tpc meeting, nbi, 2-3 september 2002børge svane nielsen, nbi1 status of laser system tpc meeting,...
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TPC meeting, NBI, 2-3 September 2002 Børge Svane Nielsen, NBI 1
Status of laser systemStatus of laser system
TPC meeting, Copenhagen, 2-3 September 2002Børge Svane Nielsen, Jørn Westergaard
Niels Bohr Institute
Effect of laser on mylar foil Design details frozen since May Micro-mirror status Mirror support rings status Assembly of laser rods Optics and mechanics on end-plates
TPC meeting, NBI, 2-3 September 2002 Børge Svane Nielsen, NBI 2
Laser beams hitting mylar strips in TPC
Laser beams hitting mylar strips in TPC
mylar strips
TB: What is the effect on the mylar strips from the laser beams?
TPC meeting, NBI, 2-3 September 2002 Børge Svane Nielsen, NBI 3
Preliminary testsPreliminary tests
We use aluminized mylar strip received from CERN
Shoot on strip with laser beam reflected from a micromirror ( 1 mm)
Preliminary results from last week:
300-370 J/pulse 1 mm through-going hole after 15 minutes! 150-200 J/pulse small damage after 6 hours 100-150 J/pulse no visible damage after 6-7 hours
Design power is 20 J/pulse, well below the tested values.We believe that the damage is due to melting of the Al layer.
Plan more systematic tests over longer time, but hard to do longer than 1 week.
TPC meeting, NBI, 2-3 September 2002 Børge Svane Nielsen, NBI 4
Status of laser systemStatus of laser system
TPC meeting, Copenhagen, 2-3 September 2002Børge Svane Nielsen, Jørn Westergaard
Niels Bohr Institute
Effect of laser on mylar foil Design details frozen since May Micro-mirror status Mirror support rings status Assembly of laser rods Optics and mechanics on end-plates
TPC meeting, NBI, 2-3 September 2002 Børge Svane Nielsen, NBI 5
Rod numberingRod numbering
TPC meeting, NBI, 2-3 September 2002 Børge Svane Nielsen, NBI 6
Micromirror z positionsMicromirror z positions
TPC meeting, NBI, 2-3 September 2002 Børge Svane Nielsen, NBI 7
Muon arm side beam transport
Muon arm side beam transport
limited space between TPC and space frame move beam transport 10º from vertical plane adds 2 mirrors on shaft side + modifies beam transport on muon side
hope to attach 50 mm pipe on outside of TPC permanently
special prism
”knee” in beam transport on shaft side
”standard” prism
Muon side
Shaft side
TPC meeting, NBI, 2-3 September 2002 Børge Svane Nielsen, NBI 8
Micromirror productionMicromirror production
A.Ridiger, Moscow: all 60 bundles produced all angle measurements done report received, delivery imminent
micro-mirror bundle
brass cup
protection cap
TPC meeting, NBI, 2-3 September 2002 Børge Svane Nielsen, NBI 9
Micromirror measurementsMicromirror measurements
and angles of all micromirror faces measured by goniometer in Moscow
0.0014 (5 arc sec)
TPC meeting, NBI, 2-3 September 2002 Børge Svane Nielsen, NBI 10
Ideal laser tracks in TPCIdeal laser tracks in TPC
TPC meeting, NBI, 2-3 September 2002 Børge Svane Nielsen, NBI 11
angle measurements angle measurements
Mean = 0.111Sigma = 0.190
Mean = 0.033Sigma = 0.229
TPC meeting, NBI, 2-3 September 2002 Børge Svane Nielsen, NBI 12
angle measurements angle measurements
Ideal angle = 45º
Mean = -0.048Sigma = 0.073
TPC meeting, NBI, 2-3 September 2002 Børge Svane Nielsen, NBI 13
Linear measurementsLinear measurements
Top mirrors
Mean = 6.24 mmSigma = 0.27 mm
Mean = 4.75 mmSigma = 0.35 mm
Mean = 3.25 mmSigma = 0.35 mm
Middle mirrors
Bottom mirrors
L
TPC meeting, NBI, 2-3 September 2002 Børge Svane Nielsen, NBI 14
Laser rod with mirrorsLaser rod with mirrors
TPC meeting, NBI, 2-3 September 2002 Børge Svane Nielsen, NBI 15
Mirror support ringsMirror support rings
NBI workshop: 50 mirror support rings in production
Prototype produced at NBI
TPC meeting, NBI, 2-3 September 2002 Børge Svane Nielsen, NBI 16
Rod gluingRod gluing
Two stage gluing procedure at CERN:
1. Mirror support rings glued to short rods. Theta alignment guaranteed by jig
2. Full length rod glued from short rods. Phi alignment adjusted during gluing
3. Measurements on final rod possible before installation.
TPC meeting, NBI, 2-3 September 2002 Børge Svane Nielsen, NBI 17
Optics and mechanics on end-plates
Optics and mechanics on end-plates
Design in progress on opto-mechanical supports on end-plates
Prism holder:
Prototype to be constructed in NBI workshop soon
Laserbeam
Market survey on optical components for end-plates imminent