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Volume 116, Issue 1
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Article type: Cover
2008 Volume 116 Issue 1 Pages Cover1-
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
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Article type: Appendix
2008 Volume 116 Issue 1 Pages App1-
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
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Article type: Appendix
2008 Volume 116 Issue 1 Pages A1-A2
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
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Maxim PospelovArticle type: Article
2008 Volume 116 Issue 1 Pages A3-A16
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSParticle physics beyond Standard Model is the most likely source of dark matter seen in the Universe on many different scales. In these two lectures I summarize some recent developments, covering the minimal model of WIMPs, WIMP signal in B-physics, and the Catalyzed Big Bang Nucleosynthesis.View full abstractDownload PDF (1198K) -
Ryuichiro KitanoArticle type: Article
2008 Volume 116 Issue 1 Pages A17-A28
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSIt has been more than twenty years since theorists started discussing supersymmetric model building/phenomenology. I review mechanisms of supersymmetry breaking/mediation and problems in each scenario. I propose a simple model to address those problems and discuss its phenomenology.View full abstractDownload PDF (828K) -
Guido AltarelliArticle type: Article
2008 Volume 116 Issue 1 Pages A29-A55
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSWe present a concise review of models for neutrino masses and mixings with particular emphasis on recent developments and current problems. We discuss in detail attempts at reproducing approximate tri-bimaximal mixing starting from discrete symmetry groups, notably A4. We discuss the problems encountered when trying to extend the symmetry to the quark sector and to construct Grand Unified versions.View full abstractDownload PDF (2093K) -
Michael RatzArticle type: Article
2008 Volume 116 Issue 1 Pages A56-A76
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSGrand unified models in four dimensions typically suffer from the doublet-triplet splitting problem. This obstacle can be overcome in higher-dimensional settings, where a non-trivial gauge group topography can explain the simultaneous appearance of complete standard model generations in the form of 16-plets of SO(10) and the Higgs fields as split multiplets. In these notes, the emerging scheme of 'local grand unification' and its realization in the context of orbifold compactifications of the heterotic string are reviewed.View full abstractDownload PDF (1568K) -
Yeong Gyun KimArticle type: Article
2008 Volume 116 Issue 1 Pages A77-A102
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSWe consider a few selected topics on SUSY phenomenology at the LHC. The signatures of mirage mediation at the LHC is discussed. The 7 polarization effects on SUSY cascade decay is presented. A new collider observable 'gluino m_<T2>' is introduced and its physical property is investigated.View full abstractDownload PDF (1834K) -
Hisaki HatanakaArticle type: Article
2008 Volume 116 Issue 1 Pages A103-A105
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSIn B → VV(V is a vector meson) decay, a polarization anomaly is observed. In this talk, we consider b → ss^^-s-four quark scalar operators which could be induced by new physics, and seek the possibility to explain the B→φK^* and B→Kη(′) simultaneously.View full abstractDownload PDF (224K) -
S.-G. Kim, N. Maekawa, A Matsuzaki, K. Sakurai, T. YoshikawaArticle type: Article
2008 Volume 116 Issue 1 Pages A106-A108
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSWe discuss the interesting feature of sfermion mass spectrum those are derived from supersymmetric(SUSY) E_6 GUT with U(2) horizontal symmetric models, and investigate influence on some Flavor Changing Neutral Current(FCNC) processes from the structure of these soft masses.View full abstractDownload PDF (252K) -
Minoru NagaiArticle type: Article
2008 Volume 116 Issue 1 Pages A109-A111
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSWe discuss the quark EDMs and CEDMs in the MSSM with general flavor-changing terms in the squark mass matrices. In particular, the charged-Higgs mediated contributions to the down-quark EDM and CEDM are evaluated at two-loop level. We point out that these two-loop contributions may dominate over the one-loop gluino-contribution even when the squark and gluino masses are around few TeV and tan β is moderate.View full abstractDownload PDF (268K) -
