5,475 research outputs found
Polarized parton distributions in perturbative QCD
We review the main results of next-to-leading order QCD analyses of polarized
deep-inelastic scattering data, with special attention to the assessment of
theoretical uncertainties.Comment: 4 pages Latex, 1 ps figure. Talk given at NUCLEON '99,
Frascati(Italy), June 7-9 199
Status of the Standard Model at the LHC Start
I present a concise review of where we stand in particle physics today.
First, I will discuss QCD, then the electroweak sector and finally the
motivations and the avenues for new physics beyond the Standard Model.Comment: Plenary Talk at the 5th Italian Workshop on p-p Physics at the LHC.
13 pages, no figure
Concluding talk: fundamental lessons and challenges from neutrinos
We present a concise review of the experimental developments on neutrino
mixing and their theoretical implications as presented and discussed at this
Conference. The recent data disfavour many models but the surviving ones still
span a wide range going from Anarchy (no structure, no symmetry in the neutrino
sector) to a maximum of symmetry, as for the models based on discrete
non-abelian flavour groups which can be improved following the indications from
the recent data.Comment: 20 pages, no figures. Talk given at the Pontecorvo 100 Symposium in
honour of Bruno Pontecorvo for the centennial of the birth, Pisa, 18-20
September 2013. arXiv admin note: text overlap with arXiv:1304.5047,
arXiv:1111.6421, arXiv:1210.346
An Overview of Neutrino Mixing
We present a concise review of the recent important experimental developments
on neutrino mixing (hints for sterile neutrinos, large , possible
non maximal , approaching sensitivity on ) and their
implications on models of neutrino mixing. The new data disfavour many models
but the surviving ones still span a wide range going from Anarchy (no
structure, no symmetry in the lepton sector) to a maximum of symmetry, as for
the models based on discrete non-abelian flavour groups.Comment: 6 pages, no figures. Talk given at the Fourth Workshop on Theory,
Phenomenology and Experiments in Flavour Physics, June 2012, Capri, Ital
The Standard Electroweak Theory and Beyond
1. Introduction, 2. Gauge Theories, 3. The Standard Model of Electroweak
Interactions, 4. The Higgs Mechanism, 5. The CKM Matrix, 6. Renormalisation and
Higher Order Corrections, 7. Why we do Believe in the Standard Model: Precision
Tests, 7.1.Precision Electroweak Data and the Standard Model, 7.2.A More
General Analysis of Electroweak Data, 8. Why we do not Believe in the Standard
Model, 8.1.Conceptual Problems, 8.2.Hints from Experiment, -8.2.1 Unification
of Couplings, -8.2.2 Dark Matter, -8.2.3 Neutrino Masses, -8.2.4 Baryogenesis,
9. Status of the Search for the Higgs and for New Physics, 10.ConclusionComment: 59 pages, 9 figures, Lectures given at the Nathiagali Summer School,
Pakistan and the PSI Zuoz Summer School, July - August 200
A Summary from the Theorist's Point of View
1. Introduction - 2. Astrophysics and Cosmology - 3. Neutrino Oscillations -
4. Higgs and New Physics Searches - 5. Flavour Physics and CP Violation - 6.
QCD - 7. Heavy Ion Collisions - 8. OutlookComment: 10 pages, Summary talk given at the IVth Rencontres du Vietnam on
"Physics at Extreme Energies", Hanoi, July 200
The crucial problem: the electroweak symmetry breaking
1. Why we do Believe in the Standard Model
2. Why we do not Believe in the Standard Model
2.1 Conceptual Problems
2.2 Hints from Experiment
2.2.1 Unification of Couplings
2.2.2 Dark Matter
2.2.3 Neutrino Masses
2.2.4 Baryogenesis
3. Status of the Search for the Higgs and for New Physics
4. ConclusionComment: 16 pages, Talk, XI Rencontres de Blois, Frontiers of Matter, 27
June-3 July 199
On the Q^2 Dependence of Measured Polarized Structure Funtions
We analyse the available data on the polarized asymmetries for proton,
neutron and deuteron targets. We use a homogeneous and updated set of
unpolarized structure functions to derive from , and we accurately
correct for the scaling violations in order to obtain with the
same for all values. The contribution to the evolution of a
possible large gluon polarized density is also considered. The implications for
the Ellis-Jaffe and for the Bjorken sum rules are discussed.Comment: 11 pages (LaTex) + 4 figures (topdrawer, included at the end) CERN-TH
7023/9
Neutrino Masses and Grand Unification
We discuss some models of neutrino masses and mixings in the context of
fermion masses in Grand Unified Theories.Comment: Talk, 6th Int. Workshop on TAUP99, 6-10 September 1999, Paris,Franc
Neutrino Tribimaximal Mixing from A_4 Alone
Neutrino tribimaximal mixing is obtained from the breaking of A_4 to Z_3 in
the charged-lepton sector and to Z_2 in the neutrino sector. To enforce this
conflicting pattern, extra particles and symmetries are usually invoked, often
accompanied by nonrenormalizable interactions and even extra dimensions. It is
shown here in a specific renormalizable model how A_4 alone will accomplish
this, with only the help of lepton number.Comment: 8 pages, no figure, reference correcte
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