Signatures of New Physics Versus the Ridge Phenomenon in Hadron–Hadron Collisions at the LHC

Abstract

In this paper, we consider the possibility that a new stage of matter, stemming from hidden/dark sectors beyond the Standard Model, to be formed in pp collisions at the LHC, can significantly modify the correlations among final-state particles. In particular, two-particle azimuthal correlations are studied by means of a Fourier series sensitive to the near-side ridge effect while assuming that hidden/dark particles decay on top of the conventional parton shower. Then, new (fractional) harmonic terms should be included in the Fourier analysis of the azimuthal anisotropies, encoding the hypothetical new physics contribution enabling its detection in a complementary way to other signatures.

Cosmological analogies in the search for new physics in high-energy collisions

“…As already commented, this result points at very longrange correlations emerging in a "universe" under the above-mentioned evolution conditions. 2 Such an orderof-magnitude estimate is in agreement with our earlier estimates [8] about the expected long-range correlation length in azimuthal space arising from new physics. Here, we explore further the analogies between cosmic evolution and hadronic evolution under the presence of a hidden sector on top of the QCD shower.…”

“…Similarly, the study of angular correlations in highenergy collisions has traditionally been a common tool to understand multiparticle production in particle collisions beginning with early studies of cosmic rays through to current investigations at the LHC. In earlier papers, we show that one consequence of the production of a new still unknown stage of matter in high-energy hadronic collisions is to enhance long-range angular correlations among finalstate particles [6][7][8]. This conclusion bears a certain resemblance with the observed small temperature fluctuations of the CMB requiring an inflationary period right after the big bang.…”