The $W$ boson mass recently reported by the CDF collaboration shows a deviation from the standard model prediction with an excess at $7σ$ level. We investigate two simple extensions of the standard model with an extra $U(1)$ dark sector. One is the $U(1)_x$ extension, where the $U(1)_x$ gauge field mixes with the standard model through gauge kinetic terms. The other is a general $U(1)_{\mathbf{A} Y+\mathbf{B} q}$ extension of the standard model. Fitting various experimental constraints we find the $U(1)_x$ extension with only kinetic mixing can enhance the $W$ boson mass for at most 10~MeV. While the $U(1)_{\mathbf{A} Y+\mathbf{B} q}$ extension can easily generate 77~MeV enhancement of the $W$ boson mass and also offer a viable dark matter candidate with mass ranging from several hundred GeV to TeV, which may be detected by future dark matter direct detection experiments with improved sensitivities.
We investigate a two Higgs doublet model with extra flavour depending $U(1)_X$ gauge symmetry where $Z'$ boson interactions can explain the Atomki anomaly by choosing appropriate charge assignment for the SM fermions. For parameter region explaining the Atomki anomaly we obtain light scalar boson with $\mathcal{O}(10)$ GeV mass, and we explore scalar sector to search for allowed parameter space. We then discuss anomalous magnetic dipole moment of muon and lepton flavour violating processes induced by Yukawa couplings of our model.
We propose a SUSY scenario to explain the current electron and muon $g-2$ discrepancies without introducing lepton flavor mixings. Threshold corrections to the Yukawa couplings can enhance the electron $g-2$ and flip the sign of the SUSY contributions. The mechanism predicts a flavor-dependent slepton mass spectrum. We show that it is compatible with the Higgs mediation scenario.
Motivated by results recently reported by the CMS Collaboration about an excess in the di-photon spectrum at about 96 GeV, especially when combined with another long-standing anomaly at the same value in the $b\bar b$ invariant mass spectrum in four-jet events collected at LEP, we show that a possible explanation to both phenomena can be found at 1$σ$ level in a generic 2-Higgs Doublet Model (2HDM) of Type-III in presence of a specific Yukawa texture, wherein Lepton Flavour Violating (LFV) (neutral) currents are induced at tree level. Bounds from Higgs data play a major role in limiting the pa…
We consider a simple extension of the Standard Model (SM) by a complex scalar doublet and a singlet along with three sterile neutrinos. The sterile neutrinos mix with the SM neutrinos to produce three light neutrino states consistent with the oscillation data and three heavy sterile states. The lightest sterile neutrino has lifetime longer than the age of the Universe and can provide correct dark matter relic abundance. Utilizing tree-level flavor changing interactions of a light scalar with mass~$\sim\mathcal{O}(100)$~MeV along with sterile neutrinos, we can explain the anomalous magnetic mom…
We study the effect of non-universal $Z'$ boson in the decay modes $B \to K π$. In the standard model these modes receive dominant contributions from $b \to s$ QCD penguins. Therefore, in this limit one expects $S_{π^0 K^0} \approx \sin 2 β$, $A_{π^0 K^0} \approx 0$ and $A_{π^0 K^-} \approx A_{π^+ K^-}$. The corrections due to the presence of small non-penguin contributions is found to yield $S_{π^0 K^0} > \sin 2 β$ and $ΔA_{CP}(K π) \simeq 2.5 %$. However, the measured value of $S_{π^0 K^0}$ is less than $ \sin 2 β$ and $ΔA_{CP}(K π) \simeq 15 %$. We show the model with a non-universal $Z'$ b…
