Charm and multi-charm baryon measurements via strangeness tracking with the upgraded ALICE detector

Abstract

We present a new method for detection of multiply charmed baryons via their decays into strange baryons, using `strangeness tracking'. This method makes use of the state-of-the-art upgraded silicon detectors in ALICE during Runs 3, 4 and beyond will enable the novel possibility of tracking strange hadrons directly before they decay, leading to a very significant improvement in impact-parameter resolution. In this work, we will discuss how this new technique will be crucial to distinguish secondary strange baryons originating from charm decays from primary strange baryons. This is a particularly interesting possibility for the $\Omega^{-}$ baryon coming from $\Omega_{\rm{c}}^{0}\rightarrow\Omega^{-}\pi^{+}$ decays, since there is no other relevant feeddown source for $\Omega^{-}$. This, in turn, means that the main $\Omega^{-}$ background for the $\Omega_{\rm{c}}$ measurement will point most accurately to the primary vertex, unlike pions or protons from other charm baryon decays. We will illustrate the achievable performance of strangeness tracking for the Run 3 configuration of ALICE with the upgraded Inner Tracking System, which is fully instrumented with silicon pixel detectors. Moreover, we will discuss the potential of this technique in a future experiment with an extensive silicon tracking detector with a first layer very close to the interaction point. Finally, we will also cover other potential major applications of strangeness tracking, including measurements of hypernuclei such as the $^{3}_{\Lambda}\rm{H}$.