2012 R&D and Upgrades

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 STAR called for R&D for FY13 in early September. The proposals received are given here.

STAR issued a call for proposal in  September. call text.

A number of proposals were received in no particular order

  1. Forward Calorimetry (UCLA)
  2. Hadronic forward calometry (Crawford)  Some additional information based on questions from STAR management on resolution
  3. Forward GEM for spin asymmetry (Underwood)
  4. High Level Trigger (Aihong Tang)
  5. iTPC (Zhangbu Xu, Jim Thomas)

A meeting is planned for October 22 to have these propodsal presented and evaluated by a STAR panel. The timescale for implementation is different, so criteria will be graded

There is a panel of people who agreed to review and discuss the proposals. We expect to have short presentation ~10-15 minutes for each proposal, followed by a question period. The panel consists of Dick Majka , Wei Xei,  Bill Llopez ,   Xin Dong  (F.Videbæk ex-offocio)

--- fast vertexing
Proposal from RICE blue sky
-- msg from Geary

Attached is a proposal from Blue Sky Electronics to provide STAR withsix channels of fast-vertex electronics for evaluation during Run 13.The electronics are based on an idea from Bill Llope that he found inthe literature. A 3 GHz flash ADC samples the PMT waveform. Astraight-line fit of the rising edge finds the start of the signal and
compensates for the slew. The concept and the electronics seem to work
quite well.

There are 3 PMT channels on each VPD currently that are not connected to aQT and L0. The plan would be to connect these six channels to the fast-vertexelectronics and provide an east and west time to trigger so that it can berecorded with the L0 trigger data. An 11-bit time and 3-bit PMT map would besent from each side. Jack Engelage has been looking this week for a suitableavailable connection in the existing DSM structure.

The electronics would sit on a shelf in 1B1 or 1B2 and be powered by a sparePL512 channel, or else a 25A Kepco. The RHIC clock would be accessed from a TCDfanout.

The fast-vertex electronics provides a ~100 ps start-stop measurement onlinefrom cosmic-ray cable-delay data, or ~70 ps for one side of that measurement.Lloyd Bridges and Bill Llope have analyzed the test data offline confirming theresult. Another week of testing over a range of cable delays is needed toconfirm this result.

Bill's calibration of the VPD shows a 100 ps single-channel resolution in AuAuand 140 ps single-channel resolution in pp. The HPTDC contributes 14 ps tothe single-channel resolution. Substituting 70 ps for 14 ps in the
single-channel resolution yields an expected online single-channel resolution
of 120 ps in AuAu and 155 ps in pp.

The vertex resolution in AuAu with an occupancy of 1/19 would be 2.6 cm and
0.65 cm with an occupancy of 16/19. [121ps*sqrt(2)/2/33ps/cm (/4)]. Theexpected vertex resolution in pp with 1/19 occupancy would be 3.35 cm.

Rice has M&O funds we can use to buy the PMT signal cables and we have
available power supplies so there should be no additional out-of-pocket cost
to STAR. We just need your support and the support of Bill Christie and Hank
Crawford and their groups. Hank should be aware of the project since it has
been discussed at trigger meetings for several years. It is mentioned inthe minutes from the trigger meeting last week.

It is possible but unlikely that the electronics will be ready by
January 8. However, we can get the cabling in place now and install the
electronics during an 8-hour maintenance access once the electronics are ready.Even a few weeks of data would provide proof of principle.

 The Buesky proposal is in the attachment to this page