35 research outputs found
Right handed neutrinos, TeV scale BSM neutral Higgs boson, and FIMP dark matter in an EFT framework
No full textInternational audienceWe consider an effective field theory framework with three Standard Model (SM) gauge singlet right-handed neutrinos, and an additional SM gauge singlet scalar field. The framework successfully generates eV masses of light neutrinos via the seesaw mechanism, and accommodates a feebly interacting massive particle (FIMP) as a dark matter candidate. Two of the gauge singlet neutrinos participate in neutrino mass generation, while the third gauge singlet neutrino is a FIMP dark matter. We explore the correlation between the vev (vacuum expectation value) of the gauge singlet scalar field which translates as mass of the BSM Higgs, and the mass of dark matter, which arises due to the relic density constraint. We furthermore explore the constraints from the light neutrino masses in this setup. We chose the gauge singlet BSM Higgs in this framework in the TeV scale. We perform a detailed collider analysis to explore the discovery prospect of the TeV scale BSM Higgs through its difatjet signature, at a future pp collider which can operate with s=100 TeV c.m. energy
Dark matter to baryon ratio from scalar triplets decay in type-II seesaw
No full textWe propose a minimal model for the cosmic coincidence problem and neutrino mass in a type-II seesaw scenario. We extend the standard model of particle physics with a singlet leptonic Dirac fermion , which represents the candidate of dark matter (DM), and two triplet scalars with hierarchical masses. In the early Universe, the CP violating out-of-equilibrium decay of lightest generates a net asymmetry in the visible sector (comprising of SM fields), where B and L represents the total baryon and lepton number respectively. A part of this asymmetry gets transferred to the dark sector (comprising of DM ) through a dimension eight operator which conserves . Above the electroweak phase transition, the asymmetry of the visible sector gets converted to a net B-asymmetry by the violating sphalerons, while the asymmetry of the dark sector remains untouched which we see today as relics of DM. We show that the observed DM abundance can be explained for a DM mass about 8 GeV. We then introduce an additional singlet scalar field which mixes with the SM-Higgs to annihilate the symmetric component of the DM resonantly which requires the singlet scalar mass to be twice the DM mass, i.e. around 16 GeV, which can be searched at collider experiments. In our model, the active neutrinos also get small masses by the induced vacuum expectation value (vev) of the triplet scalars . In the later part of the paper we discuss all the constraints on model parameters coming from invisible Higgs decay, Higgs signal strength, DM direct detection and relic density of DM
Dark Sector extensions of the Littlest Seesaw in the presence of Primordial Black Holes
No full textThe Littlest Seesaw model is a very well motivated dark matter model. Here we
consider an extension of that model with an additional scalar and an additional
fermionic particle under the freeze-in scenario. Formation of black hole of a
certain mass range at primordial times can act as an alternate production
mechanism for the dark matter particles as it evaporates via Hawking radiation.
Furthermore, the presence of primordial black holes with substantial energy
density gives rise to non-standard cosmology which also modifies the freeze-in
production. In this paper, we have investigated the extended Littlest Seesaw
model under the freeze-in scenario in the presence of a primordial black hole
for various interesting cases and constrained the parameter space accordingly.
If the universe is primordial black hole dominated at any point in the
evolution of the universe, we find that the final relic in that case is
dominated mostly by the evaporation component for a high dark matter mass and
by the freeze-in component for a low dark matter mass.Comment: 14 pages, 8 figures, accepted in JCA
Dark Matter Phenomenology in an Extended Littlest Seesaw Model and Effects of Primordial Black Hole
No full textWe consider an extension of the Littlest Seesaw model with an additional scalar and a fermionic particle under the freeze-in scenario. Primordial black holes of a certain mass range can act as an alternate production mechanism for the dark matter particles as it evaporates via Hawking radiation. Furthermore, the presence of primordial black holes with substantial energy density give rise to non-standard cosmology which also modifies the freeze-in production. We have investigated this freeze-in scenario in presence of primordial black holes for a few interesting cases and constrained the parameter space accordingly. If the universe is primordial black hole dominated at any point before Big Bang Nucleosynthesis, we have found that the final relic in that case is constituted mostly by the evaporation component in the high dark matter mass and by the freeze-in component in the low dark matter mass
Dark matter phenomenology in an extended littlest seesaw model and effects of primordial black hole
No full textWe consider an extension of the Littlest Seesaw model with an additional scalar and a fermionic particle under the freeze-in scenario. Primordial black holes of a certain mass range can act as an alternate production mechanism for the dark matter particles as it evaporates via Hawking radiation. Furthermore, the presence of primordial black holes with substantial energy density give rise to non-standard cosmology which also modifies the freeze-in production. We have investigated this freeze-in scenario in presence of primordial black holes for a few interesting cases and constrained the parameter space accordingly. If the universe is primordial black hole dominated at any point before Big Bang Nucleosynthesis, we have found that the final relic in that case is constituted mostly by the evaporation component in the high dark matter mass and by the freeze-in component in the low dark matter mass
Testing electroweak scale seesaw models at and colliders
No full textWe investigate the possibilities of probing the electroweak scale seesaw
scenarios such as type-I, type-II and type-III seesaw at and
colliders. For the case of type-I seesaw, the heavy neutrinos
can be produced at colliders in association with a boson. We
study a variety of final states in this case including single and multilepton
modes in association with jets to estimate bounds on the light-heavy neutrino
mixing angle. In case of type-II seesaw, doubly charged multiplets of the
SU triplet scalar can be produced in pair at collider.
