Research on CMS - UCLA Physics & Astronomyhauser/homepage/DOE09_hauser_v2.pdf · DOE site review – Jay Hauser 30 Oct. 2009 31/38 Triggering with the ME4/2 upgradeTriggering with

DOE site review – Jay Hauser 30 Oct. 2009 1/38

Task E, part 2Task E, part 2

• Research on CMS• Farrell, Hauser, Jarvis, Smith, Perloff, Rakness


Hauser research teamHauser research team

• Postdocs Greg Rakness, Chad Jarvis

• Both resident at CERN• Supported by Task E

• Engineer John Smith• Here at UCLA• Supported by US-CMS M&O and

Upgrade funds

• Students Chris Farrell (grad), AlexxPerloff (undergrad)

• Currently resident in L.A.• Supported by Task E and M&O,

respectively


Research program: past & presentResearch program: past & present• CDF: 1990-2007 (created the UCLA group)

• Co-founder of CDF Exotics physics group• Plug calorimeter upgrade, esp. shower maximum• Supersymmetry searches (all-jets, multi-leptons), top mass with matrix

element method • Some publications below…


Research program: past & presentResearch program: past & present

• CMS since 1994, now sole research activity• Emphasis on the endcap muon system – cathode strip

chambers (CSC)• Created the CSC trigger electronics (1700 boards built

at UCLA)• Track Finder part split off Acosta at UF

• Responsible for CSC time synchronization• Responsible for CSC upgrades• ~2/3 of time in Geneva since Jan. 2008

UCLA work centers on the endcap muon

detectors

• 4x2 muon stations like that on right


US-CMS muon detector contributionUS-CMS muon detector contribution

• Cathode strip chambers (CSC) cover 1.0<η<2.4• Magnificent system of 468 chambers, 2.5M wires

(none broken), fast & reliable electronics


Research program: futureResearch program: future• Commission CSC with “first” data in 2009 and 2010:

• Tending the CSC trigger electronics: update firmware, fix boards• Rakness: the manager for CSC detector operations• Timing: big change from cosmic rays to collision muons• Trigger configuration: start with loose muon criteria, then tighten

• Physics interests using 2010 data:• Inclusive single muon spectrum at highest Pt• Slow penetrating particles in the endcap muon detector

• Management: • CMS muon upgrade co-leader, US-CMS “upgrade L3 manager”• Will be International CMS Project Manager for CSCs starting Jan.

1, 2010


Details that following and the corresponding Task E proposal sections

Details that following and the corresponding Task E proposal sections

• (Section 3) CSC electronics work

• (Section 4) CSC commissioning and operations

• (Section 5&7) physics analysis preparation

• (Section 8) upgrades

• (New) CSC management


CSC trigger schemeCSC trigger scheme

θ

ϕ

• Muon trigger measures momentum by curvature between stations• Low momentum muons are excluded (~10 MHz background)

• Two stations is absolute minimum• Three stations for minimal redundancy against

mismeasurement, multiple scattering, bremmstrahlung


(Section 3) CSC trigger electronics(Section 3) CSC trigger electronics

• 1700 programmable boards built and maintained by UCLA

• 3 types of UCLA boards• 468 boards each type plus

15-20% spares

• (14000 cathode trigger ASICs built by UCLA+CERN)

• (other boards built by Ohio State, CMU, Rice)


On-chamber trigger boardsOn-chamber trigger boards• ALCT board project: 468 boards, 3 variants

• 288-, 384-, and 672-channels each• Boards are re-programmable• 10-15% spares

• Boards needing repair are shipped back to UCLA


In 9U VME “peripheral crates”In 9U VME “peripheral crates”• Trigger Motherboards (TMB) and transition (RAT) boards

• 9 boards of each type in each of 60 crates• Fully programmable

lTTMB= Trigger Mother Board

RAT= Rpc + AlctTransition board

Cathode data inputs RPC data

inputs

ALCT data inputs


Recent electronics workRecent electronics work

• ALCT board test station restoration• Had been idle for ~4 years• Two stations now up and running• Special tester boards, firmware, and software

