Requirements

rhig.physics.yale.edu

Requirements

Current status of

PHOS Online

Processing

Øystein Djuvsland Djuvsland, Per Thomas

Hille.

07 NNov 2007


Requirements: Calibration data

during ordinary runs

� Energy distribuiton for all channels

� 35840 histograms

� Update frequency: All events (1 KHz)

� HLT or DAQ

� TOF distribution for all channels.

� 35840 histograms

� Update frequency: All events (1 KHz)

� HLT or DAQ

� AAccumulated l t d energy ffor all ll channels, h l

� one histogram.

� Update frequency: All events (1 KHz)

� HLT or DAQ

Live channel map

� Live channel map

� one histogram

� Update frequency: All events (1 KHz)

� HLT or DAQ

� Summary:

� Summary:

� 71682 histograms must be updated at 1 KHz

� Status: Implemented and sucessfully tested in HLT


Requirements: Pedestal

calibration run

� Average Baseline measurements

� 35840 values

� 35840 histograms

� HLT or DAQ

� RMS of pedestals

�� 35840 values

� 35840 histograms

� HLT or DAQ

� Di Distribution t ib ti of f per channel h l mean pedestals d t l

� 35840 Values

� 35840 Histograms

� HLT or DAQ

� Frequency

� Can be adjusted j to available CPU ppower


Requirements: Data Quality

Monitoring

� The lesson learned from real data taking is that the quality of the data has to be

verified on event by event basis for each individual channel. It is not enough to

base the DQM on statistics accumulated during calibration run.

�� Some channels is noisy for all events events.

� Some APD are bad and give signals that is not due to any external events

(breakdown), however

� These channles also measure physical events

One has to discriminate between pysical and non physical events channel by channel

� One has to discriminate between pysical and non physical events channel by channel

and event by event.

� For some channels there are bit flips during readout.

� Should be corrected online in HLT prior to analysis by intelligent algorithms.

� Some channels has corrupted or bad signal for some events but are ok for

others.

� Summary:

� The DQM has to run in HLT because there are no mechanism to correlate corrupted

The DQM has to run in HLT because there are no mechanism to correlate corrupted

single events between HLT and DAQ.

� Status: Intelligent DQM algorithms has been implemented and sucessfully tested in the

HLT.


Requirements: Calibration data

for cosmic runs

� The requirements for Energy, Live channel map and accumulated energy

is simlar too those for Ordnary runs but the updtae frequency is less, only

20 – 100 Hz.

� Data compression & selection

� Data compression & selection.

� Selection of signals above noise.

� HLT

� Discarding bad data

� HLT

� Triggering on Isolated MIPS

� HLT

� Status:

� Status:

� The Online Data selection and compression has been implemented and

successfully tested online in HLT.

� The comsic MIP trigger has been successfully tested offline on HLT output data.


Preliminary conclusion

� Calibration algorithms for ordinary runs and

baseline calibration runs can run either in

HLT or DAQ.

�� Calibration algorithms for cosmic calibration

runs has to run in the HLT.

� Needs more CPU time than can be provided by

DAQ.

� DQM has to run in HLT


Calibration DAs for ordinary

run: HLT vs DAQ discussion

� Case 1: The DAs run in the HLT

� The data has to be made available for analysis

(decoding etc..) regardless of where the DA is

running. i Th The overhead h d of f running i th the DA DAs iin HLT

is relatively small compared to the CPU time

needed for reconstruction

reconstruction.

� Case 2: The DAs run in DAQ

� Decoding, mapping etc... Has to be done twice.

Once in HLT and once in DAQ


Calibration DAs for calibration

run: HLT vs DAQ discussion

� The DAs can be run in either HLT or DAQ


SSome real l life lif examples

l


APD in continious breakdown mode


Noisy APDs due to missing HV


Bit flip during readout


Cosmic event


Pi0 ?


HLT calibration display

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