The 750 GeV LHC diphoton excess from a baryon number conserving string model

TL;DR

This paper explains the 750 GeV diphoton excess at the LHC using a string theory model with gauged baryon number, identifying the resonance as either a sneutrino or an axion, and explores the implications for string scale and particle couplings.

Contribution

It introduces a string-inspired model that accounts for the 750 GeV resonance, linking it to supersymmetry and specific particle interactions, which is a novel approach.

Findings

String scale constrained between 10^14 and 10^19 GeV.

Sneutrino produced via gluon fusion with supersymmetric partners.

Axion coupling to gauge bosons naturally suppressed.

Abstract

We propose an explanation of the LHC data excess resonance of 750 GeV in the diphoton distribution using D-brane models, with gauged baryon number, which accommodate the Standard Model together with vector like exotics. We identify the 750 GeV scalar as either the sneutrino (${\tilde \nu}_R$) or as an axion. Using a bottom-up approch, ${\tilde \nu}_R$ is produced via gluon fusion when scalar (supersymmetric) partners of vector like quarks and leptons are generated by demanding that the corresponding intersections respect N=1 supersymmetry. When we generate the value of ${\tilde \nu}_R$ at 750 GeV, by varying the complex structure of the torus, the string scale is limited to be in the range $ 10^{14} < M_s < 10^{19}$ GeV. Also, generating the Higgs scalars by imposing N=1 supersymmetry on intersections fixes naturally, to zero, the coupling of the axion to SU(2) gauge bosons $\propto F_b \wedge F_b$ and in photon-photon fusion also decouples its coupling from $G^2$ of color SU(3) by simultaneously generating the superpartners of $q_L$, $U_R$, $l_L$, $\nu_R$ quarks and leptons.