Aram Hayrapetyan, В. Макаренко, A. Tumasyan, Wolfgang Adam, L. Benato, Thomas Bergauer, M. Dragicevic, Cristina Giordano, Priya Sajid Hussain, M. Jeitler, Natascha Krammer, A. Li, Dietrich Liko, Mark Matthewman, J. Schieck, R. Schöfbeck, Maryam Shooshtari, M. Sonawane, W. Waltenberger, Claudia-Elisabeth Wulz, X. Janssen, Hyejin Kwon, Daniel Ocampo Henao, T. Van Laer, Pierre van Mechelen, Jas Bierkens, Nordin Breugelmans, J. D’Hondt, Soumya Dansana, A. De Moor, M. Delcourt, Felix Heyen, Yanwen Hong, Pavlo Kashko, Steven Lowette, I. Makarenko, D. Müller, Juhee Song, S. Tavernier, M. Tytgat, G. P. Van Onsem, S. Van Putte, D. Vannerom, Bugra Bilin, B. Clerbaux, Aloke Kumar Das, Isabelle de Bruyn, G. De Lentdecker, Hugues Evard, L. Favart, P. Gianneios, Mohammad A. Khalilzadeh, Fakhri Alam Khan, A. Malara, Muhammad Aamir Shahzad, Archana Sharma, Laurent Thomas, M. Vanden Bemden, C. Vander Velde, P. Vanlaer, Fengwangdong Zhang, M. De Coen, Didar Dobur, G. Gökbulut, David Marckx, K. Skovpen, Adina Maria Tomaru, N. Van Den Bossche, Jan van der Linden, Jules Vandenbroeck, Liam Wezenbeek, H. Aarup Petersen, Samuel Bein, A. Benecke, A. Bethani, Giacomo Bruno, A. Cappati, J. De Favereau De Jeneret, C. Delaere, Francisco Gameiro Casalinho, A. Giammanco, Ahmet Oguz Guzel, Vincent Lemaître, Jindrich Lidrych, Paul Malek, Paola Mastrapasqua, S. Turkcapar, G. A. Alves, M. Barroso Ferreira Filho, E. Coelho, C. Hensel, Diego Matos Figueiredo, T. Menezes De Oliveira, C. Mora Herrera, P. Rebello Teles, Mariana Soeiro, E. J. Tonelli Manganote, A. Vilela Pereira, W. L. Aldá Júnior, H. Brandao Malbouisson
A hot and dense state of nuclear matter, known as the quark-gluon plasma, is created in collisions of ultrarelativistic heavy nuclei. Highly energetic quarks and gluons, collectively referred to as partons, lose energy as they travel through this matter, leading to suppressed production of particles with large transverse momenta (p_{T}). Conversely, high-p_{T} particle suppression has not been seen in proton-lead collisions, raising questions regarding the minimum system size required to observe parton energy loss. Oxygen-oxygen (OO) collisions examine a region of effective system size that lies between these two extreme cases. The CMS detector at the CERN LHC has been used to quantify charged-particle production in inclusive OO collisions for the first time via measurements of the nuclear modification factor (R_{AA}). The R_{AA} is derived by comparing particle production to expectations based on proton-proton (pp) data and has a value of unity in the absence of nuclear effects. The data for OO and pp collisions at a nucleon-nucleon center-of-mass energy sqrt[s_{NN}]=5.36 TeV correspond to integrated luminosities of 6.1 nb^{-1} and 1.02 pb^{-1}, respectively. The R_{AA} is below unity with a minimum of 0.69±0.04 around p_{T}=6 GeV. The data exhibit better agreement with theoretical models incorporating parton energy loss as compared to baseline models without energy loss.