Accessing the deuteron source with pion-deuteron femtoscopy in Pb-Pb collisions at (Formula Presented)

Femtoscopy of nonidentical particle pairs has been instrumental for precision measurements of both two-particle sources and the final-state interactions in high-energy elementary and heavy-ion collisions. The majority of measurements assessing the source properties are based on identical particle pairs, providing direct access to the characteristics of the single-particle source. The work in this paper demonstrates, via femtoscopy measurements of charged pion-deuteron pairs in Pb-Pb collisions at <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"> <a:mrow> <a:msqrt> <a:msub> <a:mi>s</a:mi> <a:mi>NN</a:mi> </a:msub> </a:msqrt> <a:mo>=</a:mo> <a:mn>5.02</a:mn> </a:mrow> </a:math> TeV, the feasibility of accessing the characteristics of the single-particle femtoscopic source by using particle pairs with large mass differences such as pions and deuterons. The first experimental results of the measurement of deuteron source sizes in ultrarelativistic heavy-ion collisions are presented. The results show good agreement with the trend derived from other charged hadrons such as pions, kaons, and protons as a function of transverse mass, indicating similar source properties.