• About 30 ALCT boards debugged and fixed• Some boards never made to work previously• Some boards were returned from CERN• Good electronics training for the students

• 19 TMB boards returned from CERN for repair• Will be done by next month

Farrell and Perloff

Smith

Laboratory diagnosis and repair tools – $17K “stimulus” item


Electronics firmwareElectronics firmware

• Continuous process of improvements• Most recently (2009):

• Error-correcting code for ALCT TMB trigger and data paths in continuous operation

• New testing mode exhaustively tests all TMB—ALCT “Skewclear” cable pairs

• Numerous faulty cables were found and fixed or replaced

• ALCT clock phase adjustment to match muon time-of-flight

• “Muonic” timing for better control of CSC synchronization

Smith


(Section 4) CSC commissioning and operations

(Section 4) CSC commissioning and operations

• Led by Rakness for ~2 years thus far• ~100 people involved• 24/7 operation first started in August 2008• Big system (468 chambers, ~500,000 electronics

channels on ~12,000 boards, cables, gas, HV, LV, etc.)• Exhausting job – must be semi-expert on every topic

• Successes:• Large majority of the system works smoothly• Our detector furnished the baseline trigger for first

LHC beam


Rakness’ job:Rakness’ job:• Called as last resort when nobody else can solve a problem• Supervises:

• 24/7 shift operations manager• Team of CEOs “Csc Expert Operator” that rotate weekly• Deals with individual shift personnel (21-42 shifts/week)• This organization cuts down on wear & tear on Greg

• Runs the Tuesday CSC operations meetings• Represents CSCs at the Friday run coordination meetings• Daily planning meeting to discuss, e.g.:

• On-detector work• Updates to software versions• Safety system tests• Tests of new firmware• Computer network outages• Computer upgrades• Gas system interruptions• Cooling water leaks• Movements of the endcap iron disks• Power outages• Online databases• Coordination with RPC detector work• Fixes to the low-voltage and high-voltages systems

Sept. 2008 dataCSC triggers on beam halo muon

One endcap zoomed

cathode hits6 layers

anode hits6 layers

Sept. 2008 dataCSC triggers on beam halo muon

Both endcaps shown

LHC single beam dumped into upstream collimatorCreates “monster” event in which nearly all channels are lit up

The pink lines are CSC segments. There are O(170k) hits in each of these events.


A Brief History of TimeSynchronization of the CSC Detector

A Brief History of TimeSynchronization of the CSC Detector

• 13.73 billion years passed, then…• Beam tests 1999-2002:

• Timing-in took 1-2 weeks per chamber• Slice Tests in 2007:

• Techniques developed for rapidly measuring most timing parameters

• During 2008: • First timing-in 468-chamber CSC system• UF procedure to precisely align (cosmic)

muon stubs at the SP• During 2009:

• Development of “muonic” timing• Front-end clocking phase = muon TOF

• Accuracy:• Last year ±25 ns ±5 ns just recently• Desired: ±2 ns allows reliable

determination of the right bx with beam


Time alignmentTime alignment

• Some 20,000 timing parameters to be set• Anode hit fine delays with 2ns/tick• Cathode-anode time matching • Readout timing for cathode, anode, trigger

• First: align the trigger• Individual chambers:

• Pulse test strip• Natural radioactivity and 1-layer trigger

• Between chambers: TOF relevant, use cosmic rays

• Then align the readout timing

TMB #1ALCTTOFdelay

TMB #2ALCTTOFdelay

Master clock

collisionAt BC0

ALCT1

ALCT2

TMB #1

sync

TMB #2

syncMuonfrom BC0

TMB BC0 out

TMB BC0 returnAligned!

BC0 timing diagram:

TX2 bc0 delay

TX1 bc0 delaytx1 TOF delay

tx2 TOF delay

S2 Skewclear delayS1 Skewclear delay

TMB clocks

ALCT clocks

S2 Skewclear delay

S1 Skewclear delay

rx1 TMB-in phase

rx2 TMB-in phase

RX1 input data delay

RX2 input data delay

CSC #1 CSC #2

Physical connections:

time

(bx)

Muonic timing: 2 CSCs, TMB ALCT


(Sections 5&7) Physics Analysis Prep.(Sections 5&7) Physics Analysis Prep.

