086/06/04 E. Auffray, PH-CMA

E. Auffray, CERN PH-CMA

Very preliminary results on new SIC crystals received 01/06/04

086/06/04 E. Auffray, PH-CMA

Introduction

We received : 20 endcaps crystals 10 barrel crystals type 6 with 1 face depolished

(lapped)

They have all followed the “routine” QC procedure

– Identification

– Visual Inspection

– Accoce2 measurements (exept 3D for 20 Endcaps crystals)

086/06/04 E. Auffray, PH-CMA

10 barrel crystals dimension

086/06/04 E. Auffray, PH-CMA

Lateral Dimension

AF

BF

CF

AR

BR

CR

086/06/04 E. Auffray, PH-CMA

length

086/06/04 E. Auffray, PH-CMA

Planearity

1 2

5 6

3 4

086/06/04 E. Auffray, PH-CMA

Right angle

1-3 1-6

2-3 2-6

086/06/04 E. Auffray, PH-CMA

Right angle

2-3 2-6

2-3 2-6

Barrel

Endcaps Jan 04

086/06/04 E. Auffray, PH-CMA

Transmissions

086/06/04 E. Auffray, PH-CMA

Longitudinal Transmission

360nm

420nm

620nm

10 barrel crystals

086/06/04 E. Auffray, PH-CMA

Longitudinal Transmission

360nm

420nm

620nm

20 Endcap crystals

086/06/04 E. Auffray, PH-CMA

Longitudinal TransmissionComparison with SIC data

360nm

420nm

620nm

086/06/04 E. Auffray, PH-CMA

Transmission @ 360nm

10 barrels05/04

20 Endcaps05/04

50 Endcaps01/04

086/06/04 E. Auffray, PH-CMA

Transmission @ 420nm

10 barrels05/04

20 Endcaps05/04

50 Endcaps01/04

086/06/04 E. Auffray, PH-CMA

Transmission @ 620nm

10 barrels05/04

20 Endcaps05/04

50 Endcaps01/04

086/06/04 E. Auffray, PH-CMA

slope

10 barrels05/04

20 Endcaps05/04

50 Endcaps01/04

086/06/04 E. Auffray, PH-CMA

dispersion

10 barrels05/04

20 Endcaps05/04

50 Endcaps01/04

086/06/04 E. Auffray, PH-CMA

Gradient

10 barrels05/04

20 Endcaps05/04

50 Endcaps01/04

086/06/04 E. Auffray, PH-CMA

LY for barrel(1 face depolished)

LY

FNUF

RNUF

086/06/04 E. Auffray, PH-CMA

Correlation with SIC data

086/06/04 E. Auffray, PH-CMA

Effect of the “depolishing”

086/06/04 E. Auffray, PH-CMA

Conclusions on recent Chinese crystals

Dimension– Geometry has been improved for barrel– We have to see the results for Endcaps

Longitudinal transmission:– Good correlation with SIC data at 360nm– @ 420nm & 620nm the correlation is worse due probably to a

different crystal orientation for measurements – Transmission for endcaps are similar to the previous batch– For the barrel, the transmission is lower (particularly @ 360nm)s

Dispersion of TTO :– For Endcaps it is the same than previous batch– For barrel the dispersion is better– Most of the crystals have been cut in the same direction

LY – Good correlation with SIC data (still 3pe/MeV difference)

LY Non uniformity– With 1 face lapped, FNUF of barrel crystals are slightly too

negatif , – a Ra of ~0.45-0.5m should be enough to have uniform crystals