Article
Physics, Particles & Fields
Ethan Carragher, Will Handley, Daniel Murnane, Peter Stangl, Wei Su, Martin White, Anthony G. Williams
Summary: Models where the Higgs boson is a composite pseudo-Nambu-Goldstone boson provide attractive solutions to the Higgs mass naturalness problem. By examining three such models based on the minimal SO(5) -> SO(4) symmetry breaking pattern, it is found that each model can satisfy all constraints simultaneously and analysis of the collider phenomenology in viable regions reveals interesting results.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Yuichiro Nakai, Matthew Reece, Motoo Suzuki
Summary: The article discusses how hierarchical masses of quarks and leptons are addressed by imposing horizontal symmetries and how the same symmetries play a role in suppressing flavor violating processes in supersymmetric models. By combining the idea of spontaneous CP violation to control contributions to electric dipole moments (EDMs), the mass scale of supersymmetric particles can be lowered. Furthermore, models with two U(1) symmetries are found to provide a viable solution to the muon g - 2 anomaly, with future electron EDM experiments potentially probing the parameter space to explain the anomaly.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Lucien Heurtier, Hao-Lin Li, Huayang Song, Shufang Su, Wei Su, Jiang-Hao Yu
Summary: Investigation of a class of neutral naturalness models reveals the Higgs boson as a pseudo-Goldstone boson, with various dimension-six operators obtained by integrating out the radial mode. Chi (2) fit to precision measurements of Higgs couplings suggests a new physics scale could be explored up to 2.3 (2.4) TeV at future colliders, with limits comparable to indirect constraints from electroweak precision measurements.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Linda M. Carpenter, Matthew J. Smylie
Summary: We investigate the phenomenology of scalar fields in the weak and Higgs sectors of minimal R-symmetric models. We focus on the 'swino' and 'sbino', scalar partners to chiral fields that couple with electroweak gauge bosons in Dirac gaugino models. These fields exist in adjoint representations of SU(2) and U(1) and have both CP-even and CP-odd components. We summarize the interactions and compute the decay widths of these new states to one loop order. Additionally, we explore their contributions to the mass spectrum of MSSM sfermions and study their production cross sections and decay signatures in colliders. Our findings indicate that a large parameter space remains unconstrained by current collider data.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Physics, Particles & Fields
Ryo Nagai, Norimi Yokozaki
Summary: The study explores supersymmetric models without flavor violating masses at the tree-level to explain the muon g-2 anomaly, which can avoid constraints from LHC and the vacuum stability constraint in the stau-Higgs potential. Although minimal SUSY standard model does not induce large flavor violating processes, adopting a seesaw model can lead to significant lepton flavor violating processes such as mu -> e gamma and mu -> e conversion. These LFV processes will be observed in future experiments if right-handed neutrinos have masses heavier than 10^9 GeV, driven by successful leptogenesis.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Mariana Frank, Yasar Hicyilmaz, Subhadeep Mondal, Ozer Ozdal, Cem Salih Un
Summary: Researchers attribute deviations of the muon and electron magnetic moments from theoretical predictions to an additional U(1)' supersymmetric model, suggesting that discrepancies between the muon and electron anomalous magnetic moments are due to non-universal U(1)' charges. They demonstrate that in a minimally extended model, constraints are imposed on the model's spectrum by requiring both deviations to be satisfied, particularly on dark matter candidates and slepton masses. By choosing three benchmarks with distinct dark matter features, implications of the model at colliders are studied, focusing on variables that can distinguish their non-universal scenario from other U(1)' implementations.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Linda M. Carpenter, Taylor Murphy
Summary: In this study, the collider phenomenology of color-octet scalars in supersymmetric models with broken R symmetry is investigated. The explicit breaking of R symmetry affects decay rates and production cross sections of sgluons. While quantitatively impacting limits on color-octet scalars, models with broken R symmetry can still be accommodated by existing searches.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Nathalia Cardona, Andres Florez, Alfredo Gurrola, Will Johns, Paul Sheldon, Cheng Tao
Summary: The identity of Dark Matter (DM) is a highly discussed topic in particle physics, and Supersymmetry (SUSY) is an important extension of the standard model that can explain the nature of DM. A feasibility study was conducted at the CERN Large Hadron Collider to assess the long-term discovery potential of compressed SUSY models with higgsino-like states. The study found that using vector boson fusion (VBF) processes combined with specific requirements effectively reduces the background and provides new insights into the parameter space of DM models.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Astronomy & Astrophysics
Paulina Knees, Daniel E. Lopez-Fogliani, Carlos Munoz
Summary: In the framework of the mu nu SSM, the presence of right-handed neutrinos is analyzed to simultaneously solve the mu- and nu-problems in supersymmetry. Light neutrino masses and mixing angles are reproduced using just two right-handed neutrinos as part of the seesaw mechanism. A third right-handed neutrino behaves as a sterile neutrino with a mass in the range keV-MeV, and can be a good candidate for dark matter with a lifetime larger than the age of the Universe.
