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Upgrade of Trigger and Data Acquisition Systems for the LHC Experiments. Nicoletta Garelli CERN. Acknowledgment & Disclaimer.

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upgrade of trigger and data acquisition systems for the lhc experiments

Upgradeof Trigger and Data Acquisition Systems for the LHC Experiments

NicolettaGarelli

CERN

XXIII International Symposium on Nuclear Electronics and Computing, 12-19 September 2011, Varna, Bulgaria

acknowledgment disclaimer
Acknowledgment & Disclaimer
  • I would like to thank David Francis, BenedettoGorini, Reiner Hauser, FransMeijers, Andrea Negri, Niko Neufeld, Stefano Mersi, Stefan Stancu and all other colleagues for answering my questions and sharing ideas.
  • My apologizes for any mistakes, misinterpretations and misunderstandings.
  • This presentation is far to be a complete review of all the trigger and data acquisition related activities foreseen by the LHC experiments from 2013 to 2022.
  • I will focus on the upgrade plans of ATLAS, CMS and LHCb only.

N. Garelli (CERN). NEC\'2011

outline
Outline
  • Large Hadron Collider (LHC)
    • today, design, beyond design
  • LHC experiments
    • design
    • trigger & data acquisition systems
    • upgrade challenges
  • Upgrade plans
    • ATLAS
    • CMS
    • LHCb

N. Garelli (CERN). NEC\'2011

lhc a discovery machine
LHC: a Discovery Machine

Goal: explore TeV energy scale to find Higgs Boson & New Physics beyond Standard Model

How: Large Hadron Collider (LHC) at CERN, with possibility of steady increase of luminosity large discovery range

CMS

LHC

  • LHC Project in brief
  • LEP tunnel: 27 km Ø,~100 m underground
  • pp collisions, center of mass E = 14 TeV
  • 4 interaction points  4 big detectors
  • Particles travel in bunches at ~ c
  • Bunchesof O(1011) particles each
  • Bunch Crossing frequency: 40 MHz
  • Superconducting magnets cooled to 1.9 K with 140 tons of liquid He. (Magnetic field strength ~ 8.4 T)
  • Energy of one beam = 362 MJ (300x Tevatron)

Alice

SPS

ATLAS

PS

LHCb

N. Garelli (CERN). NEC\'2011

lhc today design beyond design
LHC: Today, Design, Beyond Design

1

2

Interventions needed to reach design conditions

b* = beam envelope at Interaction Point (IP), determined by magnets arrangements & powering. Smaller b*= Higher Luminosity

LHC can go further  Higher Luminosity

N. Garelli (CERN). NEC\'2011

lhc schedule model
LHC Schedule Model
  • Yearly Schedule
  • operating at unexplored conditions  long way to reach design performance  need for commissioning & testing periods
  • one 2-month Technical Stop (TS). Best period for power saving: Dec-Jan
  • every ~2 months of physics a shorter TS followed by a Machine Development (MD) period necessary
  • 1 month of heavy ion run (different physics program)
  • Every 3 years a 1 year long (at least) shutdown needed for major component upgrades
  • … and the experiments?
  • profit from LHC TS & shutdown periods for improvements & replacements
  • LHC drives the schedule  experiments schedule has to be flexible

N. Garelli (CERN). NEC\'2011

lhc towards design conditions
LHC: Towards Design Conditions
  • Don’t forget that life is not always easy
    • Single Event Effects due to radiation
    • Unidentified Falling Objects (UFO), fast beam losses
  • What LHC can do as it is today:
    • with 50 ns spacing: nb = 1380, bunch intensity = 1.7 1011, b* = 1.0 m L = 5 1033 cm-2s-1 at 3.5 TeV
    • with 25 ns spacing: nb = 2808, bunch intensity = 1.2 1011, b* = 1.0 m L = 4 1033 cm-2s-1 at 3.5 TeV
  • Not possible to reach design performance today:
    • Beam Energy: joints between s/c magnets limits to 3.5 TeV/beam
    • Beam Intensity: collimation limits luminosity to ~5 1033 cm-2s-1 with E = 3.5 TeV/beam

