The STAR Collaboration reports measurements of the collision energy dependence of hypertriton (^3_ΛH) transverse momentum spectra and p ₓ-integrated yields at mid-rapidity (|y|<0. 5) in Au+Au collisions at 11 collision energies between 3. 2 and 27\, GeV. The measured ^3_ΛH yields and ^3_ΛH/Λ yields ratio in central collisions increase strongly with decreasing collision energy, and are a factor of 2 lower than thermal model predictions at this energy range. The mean p ₓ of ^3_ΛH is lower than the Blast-Wave expectation using the freeze-out parameters from light hadrons. Furthermore, the observed double ratio (^3_ΛH/Λ) / (t/p) maintains a constant value of 0. 4 across the measured energy range. Within the coalescence framework, this ratio directly reflects the significantly suppressed formation probability of the weakly-bound hypertriton relative to the triton, which results from the weaker hyperon-nucleon interaction compared with the nucleon-nucleon interaction.
the LSST Dark Energy Science Collaboration (Mon,) studied this question.