Transcript A Z X , A is atomic mass number, Z is atomic number, A - Z is number of neutrons in the.

A
Z
X , A is atomic mass number, Z is atomic number, A - Z is number of neutrons in the nucleus.
isotopes : nuclei have the same Z but different A
isotones : nuclei have the same A - Z but different Z
isobars : nuclei have the same A but differnt Z
Proton numbers
Gamma decay : ZAX *  ZA X  
Beta decays : ZAX  ZA1Y  e   e , ZAX  ZA1Y  e   e , ZAX  e   ZA1Y  e
Alpha decay : ZAX  AZ--42Y  24He
Neutron numbers
Nuclear Binding Energy
Nuclear Fusion
Solar Model
Nuclear Fission and Chain Reaction
Standard Model
Breaking News from CERN
Have we discovered Higgs?
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Challenges in Physics
 Confinement QCD


QCD at different energies
Lattice QCD
Chiral perturbation theory
 New physics beyond the Standard
Model (SM)
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

New sources of symmetry violation
Dark matter
Dark energy
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“Vector Portal” to Dark Sector
1.
Dark photon A’
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- e F mn Fmn' Kinetic mixing and U(1)’
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2. Dark leptophobic B-boson
(dark ω, γB , or Z’): 1 gB qg m qBm
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Gauged baryon symmetry U(1)B
Early studies by Lee and Yang, Phys.Rev.,98
(1955) 1501; Okun, Yad.Fiz., 10 (1969) 358,
the stability of baryonic and dark
matter
a unified genesis of baryonic and dark
matter
a natural framework for “Strong CP
problem” in QCD
the mB < mp region is strongly
constrained by long-range forces search
exp. ; the mB > 50GeV has been
investigated by the collider exp.
Most A’ searches are through its
decay to l +l - relying on the
leptonic coupling of new force
GeV-scale domain is nearly untouched,
a discovery opportunity!
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Striking signature for B-boson in η decay
 B production:
A.E. Nelson, N. Tetradis, Phys. Lett., B221, 80 (1989)
 B decays: B0 in 140-600 MeV mass range
B+0
Search for a resonance
peak of 0 for
mB ~140-550 MeV
S. Tulin,
Phys.Rev., D89, 14008
(2014)
 G(h ® p
gg ) ~ 0.3eV
0
highly suppressed SM background
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Jlab Eta Factory (JEF) Experiment (B0 )
 A stringent
constraint on the
leptophobic B-boson
in 140-550 MeV
range.
 A positive signal of B
in JEF will imply a new
fermion with a mass
up to a few TeV due
to electro-weak
anomaly cancellation.
 Future ’ experiment
will extend the
experimental reach
up to 1 GeV
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C Invariance
 Maximally violated in the weak
force and is well tested.
 Assumed in SM for electromagnetic
and strong forces, but it is not
experimentally well tested (The
current constraint:  1 GeV)
C Violating η neutral decays
Final
State
Branching Ratio
(upper limit)
3γ
< 1.6•10-5
π0γ
2π0γ
 EDMs place no constraint on CVPC
in the presence of a conspiracy or
new symmetry; only the direct
searches are unambiguous.
(M. Ramsey-Musolf, phys. Rev., D63, 076007
(2001); talk at the AFCI workshop
)
<
9•10-5
Gammas
in Final
State
3
< 5•10-4
5
3γπ0
Nothing
published
3π0γ
< 6•10-5
3γ2π0
Nothing
published
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Experimental Improvement on η→3γ
 SM contribution:
BR(η→3γ) <10-19 via P-violating
weak interaction.
 A new C- and T-violating, and
P-conserving interaction was
proposed by Bernstein, Feinberg
and Lee Phys. Rev.,139, B1965 (1965)
Proj. JEF
 A calculation due to such new
physics by Tarasov suggests:
BR(3)< 10-2
Sov.J.Nucl.Phys.,5,445 (1967)
 A new investigation by M. R-M and
two Ph.D. students is in progress
Improve BR upper limit by one
order of magnitude to directly
tighten the constraint on
CVPC new physics
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