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Planck isocurvature constraint on primordial black holes lighter than a kiloton
Authors:
TaeHun Kim,
Jinn-Ouk Gong,
Donghui Jeong,
Dong-Won Jung,
Yeong Gyun Kim,
Kang Young Lee
Abstract:
We demonstrate that primordial black holes (PBHs) lighter than $10^9 \, \text{g}$, which evaporated before the big bang nucleosynthesis, can induce significant isocurvature perturbations due to their biased clustering amplitude and the branching ratio of the Hawking radiation differing from the abundance ratio. By leveraging the upper bound on the isocurvature perturbations from the cosmic microwa…
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We demonstrate that primordial black holes (PBHs) lighter than $10^9 \, \text{g}$, which evaporated before the big bang nucleosynthesis, can induce significant isocurvature perturbations due to their biased clustering amplitude and the branching ratio of the Hawking radiation differing from the abundance ratio. By leveraging the upper bound on the isocurvature perturbations from the cosmic microwave background anisotropies reported by the Planck collaboration, we derive a new upper bound on the abundance of these light PBHs in the presence of primordial non-Gaussianity as a working example.
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Submitted 7 August, 2026; v1 submitted 18 March, 2025;
originally announced March 2025.
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Charged Higgs Boson Phenomenology in the Dark Z mediated Fermionic Dark Matter Model
Authors:
Kyu Jung Bae,
Jinn-Ouk Gong,
Dong-Won Jung,
Kang Young Lee,
Chaehyun Yu,
Chan Beom Park
Abstract:
We present the phenomenology of the charged Higgs boson $H^\pm$ appearing in a fermionic dark matter model mediated by an additional scalar doublet. In order to couple the dark matter fermion to the scalar doublet, we introduce a U(1)$_X$ gauge symmetry, which is spontaneously broken at electroweak symmetry breaking, resulting in a massive $Z'$ gauge boson. Since $Z'$ is generically light, the mod…
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We present the phenomenology of the charged Higgs boson $H^\pm$ appearing in a fermionic dark matter model mediated by an additional scalar doublet. In order to couple the dark matter fermion to the scalar doublet, we introduce a U(1)$_X$ gauge symmetry, which is spontaneously broken at electroweak symmetry breaking, resulting in a massive $Z'$ gauge boson. Since $Z'$ is generically light, the model is subject to strong constraints from electroweak precision observables. As a result, the charged Higgs boson mass allowed by current experimental bounds is typically light in this model, 110 GeV $<m_{H^\pm}<$ 170 GeV. Such a light charged Higgs boson will be produced mainly through top-quark decays at the LHC. Additionally, depending on the mass of the additional neutral Higgs boson $h$ and the dark gauge boson $Z'$, the direct production channels $pp \to H^\pm Z'$ and $pp \to H^\pm h$ can become sizable. We investigate the corresponding signal processes at the LHC to assess the discovery potential for $H^\pm$. Current ATLAS and CMS searches for light charged Higgs bosons already impose further constraints on the model. We also discuss the implications of dark matter in relation to the charged Higgs boson phenomenology.
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Submitted 20 December, 2025; v1 submitted 11 September, 2024;
originally announced September 2024.
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Higgs Boson Precision Analysis of the Full LHC Run 1 and Run 2 Data
Authors:
Yongtae Heo,
Dong-Won Jung,
Jae Sik Lee
Abstract:
We perform global fits of the Higgs boson couplings to the full Higgs datasets collected at the LHC with the integrated luminosities per experiment of approximately 5/fb at 7 TeV, 20/fb at 8 TeV, and up to 139/fb at 13 TeV. Our combined analysis based on the experimental signal strengths used in this work and the theoretical ones elaborated for our analysis reliably reproduce the results in the li…
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We perform global fits of the Higgs boson couplings to the full Higgs datasets collected at the LHC with the integrated luminosities per experiment of approximately 5/fb at 7 TeV, 20/fb at 8 TeV, and up to 139/fb at 13 TeV. Our combined analysis based on the experimental signal strengths used in this work and the theoretical ones elaborated for our analysis reliably reproduce the results in the literature. We reveal that the LHC Higgs precision data are no longer best described by the SM Higgs boson taking account of extensive and comprehensive CP-conserving and CP-violating scenarios found in several well-motivated models beyond the SM. Especially, in most of the fits considered in this work, we observe that the best-fitted values of the normalized Yukawa couplings are about $2σ$ below the corresponding SM ones with the $1σ$ errors of 3%-5%. On the other hand, the gauge-Higgs couplings are consistent with the SM with the $1σ$ errors of 2%-3%. Incidentally, the reduced Yukawa couplings help to explain the excess of the $H\to Zγ$ signal strength of $2.2\pm 0.7$ recently reported by the ATLAS and CMS collaborations.
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Submitted 16 July, 2024; v1 submitted 5 February, 2024;
originally announced February 2024.
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Lifetime of the dark $Z$ boson
Authors:
Dong-Won Jung,
Kang Young Lee,
Chaehyun Yu
Abstract:
The mediator particle between the Standard Model sector and a hidden sector might have a long lifetime to show the observable displaced vertices in experiments. Considering a fermionic dark matter model in which the hidden sector is connected to the Standard Model by an additional Higgs doublet field, the mediator dark $Z$ boson may live long enough. We explore the possibility to observe the displ…
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The mediator particle between the Standard Model sector and a hidden sector might have a long lifetime to show the observable displaced vertices in experiments. Considering a fermionic dark matter model in which the hidden sector is connected to the Standard Model by an additional Higgs doublet field, the mediator dark $Z$ boson may live long enough. We explore the possibility to observe the displaced vertices of the long-lived dark $Z$ boson at the CERN LHC and at the proposed SHiP experiment. We find that the ATLAS and CMS searches for the long-lived dark $Z$ boson can probe the mass range $7 < m_{Z'} < 150~{\rm MeV}$ with 150 fb$^{-1}$ integrated luminosity at the LHC run 3, and the SHiP experiment will probe $2 m_e < m_{Z'} < 15~{\rm MeV}$ range with $6 \times 10^{20}$ protons on target in total 15 years. The dark matter phenomenology is also discussed in the region where such a long-lived mediator is detectable.
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Submitted 3 November, 2023;
originally announced November 2023.
