We present recent observational bounds on dark energy constrained by the type Ia supernovae, cosmic microwave background, and baryon acoustic oscillations. We review a number of theoretical approaches that have been adopted so far to explain the origin of dark energy. This includes the cosmological constant, modified matter models (such as quintessence, k-essence), and modified gravity models...
The charged lepton flavor violating (CLFV) processes of $\mu^-e^-\rightarrow e^-e^-$ decay by four Fermi contact interactions in a muonic atom for various atoms are investigated. The wave functions of bound and scattering state leptons are properly treated by solving Dirac equations with Coulomb interaction of the finite nuclear charge distributions. This new effect contributes significantly...
We study the cosmological history of the classical conformal B−L gauge extension of the standard model, in which the physical scales are generated via the Coleman-Weinberg-type symmetry breaking. Especially, we consider the thermal phase transition of the U(1)B−L symmetry in the early universe and resulting gravitational-wave production. Due to the classical conformal invariance, the phase...
T2K (Tokai to Kamioka) is the world's first off-axis designed long-baseline experiment that was built for precision measurement of neutrino oscillations. The T2K experiment uses a high intensity, highly pure beam of muon (anti)neutrinos produced at J-PARC in Tokai, Japan. A Near Detector complex, 280 m downstream of the target, is operated to monitor and characterize the (anti)neutrino beam...
Cosmic rays have a measured energy spectrum which extends past 100 EeV, with ECM above 100 TeV. Their interactions in the atmosphere thus probe energies past the LHC, but without a controlled experimental environment and with a very low flux.
The Pierre Auger Observatory studies atmospheric cascades, produced by ultra-high energy cosmic rays, with a collecting area of 3000 square...
Searches for additional scalars and pseudoscalar with masses below the newly discovered higgs boson h(125) are performed at CMS experiment . These searches are motivated within several BSM theories, most significantly extensions of the mininal extensions of the MSSM like the NMSSM, where additional scalar and pseudoscalar states are expected. The mass range from 250 MeV to 110 GeV is explored...
Higgs-boson pair production is well known being capable to probe the trilinear self-coupling of the Higgs boson, which is one of the important ingredients of the Higgs sector itself. Pair production then depends on the top-quark Yukawa coupling gS,Pt, Higgs trilinear coupling λ3H, and a possible dim-5 contact-type ttHH coupling gS,Ptt, which may appear in some higher representations of the...
To determine bubble nucleation rates precisely, we need to evaluate functional determinants around the bounce background. In gauge theories, there appears a mixing between the would-be NG boson and the gauge boson, and it becomes quite difficult to see the gauge dependence of the functional determinant. Though the gauge independence of the effective action is proven by Nielsen at all orders,...
Direct detection of dark matter in which we can observe not only the recoil energy but also the direction, will be forthcoming generation project. I will discuss the possibility to measure the velocity distribution of dark matter using the directional detections. Especially, it is expected to be efficient to distinguish isotropic distribution models from non-isotropic ones.
The long-baseline neutrino experiment T2K uses one of the most intense and well understood GeV-scale neutrino sources in the world, combined with excellent detection capabilities using its near and far detectors. Beyond its primary goal of studying the standard 3-neutrino mixing model, it also provides an opportunity to search for exotic physics in the neutral lepton sector.
From both...
The Mu2e Experiment at Fermilab will search for coherent, neutrinoless conversion of muons into electrons in the field of a nucleus with a sensitivity improvement of a factor of 10,000 over previous experiments. Such a charged lepton flavor-violating reaction probes new physics at a scale inaccessible with direct searches at either present or planned high energy colliders. The experiment both...
It is known that chiral primordial gravitational waves (GWs) are provided due to the strong interaction of gauge fields to axions during inflation. Interestingly, in the case of non-Abelian gauge fields, they can produce chiral GWs at linear level. In this talk, we explain the mechanism of generating such chiral primordial GWs and discuss their detectability in future observations.
DeeMe is an experiment which aims to find a clear evidence of the existence of the new physics beyond the standard model by searching for one of the lepton flavor violating reactions, mu-e conversion at J-PARC MLF. The details of the experiment is presented in this talk.
