A short overview of nuclear facilities and activities at LNS M. Lattuada

A short overview of nuclear facilities and activities at LNS

M. Lattuada

CONTENTS:

Beam production facilities Biggest detection facilities Nuclear research activities

Physics research: Nuclear physics (experimental and theoretical) Nuclear and sub-nuclear astrophysics

Interdisciplinary and technological research: Accelerators and ion sources Informatics Plasma physics Biophysics - Radiobiology Cultural heritage Ion beam therapy

Physics research: Nuclear physics (experimental and theoretical) Nuclear and sub-nuclear astrophysics

Interdisciplinary and technological research: Accelerators and ion sources Informatics Plasma physics Biophysics - Radiobiology Cultural heritage Ion beam therapy

LNS staff: ~ 120 (~ 35 physicists and engineers) Researchers from other institutions: ~ 20 Fellows, Post-doc, … : ~ 40 Graduate/undergraduate students: ~ 40

USERS (participants in at least one experiment at LNS in the last 3 years): 545 (180 from abroad)

CYCLOTRON

TANDEM

EXCYT PRE-INJECTORECR

SOURCES

MEDEA-SOLE-MACISTE

CICLOPE

CHIMERA

MAGNEX

PROTON THERAPY

6O°

8O°

2O° O° 4O°

Layout of the experimental areas

The LNS Tandem accelerator

Stable beams at LNS

The LNS K800 Superconducting Cyclotron can accelerate ions up to 80 MeV/amu

Stable beams at LNS

0

10

20

30

40

50

60

70

80

90

100

0 20 40 60 80 100 120 140 160 180 200 220 240

Mass (a.m.u.)

En

erg

y (M

eV/a

.m.u

.)

0

10

20

30

40

50

60

70

80

90

100

0 20 40 60 80 100 120 140 160 180 200 220 240

Mass (a.m.u.)

En

erg

y (M

eV/a

.m.u

.)

First beam: 8Li (13C beam + graphite target)Last experiment: primary beam 100 W -> average intensity 7· 104 pps)Bottleneck: CEC efficiency ~3 %There is still room for improvement …

Radioactive beams at LNS

Production Target

Final Focus

Fragment Separator


The basic idea is to identify one-by-one each single ion

Charge and mass (Z,A)

Position (x,y)

Energy E

Tagging Technique

Secondary Target

(ΔE,ToF)

(x,y)

(A,Z), E

Secondary Ion

Si-Strip

2424Tagged Ion


20Ne+9Be

SOLE

Superconducting Solenoid

00 60

MEDEA

180 BaF2 detectors

300 1800

MACISTE

8 gas plastic position

sensitive detectors

60

Detection systems at LNS

SiCsI(Tl)

PSD in CsI(Tl)

Z,A for ligth ions

ΔE(Si)-ToF

A - identification for particles stopped in Silicon

HI

pd

t

3He

LiBe

~300 μm

3-12 cm1192

ΔE(Si)-E(CsI)

Z,A for ligth ions (Z<10)

ΔE(Si)-E(CsI)

Z - identification

PSD in Silicon

Z - identification for particles stopped in

Silicon


Main parametersMaximum magnetic rigidity

1.8 T· m

Solid angle 51 msr

Momentum acceptance

± 10 %

Momentum resolution

1/5400

Mass resolution 1/300


Targets: 27Al, 19F, 27Al, 12C, WO3, 28Si

Nuclei investigated: 19O, 27Mg for spectroscopy and 12C,16O,28Al to measure the strength of Fermi (0+), GT (1+) and SD(0-,1-,2-) transitions

52 MeV beam energy 7Be ejectiles detected by MAGNEX spectrometer Angular setting

• Data Analysis under way

December 2007 - July 2008

First MAGNEX experiments: (7Li,7Be) CEX reaction

12lab 187 lab

0lab6lab 133 lab

Tandem experiments at LNS

High resolution spectroscopy of light neutron rich nuclei via multineutron transfer using tandem 18O beam

12,13C(18O,15,16,17O) to study the 13,14,15,16C nuclei

at Einc= 84 MeV

Next: the use of a 14C target will extend the exoticity

of the nuclei that can be studied (16,17C)

Multineutron transfer induced by 18O tandem beams


13C target 50 μg/cm2 thick

Average energy resolution ~ 250 keV (FWHM)

Angular resolution in the CM reference ~1.5 (FWHM)

New collective states between 10 and 15 MeV?

The 13C(18O,16O)15C reaction (2009 experiments)


The trojan horse method for resonant reactions: the The trojan horse method for resonant reactions: the AGB caseAGB case

In the “Trojan Horse Method” (THM) the cross section of an astrophysically relevant reaction A(x,c)c’, can be measured by measuring the three body A(b,cc’)s cross section, where b can be described as x+s:

b

A

x

s

c’c

In the case of a resonant two body reaction the resonance parameters, and in particular the strength, can be extracted through a modified R-Matrix procedure

With a proper choice of the detection configuration, the cross section of the 2-body reaction at sub-Coulomb energy can be deduced from the 3-body one at energy above the barrier.

