AMS Tracker Data Reduction Status Claude Zurbach Laboratoire de Physique Théorique et Astroparticules – Montpellier Houston, AMS-TIM, January 08, 2007.

AMS

Tracker Data Reduction

Status

Claude ZurbachLaboratoire de Physique Théorique et Astroparticules – Montpellier

Houston, AMS-TIM, January 08, 2007

Summary

Calibration, gain test and reduction on Tracker detector Constraints and expected functionalities : calibration Constraints and expected functionalities : data reduction Procedures for development and test Example of online data reduction Next (and last ?) issues

Claude Zurbach - LPTA - TIM AMS - January 2007

Calibration, gain test and reduction on TrackerCalibration, gain test and reduction on Tracker


Calibration module

- Pedestal, raw and final noise determination- Quality flag setting- production of tables for the data reduction : pedestal, sigma, thresholds and

flag tables

Data Reduction module

signal (> threshold) = Amplitude – Pedestal – Common Noise

- calculation of final common noise uses tables of final sigma, pedestal and flag- identification and extraction of event clusters to transfer reduced data to the

AMS DAQ

Test gain module (DAC Calibration)

injection of a well defined signal and measure of the response of the scale

- Positioning of channels in test mode and measure of the amplification of the electronics of the scale

Constraints and expected functionalities : calibrationConstraints and expected functionalities : calibration

Calibration module version 6B1E : general design


Pedestal calculation : 1024 events

Sigma raw calculation + flags : 1024 events

Sigma final calculation + flags : 2048 events

Non Gaussian calculation : 2048 events

Tables of thresholds calculation

Step 1: call

Step 2: call

Step 3: call

Step 4: call

Step 5: call

Constraints and expected functionalities : calibrationConstraints and expected functionalities : calibration

Calibration module version 6B1E

Input data are coming from:

Gate Array memory - Amplitudes (1024+1024+1024+2048) - Low and High parameters for thresholds

Output data:

Table of Pedestals

Table of Sigma raw threshold

Table of Flags

Tables of low and high final Sigma thresholds

Constraints:

Time computing

Changing of thresholds values by control word

Reading of the tables

Calibration modulePedestals, sigma raw, sigma final, flags, low and high sigma thresholds calculations

Sigma rawthresholds

Low thresholds

Signal amplitude

High thresholds

Gate Array

External BufferPedestals

Thresholds parameters(constants)

Flags


Constraints and expected functionalities : reductionConstraints and expected functionalities : reduction

Reduction module version 6B1E : general design


Pedestal subtraction and reordering

Common Noise calculation

Cluster identification, construction and storage

CN values storage

Step 1: call

Step 2: call

Step 3: call

Step 4: call

Constraints and expected functionalities : reductionConstraints and expected functionalities : reduction

Reduction module version 6B1E


Data Reduction moduleAmplitude reading Pedestal subtractionCommon noise calculationCandidate identificationCluster constructionOutput transfer

Clusters AMS DAQ

Flags 0,1 …

Low thresholds

Signal amplitude

High thresholds

Gate Array

External Buffer

Pedestals

n(Sigma Raw)

Input data are coming from:

Calibration module : High and Low Thresholds, Pedestals, Flag tables

Gate Array memory : Signals containing clusters

Output data:

The length for each cluster, its first channel address, the channel values

The CN values of 16 VA

The total length of buffer

Constraint:

Time computing less < to 14.5 DSP KCycles (Last version in test : average < 11.5 KCycles)

Procedures for development and testProcedures for development and test


Organization

MIT – A. Kounine

DAQ, AMSWire protocol, software supervision … UNIGE – D. Hass

TRD Test and integration

Test level 2 (**) and validation calibration-reduction

PERUGIA – G. Ambrosi, P. Zuccon, P. Azarello

DAC Calibration integration

Test level 2 and validation calibration-reduction

Software specifications

LPTA – C. Zurbach

Tracker Data Reduction development

Test level 1 (*)

(*) Test level 1 : calibration with testbench, reduction with simulation

(**) Test level 2 : calibration and reduction with scales, on cosmic rays, sources or beams



Development and test scheme

INFN Perugia : charges specifications

MIT-CERN : constraint specification or implementation of new functionalities

UNIGE Genova and INFN Perugia : test of calibration-reduction, validation for integration

LPTA Montpellier : in coordination with UNIGE, development and test in simulation

LPTA-UNIGE : debugging, correction, adaptation …



Testbench



Simulation in reduction

Channel 0 Channel 1023

Specific cases : < 12 DSP Kcycles for totality of these clusters

Worst case : 66 DSP Kcycles for more than 512 clusters …

Low threshold High threshold

Example of online data reductionExample of online data reduction


Beam test September 2006 in Perugia : example of online reduction

Common noise on a subset of 64 channels :by average of the first 32 good channels (without flag and < than 4 sigma threshold)

Clusterization :seed found with high threshold 4 sigmaneighbours with low threshold 2 sigmaadjacents channels with no condition

Next issuesNext issues


Test recuperation of calibration tables for the aims of data reconstruction

Improve behaviour of code in situation of « worst case » in conformity with constraint of time and volume of data

Improve protection of code in case of error (example : checking the content of tables)

Improve, if possible, time computing to get flexibility on flight

AMS Tracker Data Reduction Status Claude Zurbach Laboratoire de Physique Théorique et Astroparticules – Montpellier Houston, AMS-TIM, January 08, 2007.

Documents

tim ams

expected functionalities

data reduction moduleamplitude

data reduction procedures

reduced data

thresholdsoutput data

tablesclaude zurbach

testclaude zurbach lpta