Table Of Contenteditors
Maria-Novella Kienzle-Focacci
Maneesh Wadhwa
Photon 2001
International Conference on the Structure and Interactions of the Photon
Including the 14th International Workshop on Photon-Photon Collisions
Photon 2001
International Conference on the Structure and Interactions of the Photon
Including the 14th International Workshop on Photon-Photon Collisions
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editors
Maria-Novella Kienzle-Focacci
University of Geneva, Switzerland
Maneesh Wadhwa
Basel University, Switzerland
Photon 2001
International Conference on the Structure and Interactions of the Photon
Including the 14th International Workshop on Photon-Photon Collisions
Ascona, Switzerland 2-7 September 2001
V |b World Scientific
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A catalogue record for this book is available from the British Library.
PHOTON 2001
Proceedings of the International Conference on the Structure and Interactions of the
Photon, Including the 14th International Workshop on Photon-Photon Collisions
Copyright © 2002 by World Scientific Publishing Co. Pte. Ltd.
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ISBN 981-238-053-1
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PREFACE
PHOTON2001, an International Conference on the Structure and Inter
actions of the Photon, organised by the University of Geneva, was held at the
Centro Stefano Pranscini on Monte Verita, Ascona, Switzerland, from the 2nd
to the 7th of September 2001.
The conference is the 14th in a series that started in Paris in 1973. The
conferences were originally devoted entirely to the physics of photon-photon
collisions, but since 1995 the scope has been extended to include also single
photon interactions which have been extensively studied in recent years at the
HERA ep collider at DESY, Hamburg.
As is customary in this series, only plenary talks were given. These were
grouped into sessions on: Photon Structure (8), Jets and Inclusive Hadron
Production (13), Charm and Beauty Production (10), Total Cross-Sections
and Diffraction (16), Resonances and Exclusive Channels (23) and Future
Projects and Related Topics (8). The number of 15 minute talks given in
each session is shown in parentheses. Out of a total of 78 talks, 58 were ex
perimental and 20 theoretical. Conference summary talks of 45 minutes were
given by Armin Boehrer (experiment) and Maria Krawczyk (theory). The
majority of new experimental results presented were from LEP and HERA,
but important contributions came also from detectors at lower energy high
luminosity colliders such as BELLE and CLEO. Particularly impressive were
the huge statistics of the preliminary data on gamma gamma collisions from
BELLE. Other experimental highlights were new experimental results from
HERA and LEP (open b-quark production in 7p and 77 collisions and inclu
sive production of IT0 at high pr in 77 collisions) that seem to pose a serious
challenge to the predictive power of perturbative QCD. Hints for the pro
duction of the so-far-unobserved 775 meson were shown. The first results in
coherent photon-photon and photon-pomeron collisions from the RHIC heavy
ion collider at Brookhaven were presented. In the future, important results
in this domain are expected from heavy ion collisions in the LHC collider at
CERN. In two other talks the possibility for detection of tagged 77 interac
tions in pp collisions at the LHC were reviewed. The current status of the
real photon collider within the TESLA linear electron accelerator project was
also described.
The Centro Stefano Franscini is situated in 'sub-tropical Switzerland' on
the sunny western shore of Lake Maggiore. In the early years of the 20th
Century, the summit of Monte Verita was home to a commune seeking an
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VI
outdoor way of life, a vegetarian diet, simplicity, nature and free love. One
visitor during this period, seeking therapy for a nervous disorder was Hermann
Hesse. Other visitors to Ascona around this time included Carl Gustav Jung,
Erich Maria Remarque, Paul Klee, Hans and Sophie Tauber Arp and Alexi
Jawlensky. In 1927 the Monte Verita Hotel was built by Emil Fahrenkamp.
During this period, Ascona became an important meeting point for many
artists of the 'Bauhaus' school. After the second world war, Jorge Semprun
could restore his health in the Ascona and Locarno surroundings. In 1956
Baron von der Heydt, the then owner of Monte Verita, left the property to
Canton Ticino. In 1989 a private foundation including Canton Ticino, the
Town Council of Ascona and the Swiss Federal Institutes of Technology in
Lausanne and Zurich was established with the aim of creating a cultural and
scientific centre on Monte Verita. In 1992 the present Centro Stefano Franscini
was founded.
The 90 participants at the Conference were able to benefit the excellent
conference facilities, clear air, splendid views and good food provided by the
Centro Stefano Franscini. During the excursion to the Brissago Islands, they
were also able to appreciate the fine weather, a very interesting visit to a
unique botanical garden, and the convivial Conference Dinner sandwiched
between two memorable concerts of Good Time Jazz provided by local musi
cians.
We should like to thank Claudia Lanfranchi for the warm and efficient
organization of our life in the Center. Shivani Wadhwa and Peggy Argentin
for their continous kindness and Patrick Deglon for his ability in solving com
puters problems.
The sponsorship of the Conference by Hewlett-Packard, Victorinox,
the Swiss National Science Foundation, CERN, ETHZ and the Societe
Academique de Geneve is gratefully acknowledged.
John H. Field
Maria Novella Kienzle-Focacci
Maneesh Wadhwa
COMMITTEE
International Committee Programme Committee
S. J. Brodsky (SLAC) M.N. Kienzle-Focacci (Geneva)
M. Erdmann (Karlsruhe) C. Amsler (Zurich)
F. C. Erne (NIKHEF) R. Eichler (PSI)
V. S. Fadin (Novosibirsk) Z. Kunszt (ETHZ)
J. H. Field (Geneva) M. Pohl (Geneva)
D. Hitlin (CALTECH) L. Tauscher (Basel)
S. Iwata (KEK)
F. Kapusta (LPNHE Paris)
Local Organising Committee
U. Karshon (Weizmann)
R. Klanner (DESY)
M.N. Kienzle-Focacci (Chairwoman,
M. Krawczyk (Warsaw)
Geneva)
D. J. Miller (UC London)
P. Achard (Geneva)
H. P. Paar (UC San Diego)
P. Deglon (Geneva)
G. Pancheri (Frascati)
M. Wadhwa (Basel)
S. Soldner-Rembold (CERN)
P. Argentin (Secretary, Geneva)
V. I. Telnov (Novosibirsk)
C. Lafranchi (CSF)
A. Wagner (DESY)
P. M. Zerwas (DESY)
VII
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CONTENTS
Preface v
Committee vii
1 Photon Structure
Measurement of the Hadronic Photon Structure Function F% at LEP2 3
R. J. Taylor
Study of the Hadronic Photon Structure Function with the DELPHI
Detector at LEP 7
I. Tyapkin
Measurement of the Charm Structure Function of the Photon at LEP 14
A. Csilling
New Analysis of LO Parton Distributions of the Real Photon —
Preliminary Results 19
P. Jankowski
The Structure of Real Photons at HERA 23
A. Valkdrovd
Structure of Virtual Photons at HERA 29
K. Sedldk
Charm and the Virtual Photon at HERA 35
B. J. West
Summary of the Structure Function Session at Photon 2001 39
R. Nisius
2 Jets and Inclusive Hadron Production
Inclusive 7r° and K^ Production in Two-Photon Collisions at LEP 49
P. Achard
Fragmentation in Diffractive Deep Inelastic Scattering at HERA 53
D. Traynor
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