Introduction

An ECFA/DESY 1997 workshop series on the physics and detector requirements at a 500/800 GeV linear collider led to a Conceptual Design Report [1] which summarizes the findings of the study and which forms the starting point for the GEANT description coded in the program Brahms. The detector concept has been further developed and is more fully described in the TESLA technical design report, published in 2001. Brahms is an implementation of the TDR detector. The detectors in V308 reflect the state of developments as of summer 2002.

Brahms is written in FORTRAN and interfaces to GEANT3 [3]. The aim was to produce quickly a working detailed detector simulation to provide a basis for future developments and to cross-check the assumptions made in the fast simulations used for physics analyses. This report describes the version 108 and is intended to act as a catalyst for additions and modifications. It is expected that the author list will continue to grow and that this report, together with Brahms itself, will evolve with time. In this context, the reader is encouraged to criticise both this report and the program itself and to contribute actively to the development of the program.

As FORTRAN and GEANT3 are quickly becoming obsolete future development of a full detector simulation for a detector at a linear collider will shift more and more to GEANT4 and other, more modern languages. the next generation GEANT4 based simulation program within the european linear collider study is MOKKA, developed under the leadership of a group from the Ecole Polytechnique, France.

Nevertheless for the time being Brahms will be maintained as the basis of the simulation software until a full replacement is available.

The user of this program is reminded that the geometry of the TDR detector is fairly complicated, and no warranty is given that the implementation in Brahms is correct. Care should be taken when interpreting results.

The intended user of the code will tend to be interested more in the details of detector design, or in physics studies where simple smearing is not appropriate, rather than in general physics studies. For this reason (and due to time constraints) the code has not been fully optimised for the general user.

A fast simulation program describing the same detector is available from the above mentioned WEB pages. SIMDET V4 is the most recent version and has the TDR detector fully implemented.