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Cosmic Birefringence by Dark Photon
Authors:
Sung Mook Lee,
Dong Woo Kang,
Jinn-Ouk Gong,
Donghui Jeong,
Dong-Won Jung,
Seong Chan Park
Abstract:
We study the kinetic mixing between the cosmic microwave background (CMB) photon and the birefringent dark photon. These birefringent dark photon may exist in parity-violating dark sector, for example, through the coupling to axion field. We show that the birefringence of the dark photon propagates to the CMB photon, but the resulting birefringence may not be isotropic over the sky, but will be an…
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We study the kinetic mixing between the cosmic microwave background (CMB) photon and the birefringent dark photon. These birefringent dark photon may exist in parity-violating dark sector, for example, through the coupling to axion field. We show that the birefringence of the dark photon propagates to the CMB photon, but the resulting birefringence may not be isotropic over the sky, but will be anisotropic in general. Moreover, our investigation sheds light on the essential role played by kinetic mixing in the generation of two fundamental characteristics of the CMB: circular polarization and spectral distortion.
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Submitted 29 August, 2024; v1 submitted 27 July, 2023;
originally announced July 2023.
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Constraints on the dark Z model from the Higgs boson phenomenology
Authors:
Dong-Won Jung,
Kang Young Lee,
Chaehyun Yu
Abstract:
We study constraints on the hidden sector model mediated by an additional SU(2) Higgs doublet from the phenomenology of Higgs bosons. The hidden sector is assumed to contain a hidden U(1) gauge symmetry and the hidden U(1) gauge boson gets the mass by the electroweak symmetry breaking to be a dark Z boson. The Higgs sector of the model is similar to that of the two Higgs doublet model of type I ex…
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We study constraints on the hidden sector model mediated by an additional SU(2) Higgs doublet from the phenomenology of Higgs bosons. The hidden sector is assumed to contain a hidden U(1) gauge symmetry and the hidden U(1) gauge boson gets the mass by the electroweak symmetry breaking to be a dark Z boson. The Higgs sector of the model is similar to that of the two Higgs doublet model of type I except for the absence of the CP-odd scalar boson. Using the programs of HiggsBounds and HiggsSignals, we incorporate current experimental limits from LEP, Tevatron and LHC to examine the Higgs sector in our model and derive constraints on model parameters. We also discuss the implications of the model on the dark matter phenomenology.
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Submitted 30 May, 2023;
originally announced May 2023.
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On the mass spectrum of heavy Higgs bosons in two-Higgs-doublet model in the light of the CDF $W$-mass anomaly
Authors:
Dong-Won Jung,
Yongtae Heo,
Jae Sik Lee
Abstract:
We analyze the mass spectrum of the charged and neutral Higgs bosons in the framework of two Higgs doublet model (2HDM) in the light of the precision measurement of the $W$ boson mass by the CDF collaboration. We have considered the most general 2HDM potential with explicit CP violation in the Higgs basis which contains the three CP-mixed neutral mass eigenstates $H_1$, $H_2$, and $H_3$ with…
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We analyze the mass spectrum of the charged and neutral Higgs bosons in the framework of two Higgs doublet model (2HDM) in the light of the precision measurement of the $W$ boson mass by the CDF collaboration. We have considered the most general 2HDM potential with explicit CP violation in the Higgs basis which contains the three CP-mixed neutral mass eigenstates $H_1$, $H_2$, and $H_3$ with $M_{H_1}\leq M_{H_2}\leq M_{H_3}$. The high-precision CDF measurement of the $W$ boson mass is characterized by the large positive value of the $T$ parameter. By identifying the lightest neutral Higgs boson $H_1$ as the SM-like one discovered at the LHC, we find that it is necessary to have the mass splitting between the charged Higgs boson $H^\pm$ and the second heaviest neutral one $H_2$ to accommodate the sizable positive deviation of the $T$ parameter from its SM value of $0$. By combining the mass splitting between $H^\pm$ and $H_2$ with the theoretical constraints from the perturbative unitarity and for the Higgs potential to be bounded from below, we implement comprehensive analysis of the mass spectrum of the heavy Higgs bosons taking account of the effects of deviation from the alignment limit and also the mass splitting between $H_3$ and $H_2$. We further analyze the behavior of the heavy-Higgs mass spectrum according to the variation of the $T$ parameter. Finally, concentrating on the heavy mass region $M\equiv (M_{H_2}+M_{H^\pm})/2\gsim 500$ GeV in which we find a mass hierarchy of $M\gg M_{H_1}\sim |Δ| \gsim δ$ with $Δ\equiv M_{H_2}-M_{H^\pm}$ and $δ\equiv M_{H_3}-M_{H_2}$, we discuss some benchmarking scenarios for the searches of heavy Higgs bosons at future colliders such as the high luminosity option of the LHC and a 100 TeV hadron collider.
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Submitted 3 July, 2023; v1 submitted 15 December, 2022;
originally announced December 2022.
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Impact of the CDF $W$-mass anomaly on two Higgs doublet model
Authors:
Yongtae Heo,
Dong-Won Jung,
Jae Sik Lee
Abstract:
We consider the implication of the recent CDF $W$-mass anomaly in the general framework of two Higgs doublet model. We find that the large deviation of the $S$ and $T$ parameters from their SM values of zero leads to the upper limit of about $1$ TeV on the heavy charged and neutral Higgs bosons when it is combined with the theoretical constraints from the perturbative unitarity and for the Higgs p…
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We consider the implication of the recent CDF $W$-mass anomaly in the general framework of two Higgs doublet model. We find that the large deviation of the $S$ and $T$ parameters from their SM values of zero leads to the upper limit of about $1$ TeV on the heavy charged and neutral Higgs bosons when it is combined with the theoretical constraints from the perturbative unitarity and for the Higgs potential to be bounded from below.
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Submitted 1 July, 2022; v1 submitted 12 April, 2022;
originally announced April 2022.
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Positronium Decays with Dark $Z$ and Fermionic Dark Matter
Authors:
Dong-Won Jung,
Chaehyun Yu,
Kang Young Lee
Abstract:
We investigate the invisible decay of positronium to probe the fermionic light dark matter mediated by the dark $Z$ boson. Too tiny is the invisible decay rate of positronium through weak interaction in the standard model to be detected in the experiment. We show that it can be enhanced to be observed in the future if the dark matter is lighter than the electron in the dark $Z$ model. We also comp…
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We investigate the invisible decay of positronium to probe the fermionic light dark matter mediated by the dark $Z$ boson. Too tiny is the invisible decay rate of positronium through weak interaction in the standard model to be detected in the experiment. We show that it can be enhanced to be observed in the future if the dark matter is lighter than the electron in the dark $Z$ model. We also compute the relic abundance of such light dark matter and discuss the Big Bang Nucleosynthesis constraint with an alternative thermal history scenario.
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Submitted 27 November, 2021; v1 submitted 21 November, 2021;
originally announced November 2021.
