Related papers: Constraints on Light Hidden Sector Gauge Bosons fr…
The existence of light QCD axions, whose mass depends on an additional free parameter, can lead to a new ground state of matter, where the sourced axion field reduces the nucleon effective mass. The presence of the axion field has…
We review the case for light U(1) gauge bosons in the hidden-sector of heterotic and type II string compactifications, present estimates of the size of their kinetic mixing with the visible-sector hypercharge U(1), and discuss their…
There is a growing interest for the search of new light gauge bosons. The small mass of a new boson can turn various kinds of low-energy experiments to a new discovery machine, depending on their couplings to the standard model particles.…
We consider a hidden sector model of dark matter which is charged under a hidden U(1)_X gauge symmetry. Kinetic mixing of U(1)_X with the Standard Model hypercharge U(1)_Y is allowed to provide communication between the hidden sector and…
We study supernova cooling constraints on new light scalars that mix with the Higgs, couple only to nucleons, or couple only to leptons. We show that in all these cases scalars with masses smaller than the plasma frequency in the supernova…
If large extra dimensions exist in nature, supernova (SN) cores will emit large fluxes of Kaluza-Klein gravitons, producing a cosmic background of these particles with energies and masses up to about 100 MeV. Radiative decays then give rise…
During the accretion phase of a core-collapse supernova (SN), dark-photon (DP) cooling can be largest in the gain layer below the stalled shock wave. In this way, it could counter-act the usual shock rejuvenation by neutrino energy…
We derive supernova (SN) bounds on muon-philic bosons, taking advantage of the recent emergence of muonic SN models. Our main innovations are to consider scalars $\phi$ in addition to pseudoscalars $a$ and to include systematically the…
An alternative mechanism that dims high redshift supernovae without cosmic acceleration utilizes an oscillation of photons into a pseudo-scalar particle during transit. Since angular diameter distance measures are immune to the loss of…
High-energy particle physics experiments allow for the possible existence of a new light, very weakly coupled, neutral gauge boson (the U boson). This one permits for light (spin-1/2 or spin-0) particles to be acceptable Dark Matter…
We summarize current constraints on the couplings of the Higgs boson in the framework of an effective theory beyond the Standard Model.
Dark photons, a generic class of light gauge bosons that interact with the Standard Model (SM) exclusively through kinetic mixing, arise naturally in many gauge extensions of the SM. Motivated by these theoretical considerations, we present…
It has been suggested that a potentially large fraction of supernovae could be accompanied by relativistic outflows that stall below the stellar surface. In this letter we point out that internal shocks that are believed to accelerate…
Recent analysis of the Milky Way's satellite galaxies reveals that these objects share a common central mass density, even though their luminosities range over five orders of magnitude. This observation can be understood in the context of…
Dark photons, hypothetical feebly interacting massive vector bosons, appear in many extensions of the Standard Model. This study investigates their production and subsequent decay during supernova explosions. We demonstrate that the decay…
We consider experimental constraints in the MeV region in order to determine the parameter space for the $U(1)_X$ extension of the Standard Model, presented in the first part of our work. In particular, we focus on the model UV-completed by…
We study a scenario that a hidden gauge boson constitutes the dominant component of dark matter and decays into the standard model particles through a gauge kinetic mixing. Interestingly, gamma rays and positrons produced from the decay of…
The phenomenological constraints on extra neutral gauge bosons at present and at future colliders are reviewed. Special attention is paid to the influence of radiative corrections, systematic errors, and kinematic cuts on the Z'…
If annihilating MeV-scale dark matter particles are responsible for the observed 511 keV emission from the Galactic bulge, then new light gauge bosons which mediate the dark matter annihilations may have other observable consequences. In…
The nature of dark matter is one of the most thrilling riddles for both cosmology and particle physics nowadays. While in the typical models the dark sector is composed only by weakly interacting massive particles, an arguably more natural…