AMS book

FOREWORD
Advancements in physics are based on the close interplay between experiment and theory.
Advancements in theory are based on the ability of theorists to explain existing experimental results and to predict new phenomena to be confirmed by experiments. Revolutions in physics occur when an experimental result contradicts the theoretical prediction which leads to the creation of new theory.
There is no theory that can disprove an experimental result, whereas a theory, however logical and elegant, cannot be valid if it does not conform to experimental observations. Careful experimentation in physics, such as the discovery of the J particle, the observation of CP violation in K decay, and the discovery of high temperature superconductors have opened up new fields of research in physics. These observations were carried out by experiments even though there was no a priori theoretical interest.

There are two kinds of particles traveling through space: neutral (light rays and neutrinos) and charged particles.

Over the last fifty years there have been many fundamental discoveries in astrophysics from the measurement of photons including the discovery of pulsars, microwave background radiation, binary pulsars, and gamma ray bursts. These discoveries have fundamentally improved our knowledge in physics and astronomy. In recent years, the addition of the ROSAT, AXAF (Advanced X-ray Astrophysics Facility) satellites and the Hubble telescope further enrich our knowledge. The beautiful underground experiments at Gran Sasso (MACRO, KAMIOKANDE and others) have provided us with profound insight on cosmic neutrino physics.

However, there has never been a sensitive measurement of charged cosmic rays. This is because charged particles are absorbed by the earth's atmosphere and therefore they cannot be measured easily on the ground. In addition the charge of cosmic rays can only be identified by their trajectory in the magnetic field. Up to now there has never been a magnetic detector in space.

The Space Station provides unique support for the power, weight and infrastructure required for many precision and long duration experiments. AMS is the first example of a physics experiment on the International Space Station. The purpose of the Alpha Magnetic Spectrometer (AMS) Experiment is to utilize the knowledge and technology learned in particle physics to measure and to identify charged particles as well as very high energy gamma rays to explore new unknown phenomena. This experiment is being carried out by 200 scientists from 12 nations.
In addition to its pure physics goals, this experiment shows that science indeed has no frontiers and scientists from different social and political backgrounds can work together.

The construction of this experiment was made possible through the strong support of NASA, the U.S. Department of Energy (DOE) and the unique contributions of the following individuals: H. Hofer who chairs our AMS Science Board, M. Bourquin and K. Lubelsmeyer who co-chair our AMS International Board, R. Battiston and Y. Galaktionov who co-chair our Astrophysics Board as well as U. Becker, J. Burger, G. Viertel and M. Capell who oversaw the detector integration. R. Sagdeev and J. Trumper shared with us much valuable insight and experience in doing experiments in space. A. de Rujula, J. Ellis, S. Glashow and A. Guth shared with us much of their insight on the current theoretical understanding of astrophysics.

This brochure is intended to provide a description of this experiment in terms of science, technology and international collaboration. I would like to take this this occasion to express on behalf of the AMS Collaboration our appreciation to NASA and the many government leaders and agencies worldwide whose strong support have made this experiment possible. I also want to thank the AMS Administration and Communication Group for putting the brochure together.

Samuel C.C. Ting

INTERNATIONAL SPACE STATION:Assembly Complete
The position of the AMS detector is shown. The ISS program involves the partecipation of 15 cooperating countries: the United States, Canada, Japan, Russia and 11 nations of the European Space Agency (ESA).(NASA)