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We develop a well-posed multiparticle Coulomb scattering problem based on asymptotic solutions of a Coulomb multichannel scattering problem constructed in the adiabatic representation. A key feature of the studied problem is that the nonadiabatic channel coupling matrix is nontrivial at large internuclear distances. We consider the scattering problem in the case with an arbitrary momentum value and study solutions for small channel coupling matrix values in detail, constructing explicit representations for the asymptotic solution of the scattering problem.

2-Arachidonoylglycerol (2-AG) is acting as a full agonist of cannabinoid receptor 1 and 2. Direct manipulation of 2-AG levels is a challenging task. The amphiphilic properties and the instability of 2-AG in aqueous media complicate its use as a drug-like molecule. Additionally, inhibition of the protein machinery that regulates 2-AG levels may also affect other monoacylglycerols. Therefore, we developed a novel method to elevate 2-AG levels with a flash of light. The resulting tool is a photoactivatable "caged" 2-arachidonoylglycerol (cg2-AG) allowing for the rapid photorelease of the signaling lipid in live cells. We characterized the mechanism of uncaging and the effect of 2-AG on the regulation of the β-cell signaling network. After uncaging of 2-AG, we monitored calcium levels, CB1-GIRK channel coupling, and CB1-mediated inhibition of adenylate cyclase and protein kinase A activity.

This paper examined the fusion of 28Si with 90,96Zr-target by opting the energy dependent Woods-Saxon potential (EDWSP) model and code CCFULL. The CCFULL analysis suggested that for 28Si + 90Zr system, the vibrational excitations of 90Zr-isotope have been found to be very important while for 28Si + 96Zr system, in addition to multiphoton vibrational states of target, the considerations of nucleon transfer are essentially needed for the adequate addressal of the observed fusion data. In contrast, predictions based on EDWSP model appropriately recovered the fusion data of 28Si + 90,96Zr systems at sub-barrier realm. The EDWSP based results do not include various channel coupling effects explicitly but being the energy dependent nature of Woods-Saxon potential (WSP), the calculational results intrinsically incorporate the nuclear effects of the fusing systems. This unambiguously clarified that the energy dependent nature of the EDWSP generates analogous barrier modulations as emerged from the CCFULL analysis.

28 nm FD-SOI technology is electrically characterized aiming at cryogenic applications. Electrostatics and transport are evaluated and compared while lowering temperature from 300 K down to 4.2 K. FD-SOI versatility is shown over a wide temperature range of operation, as the back gate tuning efficiency is preserved at low temperatures. Insights on back gate bias behavior at room and low temperatures are obtained and the electrostatic coupling between front and back channels can be successfully modelled by using 1D Poisson-Schrodinger calculation from 300 K down to 4.2 K.

Inspired by the recent report of the exotic states $X_{0}(2900)$ and $X_{1}(2900)$ with four different quark flavors in the $D^{-}K^{+}$ invariant mass distributions of the decay process $B^{+}\rightarrow D^{+}D^{-}K^{+}$ by the LHCb collaboration, we systematically investigate the tetraquarks composed of $ud\bar{s}\bar{c}$ with meson-meson and diquark-antidiquark structures in the quark delocalization color screening model. We find that the $X_{0}(2900)$ can be interpreted as the molecular state $\bar{D^{*}}K^{*}$ with $IJ^{P}=00^{+}$. Moreover, two bound states are obtained by the channel coupling calculation, with energies $2341.2$ MeV for $IJ^{P}=00^{+}$ and $2489.7$ MeV for $IJ^{P}=01^{+}$, respectively. We also extend our study to the $uc\bar{d}\bar{s}$ systems and find that there is no any bound state, so the $D_{s0}(2317)$ cannot be identified as the $DK$ molecular state in present calculation. Besides, several resonance states with the diquark-antidiquark configuration are possible in both $ud\bar{s}\bar{c}$ and $uc\bar{d}\bar{s}$ systems. All these open charm bound states and resonances are worth searching in the future experiments., 8 pages, 2 figures. arXiv admin note: text overlap with arXiv:1902.05778

Author(s): Michaelides, Katerina; Hollings, Rory; Singer, Michael Bliss; Nichols, Mary H; Nearing, Mark A

A previously reported normally-off GaN double-channel (DC-) MOS-HEMT with a gate recess into the upper channel layer has achieved a remarkably low ${R}_{\text {on}}$ . In this letter, we found that the double-channel structure itself does not guarantee a low ${R}_{\text {on}}$ without careful consideration of the electrical coupling between the two channels. A strong channel-to-channel (C2C) coupling between the two channels is critical to reduce ${R}_{\text {on}}$ in the DC-MOS-HEMT by exploiting both channels at the access region while allowing currents to converge into the heterojunction lower channel at the gate region. Otherwise, with a weak C2C coupling, the conduction through the upper channel is comprised due to the high-resistivity MOS-channel section at the gate region. The fabricated DC-MOS-HEMT with C2C distance ( ${t}_{{\textsf {C2C}}}$ ) of 7.5 nm exhibits an appreciably lower ${R}_{\text {on}}$ than that with ${t}_{{\textsf {C2C}}} = \textsf {11.5}$ nm. Further analysis reveals the latter suffers from an increased sheet resistance at access region compared with the sheet resistance of the DC-heterostructure itself. A modified TLM characterization is proposed to analyze the C2C coupling in the DC-heterostructure. It is confirmed the DC-heterostructure with ${t}_{{\textsf {C2C}}} = \textsf {7.5}$ nm boasts a strong C2C coupling, while that with ${t}_{{\textsf {C2C}}} = \textsf {11.5}$ nm features relatively weak C2C coupling.

