< List of probability distributions < *Argus distribution *

The** Argus distribution** is a continuous probability distribution introduced by the ARGUS collaboration (**A R**ussian-**G**erman-**U**nited States-**S**wedish Collaboration), which investigated *f-mesons* at Germany’s electron-positron collider ring DORIS II in the late 80s and early 90s [1]. The distribution is especially suited to modeling cases in physics of combinatorial backgrounds with sharp-edged kinematical bounds [2].

## Properties of the Argus distribution

The probability density function (PDF) for the ARGUS distribution in standard form is [4]:

Where

## Uses for the Argus distribution

The Argus distribution has a hard cutoff at x =1, making it a good option for modeling scenarios with sharp boundaries in the data. For instance, it has been applied to the modeling of the invariant mass of hadronic jets in particle physics, wherein a minimum mass defines the jets [5].

This distribution is also useful in representing combinatorial backgrounds in particle physics. These backgrounds arise from random particle combinations and often display sharp edges in their distributions. By using the Argus distribution to model these sharp edges, the accuracy of background estimation can be enhanced.

## The unrelated P.Argus distribution

The choice of the name “Argus” for this distribution is somewhat unfortunate as a search of the literature will bring up many unrelated hits from sources as diverse as marine biology and historical oil holdings!

For example, some researchers have studied the Panulirus *argus* (or *P.Argus*) — the Caribbean spiny lobster. This species of spiny lobster lives on reefs and in mangrove swamps in the western Atlantic Ocean and its spread can be modeled with a “P.Argus” distribution — completely unrelated to the Argus distribution used in physics.

Another completely unrelated search entry pertains to the Argus Natural Gas Company, which was eventually consolidated with Enron.

“Not content with this state of affairs, Northern, Peoples,

From Ritchie’s Integration of Public Utility Holding Companies, 1954, p.128

and Argus sought permission to retain the Argus distribution

properties within Northern’s integrated system”

## References

[1] ARGUS collaboration. Albrecht, H. et al. Search for hadronic b->u decays. Phys. Lett. B241, 278-282 (1990) 3.

[2] Lista, L. (2017). Statistical Methods for Data Analysis in Particle Physics. Springer.

[3] Image: Shiyu Ji, CC BY-SA 4.0 https://creativecommons.org/licenses/by-sa/4.0, via Wikimedia Commons

[4] Clustering package (`scipy.cluster`

) scipy.stats.argus# https://docs.scipy.org/doc/scipy/reference/generated/scipy.stats.argus.html

[5] Physics with ARGUS. Retrieved August 17, 2023 from: https://bib-pubdb1.desy.de/record/491246/files/desy96-015.pdf