Tracker Subsystem 1

GLAST LAT Project FM-B PSR, 10 Feb, 2005

GLAST LAT TrackerGLAST LAT Tracker

Tower-B Pre-Ship ReviewTower-B Pre-Ship Review

Luca Latronico

INFN-Pisa

luca.latronico@pi.infn.it

Tracker Subsystem 2

GLAST LAT Project FM-B PSR, 10 Feb, 2005

Tower B Assembly and test highlightsTower B Assembly and test highlights

• 1/3-1/11 2005 (INFN-Pisa) : – assembly (tray stack, cables,

sidewalls, alignment, turn-over)

– test (CPT)

• 1/17-2/5 2005 (Alenia-Roma) : – VIB test (1/17-18)

– New TVAC chamber setup (see NCR/FM/INFN/PI-379)

– TVAC test (1/29-2/5)

• 2/8 2005 (INFN-Pisa) : – Alignment verification

• 2/10 2005: – Through customs in Roma airport

• Full EIDP details at: – http://glast.pi.infn.it

– Quality Assurance page

– EIDP links

Tracker Subsystem 3

GLAST LAT Project FM-B PSR, 10 Feb, 2005

Tower Alignment dataTower Alignment data

Tower Alignment CMM Data Processing Tools

ReportTower Inverted After TOF and Solithane appl. After Env Tests

Tower Half

WidthStatus Max

Tower Half

WidthStatus Max

Tower Half

WidthStatus Max

Nominal N/A 185.875 Nominal N/A 185.875 Nominal N/A 185.875Max N/A 186.25 Max N/A 186.250 Max N/A 186.250+X passed 185.989 +X passed 186.009 +X passed 186.000+Y passed 185.998 +Y passed 186.012 +Y passed 186.020-X passed -186.081 -X passed -186.106 -X passed -186.094-Y passed -186.040 -Y passed -186.007 -Y passed -186.004

Tower Full

WidthStatus Max

Tower Full

WidthStatus Max

Tower Full

WidthStatus Max

Nominal N/A 371.750 Nominal N/A 371.750 Nominal N/A 371.750Max N/A 372.50 Max N/A 372.50 Max N/A 372.50X passed 372.070 X passed 372.115 X passed 372.094Y passed 372.038 Y passed 372.020 Y passed 372.024

Washer Plane

Status Max

Nominal N/A 186.530Max N/A 186.750+X passed 186.641+Y passed 186.457-X passed -186.531-Y passed -186.495

Tower Full

WidthStatus Max

Nominal N/A 373.060Max N/A 373.500X passed 373.172Y passed 372.952

Flexure Cone

Status Theta Phi Gamma ZRadial Offset

FCS X Offset

FCS Y Offset

Alpha Beta

Nominal N/A 0.000 0.000 0.000 -37.420 0.000 0.000 0.000 0 0Tol Corner

N/A +/- 0.404 +/- 0.483 N/D -37.67 0.87 N/D -0.69 N/A N/A

Tol Side N/A N/D N/D N/D -37.67 0.87 N/D -0.35 N/A N/A0 passed 0.016 -0.087 0 -37.298 0.094 -0.026 0.091 10 -1591 passed 0.016 -0.087 0 0 0.109 -0.028 0.105 11 -1592 passed 0.041 -0.083 0.129 -37.27 0.119 0.045 0.111 12 1643 passed 0.01 -0.12 0 -37.331 0.089 -0.038 0.08 9 -1504 passed 0.01 -0.12 0 0 0.057 -0.04 0.041 6 -1325 passed 0.009 -0.137 0.129 -37.464 0.102 -0.029 -0.098 11 -116 passed 0.019 -0.041 0 -37.51 0.201 -0.176 -0.096 21 -507 passed 0.019 -0.041 0 0 0.195 -0.179 -0.078 21 -558 passed 0.004 -0.169 0.129 -37.438 0.089 0.058 -0.066 9 469 passed 0.008 0.035 0 -37.469 0.066 -0.035 -0.057 7 -2810 passed 0.008 0.035 0 0 0.036 -0.029 -0.021 3 -5211 passed 0.004 -0.183 0.129 -37.251 0.087 0.047 0.073 9 151

Before Vibe Test

After Vibe Test

All measurements within stay-clear and in spec before and after ENV tests

Tracker Subsystem 4

GLAST LAT Project FM-B PSR, 10 Feb, 2005

TOWER CG & MASSTOWER CG & MASS

298.695

TOWER Total Mass (g) 32424.80 ESTIMATED (Solithane, adhesive, tape, glues not included)

TOWER Total Mass (g) 32640.00 MEASURED (weighted)

4360.002955.00

TOWER+BP+CHP Mass (g) 39739.80 ESTIMATED (Solithane, adhesive, tape, glues not included)

