MOLLER DAQAug 2015 meeting

Team : R. Michaels, P. M. King, M. Gericke, K. Kumar

R. Michaels, MOLLER Meeting, Aug, 2015

Overview of DAQ SystemTwo separate DAQs , some signals (e.g. detectors) go to both. 1. Production mode integrates over helicity period2. Counting mode for tracking studies and Q2

Also: test stands for detectors, beamline, DAQ development, etc

Trigger

TriggerSupervisor (CODA)

Detector VME

Injector VME

Beamline VME

Online Farm / Event builder

Tape Silo

CODA Configs: crates alone or in groups expect ~6 crates

~ 1000 TByte

• 1 cpu Event Building• 50 cpu online analysis• 50 TB volatile disk• 20 TB staging disk

DAQ Requirements

Production mode• zero deadtime at 2 kHz rate (helicity reversals)• 600 - 800 ADC channels, 5 MB/sec/crate x 6 crates• Negligible contribution to noise (<< 200 ppm counting stats per

azimuthal sector )

• Similar to Qweak, but a higher data rate like CLAS

Counting mode 10 - 300 kHz trigger, depending on mode

FADCs, regular ADCs, TDCs, I/O, scalers. R. Michaels, MOLLER Meeting, Aug, 2015

DAQ StrategyProduction mode• Capitalize on experience of Qweak, HAPPEX, PREX.• Need to write specification for integrating ADCs and

auxiliary electronics : timing control and I-to-V converter• In the meantime, test setups can use Qweak or HAPPEX

DAQ elements.

Counting mode• Prefer to avoid Fastbus.• Deploy pipelining FADCs, VETROC. Also, scalers, I/O, etc.

R. Michaels, MOLLER Meeting, Aug, 2015

From Qweak: TRIUMF VME integrator

FPGA

FPGA Prog/Debug Ports

VME Module SelectSwitches

Status LEDsVME AccessExt Clock EnbExt Gate Enb

Ext NIM Gate

Ext NIM Clock

DC-DCConverter

AnalogFilters

8 inputs

ADC

See proposal

for specification

From Qweak: TRIUMF VME integrator

FPGA

FPGA Prog/Debug Ports

VME Module SelectSwitches

Status LEDsVME AccessExt Clock EnbExt Gate Enb

Ext NIM Gate

Ext NIM Clock

DC-DCConverter

AnalogFilters

8 inputs

ADC

Good module with excellent specs• May improve design with modern chips ( obsolescence )• A faster readout is likely and desired (to increase from limit

of 10 boards per crate) • Need engineering support and a procurement strategy (current plan: TRIUMF )• A specification should be written.• DAC noise not needed (given resolution and Shot noise)

Data Rates, Online Computing Needs

30 Mbytes/sec total = 10x Qweak rate

Need >1 Gbit/sec network, ~1000 Terabytes of tape (MSS), and 20 Tbyte staging disk.

50 cpu farm to handle online tasks

• Real-time helicity-correlated feedback

• Online checks of data quality

• Prompt analysis of 100% of data with full corrections

R. Michaels, MOLLER Meeting, Aug, 2015

Present Status of Parity DAQin Hall A

Crate in Counting Room is working good for beamline checkout, but no signals plugged in

Two Qweak ADCs were added (thanks Rakitha Beminiwattha)together with HAPPEX ADCs, scalers, and I/O

Plan to revive Injector Crate (Qweak) – by ~November

R. Michaels, MOLLER Meeting, Aug, 2015

Testing Qweak ADCs with a few-volt ramping function AD

C v

alue

Event #

glitch

A Fast Counting-Mode DAQ for Compton, but a precursor for MOLLER needs.

VETROC

VETROC

CTP(FPGA)

Logi

c s

igna

ls (

128)

Trigger

JLab FADC

Integrate

threshold

AD

C

chan

nel

Sample number

Deployed in Hall A plan is to commission it this Fall if we have opportunity

Based on JLab FADC together with scalers and I/O.

VETROC -- pipelining TDC (s) whose hits form trigger in a CTP (readout at >200 kHz, trigger formed at ~1 MHz) -- VETROC under test by Scott Barcus (W&M student; advisor Todd Averett)

+ Bryan Moffit and Ben Raydo

Conclusions -- MOLLER DAQ

(thanks, Paul King, for valuable inputs)

• Extrapolating from successful DAQ experience from JLAB PV Experiments

• Need integrating DAQ, counting DAQ, and small test stands

• Excellent Qweak ADCs and I-to-V are good baseline designs, need an updated specification and a plan (new components, engineering support, procurement strategy)

• Data rates ~10x Qweak: Looks manageable with anticipated hardware (VME, network, multicore PCs, tapes), but need to keep up with 100% prompt analysis

`

R. Michaels, MOLLER Meeting, Aug, 2015