Tables and figures for the PRR Calibration and tests
Preamble
This document refers to the test and calibration activities that must be carried out for the correct functioning of the telescope.
The document is divided into two main sessions named hereafter: Detector Calibration and Active Medium calibration.
The first (Detector Calibration) refers to all the instruments and procedures needed to calibrate the apparatus including:
 D1- Number of photons detected;
 D2- Timing (absolute and relative);
 D3- Positioning of the structure (absolute and relative).
The latter (Active Medium Calibration) to calibration of the active medium (i.e. seawater) including mainly:
 M1- Light propagation properties;
 M2- Sound propagation properties;
 M3 – Water column oceanographic properties
Each calibration issue is demanded to several subsystems, instruments and procedures to ensure cross-calibration and adequate redundancy and complementarity of data.
Accuracy of the measurement add it
Power consumption and other details of instrumentation
Summary tables of calibration systems and tests
Parameter
System
Subsystem
D1- Number
of photons
DOM
PMT
On-shore calibration
method
Black Box: PMT + resistive base
aim: production test- about 1% of all
PMTs
Onshore calibration
parameters
Gain @Nominal HV,After/pre
pulses, Dark Current
(To be stored on DB)
Off-shore Calibration
method
Off-shore Calibration
parameters
40K
PMT nominal/actual HV
PMT actual gain
Gain at Nominal Voltage 3E6
H=dLogG/dLogHV -> 6.5<H<8
Optional measurements
QE, CE
PMT+digital base
Black box: PMT+ base
aim:. PMT+base acceptance and
calibration,
CLB / octopus independent
measurements
Gain Slope, Gain at Nominal HV
Dark Counts @NHV
ToT vs. charge @NHV,
TTS @ NHV
After/pre pulses @NHV
(To be stored on DB)
PMT assembly acceptance
characteristics (see tender):
- Functionality
- Dark Current @NHV and 0.3
spe: <2 kHz
- Spurious @ NHV
pre-pulses <1%
delayed pulses <3.5 %
afterpulses 1 (early) < 2%
afterpulses 2 (late) < 10%
Full DOM
Red Box (31 light sources): DOM
aim: DOM acceptance and calibration
PMT Mapping
DC @ NHV
After/pre pulses @NHV
Charge spectrum @ NHV
(To be stored on DB)
charge spectrum per PMT
DOM acceptance characteristics:
# PMTs within specs > 27
D2- Timing
DOM
PMT
Full DOM
(PMT-Base, Octopus,
CLB)
Black Box: PMT + resistive base
aim: production test- about 1% of all
PMTs
Red Box (31 light sources and GPS):
DOM
aim: DOM acceptance and calibration
TTS, TT
(To be stored on DB)
40K
coincidence spectrum on
PMTs (inter DOM)
PMT assembly acceptance
characteristics (see tender):
- TTS < 5 ns
- TT < 7 ns
vertical tracks (intra DU)
ToT@ NHV
Time Offset (delta t) @NHV
(DOM-PMT table to be stored on
DB)
laser beacon coincidence
(inter DU, intra DOM)
nano-beacon coincidence
(intra DOM, intra DU)
horizontal tracks (inter DU)
DOM acceptance characteristics:
# PMTs within specs > 27
nano-beacon
Factory Test: nano beacon
aim: nano beacon acceptance and
calibration
Red Box: DOM
aim: nano beacon functionality test
and
Data
Transmission
Optical Fibers +
electronics latencies
(DU+network)
DU
Shore Station
CB
D3
Positioning
(timing
issues
demanded
to D2)
DOM
White Rabbit.
DU base: same fibre for TX and RX
Light emission time distribution,
time delay @ peak (latency)
Nano beacon acceptance defined
in the tender
Time delay of nano beacon pulse
in close PMT
In prototypes check latency vs.
long time and switch on/off
operation
T < X ns
To be defined wit the electronics
and optical network group
Dark room (GPS + calibrated fibres
on 1 PMT per DOM): Line
aim: Line acceptance test and time
calibration with reference PMT
Time delay between reference
PMTs in different DOMs.
