Synopsis: A new partner for the top quark?

Researchers propose that the supersymmetric partners of the top and bottom quarks are spin 1 instead of spin 0.
Synopsis figure
Illustration: Alan Stonebraker

Supersymmetry is a proposed extension of the Standard Model of particle physics in which each elementary particle has a partner—called a superpartner—with the opposite spin statistics. The idea addresses some key theoretical concerns about the Standard Model and provides a compelling candidate particle for the dark matter. If they exist, the superpartners in most models with these properties should be detectable at the Large Hadron Collider (LHC).

In most of the supersymmetric models proposed so far, the spin-1/2 fermion particles that make up matter—the quarks and the leptons—have heavy spin-0 superpartners. The spin-1 particles of force, like the photon, have heavy spin-1/2 superpartners. Writing in Physical Review Letters, Haiying Cai, Hsin-Chia Cheng, and John Terning of The University of California, Davis, consider an alternative possibility in which the superpartners of the spin-1/2 top and bottom quarks are spin 1 instead of spin 0.

Aside from providing a possible explanation for why the top quark is so heavy, this model predicts experimental signatures that are different from other models and could be measured at the LHC (notably, an enhanced cross section for the top quark’s superpartner). It is important to have a panoply of possible signatures to compare to what is actually measured at the LHC. – Robert Garisto


Announcements

More Announcements »

Subject Areas

Particles and Fields

Previous Synopsis

Next Synopsis

Related Articles

Synopsis: Testing Quantum Physics with Neutrinos
Quantum Physics

Synopsis: Testing Quantum Physics with Neutrinos

An experiment similar to the Bell inequality test confirms that neutrino oscillation is a quantum physics effect that is incompatible with alternative classical models. Read More »

Viewpoint: Of Gluons and Fireflies
Nuclear Physics

Viewpoint: Of Gluons and Fireflies

Improved models of gluon fluctuations within protons have been developed and applied to particle collision data, pointing to strong gluon fluctuations at high energies. Read More »

Synopsis: Trailing the Photons from Neutron Decay
Nuclear Physics

Synopsis: Trailing the Photons from Neutron Decay

A high-precision measurement of the photons emitted by neutron decays brings researchers closer to a new test of the standard model. Read More »

More Articles