Tracker Subsystem1 GLAST LAT Project FM7/9 PSR, Sept. 9, 2005 GLAST LAT Tracker Tower7/9 Pre-Ship Review INFN-Pisa

Tracker Subsystem2 GLAST LAT Project FM7/9 PSR, Sept. 9, 2005 Tower 7 - Assembly and test highlights June 14 - July 4, 2005 (INFN-Pisa) : –assembly of complete tray stack –incomplete cable set (C0,C1,C2,C3,C4,C7) –Sidewalls, alignment July 7-15, 2005 (Alenia-Roma) : –VIB, TVAC test RUN I NCR 544 layerX17 noise anomaly July 25-26, 2005 (INFN-Pisa) : –Tray 17 replacement –C5 installation July 28 – August 31, 2005 (Alenia-Roma) –TVAC (7/28-8/4) RUN II –VIB (8/31) RUN II (Z axis only) September 1-5, 2005 (INFN-Pisa) : –C6 installation –Solithane, EMI taping –Alignment verification, final CPT Full EIDP details (soon) at: – Aluminum service sidewall tray17 replacement tray to be replaced

Tracker Subsystem3 GLAST LAT Project FM7/9 PSR, Sept. 9, 2005 Tower 7 – Environmental test runs configurations

Tracker Subsystem4 GLAST LAT Project FM7/9 PSR, Sept. 9, 2005 Tower 7 Delivery configuration Tower PN: LAT-DS (rev3) Tower SN: 7 Details on NCR 530

Tracker Subsystem5 GLAST LAT Project FM7/9 PSR, Sept. 9, 2005 Tower 7 – Configuration and mechanical verifications Alignment, Mass, COG: Tower 7 well aligned and inside stayclear Mass (32.705Kg) and CG near estimated values (when used real masses) Full data available from EIDP and INFN-PISA web site Configuration: Kapton tape and foam applied on the flex cables as per LAT-DS layers of Poron foam THK used on Bottom and Top Tray (–X) side (in place of 5 layers) Base Plate assembly: Torque of nuts 5.3 Nm, spec is ( /-0 Nm)

Tracker Subsystem6 GLAST LAT Project FM7/9 PSR, Sept. 9, 2005 Tower 7 – Open NCRs INFN/PI-530: environmental test in non-flight configuration –both environmental test runs were performed with missing cables, as agreed by an MRB –As a consequence of the missing solithane, 4 screws loss nominal torque and 1 was halfway unscrewed on one sidewall after Z-axis vibrations: the screws were re-torqued to spec and the following X and Y axis vibrations did not show any torque loss the NCR can be closed – the NCR can be closed INFN/PI-543: layer X7 not read out (TVAC RUN I) –X7 could not be readout at power up after vib test. X7 was properly read at the following and first switch on during TVAC –The problem is due to a known and documented issue with resetting MCM (NCR 417) with missing cables –To avoid the many and unknown number of power cycle needed to re-establish a good configuration with as many readable layers as possible, hot/cold switch on and off were not performed the NCR can be closed – the NCR can be closed INFN/PI-544: layer X17 noisy at hot soak (TVAC RUN I) –As per MRB decision, tray 17 (MID010) was replaced with a new tray, and tower7 retested –the NCR can be closed INFN/PI-570: cold/hot power off/on not performed (TVAC RUN II) –Same as NCR 543 –the NCR can be closed INFN/PI-547: Vacuum level out of specification (TVAC RUN I) –The situation is similar to earlier TVAC tests and the proposal is to accept the test as for previous MRBs. Tower 6 was tested with tower 7 RUN I and the same NCR was closed

Tracker Subsystem7 GLAST LAT Project FM7/9 PSR, Sept. 9, 2005 NCR 534: 2 layers (Y2, X5) sometimes out of spec due to fluctuations in noisy channels; the NCR can be closed X17 fixed after tray M010 replacement X5 showed 1 noisy ladder when ramping from 3 rd cold to 4 th hot soak: similar isolated anomalies, appearing randomly and only once were observed in other towers and are very likely caused by noise pickup dependent on the setup and/or the readout system (remember NCR 461 on the interference between the 2 towers DAQ causing test failures) Tower 7 – Bad channels

Tracker Subsystem8 GLAST LAT Project FM7/9 PSR, Sept. 9, 2005 Tower 7 - Efficiency All layers well within spec (eff > 98%) Differences correlated to bad channels No change after z-axis vib retest taken in Alenia after 2 nd TVAC

Tracker Subsystem9 GLAST LAT Project FM7/9 PSR, Sept. 9, 2005 Tower 7 TVAC – vacuum out of spec RUN I Same behaviour as previous tests – proposal is to accept the test: Vacuum slightly higher than spec (~> vs 5x10 -5 Torr) during hot soaks Vacuum level improving with time same pressure behaviour in dry run with MGSE Same behaviour as tower6 TVAC, accepted during preship review (corresponding NCR 546 was closed)

Tracker Subsystem10 GLAST LAT Project FM7/9 PSR, Sept. 9, 2005 Tower 9 - Assembly and test highlights July 8-15, 2005 (INFN-Pisa) : –assembly of complete tray stack –incomplete cable set (C0-non-flight,C3 missing,C7-non-flight) –Sidewalls, alignment July 25 – august 4, 2005 (Alenia-Roma) : –VIB, TVAC September 5-7, 2005 (INFN-Pisa) : –C0, C7 replacement with flight cables –C3 installation –Solithane, EMI taping –Alignment verification, final CPT Full EIDP details (soon) at: – tray to be replaced

Tracker Subsystem11 GLAST LAT Project FM7/9 PSR, Sept. 9, 2005 Tower 9 – Configuration and mechanical verifications Alignment, Mass, COG: Tower 9 well aligned and inside stayclear Mass (32.840Kg) and CG near estimated values (when used real masses) Full data available from EIDP and INFN-PISA web site Configuration: Kapton tape and foam applied on the flex cables as per LAT-DS layers of Poron foam THK used on Bottom and Top Tray (–X) side (in place of 5 layers) Base Plate assembly: Torque of nuts 5.4 Nm, spec is ( /-0 Nm)

Tracker Subsystem12 GLAST LAT Project FM7/9 PSR, Sept. 9, 2005 Tower 9 – Open NCRs INFN/PI-541: environmental test in non-flight configuration –environmental test were performed with missing cables, as agreed by an MRB –Missing cables are the consequence of the following NCRs the NCR can be closed – the NCR can be closed INFN/PI-560: cold/hot power off/on not performed –To avoid the many and unknown number of power cycle needed to re-establish a good configuration with as many readable layers as possible, hot/cold switch on and off were not performed after a satisfactory running condition was found –the NCR can be closed INFN/PI-559: layers X2 and X12 not read out –Despite the many power cycles it was never possible to reset the tower as to read these layers; when a practical configuration was found with all layers readable but these 2, TVAC was run with such two layers disabled –Post environmental test show no problem in the performance of these two layers (see next slide) –the NCR can be closed

Tracker Subsystem13 GLAST LAT Project FM7/9 PSR, Sept. 9, 2005 Tower 9 - Efficiency All layers well within spec (eff > 98%) Total bad channels in tower ~50