N. Garelli (CERN). NEC\'2011

lhc draft schedule consolidation
LHC Draft Schedule –Consolidation

LCH activities

after Shut-Down

Long Shut-Down

Upgrade Phases

  • fully repair joints between s/c magnets
  • install magnet clamps

E = 6.5-7 TeV

L = 1034 cm-2s-1

2013

CONSOLIDATION

  • Electrical fault in bus between super conducting magnets caused 19.9.2008 accident  limit E to 3.5 TeV
  • After joints reparation 7 TeV will be reached, after dipole training: O(100) quench/sector  O(month) hardware commissioning

N. Garelli (CERN). NEC\'2011

lhc upgrade draft schedule phase1 2
LHC Upgrade Draft Schedule – Phase1&2

LCH activities

after Shut-Down

Long Shut-Down

Upgrade Phases

  • fully repair joints between s/c magnets
  • install magnet clamps

E = 6.5-7 TeV

L = 1034

New collimation system necessary to be protected from high losses at higher luminosity

CONSOLIDATION

2013

  • collimation upgrade
  • injector upgrade (Linac4)

E = 7 TeV

L = 2 1034cm-2s-1

2017

PHASE 1

  • new bigger quadrupoles smaller b*
  • new RF Crab cavities

E = 7 TeV

L = 5 1034cm-2s-1

PHASE 2

2021

N. Garelli (CERN). NEC\'2011

lhc upgrade draft schedule
LHC Upgrade Draft Schedule

LCH activities

after Shut-Down

Long Shut-Down

Upgrade Phases

  • fully repair joints between s/c magnets
  • install magnet clamps

E = 6.5-7 TeV

L = 1034cm-2s-1

CONSOLIDATION

2013

  • collimation upgrade
  • injector upgrade (Linac4)

E = 7 TeV

L = 2 1034cm-2s-1

2017

PHASE 1

  • new bigger quadrupoles smaller b*
  • new RF Crab cavities

PHASE 2

The Super-LHC

E = 7 TeV

L = 5 1034 cm-2s-1

2021

3000 fb-1 by the end of 2030

x103wrt today

N. Garelli (CERN). NEC\'2011

lhc experiments design
LHC Experiments Design
  • LHC environment (design)
    • sppinelastic ~ 70 mbEvent Rate = 7 108 Hz
    • Bunch Cross (BC) every 25 ns (40 MHz) ~ 22 interactions every “active” BC
    • 1 interesting collision is rare & always hidden within ~22 minimum bias collisions = pile-up
  • Stringent requirements
    • fast electronics response to resolve individual bunch crossings
    • high granularity (= many electronics channels) to avoid that a pile-up event(1) goes in the same detector element as the interesting event(1)
    • radiation resistant

(1) Event = snapshot of values of all front-end electronics elements containing particle signals from single BC

N. Garelli (CERN). NEC\'2011

lhc upgrade effects on experiments
LHC Upgrade: Effects on Experiments
  • Higher peak luminosity  Higher pile-up
    • more complex trigger selection
    • higher detector granularity
    • radiation hard electronics
  • Higher accumulated luminosity  radiation damage: need to replace components
    • sensors: Inner Tracker in particular (~200 MCHF/experiment)
    • electronics? not guaranteed after 10 y use

Challenge for experiments: LHC luminosity x10 higher than today after second long shutdown (phase 1)

2013

2014

2017

2018

2021

2022

N. Garelli (CERN). NEC\'2011

interesting physics at lhc
Interesting Physics at LHC

Total (elastic, diffractive, inelastic) cross-section of proton-proton collision

Higgs ->4m

DESIGN ~22 MinBias

Find a needle …

…in the haystack!

