Related papers: New constraint from supernova explosions on light …
Light dark matter($\simeq 1-30~\rm{MeV}$) particles pair produced in electron-positron annihilation $ e^-e^+ \stackrel{\gamma}{\longrightarrow} \chi \bar{\chi}$ inside the supernova core can take away the energy released in the supernova…
It has been proposed that an intermediate mass black hole can produce compact molecular clouds with large velocity dispersions. This model is called into question due to the discovery of several such short lived clouds, which suggests they…
The current most stringent constraints for the existence of sub-GeV dark matter coupling to Standard Model via a massive vector boson $A^\prime$ were set by the NA64 experiment for the mass region $m_{A^\prime}\lesssim 250$ MeV, by…
Core-collapse supernovae are among Nature's grandest explosions. They are powered by the energy released in gravitational collapse and include a rich set of physical phenomena involving all fundamental forces and many branches of physics…
Sub-GeV dark matter particles can annihilate or decay producing e^\pm pairs which upscatter the low-energy photon fields in the Galaxy and generate an X-ray emission (via the Inverse Compton effect). Using X-ray data from XMM-Newton,…
The neutrino burst detected during supernova SN1987A is explained in a strangeon star model, in which it is proposed that a pulsar-like compact object is composed of strangeons (strangeon: an abbreviation of "strange nucleon"). A nascent…
As an explosion develops in the collapsed core of a massive star, neutrino emission drives convection in a hot bubble of radiation, nucleons, and pairs just outside a proto-neutron star. Shortly thereafter, neutrinos drive a wind-like…
We analyze observational constraints from TeV astrophysics on Lorentz violating nonlinear dispersion for photons and electrons without assuming any a priori equality between the photon and electron parameters. The constraints arise from…
Thermal MeV neutrino emission from core-collapse supernovae offers a unique opportunity to probe physics beyond the Standard Model in the neutrino sector. The next generation of neutrino experiments, such as DUNE and Hyper-Kamiokande, can…
Axions and other light particles appear ubiquitously in physics beyond the Standard Model, with a variety of possible couplings to ordinary matter. Cosmology offers a unique probe of these particles as they can thermalize in the hot…
Three lines of evidence indicate that in the most common type of core collapse supernovae, the energy deposited in the ejecta by the exploding core is approximately proportional to the progenitor mass cubed. This results stems from an…
Results are reported from a search for new particles that decay into a photon and two gluons, in events with jets. Novel jet substructure techniques are developed that allow photons to be identified in an environment densely populated with…
It has previously been proposed that annihilating dark matter particles with MeV-scale masses could be responsible for the flux of 511 keV photons observed from the region of the Galactic Bulge. The conventional wisdom, however, is that it…
We derive the maximum fraction of energy emitted in the form of massive (Kaluza- Klein) gravitons by core collapse supernovae, and the corresponding minimal extra-dimensional Planck mass M* in the ADD gravity framework at TeV scales. Our…
Axion-like particles (ALPs) coupled to nucleons might be copiously emitted from a supernova (SN) core. We extend existing bounds on free-streaming ALPs to the case in which these are so strongly-interacting with the nuclear matter to be…
Future galactic supernovae will provide an extremely long baseline for studying the properties and interactions of neutrinos. In this paper, we discuss the possibility of using such an event to constrain (or discover) the effects of exotic…
We estimate the rate at which collisions between ultra-high energy cosmic rays can form small black holes in models with extra dimensions. If recent conjectures about false vacuum decay catalyzed by black hole evaporation apply, the lack of…
We revisit cooling bounds on light Kaluza-Klein (KK) gravitons, as arise in the dark dimension scenario, considering red giants, neutron stars, and supernovae. In addition to bremsstrahlung, we account for two novel production channels:…
In the Randall-Sundrum model where the Standard Model fields are confined to the TeV brane located at the orbifold point $\theta = \pi$ and the gravity peaks at the Planck brane located at $\theta = 0$, the stabilized modulus (radion) field…
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…