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Singlet Fermionic Dark Matter with Dark $Z$
Authors:
Dong-Won Jung,
Soo-hyeon Nam,
Chaehyun Yu,
Yeong Gyun Kim,
Kang Young Lee
Abstract:
We present a fermionic dark matter model mediated by the hidden gauge boson. We assume the QED-like hidden sector which consists of a Dirac fermion and U(1)$_X$ gauge symmetry, and introduce an additional scalar electroweak doublet field with the U(1)$_X$ charge as a mediator. The hidden U(1)$_X$ symmetry is spontaneously broken by the electroweak symmetry breaking and there exists a massive extra…
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We present a fermionic dark matter model mediated by the hidden gauge boson. We assume the QED-like hidden sector which consists of a Dirac fermion and U(1)$_X$ gauge symmetry, and introduce an additional scalar electroweak doublet field with the U(1)$_X$ charge as a mediator. The hidden U(1)$_X$ symmetry is spontaneously broken by the electroweak symmetry breaking and there exists a massive extra neutral gauge boson in this model which is the mediator between the hidden and visible sectors. Due to the U(1)$_X$ charge, the additional scalar doublet does not couple to the Standard Model fermions, which leads to the Higgs sector of type I two Higgs doublet model. The new gauge boson couples to the Standard Model fermions with couplings proportional to those of the ordinary $Z$ boson but very suppressed, thus we call it the dark $Z$ boson. We study the phenomenology of the dark $Z$ boson and the Higgs sector, and show the hidden fermion can be the dark matter candidate.
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Submitted 29 April, 2020; v1 submitted 23 February, 2020;
originally announced February 2020.
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Scalar dark matter in the conformally invariant extension of the standard model
Authors:
Dong-Won Jung,
Jungil Lee,
Soo-hyeon Nam
Abstract:
We study a classically scale-invariant model with an electroweak singlet scalar mediator together with a scalar dark matter multiplet of global $O(N)$ symmetry. Our most general conformally invariant scalar potential generates the electroweak symmetry breaking via the Coleman-Weinberg mechanism, and the new scalar singlet acquires its mass through radiative corrections of the SM particles and the…
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We study a classically scale-invariant model with an electroweak singlet scalar mediator together with a scalar dark matter multiplet of global $O(N)$ symmetry. Our most general conformally invariant scalar potential generates the electroweak symmetry breaking via the Coleman-Weinberg mechanism, and the new scalar singlet acquires its mass through radiative corrections of the SM particles and the scalar dark matter. Taking into account the collider bounds, we present the allowed region of new physics parameters satisfying the recent measurement of relic abundance. With the obtained parameter sets, we predict the elastic scattering cross section of the new scalar multiplet into target nuclei for a direct detection of the dark matter. We also perform a full analysis with arbitrary set of parameters for $N \geq 2$, and discuss the implication of the constraints from the on-going direct and indirect detections of dark matter.
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Submitted 11 August, 2019; v1 submitted 23 April, 2019;
originally announced April 2019.
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AdS/QCD approach to the scale-invariant extension of the standard model with a strongly interacting hidden sector
Authors:
Hisaki Hatanaka,
Dong-Won Jung,
Pyungwon Ko
Abstract:
In this paper, we revisit a scale-invariant extension of the standard model (SM) with a strongly interacting hidden sector within AdS/QCD approach. Using the AdS/QCD, we reduce the number of input parameters to three, {\it i.e.} hidden pion decay constant, hidden pion mass and $\tanβ$ that is defined as the ratio of the vacuum expectation values (VEV) of the singlet scalar field and the SM Higgs b…
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In this paper, we revisit a scale-invariant extension of the standard model (SM) with a strongly interacting hidden sector within AdS/QCD approach. Using the AdS/QCD, we reduce the number of input parameters to three, {\it i.e.} hidden pion decay constant, hidden pion mass and $\tanβ$ that is defined as the ratio of the vacuum expectation values (VEV) of the singlet scalar field and the SM Higgs boson. As a result, our model has sharp predictability. We perform the phenomenological analysis of the hidden pions which is one of the dark matter (DM) candidates in this model. With various theoretical and experimental constraints we search for the allowed parameter space and find that both resonance and non-resonance solutions are possible. Some typical correlations among various observables such as thermal relic density of hidden pions, Higgs boson signal strengths and DM-nucleon cross section are investigated. We provide some benchmark points for experimental tests.
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Submitted 19 August, 2016; v1 submitted 9 June, 2016;
originally announced June 2016.
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Higgs-dilaton(radion) system confronting the LHC Higgs data
Authors:
Dong-Won Jung,
P. Ko
Abstract:
We consider the Higgs-dilaton(radion) system using the trace of energy-momentum tensor ($T_{~μ}^μ$) with the full Standard Model (SM) gauge symmetry $G_{\rm SM} \equiv SU(3)_c \times SU(2)_L \times U(1)_Y$, and find out that the resulting phenomenology for the Higgs-dilaton(radion) system is distinctly different from the earlier studies based on the $T_{~μ}^μ$ with the unbroken subgroup…
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We consider the Higgs-dilaton(radion) system using the trace of energy-momentum tensor ($T_{~μ}^μ$) with the full Standard Model (SM) gauge symmetry $G_{\rm SM} \equiv SU(3)_c \times SU(2)_L \times U(1)_Y$, and find out that the resulting phenomenology for the Higgs-dilaton(radion) system is distinctly different from the earlier studies based on the $T_{~μ}^μ$ with the unbroken subgroup $H_{\rm SM} \equiv SU(3)_c \times U(1)_{\rm em}$ of $G_{\rm SM}$. After electroweak symmetry breaking (EWSB), the SM Higgs boson and dilaton(radion) will mix with each other, and there appear two Higgs-like scalar bosons and the Higgs-dilaton mixing changes the scalar phenomenology in interesting ways. The signal strengths for the $gg$-initiated channels could be modified significantly compared with the SM predictions due to the QCD scale anomaly and the Higgs-dilaton(radion) mixing, whereas anomaly contributions are almost negligible for other channels. We also discuss the self-couplings and the signal strengths of the $126$ GeV scalar boson in various channels and possible constraints from the extra light/heavy scalar boson. The Higgs-dilaton(radion) system considered in this work has a number of distinctive features that could be tested by the upcoming LHC running and at the ILC.
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Submitted 21 April, 2014; v1 submitted 22 January, 2014;
originally announced January 2014.
