disk

WP-4 “Information Technology”

J. Hogenbirk/M. de Jong

Introduction (‘Antares biased’) Design considerations Recent developments Summary

“All-data-to-shore”

photondetection

informationtransmission information

management

informationdistribution

detector

f m

f 1

ff

m+1

m minimum number of

time-position correlated photons

“All-data-to-shore” *

Scientifically– maximise neutrino detection efficiency– maintain flexibility (also after construction)– enable different physics (e.g. Magnetic Monopole)

Technically– reduce data transmission to a linear problem (scalability)– locate all complexity on shore (reliability)– optimisation of data filter (quality)

* Maximum of event related data

Status Antares

• established proof-of-principle of “All-data-to-shore” • excellent time resolution → easy to find tracks• access to L0 data (single photons), see next pages• easy to include external triggers, see next pages

NEMO• mini tower operational• readout also based on “All-data-to-shore”

Nestor• readout for 4-floor NESTOR tower ready, NuBE• evaluation of commercial digitization system

completed

+ L0● L1

shower

Cherenkovcone

muon

neutrino

location of GRB

detector

All data before, during and after

GRB

alert

save

analysis

Gamma-Ray Burst

All data

TCP/IP

TCP/IP

GRB time – earliest recorded raw data

delay [s]

num

ber

of g

am

ma

-ra

y b

urs

ts

Access to data before GRB delayed messages

Design considerations

Functional geography

Photon detection– High data rate– Uni-directional– Low information density– Timing ~ns

Instrumentation– Low data rate– Bi-directional– High information density– Timing ~ms

separation of functionalities

Separation of functionalities

Optimise implementation Reduce cost Parallel design/production * Reliability versus redundancy

Detection Units Instrumentation Units

requires proof of concept for calibration

*Critical path relaxation

Photon counting

Large detection area PMT– Slow– Analogue– Q-integrator– ADC

Small detection area PMT– Fast– Digital– single photon counting– Time-over-threshold

two-photon purityphoton is digital!

Probability to detect 2 (or more) photons

as a function of

photo-cathode area distance between muon and PMT

wavefront

Cherenkov light cone

0

/ sin

( )2

cabsReR I

R

~1 km

1-2 abs

R [m]

P(#

≥

2)

– 0.01 m2

– 0.02 m2

– 0.03 m2

– 0.04 m2

– 0.05 m2

Probability to detect 2 (or more) photons

QE = 25%photo-cathode area:

2 x larger PMT does NOT see twice as far

Time stamping

Off-shore TDC– Distributed clock system

• Master clock• Time calibration• Network• Many slave clocks

– “Store and Forward” readout

On-shore TDC– Local clock system

• Master clock• Time calibration• ‘smart’ TDCs

– “Real-time” readout• Software (protocol)• Hardware (‘analogue’)

minimise off-shore electronics

Time slice(or “how-to-get-all-data-in-one-

place”)

/T L n c

time muon takes to traverse detector

~

Trigger Trigger Trigger

time

Ethernet switch

off-shore

on shore

Trigger Trigger Trigger

time

Ethernet switch

off-shore

on shore

Trigger Trigger Trigger

time

Ethernet switch

off-shore

on shore

Design concepts

à la Antares 1-1 mixed: copper riser / fibre backbone photonics based

à la Antares

Design of new front-end chip (Guilloux, Delagnes, Druillole) Design of new FPGA/CPU (Herve, Shebli, Louis) Design of data transmission (Jelle, Henk, Mar) New clock (?) New slow control (Michel) Network optimisation

– copper/fibre (Louis, Henk, ?)– Ethernet switch (Louis)

Both slow control & data acquisition (mjg)

1-1 mixed: copper riser / fibre backbone

Design of multi-functional FPGA system– FPGA/CPU integration (Herve, Shebli)– Slow control (Michel?)– Front end (Guilloux, Delagnes, Druillole)

Integration of clock & data transmission system– Time synchronisation & calibration (Rethore, Herve, Henk)– Hardware/software (Nemo)

Network optimisation (Jelle, Nemo?, ?)

Photonics based

Design of front-end electronics-photonics (Sander, Jelle, Mar) Optical network (Jelle, Mar) On-shore multi-laser Mar, Jean Jennen) Synchronised readout (mjg) On-shore smart TDC (Saclay, Hervé) No slow control (WP2)

Per 16-04-2007 new partners show interest to participate after an upcoming dedicated meeting of WP4

Review presentations WP4 parallel session

1. NEMO phase 1: Clock distribution

2. NEMO floor control Module

3. Progress on DAQ physical layer

4. Progress on optical components

5. Commercial Digitizing card

Conclusions Nemo phase 1: clock distribution

• Currently working for 4 floors

• NEMO phase 2: clock distribution to 16 floors

• Setup can be easily adapted to serve a KM3NeT size apparatus

Conclusions by the WP4 meeting participants

1.Weakness: lack of input from other WP’s

2.Dedicated WP4 meeting is wanted

with inputs from other WP’s

3.Use today’s technology is required

4.Get together to:

define a medium scale demonstrator

roadmap to efficient decision making on technology

General summary “All-data-to-shore” is shown to work

– reduce off-shore electronics to minimum

Communication with other WP’s important– separation of functionalities– front-end electronics

Pursue different concepts– à la Antares– 1-1 mixed: copper riser / fibre backbone– photonics based