Tracker Hardware Update Aron Fish 25/01/06 Aron Fish 25/01/06

Contents  Disassembly  Waveguide Mapping  Waveguide Check  Mirroring  Bulkhead Connector Alignment  Hardware Equipment  Disassembly  Waveguide Mapping  Waveguide Check  Mirroring  Bulkhead Connector Alignment  Hardware Equipment

Waveguide (Stays the same) D0 End (old) Bulkhead End(old)New Labels (for DO and Bulkhead ends) Comments D5D E1E101Boot is loose DO end- fibres exposed F22F102DO connector had no cover CC103Boot loose - not as bad as AA104 15B12 12 Existing & New Labels on Waveguides

Bulkhead (external)Bulkhead (internal)Comments 1055Bulkhead connector screwed in but not tight 1011Bulkhead connector screwed in tight 1022Bulkhead connector screwed in tight 1044Bulkhead connector screwed in but not tight 1033Bulkhead connector screwed in but not tight Disassembly continued…..

V W X V1 V12 W1 W12 X1 X12 Station Connector Numbering Stations A, B, C Viewed from waveguide end V W X C10 C1 C30 C21 C20 C11 V W X V1 V10 W1 W10 X1 X10 Station D (old)Station D (new version, so same format & direction as A, B & C ) UP RIGHT UP RIGHT UP

Station Connector PositionWaveguideD0 Connector X2,X3,X4,X5,X6,X7,X813 X9,X10,X11,X12,V1,V2,V342 V4,V5,V6,V7,V8,V9,V1077 Waveguide Mapping Station A X1, V11, V12 all unused station connectors positions

Station Connector PositionWaveguideD0 Connector W2,W3,W4,W5,W6,W7,W8118 W9,W10,W11,W12,X1,X2,X31512 X4,X5,X6,X7,X8,X9,X10211 X11,X12,V1,V2,V3,V4,V5514 V6,V7,V8,V9,V10,V11,V1286 Waveguide Mapping Station B W1 is the only unused station connector position

Station Connector PositionWaveguideD0 Connector W3,W4,W5,W6,W7,W8,W9101 W10,W11,W12,X1,X2,X3,X4134 X5,X6,X7,X8,X9,X10,X11149 Waveguide Mapping Station C W1, W2, X12 all unused station connectors positions

Station Connector PositionWaveguideD0 Connector W1,W2,W3,W4,W5,W W7,W8,W9,W10,X1,X X3,X4,X5,X6,X7,X83103 X9,X10,V1,V2,V3,V46102 V5,V6,V7,V8,V9,V Waveguide Mapping Station D

Waveguide Mapping Contin….  By injecting light using the filtered LED, I have also checked the light output from the D0 --> bulkhead --> station connector.  The dead channels have been noted and the mapping information from this has also been noted. This will be put together with my other mapping information to produce a final (correct) version of the fibre and waveguide mapping.  Also, there was no light loss notable by eye. This will need to be checked again quantitively, once the CCD camera set-up arrives.  By injecting light using the filtered LED, I have also checked the light output from the D0 --> bulkhead --> station connector.  The dead channels have been noted and the mapping information from this has also been noted. This will be put together with my other mapping information to produce a final (correct) version of the fibre and waveguide mapping.  Also, there was no light loss notable by eye. This will need to be checked again quantitively, once the CCD camera set-up arrives.

Mirroring  For a first look at the mirroring on the 4th station, we used a red LED to illuminate the scintillating fibres at the station connectors.  We found that light was coming through the mirrored ends, but not for all the fibres, I’d say roughly a 1/3 of them (which Roger had predicted) and from what I can remember, Malcolm and Hideyuki’s results show a uniform 30% loss over the 4th station.  Paul Kyberd also saw a similar amount of loss for the 3 old stations, which indicates that the mirroring isn’t solely causing the 30% loss of photons, but again this was only a first look by eye, so could be misleading.  We found that light across the planes was delineated by light being scattered out? (See picture on other.ppt.)  Also, we found more loss of light near the sharp edge of the station carbon fibre body. Geoff believes this could be from optical contact with the glue.  For a first look at the mirroring on the 4th station, we used a red LED to illuminate the scintillating fibres at the station connectors.  We found that light was coming through the mirrored ends, but not for all the fibres, I’d say roughly a 1/3 of them (which Roger had predicted) and from what I can remember, Malcolm and Hideyuki’s results show a uniform 30% loss over the 4th station.  Paul Kyberd also saw a similar amount of loss for the 3 old stations, which indicates that the mirroring isn’t solely causing the 30% loss of photons, but again this was only a first look by eye, so could be misleading.  We found that light across the planes was delineated by light being scattered out? (See picture on other.ppt.)  Also, we found more loss of light near the sharp edge of the station carbon fibre body. Geoff believes this could be from optical contact with the glue.

 Also whilst checking the mapping of the waveguides I came across one of the drilled holes in the bulkhead connector offset by a reasonably large amount.  This leads me to the question could the dowels for example on the bulkhead connectors (only used on 4th station) be slightly misaligned, leading to an offset of a roughly a few hundred microns? I.e. 30%? Could be a stupid question, as I’m sure it was measured precisely when the holes were drilled, but it might be worth reassessing, if possible?  Also whilst checking the mapping of the waveguides I came across one of the drilled holes in the bulkhead connector offset by a reasonably large amount.  This leads me to the question could the dowels for example on the bulkhead connectors (only used on 4th station) be slightly misaligned, leading to an offset of a roughly a few hundred microns? I.e. 30%? Could be a stupid question, as I’m sure it was measured precisely when the holes were drilled, but it might be worth reassessing, if possible? Again, sorry for bad picture but you can still clearly see the offset

 Paul Kyberd has suggested when the camera arrives “ we make a holder for the UV laser with a collimation hole at the front to allow a controllable amount of light through and that we hold this against the plane (or very close to), this solves the problem of imaging the light, which we need to do for the QA, but not for this measurement. Then we can take the camera and hold it up against the output of the fibres and make an integrated measurement, which again removes the need to worry about focus. It may be we need to do proper focusing to get a good enough measurement, but we should be able to do a good first look ”.  Geoff is currently designing a way of doing this, while Roger has already built a stand so that we can test each station carefully and without the station frame intact, so we have more room for maneuver.  Paul Kyberd has suggested when the camera arrives “ we make a holder for the UV laser with a collimation hole at the front to allow a controllable amount of light through and that we hold this against the plane (or very close to), this solves the problem of imaging the light, which we need to do for the QA, but not for this measurement. Then we can take the camera and hold it up against the output of the fibres and make an integrated measurement, which again removes the need to worry about focus. It may be we need to do proper focusing to get a good enough measurement, but we should be able to do a good first look ”.  Geoff is currently designing a way of doing this, while Roger has already built a stand so that we can test each station carefully and without the station frame intact, so we have more room for maneuver. Next Step….

Hardware equipment  CCD Cameras now ordered, expected at Imperial on Friday (27th Jan), worst case Monday (30th Jan).  Lenses ordered, 1-2 weeks expected for delivery, work on light loss can start without these, so least important.  Video capture card ordered and expected to arrive sometime early next week (31st Jan or 1st Feb).  Bill Cameron is currently organizing a PC for me to set-up in the tracker room at Imperial.  CCD Cameras now ordered, expected at Imperial on Friday (27th Jan), worst case Monday (30th Jan).  Lenses ordered, 1-2 weeks expected for delivery, work on light loss can start without these, so least important.  Video capture card ordered and expected to arrive sometime early next week (31st Jan or 1st Feb).  Bill Cameron is currently organizing a PC for me to set-up in the tracker room at Imperial.