1. Pre-Production Models for KM3NeT
Els de Wolf
Nikhef/UvA-GRAPPA
KM3NeT General Meeting
30 March 2011, Amsterdam

2. Deliverables of WPF/L
1. Description of Pre-Production Models (PPMs) for
a detection unit
a calibration system
a data acquisition system
published in December 2010
‘Technical description of the PPM of the KM3NeT detection unit’
(KM3NeT_FL_REP_PPM_Description)
2. Realised and tested “small-scale” PPMs
3. Description of Production Model of KM3NeT

3. Recent History December 2010: PPM-report sent to EC
January 2011: SPB gave priority to development of
multi-PMT DOM as optical sensor
DOMBAR as storey configuration
DOMBAR = “BAR with a DOM at either end”
Technology choice based on comparison (of various designs) w.r.t:
Physics performance for full KM3NeT detector
Obtained validation results
Feasibility of assembly/integration during production
Reliability estimates
Failure mode analysis
Cost for full KM3NeT detector

4. PPM-Objectives Provide answers on the following questions:
Can we deploy a detection unit?  in-situ test mandatory
Can we measure signals?
Can we calibrate?
Can we get these signals to shore? connection mandatory
Can we measure muon signals?
What do we learn for the Production Model for KM3NeT?  results from in-situ and in-lab tests

5. Hosting infrastructure
PPM DU description
2 connected
storeys
Backbone
2 DOMS
2 hydrophones
Digital Optical Module
31 PMTs
FE electronics
Power board
Central logic board
Nanobeacon
Acoustic piezo
Compass/tilt metre
2 DOMS
2 hydrophones 18
Autonomous
dummy
storeys
2 spheres
1 NDLM :
Optic. Fanout Module :
NDLM
Pressure
Compass
3D accelerometer
2 spheres
1 NDLM
2 spacers
1 NDLM
1 NDLM
Base + deadweight
Hosting infrastructure

6. Can we deploy a detection unit?
To be realised:
The deployment of full mechanical DU-model with vertical e/o backbone cable
To be learned:
Does it unfurl correctly to its full length?
Is the hydrodynamic behaviour as predicted?
Does the vertical e/o backbone cable remain undamaged?
Are there no leaks?
Is there not serious other damage?

7. Can we measure signals? To be realised: To be learned: PMTs in DOMs
Readout electronics: FE, central logic
To be learned:
Test of readout electronics
Singles rates
Coincidence rates
Gain stability
PMT identification

8. Can we calibrate? To be realised: To be learned:
Acoustic piezo sensors in DOM (position)
Hydrophones at 2 storeys (position) (redundancy)
LBL acoustic transmitter in seafloor infrastructure
Nanobeacons in DOMs (timing)
Stand-alone sensors
Point-to-point data transmission network (timing)
Available: 40K
To be learned:
Accuracy of positioning
Comparison hydrophone + piezo sensor
Electronics resolution
Timing resolution
Amplitude resolution

9. Can we get signals to shore?
To be realised:
Data transmission network
DAQ electronics and logic
To be learned:
BER (bit error rate)
Optical budget
DAQ stability and logic

10. Can we measure muon signals?
To be realised:
2 storeys with 4 DOMs
Trigger: 4 DOMs hit  4 parameters
To be learned:
Depth dependence of coincidences
Theta dependence of coincidences
Phi dependence of coincidences

11. What do we learn for the Production Model for KM3NeT?
To be realised:
Evaluation of PPM results
Evaluation of assembly/integration procedures
Evaluation of QA/QC procedures
Results from failure rate analyses
To be learned:
Feasibility of design for KM3NeT
Are there non-conformities?
Is the design OK?
If it is OK, what needs to be optimised for mass production/mass deployment?
Which QA/QC procedures should be implemented?
To be delivered:
Description of Production Model for KM3NeT

12. Hosting infrastructure
PPM DU description
2 connected
storeys 18
Autonomous
dummy
2 spacers
Backbone
Base + deadweight
2 DOMS
2 hydrophones
2 spheres
1 NDLM
Optic. Fanout Module :
Status reports of details follow now:
PMTs
Instrumentation
Readout/DAQ
Deployments
DOMBAR design
Seafloor infrastructure
Deployment vessels, ROVs
Hosting infrastructure