gamma-gamma collider meeting
                        ============================
                        7-May-2002,   Fermilab

present:
Mayda Velasco
Jeff Gronberg
Sahal Jacoob
Stefan Soeldner-Rembolt
Heather Logan
David Asner
Michel Schmitt

======================================================================
Mayda -- The Overall Plan
         ===============

Mayda presented suggestions for how to get the most relevant
work done in time for the LC conference in Korea.  There was
much discussion and many suggestions (which I will not try to
reproduce here).  A rough consensus can be summarized as follows:

 h->bbbar     NLO treatment is finished: are there any important
              issues for the light Higgs?  We need to establish better
              the visibility of the heavier Higgs states in the MSSM,
              and back up our claims that linear polarization can be
              used to identify the states.

 h->WW        This channel still is in progress: QCD backgrounds
              remain to be estimated, and these require four-fermion
              generators.

 h->gaga      done.  A paper is in the draft stage.

 h->leptons   Mayda looked into this: muons and taus are both
              impossible.
 

 h->gaZ,ZZ    Mayda's estimates say these channels are promising.
              She is waiting for the 4-fermion generator to make
              progress.  Sahal will work with Steve to get it done.
              The gaZ channel, when combined with the gaga channel,
              is expected to help tie down the stop sector, especially
              if there are CP violations.  It might be possible to
              extract the total width from h->ZZ by combining with
              measurements from an e+e- collider.

 gaga->H+H-   This looks promising, but no real work has been done
              yet.  This is a priority item.

 gaga->csH-   This may be quite hard, due to the low cross section.
              It could be investigated as part of the H+H- study.

 charginos    People were pessimistic that a gaga collider would
              be able to compete with e+e-.  However, it was pointed
              out that the gaga cross section depends only on the
              electric charge, and hence is independent of the field
              content of the charginos.  This may prove useful when
              combined with e+e- measurements.

Other points that came up in the discussion:

1- We should send an abstract for ICHEP in Amsterdam.
   (Deadline: May 15)

2- Tom Rizzo is very interested in studying possible signals for
   extra dimensions at a gamma-gamma collider.

3- Similarly, Joanne Hewitt is interested in investigating signals
   for radions (size moduli of extra dimensions).

4- David reports that a design for a 2 or 3 micron laser exists.

5- It was agreed that we should start drafting a contributed document
   for Korea, irrespective of whether any of us gives a presentation.
   One possibility would be a `draft run plan' which outlines
   specifically which physics one would do with, e.g. CLICHE.
   The important point is to draft the paper soon, even if many
   details only show up toward the end of the summer.

Upcoming conferences and workshops:
  Santa Cruz  (Jeff)    27-29 June
  ICHEP - Amsterdam     24-31 July
  ECFA - Tokyo        July
  S.Korea (Mayda)     late August