It is believed that there are more fundamental gauge symmetries beyond those described by the Standard Model of particle physics. The scales of these new gauge symmetries are usually too high to be reachable by particle colliders. Considering that the phase transition (PT) relating to the spontaneous breaking of new gauge symmetries to the electroweak symmetry might be strongly first order, we propose considering the stochastic gravitational waves (GW) arising from this phase transition as an indirect way of detecting these new fundamental gauge symmetries. As an illustration, we explore the possibility of detecting the stochastic GW generated from the PT of 
					 in the space-based interferometer detectors. Our study demonstrates that the GW energy spectrum is reachable by the LISA, Tianqin, Taiji, BBO, and DECIGO experiments only for the case where the spontaneous breaking of 
					 is triggered by at least two electroweak singlet scalars.
				

China

Wei Chao

Wen-Feng Cui

Huai-Ke Guo

Jing Shu

Gravitational wave imprint of new symmetry breaking JS is Supported by the National Natural Science Foundation of China (11647601, 11690022, 11675243) and also Supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB23030100). Wei Chao is Supported by the National Natural Science Foundation of China (11775025)

We consider right-handed neutrino dark matter N1 in local U(1)LÎ¼âLÏ -extended Ma model. With the light U(1)Î¼âÏ gauge boson ( mZâ²â¼O(100)Â MeV ) and small U(1)Î¼âÏ gauge coupling ( gZâ²â¼10â4â10â3 ) which can accommodate the muon (gâ2) anomaly and is still allowed by other experimental constraints, we show that we can get correct relic density of dark matter for wide range of dark matter mass ( M1â¼10â200Â GeV ), although the gauge coupling constant gZâ² is small. This is due to the fact that the annihilation cross section of dark matter pair is enhanced by M14/mZâ²4 in the processes N1N1âZâ²Zâ² or N1N1âZâ²H2 . We also consider the constraints from direct detection, collider searches.

South Korea

Seungwon Baek

Dark matter and muon ( g − 2) in local U(1)Lμ−Lτ -extended Ma model

Based on the Dyson-Schwinger Equations (DSEs), the two-quark vacuum condensate, the four-quark vacuum condensate, and the quark gluon mixed vacuum condensate in the non-perturbative QCD vacuum state are investigated by solving the DSEs with rainbow truncation at zero- and finite- temperature, respectively. These condensates are important input parameters in QCD sum rule with zero and finite temperature, and in studying hadron physics, as well as predicting the quark mean squared momentum m20- also called quark virtuality in the QCD vacuum state. The present calculated results show that these physical quantities are almost independent of the temperature below the critical point temperature Tc = 131 MeV, and above Tc the chiral symmetry is restored. For comparison we calculate the temperature dependence of the “in-hadron condensate” for pion. At the same time, we also calculate the ratio of the quark gluon mixed vacuum condensate to the two-quark vacuum condensate by using these condensates, and the unknown quark mean squared momentum in the QCD vacuum state has been obtained. The results show that the ratio m20(T) is almost flat in the temperature region from 0 to Tc, although there are drastic changes of the quark vacuum condensate and the quark gluon mixed vacuum condensate at the region. Our predicted ratio comes out to be m20(T)=2.41 GeV2 at the Chiral limit, which is consistent with other theory model predictions, and strongly indicates the significance that the quark gluon mixed vacuum condensate has played in the virtuality calculations.

Li-Juan Zhou

Bo Zheng

Hong-Wei Zhong

Wei-Xing Ma

Temperature dependence of quarks and gluon vacuum condensate in the Dyson-Schwinger Equations at finite temperatureSupported by National Natural Science Foundation of China (11365002), Guangxi Natural Science Foundation for Young Researchers (2013GXNSFBB053007, 2011GXNSFA018140), Guangxi Education Department (2013ZD049), Guangxi Grant for Excellent Researchers (2011-54), and Guangxi University of Science and Technology Foundation for PhDs (11Z16)

A QCD multiquark cluster system is studied in the relativistic harmonic oscillator potential model (RHOPM), and the electromagnetic form factors of the pion, proton and deuteron in the RHOPM are predicted. The calculated theoretical results are then compared with existing experimental data, finding very good agreement between the theoretical predictions and experimental data for these three target particles. We claim that this model can be applied to study QCD hadronic properties, particularly neutron properties, and to find six-quark cluster and/or nine-quark cluster probabilities in light nuclei such as helium 3He and tritium 3H. This is a problem of particular importance and interest in quark nuclear physics.

Qing Wu

Qian-Fei Xiang

Multiquark cluster form factors in the relativistic harmonic oscillator model