ASTROPARTICLE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Vernon Barger, Cash Hauptmann, Peisi Huang, Wai-Yee Keung
Summary: We propose a solution to the recent W mass measurement by embedding the Standard Model within E6 models. The presence of a new U(1) group shifts the W boson mass at the tree level and introduces a new gauge boson Z' which has been searched for at collider experiments. In this article, we identify the parameter space that explains the new W mass measurement and is consistent with current experimental Z' searches. As U(1) extensions can be accommodated in supersymmetric models, we also consider the supersymmetric scenario of E6 models, and show that a 125 GeV Higgs may be easily achieved in such settings.
Article
Physics, Particles & Fields
Jinmian Li, Junle Pei, Cong Zhang
Summary: This work investigates the self-interacting dark matter (SIDM) scenario in the general NMSSM and beyond, proposing an improved analytical expression for the self-interacting cross section of dark matter. By Monte Carlo simulation, the multiplicities and spectra of dark matter/mediator from Higgsino production and decay at the LHC are analyzed.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Waqas Ahmed, Shabbar Raza, Qaisar Shafi, Cem Salih Un, Bin Zhu
Summary: The SUSY model discusses the introduction of only electrically neutral states, doubling the number of states in the neutralino sector. It presents a rich phenomenology depending on dark matter composition. Collider experiments could test the lower bound on stop and gluino masses, while direct detection experiments will be able to test various dark matter solutions in the future.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Thi Nhung Dao, Martin Gabelmann, Margarete Muehlleitner, Heidi Rzehak
Summary: We present our computation of two-loop corrections to the Higgs boson masses of the CP-violating Next-to-Minimal Supersymmetric Standard Model (NMSSM). Our new corrections increase with rising lambda and kappa but remain overall below about 3% compared to our previously computed corrections, in the region compatible with perturbativity below the GUT scale. The impact of CP-violating phases in the new corrections is small, and we show how to efficiently treat the Goldstone Boson Catastrophe due to infrared divergences.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Junjie Cao, Jingwei Lian, Yusi Pan, Di Zhang, Pengxuan Zhu
Summary: A recent Fermilab report showed a significant discrepancy between muon g-2 and the standard model prediction. The study suggests that in the general next-to-minimal supersymmetric standard model (GNMSSM), a singlino-dominated neutralino could explain this discrepancy and make the detection of sparticles at the LHC challenging.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Manimala Chakraborti, Leszek Roszkowski, Sebastian Trojanowski
Summary: The recent confirmation by Fermilab-based Muon g-2 experiment of the (g - 2)(mu) anomaly has implications for allowed particle spectra in supersymmetry models with dark matter. The study found that general patterns of dark matter could be accommodated in unified SUSY models, unlike in simpler frameworks. Accessing these solutions at the LHC may be challenging due to compressed spectra.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Essodjolo Kpatcha, Inaki Lara, Daniel E. Lopez-Fogliani, Carlos Munoz, Natsumi Nagata
Summary: This study analyzes the impact of the mu nu SSM model on the muon g-2, solving the μ problem and reproducing neutrino data by the addition of right-handed neutrinos. The model naturally drives the masses of light left muon-sneutrino and wino through neutrino physics, increasing the chargino-sneutrino loop contribution to muon g-2 and bridging the gap between theoretical computation and experimental data.
