One of the central features of the Standard Model is a field that permeates all of space and interacts with fundamental particles. The Standard Model of particle physics describes the known fundamental particles and forces that make up our Universe, with the exception of gravity. explore the way to untangle its spin origin.In 2012, physicists from the ATLAS and CMS experiments at CERN announced the discovery of a new boson looking very much like the Higgs boson. We consider for $X$ the cases of spin-1 (massless dark-photon), spin-0 (axion-like), and spin-2 (graviton-like) particles and. Due to its feeble interactions with Standard Model fields, this dark boson is behaving as missing energy in the detector.
#BOSON X DARK X BOSON PLUS#
We analyze the $Z$-boson decay $Z\to \gamma\, X$ into a photon ($\gamma$) plus a hypothetical light boson ($X$) belonging to a dark or secluded sector. The analysis is model independent, and its results can be straightforwardly applied to the search of any Higgs two-body decay into a photon plus an undetected light particle. This is considerably better than the corresponding sensitivity in alternative channels previously studied at lepton colliders. In this study, we consider eight designs of far detectors with different locations, volumes and geometries and investigate their potential for discovering long-lived axion-like particles (ALPs) via the process $e^-e^+ \rightarrow \gamma \,\, a,~ a \to \gamma\gamma $ at future $e^$ at a c.m.
#BOSON X DARK X BOSON INSTALL#
In our previous work, we have proposed to install FAr Detectors at the Electron Positron Collider (FADEPC) to enhance the discovery potential of the long-lived particles (LLPs). Perspectives for the dark photon production in Higgs-mediated processes at future e+e− colliders are also discussed. Higgs boson production and decay into a photon and a dark photon as a source of dark photons is reviewed at the Large Hadron Collider, in light of the present bounds on the corresponding signature by the CMS and ATLAS collaborations. We show how such resonant photon-plus-missing-energy signature can uniquely be connected to a dark photon production.
![boson x dark x boson boson x dark x boson](https://www.androidworld.it/wp-content/uploads/2013/12/Boson-X-Galleria-10.png)
This decay channel gives rise to a peculiar signature characterized by a monochromatic photon with energy half the Higgs mass (in the Higgs rest frame) plus missing energy. Higgs boson production at colliders, followed by the Higgs decay into a photon and a dark photon, provides then a very promising production mechanism for the dark photon discovery, being insensitive in particular regimes to the UV scale of the new physics. A violation of this expectation is provided by dark photon production mediated by the Higgs boson, thanks to the non-decoupling Higgs properties.
![boson x dark x boson boson x dark x boson](https://i3.wp.com/www.techexplorist.com/wp-content/uploads/2021/12/Higgs-boson-candidate.jpg)
Massless dark photon production at colliders will then in general be suppressed at low energy by a UV energy scale, which is of the order of the masses of portal (messenger) fields connecting the dark and the observable sectors. Contrary to the massive dark photon, a massless dark photon can only couple to the standard model sector by means of effective higher dimensional operators. Many scenarios beyond the standard model, aiming to solve long-standing cosmological and particle physics problems, suggest that dark matter might experience long-distance interactions mediated by an unbroken dark U(1) gauge symmetry, hence foreseeing the existence of a massless dark photon.