Mayda Velasco, Sven Heinemeyer, Andre de Gouvea, Steve Mrenna, Ayres Freitas,
Bob Oakes, Jeff Gronberg, Victoria Martin, Michal Szleper, Armin Apyan,
Michael Schmitt, Jack Gunion (by phone), Heather Logan (by phone),
David Asner (by phone, morning)
 

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gamma-gamma collider physics (morning)
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We submitted to Lepton-Photon 2003 a preprint with more details
on gamma-gamma collider as Higgs factory.  The title is:

"Complementarity of a Low Energy Photon Collider and LHC Physics"

and is available at http://arxiv.org/ps/hep-ph/0308103.

We would like to finalize this work and submit it to a journal.  The
purpose for this paper is that we extend the physics arguments in favor of
pursuing a low energy gg-collider, either at CLICHE, or possibly as an
adjunct to an upcoming LC.  We will include check on the complementarity
with LHC only.

We are aiming at having the paper ready by the end of Sept.

The status of the analysis of each of the topics was discussed
in detail:

* Standard Model:  H-->bb, W^*W and GammaGamma are as disccused in
http://arXiv.org/abs/hep-ex/0111056.  As discussed, by Michal we
are in the process of adding Z^*Z. The backgrounds being considered
are gg-->4fermions as obtained from WHIZARD and  gg--> ZZ.  At the
moment the selection for in the bbbb mode does not look promising,
but there are several cuts that can still be applied. But modes
with leptons have a good signal to background ratio.
In order to generate more 4-fermion MC, Victoria will make interface
between the gg--> ZZ  generator, given to use by Thomas Hahn,
and PANDORA faster.
- the motivation of adding ZZ is that in the MSSM it should behave
like WW  and it will be an important channel when we are looking
and radion-higgs mixing for a Higgs that is heavier.
 
* MSSM: We tried to do H-->bb in the MSSM using the new utilities provided
by PANDORA, however, the results were not reliably due to the lack of
radiative correction.  Steve M.  has pointed out that we can do all
this studies properly using Pythia, and the Pythia-CAIN intereface
is also available.  That is how we will do it.
Heather L. and Sven H., will produce the corresponding theoretical
work to check how sensitive we will be to the MSSM and the complementarity
with the LHC.
 
 

* Complex MSSM:  Sven  H.  is currently working on finalizing this
work.  All tools are now available, so results should be finalized
soon, and then we will compare with what we have already found for the
NMSSM.

* Littles Higgs:  Heather provided the full description of the
model, but the comparison with the  LHC was missing.  To come soon :-)

* Radion-Higgs mixing: Jack G.  has also finalized the theoretical
work.  We need the  experimental studies for WW, and ZZ at higher
masses.  In the case of WW we will add the gg-->4fermions as potential
backgrounds.

* Machine updates:  Jeff and Mayda will contact the CLIC machine people
to update the CLICHE capabilities.  We will include a 4-module design
instead of 2-modules to avoid the tripler and check a gg-factory with
linearly polarized beams.
 

minutes contributed by M.V.