The dark photon and the axion (or axionlike particle) are popular light particles of the hidden sector. Each of them has been actively searched for through the couplings called the vector portal and ...the axion portal. We introduce a new portal connecting the dark photon and the axion (axion-photon-dark photon, axion-dark photon-dark photon), which emerges in the presence of the two particles. This dark axion portal is genuinely new couplings, not just from a product of the vector portal and the axion portal, because of the internal structure of these couplings. We present a simple model that realizes the dark axion portal and discuss why it warrants a rich phenomenology.
We introduce a natural origin of the Peccei-Quinn (PQ) symmetry with a sufficiently good precision. In the standard model, the baryon number symmetry U(1)B arises accidentally due to the SU(3)C color ...gauge symmetry, and it protects the proton from a decay at a sufficient level. Likewise, if there is an SU(N) gauge symmetry in the hidden sector, an accidental hidden baryon number symmetry U(1)BH can appear. The hidden baryon number is solely obtained by the structure of the SU(N) group. In particular, the quality of the U(1)BH can be arbitrarily good for an asymptotically-free theory with large enough N. The U(1)BH can be identified as a PQ symmetry. Using our findings, we build two types of novel composite axion models: a model where only one SU(N) gauge symmetry is required to both guarantee the quality and break the U(1)BH, and a model with SU(N) × SU(M) gauge symmetry where the exotic quarks responsible to the axion-gluon coupling do not confine into exotic hadrons through the dynamical breaking of the PQ symmetry, and have masses of TeV scales.
A
bstract
We study the right-handed neutrino (RHN) dark matter candidate in the minimal U(1)
B−L
gauge extension of the standard model. The U(1)
B−L
gauge symmetry offers three RHNs which can address ...the origin of the neutrino mass, the relic dark matter, and the matter-antimatter asymmetry of the universe. The lightest among the three is taken as the dark matter candidate, which is under the
B
−
L
gauge interaction. We investigate various scenarios for this dark matter candidate with the correct relic density by means of the freeze-out or freeze-in mechanism. A viable RHN dark matter mass lies in a wide range including keV to TeV scale. We emphasize the sub-electroweak scale light
B
−
L
gauge boson case, and identify the parameter region motivated from the dark matter physics, which can be tested with the planned experiments including the CERN SHiP experiment.
We investigate the implications of the dark axion portal interaction, the axion-photon-dark photon vertex, for the future experiments SHiP and FASER. We also study the phenomenology of the combined ...vector portal (kinetic mixing of the photon and dark photon) and dark axion portal. The muon g−2 discrepancy is unfortunately not solved even with the two portals, but the low-energy beam dump experiments with monophoton detection capability can open new opportunities in light dark sector searches using the combined portals.
Objective
Despite a growing literature on the impact of economic nationalism on public attitudes toward foreign direct investment (FDI) inflows, public attitudes toward U.S. FDI outflows have been ...overlooked. We examine U.S. residents’ attitudes toward FDI outflows to two host countries viewed unfavorably by the American public, Mexico and China, and the extent to which providing accurate information on FDI flows between the United States and these countries affects the biases toward American investment in these countries.
Methods
We implemented a vignette experiment on respondents from 11 southern states in the United States.
Results
We find little support for the existence of bias toward Mexico or China as destinations for American investment, nor do we find that providing accurate information on bilateral FDI flows affects perceptions of U.S. FDI outflows to these countries. Instead, individuals' economic self‐interest and sociotropic concerns influence their attitudes toward FDI outflows.
Conclusions
Individuals' preferences toward U.S. FDI outflows are not shaped by biases toward investment destinations but by their concerns regarding the economic and security consequences of American overseas investment.
A nuclear reactor is a powerful tool to study neutrinos and light dark sector particles. Some reactor experiments have already proven to be extremely useful in these searches. Considering the great ...interest in the power of the Intensity Frontier to search for new light particles, it would be desirable to explore the possibility of exploiting the existing reactor power sources for particle physics research. We suggest a new reactor experiment searching for the dark sector. The dark photon can be produced in a reactor core and decay into a photon and an axion in the presence of the dark axion portal through an axion-photon-dark photon vertex. We investigate the potential to search for this new vertex with a monophoton signature and present the expected sensitivities at some of the existing reactor neutrino experiment detectors.
We present a new mechanism to produce the dark photon (γ′) in the early Universe with the help of the axion (a) using a recently proposed dark axion portal. The dark photon, a light gauge boson in ...the dark sector, can be relic dark matter if its lifetime is long enough. The main process we consider is a variant of the Primakoff process fa→fγ′ mediated by a photon, which is possible with the axion–photon–dark photon coupling. The axion is thermalized in the early Universe because of the strong interaction and it can contribute to the nonthermal dark photon production through the dark axion portal coupling. It provides a two-component dark matter sector, and the relic density deficit issue of the axion dark matter can be addressed by the compensation with the dark photon. The dark photon dark matter can also address the reported 3.5 keV x-ray excess via the γ′→γa decay.
Abstract
Pharmacogenomics aims to provide personalized therapy to patients based on their genetic variability. However, accurate prediction of cancer drug response (CDR) is challenging due to genetic ...heterogeneity. Since clinical data are limited, most studies predicting drug response use preclinical data to train models. However, such models might not be generalizable to external clinical data due to differences between the preclinical and clinical datasets. In this study, a Precision Medicine Prediction using an Adversarial Network for Cancer Drug Response (PANCDR) model is proposed. PANCDR consists of two sub-models, an adversarial model and a CDR prediction model. The adversarial model reduces the gap between the preclinical and clinical datasets, while the CDR prediction model extracts features and predicts responses. PANCDR was trained using both preclinical data and unlabeled clinical data. Subsequently, it was tested on external clinical data, including The Cancer Genome Atlas and brain tumor patients. PANCDR outperformed other machine learning models in predicting external test data. Our results demonstrate the robustness of PANCDR and its potential in precision medicine by recommending patient-specific drug candidates. The PANCDR codes and data are available at https://github.com/DMCB-GIST/PANCDR.
The dark axion portal is a recently introduced portal between the standard model and the dark sector. It connects both the dark photon and the axion (or axionlike particle) to the photon ...simultaneously through an anomaly triangle. While the vector portal and the axion portal have been popular venues to search for the dark photon and axion, respectively, the new portal provides new detection channels if they coexist. The dark axion portal is not a result of the simple combination of the two portals, and its value is not determined by the other portal values; it should be tested independently. In this paper, we discuss implications of the new portal for the leptonic g − 2, B factories, fixed target neutrino experiments and beam dumps. We provide the model-independent constraints on the axion-photon-dark photon coupling and discuss the sensitivities of the recently activated Belle-II experiment, which will play an important role in testing the new portal.
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