241.334 ESTIMATED (Solithane, adhesive, tape, glues not included)

TOWER+BP+CHP Mass (g) 39955.00 ESTIMATED WITH MEASURED TWR TOTAL MASS

241.643 ESTIMATED WITH MEASURED TWR TOTAL MASS

TWR+BP+CHP CG from Flexures

TWR+BP+CHP CG from Flexures

Tower CG from Flexures

Base Plate (g)Cables Holding Plate (g)

Conclusions

Tower well aligned and inside stayclear

Stable after Env. Test

Mass and CG near estimated values (when used real masses)

Tracker Subsystem 5

GLAST LAT Project FM-B PSR, 10 Feb, 2005

Assembly and components detailsAssembly and components details

Relevant issues and related NCRs:– INFN/PI-220 (tray Bottom 006)

• M4X6 instead of M4x8• Proposed disposition is use as is and close

– INFN/PI-362 (Tower B)• Critical insulation of termination resistor on cable 7• SLAC will provide all cables with Kapton to protect

resistors• Proposed disposition is use as is and close

– INFN/PI-371 (Tower B)• Critical insulation between tower cables and fixing

clips• Kapton tape was used• Proposed dispositions are

– SLAC will provide all cables with kapton on all termination resistors

– use as is and close

– INFN/PI-349 (tray heavy 037)• GTFE21 back side instabilities• Found to be due to bad termination resistor

(100Ohm) on test cable• Proposed disposition is use as is and close

– INFN/PI-383 (Tower B)• Complete CPT not performed• Proposed dispositions are

– use as is and close– Consider removing test from flow-chart and rely on final

test after TVAC

Tracker Subsystem 6

GLAST LAT Project FM-B PSR, 10 Feb, 2005

Environmental tests highlightsEnvironmental tests highlights

• VIB test– No new channel loss

– No change in alignment

• TVAC test– New chamber setup

– Vacuum level slightly below spec (NCR-379-closed)

– Charge to Alenia to investigate chamber capabilities

1.E-06

1.E-05

1.E-04

1.E-03

29/01/20050.00.00

30/01/20050.00.00

31/01/20050.00.00

01/02/20050.00.00

02/02/20050.00.00

03/02/20050.00.00

04/02/20050.00.00

05/02/20050.00.00

06/02/20050.00.00

07/02/20050.00.00

Date

Pre

ssu

re(t

orr

)

Pressure(torr)

Tracker Subsystem 7

GLAST LAT Project FM-B PSR, 10 Feb, 2005

Disconnected channels in different runs

0

20

40

60

80

100

120

140

160N

um

ber

of

dis

con

nec

ted

ch

ans

Total

Total - (Y12 & X7)

Y12 (MID 043 Front)

X7 (MID 023 Front)

• total disconnected channels < 0.25%• ~50% of disconnected channels in 2 layers (Y12, X7):

– X7 with large oscillations vs temperature– Y12 responsible for overall channel loss– all other layers were very stable

Tracker Subsystem 8

GLAST LAT Project FM-B PSR, 10 Feb, 2005

Semi-disconnected channels (broken ladder wire-bonds)Semi-disconnected channels (broken ladder wire-bonds)

• 1 layer only (X5 – tray H037-Front)• ~60 bad channels which stabilized during tray thermal cycle and tower assembly• no further degradation during tower ENV tests• see NCR-368

Tracker Subsystem 9

GLAST LAT Project FM-B PSR, 10 Feb, 2005

Open NCRs related to disconnected/bad channelsOpen NCRs related to disconnected/bad channels

• Bad channels NCRs - proposed disposition is use as is and close :– INFN/PI-368 (tray Heavy 037)

• Last disposition (MRB 1/12/2005) is use as is for tower B; build ladders with no encapsulation and test on tower 1

• Disconnected channels NCRs – proposed disposition is use as is and close:

– INFN/PI-350 (tray MID 051)• 2 more channels lost in TVAC

– INFN/PI-346 (tray MID 043)• 24 more channels lost in tray thermal cycle and tower TVAC

– INFN/PI-384 (tray MID 023)• Large fluctuation in number of disconnect vs temperature

– INFN/PI-389 (tray Heavy 018)• 13 disconnected and 4 noisy found during TVAC test

Tracker Subsystem 10

GLAST LAT Project FM-B PSR, 10 Feb, 2005

ConclusionsConclusions

• Tower B was assembled, tested and shipped to SLAC in 2 weeks (2 more weeks were lost for the setup of the new Alenia TVAC chamber)

• No major issue were found in assembly, environmental tests, performance verification – a number of minor issues must be addressed before tower1 activities

• The overall number of bad channels is very low– New MCMs with no PA disconnection will reduce even more this

number and its stability with time/temperature– New heavy and bottom ladders with no wire-bond encapsulation

will show their reliability soon (tower1 trays data available next Monday right before assembly)