作者机构：
[Xiao-Yu Lai] Department of Physics and Astronomy,Hubei University of Education,Wuhan 430205,China;[Xiao-Yu Lai] Research Center for Astronomy,Hubei University of Education,Wuhan 430205,China;[Cheng-Jun Xia] School of Information Science and Engineering,NingboTech University,Ningbo 315100,China;Institute of Astrophysics,Central China Normal University,Wuhan 430079,China;School of Physics,Peking University,Beijing 100871,China
关键词：
dense matter-equation of state;pulsars: general
摘要：
The state of supranuclear matter in compact stars remains puzzling, and it is argued that pulsars could be strangeon stars. The consequences of merging double strangeon stars are worth exploring, especially in the new era of multi-messenger astronomy. To develop the "strangeon kilonova" scenario proposed in Paper I, we make a qualitative description about the evolution of ejecta and light curves for merging double strangeon stars. In the hot environment of the merger, the strangeon nuggets ejected by tidal disruption and hydrodynamical squeezing would suffer from evaporation, in which process particles, such as strangeons, neutrons and protons, are emitted. Taking into account both the evaporation of strangeon nuggets and the decay of strangeons, most of the strangeon nuggets would turn into neutrons and protons, within dozens of milliseconds after being ejected. The evaporation rates of different particles depend on temperature, and we find that the ejecta could end up with two components, with high and low opacity respectively. The high opacity component would be in the directions around the equatorial plane, and the low opacity component would be in a broad range of angular directions. The bolometric light curves show that the spin-down power of the long-lived remnant would account for the whole emission of kilonova AT2017gfo associated with GW170817, if the total ejected mass ∼ 10−3 M⊙. The detailed picture of merging double strangeon stars is expected to be tested by future numerical simulations.
作者机构：
华中师范大学国家数字化学习工程技术研究中心 武汉430079;华中师范大学物理科学与技术学院 武汉430079;华中师范大学教育大数据应用技术国家工程实验室 武汉430079;[Qiuting C.; Yunze D.] College of Physical Science and Technology, Central China Normal University, Wuhan, 430079, China;[Yanwen W.] National Engineering Research Center for E-Learning, Central China Normal University, Wuhan, 430079, China, College of Physical Science and Technology, Central China Normal University, Wuhan, 430079, China
摘要：
1FGL J1018.6–5856 is a high mass gamma-ray binary containing a compact object orbiting around a massive star with a period of 16.544 d. If the compact object is a pulsar, non-thermal emissions are likely produced by electrons accelerated at the termination shock, and may also originate from the magnetosphere and the un-shocked wind of the pulsar. In this paper, we investigate the non-thermal emissions from the wind and the shock with different viewing geometries and study the multi-wavelength emissions from 1FGL J1018.6–5856. We present the analysis results of the Fermi/LAT using nearly 10 years of data. The phase-resolved spectra indicate that the Ge V emissions comprise a rather steady component that does not vary with orbital motion and a modulated component that shows flux maximum around inferior conjunction. The ke V/Te V light curves of 1FGL J1018.6–5856 also exhibit a sharp peak around inferior conjunction, which are attributed to the boosted emission from the shock, while the broad sinusoidal modulations could be originating from the deflected shock tail at a larger distance. The modulations of Ge V flux are likely caused by the boosted synchrotron emission from the shock and the IC emission from the unshocked pulsar wind, while the steady component comes from the outer gap of the pulsar magnetosphere.Finally, we discuss the similarities and differences of 1FGL J1018.6–5856 with other binaries, like LS 5039.
关键词：
non-Markovian environment;remote force detection;cavity optomechanics
摘要：
A scheme for remote weak-signal sensors is proposed, in which a coupled-resonator optical waveguide (CROW), as a transmitter, couples to a hybrid optomechanical cavity and an observing cavity at its two ends. Non-Markovian theory is employed to study the weak-force sensor by treating the CROW as a non-Markovian reservoir of cavity fields. The dissipationless bound states in the non-Markovian regime are conducive to remotely transmitting a signal in the CROW. Our results show that a sensor with ultrahigh sensitivity can be achieved with the assistance of bound states under certain parameter regimes.