We propose an extension of the standard model (SM) with $U(1)_{μ-τ}$ gauge symmetry, extra vectorlike quark doublets $Q'_a$ and singlet scalar $χ$, both of which are charged under $U(1)_{μ-τ}$ and carry {odd} dark $Z_2$ parity. Then assuming that $χ$ is the dark matter (DM) of the universe and imposing various constraints from dark matter search, flavor physics and collider search for $Q'_a$, one can show that radiative corrections to $b\rightarrow s Z^{'*} \rightarrow s l^+ l^- $ involving $Q'_a$ and $χ$ can induce $ΔC_9 \sim -1$ which can resolve the LHCb anomalies related with $B\to K^{(*)}…
We point out that in extended supersymmetric models such as supersymmetric left-right models, it is possible to have leptoquarks that explain the HERA high $Q^2$ anomaly without giving up R-parity conservation. The leptoquarks belong to vectorlike $(2, 2, \pm{4/3}, 3 or 3^*) $ representations of $SU(2)_L\times SU(2)_R\times U(1)_{B-L}\times SU(3)_c$ (denoted $G_{2213}$). Unlike the R-parity violating scenario, the leptoquarks are accompanied by new superpartners,the leptoquarkino which leads to many intersting signatures in other collider experiments. At Tevatron, pair productions of the lepto…
A non-universal $U(1)_{X}$ extension to the Standard Model composed of two scalar doublets and two scalar singlets together with three additional quark singlets and two lepton singlets and three generations of right-handed and Majorana neutrinos is made to explain lepton mass hierarchy, neutrino masses via inverse seesaw mechanism and muon anomalous magnetic moment in an anomaly free framework. In the present model, exotic and Standard Model particles acquire mass thanks to vacuum expectation values at different scales, yet the electron and the lightest neutrino are tree level massless but mas…
The Atomiki anomaly can be interpreted as a new light vector boson. If such a new particle exists, it could be a mediator between the Standard Model sector and the dark sector including the dark matter. We discussed some simple effective models with these particles. In the models, the secluded dark matter models are good candidates to satisfy the thermal relic abundance. In particular, we found that the dark matter self-interaction can be large enough to solve the small scale structure puzzles if the dark matter is a fermion.
Discrepancies between recent experimental results and their respective Standard Model predictions, known as flavour anomalies, are reported in semileptonic charged and neutral-current $B$-decays, the muon magnetic moment $(g-2)_μ$, and the extraction of the Cabibbo angle. In this proceedings, we review two New Physics models that introduce two scalar mediators at the TeV scale and aim at a combined explanation of the flavour anomalies. The first model features the leptoquarks $S_1$ and $S_3$ and provides tree level solutions to both $B$-anomalies and one-loop level solution to the anomalous $(…
The singly charged $SU(2)_L$ singlet scalar, with its necessarily flavour violating couplings to leptons, lends itself particularly well for an explanation of the Cabibbo Angle Anomaly and of hints for lepton flavour universality violation in $τ\to μ\bar νν$. In a setup addressing both anomalies, we predict loop-induced effects in $τ\to eγ$ and in $τ\to eμμ$. A recast of ATLAS selectron and smuon searches allows us to derive a coupling-independent lower limit of $\approx 200$ GeV on the mass of the singly charged singlet scalar. At a future $e^+e^-$ collider, dark matter mono-photon searches c…
The interaction of QCD and electroweak sector with gravity is characterized by the generation of a massless pole in a specific form factor present in the 1-loop effective action. We briefly illustrate how to single out this behaviour in perturbation theory, by taking as an example the $TJJ$ vertex, with $T$ denoting the energy momentum tensor of the Standard Model. The breaking of scale invariance, due to the trace anomaly, is then related to the appearance of a local degree of freedom in the effective action, which is of dilaton type.
