Optimization of Integrated Luminosity of the Fermilab Tevatron Collider

TL;DR

This paper presents a strategy to optimize the integrated luminosity of the Fermilab Tevatron collider by modeling store parameters, resulting in a 35% improvement in luminosity through stash size optimization and operational improvements.

Contribution

The paper introduces a simple model for optimizing collider luminosity by adjusting stash size, leading to significant operational efficiency gains.

Findings

Approximately 35% increase in integrated luminosity achieved.

Optimal stash size range predicted by the model.

Operational improvements include reducing shot-setup time and beam-beam effects.

Abstract

We present the strategy which has been used recently to optimize integrated luminosity at the Fermilab Tevatron proton-antiproton collider. We use a relatively simple model where we keep the proton intensity fixed, use parameters from fits to the luminosity decay of recent stores as a function of initial antiproton intensity (stash size), and vary the stash size to optimize the integrated luminosity per week. The model assumes a fixed rate of antiproton production, that a store is terminated as soon as the target stash size for the next store is reached, and that the only downtime is due to store turn-around time. An optimal range of stash sizes is predicted. Since the start of Tevatron operations based on this procedure, we have seen an improvement of approximately 35% in integrated luminosity. Other recent operational improvements have been achieved by decreasing the shot-setup time and by reducing beam-beam effects by making the proton and antiproton brightnesses more compatible, for example by scraping protons to smaller emittances.