STAR  Computing  Simulation  
Virtual Monte Carlo Implementation in Alice and its potential use in STAR


The STAR VMC application will be based on the virtual Monte Carlo as developed by the ROOT and Alice teams, and in particular on the Alice implementation of the relevant classes.

The reader is also referred to the description of the Alice Event structure.

Review of Classes in AliRoot

The following description of classes presents a combination of code inspection and interpretation of comments in the code, where available. For the most part, the comments are scarce. Keep in mind that the current version of this software is work work in progress, and contains a few archeological layers. The relationship among the various classes and their use are subject to change. Some of the methods spread across classes appear to be redundant. There are approximately 869 classes located in 75 directories.

Below are listed some of the most important ones. An extremely simplified diagram showing the relation between three core classes is shown on the bottom of this page. If the complexity of what's happening in this framework was to be summarized in one sentence, that would be: the stepping method in AliMC interfaces the hit creation and digitization facilities specific for each detector. The energy depositions and other relevant informatin for the hit being created are extracted from the underlying MC engine via the TVirtualMC methods.

Principal components of the Alice VMC system

Last updated by Maxim Potekhin on 11/05/2004