BEYOND DESIGN  5x bigger haystack

~100 MinBias

Cross-section of SM Higgs Boson production

Fluegge, G. 1994, Future Research in High Energy Physics, Tech. rep

N. Garelli (CERN). NEC\'2011

trigger data acquisition daq systems
Trigger & Data Acquisition (DAQ) Systems
  • @ LHC nominal conditions  O(10) TB/s of data produced
    • mostly useless data (min. bias events)
    • impossible to store them
  • Trigger&DAQ: select & store interesting data for analysis at O(100) MB/s
    • TRIGGER: select interesting events (the Higgs boson in the haystack)
    • DAQ: convey data to local mass storage
    • Network: the backbone, large Ethernet networks with O(103) Gbit & 10-Gbit ports, O(102) switches
  • Until now: high efficiency (>90%)

40 MHz

O(10)TB/s

Trigger & DAQ

Local Storage

O(100)MB/s

CERN Data Storage

N. Garelli (CERN). NEC\'2011

comparing lhc experiments today
Comparing LHC Experiments Today

ATLAS

CMS

LHCb

Similar read-out links

ATLAS: partial & on-demand read-out @L2

CMS & LHCb: read-out everything @L1

N. Garelli (CERN). NEC\'2011

atlas trigger daq today

Trigger Info

ATLAS Data

ATLAS Trigger & DAQ (today)

Trigger

DAQ

ATLAS Event

1.5 MB/25 ns

Calo/Muon Detectors

Other Detectors

<2.5 s

Level 1

40 MHz

40 MHz

Detector Read-Out

FE

FE

FE

L1 Accept

75 (100) kHz

ROD

ROD

ROD

75 kHz

Regions Of Interest

112 GB/s

Data-

Flow

High Level Trigger

ReadOut System

~40 ms

Level 2

ROI data

(~2%)

ROI Requests

Event Builder

~ 3 kHz

~4.5 GB/s

Data Collection Network

L2 Accept

~3 kHz

~4 sec

SubFarmInput

Event Filter

Event Filter Network

EF Accept ~200 Hz

SubFarmOutput

~ 300 MB/s

~ 200 Hz

CERN Data Storage

N. Garelli (CERN). NEC\'2011

cms trigger daq today
CMS Trigger & DAQ (today)
  • LV1 trigger HW:
    • custom electronics
    • rate from 40 MHz to 100 kHz
  • Event Building
    • 1st stage based on Myrinet technology: FED-builder
    • 2nd stage based on TCP/IP over GBE: RU-builder
    • 8 independent identical DAQ slices
    • 100 GB/s throughput
  • HLT: PC farm
    • event driven
    • rate from 100 kHz to O(100) Hz

Detectors

40 MHz

O(s)

Level 1

Trigger

Front-End pipelines

Read-out buffers

100 kHz

Switching Networks

O(s)

High Level Trigger

Processors farms

Mass storage

100 Hz

N. Garelli (CERN). NEC\'2011

experiments challenges beyond design
Experiments Challenges Beyond Design
  • Beyond design  new working point to be established
  • Higher pile-up  increase pattern recognition problems
  • Impossible to change calorimeter detectors (budget, time, manpower)
  • Necessary to change inner tracker
    • current damaged by radiation
    • needs for more granularity
  • Level-1 @ higher pile-up  select all interesting physics
    • simple increase of thresholds in pTnot possible: lot of physics will be lost
    • more sophisticated decision criteria needed
      • move software algorithms into electronics
      • muon chambers  better resolution for trigger required
      • add inner tracker information to Level-1
  • Longer Level-1 decision time  longer latency
  • More complex reconstruction in HLT
    • more computing power required

N. Garelli (CERN). NEC\'2011

daq challenges
DAQ Challenges
  • Problem:
    • which read-out ?
    • at which bandwidth?
    • which electronics?
  • Higher detector granularity higher number of read-out channels  increased event size
  • Longer latency for Level-1 decisions  possible changes in all sub-detector read-out systems
  • Larger amount of data to be treated by network & DAQ
    • higher data rate  network upgrade to accommodate higher bandwidth needs
    • need for increased local data storage
  • Possibly higher HLT output rate if increased global data storage (Grid) allows