作者机构：
Key Laboratory for Organic Electronics and Information Displays & Jiangsu Key Laboratory for Biosensors,Institute of Advanced Materials (IAM),Nanjing University of Posts & Telecommunications,9 Wenyuan Road,Nanjing 210023,China;Department of Physical Science and Technology,Central China Normal University,Wuhan 430079,China;Sauvage Center for Molecular Sciences,Hubei Key Lab on Organic and Polymeric Optoelectronic Materials,Department of Chemistry,Wuhan University,Wuhan 430072,China;Frontiers Science Center for Flexible Electronics (FSCFE),Shaanxi Institute of Flexible Electronics (SIFE) & Shaanxi Institute of Biomedical Materials and Engineering (SIBME),Northwestern Polytechnical University (NPU),127 West Youyi Road,Xi'an 710072,China;[Wei Huang; Wuji Wang; He Jiang; Ye Tao; Jibiao Jin; Runfeng Chen; Chao Zheng; Zijie Wang] 南京邮电大学
摘要：
Organic semiconductors with bipolar transporting character are highly attractive as they offer the possibility to achieve high optoelectronic performance in simple device structures. However, the continual efforts in preparing bipolar materials are focusing on donor-acceptor (D-A) architectures by introducing both electron-donating and electron-withdrawing units into one molecule in static molecular design principles. Here, we report a dynamic approach to construct bipolar materials using only electron-donating carbazoles connected by N-P=X resonance linkages in a donor-resonance-donor (D-r-D) structure. By facilitating the stimuli-responsive resonance variation, these D-r-D molecules exhibit extraordinary bipolar properties by positively charging one donor of carbazole in enantiotropic N+=P-X- canonical forms for electron transport without the involvement of any acceptors. With thus realized efficient and balanced charge transport, blue and deep-blue phosphorescent organic light emitting diodes hosted by these D-r-D molecules show high external quantum efficiencies up to 16.2% and 18.3% in vacuum-deposited and spin-coated devices, respectively. These results via the D-r-D molecular design strategy represent an important concept advance in constructing bipolar organic optoelectronic semiconductors dynamically for high-performance device applications.
作者机构：
[Jiang, Qian-Wen; Tan, Hua-Tang; Fang, Sen-Zhi; Wu, Qing-Lin; Li, Gao-Xiang; Dai, Yang] Cent China Normal Univ, Dept Phys, Wuhan 430079, Peoples R China.
通讯机构：
[Wu, Q.-L.] D;Department of Physics, China
关键词：
quantum optics;weak value;recycling
摘要：
Weak value amplification has shown its superiority in measurement of small physical effects. Here we introduce a signal-recycled weak-value-based velocity measurement strategy to decrease the attenuation of detected photons during the post-selection. Like the power-recycled scheme, we can improve the number of detected photons and signal-to-noise ratio of velocity by forming a cavity. However, optimal improvements of number of detected photons and signal-to-noise ratio cannot be obtained simultaneously in our signal-recycled scheme owing to the walk-off effect. Furthermore, we find that the reflected light is relatively strong compared with the power-recycled scheme, which may increase the collection-detection efficiency in prospective relevant experiment.
作者机构：
[Ketel, T.; Tuning, N.; Hynds, D.; Mauri, A.; Usachov, A.; Lukashenko, V; Kuindersma, H. S.; Heijhoff, K.; Veronesi, M.; Aaij, R.; Snoch, A.; van Beuzekom, M.; Martinez, M. Lucio; Kostiuk, I; Jans, E.; Greeven, L. M.; Geertsema, R. E.; Pellegrino, A.; Gabriel, E.; Merk, M.; Butter, J. S.; Koppenburg, P.; Soares, M. Senghi; Akiba, K. Carvalho; Klaver, S.; Gras, C. Sanchez; Raven, G.; Sole, S. Ferreres; Schubiger, M.; Hulsbergen, W.] Nikhef Natl Inst Subatom Phys, Amsterdam, Netherlands.;[Massafferri, A.; Cruz Torres, M.; De Miranda, J. M.; Machado, D. Torres; Gomes, A.; dos Reis, A. C.; Bediaga, I; Baptista Leite, J.] Ctr Brasileiro Pesquisas Fis CBPF, Rio De Janeiro, Brazil.;[Lopes, J. H.; Polycarpo, E.; Souza De Paula, B.; Souza De Almeida, F. L.; Gandelman, M.; Rangel, M. S.; Ferreira Rodrigues, F.; Hicheur, A.; Nasteva, I; Otalora Goicochea, J. M.; De Paula, L.; Amato, S.; Meyer Garcia, L.] Univ Fed Rio de Janeiro UFRJ, Rio De Janeiro, Brazil.;[Yang, Z.; Jiang, F.; Fan, J.; Wang, Z.; Qin, N.; Ren, Z.; Xu, L.; Wang, J.; Hu, X.; Wang, M.; Gu, C.; Gong, G.; Kang, Y.; Chen, C.; Zhu, X.; Luo, Y.; Yang, D.; Mu, H.; Zeng, M.; Qi, H.; Zhang, L.; Gan, Y.] Tsinghua Univ, Ctr High Energy Phys, Beijing 100084, Peoples R China.;[Lu, Y.; Li, Y.; Ma, L.; Wang, J.; Carli, I; Chen, S.; Tobin, M.; Zou, Q.; Liu, S.] Inst High Energy Phys IHEP, Beijing 100039, Peoples R China.
