Status and perspectives of an RFQ based neutron facility in Italy

Enrico FagottiEnrico FagottiINFN – Legnaro National Laboratory

L. Antoniazzi, P. Colautti, M. Comunian, V. Conte, J. Esposito, F. Grespan, A. Palmieri, A. Pisent, C. Roncolato, C. Ceballos Sanchez

D. Moro, L. De Nardo

L. Evangelista, G. Sotti

O tli

Project overview

Outline

Project overview

BNCT application

High intensity accelerator statusHigh intensity accelerator statusProton source

Low energy beam transportLow energy beam transport

RFQ

Beryllium target and neutron beam shapingBeryllium target and neutron beam shapingassembly

Project overviewProject overviewAn accelerator-driven high intensity neutron source at INFN-LNL

RF distribution

Klystron

Operating room withepithermal neutronsource TRASCO

TRASCO‐RFQ 

TRIPS proton source

BNCT surgery with thermal  neutron source  SPES BNCT

High level waste irradiation

IFMIF

irradiation

Main parameters

Accelerator type: LINACP t t t 50 A

Main parameters

Proton current: up to 50 mAProton energy: 5 MeVTime structure: up to CW Beam power: up to 250 kWNeutron converter: BeOperative power density on Be target: 700 Watt/cm2Operative power density on Be target: 700 Watt/cmNeutron source intensity: 1014 s-1

Main application: BNCT

Boron Neutron Capture Therapy (BNCT)Boron Neutron Capture Therapy (BNCT)

Boron Neutron Capture Therapy (BNCT) is an experimental binaryradiotherapy which exploits the neutron capture reaction 10B(n α)7Liradiotherapy which exploits the neutron capture reaction B(n,α) Li induced by thermal neutrons (<E> = 25 meV).The α-particle and 7Li recoiling nucleus are high LET and short range (< mean cell diameter ≈ 10 μm) particles able to deposit their

d 10 d d

BPA

energy entirely inside the 10B loaded cell.

BSH

In this way the selectivity of BCNT depends on 10B distribution and not on the irradiation field

BPA BSH

In this way the selectivity of BCNT depends on 10B distribution and not on the irradiation field. This feature makes BNCT a valid option against the diffused tumorsAnother crucial aspect for the good outcome of the treatment in the availability of 10B carriersable to realize a selective delivery. The clinically approved molecules are BSH and BPA. Nowaday, the major challenge in BNCT research is the development ofmore dedicated carrieris.

BNCT at Pavia: the TAOrMINA method(Trattamento Avanzato d’Organi Mediante Irraggiamento Neutronico e g ggAutotrapianto)

The therapeutic concept is based on the irradiation of the isolated, previously 10BPA-infused organ in a neutron field where neutrons coming from all directions can irradiate the whole liverAf BPA i f i h li i I i h d d d h i fl d i di d i hAfter BPA infusion the liver is removed from the patient body

It is washed andput into 2 teflon bags

and then put into a tefloncontainer

and irradiated into the reactor

Two terminal patients affected with colon adenocarcinoma liver metastases were treated in Pavia with the TAOrMINAt eated Pav a w t t e T O M Nmethod between 2001 and 2003.In both cases, about 10 days after treatment the CT scanning evidenced the liver in normal condition while the adenocarcinomawmetastases appeared in a necrotic state.

High Intensity Accelerator Status

PSTATUS

Ip ≈ 45 mA

Proton source

p

E = 80 KeVεn,rms < 0.1 mm-mradφb(z = 200 mm) = 34 mmB ti t t CW

PS developed at LNS (2000)

Beam time structure: CW

NEAR FUTUREφb(z = 200 mm) = 10 mmφb( )[New extractor design] [LNL]

PS optimized at LNL with magnetic shielding (2007)

Beam time structure: CW & pulsed[Magnetron pulser] [LNL & DEE/UPV]

Low energy beam transportFast Emittance Scanner (FES): high resolution q-

Low energy beam transport

(FES): high resolution qq’ rms emittance in less than 2 seconds

LEBT developed at LNL

STATUSLEBT ready for assembly with solenoids, pumping system, non interceptive profile and current diagnostics, interceptive profiler and termination FC.

Solenoids developed at LNL

NEAR FUTURENeutralized transport optimization FGA development

Solenoids developed at LNLLEBT control system upgradee-trap construction

RFQ tRFQ: parametersParameter Value UnitEnergy In/Out 0.08/5.02 MeVFrequency 352 2 MHz

• 3 electromagnetic segments 2.4 meters long• 2 resonant coupling cells + dipole stabilizersFrequency 352.2 MHz

Proton Current (CW) 50 mAEmit. t. rms.n. in/out 0.20/0.21 mm-mradEmit. l. rms. 0.19 MeV-degRFQ length 7.13 m (8.4 λ)Intervane Voltage 68 KV (1.8 Kilp.)

