[Clas_hadron] Talk on April APS meeting

[gleb at jlab.org]

Dear clas hadron group members,

I would like to make talk on nearest APS meeting in Denver.
Talk title is "Electroproduction
Cross Sections off Protons in the Second Resonance Region"
Abstract of my talk available here:
http://www.jlab.org/Hall-B/secure/hadron/abstracts/2012/APS_April_13-16_gleb.pdf
and also posted below this message. I will be appreciate to any comment
and suggestions.







G.~V.~Fedotov$^{1,3}$, R.~W.~Gothe$^{1}$ and V.~I.~Mokeev$^{2,3}$ for the
CLAS Collaboration

In this talk we present preliminary $\pi^{+} \pi^{-} p$
electroproduction cross sections off
protons in the kinematical area of $W$ from  1.4  to 1.8~GeV and $Q^{2}$
from 0.4 to 1.1~GeV$^{2}$. Our kinematical coverage in part overlap
with previous CLAS measurements\cite{Ripani:2002ss}, but offers more than
a factor six
finer binning in $Q^{2}$.

The physics analysis of these data within the framework of the JM model
\cite{2012sha,Mokeev:2008iw} will allow us to
determine the electrocouplings and the partial $\pi \Delta$, $\rho p$
decay widths of several high
lying nucleon resonances S$_{31}$(1620), S$_{11}$(1650),
F$_{15}$(1685), D$_{33}$(1700), P$_{13}$(1720) and to further explore the
evidence for the 3/2$^{+}$(1720)
candidate-state.

Analysis of the single pion electroproduction data measured with CLAS in
the aforementioned
kinematic region is in progress.
Single and charged double pion exclusive channels are major contributors to
the meson electroproduction in the N* excitation region with different
non-resonant
mechanisms. A successful description of all observables in these exclusive
channels
with consistent N* electrocouplings will offer evidence for the reliable
evaluation of these
fundamental quantities.