Level1

Trigger system design specifications

1MHzTevatronCollisions

Level2

Level3 Tape

10kHz 1kHz 20-50Hz

Time budget for Level3 i/o, event building, filtering 100 nodes * 10-3 s = 0.1 s

Level 1 Framework

Two views of the Framework Racks

The L1 trigger logic is all performed on

a VME card

Level 1 Framework

1. The L1 Trigger associated with each detector examines every event. Decisions are reported as trigger terms (AND OR network) to the Framework (L1FW), which support 128 L1 trigger bits (0 or 1)

2. Each “L1 trigger bit” is programmed to require a specific combination of trigger terms. A series of FPGAs (field programmable gates arrays) examine the list of terms collected from CFT,CPS,CAL, MUON to determine If a L1 bit has been satisfied.

3. When L1FW issues an accept, the event data is digitized and moved into16-event buffers to await a L2 trigger decision

• Operation and General Architecture:

accept 10 kHz event rate ~~~ 1kHz

correlating info on found objects across sub-detectors

• Two processor stages

1. “worker” preprocessors prepare

Level1 data (50s decision time)

(CAL, Muon, tracking: CFT & CPS)

2. “global” processors combine L1 trigger objects from the detectors.

(75us decision time)

Level Two

highways operate at 320Mbytes/sec to provide the decision within 75s.

Individual preprocessors

CAL preprocessor Muons preprocessor Tracking preprocessor

building the jets and electron candidates;

calculating their energy

testing jets for shape

testing transverse energy requirement

Improving the Mouns identification by repeating the Level 1 calculation with more resolution and more information

Using the parallel architecture to provide an algorithm with execute time independent of detector hits

CFT : assembling PT or azimuthally order a list of trigger tracks before transmission to the global processor.

CPS: computing azimuth and rapidity of electrons candidate

L2 Global processor input

L2 fiber tracker tracks <2

L2 central preshower clusters in the CPS detector <1.2

L2 forward preshower clusters in the FPS detector 1.4~~2.5

L2 calorimeter (EM) electromagnetic clusters

L2 calorimeter (JET) jets

L2 calorimeter (MET) missing transverse energy

L2 muon (central) muons found in central region <1

L2 muon (forward) muons found in forward region 1~~2

Trigger & Data Acquisition Systems

Detector

L1 trigger

L2 trigger

L3 trigger

tape

1.7 MHz bunchcrossing rate

10 kHz L1 accept

1000 Hz L2 accept

50 Hz L3 accept

Jets Muon electron tracking

Missing ET, sum-ET

Silicon tracking

80-100 CPU’s

Jet finding

Full event reconstruction

Data Collection: Trigger & DAQ (Online) Data Reconstruction & Analyses (Offline)• Re-process data using more accurate calibrations

•Data storage

•Perform analyses

Current Rate Limitations

1400 Hz

Chosen to limit front end busy rates ( <5% )

800 Hz

system readout instability above 850 Hz

50 Hz above 35E30

60 Hz below 35E30, where additional rate is from B triggers

Forced by consideration of reconstruction limitations

W

e

e

You have all been working through an exercise of making

the W transverse mass plot

from data selected with Wee candidates

data that certainly came from single electron triggers…

L3 Trigger Name

L1 Trigger

L2Trigger L3 Filter Prescale

E1_SHT20E2_SHT20E3_SHT20

CEM(1,11)CEM(2,6)CEM(1,9)CEM(2,3)

none 1 EM object with Et>20 GeV andtight shower shape requirements with EM fraction of cluster > 0.9

1

E1_SH30E2_SH30E3_SH30

share same L1 bits

none 1 EM object with Et>30 GeVloose shower shape requirements with EM fraction of cluster > 0.9

1

E1_SHT15_M15E2_SHT15_M15E3_SHT15_M15

share same L1 bits

none 1 EM object with Et>15 GeV and tight shower shape requirements EM fraction of cluster is > 0.9missing pT > 15 GeV NADA applied at L3missing pT calculated relative to vertex reconstructed using L3 tracks with pT>3 Ge V

