English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We explore the possibility of a beyond the standard model scalar ($\phi$) asa possible explanation of the diphoton resonance at 750~GeV invariant massreported by the ATLAS and CMS collaborations at the large hadron collider(LHC). We first present in a model-independent way the scalar-gluon-gluon andscalar-photon-photon effective couplings needed for obtaining the requireddiphoton cross-section at the LHC for different total widths. We investigatehere two new-physics possibilities that can generate these effective couplings,namely, (i) the 2-Higgs-doublet model (2HDM) in the alignment limit, and (ii) asinglet scalar, with vector-like fermions added and playing a crucial role ingenerating the effective couplings. We present the regions of model parameterspace which are allowed by direct LHC and perturbative unitarity constraints,and that give the required diphoton cross-section at the LHC for various totalwidths. In the singlet case, we include the possibility that $\phi$ decays intoa pair of neutral stable vector-like fermions that could be dark matter. Wefind regions of parameter-space of the singlet model that gives the requireddiphoton rate, have the correct dark matter relic-density, have dark matterdirect-detection rates compatible with current direct-detection experiments,and satisfy LHC bounds and perturbative unitarity constraints.

The 750 GeV diphoton excess in a two Higgs doublet model and a singlet  scalar model, with vector-like fermions, unitarity constraints, and dark  matter implications