The formalism of the coupled $q\bar q$ and the $\varphi\varphi ( \pi-\pi$, $K\bar K, \pi K,...$) scalar channels is formulated, taking into account the ground and radial excited $q\bar q$ poles. The basic role is shown to be played by the transition coefficients $k^{(I)} (q\bar q, |\varphi\varphi)$, which are calculated using the quark-chiral Lagrangian without free parameters. The resulting method, called the pole projection mechanism (PPM), ensures: 1) one resonance for each $\varphi\varphi$ channel from the basic $q\bar q$ pole, e.g. the $f_0 (500)$ resonance in the $\pi\pi$ channel; 2) a possibility to have two $\varphi\varphi$ resonances, coupled to the same $q\bar q$ state, when the channel coupling is taken into account in the meson-meson channels, which yields $f_0 (500)$ and $f_0(980)$ from the same $n\bar n$ pole around 1 GeV; 3) the strong pole shift down for special ($\pi\pi, \pi K)$ channels due to large transition coefficients $k^{(I)}$, computed in this formalism without free parameters. The parameters of calculated complex poles are in reasonable agreement with the experimental data of the resonances $f_0(500)$, $f_0(980)$, $a_0(980)$, $a_0(1450)$, $K^*_0(700)$, $K^*_0(1430)$, $f_0(1370)$ and $f_0(1710)$., Comment: v2: 22 pages, 5 figures; new explanations are added, several important insertions are made, the list of references is enlarged

The coupled system was studied to investigate whether the inclusion of channel coupling is able to bind the system. We use a separable potential three-body model of the coupled system and a variational four-body calculation with realistic interactions. Our results exclude the possibility of a bound state by a large margin. Instead, we found a quasibound state above the threshold.

The dipion transitions ϒ(2S,3S,4S)→ϒ(1S,2S)ππ are systematically studied by considering the mechanisms of the hadronization of soft gluons, exchanging the bottomoniumlike Zb states, and the bottom-meson loops. The strong pion-pion final-state interaction, especially including the channel coupling to KK¯ in the S-wave, is taken into account in a model-independent way using the dispersion theory. Through fitting to the available experimental data, we extract values of the transition chromopolarizabilities |αϒ(mS)ϒ(nS)|, which measure the chromoelectric couplings of the bottomonia with soft gluons. It is found that the Zb exchange has a slight impact on the extracted chromopolarizablity values, and the obtained |αϒ(2S)ϒ(1S)| considering the Zb exchange is (0.29±0.20) GeV-3. Our results could be useful in studying the interactions of bottomonium with light hadrons.

The Chiral Confining Lagrangian, based on the chiral theory with quark degrees of freedom, is used to study the spectroscopy of scalar mesons. The formalism does not contain arbitrary fitting parameters and takes into account infinite number of transitions from meson-meson to quark-antiquark states. Starting from known $q\bar q$ poles the transition coefficients ensure the strong shift of the poles for the $\pi\pi$ and much smaller shift for the $K\bar K$ systems. The resulting amplitudes $f_{\pi\pi}$ and $f_{K\bar K}$ are calculated in terms of the $q\bar q$ and the free meson Green's functions. With the account of the $\pi\pi/K\bar{K}$ channel coupling one obtains two resonances: a wide resonance $E_1$ in the range 500-700 MeV and narrow $E_2 $ near 1 GeV, which can be associated with $f_0(500)$ and $f_0(980)$. A similar analysis, applied to the $I=1$ channel, shows that in this case two very close poles in different sheets appear near $E=980$ MeV, which can be associated with the $a_0 (980)$ resonance. The obtained $\pi\pi$ interaction amplitudes, $\operatorname{Re} f_{\pi\pi} (E)$ and $\operatorname{Im} f_{\pi\pi}(E)$ are compared with the known data., Comment: v5: 29 pages, 6 figures; version accepted to PRD, new equations with explanations are added, several important insertions are made, the list of references is correspondingly enlarged

Synopsis The effect of inner-shell excited channels on outer-shell photodetachment is investigated using a correlated and coupled-channel R-matrix method. The simplest multishell negative ion of Li− is treated near the 1s ionization threshold to determine strong”hole-state” continuum coupling with the direct photodetachment channels.