EUROPEAN PHYSICAL JOURNAL C
(2021)
Article
Physics, Particles & Fields
John Ellis, Jason L. Evans, Natsumi Nagata, Keith A. Olive, L. Velasco-Sevilla
Summary: This study explores the possible values of the mu -> e gamma branching ratio and the electron dipole moment in no-scale SU(5) super-GUT models, considering various constraints. The results show that all model predictions are below current and prospective experimental sensitivities when taking into account dark matter density, Higgs mass, and current proton decay constraints. However, there may be limited regions in some models where mu -> e conversion on a heavy nucleus could be observable in the future.
EUROPEAN PHYSICAL JOURNAL C
(2021)
Article
Astronomy & Astrophysics
Tomohiro Abe, Koichi Hamaguchi, Natsumi Nagata
Summary: This study reexamines the inverse Primakoff scattering of axions and finds that the scattering cross section is overestimated for low-energy axions when using a form factor computed with a relativistic Hartree-Fock wave function compared to results based on the screened Coulomb potential. It is also discovered that inelastic scattering processes may dominate when the momentum transfer is small, and for high-energy axions, the total scattering cross section is well approximated by a simple expression with little dependence on atomic structure.
Article
Physics, Particles & Fields
John Ellis, Jason L. Evans, Natsumi Nagata, Keith A. Olive
Summary: In this study, a missing-partner model based on the minimal SU(5) gauge group was explored under the assumption of a super-GUT CMSSM scenario. The research identified regions of parameter space that meet constraints related to cosmological dark matter density, Higgs mass, and experimental limits, showing solutions that can satisfy these constraints simultaneously.
EUROPEAN PHYSICAL JOURNAL C
(2021)
Article
Physics, Particles & Fields
Sven Heinemeyer, Essodjolo Kpatcha, Inaki Lara, Daniel E. Lopez-Fogliani, Carlos Munoz, Natsumi Nagata
Summary: The mu nu SSM model is a highly predictive alternative to the MSSM, with the ability to explain discrepancies between experimental results for the anomalous magnetic moment of the muon and the Standard Model prediction. Recent MUON G-2 results show that significant regions of the model can account for new data on (g-2)(mu).
EUROPEAN PHYSICAL JOURNAL C
(2021)
Article
Physics, Particles & Fields
John Ellis, Jason L. Evans, Natsumi Nagata, Dimitri Nanopoulos, Keith A. Olive
Summary: In flipped SU(5) GUT models, scenarios involving strong couplings between the 10- and 5-dimensional GUT Higgs representations may lead to detectable proton decay in the Hyper-Kamiokande experiment. Furthermore, relaxing universality constraints on soft supersymmetry-breaking masses could result in a substantial contribution to g(mu) - 2.
EUROPEAN PHYSICAL JOURNAL C
(2021)
Article
Physics, Particles & Fields
Essodjolo Kpatcha, Inaki Lara, Daniel E. Lopez-Fogliani, Carlos Munoz, Natsumi Nagata, Hidetoshi Otono
Summary: The study analyzes the relevant signals at the LHC for a stop as the lightest supersymmetric particle (LSP) and discusses the results in the framework of the mu nu SSM. Stops are pair produced at the LHC, decaying with displaced vertices to a lepton and a bottom quark or a neutrino and a top quark.Using a data-driven method to sample the mu nu SSM, with special attention given to reproducing experimental data.
EUROPEAN PHYSICAL JOURNAL C
(2022)
Article
Physics, Particles & Fields
Koichi Hamaguchi, Natsumi Nagata, Maura E. Ramirez-Quezada
Summary: This work discusses the temperature observation of neutron stars as a promising way to probe models with weakly-interacting massive particles (WIMPs) coupled to muons. By efficiently capturing WIMPs through DM-muon or spin-dependent DM-nucleon scattering, neutron stars can exhibit a surface temperature much higher than predicted by the standard cooling theory. This effect is observable in old neutron stars and can provide insights into the parameters of such models.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Physics, Particles & Fields
Koichi Hamaguchi, Natsumi Nagata, Genta Osaki, Shih-Yen Tseng
Summary: We studied lepton dipole moments in an extension of the Standard Model, which includes vector-like leptons coupling only to second-generation leptons. Our model explains the muon g - 2 anomaly and holds consistent with experimental constraints on the electron EDM and Higgs decay. The generated EDMs, with magnitudes of approximately O(10-(22)) e middot cm for muon and O(10(-30)) e middot cm for electron, can be tested in future EDM measurements.
