Macroscopic strings and quirks'' at colliders

We consider extensions of the standard model containing additional heavy particles (quirks) charged under a new unbroken non-abelian gauge group as well as the standard model. We assume that the quirk mass m is in the phenomenologically interesting range 100 GeV-TeV, and that the new gauge group gets strong at a scale Lambda < m. In this case breaking of strings is exponentially suppressed, and quirk production results in strings that are long compared to Lambda(-1). The existence of these long stable strings leads to highly exotic events at colliders. For 100 eV less than or similar to Lambda less than or similar to keV the strings are macroscopic, giving rise to events with two separated quirk tracks with measurable curvature toward each other due to the string interaction. For keV less than or similar to Lambda less than or similar to MeV the typical strings are mesoscopic: too small to resolve in the detector, but large compared to atomic scales. In this case, the bound state appears as a single particle, but its mass is the invariant mass of a quirk pair, which has an event-by-event distribution. For MeV less than or similar to Lambda less than or similar to m, the strings are microscopic, and the quirks annihilate promptly within the detector. For colored quirks, this can lead to hadronic fireball events with similar to 10(3) hadrons with energy of order GeV emitted in conjunction with hard decay products from the final annihilation.