88,650 research outputs found
Little Higgs searches at LHC
A new method of solving the hierarchy problem in the SM has been proposed.
This method leads to the so-called "Little Higgs" models. The ATLAS experiment
at LHC has undertaken studies of the new particles predicted by these model: a
heavy top quark, heavy gauge bosons and additional Higgs bosons. Simulations of
their decays have been carried out. The sensitivity of the ATLAS experiment to
discover these new particles is discussed.Comment: 8 pages, 8 figures, XXXIXth Rencontres de Moriond, La Thuile(2004
Nuclear shape coexistence in Po isotopes: An interacting boson model study
Background: The lead region, Po, Pb, Hg, and Pt, shows up the presence of
coexisting structures having different deformation and corresponding to
different particle-hole configurations in the Shell Model language.
Purpose: We intend to study the importance of configuration mixing in the
understanding of the nuclear structure of even-even Po isotopes, where the
shape coexistence phenomena are not clear enough.
Method: We study in detail a long chain of polonium isotopes, 190-208Po,
using the interacting boson model with configuration mixing (IBM-CM). We fix
the parameters of the Hamiltonians through a least-squares fit to the known
energies and absolute B(E2) transition rates of states up to 3 MeV.
Results: We obtained the IBM-CM Hamiltonians and we calculate excitation
energies, B(E2)'s, electric quadrupole moments, nuclear radii and isotopic
shifts, quadrupole shape invariants, wave functions, and deformations.
Conclusions: We obtain a good agreement with the experimental data for all
the studied observables and we conclude that shape coexistence phenomenon is
hidden in Po isotopes, very much as in the case of the Pt isotopes.Comment: To be published in Physical Review C. arXiv admin note: text overlap
with arXiv:1312.459
The influence of intruder states in even-even Po isotopes
We study the role of intruder states and shape coexistence in the even-even
Po isotopes, through an interacting boson model with configuration
mixing calculation. We analyzed the results in the light of known systematics
on various observable in the Pb region, paying special attention to the
unperturbed energy systematics and quadrupole deformation. We find that shape
coexistence in the Po isotopes behaves in very much the same way as in the Pt
isotopes, i.e., it is somehow hidden, contrary to the situation in the Pb and
the Hg isotopes.Comment: Contribution to the Nuclear Structure and Dynamics 2015 (Portorose,
Slovenia) proceeding
Classical calculations of charge transfer cross sections
Calculations of charge transfer cross section
Classical approximation for ionization by heavy particle impact
Classical binary approximation for ionization by proton impac
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