TPC meeting, GSI, 2-3 June 2003 Børge Svane Nielsen, NBI 1

Status of laser systemStatus of laser system

TPC meeting, GSI, 2-3 June 2003Børge Svane Nielsen, Jørn Westergaard

Niels Bohr Institute

Work since January 2003 (PRR on 27 January 2003) Micro-mirror status Assembly of laser rods Optics and mechanics on end-plates

TPC meeting, GSI, 2-3 June 2003 Børge Svane Nielsen, NBI 2

Micromirror productionMicromirror production

97 bundles produced and delivered in February 2003, 60 accepted based on surface quality and angles 48 have been selected for the TPC

reflecting surfaces

brass cup

mechanical reference surface

Micromirror bundle

TPC meeting, GSI, 2-3 June 2003 Børge Svane Nielsen, NBI 3

Mirror reflectancesMirror reflectances

Preliminary accepted bundles (based on reflectance and image quality): 50-60 bundles out of 97 received

Amplitudes of profiles:

Micro-mirror reflection amplitude

0

50

100

150

200

250

1 51 101 151 201 251 301 351 401 451 501 551 601 651

Micro-mirror number

Ref

lect

ion

inte

nsi

ty

(arb

.un

its)

TPC meeting, GSI, 2-3 June 2003 Børge Svane Nielsen, NBI 4

Angles measurementsAngles measurementsPhi-Phi1 angle deviations from specs

-2.0

-1.0

0.0

1.0

2.0

1 51 101 151 201 251 301 351 401 451 501 551 601 651

Micro-mirror number

Ph

i dev

iati

on

s (d

egre

es)

Theta angle - 90 degrees

-3.0

-2.0

-1.0

0.0

1.0

2.0

3.0

1 51 101 151 201 251 301 351 401 451 501 551 601 651

Micro-mirror number

Th

eta

ang

le d

evia

tio

ns

(deg

rees

)

Mean = -0.04Sigma = 0.28

Mean = -0.28Sigma = 0.81

TPC meeting, GSI, 2-3 June 2003 Børge Svane Nielsen, NBI 5

Linear measurementsLinear measurements

L

Length deviation from specs

-2.0

-1.0

0.0

1.0

2.0

1 51 101 151 201 251 301 351 401 451 501 551 601 651

Micro-mirror number

Len

gth

dev

iati

on

(m

m)

Mean = 0.24 mmSigma = 0.50 mm

TPC meeting, GSI, 2-3 June 2003 Børge Svane Nielsen, NBI 6

Rod gluingRod gluing

1. Drill holes in short rods: in progress2. Mount mirror bundles in support rings: to be done at NBI, awaiting laser

3. Glue mirror support rings onto short rods at CERN. Test gluing done. Theta alignment guaranteed by jig +

machined surface

4. Glue short rods into full length rods at CERN. Phi alignment adjusted during gluing, using laser

5. Measurements on final rod possible in lab at CERN before installation.

Foreseen to be finished in September.

TPC meeting, GSI, 2-3 June 2003 Børge Svane Nielsen, NBI 7

Holes in laser rodsHoles in laser rodsMicromirror positions as seen by laser beam:

Near end-plates Near central electrode

TPC meeting, GSI, 2-3 June 2003 Børge Svane Nielsen, NBI 8

Test gluing at CERNTest gluing at CERN

TPC meeting, GSI, 2-3 June 2003 Børge Svane Nielsen, NBI 9

On-going activitiesOn-going activities Market survey of optical components for end-plates and laser hut completed: order about to be placed with Eksma for € 30,000

Funds secured for 2nd laser in 2004, ship directly to CERN

Design in progress on opto-mechanical supports on end-plates Gregory et al working on the details of the laser hut

Piezo-electric adjustment system from New Focus: network interface and one 3-axis adjuster in house for testing more 3-axis adjusters to be added

DCS: discussions towards a URD started: laser remote control: RS-232 3-axis adjusters control: Ethernet or RS-232 cameras: USB to PC downstairs

TPC meeting, GSI, 2-3 June 2003 Børge Svane Nielsen, NBI 10

Laser system principleLaser system principle