Search for narrow resonances in dijet final states at sqrt(s) = 8 TeV with the novel CMS technique of data scouting

TL;DR

This paper reports a search for narrow dijet resonances at 8 TeV using CMS data collected with a novel data scouting technique, significantly enhancing sensitivity to low-mass resonances and setting new limits on possible new particles.

Contribution

The study introduces a data scouting method in CMS that allows for larger data collection, improving sensitivity to low-mass dijet resonances compared to previous approaches.

Findings

No evidence of narrow resonances was found.

Upper limits on resonance cross sections were established.

Constraints on the coupling of hypothetical Z' bosons were improved.

Abstract

A search for narrow resonances decaying into dijet final states is performed on data from proton-proton collisions at a center-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 18.8 inverse femtobarns. The data were collected with the CMS detector using a novel technique called data scouting, in which the information associated with these selected events is much reduced, permitting collection of larger data samples. This technique enables CMS to record events containing jets at a rate of 1 kHz, by collecting the data from the high-level-trigger system. In this way, the sensitivity to low-mass resonances is increased significantly, allowing previously inaccessible couplings of new resonances to quarks and gluons to be probed. The resulting dijet mass distribution yields no evidence of narrow resonances. Upper limits are presented on the resonance cross sections as a function of mass, and compared with a variety of models predicting narrow resonances. The limits are translated into upper limits on the coupling of a leptophobic resonance Z'[B] to quarks, improving on the results obtained by previous experiments for the mass range from 500 to 800 GeV.