Electromagnetic Force
description
Transcript of Electromagnetic Force
Electromagnetic ForceQED
Strong Force
QCD
Gravitational ForceGeneral Relativity
galaxy1021 m
matter10-1 m
crystal10-9 m
atom10-10 m
atomic nucleus10-14 m
electron
nucleon10-15 m
<10-18 m
quark
DNA10-8 m
quark-gluon plasma
The Physics of Nuclei Physics of Nuclei involves many diverse phenomena at vastly different scales, from elementary entities to stellar objects
Atomic nucleus: Atomic nucleus:
Z protons, N neutrons
Complex many-body system where three interactions (strong, weak and Coulomb forces) come into play
Very dense matter: 99.9% of atomic mass
(a tablespoon of nuclear matter would weigh as much as 3000 aircraft carriers)
THE ATOMIC NUCLEUS: core of matter, fuel of stars
Weak ForceStandard Model
The hierarchy of
decreasing dimensions:
from galaxies to quarks,
through the Earth,
molecules, atoms and
nuclei
THE ORIGIN OF NUCLEI: we are all made of stardust
tim
e15 billion years
1 billion years
300.000 years
3 minutes
1 thousandth of a second
After the Big Bang: quarks & gluons then hadrons then H & He [Li,Be]
Heavier elements:created in nuclear reactions in stars and in stellar explosions, going on ...
On Earth today:only stable nuclei very small fraction of all possible (Z,N) !!
We have a successful description of the nuclei
we know but … our understanding of the effective interaction in nuclei is limitedlimited and possibly flawede.g. little knownlittle known about the dependence with
asymmetry (N−Z)∕(N+Z)
THE ADVENT OF RADIOACTIVE ION BEAMS (RIB): ‘gene pool’ of nuclei on Earth brings a new era
production ofproduction of exotic nucleiexotic nuclei with very different N, Z numbers from with very different N, Z numbers from
the known isotopesthe known isotopes achieved with RIB facilitiesachieved with RIB facilities
experiments start unveiling the properties of short lived, weakly bound nuclei far from stability
extend our knowledge of nuclear structure
Major next generation facilities planned or underway in Europe (GSI, EURISOL), the USA (RIA), Japan (RIKEN), ...
Progress in accelerator
and detector technology
makes a bold leap forward
possible:
New phenomena observed physics of weakly bound quantum systems
Theorists served with an unprecedented wealth of datathat challenges the best of nuclear models!
THE ADVENT OF RADIOACTIVE ION BEAMS (RIB): ‘gene pool’ of nuclei on Earth brings a new era
New phenomena observed physics of weakly bound quantum systems
Theorists served with an unprecedented wealth of datathat challenges the best of nuclear models!
● Goals for Nuclear Structure Theory:Identify/investigate many-body methods that will extend to
exotic nucleiGenerate improved effective interactionsMake reliable predictionsGuide experimental effortsPursue interdisciplinary overlaps (e.g., with astrophysics)
THE SCIENCE CASE OF EXOTIC NUCLEI: at the shores of the nuclear landscape
known nucleiknown nuclei
less than 300 stableless than 300 stable
terra incognitaterra incognita
THE SCIENCE CASE OF EXOTIC NUCLEI: at the shores of the nuclear landscape
neutron stars
Stable nuclei:
Unstable nuclei:
protons neutrons
Physics at the neutron drip line: unconventional is normal
NUCLEAR EQUATION OF STATE: from terrestrial matter to compact stars
SCENES FROM THE SKIES:
Watch an artist’s vision of a city-sized neutron star as it ploughs through the skies centered in a disk of hot plasma drawn from its enfeebled red companion star:
… ravenously accreting material from the disk, the neutron star spins faster and faster emitting powerful particle beams and X-ray pulses as it rotates 400 times a second ...
Neutron star movie
FROM QCD TO HEAVY NUCLEI: theory advances building bridges
Effective Field Theories
REMARKS:
•Studies in the past mostly restricted to
stable nuclei with N∕Z= 1 - 1.5
•One of the main thrusts in nuclear physics today: synthesize and study the most exotic nuclear species at the very boundaries of stability
•Field is vital and intensely active, in rapid advance worldwide
•InterdisciplinaryInterdisciplinary sciencescience. . Important for astrophysics and the events that shape the fate of the Cosmos in the core of stars
•This is Physics in ActionPhysics in Action: newest experiments reveal need for an improved many-body theory of the nucleus, which in turn can guide the experimental efforts
REMARKS:
•Studies in the past mostly restricted to
stable nuclei with N∕Z= 1 - 1.5
•One of the main thrusts in nuclear physics today: synthesize and study the most exotic nuclear species at the very boundaries of stability
•Field is vital and intensely active, in rapid advance worldwide
•InterdisciplinaryInterdisciplinary sciencescience. . Important for astrophysics and the events that shape the fate of the Cosmos in the core of stars
•This is Physics in ActionPhysics in Action: newest experiments reveal need for an improved many-body theory of the nucleus, which in turn can guide the experimental efforts
……ultimatelyultimately
‘Bringing Heavens Down to Earth’ !
Credits: this presentation uses pictures and figures taken from the
GSI and RIA links as well as from other websites which provide
information related to the fields of exotic nuclei and astrophysics.
Further information:
• http://www.gsi.de/GSI-Future/cdrhttp://www.gsi.de/zukunftsprojekt/index_e.html The GSI upgrade project
• http://www.orau.org/ria/ The RIA (Rare Isotope Accelerator) project