35 research outputs found
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 1/Lambda. The existence of these long stable strings leads to
highly exotic events at colliders. For 100 eV < Lambda < 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 <
Lambda < 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 < Lambda < m the
strings are microscopic, and the quirks annihilate promptly within the
detector. For colored quirks, this can lead to hadronic fireball events with
10^3 hadrons with energy of order GeV emitted in conjunction with hard decay
products from the final annihilation.Comment: Added discussion of photon-jet decay, fixed minor typo
A novel large plasmid carrying multiple β-lactam resistance genes isolated from a Klebsiella pneumoniae strain
10.1046/j.1365-2672.2000.01069.xJournal of Applied Microbiology8861038-1048JAMI