1. “n @ BTF”… Study and Design of an experiment at the DAFNE BTF for neutron Photo-production
S. Bartalucci, R. Bedogni , B. Buonomo, A. Esposito , G. Mazzitelli, L. Quintieri
Technical support of FISA, Acc. Div. And Res. Div. of LNF
G. Mazzitelli – CSN5, Ferrara 17 Sep 2008

2. G. Mazzitelli – CSN5, Ferrara 17 Sep 2008
The DAFNE BTF
BTF
high current Linac:
mA e- 200 mA e+,
ns pulses, at least 107 particles
The BTF is a e-/e+ test-beam facility in the Frascati DAFNE collider complex
Need to attenuate the primary beam:
Single particle regime is ideal for detector testing purposes
Allows to tune the beam intensity
Allows to tune the beam energy
G. Mazzitelli – CSN5, Ferrara 17 Sep 2008

3. G. Mazzitelli – CSN5, Ferrara 17 Sep 2008
BTF layout
BTF Hall
4 m
5.5 m
Hall
control
room
LINAC
tunnel
momentum analyzer
main ring
G. Mazzitelli – CSN5, Ferrara 17 Sep 2008

4. LINAC beam attenuation
Selected energy (MeV)
N. of particles
detector
1e-
2e-
3e-
103
102 10 1
W slits
LINAC Beam mA
100
300
500
450 magnet
tunable Cu target:
1.7, 2.0, 2.3 X0
G. Mazzitelli – CSN5, Ferrara 17 Sep 2008

5. BTF beam characteristic
Beam (e- or e+) intensity can be adjusted by means of the energy dispersion and collimators, down to single particle per pulses
Number (particles/pulse) 1105 11010
Energy (MeV) 750
Repetition rate (Hz)
Pulse Duration (ns) or 10
p resolution 1%
Spot size (mm) sx,y ≈ 2 (single particle) up to 10*10 (high multiplicity)
Divergence (mmrad) s’x,y ≈ 2 (single particle) up to 10 (high multiplicity)
Multi-purpose facility:
H.E. detector calibration and setup
Low energy calorimetry & resolution
Low energy electromagnetic interaction studies
High multiplicity efficiency
Detectors aging and efficiency
Beam diagnostics
G. Mazzitelli – CSN5, Ferrara 17 Sep 2008

6. G. Mazzitelli – CSN5, Ferrara 17 Sep 2008
Motivation
General interest of BTF scientific community for the neutron production at BTF
Possibility to test detector diagnostic at low neutron flux and low energy
Generation of the knowhow needed for next generation of high energy source (see FEL)
Possibility to have a new European facility in ISO standard
G. Mazzitelli – CSN5, Ferrara 17 Sep 2008

7. Study of optimized target: lead TGT sphere R=12X0
Up to 100 MeV the spectrum is described as a Maxwellian distribution with average around 1 MeV
Approaching the higher energies the Quasi-Deuteron Effects adds a tail of high-energy neutrons to the Giant resonance spectrum. The slope becomes stepper as the incident electron energy is approached
Monte Carlo simulation ( by Fluka code)
Fluka result: neutron/primary
G. Mazzitelli – CSN5, Ferrara 17 Sep 2008

8. G. Mazzitelli – CSN5, Ferrara 17 Sep 2008
Experimental Set-up
BTF Experimental Hall
Taget with multiple
beam extraction lines
(MC model)
e- beam
neutron exit
at different angle
Transfer Line
G. Mazzitelli – CSN5, Ferrara 17 Sep 2008

9. High lights and support LNF Facility
LNF is ideal site for testing neutron photo-production:
BTF is the only European facility running with high electron intensity at low energy
The energy limitation of the BTF allows to investigate a neutron production energy rage of interest for many purpose, that will not be overlapped with the next high intensity future facility
Acc. Div. Technical support for operation and setup
The service support
Accelerator Division (mechanical design, alignment, etc)
FISA (FIsica SAnitaria)
Research Division (electronics, machinery, etc)
G. Mazzitelli – CSN5, Ferrara 17 Sep 2008

10. G. Mazzitelli – CSN5, Ferrara 17 Sep 2008
Conclusion
Neutron Detectors R&D for very precise Spectra measurement in high energy electron accelerators
R&D experiment to study the neutronic photoproduction source in order to acquire the necessary KNOW-HOW for future application with high intensity source (for medical and industrial applications)
build an European INFN facility that allows the study and calibration of detectors and instrumentations for high energy neutrons with application in nuclear physics, dosimetry and radioprotection
investigate the feasibility of a could neutron source (with energy less than 1eV). This kind of source has a great interest both in fundamental physics and for applications in nano-technologies
G. Mazzitelli – CSN5, Ferrara 17 Sep 2008

11. G. Mazzitelli – CSN5, Ferrara 17 Sep 2008
Work done e to be done
Preliminary Monte Carlo Simulations to estimate the source term and neutron spectra; Definition of the optimized Target and of extraction lines (done)
Individuate different working configurations (using different moderating material layers) to reproduce different neutron spectra (in progress);
Individuate a configuration for having monochromatic cold neutron beams (i.e with energy < 1eV) (estimation of the neutron rate)
Target + Shield + Support final DESIGN and construction
The techniques needed for the determination of the neutron spectra from thermal to GeV neutrons are already known and consolidated (Bonner Spheres, activtion foils,nuclear track detectors....)
G. Mazzitelli – CSN5, Ferrara 17 Sep 2008

12. Richieste 1.8 fte Primo Anno Voce Costo kEuro
G. Mazzitelli (responsible), S.Bartalucci, B.Buonono (art.23), R. Bedogni (art.23), A.Esposito, L.Quintieri (art.23)
1.8 fte
Primo Anno
Voce
Costo kEuro
realizzazione bersaglio di Tungsteno
10/10 sub judice
Schermatura ottimizzata
22/22 sub judice
Meccanica per movimentazione
8/1
Diagnostica di base
5/0
Missioni Estere
8/2
Missioni Interne
4/1
Secondo Anno
Diagnostica Avanzata per quantametria di fascio 20
Elettronica 10
Consumo (gas,etc) 5 8 4
G. Mazzitelli – CSN5, Ferrara 17 Sep 2008