Organizers:  M. Chadwick, F. Dietrich, A. Koning, A. Kerman, G. Reffo

Sponsors:  ECT*, Trento
           Lawrence Livermore National Laboratory
           Los Alamos National Laboratory
           Centro Dati Nucleari, ENEA, Bologna


Scope of the Meeting

The purpose of this meeting is to gather a small number of experts to
identify outstanding problems in multistep reaction theories using
quantum mechanical approaches, and to develop a plan for attacking
them.  These problems include both fundamental issues in the
formulation of multistep theories and practical issues in implementing
them.  The focus will be on multistep direct (MSD) theories; multistep
compound reactions will be included where connections to MSD are
important.  In addition, related approaches that shed light on the
applicability and limitations of MSD will be considered at the
meeting.  The entire energy range in which quantum multistep reactions
using only nucleon degrees of freedom are dominant will be discussed;
i.e., up to energies of a few hundred MeV.

The meeting will be held in the framework of Collaboration Meetings at
the ECT*.  These are meetings that last for a few days and involve a
small number of participants (less than about 20).  For meetings of
this type the ECT* makes their facilities available, but travel and
living expenses are covered by the participants.

The structure of the meeting will be informal, with a strong emphasis
on working groups that will address the topics indicated below.  There
will be no published proceedings from the meeting, but we expect that
viewgraphs of talks (on a voluntary basis) and reports of the working
groups will be distributed to the participants.

Preliminary Outline of Topics to be Addressed:

I.  Fundamental Issues
      A.  Formulation of the various approaches (FKK, Tamura, Weidenmuller et
          al.)
      B.  Distorted-wave boundary value question in FKK
      C.  Connection to high-energy multiple-scattering approaches
      D.  Connection to classical and semiclassical models (e.g. intranuclear
          cascade, exciton,  SCDW, QMD)
      E.  The role and nature of the effective interaction (real vs. complex;
          connection with t-matrix and t-rho folding approaches;  energy
          dependence)
      F.  The nature of the intermediate states
      G.  Linkage between multistep direct and multistep compound processes
      H.  Connection to DWBA and DWIA treatments of inelastic scattering
          and charge exchange
II.  Implementation Issues
      A.  Level densities and structure effects
            Shell effects in the level densities
            Inclusion of RPA and other quantal approaches to collectivity
            Use of particle-hole intermediate states from the shell model
            Use of semiclassical (hydrodynamic) collective intermediate
states 
            Extension of level densities into the continuum
      B.  Treatment of multiple particles in the continuum (cascading)
      C.  Optical potentials for multistep reactions
      D.  Connection between the strength parameter in FKK and what is
          expected of effective interactions
III.  Identification of Key Experiments

We hope that you will accept our invitation to attend this meeting.
Please reply to Mark Chadwick at the E-mail address below, indicating
whether you definitely expect to attend the meeting; may possibly
attend; or will not be able to attend. Please also send us information
on your contact address, fax number, and email address.

In the first two cases, please also give an indication of the topics
you would like to address.  Also, please do not hesitate to get in
touch with the meeting organizers for more information or to give them
suggestions on how to make the meeting most effective.

E-mail addresses of the organizers are:
     M. Chadwick:    mbchadwick@lanl.gov
     F. Dietrich     dietrich2@llnl.gov
     A. Koning       koning@ecn.nl
     A. Kerman       kerman@mitlns.mit.edu
     G. Reffo        reffo@nudace.arcoveggio.enea.it



With best wishes,

Mark Chadwick, Frank Dietrich, Arjan Koning, Arthur Kerman, and Gianni Reffo