Toshifumi Jittoh, Kazunori Kohri, Masafumi Koike, Joe Sato, Takashi Sh ...Article type: Article
2008 Volume 116 Issue 1 Pages A112-A113
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSThe little hierarchy problem is a fine tuning problem about masses of scalar top and Higgs in MSSM. We considered the light Higgs scenario to reduce tuning about this problem and found parameter regions where tuning is best relaxed. To discuss cosmological appropriateness of this regions, we calculated thermal relic denisty of the lightest neutralino in the parameter region.View full abstractDownload PDF (155K) -
S-G.Kim Kim, M. Kohda, N. Maekawa, K. Nagao, K. SakuraiArticle type: Article
2008 Volume 116 Issue 1 Pages A114-A116
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSThe little hierarchy problem is a fine tuning problem about masses of scalar top and Higgs in MSSM. We considered the light Higgs scenario to reduce tuning about this problem and found parameter regions where tuning is best relaxed. To discuss cosmological appropriateness of this regions, we calculated thermal relic denisty of the lightest neutralino in the parameter region.View full abstractDownload PDF (255K) -
Shigeki Matsumoto, Joe Sato, Masato Senami, Masato YamanakaArticle type: Article
2008 Volume 116 Issue 1 Pages A117-A119
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSRelic abundance of dark matter is investigated in the framework of universal extra dimension models with right-handed neutrinos. These models are free from the serious Kaluza-Klein(KK) graviton problem that the original universal extra dimension model possesses. The first KK particle of the right-handed neutrino is a candidate for dark matter in this framework. When ordinary neutrino masses are large enough such as the degenerate mass spectrum case, the dark matter relic abundance can change significantly. The scale of the extra dimension consistent with cosmological observations can be 500 GeV in the minimal setup of universal extra dimension models with right-handed neutrinos.View full abstractDownload PDF (284K) -
Sujoy PoddarArticle type: Article
2008 Volume 116 Issue 1 Pages A120-A123
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSRegions of the parameter space in the minimal super-gravity(mSUGRA) model with small m_0 and small m_<1/2> consistent with the WMAP data on dark matter relic density and the bound on the mass of the lightest Higgs scalar from LEP2(m_h > 114.4 GeV) open up if the rather adhoc assumption A_0=0 is relaxed. For moderate to large negative values of A_0 in several processes including lightest supersymmetric particle(LSP) pair annihilation, LSP-lighter tau slepton (τ^^〜_1) co-annihilation and LSP lighter top squark (t^^〜_1) co-annihilation contribute to the observed dark matter relic density. Such a t^〜_1 can be observed at the current experiments at the Tevatron. At the LHC a very distinctive semi-inclusive signature τ^±+X_τ(anything without a tau lepton) with a characteristic size much larger than e^±+X_e or μ^±+X_μ events can be observed during the early runs.View full abstractDownload PDF (302K) -
Jae-hyeon ParkaArticle type: Article
2008 Volume 116 Issue 1 Pages A124-A126
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSWe study quark and lepton sector flavor violations in a supersymmetric SU(5) grand unification scenario in a model-independent way employing mass insertions. In many cases, a lepton flavor violating process provides a stringent constraint on the flavor structure of right-handed down-type squarks. In particular, μ→eγ turns out to be highly susceptible to the 1-3 and 2-3 mixings thereof, due to the radiative correction from the top Yukawa coupling to the scalar mass terms of 10. We also discuss ways to maintain the power of leptonic restrictions even after incorporating a solution to fix the incorrect quark-lepton mass relations.View full abstractDownload PDF (305K) -
M. Ishiduki, S.-G. Kim, N. Maekawa, K. Sakurai, T. YoshikawaArticle type: Article
2008 Volume 116 Issue 1 Pages A127-A129
