finuda trigger

FINUDA TRIGGER

FINUDA Collaboration MeetingTrieste, May 6-7 2004

Simonetta Marcello - Torino

Simonetta Marcello - TorinoPaola Gianotti - LNFFulvio Pompili - LNFAldo Zenoni (MC) - BresciaFrancesca De Mori (OA) - Torino ….….

FINUDA TRIGGER Strategy

SELECTIVE TRIGGER based on fast detector (TOF) and electronics

MODULAR and PROGRAMMABLE STRUCTURE to have a flexible configuration

CARE of TRIGGER DESIGN from the beginning to cope with high rates (up to 30

MHz) Dedicated MC SIMULATION

physical events, background (Touschek) [2000: G.Gomez- 2003: A. Zenoni]

Latency ~ 200 ns at First Level

RF signal not used at all in the Logic (due to old FEE on detectors) RF: 380 MHz (interbunch time 2.6 ns) rate ~ 400 Hz , interaction time 2 ms HYP rate < 1Hz Bhabha < 200 Hz

Asynchronous Trigger (continous source of events)

FINUDA TRIGGER - Simonetta Marcello - TS 6/5/04

L = 1032 cm-2 s-

1

Accurate TIMING is CRUCIALto select events from background

For more details: ISEO 2002

Level 0 selection is made using TOFINO signals here trigger is asynchronous

Level 1 selection includes TOFONE signals synchronization is given by level 0

TRIGGER STRATEGY

Selections• energy loss• topology • multiplicity• tof (In-Ext barrels)

Mean Timing signals

to identifiy hit slabs


ISEO

200

2

TIMING alignmentReference:photodiode

Gated OR TOFONE

TOFINO LThr MT

TOFINO HThr MT

MLUExclusiveBTB 1-1

BTB (Bhabha, not used for triggering)

PALExclusiveBTB 1-3 BTB (Bhabha + KsKl)

OR-MB

PALNOT ExclBTB 1-3 K+K-

OR-EL

PCoin narrow window

OR-TOFONE

Prompt Coincidence (less +)Slow Coincidence (only +)

MULT SEL HYP 2-7

HYP Mult

MULT SELBHABHA 2-7

BHABHA Mult

MALUGate fromOR Tofino DISC MULT TOFONE > 1

TOFONE MT


LASER

TRIGGER LOGIC

COSM

HYP

BHABHA

LASER

OR TOFONE

MULT TOFONE > 1

OR TOFINO

BASICTRIGGER

S

TRIGGER LOGIC


BTB Bhabha

MULT Bhabha

BTB K+K-

MULT HYP

OR MB

MULT TOFONE > 1

OR TOFONE

LASER PhDiode

PLUSyste

m

+

PRESC

Moduli VME (Heart of Trigger Logic)progettati e realizzati da Silvano Gallian Electronic Lab - Torino INFN)

Pattern Recognition LE297 BtB Topologies OK

Multiplicity Selector LE308 HYP, BHA multiplicities OK

Prescaler LE312 prescaling triggers OK

Prompt Coincidence LE301 tof Tofino-Tofone Not working in CRoom!

Already repaired, it still gives problems of noise.New tests and/or design needed Estimated time 6 m.u.


Rate TOFINO~ 400 kHz !

SELECTION OF HYP EVENTS

Background rejection for HYP Trigger

Events Acceptance Rate (Hz)HYP 0.35 ~ 0.1Bhabha 10-4 0.04KSKL 3x10-4 0.05 4x10-4 0.03+-0 10-4 0.001K+K- 7x10-2 15Touschek 1.5x10-6 0.3

Rates @ L = 1032cm-2s-1

Highrejection power

MC

ISEO

200

2


Real HYP TRIG Rate~ 7 Hz @ L ~ 4x1031cm-2s-1

RUN 2003-0

4

cut Bhabha K+K- KSKL Touscheknone 1000 1000 1000 100000imult =2 981 523 368 2327BtB 864 306 84 2emult 2-7 739 171 60 0tof 739 138 55 0not eloss 739 18 55 0tofgeo 611 5 10 0

acceptance 0.74 0.02 0.06 < 2x10-7

SELECTION OF BHABHA EVENTS

Background rejection for Bhabha Trigger

Rate @ L = 1032cm-2s-1

Events Rate (Hz)Bhabha 60K+K- 4KSKL 8Touschek < 0.04

MC

ISEO

200

2


Real BHABHA TRIG Rate

~ 15 Hz @ L ~ 4x1031cm-2s-1

RUN 2003-0

4

MaybeTofino efficiency for mip

?

TRIGGER Efficiency for BHABHA selection


Pattern Recognitionexclusive BTB 1-3 Topologies95% evaluated on TDC hits98% evaluated on MT hitsMultiplicity Selector * BTB1-3Mult 2-7 on Tofone90% evaluated on TDC hits99% evaluated on MT hits ? evaluated on MT hits inside Tofino gate

Need of TOF Calibration

Beam Runs Dec 2003with Trigger ORTofino*ORTofone

TRIGGER EFFICIENCY

What about Trigger Efficiencyfor HYP selection ?

Maybe not enough statistics onBeam Runs 2003-04with Trigger ORTofino*ORTofoneWe have to check including last runs


TRIGGER EFFICIENCY

Trigger Timing


MT Tofino (jitter/jump ~ 10 ns)

MT Tofone (jitter < 2ns)

Timing Alignment with LASER Maybe due to CFD

?

Between Tofino and Tofone(Basic Trigger signals)

FINAL Timing Alignment with with beam collisionsDue to not “safe calibrated” optical fibers

Loose Timing

Need of TOF Calibrationto measure real length of fibers

SELECTION OF HYP EVENTS

prompt-

• Fast coincidence (tof) custom VME module• Multiplicity >= 1 (Ext TOF) custom VME module

+ from K+ decayprompt-

tof Inner-Outer Barrels

K+ mean lifetime = 12.4 nsM

C

ISEO

200

2

Trigger Timing

Common STOP


Programmable Choiceusing Output Register CES1320 + ST03

OR Tofino (Physics , Cosmics)

OR Tofone (Cosmics)

Photodiode (LASER)

RF (not used, but read out on dedicated TDC)

8 double ANDs, 1 gateProgettato e realizzatoda Fulvio Pompili (INFN-LNF)

Safe Timing > 10 ns

TO BE or NOT TO BE


RF for Physics (on all TDCs)

OR

RF not used, but read out on dedicated TDC

Times with Physics Meaning TOF (particle time of flight between Tofino and Tofone)

Computing differences RF expires NO advantage

Resolution still depends on Tofino and Tofone ones

Higher Levels of Trigger


Maybe useful at 3rd Level

TOF used at 1st LevelLMD and STB not useful alone at 2nd Level

SIL most interesting information to be manageat 2nd Level, BUT unfortunately too slow (> 15 ms)

TOF again at 2nd Level ?

Filippini/Panzarasa TALK

Do we need a strict selection ?

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