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Mass and rapidity dependent top quark forward-backward asymmetry in the effective Lagrangian approach
Authors:
Dong-Won Jung,
P. Ko,
Jae Sik Lee
Abstract:
We study the invariant mass and rapidity dependent top quark forward-backward asymmetry from the effective Lagrangian viewpoint. The Wilson coefficients are constrained by the experimental observations and the concrete models that reproduce the low energy effective Lagaragians are considered. Some of them are disfavored and others relatively favored. For each cases, we estimate the appropriacy of…
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We study the invariant mass and rapidity dependent top quark forward-backward asymmetry from the effective Lagrangian viewpoint. The Wilson coefficients are constrained by the experimental observations and the concrete models that reproduce the low energy effective Lagaragians are considered. Some of them are disfavored and others relatively favored. For each cases, we estimate the appropriacy of the effective Lagrangian approach.
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Submitted 6 March, 2013;
originally announced March 2013.
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Majorana versus Dirac mass from holomorphic supersymmetric Nambu-Jona-Lasinio Model
Authors:
Yan-Min Dai,
Gaber Faisel,
Dong-Won Jung,
Otto C. W. Kong
Abstract:
We study the theoretical features in relation to dynamical mass generation and symmetry breaking for the recently proposed holomorphic supersymmetric Nambu--Jona-Lasinio model. The basic model has two different chiral superfields (multiplets) with a strongly coupled dimension five four-superfield interaction. In addition to the possibility of generation of Dirac mass between the pair established e…
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We study the theoretical features in relation to dynamical mass generation and symmetry breaking for the recently proposed holomorphic supersymmetric Nambu--Jona-Lasinio model. The basic model has two different chiral superfields (multiplets) with a strongly coupled dimension five four-superfield interaction. In addition to the possibility of generation of Dirac mass between the pair established earlier, we show here the new option of generation of Majorana masses for each chiral superfield. We also give a first look at what condition may prefer Dirac over Majorana mass, illustrating that a split in the soft supersymmetry breaking masses is crucial. In particular, in the limit where one of the soft masses vanish, we show that generation of the Majorana mass is no longer an option, while the Dirac mass generation survives well. The latter is sensitive mostly to the average of the two soft masses. The result has positive implication on the application of the model framework towards dynamical electroweak symmetry breaking with Higgs superfields as composites.
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Submitted 29 March, 2013; v1 submitted 5 August, 2012;
originally announced August 2012.
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Dynamical Symmetry Breaking in Supersymmetric Extensions of Nambu-Jona-Lasinio Model
Authors:
Gaber Faisel,
Dong-Won Jung,
Otto C. W. Kong
Abstract:
In this paper we discuss Nambu-Jona-Lasinio model as a classical model for dynamical mass generation and symmetry breaking. In addition we discuss the possible supersymmetric extensions of this model resulting from interaction terms with four chiral superfields that may be regarded as a supersymmetric generalization of the four-fermion interactions of the Nambu-Jona-Lasinio model. A four-superfiel…
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In this paper we discuss Nambu-Jona-Lasinio model as a classical model for dynamical mass generation and symmetry breaking. In addition we discuss the possible supersymmetric extensions of this model resulting from interaction terms with four chiral superfields that may be regarded as a supersymmetric generalization of the four-fermion interactions of the Nambu-Jona-Lasinio model. A four-superfield interaction terms can be constructed as either dimension 6 or dimension 5 operators. Through analyzing solutions to the gap equations, we discuss the dynamical generation of superfield Dirac mass, including a supersymmetry breaking part. A dynamical symmetry breaking generally goes along with the dynamical mass generation, for which a bi-superfield condensate is responsible.
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Submitted 27 August, 2012; v1 submitted 25 January, 2012;
originally announced January 2012.
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Mass dependent top forward backward asymmetry in the effective Lagrangian approach: Addendum to "Model independent analysis of the forward-backward asymmetry of top quark production at the Tevatron"
Authors:
Dong-Won Jung,
P. Ko,
Jae Sik Lee
Abstract:
Recently the CDF and the D0 Collaborations presented the data on the top forward-backward (FB) asymmetry A_FB as functions of M_(t t^bar) and Δy = y_t - y_t^bar. We study these observables in the effective Lagrangian approach with dimension-6 q q^bar t t^bar contact interactions, and compare with the CDF and D0 data. When we stay within the validity region of the effective Lagrangian approach, the…
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Recently the CDF and the D0 Collaborations presented the data on the top forward-backward (FB) asymmetry A_FB as functions of M_(t t^bar) and Δy = y_t - y_t^bar. We study these observables in the effective Lagrangian approach with dimension-6 q q^bar t t^bar contact interactions, and compare with the CDF and D0 data. When we stay within the validity region of the effective Lagrangian approach, the mass dependent top FB asymmetry turns out to be smaller than the CDF data, more than 2-sigma away. If this discrepancy remains in the future data with better statistics, it would imply that the effective Lagrangian approach is not adequate for the top FB asymmetry, and a new physics scale around a few hundred GeV in the t- or u-channel may be responsible for the observed top FB asymmetry.
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Submitted 18 January, 2012; v1 submitted 14 November, 2011;
originally announced November 2011.
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Dynamical Symmetry Breaking with Four-Superfield Interactions
Authors:
Gaber Faisel,
Dong-Won Jung,
Otto C. W. Kong
Abstract:
We investigate the dynamical mass generation resulted from interaction terms with four chiral superfields. The kind of interactions maybe considered a supersymmetric generalization of the four-fermion interactions of the classic Nambu--Jona-Lasinio model. A four-superfield interaction that contains a four-fermion interaction as one of its component terms has been the standard supersymmetrization o…
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We investigate the dynamical mass generation resulted from interaction terms with four chiral superfields. The kind of interactions maybe considered a supersymmetric generalization of the four-fermion interactions of the classic Nambu--Jona-Lasinio model. A four-superfield interaction that contains a four-fermion interaction as one of its component terms has been the standard supersymmetrization of the NJL model for decades. Recently, we introduced a holomorphic variant with a dimension five interaction term instead. The latter is a main target of the present analysis. With the introduction of a new perspective on the superfield gap equation, we derive it for each one of the four-superfield interactions, using the supergraph technique. Through analyzing solutions to the gap equations, we illustrate the dynamical generation of superfield Dirac mass, including a supersymmetry breaking part. A dynamical symmetry breaking generally goes along with the dynamical mass generation, for which a bi-superfield condensate is responsible. The explicit illustration of dynamical symmetry breaking from the holomorphic dimension five interaction is reported for the first time. It has rich and novel features, which would be easily missed without the superfield approach developed here. We also discuss the nature of the bi-superfield condensate and its role of the effective Higgs superfield picture for both cases, illustrating their difference. Note that such a holomorphic quark superfield interaction term can successful account for the electroweak symmetry breaking with Higgs superfields as composites.