Upper vertex: direct b breakup into x+s


Lower vertex: virtual A(x,c)c’ reaction

The The 1515N(p,N(p,))1212C reactionC reaction

The 15N(p,)12C, 18O(p,)15N and 17O(p,)14N reactions are crucial to investigate N and O isotopic ratios in AGB stars and constrain their evolution

Recommended value for S(0):735 MeVb

La Cognata et al. PRC 80 (2009) 012801

Low energy direct data show a large spread: extrapolation to energies of astrophysical importance is critical

The THM allows to extend the measurement to zero energy: • no extrapolation• no electron screening


The The 1818O(p,O(p,))1515N reactionN reaction

First time observation of the 20 keV resonance in the 18O+p interaction Absolute values of the strengths obtained by normalizing to the known resonance at 144 keV

(eV) present work

(eV) NACRE

20 keV 8.3 +3.8-2.6 10-19 6 +17

-5 10-19

90 keV 1.8 ± 0.3 10-7 1.6 ± 0.5 10-7

In case of a narrow resonance the reaction rate is determined by the resonance strengths

La Cognata et al. PRL 101 (2008) 152501La Cognata et al. ApJ 708 (2010) 796


Structure effects in collisions induced by halo nuclei

Elastic scattering 9,10,11Be+64Zn @Ecm=24.5MeVExperiments performed at LNS and ISOLDE

Similar elastic scattering angular distribution measured for 9,10Be+64Zn .

11Be+64Zn scattering exhibits a strong suppression of the elastic cross section at small angles absorption occurring at large distances due to 11Be halo structure.

No effect observed for the weakly bound 9Be

Reaction cross sectionReaction cross section99Be)=1.1b, Be)=1.1b, 1010Be) ≈1.2bBe) ≈1.2b

1111Be) ≈2.7bBe) ≈2.7b

1111Be+Be+6464ZnZn1010Be+Be+6464ZnZn 99Be+Be+6464ZnZn

1111Be+Be+6464ZnZn1010Be+Be+6464ZnZn 99Be+Be+6464ZnZn

11Be+64Zn break-up/transfer angular distribution

≈≈1.1b1.1b

The large break-up cross section partially due to break-up/transfer events (rec/bu-tr ≈0.4)


Be

B C

Li

123

31

Time-scale measurement of IMF products

<N

/Z>

Dynamical fission in 112,124Sn+58,64Ni at 35 MeV/A and 197Au+197Au at 15 MeV/A

neutron enrichment of IMF emitted from

the neck

CHIMERACHIMERA results results

CS experiments at LNS

PRL 101 (2008)262701

PRC 71(2005)044602

8He

Study of nuclei at the drip line with FRIBs fragmentation beams

15B

11Li

The 4 detector allows kinematical coincidence to extract angular

distributions for elastic and inelastic processes using radioactive beams

40Ca + 12C 3 coincidences

CHIMERA: very recent resultsCHIMERA: very recent results

CS experiments at LNS

12B+d elastic scattering

Bose condensate3 correlations to measure

the size of the emitter

The first EXCYT experiments were designed for low intensity The first EXCYT experiments were designed for low intensity beam beam

•BIGBANGBIGBANG: 4He(8Li,n) integrated cross section (~ 102 mb)

•RCSRCS: measurement of 8Li + 28Si total reaction cross section using an active 28Si target

•RSMRSM: 8Li + 4He scattering excitation function in a single run, with the resonant scattering method on thick gas

target

EXCYT experiments at LNS

Start ToF


Useful in experiments with low intensity beams: excitation function measured in a single run. Scattering cross section measured at 180o c. m. angle

BUT … … angular and energy resolution change with energy … accurate knowledge of stopping power is needed

Resonant elastic scattering on thick helium target to look for 8Li-configurations of 12B

8Li* 8Li

E E

t1

t2

Stop ToF

4He gas

Calculated ToF vs E

ToF discriminates elastic events from inelastic scattering events

Inelastic

coun

ts

Elastic

ToF

coun

ts

EXCYT experiments at LNSE(MeV)

1 nsec resolution

Eexc~ 1 MeV

Preliminary

The 6.15 MeV state populated by Coulomb

excitation (E1 transition) on Pb target

Full detection and identification of decay products

Two-proton decay: the 18Ne case

FRIBs experiments at LNS

Energy, angle and relative momentum correlations

18Ne beam produced at 35 MeV/u

by 20Ne projectile fragmentation

Two-proton radioactivity

predicted in the 60’s (Goldansky)

Two particle correlations in nuclei

Role of the pairing

(669)% direct three-body

(32)% virtual sequential

(317)% 2He decay

G. Raciti, et al., Phys. Rev. Lett. 100, 192503(2008)

Hunting for pp decay

FRIBs experiments at LNS

208Pb18Ne

18Ne*16O

2He

208Pb18Ne

18Ne*16O

Work in progressWork in progress

New EXCYT beams (15O ?)

