide-4
SLIDE 4

BMC Test Stand at Harvard with Mod-0 in 2001 Many problems with first generation MDT electronics were found and fixed

4

slide-5
SLIDE 5

BU supervised construction and testing of Small Wheel MDT Chambers at Harvard

5

slide-6
SLIDE 6

Design of one layer of MM chamber

6

slide-7
SLIDE 7

Micromegas PCB Construction of 4 boards begins at CERN this week

  • Designed by Andrew Inglis and Givi Sekhniaidze
  • Overall dimensions 1260 mm x 533 mm
  • Active area (black area shown below) 1027 mm x 461 mm
  • Cu/resistive strip pitch = 450 mm
  • Cu/resistive strip width = 300 mm
  • Pillars: diameter = 300 mm, spacing = 7.07 mm

7

slide-8
SLIDE 8

MM PCBs will be glued to machine ready aluminum blanks on granite table. PCB will extend over edge to allow space for

  • connectors. Top and side views below.

8

slide-9
SLIDE 9

Alignment Plan (details to be determined)

  • Horizontal PCB surfaces will be made parallel with

uniform separation distances by using shims, based on mechanical measurements on granite table.

  • Resistive strip positions will be measured relative to

aluminum blank edges from photographs with 40 Mpixel medium format camera (see slides below).

  • Measurements of horizontal positions of PCB support

blanks will be made with standard mechanical instruments on granite table of aluminum blank edges.

  • Data on horizontal positions will be used to determine

precision trajectories from MM DAQ data.

9

slide-10
SLIDE 10

Drift gap = 5 mm; bottom Al plate thickness = 12.7 mm; top 4 Al plate thicknesses = 6.3 mm

10

slide-11
SLIDE 11

Materials, frame stretcher, have been received

11

slide-12
SLIDE 12

12

slide-13
SLIDE 13

13

slide-14
SLIDE 14

BU Cleanroom

14

slide-15
SLIDE 15

New granite table for chamber construction

15

slide-16
SLIDE 16

BU Cleanroom environmental data

16

slide-17
SLIDE 17

Other MM activities at BU

  • Measure positions of resistive strips using 40

Megapixel Medium Format CCD camera (Pentax 645D with FA645 55mm f/2.8 lens).

  • Measure positions of copper strips with x-rays.
  • Study electrical discharges with transparent

chamber cover plate and single photon sensitive full frame 18 Megapixel CMOS camera (Canon EOS-1D X with EF 35mm f/1.4 lens).

17

slide-18
SLIDE 18

18

slide-19
SLIDE 19

Photograph of resistive strips; lens distortions are eliminated by taking photos of precision ruler (precision of strip measurements verified to be better than 20 mm over 250 mm).

19

slide-20
SLIDE 20

20

slide-21
SLIDE 21

21

slide-22
SLIDE 22

X-ray of MM; 100 keV; 43 cm x 35 cm; selection box shown was moved along vertical line of pixels; 100 microns/pixel

22

slide-23
SLIDE 23

Summary

  • BU Cleanroom was set up with University funding in 2012 in

anticipation of proposal for MM construction site in collaboration with Brandeis and Harvard.

  • US budget decisions and cuts have reduced scope of initial plan.
  • Approval and funding for this de-scoped project began September

2013.

  • BU will build 4-layer, 1 m x 0.46 m MM chamber, with precision

alignment that will be delivered to Harvard in May 2014 for cosmic ray and electronics testing.

  • BU will complete optical survey of resistive strips and x-ray survey
  • f copper strips on current BU MM PCB by January 2014.
  • BU will study electrical discharges with single-photon sensitive

camera to study cleanliness and assembly specifications for MM chambers (to be completed April 2014).

23