We consider the tentative hint of Higgs boson decay h→μτ recently seen in LHC data in a grand unified theory framework which is based on the SU(5) gauge group and implements the principle of minimal flavor violation. This allows us to explore the possibility that this decay has some link to potential new physics in the quark sector. We look at different simple scenarios in this context and...
I will present recent Sunyaev-Zeldovich observations of clusters of galaxies with the
NIKA prototype at the IRAM 30-m telescope together with the forthcoming
tSZ observation program with the NIKA2 camera.
Neutrino interaction cross-section measurements on behalf of the T2K collaboration
We investigates how nontrivial topology affects the entanglement dynamics between a detector and a quantum field and between two detectors mediated by a quantum field. Nontrivial topology refers to both that of the \textit{base space}
and that of the \textit{bundle}. Using a derivative-coupling Unruh-DeWitt-like detector model interacting with a quantum scalar field in an Einstein...
First we give the formalism for heavy neutrino mixing with light neutrinos where we extend the SM to include n right-handed SM singlets along with the three generation of left-handed SM SU(2) doublets. We give the calculation of the four body decay $B_{c}^{-}\rightarrow J/\psi\ell_{1}^{-}\ell_{2}^{-}\pi^{+}$ and $B_{c}\rightarrow B_{s}^{0}\ell_{1}^{-}\ell_{2}^{-}\pi^{+}$. Explicit form of...
We perform the one-loop induced charged lepton flavor violating decays of the neutral Higgses in an extended mirror fermion model with non-sterile electroweak-scale right- handed neutrinos and a horizontal A4 symmetry in the lepton sector. We demonstrate that for the 125 GeV scalar h there is tension between the recent LHC result B(h → τμ) ∼ 1% and the stringent limits on the rare processes μ...
Axion-like particles (ALPs) can induce localised $\mathcal{O}(10 \%)$ oscillatory modulations in the spectra of photon sources passing through
astrophysical magnetic fields. Ultra-deep Chandra observations of the Perseus cluster contain
over $5 \times 10^5$ counts from the central AGN, NGC1275, and represent a dataset of extraordinary quality for ALP searches.
We use this dataset to search...
The COMET experiment intends to search for the lepton flavor-violating conversion of a muon to electron while in the orbit of an atomic nucleus. The process is not forbidden by any symmetry of the Standard Model, but remains extremely suppressed even when flavor-mixing neutrino masses are introduced, due to the relative smallness of these masses. Because this suppression is accidental in the...
Gamma-ray bursts (GRBs) are the most energetic explosion events in the universe.
An amount of gravitational energy of the order of the rest-mass energy of the Sun is
released from a small region within a short time.
This should lead to the formation of a fireball of temperature in the MeV range,
consisting of electrons/positrons, photons, and a small fraction of baryons.
We exploit the...
We are going to calculate the flow of the angular momentum and flux of the Hawking radiation in the rotating regular black hole with the time-delay proposed in arXiv:1510.08828, based on the anomaly cancellation. We first try to reduce the field theories to the infinite two-dimensional massless free models in which the anomaly cancellation method is possible, in the three metrics in...
We study the effects of D-brane instantons wrapping rigid cycles on the $Z_2 \times Z_2$ toroidal orbifold. We compute Majorana masses induced by rigid D-brane instantons and realize bimaximal mixing matrices in certain models. We can also derive more generic mass matrices in other models. The bimaximal mixing Majorana mass matrix provides a possibility for explaining observed mixing angles....
The muon anomalous magnetic moment is a fundamental quantity that has played an important role in the development of the Standard Model.It can be both measured and computed to very high precision, providing a sharp tool in testing the robustness of the SM and predictions by the theories of BSM physics. The previous measurement by the Brookhaven E821 experiment found a 3.6 standard deviation...
We consider two-Higgs doublet models (THDMs) with a supersymmetric UV completion. Contrary to the Standard Model, THDMs can be embedded in high-scale supersymmetry with a SUSY breaking scale as high as the scale of grand unification. The stability of the electroweak vacuum and experimental constraints point towards low values of tan(beta) < 2 and a pseudoscalar mass of at least about a TeV. If...