• 2 resonant coupling cells + dipole stabilizers• each segment consists of two 1.2 meters long

modules (basic construction units)

g ( p )Transmission (Waterbag) 97.7 %Q0 (SuperFish) 10000Q0 (measured) 8100Beam Loading 0.148 MWRF Power dissipation 0.847 MW

C

Cooling Channel Q1 Q4

Braze JointA

B

Vacuum

Q1 Q4

Q3 Q2

D Port

RFQ f b i ti hi tRFQ: fabrication history...

... and some troubles

RFQ f b i ti l tRFQ: fabrication complete

RFQ t i2010. Low power RF measurements.- Field and frequency tuning with aluminum0.01

0.02

mpo

nents Quadrupole

Dipole1

Dipole2

RFQ: tuning

q y gcouplers

- Copper Tuners and Copper End Plates with RF contactsQ 8100 (SF 9900)

‐0.01

0

Perturba

tive field com Dipole2

- Q0=8100 (SF 9900)- Final High Power Coupler design (3D

HFSS simulations) and Coupler Production

‐0.020 0.5 1 1.5 2

z axis [m]

E.Fagotti

RFQ ill iRFQ: ancillaries

2010/2011. All Ancillaries for High Power Test ready and tested

High technology part (RFQ cavity, RF distribution, local cooling/tuning system local control system) was developedcooling/tuning system, local control system) was developed

Conventional installation (Klystron and conventional power supplies, secondary cooling system, building ) is required.

According to an agreement between INFN and CEA couplers andAccording to an agreement between INFN and CEA, couplers and RFQ are under high power test at Saclay.

RFQ RF l hi h t t

March 2011 10 kW couplers test

RFQ: RF coupler high power test

June 2011150 kW couplers test10 kW couplers test 150 kW couplers test

RF Amplifier

lay

CE

A S

acl

LNL

C l hi h l (1st J l d )Coupler high power test results (1st July update)

120000

140000

160000

Coupler conditioning at 2ms ‐ 100 ms

100

120

Coupler conditioning at CW

60000

80000

100000

Power ‐Watt

FWD‐1

FWD‐2

40

60

80

Power ‐kW

FWD‐1

FWD‐2

0

20000

40000

9:00 10:00 11:00 12:00 13:00 14:00 15:00 16:00 17:00 18:00

0

20

40

08:00 09:00 10:00 11:00 12:00 13:00 14:00 15:00 16:00 17:00 18:00 19:009:00 0:00 :00 :00 3:00 4:00 5:00 6:00 7:00 8:00

time

08:00 09:00 10:00 11:00 12:00 13:00 14:00 15:00 16:00 17:00 18:00 19:00

time

RFQ hi h t t

RFQ high power test stand is under construction.First test foreseen after summer

RFQ: high power test

First test foreseen after summer.

Milestones:• 1° Segment RFQ test→300 kW• Check of the water cooling/tuning system

Th B t t tThe Be proton-neutron converter

1. Be-tile brazed cooling pipes with Zr adapters 3. collector plates welding & EDM manufacturing process

2. Zr cooling system manifold & collector plates 4. Half target: final assembling ready for e-beam test

Th B t t t t ltThe Be target test result summary

Test type Test performed Main test results Test

passedyp p

passed

Thermal-mechanicalNumber of cycles: 2350

~ 10 times higher than requested(200)

• No any visible damage

• No cracks observed at metallographic analyses YES(200)

• Reliability better than expected

• Material hardening level half than expected

Radiation damage: neutron

Proper neutron fluence levels (1018-1020 cm-2)

• Mechanical properties not compromised even at higher dose levels (~0.1 dpa)

• He bubbles generation observed at higher d l l l ( 0 08 d )

YESdose levels only (~0.08 dpa)

• Lifetime estimation: 3100 hrs (doubled) with respect to design parameters (1600 hrs) =1yr

Radiation damage: proton Preparation of experimental set-up In progress

Th B Sh i A bl d liBe-9 thick target neutron spectra @ 4 MeV proton beam

1.4E+08In‐air beam port quality design requirements

The Beam Shaping Assembly modeling

1.0E+08

1.2E+08

roC

*sr)

]

0 degree Vol.1 7-ISCNT

0 deg.60 deg.

110 deg.135 deg.

