[Gpd_wg] Joint N*/GPD meeting Fri 10AM -- slides, dial-in info

[Christian Weiss]

Dear Colleagues,


The slides for the presentations at tomorrow's
joint N*/GPD meeting are/will be posted at:

  http://www.jlab.org/~mokeev/react_models_highq2/Meeting_091009/


Remote participants can dial into a polycom phone in
the meeting room. The call-in number is

    1-800-377-8846 (from within the US)
     0800-907-064  (international),

and the conference passcode is

     904683#

(make certain to include the # sign at the end!)


Looking forward to see you tomorrow!

    Ch. Weiss


Christian Weiss
Theory Center
Jefferson Lab
12000 Jefferson Ave
Newport News, VA 23606, USA
Phone: +1.757.269.7013
Fax:   +1.757.269.7002
E-mail: weiss at jlab.org

On Tue, 8 Sep 2009, Christian Weiss wrote:

>
>
> Dear Colleague,
>
>
> As you surely know, an extensive experimental program is planned
> to study the excitation of nucleon resonances at high photon
> virtualities with CLAS12 at JLab. The recently approved experiment
>
>  "Nucleon Resonance Studies with CLAS12"
>  http://www.physics.sc.edu/~gothe/research/pub/nstar12-12-08.pdf
>
> will for the first time determine the N* electrocouplings in the
> region Q2 = 5-10 GeV2 for almost all well-established resonances
> in the pi-N and pi-pi-N channels, providing unique information on
> resonance structure at yet unexplored distance scales.
> A complementary program is under way to study high-Q2 exclusive
> processes in the DIS region, W > 2 GeV, where they can be described
> by a partonic mechanism (GPDs) and give new insight into the
> short-range structure of the ground state. It is clear that there
> are many issues of potentially common interest to both programs,
> such as
>
> ** the possible use of the partonic mechanism to constrain the
>    non-resonant background in hadronic reaction models used
>    to extract N* parameters;
>
> ** the use of finite-energy sum rules and duality concepts in
>    exclusive channels to relate/combine the different descriptions
>    of high-Q2 exclusive production in the resonance (low W)
>    and DIS (high W) regions.
>
>
> Following suggestions by several people we are planning an informal
> meeting between researchers in N* electroproduction and hard exclusive 
> processes, to exchange information, identify issues of common interest,
> and begin their discussion:
>
>   "N* excitation and hard exclusive processes"
>    Friday, 11-Sep, 10:00 -- 13:00, CC F224/225
>
> This first meeting will in particular focus on the phenomenology of
> the production processes in both regions (status of reaction models
> for N* extraction, status of partonic description); a follow-up meeting
> will be devoted to the physical interpretation of high-Q2 resonance
> excitation data, the connection with dynamical models and, possibly,
> lattice QCD calculations. The tentative agenda for the Friday meeting is:
>
>  10:00--10:40   V. Mokeev (JLab): Status of reaction models for
>                 N* excitation analysis and extension to high Q2
>
>  10:40--11:00   Discussion
>
>  11:00--11:30   P. Kroll (Wuppertal U.): Status of partonic
>                 description of exclusive pion production
>
>  11:30--12:00   Discussion
>
>  12:00--12:20   C. Weiss (JLab): Comments on finite-energy sum rules
>                 and duality in exclusive electroproduction processes
>
>  12:20--13:00   Discussion
>
>
> The agenda is very much open; if you would like to make a topical
> contribution please bring it to our attention. In particular, we would
> like to encourage people with expertise in duality and other
> "cross-over" issues to come forward and share their knowledge with us.
> The meeting is intended to be INFORMAL; we want to learn and identify
> interesting issues and will leave ample time for discussion.
>
>
> A summary of the status of the CLAS N* analysis and the reaction models
> used to analyze the data, including references, can be found at:
>  http://www.jlab.org/~mokeev/react_models_highq2/highq2.html
>
>
> People interested in participating in this meeting remotely should
> kindly contact us. There will be a speakerphone in the room (we will
> provide the dial-in information), and the slides can be viewed over
> the web.
>
>
> We hope to see you at the meeting this Friday and are looking forward
> to interesting discussions!
>
>
>   V. Mokeev, R. Gothe, Ch. Weiss
>
>
> Christian Weiss
> Theory Center
> Jefferson Lab
> 12000 Jefferson Ave
> Newport News, VA 23606, USA
> Phone: +1.757.269.7013
> Fax:   +1.757.269.7002
> E-mail: weiss at jlab.org
>