UCLA meeting, 2012 Hauser 1

Since last weekSince last week

• Technical Coordination workshop• Gave talk on CSC upgrades

• New 2013 timeline – ME4/2 seems okay, ME1/1 is tight, see next page

• TMB rates• Evaldas measuring rates for restricted TMB patterns

UCLA meeting, 2012 Hauser 2

2013 CSC Major Tasks2013 CSC Major Tasks

UCLA meeting, 2012 Hauser 3

23-Nov-2012 Update CSC Gantt Chart from Martin23-Nov-2012 Update CSC Gantt Chart from Martin

UCLA meeting, 2012 Hauser 4

Selected Milestones, early 2013Selected Milestones, early 2013

• A tentative & partial list of what seems “reasonable” to allow the work to proceed smoothly:

• Dec: Junction Box prototype finished, design verified

• TBD (Dec-Jan): PRR for DCFEB

• Feb: Patch panel prototype verified

• Feb: ESR (Electronics Status) and MPR (Manuf. Progress) reviews

• Mar: ODMB revised pre-production board w/Cu interface

• Associated software needs to be written in advance

• Mar: Software migrated from ME4/2 to ME1/1 FAST testing

• Apr: SX5 area ready to receive ME1/1 chambers

• May: production of half of the DCFEB, LVDB7, LVMB7

• May: pre-production of 12 ODMB, OTMB for test setups

• Work on a more detailed CSC-specific schedule is ongoing

UCLA meeting, 2012 Hauser 5

TMB Pattern Narrowing Test – draft talkTMB Pattern Narrowing Test – draft talk

• TMB trigger patterns (LCTs) are “broad” for every chamber• This gives maximum efficiency at lowest muon momentum (P~5 GeV)

• Inner chamber patterns could be narrowed with small efficiency loss – P is larger (for given PT), and magnetic bending is less

• Rates are highest on the inner chambers (ME1/1, 2/1, 3/1, 4/1)

• Want to request special run(s) to investigate the effect of narrowing TMB patterns• During low-luminosity collisions following Machine Development

• In the shadow of 5 hrs requested by Pixel detector to understand their radiation damage

UCLA meeting, 2012 Hauser 6

Goals of the Pattern Narrowing TestGoals of the Pattern Narrowing Test

• Reduce CSC event size • By reducing the number of CFEB and TMB readouts per

event (especially out-of-time)

• Currently marginal, will improve with elimination of DCC bottleneck, but event growth could be non-linear

• Input to HL-LHC trigger studies• Decide if replacement of all CFEBs is necessary ($6-8M)

• Change L1A latency (3.26, 10, or 20 s) and L1A rate (1001000 kHz)?

• Critical issue is the use of the 96 buffers in the Switched Capacitor Array (SCA) ASIC used on CFEBs

• Storage of analog charge in 50 ns “buckets”

• Affected by CLCT “pretrigger” rate

UCLA meeting, 2012 Hauser 7

CSC Readout Fragment SizesCSC Readout Fragment Sizes

FED753 FED750

• Affected by pile-up (soft muons, neutron hits, etc.)• FED753 (ME4/2) anomalous due to ME4/2

• No shielding wall, so many back-scattered particles• So ME4/2 chambers were split between FEDs

• With and without ALCT zero-suppression• FED753 ~2.72.0 kB, more typical FED 2.01.7 kB• -15% reduction, typically

Stan Durkin CMS Upgrade Week

8

16 Cap Delay Cap Storage (Poisson) Cap Digization (Queue)

Beam Crossing LCT L1A·LCT

0.8sec 2.2sec 26sec

Transfer toDMB Complete

Caps can be usedfor storage whenall others in use

For SLHC this is themain capacitor usage

Data Bottlenecks in CSC DAQ at SLHC

• CFEB’s 96 Capacitors/channel is main DAQ rate limiter

• DCC’s SLINK-64 is second DAQ rate limiter (configurable)

Simple Model CFEB Capacitor Storage

UCLA meeting, 2012 Hauser 9

CFEB Readout InefficiencyCFEB Readout Inefficiency

• 0.001 may beacceptable, 0.01 is bad

UCLA meeting, 2012 Hauser 10

Rate PlotsRate Plots• Vadim – sim - rates

integrated over rings• Bug fix factor of 2 applied

• 19E6 Hz at 8E34 L

• i.e. 11.9E6 Hz at 5E34 L

• ME2/1 has 36 chambers, so 330 KHz/chamber at 5E34 L

• Misha – data – rates per chamber• 30E3 Hz at 4.1E33 L

• i.e. 365 kHz/chamber at 5E34 L

UCLA meeting, 2012 Hauser 11

Rates for LCTs in ME2/1 at 5E34Rates for LCTs in ME2/1 at 5E34

Which estimate

Type of LCT ME2/1 Rate

Energy (TeV)

Data Matched 365 kHz 8

2002 Stan / Cousins et al.

CLCT* 525 kHz 14

2011 Khotilovich

Matched, tightened**

330 kHz 14

• Rates per chamber at 5E34 luminosity Data/sim comparisons are “reasonable”

• Rates are likely to be a little higher than “data”…

• Pretrigger requires 3 layers, not 4 (LCT)

• Unknown increase from 8 to 13 TeV

• (Rate per CFEB: nominally divide by 5, but there is an edge overlap factor ~1.2-1.4 not included)

*CLCT vs. matched makes little difference. NB this was for an earlier version of TMB patterns that were wider.

**TMB patterns 8-10 only, “skinny ALCT pattern”, factor of 2 for both endcaps applied

UCLA meeting, 2012 Hauser 12

TMB Pattern Test Thus FarTMB Pattern Test Thus Far

• B904 ME2/1 cosmic rays• Rate dropped 124 Hz with TMB pattern >=8

(TMB::CLCT_PID_THRESH_PRETRIG=8)

• P5 cosmic rays• ME4/2 see 32 Hz

• Writing flash (new patterns) on ME2/1, 3/1, 4/1

• took 21-27s per crate, so whole inner system ~13-14 min estimated

• Pattern distributions in CSCTF data• Show plot from old Anna presentation for low-Pt muons …

rather even by pattern #

UCLA meeting, 2012 Hauser 13

TMB Pattern Test Plan With CollisionsTMB Pattern Test Plan With Collisions

• Use low-luminosity collisions after MD

• In shadow of 5-hour pixel radiation damage test

• Change patterns on inner (ME1/1, 2/1, 3/1, 4/1) chambers and ME4/2

• Will affect most but not all FEDs, so can see event size difference with/without ME4/2 contribution

• ME4/2 a bit strange because outer chamber, and might suffer more efficiency loss

• Tighten + endcap (w ME4/2) to patterns 8-10 only• Leave the other endcap alone as a reference

• Then loosen to patterns 6-10 only