# Physics opportunities with the SPIRAL upgrade

Europe/Paris
Description
This workshop aims at discussing the physics opportunities that will soon become available at SPIRAL 1 thanks to the progresses of the current upgrade.
Participants
• Abdou Chbihi
• Alain Gillibert
• Alex Laffoley
• Amel KORICHI
• Bertram Blank
• Beyhan BASTIN
• Caterina Michelagnoli
• Christian Aa. Diget
• Costel Petrache
• Damian Ralet
• Daniel Napoli
• Daniele Mengoni
• Emmanuel Clement
• Etienne Liénard
• Franck Delaunay
• Freddy FLAVIGNY
• Geoffrey-Fathom Grinyer
• Gilles de FRANCE
• Gilles Quéméner
• Iulian stefan
• Joa Ljungvall
• Joao Pedro Ramos Ramos
• Lynda Achouri
• Magda Zielinska
• Manuel Caamaño
• Marek Lewitowicz
• Marlène Assié
• Mickaël Dubois
• Nigel Orr
• Nizamettin Erduran
• Olivier BAJEAT
• Pascal Jardin Jardin
• Pauline Ascher
• Pierre DELAHAYE
• Silvia Lenzi
• Silvia Leoni
Support
• Monday, 8 February
• 13:30 14:00
Registration