1

38 “flavors” of “single electrons” triggered on

L3 Trigger Name

L1 Trigger

L2Trigger L3 Filter Prescale

EM_HI_EMFR8 CEM(1,10) 1 EM object, Et> 12 GeV

1 EM object with Et>40 GeV and EM fraction>0.8

1-3

EM_HI shares same L1 bit

1 EM object, Et> 12 GeV

1 EM object with Et>30 GeV and EM fraction>0.9

1-3

EM_HI_SH shares same L1 bit

1 EM object, Et> 12 GeV

1 EM object with Et>20 GeV loose shower shape cuts and EM fraction>0.9

1-3

EM_HI_SH_TR shares same L1 bit

1 EM object, Et> 12 GeV

1 EM object with Et>12 GeV loose shower shape cuts EM fraction>0.9, and a track with pT>12 GeV

1-3

EM_HI_TR shares same L1 bit

1 EM object, Et> 12 GeV

1 track with pT>25 GeV 1-3

W

e

e

W

W

τ

τ

W

d

u

L3 Trigger Name L1 Trigger L2Trigger L3 Filter Prescale

mu1ptxatxx_ncu mu1ptxatxx (all region scint. trigger)

None none 757-33360

MT10W_L2M5_TRK10 mu1ptxwtxx TTK(1,10) (CFT track pT>10 GeV)

1 mediummuon withpT>5 GeV

L3 track with pT>10 GeV

1

MUW_W_L2M3_TRK10 mu1ptxwtlx (wide region scint. trigger w/ loose wire req’d)

1 medium muon withpT>3 GeV

L3 track withpT>10 GeV

1

MU_W_L2M3_TRK10 mu1ptxwtxx (wide region scintillator trgr)

1 mediummuon withpT>3 GeV

L3 track withpT>10 GeV

1-3

MUZ_A_L2M3_TRK10 mu1ptxatxx_fz (all region scintillator trigr fast Z coinc)

1 mediumMuon withpT>3 GeV

L3 track withpT>10 GeV

1-5

MU_A_L2M3_TRK10 mu1ptxatxx (all region scintillator trgr)

1 mediummuon withpT>3 GeV

L3 track withpT>10 GeV

1-15

~20 flavorsof single muon

triggers

October 2004

Jim Linnemann (Michigan State University) 7 years as convenor of the RUN I Level 2 trigger7 years as convenor of the RUN II Level 2 trigger

Daniel Claes (University of Nebraska) 5 years working on of the RUN I Level 2 trigger (under Jim)7 years as convenor of the RUN II Level 3 trigger

were tapped to co-convene the Level 2 Algorithms groupcharged with finding new (and new combinations of)

Level 2 triggers to provide needed rejection

The NEXT bottle neck is predicted to be maxing out Level 3 CPU time

With increased luminosity, not only will higher rates will be pushing through the system,but MORE COMPLICATED EVENTS putting the burden the L3 processing farm.

DØ Trigger Simulator ManualGetting Started

( The Cookbook Method )

The first thing you need to run TrigSim is a set of events to run it over. These can be either Monte Carlo (MC) generated or data taken online. The only requirement is that it be in "raw" form (i.e. <filename>.raw).

If you do not have a .raw data file, link to a file TrigSim managers use for debugging (the path is in the example below). The debug .raw file has 500 MC t-tbar events

created with MC version p10.11.00.

Choose a production release number to use. In p14 versions and earlier TrigSim runs as a single executable. In p15 (t03.08.00) and later, it runs as two executables:

one which does the trigger simulation and a second which creates the rootuple output.

Let's start with a newer version, say p15.01.00. Get your run environment setup by typing:

setup D0RunII p15.01.00 setup d0tools -t

Create a text file containing the path & file name(s) of your .raw file(s), one file per line. If you wish to use our MC sample, copy the platform-appropriate example filelist:

d0mino_default_mc_filelist.txt or clued0_default_mc_filelist.txt. The simulation part of TrigSim requires at least two arguements:

what file(s) to run on, and what format the events are. The valid format choices are mc and data. In this example, we will use mc. To run TrigSim, just type: runD0TrigSim -filelist=default_mc_filelist.txt -format=mc The outputs from this command will appear in a newly created directory whose name starts with D0TrigSim_x-.

http://www-d0.fnal.gov/computing/trigsim/trigsim.htmlTrigSim Documentation link from

Beside the online documentation and tutorialsour Fermilab postdoc

Angela Bellavance(who maintains those pages and serves as convenor of the TrigSim

effort)

will prove an excellent resource

This makes the project a very natural one for Nebraska students!