N. Garelli (CERN). NEC\'2011

as of today difficult planning
As of Today: Difficult Planning
  • Hard to plan
    • while maintaining running experiments
    • with uncertain schedule
  • Upgrade plans driven by
    • Trigger: guarantee good & flexible selection
    • DAQ: guarantee high data taking efficiency
  • New technologies might be needed
    • Trigger: new L1 trigger & more powerful HLT
    • DAQ: read-out links, electronics &network
  • To be considered
    • replacing some components may damage others
    • new architecture must be compatible with existing components in case of partial upgrade

N. Garelli (CERN). NEC\'2011

slide21

ATLAS

AToroidalLHC ApparatuS

N. Garelli (CERN). NEC\'2011

atlas draft schedule consolidation
ATLAS Draft Schedule – Consolidation

ATLAS Activities

TDAQ related

after Shut-Down

Long Shut-Down

Upgrade Phases

  • TDAQ farms & networks consolidation
  • Sub-detector read-out upgrades to enable Level-1 output of 100 kHz
  • Current innermost pixellayer
    • will have significant radiation damage, largely reduced detector efficiency
    • replacement needed by 2015
    • Insertable B-Layer (IBL) built around a new beam-pipe & slipped inside the current detector

E = 6.5-7 TeV

L = 1034 cm-2s-1

2013

CONSOLIDATION

N. Garelli (CERN). NEC\'2011

evolution of tdaq farm
Evolution of TDAQ Farm
  • Today: architecture with many farms & network domains:
    • cpu&network resources balancing on 3 different farms (L2, EB, EF) requires expertise
    • 2 trigger steering instances (L2, EF)
    • 2 separate networks (DC & EF)
    • huge configuration
  • Proposal: merge L2, EB, EF within a single homogeneous system
    • each node can perform the whole HLT selection steps
      • L2 processing & data collection based on ROIs
      • event building
      • event filter processing on the full event
    • automatic system balance
    • a single HLT instance

To be approved

N. Garelli (CERN). NEC\'2011

tdaq network proposal
TDAQ Network Proposal

ROS

ROS

ROS

ROS

ROS

ROS

  • Current network architecture:
    • system working well
    • EF core router: single point of failure
    • new technologies
  • 2013: replacement of cores mandatory (exceeded life-time)

DC

SV

SV

SFI

SFI

XPU

XPU

EF

EF

EF

XPU

XPU

PU

XPU

PU

PU

XPU

XPU

PU

XPU

  • Proposal:merge DC&EF networks  OK with new chassis
    • some cost reduction
    • perfect for TDAQ farms evolution
    • mixing functionalities
    • reduce scaling potential with actual TDAQ farms configuration

SFO

EF

SFO

N. Garelli (CERN). NEC\'2011

atlas upgrade draft schedule phase1
ATLAS Upgrade Draft Schedule – Phase1

ATLAS activities

TDAQ related

after Shut-Down

Long Shut-Down

Upgrade Phases

  • TDAQ farm & network consolidation
  • L1 @ 100 kHz
  • IBL

E = 6.5-7 TeV

L = 1034cm-2s-1

2013

CONSOLIDATION

  • Level-1 Upgrade to cope with pile-up after phase-1
    • New muon detector Small Wheel (SW)
    • Provide increased calorimeter granularity
    • Level-1 topological trigger
    • Fast Track Processor (FTK)

E = 7 TeV

L = 2 1034 cm-2s-1

2017

PHASE 1

N. Garelli (CERN). NEC\'2011

new muon small wheel sw
New Muon Small Wheel (SW)
  • Muon precision chambers (CSC & MDT) performance deteriorated
    • need to replace with a better detector
  • Exploit new SW to provide also trigger information
    • today: 3 trigger stations in barrel (RPC) & end-caps (TGC)  New SW = 4th trigger station
    • reduce fake
    • improve pT resolution
    • level-1 track segment with 1 mrad resolution
  • Micromegas detector: new technology which could be used

N. Garelli (CERN). NEC\'2011

Small Wheel

l1 topological trigger
L1 Topological Trigger
  • Proposal: additional electronics to have a Level-1 trigger based on topology criteria, to keep it efficient at high luminosities: Df, Dh, angular distance, back-to-back, not back-to-back, mass
    • di-electron  low lepton pT in Z, ZZ/ZW,WW, H→WW/ZZ/tt and multi-leptons SUSY modes
    • jet topology, muon isolation, …
  • New topological trigger processor with input from calorimeter & muon detectors, connected to new Central Trigger Processor
  • Consequence: longer latency, develop common tools for reconstructing topology both in muon & calorimeter detectors