A $6.8\,σ$ anomaly has been reported in the opening angle and invariant mass distributions of $e^+e^-$ pairs produced in ${^8Be}$ nuclear transitions. It has been shown that a protophobic fifth force mediated by a $17\,\textrm{MeV}$ gauge boson $X$ with pure vector current interactions can explain the data through the decay of an excited state to the ground state, ${^8Be^*} \to {^8Be}\, X$, and then the followed saturating decay $X \to e^+e^-$. In this work we propose a renormalizable model to realize this fifth force. Although axial-vector current interactions also exist in our model, their c…
Chiral perturbation theory in the anomaly sector for $N_f=2$ is extended to include dynamical photons, thereby allowing a complete treatment of isospin breaking. A minimal set of independent chiral lagrangian terms is determined and the divergence structure is worked out. There are contributions from irreducible and also from reducible one-loop graphs, a feature of ChPT at order larger than four. The generating functional is non-anomalous at order $e^2p^4$, but not necessarily at higher order in $e^2$. Practical applications to $γπ\toππ$ and to the $π^0\to2γ$ amplitudes are considered. In the …
The SUSY contributions $Δa_μ$ to muon $g-2$ anomaly can not even reach $3σ$ in ordinary gauge mediated SUSY breaking (GMSB) scenarios because of the strong correlations between the colored sparticle masses and the uncolored EW sparticle masses. An interesting extension to GMSB is the (Extra)Ordinary Gauge Mediation (EOGM), which can relax the correlations between squarks and sleptons with non-universal choices for $N_{eff,3}$ and $N_{eff,2}$. We find that EOGM scenarios with $N_{eff,3}\ll N_{eff,2}$ can explain the muon $g-2$ anomaly within $3σ$ range, however can not explain the new W-boson m…
Recently, deviations in flavor observables of B -> D(*) tau nu have been shown between the predictions in the Standard Model and the experimental results reported by BaBar, Belle, and LHCb collaborations. One of the solutions to this anomaly is obtained in a class of leptoquark model with a scalar leptoquark boson S_1, which is a SU(3)_c triplet and SU(2)_L singlet particle with -1/3 hypercharge interacting with a quark-lepton pair. With well-adjusted couplings, this model can explain the anomaly and be compatible with all flavor constraints. In such a case, the S_1 boson can be pair-produced …
We address the observed discrepancies in the anomalous magnetic dipole moments (MDM) of the muon and electron by extending the inert two Higgs Doublet Model (2HDM) with SM gauge singlet complex scalar field and singlet Vector-like Lepton (VLL) field. We obtain the allowed parameter space constrained from the Higgs decays to gauge Bosons at LHC, LEP II data and electro-weak precision measurements. The muon and electron MDM's are then explained within a common parameter space for different sets of allowed couplings and masses of the model particles.
The determinations of the Cabibbo angle from kaon, pion, $D$ and tau decays disagree with the one from super-allowed beta decays. The resulting $\approx 3\,σ$ deficit in first row (but also first column) CKM unitarity is known as the Cabibbo angle anomaly (CAA). Determining $V_{ud}$ from beta decays requires knowledge of the Fermi constant $G_F$, usually extracted from muon decay. However, because new physics might also affect muon decay, and thus the determination of the Fermi constant, an interesting interplay with the global electroweak fit arises where $G_F$ is a crucial input. In these pr…
The Cabibbo-Cobayashi-Maskawa (CKM) matrix parametrizes the misalignement between the up- and down-quark mass basis in the Standard Model (SM). The observation of first row CKM unitarity violation has recently emerged as a new anomaly of the SM, known as the "Cabibbo Angle Anomaly" (CAA). With current measurements, comparing the elements $V_{ud}$ and $V_{us}$ extracted from beta and kaon decays respectively, the tension with the SM prediction amounts to $\sim$$3\,σ$. Recently, it has been pointed out that this anomaly can also be seen as a discrepancy in the determination of the Fermi constant…
The ATLAS and CMS collaborations recently reported indication of a Higgs boson around 125 GeV. If we add extra vector-like quarks to the MSSM, such a relatively heavy Higgs can be naturally realized in the GMSB framework, simultaneously explaining the muon g-2 anomaly. I will discuss LHC prospects of this attractive model.
I provide a minimal method for generating a mu term and positive slepton masses within the framework of anomaly mediation. I introduce a new operator involving a hidden sector U(1) gauge field which is then canceled against a Giudice-Masiero-like mu term. No new flavor violating operators are allowed. This procedure produces viable electroweak symmetry breaking in the Higgs sector. Only a single pair of new vector-like messenger fields is needed to correct the slepton masses by deflecting them from their anomaly mediated trajectories. This model is minimal but it requires fine-tuning.
