VTX Meeting Sept 7 2004 Robert Pak PHENIX

VTX Meeting Sept. 7, 2004 Robert Pak

PHENIX Central Region From VTX Proposal (dims in mm) HBD is standalone VTX Meeting Sept. 7, 2004 Robert Pak

VTX Barrel Geometry 14 cm 2. 5 cm GEANT by VR VTX Meeting Sept. 7, 2004 Robert Pak

VTX Barrel Specs Not updated in proposal VTX Meeting Sept. 7, 2004 Robert Pak

VTX Endcap Geometry VTX Meeting Sept. 7, 2004 Robert Pak

How VTX fits VTX layout changed, but envelope remains the same VTX Meeting Sept. 7, 2004 Robert Pak Lots of comment s about this

Space for the TPC is being squeezed by the need to bring out services for the VTX and the need for space for the readout electronics Planar GEM tracking chambers h = 0. 35 From: C. Woody h = 0. 70 h = 0. 88 10 -15 cm h = 1. 17 h = 2. 6 Provides tracking coverage over -2. 6 < h < 2. 6 VTX Meeting Sept. 7, 2004 Robert Pak

Be Beam Pipe Quote VTX Meeting Sept. 7, 2004 Robert Pak

Mylar Sleeve • Proper grounding & isolation of Si detector • Image charge from circulating beam • Aluminized Mylar sleeve around Be beam pipe • Few mm’s thick to hold down material budget • Grounded w/ braid through magnet • No interference with other sub-systems; st VTX Meeting nothing else between beam pipe and 1 Sept. 7, 2004 Robert Pak

VTX Mechanical Support Structure • Frame for barrel & end caps (HYTEC and LANL) • External support structure in central magnet (BNL) • Mechanical tolerances/distortions: • < 25 mm internally • ~4 x this amount relative to the rest of the detector • From CAD Survey Group (F. Karl): • 50 – 100 mm on Robert the bench Pak VTX Meeting Sept. 7, 2004

VTX Mech Support Structure (cont) • Modular design is necessary: • Easily removable from IR • Barrel and end caps mount separately • Mounted off of pole tips/nose cone calorimeter • To maintain specified tolerances • Alternate scheme proposed at Vanderbilt Meeting VTX Meeting Sept. 7, 2004 Robert Pak

Alternate Mounting Scheme From: van Hecke TPC mounts from top CM yoke. VTX Si detector comes in from bottom, much like MVD does now. Translate or clamshell? VTX Meeting Sept. 7, 2004 Robert Pak

Engineering for VTX • Decision on mounting scheme requires engineering • PHENIX hiring engineer to replace P. Kroon (retiring) • Work on PHENIX central region, which includes VTX • Engineering specific to VTX will be done at LANL(? ) • In consultation with new PHENIX engineer VTX Meeting Robert Pak Sept. 7, 2004 • Point of contact with HYTEC

VTX Design Issues • Circulated spec sheet compiled by D. Lee for CDR: • Heat Load (mainly due to readout chips): • 0. 35 W/cm 2 for strip layers; Vince concurred • 0. 70 W/cm 2 for pixel layers; Hiroaki concurred • Consistent with nos. in proposal • Mechanical tolerances/distortions: < 25 mm • Disassembly/configuration options: D. Lee has discussed modularity with HYTEC • Need to finalize before next round with VTX Meeting HYTEC Robert Pak Sept. 7, 2004

VTX Auxiliary Systems • Services routed radially at the pole tips: • Power for Si detectors (proper grounding & isolation): • Si HV & LV power supplies (Stony Brook & RIKEN) • UPS (BNL) • Cooling system for Si • Dry Air System • Bleed boil off from LN 2 buggy into enclosure • Radiation Monitoring • TLDs & Chipmunks VTX Meeting Sept. 7, 2004 Robert Pak

Routing for Services From: van Hecke Power, cooling and signal services are brought in at both ends, using the entire perimeter. VTX Meeting Sept. 7, 2004 Robert Pak

Infrastructure for VTX • • Electronics racks Platforms above central magnet Cooling for electronics Power for aux sys (proper grounding & isolation): • Clean & dirty power • 110 V & 208 V • Ballpark estimate: pixels draw 60 A and strips draw 400 A • UPS VTX Meeting Sept. 7, 2004 Robert Pak

VTX Design Issues Revisited • Circulated revised spec sheet: o • Cooling system operating temperature: < 10 C (Junkichi) • Current draw from Junji and Dave: What’s correct? VTX Meeting Sept. 7, 2004 Robert Pak