Related papers: Displaced new physics at colliders and the early u…
Weakly interacting massive particles (WIMPs) are one of very few probes of cosmology before Big Bang nucleosynthesis (BBN). We point out that in scenarios in which the Universe evolves in a non-standard manner during and after WIMP kinetic…
In contrast to the decay products ensuing from a fast moving particle which are collimated along the original direction of the parent, those from a slow moving particle are distributed over a wide region. In the context of searches for…
We study evolution and thermodynamics of a slow-roll transition between early and late time de Sitter phases, both in the homogeneous case and in the presence of a black hole, in a scalar field model with a generic potential having both a…
A search for new long-lived particles decaying to leptons is presented using proton-proton collisions produced by the LHC at sqrt(s) = 8 TeV. Data used for the analysis were collected by the CMS detector and correspond to an integrated…
Over the past decades, advancements in observational cosmology have introduced us in an era of precision cosmology, dramatically enhancing our understanding of the Universe's history as well as bringing new tensions to light. Observations…
If gravitons are super-strong interacting particles and the low-temperature graviton background exists, the basic cosmological conjecture about the Dopplerian nature of redshifts may be false: a full magnitude of cosmological redshift would…
The formation of topological defects in a second order phase transition in the early universe is an out-of-equilibrium process. Condensed matter experiments seem to support Zurek's mechanism, in which the freezing of thermal fluctuations…
We consider a broad class of supersymmetric theories in which dark matter (DM) is the lightest superpartner (LSP) of a hidden sector that couples very weakly to visible sector fields. Portal interactions connecting visible and hidden…
Current theories of particle physics lead to the unavoidable conclusion that there must have been several phase transitions in the early universe. Further, in the context of these theories, it is possible that cosmological phase transitions…
Astrophysical observations provide compelling evidence for gravitationally interacting dark matter in the universe that cannot be explained by the standard model of particle physics. The extraordinary amount of data from the CERN LHC…
A better understanding of the formation of large-scale structure in the Universe is arguably the most pressing question in cosmology. The most compelling and promising theoretical paradigm, Inflation + Cold Dark Matter, holds that the…
Millicharged particles are generic in theories of dark sectors. A cosmic or local abundance of them may be produced by the early universe, stellar environments, or the decay or annihilation of dark matter/dark energy. Furthermore, if such…
Although the existence of dark matter is well established by many astronomical measurements, its nature still remains one of the unsolved puzzles of particles physics. The unprecedented energy reached by the Large Hadron Collider (LHC) at…
We show that hidden hot dark matter, hidden-sector dark matter with interactions that decouple when it is relativistic, is a viable dark matter candidate provided it has never been in thermal equilibrium with the particles of the standard…
Recently, the CMS Collaboration has published identified particle transverse momentum spectra in high multiplicity events at LHC energies $\sqrt s $ = 0.9-13 TeV. In the present work the transverse momentum spectra have been analyzed in the…
FASER is a new LHC experiment designed to search for light, weakly-interacting particles that are produced in proton-proton collisions at the ATLAS interaction point and travel in the far-forward direction. The first physics results from…
The universe has evolved through several phases as its various constituents dominated its energy content. Candidate dark matter particles may have undergone freeze-out during any such phase. While the standard freeze-out scenarios have been…
Various theories beyond the Standard Model predict unusual signatures, including new, long-lived particles decaying at a significant distance from the collision point. These unique signatures are difficult to reconstruct and face unusual…
We propose a new strategy to look for long-lived particles (LLP) at the LHC. The LLPs are produced at one experiment, but its decay products are detected by a detector at another experiment. We use a confining Hidden Valley scenario as a…
The freeze-in mechanism provides a compelling framework for dark matter (DM) production, particularly suited to scenarios involving feeble interactions with the Standard Model (SM). In this work, we highlight a possible interplay of a…