148 deg.

n th (≤ 0.5 eV)   ≥  109 [cm‐2 s‐1]

n th /  n total ≥  0.90

‐Double‐differential neutron yielding spectra Be(p xn) at Ep=5MeV

‐ Proton beam distribution over the target

4.0E+07

6.0E+07

8.0E+07

Yiel

d [n

/(MeV

*mic

r

Dn epi+fast / n th ≤  2∙ 10‐13[Gy cm2]

D / n th ≤ 2∙ 10‐13[Gy cm2]

∙∙

B  P t‐Double‐differential neutron yielding spectra Be(p,xn) at Ep=5MeV

Howard, et.al., 2001. Nuc. Sci. Eng., 138, 145‐160.0.0E+00

2.0E+07

0 0.5 1 1.5 2 2.5

n th y

Current Status of BNCT. IAEA‐TECDOC‐1223, IAEA. May 2001

Beam Port(10x10 cm2)

Neutron emission points simulated over the entire beryllium surfaces. Be(p,xn) data for 4 MeV protons

Energy (MeV)

B ( ) i ldi d E 5 M V

Howard, et.al., Measurement of the thick‐target 9Be(p,n) Neutron Energy Spectra, Nuc. Sci. Eng., 138, 145‐160, (2001)The only one experimental measurements available so far ……TOF technique, MIT (2000) 

Be(p,xn) neutron yielding and spectra at E = 5 MeV

Be(p,xn) neutron spectra at 0 deg for some energies

Total neutron yield measured at Ep= 4 MeV: Yn 1.05∙1012 s‐1mA‐1

Neutron source gain factor expected at Ep= 5 MeV 2.8 Yn ~2.9∙1012 s‐1mA‐1

Ep=5 MeV Be(p,xn) thick target neutron spectra measurements at the 6 MeV Van de Graff accelerator at LNL new p-recoil detector (Milan Polytechnic)

Be(p,xn) all measured neutron spectra 

1E9

Si-Telescope

1E9 1E9Be(p,xn) neutron spectra comparison with at 0 deg 

eld sr-1)

p TOF (Howard et al., 2001)

1E8

Neu

tron

Yie

MeV

-1

C-1

1E8

Neutron mean energy1 35 MeV

1E8

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.51E7

(

N t (M V)

Current minimum detectable energy due to (n,) discrimination

N t    (M V)

1E70.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5

1.35 MeV

Neutron energy (MeV)

1E70.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5

POLIMI ‐ Silicon TelescopeBe(p,xn)  Ep= 5 MeV  total neutron Yield measured     Yn (4π) = 3.05∙1012 s‐1mA‐1 

N l l d i hTRASCO RFQ B S

Neutron energy (MeV)Neutron energy (MeV) Neutron energy (MeV)

23

Neutron source level expected withTRASCO RFQ + Be target Sn ~1.05∙1014 s‐1

Th B Sh i A bl l tiThe Beam Shaping Assembly solution

71 cm Neutron beam portBe target 

17 a

Proton beam 

BSA identical to the alternative configuration developed withBSA identical to the alternative configuration developed withBe(p,xn) spectra at 4 MeV, but for the D2O moderator regionthickness “a” increased by just 1 cm. Same reflector sizes

MCNPX l l i lNeutron Fluence‐to‐kerma conversion factors from ICRU‐63

G  Fl t k i  f t  f  ICRU 6

MCNPX calculation results

Total measured neutron yield ~3.05∙1012 s‐1∙mA‐1

Gamma Fluence‐to‐kerma conversion factors from ICRU‐46

Agosteo et al., 2010.  Proc. of ICNCT‐14, Argentina (2010)

th (E 0.5 eV)(cm-2s-1)

th total Knth (Gy·h-1)

Kn epi-fast(Gy·h-1)

K(Gy·h-1)

K Kn tot Kn (E>0.5 eV) / th(Gy·cm2)

K / th(Gy·cm2)

IAEA TECDOC-1223 ref. parameters > 1.0E+09 > 0.90 ≤ 2.0E-13 ≤ 2.0E-13

25MCNPX results 4.30E+09 0.96 2.53 0.51 1.42 0.46 0.33E-13 0.92E-13

N & d b ll i

99.9 % Total Dose Rate at the Irradiation port area

95.0 % Total Dose Rate at the Irradiation port area

Neutron & gamma dose beam port wall mapping

Proton beam Proton beam

Epithermal neutrons (0.5 eVE10 keV)Thermal neutrons (E 0.5 eV)

93.6 % Total Dose Rate at the Irradiation port area

90.0 % Total Dose Rate at the Irradiation port area

Proton beam Proton beam

Fast neutrons (E>10 keV) Prompt gammas

C l iConclusionProton source upgrade & LEBT completion is possible in the framework ofTRASCO-3 projectp j

High power coupler test was successful at nominal power. We plan to reach 130%of nominal power (end of this month)of nominal power (end of this month)

RFQ passed all low power tests

Two important points remain:RFQ high power test (September - December 2011)Converter proton irradiation test (next year)

In the mean time…A consortium between INFN, Pavia University and SOGIN was born two monthsA consortium between INFN, Pavia University and SOGIN was born two monthsago to provide the project with necessary funds for completion