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSWe study models of spontaneous CP violation within the framework of E_6 SUSY GUT on which horizontal symmetry and anomalous U(1) symmetry are imposed. The VEVs of the avon fields break horizontal symmetry and CP symmetry spontaneously and simultaneously, and generate Yukawa couplings of the MSSM with their phases as well as realistic hierarchies. The current model exhibits several steps to ease SUSY CP problem without destabilizing the weak scale. Each symmetry employed in the model plays crucial roles in realising above consequences.View full abstractDownload PDF (273K) -
Debottam DasArticle type: Article
2008 Volume 116 Issue 1 Pages A130-A133
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSThe phase parameters in low-energy supersymmetry(SUSY) models are highly constrained by the electric dipole moments(EDM) of the fermions. Further imposing radiative electroweak symmetry breaking(REWSB) condition results in a large degree of fine tuning of the phase parameters at the unification scale. In supergravity models, one finds highly fine tuned values for the phases of the bilinear Higgs coupling parameter B at the unification scale(GUT) scale which in turn also constrain the phase of universal trilinear coupling A_0. We analysed how a GUT inspired definite non-universal gaugino mass(NUGM) model can reduce such fine-tuning keeping superparticle masses within the naturalness domain.View full abstractDownload PDF (300K) -
Tetsutaro HigakiArticle type: Article
2008 Volume 116 Issue 1 Pages A134-A136
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSWe study KKLT type moduli stabilization with F-term uplifting, and soft supersymmetry breaking terms. We assumed that F-term uplifting sector is one loop corrected O'Raifeartaigh model.View full abstractDownload PDF (232K) -
Yuji OmuraArticle type: Article
2008 Volume 116 Issue 1 Pages A137-A139
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSWe study the relations among R-symmetry, supersymmetry breaking and metastability in N=1 supergravity with a continuous global U(1)_R symmetry. First we show that the general argument by Nelson and Seiberg(NS) for dynamical supersymmetry(SUSY) breaking still holds with local SUSY, except for a certain nontrivial case. Then, we discuss the relation between explicit R-symmetry breaking terms and the metastabilities of SUSY breaking vacua in O'Raifeartaigh model. We show that the R-breaking terms are basically divided into two categories. One of them generates SUSY solutions which disappear if we uplift the original SUSY breaking minimum to a Minkowski vacuum. In such sense, not all of the explicit R-breaking terms leads to a metastability of the SUSY breaking vacuum.View full abstractDownload PDF (265K) -
Seongcheol KimArticle type: Article
2008 Volume 116 Issue 1 Pages A140-A142
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSThe situation that a scalar field provides the source of the accelerated expansion of the universe while rolling down its potential is common in both the simple models of the primordial inflation and the quintessence-based dark energy models. Motivated by this point, we address the possibility of causing the current acceleration via the primordial inflation using a simple model based on hybrid inflation. We trigger the onset of the motion of the quintessence field via the waterfall field. We also briefly discuss the possible implementation of our scenario in supersymmetric theories.View full abstractDownload PDF (299K) -
Ryo TakahashiArticle type: Article
2008 Volume 116 Issue 1 Pages A143-A145
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSWe present detailed analyses of the vacuum structure of the scalar potential in a supersymmetric Mass Varying Neutrinos model. The observed dark energy density is identified with false vacuum energy and the dark energy scale of order (10^<-3>eV)^4 is understood by gravitationally suppressed supersymmetry breaking scale, F(TeV)^2/M_<P1>, in the model.View full abstractDownload PDF (230K) -
Hiroyuki AbeArticle type: Article
2008 Volume 116 Issue 1 Pages A146-A148
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSWe present a systematic. way for deriving a four-dimensional(4D) effective action of the five-dimensional(5D) orbifold supergravity respecting the N=1 off-shell structure. As an illustrating example, we derive a 4D effective theory of the 5D gauged supergravity with a universal hypermultiplet and generic gaugings, which includes the 5D heterotic Mtheory and the supersymmetric Randall-Sundrum model as special limits of the gauging parameters. We show the vacuum structure of such model, especially the nature of moduli stabilization, introducing perturbative superpotential terms at the orbifold fixed points.View full abstractDownload PDF (269K) -
