Related papers: From diffuse extragalactic and galactic gamma rays…
We discuss phenomenology of extra time dimensions in a scenario where the standard model particles are localized in ``our'' time, whereas gravity can propagate in all time dimensions. For an odd number of extra times, at small distances,…
Very high energy (VHE, energy $E \gtrsim 100$\,GeV) \gamma-rays from cosmological sources are attenuated due to the interaction with photons of the extragalactic background light (EBL) in the ultraviolet to infrared wavelength band. The…
We present a study of $\gamma$-ray emission from the core-collapse supernova remnant Cas~A in the energy range from 0.1GeV to 10TeV. We used 65 hours of VERITAS data to cover 200 GeV - 10 TeV, and 10.8 years of \textit{Fermi}-LAT data to…
We report a search for large extra spatial dimensions in $p\bar{p}$ collisions at a center of mass energy of 1.8 TeV at the Tevatron. We present recent D0 results on graviton-mediated exchange processes, using events containing a pair of…
The aim of this talk is to provide non-experts with a brief and elementary introduction on the field of extra dimensions. The main motivation for extra dimensions relies on the more fundamental string theories that predict ten (or eleven)…
Beginning from the standard Arnowitt-Deser-Misner (ADM) formulation of general relativity we construct a tentative model of quantum gravity from the point of view of an observer with constant proper acceleration, just outside of a horizon…
The public data from the EGRET space telescope on diffuse galactic gamma rays in the energy range from 0.1 to 10 GeV show an excess for energies above 1 GeV in comparison with the expectations from conventional galactic models. This excess…
We consider the production of gravitons via two photon and electron-photon fusion in Kaluza-Klein theories which allow TeV scale gravitational interactions. We show that at electron-positron colliders, the processes l+l- -> l+ l- graviton,…
We consider the general expressions for the time delay of photons of different energies in the framework of multi-dimensional cosmological models. In models with compactified extra-dimensions (Kaluza-Klein type models), the main source of…
Cosmic rays of energies up to a few PeV are believed to be of galactic origin, yet individual sources have still not been firmly identified. Due to inelastic collisions with the interstellar gas, cosmic-ray nuclei produce a diffuse flux of…
It has been known for some time that warped extra dimensions offer a potential explanation of the large hierarchy that exists between the electroweak scale and the Planck scale. The majority of this work has focused on a five dimensional…
We explore in detail a dilatonic scalar-tensor theory of gravity inspired by large extra dimensions, where a radion field from compact extra dimensions gives rise to quintessence in our 4-dimensional world. We show that the model can give…
The Extragalactic Background Light (EBL) includes photons with wavelengths from ultraviolet to infrared, which are effective at attenuating gamma rays with energy above ~10 GeV during propagation from sources at cosmological distances. This…
We discuss the problem of the absorption of very high-energy gamma-rays by pair production interactions with extragalactic photons which originate from stellar emission in the near IR-UV and reradiation of starlight in the mid- and far-IR.…
A procedure to derive bounds on coupling strengths of exotic particles to nucleons from the neutrino signal of supernovae is outlined. The analysis is based on a model independent calculation for the emissivities for the exotic, detailed…
In the presence of large extra dimensions, the fundamental Planck scale can be much lower than the apparent four-dimensional Planck scale. In this setup, the weak gravity conjecture implies a much more stringent constraint on the UV cutoff…
We present a two-parameter model of the extragalactic gamma-ray background (EGB) in the 0.1-100 GeV range as measured by the Large Area Telescope (LAT) onboard the Fermi satellite. The EGB can be fully explained as the sum of three distinct…
Many efforts have been devoted to the studies of the phenomenology in particle physics with extra dimensions. We propose degenerate fermion stars with extra dimensions and study what features characterized by the size of extra dimensions…
The introduction of extra space dimensions in the theory could be an elegant way tovsolve the hierarchy problem. There could even be one energy scale at which all interactions could unify. The limits coming from our knowledge of the…
Measuring the diffuse Galactic gamma-ray flux in the TeV range is difficult for ground-based gamma-ray telescopes because of the residual cosmic-ray background, which is higher than the gamma-ray flux by several orders of magnitude. Its…