Under discussion

N. Garelli (CERN). NEC\'2011

fast track processor ftk
Fast Track Processor (FTK)

Good match between

Pre-stored & Recorded

patterns

  • Introduce highly parallel processor:
    • for full Si-Tracker
    • provides tracking for all L1-accepted events within O(25μs)
  • Reconstruct tracks >1 GeV
    • 90% efficiency compared to offline
    • track isolation for lepton selection
    • fast identification of b & τ jets
    • primary vertex identification
  • Tracks reconstruction has 2 time-consuming stages:
    • pattern recognition  Associative memory
    • track fitting  FPGA
  • After L1, before L2
    • HLT selection software interface to FTK output (tracks available earlier)

Pattern from

reconstruction

Pre-stored patterns

Discarded patterns

N. Garelli (CERN). NEC\'2011

atlas upgrade draft schedule phase2
ATLAS Upgrade Draft Schedule – Phase2

ATLAS activities

TDAQ related

1. Full digital read-out of calorimeter (data & trigger)

  • faster data transmission
  • trigger access to full calorimeter resolution (provides finer cluster and better electron identification)

 proposed solution: fast rad-tolerant 10 Gb/s links

after Shut-Down

Long Shut-Down

Upgrade Phases

E = 6.5-7 TeV

L = 1034cm-2s-1

  • Reduce heterogeneity in TDAQ farms & networks

2013

PHASE 0

  • FTK
  • L1 Topological trigger

E = 7 TeV

L = 2 1034 cm-2s-1

2017

PHASE 1

  • 2. Precision muon chambers used in trigger logic  dismount as less as possible
  • 3. L1 Track Trigger

E = 7 TeV

L = 5 1034 cm-2s-1

2021

PHASE 2

N. Garelli (CERN). NEC\'2011

improve l1 muon trigger phase2
Improve L1 Muon Trigger – Phase2

Current muon trigger:

  • trigger logic assumes tracks to come from interaction point (IP)
  • pT resolution limited by IP smearing (Phase2: 50mm  ~150mm)
  • MDT resolution 100 times better than trigger chambers (RPC)

 Proposal: use precision chambers (MDT) in trigger logic

    • reduce rates in barrel
    • no need for vertex assumption
    • improve selectivity for high-pTmuons
  • Current limitation: MDT read-out serial & asynchronous

 Phase2: improve MDT electronics performance (solve latency problem)

  • Fast MDT readout options:
    • seeded/tagged methoduse information from trigger chambers to define RoI & only consider small # of MDT tubes which falls into the RoI. Longer latency
    • unseeded/untagged methodstand-alone track finding in MDT chambers. Larger bandwidth required to transfer MDT hit pattern

N. Garelli (CERN). NEC\'2011

track trigger phase2
Track Trigger – Phase2
  • Possible to introduce L1 track trigger  keep L1 rate @ 100 kHz
    • combine with calorimeter to improve electron selection
    • correlate muon with track in ID & reduce fake tracks
    • possible L1 b-tagging
  • L1 track trigger Self Seeded
    • use high pTtracks as seed
    • need fast communication to form coincidences between layers
    • latency of ~3ms
  • L1 track trigger ROI Seeded
    • need to introduce a L0 trigger to select RoI at L1
    • long ~10ms L1 latency
  • New Inner Detector
  • only with silicon sensors
  • better resolution, reduced occupancy
  • more pixel layers for b-tagging

N. Garelli (CERN). NEC\'2011

slide32

multi-jet event at 7 TeV

CMS

The Compact MuonSolenoid

N. Garelli (CERN). NEC\'2011

cms consolidation phase
CMS Consolidation Phase

CMS activities

TDAQ related

after Shut-Down

Long Shut-Down

Upgrade Phases

E = 6.5-7 TeV

L = 1034 cm-2s-1

  • Trigger & DAQ consolidation
  • x3 increase HLT farm processing power
  • replace HW for Online DB