GPS
Electronics Crate
White Rabbit Switch
Laser Beacon
DU base: same fibre for TX and RX
To be defined wit the electronics
and optical network group
Piezo sensor + AES
board
Factory Test: piezo+ AES interface
board
aim: piezo + board acceptance and
pre-calibration
Factory Test: laser beacon
aim: nano beacon acceptance and
calibration
Frequency and amplitude
response (Factory sheet, to be
stored on DB)
Equivalent noise
Piezo acceptance defined in the
tender
(Factory sheet)
Special DU
Base (for the
Piezo sensitivity: Beacon
signal amplitude and
frequency .
Piezo nominal/actual sensitivity and noise
spectrum
DU movements vs. currents
Full DOM
Red Box (Acoustic source): DOM
aim: DOM acceptance
Frequency and amplitude
response (functionality test)
Equivalent noise
(to be stored on DB)
AHRS (Compass, tilt,
accelerometer)
Factory Test: AHRS
aim: AHRS acceptance and precalibration
AHRS calibration parameters
(Factory sheet)
Muon tracks
Laser beacons, nano beacons
AHRS nominal/actual calibration parameters
Red Box (Rotating dish): DOM
aim: DOM acceptance and calibration
AHRS calibration parameters
with all DOM on (to be stored on
DB)
Frequency and amplitude
response (Factory sheet, to be
Beacon signal amplitude and
frequency
Hydro nominal/actual sensitivity and noise
spectrum
Hydrophone
Factory Test: Digital Hydro
aim: digital hydro acceptance test and
fist strings)
CB (autocalibrating
LBL)
Autonomous
LBL
calibration
Hydrophone
Factory Test: Digital Hydro
aim: digital hydro acceptance test and
calibration
Beacon
Factory Test: Beacon
aim: acceptance test
Autonomous Beacons
Factory Test: Beacon
aim: acceptance test
stored on DB)
Equivalent noise (Factory sheet)
Frequency and amplitude
response (Factory sheet, to be
stored on DB)
Equivalent noise (Factory sheet)
Frequency and amplitude
response (Factory sheet, to be
stored on DB)
Beacon signal amplitude and
frequency
Hydro nominal/actual sensitivity and noise
spectrum
Frequency and amplitude
response (Factory sheet, to be
stored on DB)
PMT: Photomultiplier tube
DOM : Digital optical Module
LBL : Long Base-Line
AHRS: Compass/tilt/accelerometer board
DU: Detection Unit
CB: Calibration Base
CU: Calibration Unit
GPS: Global Positioning System (here GPS receiver)
Red Box: Calibration box for the DOM equipped with:
GPS (necessary for the DOM test)
31 light sources (synchronised by GPS)
acoustic source + signal generator (Synchronised by GPS)
signal generator (synchronised by GPS)
rotating dish
Black Box: Calibration Box for PMTs and bases equipped with:
Custom DAQ system or customised CLB DAQ
Diffuse light source
Dark Room: Calibration Room for all DOMs
Single light source GPS driven and 18 Fibres (same length) distributed to 1 PMT/DOM
Parameter
System
Subsystem
M1- Light
propagation
properties
DOM
Nano beacon
On-shore calibration
method
Factory Test: nano beacon
aim: nano beacon acceptance
and calibration
Onshore calibration
parameters
Light emission time spectrum, time delay
@ peak
Off-shore Calibration
method
Off-shore Calibration
parameters
Red Box: DOM
aim: nano beacon functionality
test and
M2-Sound
Propagation
properties
CB
Laser Beacon
CU
CTD
Factory Test: Laser Beacon
aim: laser beacon acceptance
Factory Test: CTD
aim: CTD acceptance
Light emission time spectrum, time delay
@ peak
Dependent on CTD model
Calibration constants for measured
quantities (P,T,C) and derived ones
(Depth, Sound Velocity, Salinity,…)
Inter-calibration with other instruments
M3- Water
column
oceanograp
hic
properties
CU
SVP
Factory Test: SVP
aim: SVP acceptance
Dependent on SVP model
Inter-calibration with other instruments
CTD
Factory Test: CTD
aim: SVP acceptance
Factory Test: ADCP
aim: SVP acceptance
Dependent on CTD model
Inter-calibration with other instruments
Dependent on CTD model
Inter-calibration with other instruments
ADCP
Description of the work
PMT batch qualification (1%) of the production – To be discussed and confirmed with the PMT Calibration group
Black box
Material
plug and play PMT bases (ECAP like)
Light source
12 channels DAQ
Measurements:
Gain Slope, Gain @Nominal HV,After/pre pulses, QE, CE , Dark Current
(To be stored on DB)
Details:
The base circuit is mechanically coupled with a plastic support
The base has PIN receptacles is connects the leads to the circuit
Leads inserted into the holes and into pins – if PMT leads are straight the time for the integration is 30 sec.
