Glossary

AMBIGUITY

If an event is a PRIMARY for more than one ASSOCIATION, then this is an AMBIGUITY. TCA can record the level of such ambiguities but cannot, at least at present, measure other ambiguities i.e. multiple ASSOCIATIONs in which an event is not the PRIMARY.

ASSOCIATION

When a set of events together satisfy the conditions specified in the current TCAR bank they form an ASSOCIATION.

CANDIDATE

The current TCAR may specify conditions that refer only to a single MEMBER NUMBER. For example:-

nhit_1       equals            nhit_1: 30. 30.;

Such conditions determine whether an event can play the role of that MEMBER NUMBER in any ASSOCIATION. The collection of all such tests is called the CANDIDATE test, and an event that passes is called a CANDIDATE for that MEMBER NUMBER. So, for example, events can be PRIMARY CANDIDATEs or SECONDARY CANDIDATEs. Any event that fails all CANDIDATE tests is ignored.

CORRELATION

If a process produces a cascade of events leading to multiple detector triggers, then study of those multiples will show CORRELATIONs. TCA attempts to find examples of these multiples by forming ASSOCIATIONs between all possible sets of events.

MEMBER NO.

In an ASSOCIATION, each event is given a unique MEMBER NO. running from 1 to the MULTIPLICITY. Member 1 is called the PRIMARY and member 2 the SECONDARY. In a TCAR bank, a member's variables is accessed by adding the MEMBER NO. as a suffix to the variable name e.g. nhit_1 refers to the NHIT variable of the PRIMARY event.

MULTIPLICITY

The MULTIPLICITY of an ASSOCIATION is number of events it contains. Currently TCA can only deal with a MULTIPLICITY of 2, but could be extended.

PRIMARY

The PRIMARY is the first MEMBER NO. in an ASSOCIATION. To some extent the terms PRIMARY and SECONDARY are interchangeable. In general the user should select, as the PRIMARY, the type of event that will produce the smallest number of false PRIMARY CANDIDATEs.

SECONDARY

The SECONDARY is the second MEMBER NO. in an ASSOCIATION.