Send Mail to Ed ObrienPHENIX-MVD-96-9
Introduction The MVD minireview took place at BNL as part of the February PHENIX detector council meeting. We had a brief introduction by Barbara Jacak, a status report on detectors and electronics by Jon Kapustinsky, status of the detector mechanics by Jan Boissevain, cooling and Spring 96 beam test update by Jeanne Simon-Gillo and a summary by Barbara. Overall the MVD project is on schedule and close to its budget target. There is presently no technical issue that is impeding the project. The manpower on the MVD is sufficient in both quantity and quality to complete the project successfully. The experience and expertise on the MVD is very well matched to the project itself which should give PHENIX much confidence in the ultimate success of the detector. However, a project of this complexity is not without risk or potential difficulty. This report lists a number of recommendations and action items. Both the MVD group and PHENIX Project Management should consider acting on the recommendations and closely monitoring the issues listed as action items.
Detectors and Electronics The Silicon Strip and Silicon Pad development and production plan looks good. The company chosen for the silicon detector production, Micron Semiconductor, has produced similar detectors for other High Energy Physics experiments. There is a possibility to do the Si Pads in a double metal process that would eliminate the need for additional Kapton cables. 1) The MVD should seriously consider going to the double metal process for the Si Pads. It will be more reliable and though there are some additional up front costs in the long run it may be no more expensive.
The individual components of the MVD electronics are progressing well and are reasonably well in hand with the possible exception of the Multi-Chip Module (MCM). However, it is not clear that the schedules of the individual electronics components mesh well. 2) Both the MCM design and the cooling design are waiting for additional information from the ORNL group. Considering the importance of the MCM and cooling design ORNL should put high priority on providing the MVD group with the information needed to proceed on these two issues. Manpower on the MVD IC design is perhaps the one area where additional resources could make a important impact.
The MCM is the most technically challenging aspect of the project. Eight front-end IC's, eight AMU-ADC's and 1 FPGA are all packed into a 4.8 x 4.8 cm ceramic hybrid. This technology is not mature and there is only one vendor. 3)The MCM development should be most closely monitored by both the MVD group and PHENIX Project Management. The MVD group should develop a fall back plan in case difficulties arise with the technology or vendor. 4)The MVD Fee design review is important to the schedule. It should be done as soon as possible.
Mechanics The MVD mechanics is well developed. The design is good and the mechanical testing and simulation gives one confidence that the Rohacell supports will provide both the rigidity and stability the MVD requires. One should investigate whether Rohacell loses mechanical integrity due to radiation damage. The well planned program of mechanical testing should continue. An expanded MVD radial boundary was established at the PHENIX DC meeting. 5)A drawing showing the new MVD radial boundary should be produced by the MVD group and given to the PHENIX engineering and integration group.
Cooling and Beam Test There is still an outstanding issue of whether the MVD is cooled using air or water. The cooling tests up to now have been conducted with carefully designed test equipment that should be giving very realistic answers. All the necessary mechanics are in place to make the cooling decision once some additional information is available on the electronics power consumption. 6)Do not design the MVD cooling too close to the edge of specifications for acceptable air velocities and temperature levels. Allow for some unanticipated heat load increase in the future in the design. As was emphasized at the review, the cooling design is both an issue of heat load and radiation length budget.
The beam test plans look good for this year.
Schedule and Summary The MVD is currently on schedule and barring a technical problem, should be completed in advance of its installation in PHENIX. There is plenty of slack in the MVD schedule. 7)The MVD should consider adding a test with a large number of electronics channel (2-5k) to its testing plan. Otherwise the detector will go from a test with 256 channels to a detector with 30K channels, which is a big jump to make. Additionally, the MVD schedule implies chain tests involving connecting the detector to components of the DAQ. However, these tests are not explicitly on the schedule and should be added. 8)Time for tests involving MVD+MCM, MVD+DCM and MVD+DAQ should be added to the MVD schedule.
The MVD project is progressing well. All the resources are in place for a successful completion of the project, on schedule. A number of potentially difficult technical issues still exist that could delay the project, the cooling and MCM for instance. These few issues should be closely monitored. Otherwise, the project is in a very positive position.