Registration

• 14:00 15:40
• 14:00
Speaker: Dr Marek Lewitowicz (GANIL)
• 14:10
Introduction 5m
Speaker: Dr Pierre DELAHAYE (GANIL)
• 14:15
Speakers: Dr Laurent Maunoury (CNRS GANIL) , Mr Mickael Dubois
• 14:50
Day 1 beams 25m
Speaker: Dr Pierre DELAHAYE (GANIL)
• 15:15
Performances of the SPIRAL1 charge breeder 25m
In the framework of the SPIRAL1 upgrade under progress at the GANIL lab, the charge breeder based on a LPSC Phoenix ECRIS, first tested at ISOLDE [1] has been modified as to benefit of the last enhancements of this device from the 1+ / n+ community [2]. Prior to its installation in the midst of the low energy beam line of the SPIRAL1 facility, it has been tested at the 1+/n+ LPSC test bench to evaluate its performances and investigate the future operational modes. This contribution shall sum up the results obtained at LPSC concerning the 1+ to n+ conversion efficiencies for noble gazes as well as for alkali elements and the corresponding transformation times. [1] P. Delahaye et al, Review of Scientific Instruments. 77, 03B105 (2006) [2] R. Vondrasek et al, Review of Scientific Instruments 83 113303 (2012)
Speaker: Dr Laurent Maunoury (CNRS GANIL)
• 15:40 16:10
Coffee break 30m
• 16:10 18:10
Future opportunities
• 16:10
Ongoing R&D on target - ion source systems 35m
Speaker: Dr Pascal Jardin
• 16:45
New targets 25m
Speaker: Mr Olivier Bajeat
• 17:10
ISOL R&D at ISOLDE 35m
Speaker: Dr João Pedro Ramos
• 17:45
Discussion 20m
• Tuesday, 9 February
• 09:00 10:30
DESIR Physics
• 09:00
Fusion-evaporation reaction at SPIRAL1 30m
Heavy ion beams from CSS1 allow to produce proton-rich ions via fusion-evaporation reactions. Different heat resistant targets would be bombarded with beams of about 6 MeV/A. This would allow to send these proton-rich nuclei to DESIR and to CIME for acceleration. In the talk, calculated production rate will be presented.
Speaker: Mr Bertram Blank (CEN Bordeaux-Gradignan)
• 09:30
Precision measurements in mirror beta decays 30m
In this contribution, we propose to measure the beta-neutrino angular correlation parameters in mirror beta decays using an upgraded LPCTrap setup at LIRAT. The main interest lies in the determination of Vud which can be deduced from this set of transitions if the GT/F mixing ratios are precisely known. This is precisely the purpose of the proposed measurements. The setup also provides the charge state distributions of the recoiling ions, enabling to study the atomic processes involved in these ions when the electron cloud is disturbed. The most interesting nuclei will be highlighted, among the new beams produced at SPIRAL1.
Speaker: Prof. Etienne Liénard (LPC Caen)
• 10:00
Studies of Superallowed Fermi Beta Emitters Using the IBE Decay Station 30m
The study of superallowed Fermi β transitions between nuclear isobaric analog states of spin Jπ​ = 0+​ provides demanding, and fundamental, tests of the properties of the electroweak interaction. In particular, high-precision measurements of the β-decay ft values for superallowed Fermi β emitters with isospin T = 1 have been used to validate the conserved vector current (CVC) hypothesis to better than 12 parts in 10^5​ and provide the most precise determination of Vud, by far the most precisely determined element of the Cabibbo-Kobayashi-Maskawa (CKM) quark mixing matrix. Much current interest lies in the set of superallowed decays with Tz =−1 parents, as the isospin symmetry breaking corrections are, in general, larger than those for the Tz = 0 parents of the same mass due to an increased radial-overlap mismatch between the proton and neutron wave functions in the parent and daughter nuclei. However, high-precision measurements of the ft values for these decays are, in general, more challenging than for the Tz = 0 parents, due both to the fact that they are further from stability, and their daughter nuclei are in general also β unstable and give rise to unwanted but unavoidable time-dependent β-decay backgrounds. Recent experimental efforts, in combination with extensive simulation work, have, however, demonstrated that these challenges can be overcome. At the IBE low-energy decay station, a program to investigation Tz=−1 superallowed Fermi β emitters has been previously established. The setup uses a moving tape collection system and couples a plastic scintillator with a precisely calibrated HPGe to perform both half-life and branching ratio experiments simultaneously. Possible experiments for those superallowed emitters that are, or are expected to be, available at SPIRAL1 with sufficient intensity and purity will be discussed. This talk will highlight the complementarity of this program with similar studies performed at LISE, ISOLDE, and TRIUMF as well as the decays of T=1/2 mirror nuclei at LPCTrap.
Speaker: Dr Alex Laffoley (GANIL)
• 10:30 11:00
Coffee break 30m
• 11:00 12:20
DESIR Physics
• 11:00
Mass measurements of light neutron-rich nuclei with SPIRAL1 beams 25m
Mass spectrometry of short-lived neutron-rich nuclei give access to observables like 2n separation energies, which are sensitive to nuclear structure (shell effects, deformations, …) and therefore allows to probe the nuclear force far from stability. The SPIRAL1 upgrade offers the possibility to access masses of exotic nuclei which are currently either unknown or measured with large uncertainties. Different physics cases will be presented. Penning traps and MR-TOFs are nowadays the instruments of choice to measure atomic masses with high precision. Performances of these two different systems will be described. The possibility of installing PILGRIM at LIRAT for the commissioning would allow to measure masses in the near future. On a longer term, such measurements are foreseen at DESIR with MLLTRAP or an MR-TOF with more possibilities thanks to the high-quality and high-purity beams delivered to DESIR.
Speaker: Mrs Pauline Ascher (CENBG)
• 11:25
Beta-delayed two-proton emission 25m
Beta-delayed 2p emission is an exotic decay mode close to the limits of stability.Like in other cases of 2p emission, the decay may go through intermediate levels, if energetically available, or be a direct 2p process by the simultaneous emission of two protons. In this last case, the two protons may reveal angular and energy correlations which could be compared to nuclear structure and dynamics models to study effects like pairing, barrier penetration etc. Possible experiments with SPIRAL1 beams will be presented.
Speaker: Mr Bertram Blank (CEN Bordeaux-Grradignan)
• 11:50
Discussion - feasibility of beams 30m
• 14:00 16:00
ACTAR TPC, nuclear structure and reactions with accelerated beams
• 14:00
ACTAR TPC: First experiments with SPIRAL1 beams 30m
The active target and time projection chamber (ACTAR TPC) is a novel high-luminosity gas-filled detection system that features a highly pixelated pad plane of more than 16K fully digitized electronic channels for studies of reactions and decays of nuclei furthest from stability. Design of the first (cubic) chamber is essentially complete and construction is ready to begin. Commissioning and the first experimental campaign with ACTAR TPC and SPIRAL1 beams are foreseen in 2017 in the G3 experimental hall. These experiments represent the first scientific deliverables of the ERC project. In this presentation, the timeline of the project and experiments being considered for the first ACTAR TPC campaign with SPIRAL1 beams will be discussed along with our requirements in terms of beam intensity, energy, and purity.
Speaker: Dr Geoffrey-Fathom Grinyer (GANIL)
• 14:30
Role of nuclear structure in fission around neutron-deficient Pt 20m
The expected production of heavy ions after the Spiral1 upgrade opens a small window for the study of new fission modes recently found in 180Hg [PRL 105, 252502 (2010)]. These reveal a new role for structure effects, not observed in fission of actinides. The competition between the Coulomb barrier and the foreseen energies of the new beams would allow the study of fusion-fission around neutron-deficient Pt, just two protons away from Hg. From an experimental point of view, observables such as the neutron-proton partition of the fission fragments are a useful tool to tag the presence and influence of structure effects. These observables can be obtained with the use of the spectrometer VAMOS, providing a complete characterisation of the fission fragments and the scission point.
Speaker: Dr Manuel Caamaño (Universidade de Santiago de Compostela)
• 14:50
Near and sub-barrier fusion of neutron-rich light nuclei 20m
Speaker: Dr Abdou Chbihi (GANIL)
• 15:10
Spectroscopy of light nuclei at the drip lines 30m
Speaker: Dr Manuel Caamaño (Universidade de Santiago de Compostela)
• 15:40
Feasibility of SPIRAL beams 20m
• 16:00 16:30
Coffee Break 30m
• 16:30 18:30
AGATA with SPIRAL beams
• 16:30
Detailed spectroscopy 112Cd and 240Pu isotopes using fusionevaporation reactions with 6He beam from SPIRAL1 20m
Speaker: Amel KORICHI (CSNSM-IN2P3/CNRS)
• 16:50
Direct isospin mixing measurement in Coulomb excitation of an 38mK isomeric beam 20m
Speaker: Dr Gilles de FRANCE (GANIL/IN2P3/CNRS)
• 17:10
Population of the N=Z region around the 100Sn via cluster emission. 20m
Speaker: Dr Eric Bonnet (CNRS-In2p3)
• 17:30
Probing the H–buring rate through the CNO–cycle via the Coulomb–excitation of 15O 20m
Speaker: Mrs Caterina Michelagnoli (GANIL)
• 17:50
Study of explosive hydrogen burning in classical novae using 30P and 25Al radioactive ion beams 20m
Classical novae outbursts are very special events since they are the 3rd most energetically ones after gamma-ray bursts and supernovae. The nucleosynthesis network involved in such events is now mainly known experimentally with a few exceptions such as the $^{25}$Al(p,$\gamma$)$^{26}$Si and $^{30}$P(p,$\gamma$)$^{31}$S reactions. In this contribution we would like to emphasize the importance to develop $^{25}$Al and $^{30}$P radioactive ion beams with intensities of the order of 10$^{5}$ pps.
Speaker: Nicolas de Séréville (IPN Orsay)
• 19:30 21:30
Workshop dinner

