A 233 km Tunnel for Lepton and Hadron Colliders

TL;DR

This paper explores the design and technological innovations for multiple collider types within a 233 km tunnel, aiming to advance high-energy physics research with new accelerator configurations.

Contribution

It presents detailed implementation plans for $e^+e^-$, $p ar{p}$, and $$ collider rings using recent technological innovations in a large tunnel.

Findings

Designs for 240 and 500 GeV $e^+e^-$ colliders with advanced beam technologies.

Proposal for a 40 TeV $p ar{p}$ collider using high-field superconducting magnets.

Concept for a 35 TeV muon collider with phase shifting to mitigate neutrino radiation.

Abstract

A decade ago, a cost analysis was conducted to bore a 233 km circumference Very Large Hadron Collider (VLHC) tunnel passing through Fermilab. Here we outline implementations of $e^+e^-$, $p \bar{p}$, and $\mu^+ \mu^-$ collider rings in this tunnel using recent technological innovations. The 240 and 500 GeV $e^+e^-$ colliders employ Crab Waist Crossings, ultra low emittance damped bunches, short vertical IP focal lengths, superconducting RF, and low coercivity, grain oriented silicon steel/concrete dipoles. Some details are also provided for a high luminosity 240 GeV $e^+ e^-$ collider and 1.75 TeV muon accelerator in a Fermilab site filler tunnel. The 40 TeV $p \bar{p}$ collider uses the high intensity Fermilab $\bar{p}$ source, exploits high cross sections for $p \bar{p}$ production of high mass states, and uses 2 Tesla ultra low carbon steel/YBCO superconducting magnets run with liquid neon. The 35 TeV muon ring ramps the 2 Tesla superconducting magnets at 9 Hz every 0.4 seconds, uses 250 GV of superconducting RF to accelerate muons from 1.75 to 17.5 TeV in 63 orbits with 71% survival, and mitigates neutrino radiation with phase shifting, roller coaster motion in a FODO lattice.