Nearly 80% of matter in the Universe is dark matter although its nature is as mysterious as its name. By using the dark matter in Inflationary Dark Matter model proposed by P. Q. Hung and P. Frampton, we examine the possibility of the formation of Dark Astronomical Compact Objects (DACOs) along with their physical properties such as masses, radii and their stability. We also propose an energy...
In this study, we obtain the light neutrino masses and mixings consistent with the experiments, in the democratic texture approach. The essential ansatz is that $\nu_{Ri}$ are assumed to transform as ``right-handed fields'' $\bf 2_{R} + 1_{R}$ under the $S_{3L} \times S_{3R}$ symmetry. The symmetry breaking terms are assumed to be diagonal and hierarchical. This setup only allows the normal...
LHC Run I discovered the Higgs boson and revealed that it has properties almost
predicted by the SM, like spin, parity and couplings to the other SM particles.
If there exists additional light bosons having the same quantum numbers with the Higgs boson, they will mix with it through the off-diagonal mass terms.
This mixings modify the couplings of the Higgs boson and also generate...
We perform an updated analysis for the one-loop induced lepton flavor violating radiative decays $l_i \to l_j \gamma$ in an extended mirror model. Mixing effects of the neutrinos and charged leptons constructed with a horizontal $A_4$ symmetry are also taken into account. Current experimental limit and projected sensitivity on the branching ratio of $\mu \to e \gamma$ are used to constrain...
Inflation due to a non-minimally coupled scalar field is in good agreement with the observed value of spectral index and constraints on the tensor-to-scalar ratio. Here we explore the possibility that non-minimally coupled inflation represents the late stage of a Universe which emerges from an early contracting era. We present a model in which the Universe smoothly transitions from an...
Electroweak multiplets are arguably among the simplest and best motivated WIMP dark matter candidates.
I will discuss their relevant phenomenology in the light of current and future experimental searches. Predictions for searches at the high-luminosity LHC, and at an 100 TeV pp collider will be presented. Then, I will analyze indirect detection probes. I will compare the predictions of the...
We consider a class of minimal abelian extensions of the Standard Model (SM) with an extra neutral gauge boson Z’ at the TeV scale. In these scenarios an extended scalar sector and heavy right-handed neutrinos are naturally envisaged. We present some of their striking signatures at the Large Hadron Collider, the most interesting
arising from a Z’ decaying to heavy neutrino pairs as well as...
SHIP is a new general purpose fixed target facility, whose Technical Proposal has been recently reviewed by the CERN SPS Committee, who recommended that the experiment proceeds further to a Comprehensive Design phase. In its initial phase, the 400GeV proton beam extracted from the SPS will be dumped on a heavy target with the aim of integrating $2\times 10^{20}$ pot in 5 years. A dedicated...
Within the framework of the Electroweak-scale right-handed neutrino (EW-$\nu_R$) model, we calculate the rate for $\mu \to e$ conversion with a particular aim at the sensitivities
of the upcoming experiments, Mu2e ($6 \times 10^{-17}$) and COMET ($3 \times 10^{-17}$). Our calculations show a direct relationship between the rate for $\mu \to e$ conversion and that for $\mu \rightarrow e...
In this talk, I will report on my [latest work][1] together with Tsutomu Yanagida on an interesting possibility to unify the dynamics of spontaneous supersymmetry breaking and cosmic inflation. Our model is based on strong gauge dynamics, explains the high supersymmetry breaking scale, and also provides an answer to the question "why is there such a thing as cosmic inflation in the first...
We study the sensitivity of top pair production and six-fermion decay at the LHC to the presence and nature of an underlying Z' boson, accounting for full tree-level Standard Model interference, with all intermediate particles allowed off-shell. We concentrate on the lepton-plus-jets final state and simulate experimental considerations, including kinematic requirements and top quark pair...
Lepton-number violating neutrinoless double-beta decay plays a major role in determining neutrino properties. If the neutrino has a Majorana nature, detection of neutrinoless double beta decay may provide insight into the neutrino mass. The MAJORANA Collaboration is constructing an ultra-low background, modular high-purity Ge detector array to search for this decay in 76Ge. Located at the...