关键词：
charmed baryons;limits on production of particles;charmed quarks;experimental tests
摘要：
A search for the doubly charmed baryon Ω
+
with the decay mode Ω
+
→ Ξ
+
K−π+ is performed using proton-proton collision data at a centre-of-mass energy of 13 TeV collected by the LHCb experiment from 2016 to 2018, corresponding to an integrated luminosity of 5.4 fb−1. No significant signal is observed within the invariant mass range of 3.6 to 4.0GeV/c2. Upper limits are set on the ratio R of the production cross-section times the total branching fraction of the Ω
+
→ Ξ
+
K−π+ decay with respect to the
$$\Xi _{cc}^{ + + } \to \Lambda _c^ + {K^ - }{\pi ^ + }{\pi ^ + }$$
decay. Upper limits at 95% credibility level for R in the range 0.005 to 0.11 are obtained for different hypotheses on the Ω
+
mass and lifetime in the rapidity range from 2.0 to 4.5 and transverse momentum range from 4 to 15 GeV/c.
摘要：
Iterative methods are used to simulate the in vitro feedforward neural networks in physiological experiments. Emissivity can be propagated to a minimum of ten groups. However, the discharge activity of each group will be more synchronized. The feedforward neural networks have a wide range of applications in machine learning, and the weight of synapses considerably influences the propagation of weak signals. Herein, we investigated the effect of Gaussian colored noise and electromagnetic radiation on the propagation of the subthreshold excitatory postsynaptic current signals in the input layer of the multilayer Izhikevich neural feedforward networks. In the absence of electromagnetic radiation, the excitatory postsynaptic current signal is stably propagated and amplified in multilayer feedforward neural networks under the optimal Gaussian colored noise strength or correlation time in the output layer of the network. Compared with the case in which there is no electromagnetic radiation, the presence of electromagnetic radiation slightly reduces the propagation of weak signals. Further, the time required to propagate the excitatory postsynaptic current signal to the output layer increases with the increasing feedback gain. The feedforward neural network considered in this study is a considerably simple model. More complex structures, such as backward connection and delayed feedback, can be observed in real biological systems. Hence, the next step will be to study more complex neural models with neuron models based on the physiological experimental data and compare them with real biological systems. Furthermore, the study of neural networks can be combined with an experimental study about the auditory nervous system of bats to understand the biological mechanism associated with the auditory system function of bats from two perspectives.
作者机构：
[Yu, Yun-Wei] Cent China Normal Univ, Inst Astrophys, Wuhan 430079, Peoples R China.;Cent China Normal Univ, Minist Educ, Key Lab Quark & Lepton Phys, Wuhan 430079, Peoples R China.
通讯机构：
[Yu, Yun-Wei] C;Cent China Normal Univ, Inst Astrophys, Wuhan 430079, Peoples R China.
摘要：
Modern wide-field high-cadence surveys have revealed the significant diversity of optical transient phenomena in their luminosity and timescale distributions, which led to the discovery of some mysterious fast optical transients (FOTs). These FOTs can usually rise and decline remarkably in a timescale of a few days to weeks, which are obviously much rapider than ordinary supernovae. SN 2019bkc/ATLAS19dqr is one of the fastest detected FOTs so far and, meanwhile, it was found to be un-associated with a host galaxy. These discoveries provide a good chance to explore the possible origins of FOTs. So, we model the light curves of SN 2019bkc in details. It is found that SN 2019bkc can be well explained by the thermal emission of an explosion ejecta that is powered by a long-lasting central engine. The engine could be a spinning-down millisecond magnetar or a fallback accretion onto a compact object. Combining the engine property, the mass of the ejecta, and the hostlessness of SN 2019bkc, we suggest that this FOT is likely to originate from a merger of a white dwarf and a neutron star.