FRIBs: front-end and tagging detector : high rate capability improvement of CS extraction line transport and acceptance

New chamber for SERSE (under construction) improved intensity

(good for EXCYT and FRIBs)

Coupling of EDEN with MAGNEX ?

High energy astrophysics

far cosmic “accelerator” (particle energy>1017eV)

neutrinos

electromagnetic radiation (radio, light, UV, X, gamma)

protons

interstellar radiation and matter

“Submarine Telescope” for very high energy neutrinos.

It will allow to explore regions and phenomena in the Universe never observed so far

neutrinomuon

Cherenkov light

Optical module

s

Neutrino observatory project at LNS

European framework

• Consortium of the Institutes that develops and supports the pilot projects in the Mediterranean Sea. Consists of Institutes from 10 European Countries (Cyprus, France, Germany, Greece, Ireland, Italy, The Netherlands, Romania, Spain, U.K.)

• Large European Research Infrastructure– Included in the first roadmap for the European RI of the ESFRI

• Design Study project– Approved under the 6th FP– Conclusion in October 2009 with publication of the Technical Design

Report

• Preparatory Phase project– Approved under the 7th FP, started on March 1st 2008– Coordinated by INFN-LNS

KM3NeT


Phase1 project:a test site in Catania

Double-shielded cable (2.330 m)

Single shielded cable (20.595 m)

North branch5.220 m

South branch5.000 m

BU

SN-1Shore stationShore station

An underwater infrastructure has been realized by the Laboratori Nazionali del Sud to test detector prototypesA seismic and environmental observatory of INGV has been installed and connected to the EO cable

• Project jointly funded by INFN and MIUR:• Realization of shore and deep sea infrastructures • Design and realization of a subsystem of the km3 including key elements of the detector• Deployment and connection of a junction box and a fully instrumented detector module

consisting in a four storey tower• Study of the water properties and of the seabed morphology


Phase2 project:a deep sea station at Capo Passero

OBJECTIVES- Realization of an underwater infrastructure at a depth of

3500 m in the Capo Passero site- Test of the detector installation procedures at 3500 m- Installation of a 16 storey tower- Long term monitoring of the site

PROPOSED INFRASTRUCTURE- Shore station in Portopalo di Capo Passero to host the

power feeding and the data acquisition systems- 100 km electro-optical cable connecting the underwater

infrastructures with the shore station

STATUS- The electro-optical cable (about 40 kW) has been deployed- A building located inside the harbor area of Portopalo has

been renovated to host the shore station.- A 16 storey tower has been deployed last month to test the

structure and the installation operations from the point of view of mechanics


Through Tandem @7MV

47%

7.0 • 104

70%

5.0 • 104

On target

8Li3+

Primary beam power

100watt 5.4•106

CEC (10 keV)

8Li-

2.8%

Through platforms

8Li-

Through 2nd stage

Tandem entrance

1.5•105

100%

1.5 • 105

100%

1.5 • 105

100%

1.5 • 105

LEBI1

8Li+

Production with the sliced target is at least 3 times the value found with the former cylinder target

Tandem transmission can still be increased by improving beam optics and moreover it will be higher at larger terminal voltages

With a primary beam of 200 Watt an intensity close to 2·105 pps can be obtained

bottleneck


Proton rich with 58Ni+27Al and 20Ne+9Be

Neutron rich with 40Ar+9Be

Light proton rich with 12C+9Be

Production Results


18Ne,17F Production

(May-June 2009)

300÷400 enA of primary 20Ne beam

60 kHz of secondary beam on the tagging detector

5 kHz of 18Ne and 3 kHz of 17F

89 THREE-FOLD TELESCOPE ARRAY

81 TWO-FOLD TELESCOPE ARRAY


Search for cluster structures in n-rich B isotopes

Theoretical calculations (AMD) predict the existence of Li-He structures in B isotopes.

Kanada-En’yo & Horiuchi, PR C52(1995)647

Theoretical calculations (AMD) predict the existence of Li-He structures in B isotopes.

Kanada-En’yo & Horiuchi, PR C52(1995)647


Aim of the experiment was to search for possible + 8Li configurations of 12B, by looking at resonances in the elastic scattering of the two components in inverse kinematics

Ebeam~30 MeV 10 MeV< Eexc<20 MeV

Aim of the experiment was to search for possible + 8Li configurations of 12B, by looking at resonances in the elastic scattering of the two components in inverse kinematics

Ebeam~30 MeV 10 MeV< Eexc<20 MeV

Documents

A short overview of nuclear facilities and activities at LNS M. Lattuada