Measurements of <math><mrow><msubsup><mrow><mi>K</mi></mrow><mrow><mi>S</mi></mrow><mrow><mn>0</mn></mrow></msubsup></mrow></math>, <math><mi>Λ</mi></math>, and <math><mover><mi>Λ</mi><mo>¯</mo></mover></math> production in <math><mrow><mn>120</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi><mo>/</mo><mi>c</mi></mrow></math> <math><mrow><mi>p</mi><mo>+</mo><mi>C</mi></mrow></math> interactions

This paper presents multiplicity measurements of KS0, Λ, and Λ&#175; produced in 120 GeV/c proton-carbon interactions. The measurements were made using data collected at the NA61/SHINE experiment during two different periods. Decays of these neutral hadrons impact the measured π+, π−, p and p&#175; multiplicities in the 120 GeV/c proton-carbon reaction, which are crucial inputs for long-baseline neutrino experiment predictions of neutrino beam flux. The double-differential multiplicities presented here will be used to more precisely measure charged-hadron multiplicities in this reaction, and to reweight neutral hadron production in neutrino beam Monte Carlo simulations.