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Submitted 21 February, 2012; v1 submitted 31 July, 2011;
originally announced August 2011.
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Possible Common Origin of the Top Forward-backward Asymmetry and the CDF Dijet Resonance
Authors:
Dong-Won Jung,
P. Ko,
Jae Sik Lee
Abstract:
A color-singlet neutral vector boson is considered as a possible common origin of the top forward-backward asymmetry and the CDF dijet resonance. We identify chiral and flavor structures of the couplings of this new vector boson to the standard model quarks for which one could accommodate both data. We also demonstrate that non-vanishing observables involving longitudinal top polarizations can pro…
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A color-singlet neutral vector boson is considered as a possible common origin of the top forward-backward asymmetry and the CDF dijet resonance. We identify chiral and flavor structures of the couplings of this new vector boson to the standard model quarks for which one could accommodate both data. We also demonstrate that non-vanishing observables involving longitudinal top polarizations can provide useful criteria for the possible existence of parity violating new physics in the q q^bar -> t t^bar process, and discrimination between the flavor-conserving and flavor-violating cases.
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Submitted 14 September, 2011; v1 submitted 22 April, 2011;
originally announced April 2011.
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Model-independent analysis of forward-backward asymmetry of top quark production at the Tevatron
Authors:
Dong-won Jung,
P. Ko,
Jae Sik Lee,
Soo-hyeon Nam
Abstract:
We perform a model independent analysis on $q \bar{q} \rightarrow t \bar{t}$ using an effective lagrangian with dim-6 four-quark operators, and derive necessary conditions on new physics that are consistent with the $t\bar{t}$ production cross section %($σ_{t\bar{t}}$) and and the forward-backward (FB) asymmetry ($A_{\rm FB}$) measured at the Tevatron. We also propose a new FB spin-spin correlatio…
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We perform a model independent analysis on $q \bar{q} \rightarrow t \bar{t}$ using an effective lagrangian with dim-6 four-quark operators, and derive necessary conditions on new physics that are consistent with the $t\bar{t}$ production cross section %($σ_{t\bar{t}}$) and and the forward-backward (FB) asymmetry ($A_{\rm FB}$) measured at the Tevatron. We also propose a new FB spin-spin correlation that is strongly correlated with the $A_{\rm FB}$, and discuss possible new physics scenarios that could generate such dim-6 operators.
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Submitted 1 December, 2010;
originally announced December 2010.
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Longitudinal top polarization as a probe of a possible origin of forward-backward asymmetry of the top quark at the Tevatron
Authors:
Dong-Won Jung,
P. Ko,
Jae Sik Lee
Abstract:
If the forward-backward (FB) asymmetry of top quark ($A_{\rm FB}$) observed at the Tevatron deviates from the SM prediction, there must be $P$-violating interactions in $q\bar{q} \rightarrow t\bar{t}$. This new interaction will necessarily affect the top spin polarization. In this letter, we perform a model independent analysis on the longitudinal (anti)top polarization ($P_L$ and $\bar{P}_L$) usi…
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If the forward-backward (FB) asymmetry of top quark ($A_{\rm FB}$) observed at the Tevatron deviates from the SM prediction, there must be $P$-violating interactions in $q\bar{q} \rightarrow t\bar{t}$. This new interaction will necessarily affect the top spin polarization. In this letter, we perform a model independent analysis on the longitudinal (anti)top polarization ($P_L$ and $\bar{P}_L$) using an effective lagrangian with dim-6 four-quark operators relevant for $q \bar{q} \rightarrow t \bar{t}$, and show that the $P$-odd observable corresponding to the polarization difference $(P_L - \bar{P}_L)$ gives important informations on the chiral structures of new physics that might be relevant to the $A_{\rm FB}$.
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Submitted 24 May, 2011; v1 submitted 27 November, 2010;
originally announced November 2010.
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Model independent analysis of the forward-backward asymmetry of top quark production at the Tevatron
Authors:
Dong-Won Jung,
P. Ko,
Jae Sik Lee,
Soo-hyeon Nam
Abstract:
Motivated by a possible anomaly in the forward-backward (FB) asymmetry of top quark (A_{\rm FB}) observed at the Tevatron, we perform a model independent analysis on q \bar{q} \to t \bar{t} using an effective lagrangian with dim-6 four-quark operators. We derive necessary conditions on new physics structures and the couplings that are consistent with the t\bar{t} production cross section and A_{\r…
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Motivated by a possible anomaly in the forward-backward (FB) asymmetry of top quark (A_{\rm FB}) observed at the Tevatron, we perform a model independent analysis on q \bar{q} \to t \bar{t} using an effective lagrangian with dim-6 four-quark operators. We derive necessary conditions on new physics structures and the couplings that are consistent with the t\bar{t} production cross section and A_{\rm FB} measured at the Tevatron, and discuss possible new physics scenarios that could generate such dim-6 operators.
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Submitted 28 June, 2010; v1 submitted 7 December, 2009;
originally announced December 2009.
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AMSB Demystified
Authors:
Dong-Won Jung,
Jae Yong Lee
Abstract:
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 breakd…
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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 a spurion in gauge-mediated supersymmetry breaking scenario.
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Submitted 29 September, 2009;
originally announced September 2009.
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Holomorphic Supersymmetric Nambu--Jona-Lasinio Model with Application to Electroweak Symmetry Breaking
Authors:
D. -W. Jung,
O. C. W. Kong,
J. S. Lee
Abstract:
Based on our idea of an alternative supersymmetrization of the Nambu--Jona-Lasinio model for dynamical symmetry breaking, we analyze the resulted new model with a holomorphic dimension-five operator in the superpotential. The approach provides a new direction for modeling dynamical symmetry breaking in a supersymmetric setting. In particular, we adopt the idea to formulate a model that gives ris…
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Based on our idea of an alternative supersymmetrization of the Nambu--Jona-Lasinio model for dynamical symmetry breaking, we analyze the resulted new model with a holomorphic dimension-five operator in the superpotential. The approach provides a new direction for modeling dynamical symmetry breaking in a supersymmetric setting. In particular, we adopt the idea to formulate a model that gives rise to the Minimal Supersymmetric Standard Model as the low energy effective theory with both Higgs superfields as composites. A renormalization group analysis is performed to establish the phenomenological viability of the scenario, with admissible background scale that could go down to the TeV scale. We give the Higgs mass range predicted.
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Submitted 8 February, 2010; v1 submitted 19 June, 2009;
originally announced June 2009.