We present a simple general framework for realistic models of supersymmetry breaking driven by anomaly mediation. We consider a 5-dimensional "brane universe" where the visible and hidden sectors are localized on different branes, and the standard model gauge bosons propagate in the bulk. In this framework there can be charged scalar messengers that have contact interactions with the hidden sector, either localized in the hidden sector or in the bulk. These scalars obtain soft masses that feed into visible sector scalar masses at two loop order via bulk gauge interactions. This contribution is…
Original Georgi-Machacek model can preserve the custodial symmetry at tree level after the electroweak symmetry breaking. Unless additional $SU(2)_c$ custodial symmetry breaking effects are significant, the new physics contributions to $Δm_W$ are always very small. Our numerical results show that ordinary GM model can contribute to $Δm_W$ a maximal amount $0.0012$ GeV, which can not explain the new CDF-II anomaly on W boson mass. We propose firstly to introduce small misalignment among the triplet VEVs to increase $Δm_W$, which can give large new physics contributions to $Δm_W$. Such slightly …
We present a model of supersymmetry breaking mediated through a small extra dimension. Standard model matter multiplets and a supersymmetry-breaking (or ``hidden'') sector are confined to opposite four-dimensional boundaries while gauge multiplets live in the bulk. The hidden sector does not contain a singlet and the dominant contribution to gaugino masses is via anomaly-mediated supersymmetry breaking. Scalar masses get contributions from both anomaly mediation and a tiny hard breaking of supersymmetry by operators on the hidden-sector boundary. These operators contribute to scalar masses at …
Partial Split Supersymmetry with violation of R-parity as a model for neutrino masses is explored. It is shown that at the one-loop level the model can give predictions that are in agreement with all present experimental values for the neutrino sector. An analytical result is that the small solar neutrino mass difference can be naturally explained in the decoupling limit for the heavy Higgs mass eigenstates.
We consider a simple setup with light squarks which is free from the gravitino and SUSY flavor problems. In our setup, a SUSY breaking sector is sequestered from the matter and gauge sectors, and it only couples to the Higgs sector directly with $\mathcal{O}(100)\,$TeV gravitino. Resulting mass spectra of sfermions are split: the first and second generation sfermions are light as $\mathcal{O}(1)\,$TeV while the third generation sfermions are heavy as $\mathcal{O}(10)\,$TeV. The light squarks of $\mathcal{O}(1)\,$TeV can be searched at the (high-luminosity) LHC and future collider experiments. …
The tension among measurements of $V_{us}$ from different channels, the so-called Cabibbo Angle Anomaly, can be interpreted as a signal of lepton flavor universality (LFU) violation in the $W$ boson couplings. We investigate this issue in the framework of effective field theory, keeping the gauge structure of the Standard Model (SM) unchanged. We introduce gauge-invariant dimension-6 effective operators that couple the Higgs doublet to leptons, thereby giving non-universal tree-level contributions to the couplings of electroweak gauge bosons. Due to the $SU(2)_L$ gauge symmetry, a tension aris…
We propose to realize (natural) NMSSM spectrum from deflected AMSB with new messenger-matter interactions. With additional messenger-matter interactions involving ${\bf 10}\oplus{\bf \overline{10}}$ representation messengers, the muon g-2 anomaly can be solved at $2σ$ (or $3σ$) level with the corresponding gluino mass range $2.8~{\rm TeV}<m_{\tilde{g}}<5.4~ {\rm TeV}$ (or $2.6 ~{\rm TeV}<m_{\tilde{g}}<7.3~ {\rm TeV}$). Besides, our scenario is fairly natural within which the involved fine tuning can be as low as 47. So, in the framework of AMSB-type scenarios, NMSSM can be advantageous in expl…
We reinterpret anomaly-mediated supersymmetry breaking from a field-theoretic perspective in which superconformal anomalies couple to either the chiral compensator or the $U(1)_R$ vector superfield. As supersymmetry in the hidden sector is spontaneously broken by non-vanishing vacuum expectation values of the chiral compensator F-term and/or the $U(1)_R$ vector superfield D-term, the soft breakdown of supersymmetry emerges in the visible sector. This approach is physically more understandable compared with the conventional approach where the chiral compensator is treated on the same footing as…
The most statistically significant hints for new physics in the flavor sector are discrepancies between theory and experiment in $B$ decays to lepton pairs ($b\to s\ell^+\ell^-$) and a deficit in $1^{\rm st}$ row CKM unitarity (the Cabibbo Angle anomaly). We propose that these anomalies can be reconciled by a simplified model with massive gauge bosons transforming in the adjoint representation of $SU(2)_L$. After calculating the impact of this model on $B$ decays, observables testing charged current lepton flavor universality (LFU), electro-weak precision observables and LHC searches we perfor…