The general strategy for dark matter (DM) searches at colliders currently
relies on simplified models, which typically have a limited number of free
parameters. In the case of $t$-channel colored mediators, these simplified
models often have assumptions on the chirality of the DM-SM interactions
with quarks, though generically a UV-complete model with such colored
mediators would lead...
We investigate aspects of axion as a coherently oscillating massive classical scalar field
by analyzing the fully nonlinear order perturbations in Einstein's gravity in the axion-comoving gauge.
The axion fluid has its characteristic pressure term leading to an axion Jeans scale
which is cosmologically negligible for a canonical axion mass.
Our classically derived axion pressure term...
Observation of non-zero neutrino masses at a scale $\sim 10^{-1} - 10^{-2}$ eV is a major problem in otherwise highly successful Standard Model. The most elegant mechanism to explain such tiny neutrino masses is seesaw mechanism with right handed neutrinos. However, the required seesaw scale is so high ($\sim 10^{14}$ GeV), it will not have any direct collider implications. Recently, in our...
In this report, we study lepton flavor violation in some typical scenarios of minimal lepton flavor violation (MLFV). We introduce briefly the MLFV models in the three following scenarios: i, the Standard Model (SM) field content basing on lepton flavor group $G_{LF}=SU(3)_L\times SU(3)_{E_R}$; the see-saw type I field contents with three heavy right-handed neutrinos, and the lepton flavor...
After the release of the PLANCK data, it is evident that inflationary paradigm has stood the test of time. Even though, it is difficult to realise inflationary paradigm in a particle physics model as the present observations have ruled out the simplest quartic and quadratic inflationary potentials, which generically arise in particle physics. We would show that such simplest inflationary...
nEXO is currently in a research and development phase of a 5 tons detector for searching neutrinoless double beta decay of enriched Xe136. The nEXO detector is based on the successfully running EXO200, which has reached a sensitivity for the half life of the decay of 1.9 x 10^25 years with an exposure of 99.8 kgyr. The nEXO experiment will reach a half life sensitivity of > 5 x 10^27 years and...
In our work, we investigate exclusion limits on the parameter space of the Non-Universal Gaugino Mass (NUGM) scenario
where a natural SUSY spectrum is achieved due to a relatively heavy wino mass parameter. We calculated the bound on the mass of top squark, which is almost right-handed and then it can decay into both $t \tilde{\chi}_{1,2}^0$ and $b \tilde{\chi}_1^{\pm}$. The top squark...
We study parameter degeneracies that can occur in long-baseline neutrino
appearance experiments due to nonstandard interactions (NSI) in neutrino propagation.
For a single off-diagonal NSI parameter, and neutrino and antineutrino measurements at a
single $L/E$, there exists a continuous four-fold degeneracy (related to the mass hierarchy and $\theta_{23}$ octant) that renders the mass...
A reformulation of inflationary model analyses appeared recently, in which inflationary observables are determined by the structure of a pole in the inflaton kinetic term rather than the shape of the inflaton potential.
This is called pole inflation, and it is a generalization of $\alpha$-attractors and $\zeta$-attractors.
The predicted values of inflationary observables are universal in the...
The PandaX dark matter experiment searches WIMP-nucleon scattering signals in the China JinPing Underground Laboratory (CJPL) with a rock burden of 2400 m, employing dual-phase xenon time projection chamber technology. After the completion of PandaX-I, the upgraded experiment, PandaX-II, has been equipped with a 580 kg active xenon target. A commissioning run was carried out in CJPL late in...
I discuss the Yukawa unification, in particular, the unification
of the Yukawa coupling constants of bottom and tau, in the
framework of supersymmetric (SUSY) model. I concentrate on the
model in which the SUSY breaking scalar masses are of the order
of the gravitino mass while the gaugino masses originate from the
effect of anomaly mediation and hence are one-loop suppressed
relative...
We revisit the compatibility between the chaotic inflation, which provides a natural solution to the initial condition problem, and the metastable electroweak vacuum, which is suggested by the results of LHC and the current mass measurements of top quark and Higgs boson. It is known that the chaotic inflation poses a threat to the stability of the electroweak vacuum because it easily generates...