Dinner down town at 'La Manufacture'

• Wednesday, 10 February
• 09:00 11:00
AGATA with SPIRAL beams: Shared session with the AGATA workshop
• 09:00
Study of light nuclei with A=25 via multi-nucleon transfer reactions induced by radioactive beams 20m
Speaker: Dr giovanna benzoni (INFN)
• 09:20
Lifetime measurements in the A~70 region using the relativistic Coulomb excitation and three-foil plunger techniques 20m
Speaker: Dr D. M. Cullen
• 09:40
Mirror symmetry in the sd shell close to the proton drip line 20m
Speaker: Andreas Vogt (Institute for Nuclear Physics, University of Cologne)
• 10:00
29Mg: Tracking shell evolution toward the island of inversion 20m
Speaker: Dr Adrien Matta (University Of Surrey)
• 10:20
Study of n-p pairing in fp-shell through two-nucleon transfer reactions 20m
Speaker: Dr Marlène Assié (IPNO)
• 11:30 13:00
AGATA with SPIRAL beams: Shared session with the AGATA workshop
• 11:30
Mapping of neutron orbitals around N=28 using 56Ni(d,p)57Ni 20m
Speaker: Freddy FLAVIGNY (IPN Orsay)
• 11:50
Oblate driving force in n-deficient nuclei above 56Ni: occupation in 68Se 20m
Speaker: Mr Daniele Mengoni (University and INFN - Padova)
• 12:10
Structure of low-lying states in 43,45Ar studied using Coulomb excitation of SPIRAL beams 20m
Speaker: Magda Zielinska (CEA Saclay)
• 12:30
Shape transition along and across N=28: 0+ 2 in 46,48Ar 20m
Speaker: Mr Daniele Mengoni (University and INFN - Padova)
• 12:50
Concluding remarks SPIRAL1 beams 10m