CONSOLIDATION

2013

  • Muons
  • CMS design: space for a 4th layer of forward muon chambers (CSC & RPCs)
    • better trigger robustness in 1.2<|h|<1.8
    • preserve low pT threshold

N. Garelli (CERN). NEC\'2011

cms upgrade draft schedule phase1
CMS Upgrade Draft Schedule – Phase1

CMS activities

TDAQ related

after Shut-Down

Long Shut-Down

Upgrade Phases

  • Trigger & DAQ consolidation
  • 4th layer muon detectors

E = 6.5-7 TeV

L = 1034 cm-2s-1

CONSOLIDATION

2013

E = 7 TeV

L = 2 1034 cm-2s-1

  • New pixel detector
  • Upgrade hadron calorimeter (HCAL)  silicon photomultipliers. Finer segmentation of readout in depth
  • New trigger system
  • Event Builder & HLT farm upgrade

2017

PHASE 1

  • Phase-1 requirements&plans as ATLAS
  • radiation damage  change silicon innermost tracker
  • maintain Level-1 < 100 kHz, low latency, good selection  tracking info @ L1+ more granularity in calorimeters
  •  DAQ evolution to cope with new design

N. Garelli (CERN). NEC\'2011

cms new pixel detector phase1
CMS New Pixel Detector –Phase1
  • New pixel detector (4 barrel layers, 3 end-caps)
  • Need for replacement
    • radiation damage(innermost layer might be replaced before)
    • read-out chips just adequate for L=1034 cm-2s-1 with 4% dynamic data loss due to read-out latency & buffer  to improve
  • Goal
    • gives better tracking performance
    • improved b-tagging capabilities
    • reduce material using a new cooling system CO2 instead of C6F14

N. Garelli (CERN). NEC\'2011

cms new trigger system phase1
CMS New Trigger System – Phase1
  • Introduce regional calorimeter trigger
    • to use full granularity for internal processing
    • more sophisticated clustering & isolation algorithms to handle higher rates and complex events
  • New infrastructure based on μTCA for increased bandwidth, maintenance, flexibility
  • Muon trigger upgrade to handle additional channels & faster FPGA

moving from custom ASICs to powerful modern FPGAs with huge processing & I/O capability to implement more sophisticated algorithms

Advanced TelecommunicationsComputing Architecture (ATCA). Dramatic increase in computing power & I/O

N. Garelli (CERN). NEC\'2011

cms upgrade draft schedule phase2
CMS Upgrade Draft Schedule – Phase2

CMS activities

TDAQ related

after Shut-Down

Long Shut-Down

Upgrade Phases

E = 6.5-7 TeV

L = 1034 cm-2s-1

  • Trigger & DAQ consolidation
  • 4th layer muon detectors

CONSOLIDATION

2013

  • New pixel detector
  • Upgrade HCAL  silicon photomultipliers
  • New trigger system
  • EventBuilder&HLT farm upgrade

E = 7 TeV

L = 2 1034 cm-2s-1

2017

PHASE 1

  • Install new tracking system  track trigger
  • Major consolidation of electronics systems
  • Calorimeter end-caps
  • DAQ system upgrade

E = 7 TeV

L = 5 1034cm-2s-1

PHASE 2

2021

N. Garelli (CERN). NEC\'2011

new tracker
New Tracker

pass

fail

2

pass

fail

  • R/D projects for new sensors, new front-end, high speed link (customized version of GBT), tracker geometry arrangement
    • >200M pixels, >100M strips
  • Level-1 @ high luminosity  need for L1 tracking
  • Delivering information for Level-1
    • impossible to use all channels for individual triggers
    • Idea: exploit strong 3.8 T magnetic field and design modules able to reject signals from low-pTparticles
    • Different discrimination proposals to reject hits from low-pTtracks  data transmission at 40 MHz feasible:
    • within a single sensor, based on cluster width
    • correlating signals from stacked sensor pairs

