The ATLAS and CMS Collaborations of the Large Hadron Collider (LHC) have reported an excess of events in diphoton channel with invariant mass of about 750 GeV. With low energy supersymmetry breaking, we systematically consider the sgoldstino scalar S as the new resonance, which is a linear combination of the CP-even scalar s and CP-odd pseudoscalar a. Because we show that s and a can be degenerated or have large mass splitting, we consider two cases for all the following three scenarios: (1) Single resonance. s is the 750 GeV resonance decays to a pair of 1 GeV pseudoscalar a. With suitable decay length, these two a decay into collimated pair of photons which cannot be distinguished at the LHC and may appear as diphotons instead of four photons. (2) Twin resonances. m s ≈ m a with a mass difference of about 40 GeV and both s and a decay into diphoton pairs. For productions, we consider three scenarios: (I) vector boson fusion; (II) gluon gluon fusion; (III) qq pair production. In all these scenarios with two kinds of resonances, we find the parameter space that satisfies the diphoton production cross section from 3 to 13 fb and all the other experimental constraints. And we address the decay width as well. In particular, in the third scenario, we observe that the production cross section is small but the decay width of s or a can be from 40 to 60 GeV.

Recently, an excess of events in diphoton channel with invariant mass of about 750 GeV has been reported by the ATLAS and CMS Collaborations. Considering it as a tantalizing hint for new physics beyond the Standard Model (SM), we propose a simple extension of the SM with an additional doublet Higgs H and a singlet s. We consider the neutral component H 0 of H as the 750 GeV resonance, and assume that s is lighter than 2.6 GeV. In particular, H 0 can be produced at tree level via qq production, and decay into a pair of s at tree level. And then s can decay into a pair of collimated photons, which cannot be distinguished at the LHC. We show that the diphoton production cross section can be from 3 to 13 fb, the decay width of H 0 can be from 30 to 60 GeV, and all the current experimental constraints including dijet constraint can be satisfied.