We study anomaly mediation models with gauge mediation effects from messengers which have a general renormalizable mass matrix with a supersymmetry-breaking spurion. Our models lead to a rich structure of supersymmetry breaking terms in the visible sector. We derive sum rules among the soft scalar masses for each generation. Our sum rules for the first and second generations are the same as those in general gauge mediation, but the sum rule for the third generation is different because of the top Yukawa coupling. We find the parameter space where the tachyonic slepton problem is solved. We als…
For the newly discovered $W$-boson mass anomaly, one of the simplest dark matter (DM) models that can account for the anomaly without violating other astrophysical/experimental constraints is the inert two Higgs doublet model, in which the DM mass ($m_{S}$) is found to be within $\sim 54-74$ GeV. In this model, the annihilation of DM via $SS\to b\bar{b}$ and $SS\to WW^{*}$ would produce antiprotons and gamma rays, and may account for the excesses identified previously in both particles. Motivated by this, we re-analyze the AMS-02 antiproton and Fermi-LAT Galactic center gamma-ray data. For the…
We consider an explanation of CDF II W bosom mass anomaly by $Z-Z'$ mixing with $U(1)_R$ gauge symmetry under which right-handed fermions are charged. It is found that $U(1)_R$ is preferred to be leptophobic to accommodate the anomaly while avoiding other experimental constraints. In such a case we require extra charged leptons to cancel quantum anomalies and the SM charged leptons get masses via interactions with the extra ones. These interactions also induce muon $g-2$ and lepton flavor violations. We discuss muon $g-2$, possible flavor constraints, neutrino mass generation via inverse seesa…
The present work introduces new scalar and fermionic degrees of freedom to the Standard Model. While the scalar sector is augmented by a complex scalar triplet and a doubly charged scalar singlet, the fermionic sector is extended by two copies of vector-like leptons. Of these, one copy is an $SU(2)_L$ singlet while the other, an $SU(2)_L$ doublet. We explain how this combination can offer a solution to the muon g-2 anomaly and also lead to non-zero neutrino masses. In addition, it is also shown that the parameter regions compliant with the two aforementioned issues can stabilise the electrowea…
Neutrinos may be the harbingers of new dark sectors, since the renormalizable neutrino portal allows for their interactions with hidden new physics. We propose here to use this fact to connect the generation of neutrino masses to a light dark sector, charged under a new $U(1)_{\cal D}$ dark gauge symmetry. We introduce the minimal number of dark fields to obtain an anomaly free theory with spontaneous breaking of the dark symmetry, and obtain automatically the inverse seesaw Lagrangian. In addition, the so-called $μ$-term of the inverse seesaw is dynamically generated and technically natural i…
We investigate the phenomenology of the Nearly Minimal Supersymmetric Standard Model (nMSSM) in the deflected anomaly mediation scenario. We also include the Fayet-Iliopoulos D-term of the standard model gauge group. In the nMSSM, the mu term is replaced by the vacuum expectation value of the gauge singlet; therefore, there is no difficulty in generating the B-term of the SUSY breaking scale. Although the messenger sector is introduced, direct couplings between nMSSM fields and messenger sector fields are forbidden by the discrete symmetry. Therefore, the phenomenology at the weak scale does n…
We investigate a modification of anomaly-mediated supersymmetry breaking (AMSB) with an exotic U(1)_x gauge sector that can solve the tachyonic slepton problem of minimal AMSB scenarios. The new U(1)_x multiplet is assumed to couple directly to the source of supersymmetry breaking, but only indirectly to the minimal supersymmetric Standard Model (MSSM) through kinetic mixing with hypercharge. If the MSSM sector is also sequestered from the source of supersymmetry breaking, the contributions to the MSSM soft terms come from both AMSB and the U(1)_x kinetic coupling. We find that this arrangemen…
In this paper we study the effects of $s\to d + 2{gluon}$ on $K_L \to γγ$ in the Standard Model. We find that this interaction can induce new sizeable SU(3) and U(3) nonet breaking effects in $K_L - η, η'$ transitions and therefore in $K_L\to γγ$ due to large matrix elements of $<η(η')|α_s G^a_{μν} \tilde G_a^{μν}|0>$ from QCD anomaly. These new effects play an important role in explaining the observed value. We also study the effects of this interaction on the contribution to $Δm_{K_L-K_S}$.