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Anomaly-Mediated Supersymmetry Breaking Demystified
Authors:
Dong-Won Jung,
Jae Yong Lee
Abstract:
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 breakd…
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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 a spurion in gauge-mediated supersymmetry breaking scenario.
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Submitted 18 February, 2009; v1 submitted 3 February, 2009;
originally announced February 2009.
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Production of the charged Higgs bosons at the CERN Large Hadron Collider in the left-right symmetric model
Authors:
Dong-Won Jung,
Kang Young Lee
Abstract:
We study the production of the charged Higgs boson at the LHC in the left-right symmetric model. It is shown that there exists a lower bound of the cross section. We investigate that predicted cross sections of this model are generally larger than those of the two Higgs doublet model or the minimal supersymmetric model.
We study the production of the charged Higgs boson at the LHC in the left-right symmetric model. It is shown that there exists a lower bound of the cross section. We investigate that predicted cross sections of this model are generally larger than those of the two Higgs doublet model or the minimal supersymmetric model.
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Submitted 30 June, 2008; v1 submitted 12 February, 2008;
originally announced February 2008.
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1-loop Corrections to the ρParameter in the Left-Right Twin Higgs Model
Authors:
Dong-Won Jung,
Jae Yong Lee
Abstract:
We implement a one-loop analysis of the $ρ$ parameter in the Left Right Twin Higgs model, including the logarithmically enhanced contributions from both fermion and scalar loops. Numerical results show that the one-loop contributions are dominant over the tree level corrections in most regions of parameter space. The experimentally allowed values of $ρ$-parameter divide the allowed parameter spa…
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We implement a one-loop analysis of the $ρ$ parameter in the Left Right Twin Higgs model, including the logarithmically enhanced contributions from both fermion and scalar loops. Numerical results show that the one-loop contributions are dominant over the tree level corrections in most regions of parameter space. The experimentally allowed values of $ρ$-parameter divide the allowed parameter space into two regions; less than $670 {\rm GeV}$ and larger than $1100 {\rm GeV}$ roughly, for symmetry breaking scale $f$. Our numerical analysis significantly reduces the parameter space which are favorably accessible to the LHC.
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Submitted 15 October, 2007; v1 submitted 13 October, 2007;
originally announced October 2007.
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Electroweak symmetry breaking and cold dark matter from strongly interacting hidden sector
Authors:
Taeil Hur,
Dong-Won Jung,
P. Ko,
Jae Yong Lee
Abstract:
We consider a hidden sector with a vectorlike confining gauge theory like QCD with $N_{h,c}$ colors and $N_{h,f}$ light quarks ${\cal Q}_h$ in the hidden sector. Then a scale $Λ_H$ would be generated by dimensional transmutation, and chiral symmetry breaking occurs in the hidden sector. This scale $Λ_H$ can play a role of the SM Higgs mass parameter, triggering electroweak symmetry breaking (EWSB)…
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We consider a hidden sector with a vectorlike confining gauge theory like QCD with $N_{h,c}$ colors and $N_{h,f}$ light quarks ${\cal Q}_h$ in the hidden sector. Then a scale $Λ_H$ would be generated by dimensional transmutation, and chiral symmetry breaking occurs in the hidden sector. This scale $Λ_H$ can play a role of the SM Higgs mass parameter, triggering electroweak symmetry breaking (EWSB). Furthermore the lightest mesons in the hidden sector is stable by flavor conservation of the hidden sector strong interaction, and could be a good cold dark matter (CDM). We study collider phenomenology, and relic density and direct detection rates of the CDM of this model.
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Submitted 1 January, 2011; v1 submitted 8 September, 2007;
originally announced September 2007.
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Exploring the charged Higgs bosons in the lef-right symmetric model
Authors:
Dong-Won Jung,
Kang Young Lee
Abstract:
We explore constraints on the charged Higgs sector in the left-right (LR) model from the present experimental data. Due to the different Yukawa structure, the allowed parameter space of the charged Higgs boson in the LR model is different from that in the two Higgs doublet model. We find that the constraint from $t \to b H^\pm$ decay at Tevatron is most significant, while $B \to τν$ decay could…
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We explore constraints on the charged Higgs sector in the left-right (LR) model from the present experimental data. Due to the different Yukawa structure, the allowed parameter space of the charged Higgs boson in the LR model is different from that in the two Higgs doublet model. We find that the constraint from $t \to b H^\pm$ decay at Tevatron is most significant, while $B \to τν$ decay could provide no constraint on the LR model. Bounds from $e^- e^+ \to H^- H^+$ process at LEP are similar to that in the two Higgs doublet model.
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Submitted 13 May, 2008; v1 submitted 11 January, 2007;
originally announced January 2007.
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One-loop Radiative Corrections to the $ρ$ Parameter in the Left Right Twin Higgs Model
Authors:
Dong-Won Jung,
Jae Yong Lee
Abstract:
We implement a one-loop analysis of the $ρ$ parameter in the Left Right Twin Higgs model, including the logarithmically enhanced contributions from both heavy fermion and scalar loops. Numerical analysis indicates that the one-loop corrections are dominant over the tree-level contributions in most regions of parameter space. The experimentally allowed values of the $ρ$-parameter divide the allowed…
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We implement a one-loop analysis of the $ρ$ parameter in the Left Right Twin Higgs model, including the logarithmically enhanced contributions from both heavy fermion and scalar loops. Numerical analysis indicates that the one-loop corrections are dominant over the tree-level contributions in most regions of parameter space. The experimentally allowed values of the $ρ$-parameter divide the allowed parameter space into two regions; less than $670 {\rm GeV}$ and larger than $1100 {\rm GeV}$ roughly, for the symmetry breaking scale $f$. Therefore our result significantly reduces the parameter space which are favorably accessible to the LHC.
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Submitted 2 May, 2013; v1 submitted 10 January, 2007;
originally announced January 2007.
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Partially composite 2-Higgs-doublet model
Authors:
Dong-Won Jung
Abstract:
In the extra dimensional scenarios with gauge fields in the bulk, the Kaluza-Klein (KK) gauge bosons can induce Nambu-Jona-Lasinio (NJL) type attractive four-fermion interactions, which can break electroweak symmetry dynamically with accompanying composite Higgs fields. We consider a possibility that electroweak symmetry breaking (EWSB) is triggered by both a fundamental Higgs and a composite Hi…
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In the extra dimensional scenarios with gauge fields in the bulk, the Kaluza-Klein (KK) gauge bosons can induce Nambu-Jona-Lasinio (NJL) type attractive four-fermion interactions, which can break electroweak symmetry dynamically with accompanying composite Higgs fields. We consider a possibility that electroweak symmetry breaking (EWSB) is triggered by both a fundamental Higgs and a composite Higgs arising in a dynamical symmetry breaking mechanism induced by a new strong dynamics. The resulting Higgs sector is a partially composite two-Higgs doublet model with specific boundary conditions on the coupling and mass parameters originating at a compositeness scale $Λ$. The phenomenology of this model is discussed including the collider phenomenology at LHC and ILC.
