MiniBooNE Trigger Notes (Version 2.0)

Rex Tayloe, Andrew Green 2/20/03

Introduction

Find in this document the status of the trigger during the period 1/31/2003 to the present. An explanation of changes made to the MiniBooNE trigger during the January 2003 shutdown may be found in January shutdown work. See the prior version of this document for an explanation of the the trigger settings prior to the shutdown. See the references listed below for background information. References to particular pieces of C-code are given by name. Find these at the MiniBooNE CVS repository (Reference 5).

MiniBooNE Trigger for Run Period 2 (Starting 2/5/2003)

Find below the trigger settings that will be used after the January shutdown, in MiniBooNE Run Period 2, 02/03 - (DAQ CVS tag ?).

Detector comparator and external input settings:

Trigger bit

Setting

Trigger bit

Setting

DET1

# tank hits >= 10

VETO1

# veto hits >= 6

DET2

# tank hits >= 24

VETO2

# veto hits >= 4

DET3

# tank hits >= 40

E1

beam on neutrino target

DET4

# tank hits >= 100

E2

strobe (pulser)

DET5

# tank hits >= 60

E3

calibration

E4

hardware OR of Ebits

Notes:

Calibration activity types (using the E3 input to trigger):

Calibration Activity

Width of E3 pulse

Times E3 asserted to trig FIFO

Explanation

CALIB_CUBE

150ns

1 or 2

Prescaled cube trigger

CALIB_LASER

450ns

4 or 5

Normal

CALIB_TRACKER

650ns

6 or 7

Prescaled cube + 4-plane tracker coincidence OR just tracker

CALIB_BEAM

850ns

8 or 9

Laser in time with non-M'BooNE Booster shot

Notes:



The E bits are formed using discriminator and logic modules in a NIM crate above the trigger (VME) crate. The NIM logic pulses were set to be >=150ns and routed to the 4 BNC inputs of the trigger memory card.

Using these bits and appropriate logic within the trigger code, these "windows" and "holdoffs" are created.

Trigger Windows/Holdoffs:

Window name

Abbrev.

Definition (logical). T(*) indicates time since this activity in the trigger in u-sec.

Explanation

"beam holdoff"

BH

T(E1) <= 20

Holdoff of all other triggers during beam event.

"Michel window"

MW

3 <= T(DET4 .and. VETO1) <= 15

A cosmic ray candiate has occured in a window. Look for Michel electrons.

"SuperNova holdoff"

SNH

T(DET4 .or. VETO1) <= 15 .or. T(CALIB_LASER) <= 2

A cosmic ray or calibration event has occured in recent past. Holdoff SN triggers.

"Gamma/beta holdoff"

GBH

T(DET2 .and. VETO2) <= 15

A cosmic ray has occured in recent past. Holdoff Gamma and Beta triggers.

"Beam nu candidate"

BNuC

3.2 <= T(DET2) <= 8.6 within Beam event

A nu candidate in beam on window. Use for beta/gamma windows.

"Strobe nu candidate"

SNuC

3.2 <= T(DET2) <= 8.6 within Strobe event

A nu candidate in "strobe" window. Use for beta/gamma windows for accidentals.

"beam gamma window"

BGW

T(BNuC) <= 1000

A gamma after a beam nu candidate.

"strobe gamma window"

SGW

T(SNuC) <= 1000

A gamma after a strobe nu candidate.

"beam beta window"

BBW

1000 <= T(BNuC) <= 30000

A beta after a beam nu candidate.

"strobe beta window"

SBW

1000 <= T(SNuC) <= 30000

A beta after a strobe nu candidate.

"calibration cube window"

CalCuW

0.4 <= T(CALIB_CUBE) <= 0.8

Account for time delay between cube trigger (real time) and associated DET/VETO activity (sum PMT system takes ~6 cycles to compute detector sum).

Notes:


Using these status of the bits in the current trigger data word and the conditions of the various windows and holdoffs, triggers are formed.

Trigger Types:

Trigger event type

Trigger name

Condition (! = .not.)

Base TSA offset

# of TSAs broadcast

Explanation

1

beam

!BH .and. E1

0

192

Neutrino beam on target signal. This signal comes 5&mu;s before beam is on target so no addtional offset is needed.

2

strobe

!BH .and. E2

0

192

Pulser signal. Everything else just like beam triggers.

8

calibration: laser

!BH .and. CALIB_LASER

6

96

laser event

9

calibration: beam

!BH .and. CALIB_BEAM

0

96

Laser in time with non-MiniBooNE Booster shot

11

calibration: tracker

!BH .and. CALIB_TRACKER

-4

128

muon tracker 4-plane coincidence, plus cube (this varies)

12

beam gamma

!GBH .and. BGW .and. DET1 .and. !DET4 .and. !VETO2

0

32

gamma candidate following a beam nu candidate

13

beam beta

!GBH .and. BBW .and. DET2 .and. !VETO2

0

32

beta candidate following a beam nu candidate

14

strobe gamma

!GBH .and. SGW .and. DET1 .and. !DET4 .and. !VETO2

0

32

gamma candidate following a strobe nu candidate

15

strobe beta

!GBH .and. SBW .and. DET2 .and. !VETO2

0

32

beta candidate following a strobe nu candidate

10

calibration: cube

!BH .and. CalCuW .and. DET4

-5

128

Cube in time with DET4 tank hits.

4

Michel

!BH .and. MW .and. !VETO1 .and. DET2

-160

192

Muon decay Michel electrons. The TSA window is large enough to contain the parent (cosmic-ray) muon.

5

SuperNova

!BH .and. !SNH .and. !VETO1 .and. DET5

0

32

SuperNova candidate.

6

Tank

!BH .and. DET1

-96

192

Minimum bias tank tube trigger.

7

Veto

!BH .and. VETO1

-96

192

Minimum bias veto tube trigger.

Notes:

References

  1. LSND NIM paper: NIM A388, 149, '97.

  2. miniBooNE TDR

  3. "Data Acquistion Electronics and Programmer's Model, BooNE TN-038, Vern Sanberg, 2001.

  4. Slides from MiniBooNE analysis meeting, Rex Tayloe, 2/13/02, "http://www-boone.fnal.gov/software_and_analysis/meetings/02-13-02/minutes_02-13-02.html .

  5. MiniBooNE CVS Repository, Trigger Source Code, http://cdcvs0.fnal.gov/cgi-bin/public-cvs/cvsweb-public.cgi/miniboone/DAQ/target/trigger/src/" , and http://cdcvs0.fnal.gov/cgi-bin/public-cvs/cvsweb-public.cgi/miniboone/DAQ/share/src/"


Rex Tayloe

Last modified: Sat Feb 1 17:59:04 EST 2003