In this talk, the present status of the experiment will be presented. A new exculusion limit and sensitivity for A NIT detector with an exposure of 1 kgxyear including directionality information will be presented.
Conventional wisdom relates the vacuum energy arising from the zero point fluctuations of quantum fields with the cosmological constant which is a parameter in Eidnstien's field equations. The basis of this relation is in the semi-classical approximation where gravity is treated classically. However, as is well known, the effective cosmological constant generated by the zero-point...
Observations at cosmological and astronomical scales indicate that the majority of matter in our Universe is in the form of non-relativistic and long-lived dark matter. Its observed relic abundance is consistent with the existence of a neutral, massive particle with little or no self-interaction. A dark matter candidate favoured by extensions of the Standard Model is a Weakly Interacting...
The Pierre Auger Observatory is the largest detector ever built. With an area covering over 3000 km2, it was designed for the detection of ultra high energy cosmic rays. Using an original hybrid technique the Observatory can measure both the longitudinal profile in the atmosphere and the lateral distribution of particles at the ground, which allows the study of the extensive air showers in two...
We will present main results of our recent study on higher dimensional scenarios of a ghost-free nonlinear massive gravity proposed by de Rham, Gabadadze, and Tolley (dRGT). In particular, a useful method, which is based on the Cayley-Hamilton theorem, to construct higher dimensional massive graviton terms will be presented. The constant-like behavior of massive graviton terms of...
Observational evidence for the existence of Dark Matter is limited to its gravitational effects. The extensive program for dedicated searches has yielded null results so far, challenging the most popular models. Here we propose that this is the case because the very existence of cold Dark Matter is a manifestation of gravity itself. Indeed, the only known ghost-free extension of General...
A photon is a fundamental particle, instead of a nonperturbative composite like hadrons. However, an energetic photon can fluctuate into vector mesons in the kinematic region with a small Bjorken variable x < 0.1. Particularly at x < 0.01, the hadronic contribution to cross sections of the electron–photon deep inelastic scattering dominates, and a photon can be regarded as a hadron rather than...
The essential point is that the mass of the lightest right-handed neutrino can be enhanced in the model because it has a lot of mass terms whose mass parameters are predicted to be the same order of magnitude which is smaller than $10^8$ GeV. We show that O(10) enhancement for the lightest right-handed neutrino mass is sufficient for the observed baryon asymmetry. Note that such mass...
The dual light-emitting crystals can reflect the different ranges of nuclear recoils and electron recoils by the ratio of the two different scintillation components. CsI(Na) crystals at temperatures of -160℃ have the best performance in several candidate crystals. An experiment called CINDMS is proposed for WIMPs direct searches based on the CsI(Na) crystals detector by IHEP. The 1T-scale...
WIMP Dark Matter generally assumes the Standard Model and Dark Matter form a single thermal bath at early time, with the Dark Matter relic density set by interactions between these two populations. Arguably, a more compelling assumption is that Dark Matter is not part of the Standard Model sector. Even if there are decoupled dark sectors, then it is a natural expectation that the visible and...
The TeV scale WIMP having a weak charge (e.g. Wino, Higgsino) recently attracts many attentions. While such a WIMP is hard to be detected at collider and direct dark matter detection experiments, it is expected to be efficiently searched for at indirect dark matter detection experiments, for its annihilation cross section is boosted by the Sommerfeld enhancement. Among various indirect...
I discuss a new axionic solution to the strong CP problem which involves a hypothetical vector-like quark(s) in a high-colour representation of the conventional QCD. There are two distinct scenarios. If the current mass of the exotic quark is zero, the strong CP phase can be trivially rotated away. The high-colour quark is `hidden' in various bounds states, the lightest being the composite...
Magnetic fluxes in extra dimensional space can be an origin of the flavor structure of the standard model. In particular, in higher-dimensional supersymmetric Yang-Mills (SYM) theories compactified on magnetized orbifolds, several MSSM-like models were constructed successfully.
In this work, we derive dynamical supersymmetry breaking models from a single SYM theory compactified on magnetized...
