564 research outputs found
The Use of the Scattering Phase Shift in Resonance Physics
The scattering phase shift encodes a good amount of physical information
which can be used to study resonances from scattering data. Among others, it
can be used to calculate the continuum density of states and the collision time
in a resonant process. Whereas the first information can be employed to examine
the evolution of unstable states directly from scattering data, the second one
serves as a tool to detect resonances and their properties. We demonstrate both
methods concentrating in the latter case on 'exotic' resonances in pi-pi and
pi-K scattering.Comment: Talk given at the International Workshop PENTAQUARK04, July 20-23 at
Spring-8, Japan (new references added
Faraday's law in the presence of magnetic monopoles
We show that if we consider the full statement of Faraday's law for a closed
physical circuit, the standard Maxwell's equations in the presence of electric
and magnetic charges have to include in their integral form a mixed term of the
form where is the magnetic charge density
and the perpendicular component of the velocity
of the electric charge.Comment: 9 page
Pentaquark Resonances from Collision Times
Having successfully explored the existing relations between the S-matrix and
collision times in scattering reactions to study the conventional baryon and
meson resonances, the method is now extended to the exotic sector. To be
specific, the collision time in various partial waves of K+ N elastic
scattering is evaluated using phase shifts extracted from the K+ N --> K+ N
data as well as from model dependent T-matrix solutions. We find several
pentaquark resonances including some low-lying ones around 1.5 to 1.6 GeV in
the P_01, P_03 and D_03 partial waves of K+ N elastic scattering.Comment: Talk given at the International Workshop PENTAQUARK04, July 20-23 at
Spring-8, Japa
Deuteron properties from muonic atom spectroscopy
Leading order () finite size corrections in muonic deuterium are
evaluated within a few body formalism for the system in muonic
deuterium and found to be sensitive to the input of the deuteron wave function.
We show that this sensitivity, taken along with the precise deuteron charge
radius determined from muonic atom spectroscopy can be used to determine the
elusive deuteron D-state probability, , for a given model of the
nucleon-nucleon (NN) potential. The radius calculated with a of 4.3\% in
the chiral NN models and about 5.7\% in the high precision NN potentials is
favoured most by the data.Comment: 14 pages, 2 figure
Possible eta-mesic 3He states within the finite rank approximation
We extend the method of time delay proposed by Eisenbud and Wigner, to search
for unstable states formed by eta mesons and the 3He nucleus. Using few body
equations to describe eta-3He elastic scattering, we predict resonances and
unstable bound states within different models of the eta-N interaction. The
eta-3He states predicted within this novel approach are in agreement with the
recent claim of the evidence of eta-mesic 3He made by the TAPS collaboration.Comment: 10 pages LaTex, 3 figure
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