Kang-Sin ChoiArticle type: Article
2008 Volume 116 Issue 1 Pages A149-A151
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSA different scheme of the supersymmetric Grand Unification is given as a low energy limit of an intersecting brane model. A linearly growing VEV of a scalar, from the extra dimensional component of gauge a field, give rise to chiral fermions of bifundamental representation. A unification picture and the weak mixing angle is also discussed.View full abstractDownload PDF (260K) -
Kei-Jiro TakahashiArticle type: Article
2008 Volume 116 Issue 1 Pages A152-A154
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSI investigate compactifications on non-factorizable torus defined by E_6 root lattice, which allows automorphism of Z_3×Z_3 in. Interestingly some of the twisted sectors from the Z_3×Z_3 orbifold on E_6 root lattice have just three fixed tori respectively, and generate three degenerate massless states. We assume only non-standard gauge embeddings and find that it leads to three-family SU(5) and SO(10) GUT-like models. These models also include strongly coupled sectors in the low energy and messenger states charged with both hidden and visible sectors.View full abstractDownload PDF (228K) -
Satoru KanekoArticle type: Article
2008 Volume 116 Issue 1 Pages A155-A157
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSIn this work, we propose a predictive A_4 avour symmetry model which implies a lower bound on the neutrinoless double beta decay rate, and a direct correlation between the expected magnitude of CP violation in neutrino oscillations and the value of sin^2 θ_<13>, as well as a nearly maximal CP phase δ.View full abstractDownload PDF (229K) -
Hiroshi OkadaArticle type: Article
2008 Volume 116 Issue 1 Pages A158-A160
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSIt is now clear that the masses of the neutrino sector are much lighter than those of the other three sectors.There are many attempts to explain the neutrino masses radiatively by means of inert Higgses, which don't have vacuum expectation values. Then one can discuss cold dark matter candidates, because of no needing so heavy particles and having a Z_2 parity symmetry corresponding to the R-parity symmetry of the MSSM. The most famous work would be the Zee model. Recently a new type model along this line of thought was proposed by Mr. E. Ma. We paid attention to this idea. We introduce a avor symmetry based on a dihedral group D_6 to constrain the Yukawa sector. For the neutrino sector, we find that the maximal mixing of atmospheric neutrinos is realized, it can also be shown that only an inverted mass spectrum, the value of |V_<MNS_<13>>| is 0.0034 and so on. For the fermionic CDM candidates, we find that the mass of the CDM and the inert Higgs should be larger than about 230 and 300 GeV, respectively. If we restrict ourselves to a perturbative regime, they should be lighter than about 750 GeV.View full abstractDownload PDF (212K) -
Mihoko M. Nojiri, Michihisa TakeuchiArticle type: Article
2008 Volume 116 Issue 1 Pages A161-A163
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSAt the LHC, q^^〜_Lq^^〜_L production is one of the main SUSY production processes in the MSSM. This process is one of the sources of same sign two lepton(SS2l) events, however, gluino production also contributes to this channel. We developed a method to identify gluino and squark production separately in the SS2l channel, based on cuts on the kinematical configuration of the jets. We applied the method to the MSSM, a model with an extended gluino sector(EGM), and the Littlest Higgs model with T-parity(LHT), and found a distinctive difference between these models when considering the numbers of SS2l events selected by the cuts. This talk is based on ref.View full abstractDownload PDF (272K) -
Yuji KajiyamaArticle type: Article
2008 Volume 116 Issue 1 Pages A164-A166
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSIn this talk, we investigate Lepton Flavor Violating(LFV) tau decay by R-Parity Violating(RPV) operators controlled by a non-Abelian discrete Q_6 family symmetry. We assume that only a family symmetry determines the whole avor structure of a model, and the model indicates specific predictions of LFV tau decay processes by RPV operators. We predict BR(τ→3e)/BR(τ→3μ)〜4m^2_μ/m^2_μ/m^2_τ in a Q_6 family symmetric model.View full abstractDownload PDF (243K) -
Hiroshi OhkiArticle type: Article
2008 Volume 116 Issue 1 Pages A167-A169