We study the multi-leptonic decay modes coming from this pair production of
doubly charged Higgs and show how one can probe neutrino mass hierarchy. We
also study same sign boson production from the doubly charged Higgs to
study multilepton modes in association with missing energy. From the type-III
seesaw, we study same sign dilepton+jets and trilepton+jets modes at
collider which are coming from the neutral and charged component of
the triplet fermion in association with a boson and boson,
respectively. Due to the existing limits on the triplet fermions from the LHC
we choose heavier mass so that the gauge boson originated from the decay of a
neutral multiplet can be sufficiently boosted producing a fat-jet signature in
association with same sign dilepton and trilepton. Finally we estimate bounds
on the light neutrino-heavy triplet fermion mixing angle and compare with the
existing bounds.Comment: 53 pages, 30 figure
이상의 「종생기」에 나타난 사랑, 죽음, 예술
No full textThis essay aims at overcoming the two main interpretations of Yi Sangs ecriture. One is the biographical interpretation which reduces Yi Sangs literature into the documents of his despair and fear and the other is the semiological interpretation which makes his texts a hollow art isolated from life or an abstract play of signs. However, inscription of proper name(Yi Sang) in his texts is not any reference to the author"s presumed identity but a kind of strategy for disrupting Is unified identity and dissolving epistemological representationalism and literary realism. Yi Sangs texts play variations on the theme of nonidentical identity by motives of the mirror, the mask, the double and broken bodies, all of which also disturb the layers of narration. The criticism of representationalism leads to the cognitive way of sign-decoding and the layer of narrative of Yi Sangs texts can, thus, be summarized in some struggles for decoding the violent signs(Oedipus family, modernity and fascism, love, death) which are emitted from the obscure world. Especially, Writing on Death is a peak of Yi Sang"s literature because it envelops love and death in art. His viewpoint of art, condensed into the allusion of Soneynhaeng(少年行), implicates a paradox that one can"t reach art not by wasting his/her life and, in turn, the essence of life which he/she can glimpse only in art, is already dissipated in life itself. Moreover, Yi Sang has made persistent efforts to affirm both life and death by striking pose for suicide and accomplishes amor fati through art(Writing on Death) which overcomes Death and comes repeatedly across life, the world, and the Real
Automated predictions from polarized matrix elements
No full textThe anticipated experimental resolution and data cache of the High Luminosity Large Hadron Collider will enable precision investigations of polarization in multiboson processes. This includes, for the first time, vector boson scattering. To facilitate such studies, we report the automation of polarized matrix element computations in the publicly available Monte Carlo tool suite, MadGraph5_aMC@NLO. This enables scattering and decay simulations involving helicity-polarized asymptotic or intermediate states, preserving both spin-correlation and off-shell effects. As demonstrations of the method, we investigate the leading order production and decay of polarized weak gauge bosons in the process pp→jjWλ+Wλ′−, with helicity eigenstates (λ, λ′) defined in various reference frames. We consider the Standard Model at both O(α4) and O(α2αs2) as well as a benchmark composite Higgs scenario. We report good agreement with polarization studies based on the On-Shell Projection (OSP) technique. Future capabilities are discussed
Baryogenesis via Leptogenesis from Asymmetric Dark Matter Using Higher Dimension Operator
No full text
