Measurements of $$\pi ^\pm $$, $$K^\pm $$, p and $$\bar{p}$$ spectra in $$^{40}\hbox {Ar+}^{45}\hbox {Sc}$$ collisions at 13A to 150A $$\text{ Ge }\hspace{-1.00006pt}\text{ V }\!/\!c$$
H. Adhikary, P. Adrich, K. K. Allison, N. Amin, Evgeny Andronov, T. Antičić, I. C. Arsene, M. Bajda, Y. Balkova, M. Baszczyk, D. Battaglia, A. Bazgir, S. Bhosale, M. Bielewicz, A. Blondel, M. Bogomilov, Y. Bondar, N. Bostan, A. V. Brandin, W. Bryliński, J. Brzychczyk, M. Buryakov, A. F. Camino, M. Ćirković, M. Csanád, J. Cybowska, T. Czopowicz, C. Dalmazzone, N. Davis, A. Dmitriev, P. von Doetinchem, W. Dominik, P. Dorosz, J. Dumarchez, R. Engel, Г. Феофилов, L. Fields, Z. Fodor, M. Friend, M. Gaździcki, O. Golosov, V.M. Golovatyuk, M. Golubeva, K. Grebieszkow, F. Guber, S. N. Igolkin, S. Ilieva, A. Ivashkin, A. Izvestnyy, K. Kadija, Н. И. Каргин, N. Karpushkin, E. Kashirin, M. M. Kielbowicz, V. A. Kireyeu, Hiroshi Kitagawa, R. Kolesnikov, D. Kolev, Y. Koshio, V. Kovalenko, S. Kowalski, B. Kozłowski, A. Krasnoperov, W. Kucewicz, M. Kuchowicz, M. Kuich, A. Kurepin, Á. László, M. P. Lewicki, G. I. Lykasov, V. Lyubushkin, M. Maćkowiak-Pawłowska, Z. Majka, A. Makhnev, B. Maksiak, A. Malakhov, A. Marcinek, A. D. Marino, H.-J. Mathes, T. Matulewicz, V. Matveev, G. L. Melkumov, A. Merzlaya, Ł. Mik, A. Morawiec, S. Morozov, Y. Nagai, T. Nakadaira, M. Naskręt, S. Nishimori, V. Ozvenchuk, O. Panova, V. Paolone, O. Petukhov, I. Pidhurskyi, R. Płaneta, P. Podlaski, B. Popov, B. Pórfy, M. Posiadała-Zezula
Abstract
Abstract The NA61/SHINE experiment at the CERN Super Proton Synchrotron studies the onset of deconfinement in strongly interacting matter through a beam energy scan of particle production in collisions of nuclei of varied sizes. This paper presents results on inclusive double-differential spectra, transverse momentum and rapidity distributions and mean multiplicities of $$\pi ^\pm $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mi>π</mml:mi> <mml:mo>±</mml:mo> </mml:msup> </mml:math> , $$K^\pm $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mi>K</mml:mi> <mml:mo>±</mml:mo> </mml:msup> </mml:math> , p and $$\bar{p}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mover> <mml:mrow> <mml:mi>p</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>¯</mml:mo> </mml:mrow> </mml:mover> </mml:math> produced in $$^{40}\hbox {Ar+}^{45}\hbox {Sc}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msup> <mml:mrow/> <mml:mn>40</mml:mn> </mml:msup> <mml:msup> <mml:mtext>Ar+</mml:mtext> <mml:mn>45</mml:mn> </mml:msup> <mml:mtext>Sc</mml:mtext> </mml:mrow> </mml:math> collisions at beam momenta of 13 A , 19 A , 30 A , 40 A , 75 A and 150 A $$\text{ Ge }\hspace{-1.00006pt}\text{ V }\!/\!c$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mspace/> <mml:mtext>Ge</mml:mtext> <mml:mspace/> <mml:mspace/> <mml:mspace/> <mml:mtext>V</mml:mtext> <mml:mspace/> <mml:mspace/> <mml:mo>/</mml:mo> <mml:mspace/> <mml:mi>c</mml:mi> </mml:mrow> </mml:math> . The analysis uses the 10% most central collisions, where the observed forward energy defines centrality. The energy dependence of the $$K^\pm $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mi>K</mml:mi> <mml:mo>±</mml:mo> </mml:msup> </mml:math> / $$\pi ^\pm $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mi>π</mml:mi> <mml:mo>±</mml:mo> </mml:msup> </mml:math> ratios as well as of inverse slope parameters of the $$K^\pm $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mi>K</mml:mi> <mml:mo>±</mml:mo> </mml:msup> </mml:math> transverse mass distributions are placed in between those found in inelastic $$p+p$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mi>p</mml:mi> <mml:mo>+</mml:mo> <mml:mi>p</mml:mi> </mml:mrow> </mml:math> and central Pb + Pb collisions. The results obtained here establish a system-size dependence of hadron production properties that so far cannot be explained either within statistical or dynamical models.