• Main effort thus far is on single extreme-PT muons• Obvious signal for W′ particles: possibly competitive with

Tevatron in first data run • A prime model-independent signal of new physics

• Challenges:• Susceptible to rare tracking errors where curved muon track

appears nearly straight• High flux of isolated, moderate-PT muons from ordinary W and Z

decay and top quarks• Problem is highly dependent on alignment precision

• Hard to define fully data-driven method• Z μμ sample mismeasurement “easily” identified• Fewer events than W μν so can only place upper limit on the

mismeasurement probability


Some investigationsSome investigations• Track detail display:

• Effect of optimized track selection cuts:

Jarvis


…more investigations…more investigations• Badly mis-reconstructed tracks

• Pt(true)<100 GeV/c, Pt(reco.)>300 GeV/c• “hot spots” in η−φ found, being investigated

• Also:• Verified small tails for Tracker and Tracker-plus-1st muon station• Sensitivity to W′ in first data run• Sensitivity of results to alignment


Early physics:slow penetrating charged particles

Early physics:slow penetrating charged particles

• Signal:• Penetrating so look like muons, but

v<c so timing is slower

• We (UCLA) are expert on CSC timing:

• Cathode timing (Deisher)• Fit to pulse shape• Time calibration is important

• Anode timing (Rakness)• Bx digitization RMS=10 ns per

plane, but ~20 planes per track• RMS 5 ns using digitization of both

edges of 35ns discriminator?

17 Jun 09

• Suppose gravitinos G̃ are the LSP

• WIMPs freeze out as usual

• But then all WIMPs decay to gravitinos afterMPl

2/MW3 ~ seconds to months

SUPERWIMP RELICS

Like WIMPs: a particle (gravitino) naturally gets the right relic densityUnlike WIMPs: If WIMP is charged, signal is CHAMP, not MET

G̃WIMP≈

17 Jun 09 Feng 27

Well motivated – e.g. this talk (J. Feng at LPC)


Endcap Muon SLHC Upgrade (needs updating)

Endcap Muon SLHC Upgrade (needs updating)

• LHC maximum luminosity increased 2-5x• CERN “phase 1” new focusing quads and new linac• Ready by 2013

• Three main tasks for muon upgrade:1. Build ME4/2 chambers (72)2. Upgrade electronics for high-rate ME1/1 chambers3. Upgrade ME1/1 off-chamber cards for high rate


ME4/2 and ME1/1 muon stationsME4/2 and ME1/1 muon stationsME4/2 and ME1/1 muon stations

Iron ready for ME4/2 chambers

R-Z cross-section:• ME4/2 to be built• ME1/1 electronics upgrade


Three tasks to upgrade muons:Three tasks to upgrade muons:1) Build ME4/2 chambers (72)

• for high-luminosity triggering over η range of 1.1-1.8

• improve μ reconstruction

7.5”2) Replace ME1/1 cathode cards

with Flash ADC version• restores trigger to η 2.1-2.4• handles highest rates

3) Update off-chamber electronics for ME1/1• accomodate new cathode cards• improve trigger and data handling


Triggering with the ME4/2 upgradeTriggering with the ME4/2 upgradeTriggering with the ME4/2 upgrade• Plot below shows trigger rate at L=2*1034 with ME4/2 (3/4 stations) vs.

without ME4/2 (2/3)• Triggering on n out of n stations is inefficient and uncertain

• The Level 1 trigger threshold is reduced from 48 18 GeV/c (!)• With the ME4/2 upgrade, we can still capture W, Z, top, etc. events

Target Rate 5 kHz


Progress on CSC upgradeProgress on CSC upgrade• Chamber production tooling revived at Fermilab• ME4/2 infrastructure mostly prepared (UW)• One prototype built by Fermilab

• Installed with 4 spare chambers to investigate performance, background rates and trigger conditions

