Related papers: Reconstructing a light pseudoscalar in the Type-X …
In supersymmetric models with R parity violation, constraints on superpartner masses are significantly weaker than in models which conserve R parity. We find in regions of parameter space where a neutral gaugino or third generation scalar…
In order to reproduce the measured mass of the Higgs boson mh = 125GeV in the minimal supersymmetric standard model, one usually has to rely on heavy stops, increasing the fine tuning of the electroweak scale. By introducing a new gauge…
We show the reinterpretation of existing searches for exotic decays of the Standard Model (SM)-like Higgs, $H \to aa (hh)$, in various final states, in the framework of the 2-Higgs Doublet Model (2HDM) Type-I. We then explore a new search…
We review recent progress in techniques for searching for the Standard Model light `Intermediate Mass' Higgs Boson ($80 \GeV \lsim M_H \lsim 140\GeV$). We pay particular attention to associated production at the SSC and LHC where we search…
A search for a hypothetical heavy scalar particle, $X$, decaying into a singlet scalar particle, $S$, and a Standard Model Higgs boson, $H$, using 140 fb$^{-1}$ of proton-proton collision data at the centre-of-mass energy of 13 TeV recorded…
A search is performed for dark matter produced in association with bottom quarks and a pair of electrons or muons in data collected with the CMS detector at the LHC, corresponding to 138 fb$^{-1}$ of integrated luminosity of proton-proton…
In models with multiple nondegenerate Higgs bosons, the decay chain $H/A \to A/H Z\to t\bar{t} Z$ may have a partial width comparable to the $t\bar{t}$ decay mode. We recast the ATLAS standard model $t\bar{t} Z$ measurement to put limits on…
A charged Higgs in the type II two-Higgs-doublet model (THDM) has been bounded to be above a few hundred GeV by the radiative $B$ decays. A Higgs triplet extension of the THDM not only provides an origin of neutrino masses and a completely…
We propose a minimal extension of the Standard Model by two real singlet fields that could provide a good candidate for light Dark Matter, and give a strong first order electroweak phase transition. As a result, there are two CP even…
We search for the decay Y(1S) -> gamma A0, A0 -> gg or ss-bar, where A0 is the pseudoscalar light Higgs boson predicted by the next-to-minimal supersymmetric standard model. We use a sample of (17.6 +- 0.3)x 10^6 Y(1S) mesons produced in…
A search for dark matter particles produced in association with a Higgs boson decaying into a pair of $\tau$ leptons is performed using data collected in proton-proton collisions at a center-of-mass energy of 13 TeV with the CMS detector.…
We present numerical calculations of the photon-light-pseudoscalar-boson conversion in the recently discovered binary pulsar system J0737-3039. Light pseudoscalar bosons (LPBs) oscillate into photons in the presence of strong magnetic…
A search for the decay to a pair of new particles of either the 125 GeV Higgs boson ($h$) or a second CP-even Higgs boson ($H$) is presented. The dataset correspods to an integrated luminosity of 20.3 fb$^{-1}$ of $pp$ collisions at…
Axion-like particles (ALPs), relatively light (pseudo-)scalars coupled to two gauge bosons, are a common feature of many extensions of the Standard Model. Up to now there has been a gap in the sensitivity to such particles in the MeV to 10…
We present a comprehensive analysis of observing a light Higgs boson in the mass range $70$ -- $110$ GeV at the 13/14 TeV LHC, in the context of the type-I two-Higgs-doublet model. The decay of the light Higgs to a pair of bottom quarks is…
We study a limit of the nearly-Peccei-Quinn-symmetric Next-to-Minimal Supersymmetric Standard Model possessing novel Higgs and dark matter (DM) properties. In this scenario, there naturally co-exist three light singlet-like particles: a…
We performed a search for a light pseudoscalar particle $X$ in the decay $K_L^0->pi0pi0X$, $X->\gamma\gamma$ with the E391a detector at KEK. Such a particle with a mass of 214.3 MeV/$c^2$ was suggested by the HyperCP experiment. We found no…
We show that a general two-Higgs-doublet model (THDM) with a very light CP-odd scalar (A) can be compatible with the rho parameter, Br(b --> s\gamma), R_b, A_b, (g-2) of muon, Br(Upsilon --> A gamma), and the direct search via the Yukawa…
We extend the two-Higgs doublet models of Type I and Type II by adding a real gauge-singlet scalar S dark matter candidate (2HDMS models). We impose theoretical constraints deriving from perturbativity, stability, unitarity and correct…
A search for decays of the Higgs boson into a $Z$ boson and a light resonance, with a mass of 0.5-3.5 GeV, is performed using the full 140 fb$^{-1}$ dataset of 13 TeV proton-proton collisions recorded by the ATLAS detector during Run 2 of…