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Nuclear Physics INTRODUCTION from nuclei to stars introduction 1
Nuclear Physics INTRODUCTION
from nuclei to stars
introduction 1
SU(3)×SU(2)×U(1)
The untold legend of the human quest for ultimate components of matter
The outermost Aristotle’s sphere "The final cause, then, produces motion by being loved, but all other things move by being moved" Aristotle Metaphysics 1072b4
the hidden paradigm in material science : smaller ≈ more “fundamental”
introduction 3
Higgs process explains mass of quarks ≈ 5 MeV
quarks & gluons medium explains nucleon mass ≈ 1000 MeV
nucleons in medium binding energy ≈ 1000 MeV
the origin of the mass of (≈90% of) visible universe: due to in-medium (interacting) elementary particles mass is the first expression of the emergence of complexity
The atomic nucleus is the first microscopic step towards complexity and diversity in the universe
introduction 4
Sir Fred Hoyle in 1967 at California
Institute of Technology
Example : the nuclear doorway to the emergence of life
The 3 process, a critical step of the creation of the life’s elementary constituents : C, O etc
introduction 5
ρ T1/2 > 1 an
nouvelles formes de radioactivité
12C
Why not focus only on 12C to study nuclear physics ?
introduction 6
Neutron stars merging event detected by LIGO-Virgo followed quickly by EM emission at all frequencies August 17th 2017
©ESO
/L. Calçad
a/M. K
orn
messer
on earth fission of actinides
kilonova
introduction 7
Why the nuclear problem is far from being solved ?
raw nucleon-nucleon interaction
in medium
in medium (many mody aspects)
an effective interaction… emerging properties
pairing
tenseur
3-corps
STRUCTURES
spin-orbite
j< j>
the heart of the nuclear problem: 1) how to solve (many body problem) ? 2) what nuclear interaction (in medium) use ?
make in medium conditions vary ≡ explore unstable nuclei
introduction 8
Darwin: a naturalist's trip, a theory of evolution at the end of the journey Nuclear physics: reaching the theory is the initial goal of the trip
Our sea : the nuclide chart Our boat : models Our sails : accelerators and instruments Our wind : experiments
introduction 9
Why the nuclear problem is far from being solved ? (the question of theory in nuclear physics)
the heart of the nuclear problem: 1) how to solve (many body problem) ? 2) what nuclear interaction (in medium) use ?
a fruitful idea : individual particles moving inside the nuclear field but they are not nucleons !
ℋ𝐶𝑀 + ℎ𝑟𝑒𝑠
dynamics of « individual » particles
what perturbs this dynamics
some latitude for this choice
Vittorio Somà (theoretical aspects) and me (phenomenological aspect) will lead you to this key concept at approx. same speed from two complementary points of view introduction 10
Phenomenological approaches to nucleus: shapes, shells and “exoticity”
David Verney
I- Saturation of nuclear forces
1- Nuclear sizes and mass : empirical aspects -electron scattering, laser spectroscopy -mass measurements
associated current research fields and illustrations
evidence for saturated substructures -equation of state of nuclear matter, -clustering, Ikeda diagrams, Hoyle state 2- Exchange forces and saturation
symmetry energy charge energy stability of nuclei
3- Generalization to the liquid drop model
introduction to nuclear deformation limit of existence of nuclei : fission barrier, drip lines -Towards super heavy nuclei
II- Internal structure of the nuclei
1- Magic numbers, shell effects and the concept of single particle
beyond the liquid drop
2- Beyond the single particle picture –residual interactions
III- Correlations
1- Pairing
empirical aspects pairing phenomenology
2- Quadrupole coherence
microscopic origin of the nuclear deformation
empirical aspects
simple cases
-shell evolution in exotic nuclei
-how far is a residual interaction from a bare nucleon-nucleon interaction ?
introduction 11
IV- Collectivity associated to the nuclear surface motion*
1- Vibrations - spectroscopy – the -tracking revolution : AGATA -exotic shapes
associated current research fields and illustrations
2- Rotations
the rotor
3- coupling to single particle degrees of Freedom
Coriolis effect
Phenomenological approaches to nucleus: shapes, shells and “exoticity”
introduction 12
*if time allows
introduction 13
*if time allows
Theoretical aspects – Vittorio SOMA
introduction 14
Astrophysical aspects – Fairouz HAMMACHE
Nuclear Astrophysics lecture
How do stars form and evolve & what powers them?
• Principles of stellar structure & evolution
• The observed properties of stars
• Chemical abundances from stellar spectra
& meteorites
Star birth clouds the Eagle nebula
(M16) Hubble 1995
solar spectrum (R. Kurucz,
KittPeak National
Observatory)
Ensisheim meteorite,
The Hertzprung Russel (H-R) diagram
Lecture I
Hubble Telescope
Sola
r A
bu
nd
an
ce
What is the origin of the chemical elements present
in our Universe & which nucleosynthesis processes
are responsible of the observed solar abundances?
• Big-Bang nucleosynthesis
• Cosmic ray nucleosynthesis
• Stellar nucleosynthesis:
Calm hydrostatic & explosive burning
• Nucleosynthesis beyond iron
Supernova SN1987A Our sun Neutron star mergers
Lecture II
Observations
Astrophysics
Modelling
Thermonuclear reaction rates
Nuclear physics (Cross-sections, resonance parameters, -decays, masses )
Lecture III
Abundances
Abundances
0
/
2/3
2/1
aX)(
18=v dEEeE
kT
kTE
From nuclear physics to abundances
The tunnel effect
XY
aXXX
ndt
dn
vYnndt
dn
AN
Lecture IV Experimental approaches in nuclear astrophysics
• Direct measurements of cross-sections of charged-particle induced reactions :
Characteristics, experimental procedures, requirements & challenges Laboratory Underground for
Nuclear Astrophysics, LUNA
facility
E (keV)
Cou
nts
/day
BGO
• Direct measurements of cross-sections of neutron induced reactions in s-process:
Activation and Time of Flight methods
• Indirect measurements: Transfer reaction method resonance parameters (Ex, decay width,...)
STELLA project
b x
A A
X
C* MUGAST AGATA
VAMOS
Spiral1
radioactive
beams
DW
X
x
C
xd
dSS
d
d
exp
d
/d
(m
b/s
r)
Split-Pole
LOG
SCALE
direct measurements
(E)
non-resonant
resonance
extrapolation
Ste
llar
ener
gy
E c.m
