mjet

Mjet is a term that appears in multiple domains and does not have a single, universally accepted definition. As such, its meaning depends on the context in which it is used.

In high-energy physics, m_jet often denotes the jet mass, defined as the invariant mass of all constituents of a jet. If a jet is composed of N particles with four-momenta p_i, the jet four-momentum is p_jet = sum_i p_i, and the jet mass is m_jet^2 = p_jet^2 = (Σ E_i)^2 − (Σ p_i)^2. The jet mass is used to study the internal structure of jets and to discriminate between quark-initiated and gluon-initiated jets, as well as to identify heavy particle decays contained inside jets. It is computed after applying a jet clustering algorithm such as anti-kT, kT, or Cambridge–Aachen, and depends on the chosen radius parameter and constituent selection.

In computing or software documentation, mjet may appear as an abbreviation, a variable name, or a project label. Without additional context, its exact meaning cannot be determined. If encountered in code, consulting the surrounding documentation or repository naming conventions is recommended.

In other scientific contexts, jets are common in astronomy (astrophysical jets) and meteorology (jet streams). "mjet" may be used informally to denote a mass-bearing jet feature or as a label within a dataset, depending on the source. When faced with the term, identifying the discipline and source is essential to interpreting its intended meaning.