1

~ 1 mm

N. Garelli (CERN). NEC\'2011

~ 100 μm

slide39

B0s meson  μ+ μ-

LHCb

The Large HadronCollider beauty experiment

N. Garelli (CERN). NEC\'2011

lchb trigger daq today
LCHb Trigger & DAQ Today

Single-arm forward spectrometer (~300 mrad acceptance) for precision measurements of CP violation & rare B-meson decays

  • Designed to run with average # of collisions per BX ~ 0.5 & nb~2600  L ~ 2 1032 cm-2s-1  running with L = 3.3 1032 cm-2s-1
  • Reads-out 10 times more often than ATLAS/CMS to reconstruct secondary decay vertices  very high rate of small events (~55 kB today)
  • L0 trigger: high efficiency on dimuon events, but removes half of the hadronic signals
  • All trigger candidates stored in raw data & compared with offline candidates:
    • HLT1: tight CPU constraint (12 ms), reconstruct particles in VELO, determine position of vertices
    • HLT2: Global track reconstruction, searches for secondary vertices

40 MHz

L0

e, g

L0

had

L0

m

HW

< 1 MHz

HLT1. High pT tracks with IP != 0

SW

30 kHz

Global reconstruction

HLT2. Inclusive & exclusive selection

3 kHz

Event size

~35 kB

N. Garelli (CERN). NEC\'2011

lchb upgrade phase1
LCHb Upgrade – Phase1
  • 2011: L ~O(150%) of design, O(35%) of bunches
  • after 2017: Higher rate  higher ET threshold  even less hadronic signals

Interesting physics with ~ 50 fb-1 (design: 5 fb-1):

  • precision measurements (charm CPV, …)
  • searches (~1 GeV Majorana neutrinos,…)

40 MHz

  • UPGRADE NEEDED
  • increase read-out to 40 MHz & eliminate trigger limitations
    • LLT will not simply reduce rate as L0, but will enrich selected sample
  • new VELO detector
  • no major changes for muon & calo
  • upgrade electronics & DAQ
    • data link from detector: components from GBTreadout-network made for ~ 24 Tb/s
    • common back-end read-out board: TELL40. Parallel optical I/Os (12 x > 4.8 Gb/s), GBT compatible

Calo, Muon

Custom electronics

LLT

pT of had, m, e,/y

1-40 MHz

All sub-detectors

HLT

Tracking, vertexing, inclusive/exclusive selections

CPU farm

20 kHz

N. Garelli (CERN). NEC\'2011

need for bandwidth phase2
Need for Bandwidth – Phase2

Read-out from cavern to counting room

  • New front-end GigaBit Transceiver (GBT) chipset
    • point-to-point high speed bi-directional link to send data from/to counting room at ~5Gb/s
    • simultaneous transmission of data for DAQ, Slow Control, Timing Trigger & Control (TTC) systems
    • robust error correction scheme to correct errors caused by SEUs
  • Advanced Telecommunications Computing Architecture (ATCA)
    • point-to-point connections between crate modules
    • higher bandwidth in output
  • Which electronics in 20 y? Will VME be still ok? Do we need ATCA functionality?

VME

ATCA

Ethernet ~40 Gb/s

Board

Board

Front-End

~200 Mb/s

S-link

~200 Mb/s

PC

Ethernet

1 Gb/s

GBT ~5 Gb/s

Read-Out System

~40 Mb/s

~40 Gb/s

N. Garelli (CERN). NEC\'2011

conclusion
Conclusion
  • Trigger & DAQ systems worked extremely well until now
  • After the long LHC shutdown of 2017:beyond design
    • increased luminosity
    • increased pile-up
  • Experiments need to upgrade to work beyond design
    • New Inner Tracker: radiation damage & more pile-up
    • Level-1 trigger: more complex hardware selection & deal with longer latency
    • New read-out links: higher bandwidth
    • Scale DAQ and Network
  • Difficult to define upgrade strategy as of today
    • unstable schedule
    • maintaining current experiments
  • One thing is sure: LHC experiments upgrade will be exciting

N. Garelli (CERN). NEC\'2011

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