We present a supersymmetric extension of the Standard Model in which the new physics contributions to the anomalous magnetic moment of the muon can be more than an order of magnitude larger than in the minimal supersymmetric Standard Model. The extended electroweak symmetry breaking sector of the model can consistently accommodate Higgs bosons and Higgsinos with $O(1)$ couplings to muons. We find that sleptons with masses in the multi-TeV range can comfortably explain the recently confirmed discrepancy in the anomalous magnetic moment of the muon. We discuss additional phenomenological aspects…
We propose an explanation to the new W mass measurement recently reported by the CDF collaboration, which is larger than the standard model expectation by about 7 standard deviations. To alleviate the tensions that are imposed on the electroweak sector by the new W mass measurement, we carry out an analysis in the Stueckelberg extended standard model where a new neutral gauge boson appears which mixes with the two neutral gauge bosons in the electroweak sector both via the Stueckelberg mass terms and via the gauge invariant Stueckelberg-Higgs portal interaction and spoils the custodial symmetr…
We consider anomaly cancelations in Type IIB orientifolds on T^4/Z_N with quantized NS-NS sector background B-flux. For a rank b B-flux on T^4 (b is always even) and when N is even, the cancelation requires a 2^{b/2} multiplicity of states in the 59-open string sector. We identify the twisted sector R-R scalars and tensor multiplets which are involved in the Green-Schwarz mechanism. We give more details of the construction of these models and argue that consistency with the 2^{b/2} multiplicity of 59-sector states requires a modification of the relation between the open string 1-loop channel m…
In the scenario with a multiplicity of sectors which independently break supersymmetry, multiplicity of goldstini are predicted. We propose a new interpretation of the electron recoil excess at 2-7 keV observed in the XENON1T experiment with very long-lived goldstini DM elastically scattering off the electrons. The goldstini DM can be boosted by the late-decay of the other nearly degenerate (long-lived) goldstini DM, with their tiny mass difference being converted into kinetic energy of the lighter goldstini DM and neutrinos. We show that viable parameter space can be found which can explain t…
Analysis of EDGES data shows an absorption signal of the redshifted 21-cm line of atomic hydrogen at $z\sim 17$ which is stronger than expected from the standard $Λ$CDM model. The absorption signal interpreted as brightness temperature $T_{21}$ of the 21-cm line gives an amplitude of $-$500$_{-500}^{+200}$ mK at 99\% C.L. which is a 3.8$σ$ deviation from what the standard $Λ$CDM cosmology gives. We present a particle physics model for the baryon cooling where a fraction of the dark matter resides in the hidden sector with a $U(1)$ gauge symmetry and a Stueckelberg mechanism operates mixing the…
We propose a model to explain several muon-related experimental anomalies and the abundance of dark matter. We introduce an vector-like exotic lepton that form an iso-doublet and three right-handed Majorana fermions as an iso-singlet. A real/complex scalar field is added as a dark matter candidate. We impose a global $U(1)_ μ$ symmetry under which fields associated with the SM muon are charged. To stabilize the dark matter, we impose a $Z_2$ (or $Z_3$) symmetry under which the exotic lepton doublet and the real (or complex) scalar field are charged. We find that the model can simultaneously ex…
We assume a dark $U_{D}$ symmetric hidden sector and explore its possible content such that neutrino mass and Dark Matter are generated through the scotogenic mechanism. The hidden sector is considered analogue to the Standard Model, namely the charge assignment of hidden fermions is chiral and anomaly-free. Moreover, $U_{D}$ is assumed broken by an only Higgs singlet that also generates masses to all hidden fermions, therefore the charge assignment is subjected to additional restriction. We search by computer program for charge assignments satisfying all these conditions, and identify the res…
Within the model based on the $SU (2)_L\times SU (2)_R\times U (1)_{B-L} $ gauge group and having the bidoublet and two triplets of the Higgs fields (left-right model) the Higgs sector impact on the value of the muon anomalous magnetic moment is considered. The contributions coming from the doubly charged Higgs bosons, the singly charged Higgs bosons and the lightest neutral Higgs boson are taken into account. The obtained value of the muon anomalous magnetic moment is the function of the Higgs boson masses and the Higgs boson couplings constants (CC's). We express the most of part of the CC's…