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Submitted 12 September, 2006; v1 submitted 10 August, 2006;
originally announced August 2006.
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Partially composite two-Higgs doublet model
Authors:
Byungchul Chung,
Kang Young Lee,
Dong-Won Jung,
Pyungwon Ko
Abstract:
In the extra dimensional scenarios with gauge fields in the bulk, the Kaluza-Klein (KK) gauge bosons can induce Nambu-Jona-Lasinio (NJL) type attractive four-fermion interactions, which can break electroweak symmetry dynamically with accompanying composite Higgs fields. We consider a possibility that electroweak symmetry breaking (EWSB) is triggered by both a fundamental Higgs and a composite Hi…
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In the extra dimensional scenarios with gauge fields in the bulk, the Kaluza-Klein (KK) gauge bosons can induce Nambu-Jona-Lasinio (NJL) type attractive four-fermion interactions, which can break electroweak symmetry dynamically with accompanying composite Higgs fields. We consider a possibility that electroweak symmetry breaking (EWSB) is triggered by both a fundamental Higgs and a composite Higgs arising in a dynamical symmetry breaking mechanism induced by a new strong dynamics. The resulting Higgs sector is a partially composite two-Higgs doublet model with specific boundary conditions on the coupling and mass parameters originating at a compositeness scale $Λ$. The phenomenology of this model is discussed including the collider phenomenology at LHC and ILC.
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Submitted 22 December, 2005; v1 submitted 6 October, 2005;
originally announced October 2005.
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Neutrino Oscillations and Collider Test of the R-parity Violating mSUGRA Model
Authors:
Dong-Won Jung
Abstract:
We study the R-parity violating minimal supergravity models accounting for the observed neutrino masses and mixing, which can be tested in future collider experiments. The bi-large mixing can be explained by allowing five dominant tri-linear couplings $ λ'_{1,2,3}$ and $λ_{1,2}$. The desired ratio of the atmospheric and solar neutrino mass-squared differences can be obtained in a very limited pa…
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We study the R-parity violating minimal supergravity models accounting for the observed neutrino masses and mixing, which can be tested in future collider experiments. The bi-large mixing can be explained by allowing five dominant tri-linear couplings $ λ'_{1,2,3}$ and $λ_{1,2}$. The desired ratio of the atmospheric and solar neutrino mass-squared differences can be obtained in a very limited parameter space where the tree-level contribution is tuned to be suppressed. In this allowed region, we quantify the correlation between the three neutrino mixing angles and the tri-linear R-parity violating couplings. Such a prediction on the couplings can be tested in the next linear colliders by observing the branching ratios of the lightest supersymmetric particle (LSP). For the stau or the neutralino LSP, the ratio $|λ_1|^2: |λ_2|^2: |λ_1|^2 + |λ_2|^2$ can be measured by establishing $Br(eν): Br(μν) : Br(τν)$ or $Br(νe^\pm τ^\mp): Br(νμ^\pmτ^\mp) : Br(ντ^\pmτ^\mp)$, respectively. The information on the couplings $λ'_i$ can be drawn by measuring $Br(l_i t \bar{b}) \propto |λ'_i|^2$ if the neutralino LSP is heavier than the top quark.
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Submitted 15 September, 2004;
originally announced September 2004.
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Neutrino Oscillations and Collider Test of the R-parity Violating Minimal Supergravity Model
Authors:
Dong-Won Jung,
Sin Kyu Kang,
Jong Dae Park,
Eung Jin Chun
Abstract:
We study the R-parity violating minimal supergravity models accounting for the observed neutrino masses and mixing, which can be tested in future collider experiments. The bi-large mixing can be explained by allowing five dominant tri-linear couplings $ λ'_{1,2,3}$ and $λ_{1,2}$. The desired ratio of the atmospheric and solar neutrino mass-squared differences can be obtained in a very limited pa…
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We study the R-parity violating minimal supergravity models accounting for the observed neutrino masses and mixing, which can be tested in future collider experiments. The bi-large mixing can be explained by allowing five dominant tri-linear couplings $ λ'_{1,2,3}$ and $λ_{1,2}$. The desired ratio of the atmospheric and solar neutrino mass-squared differences can be obtained in a very limited parameter space where the tree-level contribution is tuned to be suppressed. In this allowed region, we quantify the correlation between the three neutrino mixing angles and the tri-linear R-parity violating couplings. Qualitatively, the relations $| λ'_1 | < | λ'_2| \sim | λ'_3|$, and $|λ_1| \sim |λ_2|$ are required by the large atmospheric neutrino mixing angle $θ_{23}$ and the small angle $θ_{13}$, and the large solar neutrino mixing angle $θ_{12}$, respectively. Such a prediction on the couplings can be tested in the next linear colliders by observing the branching ratios of the lightest supersymmetric particle (LSP). For the stau or the neutralino LSP, the ratio $|λ_1|^2: |λ_2|^2: |λ_1|^2 + |λ_2|^2$ can be measured by establishing $Br(eν): Br(μν) : Br(τν)$ or $Br(νe^\pm τ^\mp ): Br(νμ^\pmτ^\mp) : Br(ντ^\pmτ^\mp)$, respectively. The information on the couplings $λ'_i$ can be drawn by measuring $Br(l_i t \bar{b}) \propto |λ'_i|^2$ if the neutralino LSP is heavier than the top quark.
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Submitted 8 July, 2004;
originally announced July 2004.
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Neutrino Mass Matrix in the Minimal Supergravity Model: Bi-large Mixing with Trilinear R-parity Violation
Authors:
Eung Jin Chun,
Dong-Won Jung,
Sin Kyu Kang,
Jong Dae Park
Abstract:
We study the correlation between the neutrino oscillation and the production/decay of the lightest supersymmetric particle(LSP) in the context of the minimal supergravity model(mSUGRA) without R-parity. We show how the neutrino masses and mixing which are consistent with the recent neutrino data can be obtained in this model, and describe how to probe the model by observing the LSP decay at coll…
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We study the correlation between the neutrino oscillation and the production/decay of the lightest supersymmetric particle(LSP) in the context of the minimal supergravity model(mSUGRA) without R-parity. We show how the neutrino masses and mixing which are consistent with the recent neutrino data can be obtained in this model, and describe how to probe the model by observing the LSP decay at collider experiments. It is shown that the generic 1-loop contributions to neutrino masses are too small to account for the solar and atmospheric neutrino oscillations and thus some fine cancellation in tree-level contribution is required to severely constrain the viable parameter space. In most parameter space of mSUGRA, the neutralino or the stau is LSP. Examining both cases, we find that there is a simple correlation between the neutrino mixing angles and the LSP branching ratios in the small $\tanβ$ region so that the model can be clearly tested in the future colliders. In the large $\tanβ$ region, such a correlation is obscured by the large tau Yukawa contribution which makes it nontrivial to test the model.
