Observation of Feynman scaling violations and evidence for a new resonance at RHIC

L. C. Bland; E. J. Brash; H. J. Crawford; A. A. Derevschikov; K. A. Drees; J. Engelage; C. Folz; E. G. Judd; X. Li; N. G. Minaev; R. N. Munroe; L. Nogach; A. Ogawa; C. Perkins; M. Planinic; A. Quintero; G. Schnell; P. V. Shanmuganathan; G. Simatovic; B. Surrow; T. G. Throwe; A. N. Vasiliev

arXiv · 1909.03124

Observation of Feynman scaling violations and evidence for a new resonance at RHIC

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Abstract

We report measurements of forward jets and dijets produced in Cu+Au collisions at $\sqrt{s_{NN}}=200$ GeV at the Relativistic Heavy Ion Collider. We also report dijet production cross sections in p+p collisions at $\sqrt{s}=510$ GeV. We use the invariant dijet mass to search for indications of new particles. The p+p dijet results are compatible with string fragmentation models tuned to fit LHC data. The Cu+Au jet results far exceed Feynman scaling limits, and are compatible with models that incorporate string fusion to increase parton energy, acting as a QCD accelerator. The Cu+Au dijet results can be mostly explained by double parton scattering due to a parton flux from multiple p+p interactions with $\sqrt{s}>>\sqrt{s_{NN}}$. Further indication of the increased parton energy is obtained from evidence of single- and double-$\Upsilon$(1S) production in the forward direction in Cu+Au collisions. Finally, we report evidence for the production of a new resonance, reconstructed from its dijet decay.

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L. C. Bland, E. J. Brash, H. J. Crawford, A. A. Derevschikov, K. A. Drees, J. Engelage, C. Folz, E. G. Judd, X. Li, N. G. Minaev, R. N. Munroe, L. Nogach, A. Ogawa, C. Perkins, M. Planinic, A. Quintero, G. Schnell, P. V. Shanmuganathan, G. Simatovic, B. Surrow, T. G. Throwe, A. N. Vasiliev. 2019-09-06. Observation of Feynman scaling violations and evidence for a new resonance at RHIC. https://arxiv.org/abs/1909.03124

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