KEK Theory Meeting on Particle Physics Phenomenology (KEK-PH2018 winter) and 3rd KIAS-NCTS-KEK workshop on Particle Physics Phenomenology

Session

Parallel Session 2

4 Dec 2018, 15:30

Conveners

Parallel Session 2

• Daisuke Nomura (KEK)

Parallel Session 2

• Daisuke Nomura (KEK)

Parallel Session 2

• Toru Goto (KEK)

Parallel Session 2

• Toru Goto (KEK)

Parallel Session 2

• Satoshi Mishima (KEK)

Parallel Session 2

• Satoshi Mishima (KEK)

35. Vacuum decay rates in the standard model and beyond

Yutaro Shoji (KMI, Nagoya U.)

04/12/2018, 15:30

The electroweak vacuum is not absolutely stable in the standard model and various models beyond the standard model. This is due to an appearance of another deeper vacuum, into which the electroweak vacuum can decay. We have performed one-loop calculations of the decay rates in various models including the standard model. In this talk, I explain current status of our analysis on models beyond...

36. Lower Bound on the Bounce Action

Ryosuke Sato (DESY)

04/12/2018, 15:45

To calculate lifetime of false vacuum, we have to estimate bounce action. We derive a lower bound on the bounce action without solving equation of motion of scalar field explicitly. This technique is useful to analyze models with large number of scalar fields.

37. De Sitter swampland conjecture and cosmological applications

Hiroki Matsui (Tohoku University)

04/12/2018, 16:00

38. Leptogenesis via active neutrino oscillation

Wen Yin (KAIST)

04/12/2018, 16:15

The possibility of generating the baryon asymmetry of the Universe via flavor oscillation in the early Universe is discussed. After the inflation, leptons are born in some states, travel in the medium, and are eventually projected onto flavor eigenstates due to the scattering via the Yukawa interactions. By using the Lagrangian of the Standard Model with the Majorana neutrino mass terms, llHH,...

43. Indirect search for CP-violation in the Higgs sector by the precision test of Higgs couplings

Mitsunori Kubota (Osaka University)

04/12/2018, 16:45

Although the discovered Higgs boson appears to favor the standard model, the structure of the Higgs sector is not clear yet. For instance, we can consider some extension of the Higgs sector while we keep consistency in the collider experiments. In particular, CP-violating Higgs sector is motivated by the baryon number asymmetry of the Universe. In this talk, we discuss how effects of the...

44. Revisiting Flavor and CP Violation in Supersymmetric SU(5) with Right-Handed Neutrinos

Takumi Kuwahara (Institute for Basic Science)

04/12/2018, 17:00

We revisit the minimal supersymmetric SU(5) grand unified theory with three right-handed neutrinos in which universality conditions for soft-supersymmetry breaking parameters are imposed at the Planck scale. If the Majorana masses for the neutrinos are around 10^15 GeV, large mixing angles and phases in the neutrino sector lead to flavor-violation and CP-violation in the right-handed down...

45. Non-perturbative effects of loop-induced mixing: Majorana fields and CP violation

Chang-Hun Lee (NCTS)

04/12/2018, 17:15

In the loop-induced mixing of multiple flavors of fields, there exist non-perturbative effects which produce phenomenolgical effects which have been improperly considered so far especially when the mass differences among flavors are small. In this talk, I will discuss how to correctly handle such effects and their phenomenological implications especially in connection with CP violation. I will...

46. CP violating mode of the stoponium decay into Zh

Po Yen Tseng

04/12/2018, 17:30

We show that a novel decay mode Zh of the bound state of stop-anti-stop pair in the ground state may have a significant branching ratio if the CP violating mixing appears in the stop sector, even after we apply the stringent constraint from the measurement of the electric dipole moment (EDM) of the electron. We show that the branching ratio can be as large as 10% in some parameter space that...

51. Sbottoms as probes to MSSM with Nonholomorphic Soft Interactions

Samadrita Mukherjee (Indian Association for the Cultivation of Science)

05/12/2018, 15:30

Presence of nonholomorphic soft SUSY breaking terms is known to be a possibility in the popular setup of the Minimal Supersymmetric Standard Model (MSSM). It has been shown that such a scenario known as NonHolomorphic Supersymmetric Standard Model (NHSSM) could remain ‘natural’ (i.e., not fine-tuned) even in the presence of a rather heavy higgsino-like LSP. However, it turns out that...

52. SUSY model for muon g-2 anomaly and dark matter, and its implications

Norimi Yokozaki (Tohoku University)

05/12/2018, 15:45

Since constraints from LHC SUSY searches and direct detection experiments of dark matter become increasingly stringent, it becomes non-trivial task to find a SUSY model which can explain the muon g-2 anomaly and the nature of dark matter, simultaneously. In this talk, I will present a relatively simple SUSY model solving these two important issues, satisfying the LHC and other constraints. It...

53. Spontaneous SUSY breaking in natural SO(10) GUT

Nobuhiro Maekawa (Nagoya Univ. KMI)

05/12/2018, 16:00

If from natural SO(10) GUT, in which DT splitting can be realized with natural assumption in which all interactions allowed by the symmetry are introduced with O(1) coefficients, one singlet field is reduced, SUSY is spontaneously broken in meta-stable vacuum. Although gaugino masses become much smaller than sfermion masses, we discuss a few interesting phenomenological predictions of this scenario.

54. Phenomenology in the model with parity symmetry

Yuji Omura (KMI, Nagoya Univ.)