As Rubakov suggested in 1997, an QCD axion can be heavy if there is a copy of
the Standard Model and a Peccei-Quinn symmetry is realized between it and the
Standard Model.
Following that idea, we construct a concrete model which satisfies the cosmological
consistency.
Then, some of the resultant particles can be around the region which is accessible by
the LHC. We point out that the...
It has been shown that gravitational waves propagate through ideal fluids without experiencing any dispersion or dissipation. However, if the medium has a non-zero shear viscosity, gravitational waves will be dissipated at a rate proportional to Gη?. We test Dark Matter and Dark Energy models with non-zero shear viscosity by calculating the dissipation of GW150914 which propagates over a...
In this talk, we show the concrete embeddings of the standard model gauge groups into SO(32) gauge group in terms of the multiple U(1) fluxes. The correct matter contents of the standard model are then derived from the adjoint and vector representations of SO(12) given by the subgroup of SO(32).
Since the number of generations corresponds to the number of U(1) fluxes, we search for the...
We propose and study a holographic dual of the type IIB superstring theory of AdS_5xS^5 in terms of the N=4 superconformal Yang-Mills theory on dS_4. We review the bulk to boundary formalism to evaluate the boundary correlation functions. Then we present several non-local observables related to heavy quarks in the dual theory on dS_4.
We analyze constraints on parameters characterizing the pre-inflating universe in an open inflation model with a present slightly open $\Lambda_{\rm CDM}$ universe. We employ an analytic model to show that for a broad class of inflation-generating effective potentials, the simple requirement that some fraction of the observed dipole moment represents a pre-inflation isocurvature fluctuation...
Recently an SO(11) gauge-Higgs grand unified theory (GHGUT) in 5D Randall-Sundrum warped space was proposed in PTEP(2015)111B01(arXiv:1504.03817). In this framework, the 4D SM bosons and fermions are naturally realized by the SO(11) bulk gauge boson and SO(11) spinor bulk fermions, respectively. GHGUT leads to gauge coupling unification, so it is inevitable to discuss the renormalization group...
The OPERA experiment at the Gran Sasso underground laboratory has recently established nu_mu -> nu_tau oscillations in appearance mode with a significance of 5.1 sigma thanks to the observation of five signal candidate events in a sample with a signal-to-background
ratio of about ten. Now the nu_tau data analysis will be discussed, with emphasis on the background constraints obtained by using...
A search for resonances decaying to two photons was conducted with the ATLAS Experiment at the LHC. The analysis used proton-proton collision data with a center-of-mass energy of sqrt(s)=13 TeV and an integrated luminosity of 3.2/fb. Searches were performed for spin-0 particles at masses greater than 200 GeV and spin-2 particles at masses greater than 500 GeV. Limits on the production...
We report on the latest searches for low mass states predicted in several New Physics models performed with the data collected by the BaBar detector at the PEP-II e+e- collider. In particular we search for a new muonic dark force mediated by a gauge boson (Z') coupling only to the second and third lepton families. The existence of the Z' boson is probed in e+e- -> mu+mu- Z', Z’ -> mu+ mu-...
Under general circumstances, the Standard Model Higgs is excited in the form of a condensate during or towards the end of inflation. The Higgs condensate is then forced to decay afterwards — due to non-perturbative effects — into the rest of the SM species. I will present the cosmological implications of this primordial decay, quantifying the necessary conditions to achieve a successful...
Partially based on Phys.Rev.Lett. 115 (2015) no.18, 181104, in collaboration with Sourav Bhattacharya, Konstantinos F. Dialektopoulos, Antonio Enea Romano, Theodore N. Tomaras.
We investigate the possibility that the widely discussed $\sim 750$ GeV $\gamma\gamma$ excesses at the 2015 $13 TeV$ collisions at the LHC can be explained by the vector boson fusion production rather than the gluon-gluon fusion production which was assumed by most of the phenomenological models, by considering the available kinematics distributions from ATALS and CMS results. We propose a...
From compactification of E8xE8 heterotic string, I attempt to construct an extended GUT where families are unified. There appears an anti-SU(7) GUT group from which weak CP is calculated under the assumption of only one CP phase in the theory.