• Tooling to be shipped to CERN in few months• Discussions regarding ~1000 m2 space at CERN

• Digital CFEB prototype being built (Ohio State)• High-luminosity simulations helpful (Texas A&M)• CD0 document written and sent in to DOE Sept. 09


(New) JH as CSC Project Manager(New) JH as CSC Project Manager

• Nominal term is 2 years• Nominated by Spokesperson, confirmed by CMS

Management and Collaboration Boards• Previous managers were Mitselmakher, Loveless

• Top priorities:1. Maintain good communication within the group2. Optimize CSC collision data

• Requires a transition from “commissioning” to “operations”

• Requires more emphasis on data analysis and rapid feedback to detector operations

3. Concentrate on specific areas to strengthen


CSC PM: communicationsCSC PM: communications• Member of CMS Management Board

• “Global” CMS issues CSC group• CSC group issues attention of all of CMS (rarely)

• Relations with US-CMS L3 manager Padley• Co-management relationship needs full info. sharing• Example: recent update of Level 3 managers group

• See next slide - addition of Bob Clare (UC Riverside), MishaIgnatenko (UCLA)

• Relations with CSC collaborators• Dubna, PNPI St. Petersburg, and IHEP Beijing

• Data analysis:• Oversight of CSC Detector Performance Group (DPG)• Closely related to Muon Physics Object Group (POG)


CSC organizationCSC organization

• PM: Hauser (intl) and Padley (U.S.)• Deputy U.S. PM: Loveless• New “Level 3” structure:

• Rakness (UCLA) Operations Manager• Lanaro (UW) CSC Field Coord., Mechanical systems• Borcherding (FNAL) Electrical systems• Durkin (OSU) Electronics systems• Geurts (Rice), Clare (UCR) Online systems• Prokofiev (FNAL) Chambers• Ignatenko (UCLA) Chamber and electronics maintenance• Cox (Davis) CSC/DPG coordinator• Valuev (UCLA) CSC/POG contact• Hauser (UCLA) Upgrades• Korytov (UF) Special technical advisor


CSC PM: optimize collision dataCSC PM: optimize collision data• Endcap muon detectors have often been ignored in past

experiments…• E.g. in 2008 and 2009 much more barrel muon results from cosmic rays • CMS endcap covers a large range ☺ (η from 1.0 to 2.4)

• Up-time and data quality:• Problems thus far have been rare

• Robust CSC detector technology, well-built system • Trigger efficiency optimization:

• Concern about barrel-CSC overlap region – commissioned late, only modest software tools

• Concern about timing (must not trigger at wrong bunch crossing)• Data analysis optimization:

• DPG: Software tools are incomplete• Offline determination of fine timing is still under development• Muon POG: Muon ID cuts and relationship to alignment• Effects of neutrons and other sources of background hits• Groups are quite small


CSC PM: specific areas to strengthenCSC PM: specific areas to strengthen

• Part of overall shift from commissioning to a running detector

• Online shift crew interfaces• Several talented online programmers in CSC• Main issue is for guidance: what do we want?

• Simple event display• Need for something fast and portable, not 3D

• Hardware alignment• Several management structures in past• Expect to handle as “distributed” system in CSC like the trigger:

has mechanical, electronics, software aspects

• Documentation continues…• encourage detector-related publications, and locate deficiencies

in Twiki pages, etc.


SummarySummary• Muon detector commissioning increasingly

sophisticated (Rakness)• Muon trigger electronics working well

• Repairs and improvements of firmware (engineers)

• Muon system timing increasingly accurate• JH, Jarvis

• Muon SLHC upgrade effort is underway

• Expect to have some time to do early physics, e.g.:• Single muon Pt spectrum (Jarvis, Farrell)• Slow penetrating particles (Rakness, JH)

Documents

Research on CMS - UCLA Physics & Astronomyhauser/homepage/DOE09_hauser_v2.pdf · DOE site review – Jay Hauser 30 Oct. 2009 31/38 Triggering with the ME4/2 upgradeTriggering with