05/12/2018, 16:15

We construct an extended Standard Model (SM), motivated by the strong CP problem and the dark matter. In our model, the parity symmetry is conserved, introducing the extra gauge symmetry, $SU(2{)}_R\yen timesU(1{)}_R$. The charges of $SU(2{)}_R\yen timesU(1{)}_R$ are assigned to the mirror fields in the same way as in the SM, but the chirality of the extra fermions is opposite to respect the parity...

59. Neutral Naturalness and its UV realization

Ling-Xiao Xu (Peking University)

05/12/2018, 16:45

We will present a neutral naturalness model with emphasizing the realistic misalignment between the electroweak scale and the new physics scale, and we will discuss its Ultraviolet realization in holographic Higgs setup, which realizes the finiteness of the Higgs potential.

60. Composite 2 Higgs doublet model

Kei Yagyu (Seikei University)

05/12/2018, 17:00

We discuss composite 2 Higgs doublet models based on the global symmetry breaking SO(6) to SO(4)*SO(2), where 2 Higgs doublets emerge as a pseudo Nambu-Goldstone bosons. The Higgs potential is generated at one-loop level via the Coleman-Weinberg mechanism. We show that the prediction of the Higgs boson mass spectrum and couplings can be different from those in the minimal supersymmetric standard model.

61. Matching renormalisable couplings between generic theories

Johannes Braathen (Osaka University)

05/12/2018, 17:15

The precise study of the Higgs boson properties -- in particular its mass and couplings -- is of the utmost importance for the investigation of BSM models with extended Higgs sectors. As New Physics currently seems to be driven to higher scales by experimental searches, the framework of Effective Field Theory becomes necessary to address the large mass hierarchies that appear in calculations....

62. Machine learning with augmentation for boosting di-Higgs searches

Kayoung Ban (Yonsei University)

05/12/2018, 17:30

Augmentation of invisible information with respect to many hypothetical models of background and signal processes, can highly improve the performance of the machine learning classifiers for HEP event discrimination. In this regard di-Higgs searches in the channels with multiple invisible final states, is one of the most important applications. Focusing on the di-Higgs channels with 2 bottom...

67. Lattice calculation of B to D(*) semileptonic form factor and determination of |Vcb|

Jaehoon Leem (Korea Institute For Advanced Study)

06/12/2018, 15:30

We report our works on calculation of exclusive B-meson decays to charmed mesons. In lattice simulation, we use the Oktay-Kronfeld action for the bottom and the charmed quark and HISQ action for the light quarks. We report how discretization error in the lattice simulation can be controlled in systematic way.

68. SMEFT top-quark effects on \Delta F=2 observables

Daiki Ueda (Sokendai)

06/12/2018, 15:45

We investigate model independent top-quark corrections to ∆F = 2 processes within the framework of the Standard Model Effective Field Theory. Dimension-six ∆F = 1 operators contribute to them though renormalization group evolutions and matching conditions. We provide a complete one-loop matching formula from the top quarks for ∆F = 2 transitions. We also demonstrate these corrections on ∆MBs...

69. Flavon Stabilization in Models with Discrete Flavor Symmetry

So Chigusa (University of Tokyo)

06/12/2018, 16:00

We propose a simple mechanism for stabilizing flavon fields with aligned vacuum structure in models with discrete flavor symmetry. The basic idea is that flavons are stabilized by the balance between the negative soft mass and non-renormalizable terms in the potential. We explicitly discuss how our mechanism works in A4 flavor model, and show that the field content is significantly simplified....

70. Test of the $R(D^{(\ast )})$ anomaly at the LHC

Syuhei Iguro (Nagoya University)

06/12/2018, 16:15

There are discrepancies between the experimental results and the Standard Model predictions, in the lepton flavor universality of the semileptonic $B$ decays: $B\yen to{D}^{(\ast )}\yen ell\yen nu$. As the new physics interpretations, new charged vector and charged scalar fields, that dominantly couple to the second and third generations, have been widely discussed. In this work, we study the signals of the...

74. Leptoquark interpretations of B anomaly and its implications on top quark physics

Peiwen Wu (Korea Institute For Advanced Study)

06/12/2018, 16:45

Recently, various leptoquark models have been investigated in terms of interpreting the recent B meson anomalies. We study the possible implications of relevant leptoquark scenarios on the top quark observables.

75. Tomography by neutrino pair beam

Hirashi Okui (Niigata University)

06/12/2018, 17:00

We consider the neutrino tomography. The idea of neutrino tomography is the imaging of the Earth ’s interior structure by using the neutrino. We assume the neutrino pair beam which has recently been proposed as neutrino source. The beam produces a large amount of neutrino and antineutrino pairs from the circulating partially stripped ions and provides the possibility to measure precisely the...

76. Muon decay into an electron and a light boson in a muonic atom

Yuichi Uesaka (Saitama University)

06/12/2018, 17:15

The charged lepton flavor violation (CLFV) is a good probe to search for new physics beyond the standard model. If there is a neutral boson X which is lighter than muon and has CLFV interaction, a muon can decay into an electron and an X, i.e. mu-> e+X. The search for this process is expected to constraint the property of X. In this talk, we focus on a search for the rare decay of muon in a...

77. Improved analysis for lepton-nucleus CLFV scattering ${\ell }_{i}N\to {\ell }_{j}X$ by scalar interaction

Masato Yamanaka (Kyushu Sangyo University)

06/12/2018, 17:30

We revisit charged lepton flavor violating (CLFV) scattering ${\ell }_{i}N\to {\ell }_{j}X$ mediated by scalar interaction. We point out that a new subprocess ${\ell }_{i}g\to {\ell }_{j}g$ via the effective interactions of CLFV mediator and gluon gives large contribution. Furthermore, in the light of quark number conservation, we consider quark pair-production processes $\ell_{i}g \to \ell_{j} Q...