Motivated by the $R_K$ and $R_{K^*}$ anomalies from B decays, we extend the minimal supersymmetric model with a non-universal anomaly-free $U(1)^\prime$ gauge symmetry, coupling non-universally to the lepton sector as well as the quark sector. In particular, only the third generation quarks are charged under this $U(1)^\prime$, which can easily evade the dilepton bound from the LHC searches. An extra singlet is introduced to break this $U(1)^\prime$ symmetry allowing for the $μ$-term to be generated dynamically. The relevant constraints of $B_s-\bar{B}_s$ mixing, $D^0-\bar{D}^0$ mixing and the…
Motivated by the simple toroidal compactification of extra-dimensional SUSY theories, we investigate on a partially $N=2$ supersymmetric (SUSY) extension of the standard model which has an $N=2$ SUSY sector and an $N=1$ SUSY sector. We point out that below the scale of the partially breaking of $N=2$ to $N=1$, the ratio of Yukawa to gauge couplings embedded in the original $N=2$ gauge interaction in the $N=2$ sector becomes greater due to a fixed point. Since at the partially breaking scale the sfermion masses in the $N=2$ sector is suppressed due to the $N=2$ non-renormalization theorem, the …
We elaborate on the structure of the graviton-gauge-gauge vertex in the electroweak theory, obtained by the insertion of the complete energy-momentum tensor ($T$) on 2-point functions of neutral gauge currents ($VV'$). The vertex defines the leading contribution to the effective action which accounts for the conformal anomaly and related interaction between the Standard Model and gravity. The energy momentum tensor is derived from the curved spacetime Lagrangian in the linearized gravitational limit, and with the inclusion of the term of improvement of a conformally coupled Higgs sector. As in…
In anomaly-mediated supersymmetry breaking, superpartners in a hidden sector have masses that are proportional to couplings squared, and so naturally freeze out with the desired dark matter relic density for a large range of masses. We present an extremely simple realization of this possibility, with WIMPless dark matter arising from a hidden sector that is supersymmetric QED with N_F flavors. Dark matter is multi-component, composed of hidden leptons and sleptons with masses anywhere from 10 GeV to 10 TeV, and hidden photons provide the thermal bath. The dark matter self-interacts through hid…
Explaining the $B \to Kμ^+μ^-$ Anomaly in the Left-Right Inverse Seesaw Model
División de Ciencias e Ingenierías, Universidad de Guanajuato（瓜纳华托大学科学与工程学院）；Centre for Theoretical Physics, Zewail City of Science and Technology（泽维尔科学与技术城理论物理中心）
Anomaly-mediated Scalar Gravitational Interactions and the Coupling of Conformal Sectors
Dipartimento di Matematica e Fisica, Università del Salento（萨伦托大学数学与物理系）；INFN Sezione di Lecce（意大利国家核物理研究所莱切分部）；National Center for HPC, Big Data and Quantum Computing（高性能计算、大数据与量子计算国家中心）；CNR-nanotec, Lecce（国家研究委员会纳米技术研究所莱切分部）
A systematic method developed by the authors to evaluate the one-loop electromagnetic self-energies of the low-lying mesons is extended to the calculation of the vector sector including $ρ$, $ω$, and $ϕ$-mesons. The theoretical result of $ρ^0-ρ^\pm$ electromagnetic mass difference is in agreement with the measurements. An interesting effect called as electromagnetic mass anomaly of the massive Yang-Mills particles is further discussed. There is no new parameter in this study.
We consider an extension of the Standard Model with an extra gauged $U(1)'$ symmetry in presence of a 2-Higgs Doublet Model structure of the scalar sector. We show that this scenario is able to explain the anomaly observed by the Atomki collaboration in the decay of an excited state of Beryllium via a light spin-1 $Z'$ with a mass of 17 MeV.
We show that the recent discovery of a new boson at the LHC, which we assume to be a Higgs boson, and the observed enhancement in its diphoton decays compared to the SM prediction, can be explained by a new doublet of charged vector bosons from an extended electroweak gauge sector model with SU(3)$_C\otimesSU(3)_L\otimesU(1)_X$ symmetry. Our results show a good agreement between our theoretical expected sensitivity to a 126--125 GeV Higgs boson and the experimental significance observed in the diphoton channel at the 8 TeV LHC. Effects of an invisible decay channel for the Higgs boson are also…
