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Stable beams
E*
ISOL Radioactive beams
J
Fragmentation beams
E*
Time
Out of the box?
I) Are nuclei at the limits of particle stability, beyond what
can be measured today going to answer THE questions* ?
How much beyond do we need to go and why ?
Are there “ key “ nuclei?
Précision
How much are we hampered by lack of P and A in the measurements ?
Will looking at high precision data and detailed information help?
Do we need to measure all observables measured using stable beams
with Nuclei far from stability ?
Do we have enough data today to look at in a consistent manner
already to address THE questions* ?
Did we fully exploit the data that we already have ?
Accuracy
II) Are there new experimental methods that we need to invent ?
What do you dream of measuring but cannot today?
Is 10 days the maximum we can invest in an experiment today?
*THE questions
How compelling is our need a next generation ISOL facility ?
III) Do we need to understand (dynamics) - the beauty of the reaction mechanism
Should we differentiate between authors/acknowledgment or go the Particle Physics way
You die the day your dream dies
Summary: Status and perspectives
* Multipole response of nuclei
- Not much information for unstable nuclei so far
- PDR problem, no GDR systematics, no GQR, no GMR
- In principle, experimental techniques have been developed, need beams and investment !
- -> RIBF, FAIR FRIB
* EoS of asymmetric matter
- Many attempts and constraints already; relation of observables to symmetry energy: model
dependencies -> many methods? better theory? Changes along isotopic chains ?)
- Heavy ion collisions with n-rich beams might provide info for higher densities
how large is model dependence ?
* Single-particle structure and correlations
- How can we understand the quenching of s.p.-strength as a function of Sn-Sp ?
- Can give QFS cross sections reliable information ?
- Observables directly related to tensor/short-range correlations ?
- E.g. experiments like p,2pn with radioactive beams
* Drip line
- Elaborated experimental techniques available
- Haloes and states beyond drip line can be studied with high precision up to Z=8 now
- Heavier haloes at RIKEN, later FIR and FRIB (starting 2020)
* Stable nuclei
- Many open questions even for stable nuclei, precision experiments needed,
- also important to pursue with RIB experiments and interpretation
* Reaction Theory ! Ab initio theory <-> cross sections
Conclusions-Nasser
 Many-body theories have come a long way. These days, they can work with
chiral nuclear forces as well. 3NF should be better understood though. New
reaction theories based on these new developments should now be worked on.
 Light hadron scattering can be used at low momentum transfers to probe
fundamental properties of nuclei such as density distributions, compressibility
and in general collective properties, beta-decay rates etc. Equation of state of
asymmetric matter is highly desired.
 Electron scattering from radioactive nuclei sheds light on charge-density
distribution at low momentum transfers. BE(2) can be studied in several cases.
Magnetic properties and QFS will prove to be very difficult with the present
intensities.
 NOTE: This is only a subset of all nuclear-structure activities around the world.
Other questions
 Evolution of nuclear properties as fn of J,T
Large acceptance spectrometer +next gen Gamma-arrays
Spectroscopy of fission fragments
 Fission new variables (on the dynamics of fission)
 Tunnelling at the femtometer scale
 Pairing transfer reactions +
Np pairing
Experimental signatures for change of pairing as a function of isospin.
 Will the Search for new shell closures help inverse the problem to
better define the interaction ?
Summary of talks
•
Symmetry energy and skins (isovector) (e.g PDR …) difficulties to be overcome,
complementary to HIC

Drip line and beyond neutron unbound states …. Neutron radioactivity ?
Nucleon –nucleon correlations Clustering e.g tetra n …, gaint halos’s (?)
Single particle strengths
quenching of spectroscopic factors …

•
Electron scattering --> charge density distributions, BE(2) values if the
intensities allow and then to more difficult channels (like magnetic properties
or spectral functions) but then you really need high intensities.

• Low-q: matter density distributions, Giant resonances, Gamow-Teller
resonances

• Need for 3NF ?

