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Related papers: Features in the Standard Model diphoton background

200 papers

We propose that the diphoton excess at 750 GeV reported by ATLAS and CMS is due to the decay of an ${\it exo-Higgs}$ scalar $\eta$ associated with the breaking of a new $SU(2)_e$ symmetry, dubbed ${\it exo-spin}$. New fermions, ${\it…

High Energy Physics - Phenomenology · Physics 2016-07-15 Hooman Davoudiasl , Pier Paolo Giardino , Cen Zhang

The rare decays $\eta^{(\prime)}\to\ell^+\ell^-$, $\ell\in\{e,\mu\}$, are highly suppressed in the Standard Model, both by their chirality structure and the required loop attaching the lepton line to the $\eta^{(\prime)}\to\gamma^*\gamma^*$…

High Energy Physics - Phenomenology · Physics 2026-04-13 Noah Messerli , Martin Hoferichter , Bai-Long Hoid , Simon Holz , Bastian Kubis

The neutral component of a real pseudoscalar electroweak (EW) triplet can produce a diphoton excess at 750 GeV, if it is somewhat mixed with an EW singlet pseudoscalar. This triplet-singlet mixing allows for greater freedom in the diboson…

High Energy Physics - Phenomenology · Physics 2016-08-31 Kiel Howe , Simon Knapen , Dean J. Robinson

Certain modified gravity theories predict the existence of an additional, non-conformally coupled scalar field. A disformal coupling of the field to the Cosmic Microwave Background (CMB) is shown to affect the evolution of the energy…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Carsten van de Bruck , Jack Morrice , Susan Vu

A comparison of the inclusive photon energy spectrum in the radiative decay $\BGAMAXS$, measured recently by the CLEO collaboration, with the standard model is presented, using a $B$-meson wave function model and improving earlier…

High Energy Physics - Phenomenology · Physics 2011-01-05 A. Ali , C. Greub

We discuss the 750 GeV diphoton excess at the LHC@13TeV in the framework of leptophobic U(1)$^\prime$ model inspired by $E_6$ grand unified theory (GUT). In this model, the Standard Model (SM) chiral fermions carry charges under extra…

High Energy Physics - Phenomenology · Physics 2016-04-21 P. Ko , Yuji Omura , Chaehyun Yu

The excess of events in the diphoton final state near 750 GeV observed by ATLAS and CMS can be explained within the NMSSM near the R-symmetry limit. Both scalars beyond the Standard Model Higgs boson have masses near 750 GeV, mix strongly,…

High Energy Physics - Phenomenology · Physics 2016-05-18 Ulrich Ellwanger , Cyril Hugonie

We propose that the diphoton resonance signal indicated by the recent LHC data might also arise from the pair productions of vector-like heavy down-type quarks with mass around $750$ GeV and above. The vector-like quark decays into an…

High Energy Physics - Phenomenology · Physics 2016-07-05 Kasinath Das , Tianjun Li , S. Nandi , Santosh Kumar Rai

The in-medium properties of $\eta$ mesons are studied in hot and dense isospin asymmetric strange magnetized matter using the chiral SU(3) hadronic mean-field model. The scalar and vector density of baryons are expressed in terms of thermal…

High Energy Physics - Phenomenology · Physics 2022-11-22 Shivanshi Tiwari , Rajesh Kumar , Manisha Kumari , Arvind Kumar

Analytic expressions of lepton-flavour- and lepton-number-violating decays of charged leptons are derived in the context of general $SU(2)_L\otimes U(1)_Y$ seesaw scenarios that are motivated by grand unified theories (GUT's) or superstring…

High Energy Physics - Phenomenology · Physics 2009-10-28 A. Ilakovac , A. Pilaftsis

Motivated by the diphoton excess at 750 GeV reported by the ATLAS and CMS experiments, we present an F-theory inspired flipped $SO(10)$ model embedded in an $E_6$ GUT. The low energy spectrum includes the three MSSM chiral families,…

High Energy Physics - Phenomenology · Physics 2016-11-23 George K. Leontaris , Qaisar Shafi

In the context of a nonuniversal and anomaly free $U(1)_{X}$ extension of the standard model, we examine the decay of a $750$GeV scalar singlet state, $\xi_{\chi}$, as a possible explanation of the observed diphoton excess announced by the…

High Energy Physics - Phenomenology · Physics 2016-10-12 R. Martinez , F. Ochoa , C. F. Sierra

We study the 2010 specific version of the 2002 proposed $U(1)_X$ extension of the supersymmetric standard model, which has no $\mu$ term and conserves baryon number and lepton number separately and automatically. We consider in detail the…

High Energy Physics - Phenomenology · Physics 2016-06-29 Sean Fraser , Corey Kownacki , Ernest Ma , Nicholas Pollard , Oleg Popov , Mohammadreza Zakeri

ATLAS and CMS have each reported a modest diphoton excess consistent with the decay of a broad resonance at ~ 750 GeV. We show how this signal can arise in a weakly coupled theory comprised solely of narrow width particles. In particular,…

High Energy Physics - Phenomenology · Physics 2015-12-29 Haipeng An , Clifford Cheung , Yue Zhang

Nowadays the field of searching for a new physics became a very interesting subject in a light meson decays due to a recent results from KTeV collaboration which found the 3.3\sigma\ disagreement between Standard Model theory and their…

Nuclear Experiment · Physics 2013-01-28 Marcin Berlowski

The recently observed diphoton anomaly at the LHC appears to suggest the presence of a rather broad resonance. In this note, it is pointed out that this does not hold if the two photons are produced along with an extra state. Specifically,…

High Energy Physics - Phenomenology · Physics 2016-05-04 Jérémy Bernon , Christopher Smith

We explore several perturbative scenarios in which the di-photon excess at 750 GeV can potentially be explained: a scalar singlet, a two Higgs doublet model (2HDM), a 2HDM with an extra singlet, and the decays of heavier resonances, both…

High Energy Physics - Phenomenology · Physics 2016-06-01 Wolfgang Altmannshofer , Jamison Galloway , Stefania Gori , Alexander L. Kagan , Adam Martin , Jure Zupan

We construct the electromagnetic anomaly effective term for a generalized linear sigma model with two chiral nonets, one with a quark-antiquark structure, the other one with a four quark content. We compute in the leading order of this…

High Energy Physics - Phenomenology · Physics 2017-06-07 Amir H. Fariborz , Renata Jora

We show that the 750 GeV diphoton excess can be explained by introducing vector-like quarks and hidden fermions charged under a hidden U(1) gauge symmetry, which has a relatively large coupling constant as well as a significant kinetic…

High Energy Physics - Phenomenology · Physics 2016-08-24 Fuminobu Takahashi , Masaki Yamada , Norimi Yokozaki

We present the magnetic dipole($M1$) transitions $V\to P\gamma$ of various heavy-flavored mesons such as $(D,D^*,D_s,D^{*}_s,\eta_c, J/\psi)$ and $(B,B^*,B_s,B^*_s,\eta_b,\Upsilon)$ using the light-front quark model constrained by the…

High Energy Physics - Phenomenology · Physics 2011-08-31 Ho-Meoyng Choi