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Submitted 23 December, 2003;
originally announced December 2003.
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Neutrino Masses, Baryogenesis and Bilinear R-parity Violation
Authors:
A. G. Akeroyd,
E. J. Chun,
M. A. Diaz,
D. -W. Jung
Abstract:
We consider the impact of cosmological $B-L$ constraints on supersymmetric standard models with bilinear breaking of R-parity. In order to avoid erasing any primordial baryon or lepton asymmetry above the electroweak scale, $B-L$ violation for at least one generation should be sufficiently small. Working in the context of models with non--universal soft supersymmetry breaking masses, we show how…
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We consider the impact of cosmological $B-L$ constraints on supersymmetric standard models with bilinear breaking of R-parity. In order to avoid erasing any primordial baryon or lepton asymmetry above the electroweak scale, $B-L$ violation for at least one generation should be sufficiently small. Working in the context of models with non--universal soft supersymmetry breaking masses, we show how the above cosmological constraint can be satisfied while simultaneously providing a neutrino mass matrix required by current data.
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Submitted 31 July, 2003;
originally announced July 2003.
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CP violation in associated charged Higgs boson production with a single top at the LHC
Authors:
Kang Young Lee,
Dong-Won Jung,
H. S. Song
Abstract:
We explore the CP violation in the charged Higgs production associated with a top quark at the LHC in the MSSM. The supersymmetric phases of gaugino masses and trilinear $A$ terms lead to a CP violating asymmetry of the cross section in the $ p p \to g b \to t H^\pm$ process through loop corrections to the $tbH^\pm$ vertex. We find that a CP violation more than 10 % is possible if the charged Hi…
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We explore the CP violation in the charged Higgs production associated with a top quark at the LHC in the MSSM. The supersymmetric phases of gaugino masses and trilinear $A$ terms lead to a CP violating asymmetry of the cross section in the $ p p \to g b \to t H^\pm$ process through loop corrections to the $tbH^\pm$ vertex. We find that a CP violation more than 10 % is possible if the charged Higgs boson is heavy enough.
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Submitted 26 October, 2004; v1 submitted 19 July, 2003;
originally announced July 2003.
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Bi-large neutrino mixing from bilinear R-parity violation with non-universality
Authors:
E. J Chun,
D. -W. Jung,
J. D Park
Abstract:
We investigate how the bi-large mixing required by the recent neutrino data can be accommodated in the supersymmetric standard model allowing bilinear R-parity violation and non-universal soft terms. In this scheme, the tree-level contribution and the so-called Grossman-Haber one-loop diagrams are two major sources of the neutrino mass matrix. The relative size of these two contributions falls i…
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We investigate how the bi-large mixing required by the recent neutrino data can be accommodated in the supersymmetric standard model allowing bilinear R-parity violation and non-universal soft terms. In this scheme, the tree-level contribution and the so-called Grossman-Haber one-loop diagrams are two major sources of the neutrino mass matrix. The relative size of these two contributions falls into the right range to generate the atmospheric and solar neutrino mass hierarchy. On the other hand, the bi-large mixing is typically obtained by a mild tuning of input parameters to arrange a partial cancellation among various contributions.
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Submitted 20 November, 2002;
originally announced November 2002.
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Collider Signatures of Neutrino Masses and Mixing from R-parity Violation
Authors:
E. J. Chun,
D. W. Jung,
S. K. Kang,
J. D. Park
Abstract:
R-parity violation in the supersymmetric standard model can be the source of neutrino masses and mixing. We analyze the neutrino mass matrix coming from either bilinear or trilinear R-parity violation and its collider signatures, assuming that the atmospheric and solar neutrino data are explained by three active neutrino oscillations. Taking the gauge mediated supersymmetry breaking mechanism, w…
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R-parity violation in the supersymmetric standard model can be the source of neutrino masses and mixing. We analyze the neutrino mass matrix coming from either bilinear or trilinear R-parity violation and its collider signatures, assuming that the atmospheric and solar neutrino data are explained by three active neutrino oscillations. Taking the gauge mediated supersymmetry breaking mechanism, we show that the lightest neutralino decays well inside the detector and the model could be tested by observing its branching ratios in the future colliders. In the bilinear model where only the small solar neutrino mixing angle can be accommodated, the relation, $10^3$ BR($νe^\pm τ^\mp$) $\sim$ BR($νμ^\pm τ^\mp$) $\approx$ BR($ντ^\pm τ^\mp$), serves as a robust test of the model. The large mixing angle solution can be realized in the trilinear model which predicts BR($νe^\pm τ^\mp$) $\sim$ BR($νμ^\pm τ^\mp$) $\sim$ BR($ντ^\pm τ^\mp$). In either case, the relation, BR($e jj$) $\ll$ BR($μjj$) $\sim$ BR($τjj$), should hold to be consistent with the atmospheric neutrino and CHOOZ experiments.
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Submitted 4 June, 2002;
originally announced June 2002.
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Polarization effects on W boson pair productions with the extra neutral gauge boson at the e^+ e^- Linear Collider
Authors:
Dong-Won Jung,
Kang Young Lee,
H. S. Song,
Chaehyun Yu
Abstract:
We perform the comprehensive analysis of the polarization effects on the e^+e^- -> W^+W^- process in the presence of the extra neutral gauge boson at the LC energies. Consideration of the polarizations of the produced W bosons and the beam polarizations provides substantial enhancements of the sensitivity to the Z-Z' mixing angles in various models and the asymmetry variables also give the stric…
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We perform the comprehensive analysis of the polarization effects on the e^+e^- -> W^+W^- process in the presence of the extra neutral gauge boson at the LC energies. Consideration of the polarizations of the produced W bosons and the beam polarizations provides substantial enhancements of the sensitivity to the Z-Z' mixing angles in various models and the asymmetry variables also give the strict constraints on the mixing angles. We find that the χ-model and the left-right model get the strict constraint from σ_{LL}^{unpol} while the ψ-model and the η-model from the beam polarization asymmetry.
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Submitted 15 May, 1999;
originally announced May 1999.