NOvA is a long-baseline accelerator-based neutrino oscillation experiment that is optimized for $\nu_\mu-\nu_e$ measurements. It uses the upgraded NuMI beam from Fermilab and measures $\nu_e$ appearance and $\nu_\mu$ disappearance at its Far Detector in Ash River, Minnesota. The $\nu_e$ appearance analysis at NOvA aims to resolve the neutrino mass hierarchy problem and to constrain the...
Flavour changing neutral current processes, such as B -> K(*)l+l- where l = e+, mu+, tau+ are highly suppressed in the Standard Model (SM). These rare decays occur at lowest order via 1-loop diagrams, and contributions from virtual particles in the loop allow one to probe large mass scales at relatively low energies. We present here the most recent results based on the full BABAR data...
Based on an article Published in Phys.Lett. B755 (2016) 464-468, in collaboration with Prof Misao Sasaki. director of the Yukawa Institute for Theoretical Physics(YITP), in Kyoto , Japan.
The diphoton excess at 750 GeV would make a definite signal of new physics beyond the Standard Model, if it is confirmed. We consider a possibility that the excess is due to a composite (pseudo)scalar boson, whose constituents are either new vector-like quarks ($Q\overline{Q}$) or scalar quarks
($\widetilde{Q} \widetilde{Q}^\dagger$) which feel new QCD-like vectorlike confining force
with...
The NA62 experiment at CERN SPS collected a large sample of charged kaon decays with a highly efficient trigger for decays into electrons in 2007 using the experimental setup of the earlier kaon experiment at CERN NA48/2. The kaon beam represents a source of tagged neutral pion decays in vacuum. A measurement of the electromagnetic transition form factor slope of the neutral pion in the...
Quantum field theory on curved space-times is a very powerful framework for the study of quantum phenomena in situations where gravitation itself can be treated classically. Of special interest is the study of interacting quantum fields in de Sitter space-time, where corrections computed using the standard perturbative expansion are plagued by contributions that secularly grow with time...
The neutrino mass hierarchy is one of the neutrino fundamental properties yet to be determined. We introduce a method to determine neutrino mass hierarchy by comparing the interaction rate of neutral current (NC) interactions, $\nu(\overline{\nu}) + p\rightarrow\nu(\overline{\nu}) + p$, and inverse beta decays (IBD), $\bar{\nu}_e + p\rightarrow n + e^+$, of supernova neutrinos in scintillation...
The Lorentz violation effects on the flavor transitions of high energy astrophysical neutrinos are studied. We show that stringent constraints on the Lorentz violation parameters can be derived from recent IceCube flavor ratio measurement on astrophysical neutrinos with energies between 25 TeV and 2.8 PeV. We present our results with both analytical approximations and full numerical calculations.
The Dirac-Born-Infeld (DBI) action play important roles in the context of string theory. In the string theory, an effective action of D-brane is described by a DBI-type action, which consists of Maxwell terms? as well as the ones of scalar fields in general. From a phenomenological and theoretical viewpoint, the embedding of the DBI action into supersymmetry (SUSY) or supergravity (SUGRA) is...
The observed Higgs mass indicates that its quartic coupling and beta function (and also bare mass) can simultaneously vanish around the Planck scale. Such a non-trivial behavior of the Higgs potential is called the criticality of the Standard Model. Here, we show that it can be explained based on the Coleman’s multi-local theory.
Motivated by the di-photon resonance recently reported by the ATLAS and CMS collaborations at 13 TeV, we interpret the resonance as a scalar boson X(750) in hidden-valley-like models. The scalar boson X can mix with the standard model Higgs boson and thus can be produced via gluon fusion. It then decays into a pair of very light hidden particles Y of sub-GeV, each of which in turn decays to a...
COHERENT
Coherent, elastic neutrino-nucleus scattering (CEvNS) was first predicted in 1974 as an essential process in the standard model of electroweak interactions. Forty-two years later it is still undetected. Taking advantage of technologies that have recently come to maturity, and the availability of a world-class pulsed neutrino source, the COHERENT collaboration seeks to make the...