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSWe study anomalies of discrete R-symmetry in heterotic orbifold models. We show that the mixed anomalies for gauge groups satisfy the universal Green-Schwartz(GS) condition, indicating that these anomalies are canceled by the GS mechanism. We find an exact relation between the anomaly coefficients of the discrete R-symmetries and oneloop beta function coefficients from the explicit formula of the anomaly coefficients of the discrete R-symmetries.View full abstractDownload PDF (223K) -
Haruhiko Terao, Akito TsuchiyaArticle type: Article
2008 Volume 116 Issue 1 Pages A170-A172
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSIt has been often claimed that the Peccei-Quinn symmetry solves the strong CP problem in an elegant way, however explict breaking terms must be suppressed extremely. If the PQ symmetry realizes accidentally like other global symmetries in the standard model, then this poses a very puzzling porblem. We consider that a large anomalous dimension of the so-called Peccei-Quinn field may solve this fine-tuning problem of the axion models. We showed that a large anomalous dimension can be given to a scalar field in some strongly coupled gauge-Yukawa theories and also that we may construct an explicit axion model by applying this mechanism.View full abstractDownload PDF (291K) -
Kazunari Shima, Motomu Tsuda, Wolfdieter LangArticle type: Article
2008 Volume 116 Issue 1 Pages A173-A175
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSBasic ideas of nonlinear supersymmetric general relativity(NLSUSY GR) are explained and some cosmological and the low emergy particle physics consequences are discussed.View full abstractDownload PDF (243K) -
Jinn-Ouk GongArticle type: Article
2008 Volume 116 Issue 1 Pages A176-A178
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSWe explore a new possibility that some inflaton fields in multi-field inflation models satisfy the observed value of the spectral index so that the curvature perturbation generated by them through post-inflationary dynamics may be relevant for the current observations. We illustrate this point using a simple and reasonable multi-field chaotic inflation model motivated from string theory.View full abstractDownload PDF (265K) -
Masako Hayashi, Tomohiro InagakiArticle type: Article
2008 Volume 116 Issue 1 Pages A179-A181
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSWe study thermal and curvature effects to spontaneous symmetry breaking in a four-fermion interaction model. Dynamical mass, energy density and cosmological constant are evaluated in D-dimensional static universe with positive curvature R⨂S^<D-1>. By solving Einstein equation numerically, the relationship between the temperature and the scale factor of the spacetime is obtained as the solution.View full abstractDownload PDF (194K) -
Keiji IgiArticle type: Article
2008 Volume 116 Issue 1 Pages A182-A185
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
JOURNAL FREE ACCESSWe test the universality of B in front of log^2(s/s_0) for all the total hadronic cross sections through investigations of the value of B for π^±p(K^±p) and p^^-p, pp scatterings. We search for the simultaneous best fit to σ_<tot> and ρ ratios, using a constraint from the FESR of the P' type for π^⨣p scatterings and constraints which are free from unphysical regions for p^^-p,pp and K^±p scatterings. By including rich informations of the low-energy scattering data owing to the use of FESR, the errors of B parameters decrease especially for πp. The resulting value of B_<pp> is consistent with B_<πp> within two standard deviation, which appears to support the universality hypothesis.View full abstractDownload PDF (273K) -
Article type: Appendix
2008 Volume 116 Issue 1 Pages 1-
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
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Article type: Appendix
2008 Volume 116 Issue 1 Pages App2-
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
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Article type: Appendix
2008 Volume 116 Issue 1 Pages App3-
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
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Article type: Cover
2008 Volume 116 Issue 1 Pages Cover2-
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
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Article type: Cover
2008 Volume 116 Issue 1 Pages Cover3-
Published: April 20, 2008
Released on J-STAGE: October 02, 2017
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