Dark adaptation for PMTs 12 h.
PMT and active base acceptance test and calibration
This procedure is studied under the following assumptions
Logistics:
A) 15000 PMTs will arrive from Hamamatsu to INFN-LNS and Catania
B) 7500 PMT will be sent to ECAP and 7500 PMTs will be sent to INFN-Naples. Both ECAP and INFN-Naples will also receive 7500 bases (per site) from NIKHEF
C) INFN-Naples and ECAP will perform soldering of bases into PMTs and tests and Calibration of the PMT+base assembly
D) PMTs assemblies will be distributed to DOM assembly sites (Naples, Nikhef, ECAP, Catania-LNS, ….) for DOM integration, test and Calibration
Sites:
INFN Napoli
Man Power:
INFN Napoli , LNS and Catania
Time Plan:
Soldering + coating
15 min per PMT  1875 h  8 h/day 234 working days.  20 day/month  11.7 month/man  4 operators  3 months
Testing and calibration
7500 PMT + base  31 PMT per test in a dark box  242 test runs  4 tests/ day  61 days (2 dark boxes per site?)
Instrumentation: Black box
Mechanical Frame
€ 4.000
Laser source (available at INFN Naples and Catania)
€ 15.000
Optical splitter 1x32 : 31 PMT + power meter
€ 10.000
Improved Optical Power Meter (fibre monitor)
€ 5.000
Optical attenuator set (on main fibre, available at Naples) € 1.500
31 optical diffusers on FC/PC
€
500
UPS for the laser source
€ 1.500
PMT+base digital readout 31 channels: 1 simplified shore station , 1 CLB , 2 octopus
Measurements and time details:
Gain Slope, Gain at Nominal HV, Dark Counts @NHV, TTS @ NHV, ToT vs. charge @NHV, After/pre pulses @NHV, (To be stored on DB)
PMT unpacking and dark box filling
Dark box closing and pre-setting
Functioning test of the chain
Dark adaption PMT
HV on – Set Gain (PMT on at Nominal HV, Hamamatsu 3E6)
Measurement A:
Dark Current Rate
Measurement B:
Laser and absorbers set to spe (Laser rate 20 kHz)
Measurement B1:
ToT @ NHV
Measurement B2
TTS @ NHV
Measurement B3:
Spurious Pulses (pre-pulses, delayed pulses, after pulses 1, after pulses 2)
Measurement C:
Gain Slope (ToT at 3 different HV: NHV, NHV+10%, NHV-10%)
(varying optical attenuators and not the laser intensity!)
PMT re-packing and dark box unfilling
Total
Data Base filling
DOM acceptance and calibration
Sites:
INFN Napoli , INFN Catania, ECAP, Nikhef, others
Man Power:
All sites
Time Plan:
DOM Assembly with all pre-qualified probes
See PRR DOM time plan
Testing and calibration
15000 PMTs / 31 (PMT/DOM) in 4 sites = 121 DOMs per site  6 months (20 days/month)
Instrumentation: Red Box
Mechanical Frame
Laser source (available at INFN Naples and Catania)
Optical splitter 1x4 : 5 PMT + 1 power meter
Improved Optical Power Meter (fibre monitor)
UPS for the laser source
1 full shore station
€ 4.000
€ 15.000
€ 3.000
€ 5.000
€ 1.500
2 min x 31 PMTs =
1h
15 min
15 min
8h
1h
1 min
5 min
10 min
2 min x 31 PMTs =
1h
12 h (8 h dark adaption!)