JOURNAL OF HIGH ENERGY PHYSICS
(2023)
Article
Physics, Particles & Fields
Kunio Kaneta, Natsumi Nagata, Keith A. Olive, Maxim Pospelov, Liliana Velasco-Sevilla
Summary: We revisited the calculation of EDMs in the CMSSM model, where the large mass of the Higgs boson coupled with the lack of discovery of supersymmetric particles at the LHC has pushed the supersymmetry breaking scale to several TeV or higher. Although one might expect this decoupling to have relaxed any bounds on the CP violating phases in the CMSSM, the experimental limits on EDMs, particularly the electron EDM, still allow constraints on theta(A) and theta(mu) on the order of (0.01-0.1)pi and (0.001-0.1)pi, respectively. We also discussed the impact of future experimental improvements on supersymmetric models.
JOURNAL OF HIGH ENERGY PHYSICS
(2023)
Article
Physics, Particles & Fields
A. Granelli, K. Hamaguchi, N. Nagata, M. E. Ramirez-Quezada, J. Wada
Summary: We discuss the thermal leptogenesis mechanism within the minimal gauged U(1) L-mu-L-t model to explain the observed baryon asymmetry of the Universe (BAU). In such framework, the predictable phases of the Pontecorvo-Maki-Nakagawa-Sakata neutrino mixing matrix and the sum of the Standard Model neutrino masses are due to a restricted neutrino mass matrix structure. Our analysis reveals that thermal leptogenesis is feasible within a wide parameter space, specifically for Yukawa couplings ranging from approximate unity to O(0.03-0.05) and mass of the lightest right-handed neutrino M1 greater than or similar to 10^(11-12) GeV, setting a leptogenesis scale in the considered model which is higher than that of the non-thermal scenario.
JOURNAL OF HIGH ENERGY PHYSICS
(2023)
Article
Astronomy & Astrophysics
Dhong Yeon Cheong, Koichi Hamaguchi, Yoshiki Kanazawa, Sung Mook Lee, Natsumi Nagata, Seong Chan Park
Summary: In axion models, the problem of gravitational violation of the Peccei-Quinn (PQ) symmetry due to axionic wormholes is addressed by introducing a nonminimal coupling of the axion field to gravity. The solution to the quality problem is found in the Palatini formulation, where the requested lower bound of the nonminimal coupling is slightly higher than that in the metric formulation.
Article
Astronomy & Astrophysics
Koichi Hamaguchi, Shihwen Hor, Natsumi Nagata
Summary: We revisit the minimal Nambu-Goldstone-Higgs supersymmetric (SUSY) SU(5) grand unified model and study its phenomenological implications. The Higgs sector possesses a global SU(6) symmetry and leads to light Higgs doublets, solving the doublet-triplet splitting problem. The model is more predictive than the minimal SUSY SU(5) due to the tightly restricted couplings of the Higgs sector. The perturbativity condition on the trilinear coupling of the adjoint Higgs field imposes limits on the wino and gluino masses.
Article
Astronomy & Astrophysics
Motoko Fujiwara, Koichi Hamaguchi, Natsumi Nagata, Jiaming Zheng
Summary: This paper investigates a new method of detecting dark matter through temperature observations of neutron stars. The study finds that for electroweak multiplet dark matter, this approach can reach parameter regions beyond the reach of future direct detection experiments.
Article
Astronomy & Astrophysics
Koichi Hamaguchi, Yoshiki Kanazawa, Natsumi Nagata
Summary: Global symmetries are expected to be violated by gravity, but a new coupling method can suppress the breaking effect in the presence of gravity, maintaining high-quality symmetry. This provides a new way to avoid the mass problem of global symmetries.
