GOALS of meeting …
•
Discuss status of available detector arrays
•
Discuss current developments (both here and elsewhere –
DESPEC, …)
•
Identify technical “know-how” in different labs
•
Identify and define possible collaborations (FP7 ??)
•
Define goals, contributions, timelines, …
NAO – Réunion 02/07
Jean-Luc Lecouey, Seminar
Programme …
•
Introduction + Goals, ideas, etc for a new array - Nigel Orr
•
Status of DESPEC neutron detector array work - Daniel Cano Ott
•
Two-neutron detection with TONNERRE - Miguel Marqués
•
Simulations using GEANT4 & MENATE - Brian Roeder
•
Status of the Neutromania project - Franck Delaunay
•
Digital electronics developments at LPC - David Etasse
•
Neutron detection at Bruyeres le Chatel - Xavier Ledoux
•
Discussion of how to go forward, interests and possible
contributions from different labs, test experiments, etc
NAO – Réunion 02/07
Jean-Luc Lecouey, Seminar
A New Low-Energy* Neutron Detector for the
GANIL-SPIRAL-2 Community ?
•
Available detector arrays + status
•
Current developments
•
TONNERRE
•
Future low-energy/b-xn array
* b-xn, (d,n), (p,n), - direct reactions not addressed today but
requirements very similar
NAO – Réunion 02/07
Jean-Luc Lecouey, Seminar
Neutron Detector Arrays Available within
the French* GANIL-Based Community
•
DEMON : ~96 liquid scintillator modules (LPC, IRéS, UCL, ULB)
•
EDEN : ~40 liquid scintillator modules
(IPNO)
ToF  En , granularity  q, Q  n-g discrimination
number of hits x e x ds/dW  Mn
•
TONNERRE : ~32 Plastic scintillator bars
(LPC, Bucarest)
ToF  En, granularity + Dt  q
•
ORION : large volume Gd-doped liquid scintillator
* see also presentation by Xavier L. later today
Jean-Luc Lecouey, Seminar
STATUS of Neutron Detector Arrays Available within
the French GANIL-Based Community
•
DEMON : majority of modules still in reasonable condition
VXI + Daq no longer serviceable

•
EDEN :
future unclear
majority of modules still in good condition
CAMAC limited lifetime, coupling with new Daq’s
problematic

•
future unclear
TONNERRE : upgraded 16 modules/32 PMTs
VXI + GANIL-LPC Daq, VME under implementation

•
available but not well adapted to future facilities
ORION : “moth balled”
Jean-Luc Lecouey, Seminar
Current Developments within the French
GANIL-Based Community
•
New generation (solid) scintillators
 ANR : L. Stuttgé et al. (Strasbourg-Caen)
see contribution by Franck D.
•
New generation electronics-DAQ
 digital daq : D. Etasse et al. (LPC)
[manpower – BDI requested]
see contribution by David E.
•
Exploratory studies/simulations & prototype expts (~2007-2008)
 EURISOL + SPIRAL-2 (LPC) : breakup arrays + b-n, b-n-n …
see contributions by Brian R. & Miguel M.
Jean-Luc Lecouey, Seminar
TONNERRE Array
• Up to 32 plastic scintillators [BC400, 160 x 20 x 4 cm, d=1.2 m]
• En by TOF : 200 keV < En < ~5 MeV
• DW  45% of 4p
• dE (1 MeV): ~ 80 keV
•
e (1 MeV) ~ 50 %
TONNERRE
EXOGAM
scintillators
A. Buta et al., NIM A455 (2000) 412
Jean-Luc Lecouey, Seminar
TONNERRE : Detection Efficiency
A. Buta et al., NIM A455 (2000) 412
Jean-Luc Lecouey, Seminar
TONNERRE @ ISOLDE : State-of-the-Art
F Perrot et al., PRC74 (2006)
Jean-Luc Lecouey, Seminar
TONNERRE : Limitations …
Neutron time-of-flight spectra : b-decay of 45Cl28 and
46Cl
29
2000
45Cl
46
46Cl
Cl29
28
number of counts
number of counts
4000
28
1000
2000
800
1500
600
1000
400
500
0
200
50
100
150
200
time-of-flight (ns)
250
300
0
50
100
150
200
time-of-flight (ns)
250
300
S. Grévy and the TONNERRE collaboration
Jean-Luc Lecouey, Seminar
b-Delayed Neutron Detection :
“Ground Rules” for a Future Detector
•n-g discrimination  reduce backgrounds, enable b-2n,3n ... detection

Liquid scintillators (or new solid scintillators)
•improve dEn and eliminate “tails” in TOF spectra

thin, small volume detectors with increased dflight
•lowest possible threshold in En

thin, small volume detectors + digital electronics
•cross-talk rejection  enable b-2n, 3n … detection

modular, highly granular array + variable geometry
•high eg  identification of n-decay to excited states

large volume high efficiency Ge det’s (segmented ??)
(conflict with need for high DWn)
Jean-Luc Lecouey, Seminar