9,217 research outputs found
The mass spectra and decay properties of dimesonic states, using the Hellmann potential
Mass spectra of the dimesonic (meson-antimeson) molecular states are computed
using the Hellmann potential in variational approach, which consists of
relativistic correction to kinetic energy term as well as to the potential
energy term. For the study of molecular bound state system, the Hellmann
potential of the form is
being used. The one pion exchange potential (OPEP) is also incorporated in the
mass calculation. The digamma decay width and decay width of the dimesonic
system are evaluated using the wave function. The experimental states such as
, , , , ,
,, , , ,
are compared with dimesonic states. Many of these states (masses
and their decay properties) are close to our theoretical predictions.Comment: 11 pages, 4 table
Decay and Decoupling of heavy Right-handed Majorana Neutrinos in the L-R model
Heavy right-handed neutrinos are of current interest. The interactions and
decay of such neutrinos determine their decoupling epoch during the evolution
of the universe. This in turn affects various observable features like the
energy density, nucleosynthesis, CMBR spectrum, galaxy formation, and
baryogenesis. Here, we consider reduction of right-handed electron-type
Majorana neutrinos, in the left-right symmetric model, by the WR+ - WR- channel
and the channel originating from an anomaly, involving the SU(2)R gauge group,
as well as decay of such neutrinos. We study the reduction of these neutrinos
for different ranges of left-right model parameters, and find that, if the
neutrino mass exceeds the right-handed gauge boson mass, then the neutrinos
never decouple for realistic values of the parameters, but, rather, decay in
equilibrium. Because there is no out-of-equilibrium decay, no mass bounds can
be set for the neutrinos.Comment: Latex, 16 pages, No figures. Some additions in the text and
references. Conclusions unaffected. To appear in Eur. Phys. J.
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