Prospects for direct CP tests of $hqq$ interactions

Abstract

We study the prospects for probing the CP structure of $hqq$ interactions using the decays of the lightest baryon ${\Lambda }_q$ formed in the quark's hadronization. The low yields of reconstructible events make it unlikely for tests to be performed with the next generation of colliders. In $h\to b\bar{b}\to {\Lambda }_b{\bar{\Lambda }}_b$ decays a CP-sensitive distribution could be measured with a high-luminosity $e^{+}{e}^{-}$ collider, while in both $h\to b\bar{b}\to {\Lambda }_b{\bar{\Lambda }}_b$ and $h\to c\bar{c}\to {\Lambda }_c{\bar{\Lambda }}_c$ decays such a distribution could be measured with a very high luminosity ${\mu }^{+}{\mu }^{-}$ collider. However, we find that only the ${\mu }^{+}{\mu }^{-}$ collider can produce enough $h\to b\bar{b}\to {\Lambda }_b{\bar{\Lambda }}_b$ decays to probe a physical CP asymmetry in the $hbb$ vertex.

Comments: 19 pages, 4 figures