Staff

Baryon number is a strictly conserved quantum number. It is conventionally assumed to be divided equally among the three valence quarks inside each baryon, but this has never been verified experimentally. An alternative model is the baryon junction: a Y-shaped configuration of nonperturbative gluons that is connected to all three valence quarks and carries the baryon number. In this talk we will present two measurements from the STAR experiment which are sensitive the baryon number carrier.

In 1970, Allan Sandage famously described Cosmology as “A search for two numbers”. In the half-century since that description of the field was penned, as Stage III cosmic surveys come to an end and Stage-IV surveys begin taking data, the field finds itself having measured the six parameters of the concordance ΛCDM model at nearly 1% precision. However, different experiments now report different values for two of these parameters – namely the Hubble Constant and the variance of dark matter density fluctuations, S(igma) 8 – at varying levels of significance.

Ultra-relativistic heavy-ion collisions produce a hot and dense QCD matter, called Quark-Gluon Plasma (QGP). Unlike in ordinary matter, quarks and gluons are not confined within short distances but can roam freely over distances larger than the hadronic scale in the state of QGP. Understanding this novel state of matter offers a new way to learn how quarks and gluons bind to form stable particles like the proton.

In this talk, I’ll describe how we use solid-state spin ensembles, magnetic resonance, and quantum sensing techniques to search for axion dark matter in the third-generation CASPEr-e detector. Discovering and characterizing axion dark matter could resolve the longstanding Strong CP Problem, in addition to revealing the identity of dark matter. The Strong CP Problem stems from the puzzling lack of a CP-violating permanent electric dipole moment (EDM) in nucleons.

It was the best of times, it was the worst of times. Just as the classic English novel lends its title well to the spirit of understanding symmetries in the standard model (SM), the opening words also concisely sum up the status of beyond standard model (BSM) physics searches through tests of the fundamental symmetric matrices over the past few decades. Despite the identical mathematical formalism that generates these matrices in the SM, empirically the level of observed mixing within these two are dramatically different.