Key questions in SHN research
Key Questions in SHN research (Micheal Bloch)
• Where does the nuclear chart end?
• Is the concept of magicity still useful in SHN?
• How strong and localized are shells, e.g. N = 162, 184?
• Experimental confirmation of Z/A-assignment of SHN (Z=114-118)
• How to best produce more neutron-rich SHN?
• Are SHN formed in stellar nucleosynthesis?
Experimental challenges in SHN research
• Cw accelerator for high-intensity stable beams (>1014/s)
• (thin) targets that can stand high-intensity (cw) beams
• sufficient material for additional actinide targets (254Es,
251Cf,
…)
• Compact recoil separator to access short-lived SHN
• high-intensity radioactive beams (>1010/s) with good beam quality
• macroscopic amounts of transactinde elements
What happens when an exotic nuclei undergoes fast rotation
The next Frontier of Nuclear Physics ?
+
AIP Conf. Proc. 1498, 84 (2012)
p
n
p
n
EoS of asymmetric nuclear matter… time matters…
Projectile
Resonance decays
Clusters
Target
Large (N-Z)2
(RIBS and Stable!)
Pre-equilibrium
Fragmentation
Asy-EoS: E(ρn, ρp,T)
WHY?
Nucleon-nucleon interaction (2&3-Body forces, etc.)  study also dynamics!
Neutron Stars, Supernovae II (neutrinosphere, nucleosynthesis)
• Measure observables with high resolution + compare to models
 Space-time probes: Imaging at “femtoscopic scale”? “when” and
“where” particles are produced?
 Clusterization + resonances at low ρ  Dynamics & Spectroscopy
- Clusters (multi-alpha,…) and unbound states affect EoS (Khan)
- Spectroscopy? “in-medium” vs “free”? (ex. BE)
Will the concept of single particle state picture fail
at some stage ?
Go towards heavy Nuclei
Heavy nuclei below U
 Transfer reactions with high statistics
‘get the whole strength in a consistent
way (Structure and reaction in the same
frame work)?’
(extrapolated towards the drip line)
 Heavy nuclei below U
 Will there be a diminishing role of 2
body interaction and just be
manifestions of manybody effects
 Role of 3 (4) body forces in destroying
gaps ?
 Will Shell structure evolve to
clusterization and fnally
band structure of nuclei!!!!
10 to 30 MeV/u
Exploring Quantum mechanics at the femtometer scale
Decoherence, Tunneling of composite objects
Is there anything new to learn ?
Specaility of a nuclear system
Strong interplay of many open and virtual channels
Coherent superposition
Nuclear collisions – isolated, no external environment
– internal environment from many
complex excitations while merging
large
small
matter overlap
Sub-system
system
Compound nucleus
Largerenvironment
system
Complex
Fusion crosssection (mb)
Dasgupta et al ANU
System “entangled”
Sub-system
“entangled”with
withenvironment
rest of
Loss of coherence in smaller system
system
This could be one way of looking at this
Quantum
Decoherence ?
M. Schlosshauer, Decoherence and the quantum to classical
transition, Springer (2007)
Questions about Pairing in weakly bound systems
Correlation
Length
Matsuo PRC 73 (2006)044309
N. Pillet et al. PRC 76 (2007)024310
Separation
Skin
Di-neutrons
Effects on Two-neutron transfer reactions
(t,p) and (p,t) reactions in reverse kinematics.
Do we expect an enhancement of the cross-section ?
Sn » l
Role of isoscalar (T=0) and isovector (T=1) pairing
Does isoscalar pairing give rise to collective modes?
Direct reactions are unique tools in our experimental study of exotic nuclei
Two particle transfer reactions provide specific tools to probe
the amplitude of pairing collective modes
Heavy Ion Transfer. Josephson effect?
The 60Ni+116Sn system - Transfer reactions studied at
far sub-barrier energies with the PRISMA Spectrometer
the Total Kinetic Energy Loss
distributions show a concentration of
strength close to the ground to
ground state transitions
in a phenomenological approach,
one gets an enhancement factor
significantly larger than usual for
pure neutron transfer
D.Montanari et al., INPC2013 and Fusion2014
Technology +stable beams
Prompt spectroscopy of fission fragments will help us to probe excited states at BOTH relative
high spin and isospin in heavier nuclei
Excited states of of 400 Nuclei M,Z at one go
AGATA_0.71p+VAMOS+++
To look for new Phenomena High spin
Isospin
weak binding (neutron rich not dripline)
High Spin and High Isospin