Related papers: Bounds on large extra dimensions from photon fusio…
Recent work has shown that dispersion relations with Planck scale Lorentz violation can produce observable effects at energies many orders of magnitude below the Planck energy M. This opens a window on physics that may reveal quantum…
We reanalyse the limits on the gravitino mass $m_{3/2}$ in superlight gravitino scenarios derived from arguments on energy-loss during gravitational collapse. We conclude that the mass range $10^{-6}eV\leq m_{3/2}\leq2.3\times10^{-5}eV$ is…
If axions or other low-mass pseudoscalars couple to electrons (``fine structure constant'' $\alpha_a$) they are emitted from red giant stars by the Compton process $\gamma+e\to e+a$ and by bremsstrahlung $e+(Z,A)\to (Z,A)+e+a$. We construct…
Unequal strengths of boundary localised terms lead to non-conservation of the Kaluza-Klein (KK) parity in the 4 + 1 Universal Extra Dimensional model. Consequently the first excited KK-partners of Standard Model particles are not stable by…
We calculate limits on the properties of neutrinos using data from gamma-ray detectors on the Pioneer Venus Orbiter and Solar Max Mission satellites. A massive neutrino decaying in flight from the supernova would produce gamma rays…
Experimental limits on the violation of four-dimensional Lorentz invariance imply that noncommutativity among ordinary spacetime dimensions must be small. Noncommutativity among extra, compactified spatial dimensions, however, is far less…
The prospect of experimental verification of the large extra dimension scenario in rare decays is discussed. The case of J/\Psi and \Upsilon to photon + missing energy is calculated in detail, and it is shown that the limit on the…
A search for large extra spatial dimensions via virtual-graviton exchange in the diphoton channel has been carried out with the CMS detector at the LHC. No excess of events above the standard model expectations is found using a data sample…
In universal extra-dimensional models a conserved Z_2 parity stabilizes the lightest Kaluza-Klein particle, a dark-matter candidate. Boundary-localized kinetic terms, in general, do not preserve this symmetry. We examine, in the presence of…
In this paper, we perform a comprehensive study to probe the effects of large extra dimensions through double Higgs production in proton-proton collisions at the center-of-mass energies of 14, 33, 100 TeV. We concentrate on the channel in…
There are several advantages of introducing adjoint superfields at intermediate energies around $M=10^{13}$ GeV. Such as (i) gauge couplings still unify (ii) neutrino masses and mixings are produced (iii) primordial lepton asymmetry can be…
The cumulative emission of Axion-Like Particles (ALPs) from all past core-collapse supernovae (SNe) would lead to a diffuse flux with energies ${\mathcal O}(50)$ MeV. We use this to constrain ALPs featuring couplings to photons and to…
We discuss limits on neutrino-Majoron couplings both from laboratory experiments as well as from astrophysics. They apply to the simplest class of Majoron models which covers a variety of possibilities where neutrinos acquire mass either…
We compute the contribution of Kaluza-Klein graviton exchange to the cross section for photon-neutrino scattering. Unlike the usual situation where the virtual graviton exchange represents a small correction to a leading order electroweak…
A search for a new heavy scalar resonance decaying to two Z bosons, each subsequently decaying to a pair of electrons or muons, is presented. The results are based on a proton-proton collision data set collected by the CMS experiment at the…
We argue that extensions of the Standard Model (SM) with a warped extra dimension, which successfully address the hierarchy and flavor problems of elementary particle physics, can provide an elegant explanation of the 750 GeV diphoton…
We discuss collider signatures of (1,1)-th Kaluza-Klein (KK) mode vector bosons in the framework of two universal extra dimension model, at a future electron-positron collider. Production of the (1,1)-th KK mode of electro-weak vector…
Universal extra dimensions, presumably observable at some high-energy scale, would modify low-energy observables, being particularly relevant for physical processes forbidden at tree level by the Standard Model. We address the Kaluza-Klein…
We report on recent constraints on models with a flat ``universal'' extra dimension in which all Standard Model fields propagate in the bulk. A significantly improved constraint on the compactification scale is obtained from the extended…
We study constraints on models with a flat "Universal'' Extra Dimension in which all Standard Model fields propagate in the bulk. A significantly improved constraint on the compactification scale is obtained from the extended set of…