Diphoton excess at 750 GeV in leptophobic U(1)′ model inspired by E 6 GUT

We discuss the 750 gev diphoton excess at the lhc@13tev in the framework of leptophobic u(1)′ model inspired by e 6 grand unified theory (gut). in this model, the standard model (sm) chiral fermions carry charges under extra u(1)′ gauge symmetry which is spontaneously broken by a u(1)′-charged singlet scalar (φ). in addition, extra quarks and leptons are introduced to achieve the anomaly-free conditions, which is a natural consequence of the assumed e 6 gut. these new fermions are vectorlike under the sm gauge group but chiral under new u(1)′, and their masses come entirely from the nonzero vacuum expectation value of φ through the yukawa interactions. then, the cp-even scalar h φ from φ can be produced at the lhc by the gluon fusion and decay to the diphoton via the one-loop diagram involving the extra quarks and leptons, and can be identified as the origin of diphoton excess at 750 gev. in this model, h φ can decay into a pair of dark matter particles as well as a pair of scalar bosons, thereby a few tens of the decay width be possible.