2h
GPS receiver
acoustic emitter, signal generator (GPS-PPS trigger)
rotating dish + reference
€ 2.000
€ 2.000
Measurements and time details:
DOM integration
Gel solidification
12 h
12 h
Red box closing and pre-setting
30 min
Functioning test of the DOM
30 min
Dark adaption PMT
8h
HV on – Set Gain (PMT on at Nominal HV, Hamamatsu 3E6)
1h
Measurement A:
Dark Current Rate (with glass and gel)
1 min
Measurement B:
Laser and absorbers set to spe (Laser rate 20 kHz) – Laser trigger GPS clock/PPS
10 min
Measurement B1:
mapping : only 4 fibers on PMTs, use 40K to inter-calibrate PMTs (see http://pi1222.physik.uni-erlangen.de/Qualification/24)
Measurement B2:
delta T @ NHV (laser with 4 fibers firing 4 PMTs the rest )
Measurement B3:
ToT @ NHV
Measurement B4
TTS @ NHV
Measurement B5:
Spurious Pulses (pre-pulses, delayed pulses, after pulses 1, after pulses 2)
Measurement C:
Measurement D:
Measurement E:
DOM Packing
Total
Data Base filling
Functionality test of acoustic reception (20,30,40 kHz, 2 amplitudes, acoustic emitter trigger GPS-PPS)
Compass Calibration using rotating dish
Functionality test of nano beacon
5 min
15 min
10 min
20 min
1 h + 24 h + 8 h dark adaption
2h
DU acceptance and calibration
Dark room:
Materials
laser light source
optical splitter 1 x 18
full shore station
GPS
Acoustic emitter for piezo test
Calibrated fibers at the DU base
Measurements:
1 PMT per DU (intra DOM synchronisation): ToT@ NHV, Time Offset @NHV
nano Beacon: time delay @ peak with close PMTs
Piezoelectric sensor: functionality test
Details:
Time for DU assembly – see DU integration document
Dark adaptation for PMTs <12 h
Time for measurements 1 h (including 5’ for the piezo and 5’ for the nano-beacon)
Calibration Units
3 CTD (top, middle, bottom) + oxygen (TBD)
2 SVP (top, bottom)
2 ADCP (top, bottom)
FIGURE 4 :
Cui :
Cub :
Inductive cable
Inductive interface
coupled to
standard RS232
instrument
Base container :
Inductive
instrument
ICC
- Sound Electronic Board
- CLBV2
Extra container :
+ others (AC/DC DC/DC ….)
- IMM
- batteries
Acoustic
releases
Interlink :
Ethernet electric
cable
Laser
Acoustic Acoustic
- detector clock (FO)
Receiver Emitter
- data transfer (FO)
- energy
DU or
Dead weight
Calibration Bases
Laser Beacon, acoustic beacon, acoustic receiver (CLB)
JB
Implementation plan Capo Passero
Calibration Bases (or DU + active bases) # 18, 22, 29
IU: attached via ROV mate electrical connector to DU 29 (at about 80 m distance)
DU 9-12 should have acoustic receivers at their base
Autonomous Beacons: for the first lines should be placed in positions 18, 22 and later 29, 32
In addition:
Towers will all have active bases (hydrophones + acoustic emitter)
Towers 6 and 4 will have Laser Beacon at the base
Towers 1,2,3 will have CTD, SVPs and DCS
Implementation plan Meust
Calibration Bases (or DU + active bases) Define if numbering follows the installation sequence
IU: attached via ROV mate electrical connector to CB
First DUs should have acoustic receivers at their base
Autonomous Beacons: for the first lines should be placed in positions TBD