The coupling of gravity to chiral quark-leptons is investigated in the Discretized Kaluza-Klein theory with a new Dirac operator and a new wedge product. It is reduced to the couplings of chiral quark-spinors to the ordinary gravity and the gauge fields together with new interaction terms.
In this talk I will first show how the relatively large effective couplings, required by the 750 GeV diphoton signal, can be the result of a threshold enhancement in the loop coupling between a heavy pseudoscalar particle and new leptons and quarks with masses of about 375 and 700 GeV, respectively. I will then present a model in which the new charged leptons avoid detection by decaying to a...
RENO (Reactor Experiment for Neutrino Oscillation) is designed to measure
the neutrino mixing angle theta_13 and the effective mass squared difference |dm^2_ee|
using electron anti-neutrinos from six reactors at Hanbit nuclear power plant in S. Korea.
RENO has been taking data since August 2011 using two identical detectors at near and far sites.
The unprecedented measurement of the...
Abstract: Electroweak scale right-handed neutrinos have become a commodity in recent years. Most scenarios involve the so-called sterile neutrino paradigm, where right-handed neutrinos are assumed to be completely neutral under the Standard Model gauge group. A more interesting possibility is - of course - one in which they do interact. Such a fertile (non-sterile) possibility is certainly...
GERDA is a low background experiment aimed for the serach of neutrinoless double beta ($0 \nu\beta\beta $) decay. The observation of such a process would demostrate the presence of a Majorana term in the neutrino mass and prove that lepton number is not conserved. The experimental setup is located at the LNGS underground laboratory of INFN in Italy. The search is performed with high purity...
Magnetic moments are forbidden for 2--component neutrinos (Weyl/Majorana), but transition moments are allowed ...and undistinguishable! Yet, triangular inequalities could help spot the difference! Leptogenesis is the most sturdy form of baryon number violation, but seems impossible to verify ...Discovering a right-handed W at a collider near you might falsify it!
The IceCube Neutrino Observatory, the world’s largest neutrino detector, has been fully operational at the Amundsen-Scott South Pole Station since 2011. IceCube has discovered a flux of high energy neutrinos of extraterrestrial origin, and the latest results on the characterization of this flux and investigations into its origin(s) will be presented. In addition, IceCube is sensitive to a...
The MEG experiment at PSI searched for the lepton-flavour violating decay mu -> e gamma with unprecedented sensitivity. The experiment ran for 5 years from 2009 to 2013 and it already set the most stringent experimental bound to date to be <5.7 x 10^-13 with an associated sensitivity of about 7.7 x 10^-13 from half of the statistics. I will present the MEG final result which has an associated...
Theories of massless higher spin gauge fields were seen as curiosities until recently. In the last decade or so these theories have played a larger role in string theory. I will give a broad overview of this subject and how the Vasiliev higher spin theory in AdS captures large N field theories in 2d and 3d. These are tractable yet nontrivial, often non-supersymmetric examples of the AdS/CFT...
In this talk we will give a bird view of the status Circular Electron Positron Collider (CEPC). The scientific goal and the collider design goal of CECP are described. The luminosity potentail of Super Proton-Proton Collider (SPPC) in the same tunnel of CEPC are also provided. The optimization of parameter designs for CEPC with different energies, machine lengthes, single ring and crab-waist...
We consider gravitational wave production by bubble collisions during a cosmological first-order phase transition. In the literature, such spectra have been estimated by simulating the bubble dynamics, under so-called thin-wall and envelope approximations in a flat background metric. How- ever, we show that, within these assumptions, the gravitational wave spectrum can be estimated in an...
The accelerated expansion of the universe is strongly manifested
after the discovery of unexpected reduction in the detected energy
fluxes coming from SNe Ia. Other observational data
like CMBR, LSS and galaxy redshift surveys also
provide evidences in this favor. These observations propose a
mysterious form of force, referred as dark energy (DE), which takes
part in the expansion...
Non-singular Bianchi-III and $VI_0$ string cosmological models filled with perfect fluid in the framework of $f(R,T)$ gravity are presented. The model initially accelerates for a certain period of time and decelerates thereafter. The physical behaviour
of the model is also studied.