Two-channel and multichannel thermal unimolecular reactions are analyzed by simple models, starting with the calculation of separated-channel rate constants and accounting for intrinsic channel coupling afterward. Reactions with rigid- and with loose-activated complex channels are distinguished. Weak-collision, energy-transfer, effects are suggested to govern the competition between rigid-activated complex channels, while angular-momentum, “rotational channel switching”, effects dominate the competition between rigid- and loose-activated complex channels. The models are tested against master equation treatments of the dissociations of formaldehyde and of glyoxal from the literature. Besides giving insight into the influence of various molecular input parameters, the present approach leads to compact representations of rate constants suitable for inclusion in databases.

In the framework of the chiral quark model, we investigate the hidden strange pentaquark system of the Nϕ state with quantum numbers of IJP=1232−. The results show that the Nϕ state can be bound through the interaction of the σ meson exchange plus the effect of channel coupling, which means that the effect of channel coupling has an influence on the existence of this bound state.

The glue-like behavior of valence neutrons has been investigated in the Li isotopes. The 7Li nucleus is well known to be weakly bound system with the α + t cluster structure. By adding the valence neutrons, the reduction of the root-mean-square (RMS) radius of the proton density for the 7Li, 8Li and, 9Li nuclei is also well known from the viewpoint of the experimental data and theoretical approach. Elastic scattering cross sections of the Li isotopes on the 12C and 28Si targets at E/A ∼ 50 MeV are calculated. We find the change of the channel coupling (CC) effect on elastic scatterings of such Li isotopes by the glue-like role of the valence neutrons. Finally, we realize that the valence neutrons stabilize the binding of core parts, and the CC effect related the core excitation is indeed reduced., PROCEEDINGS OF THE 4TH INTERNATIONAL WORKSHOP ON “STATE OF THE ART IN NUCLEAR CLUSTER PHYSICS” (SOTANCP4), 13–18 May 2018, Texas, USA.

The specificity and universality of intracellular Ca2+ signals rely on the variety of spatio-temporal patterns that the Ca2+ concentration can display. Ca2+ liberation through inositol 1,4,5-trisphosphate receptors (IP3Rs) is key for this variety. In this paper, we study how the competition between buffers of different kinetics affects Ca2+ signals that involve Ca2+ release through IP3Rs. The study also provides insight into the underlying spatial distribution of the channels that participate in the signals. Previous works on the effects of Ca2+ buffers have drawn conclusions 'indirectly' by observing the Ca2+-bound dye distributions in the presence of varying concentrations of exogenous buffers and using simulations to interpret the results. In this paper, we make visible the invisible by observing the signals simultaneously with two dyes, Rhod-2 and Fluo-4, each of which plays the role of a slow or fast Ca2+ buffer, respectively. Our observations obtained for different concentrations of Fluo-4 highlight the dual role that fast buffers exert on the dynamics, either reducing the intracluster channel coupling or preventing channel inhibition and allowing the occurrence of relatively long cycles of Ca2+ release. Our experiments also show that signals with relatively high Ca2+ release rates remain localized in the presence of large Rhod-2 concentrations, while the mean speed of the elicited waves increases. We interpret this as a consequence of the more effective uncoupling between IP3R clusters as the slow dye concentration increases. Combining the analysis of the experiments with numerical simulations, we also conclude that Ca2+ release not only occurs within the close vicinity of the centers of the clearly identifiable release sites (IP3R clusters) but there are also functional IP3Rs in between them. Fil: Piegari, Estefanía. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; Argentina Fil: Lopez, Lucía Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; Argentina Fil: Ponce Dawson, Silvina Martha. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; Argentina

We present an analytical surface potential based model for the induced thermal noise at the gate terminal in High Electron Mobility Transistors, due to gate channel coupling. Our model is applicable to any HEMT device. We also present the results of the validation of our model with experimental data from literature.

Herein, we investigated the channel coupling (CC) effect on the elastic scatterings of lithium (Li) isotopes ($A =$ 6--9) for the $^{12}$C and $^{28}$Si targets at $E/A =$ 50--60 MeV. The wave functions of the Li isotopes were obtained using the stochastic multi-configuration mixing (SMCM) method based on the microscopic-cluster model. The proton radii of the $^{7}$Li, $^{8}$Li, and $^{9}$Li nuclei became smaller as the number of valence neutrons increased. The valence neutrons in the $^{8}$Li and $^{9}$Li nuclei exhibited a glue-like behavior, thereby attracting the $\alpha$ and $t$ clusters. Based on the transition densities derived from these microscopic wave functions, the elastic-scattering cross section was calculated using a microscopic coupled-channel (MCC) method with a complex $G$-matrix interaction. The existing experimental data for the elastic scatterings of the Li isotopes and $^{10}$Be nuclei were well reproduced. The Li isotope elastic cross sections were demonstrated for the $^{12}$C and $^{28}$Si targets at $E/A$ =53 MeV. The glue-like effect of the valence neutrons on the Li isotope was clearly demonstrated by the CC effect on elastic scattering. Finally, we realize that the valence neutrons stabilized the bindings of the core parts and the CC effect related to core excitation was indeed reduced., Comment: 21 pages, 9 figures, 2 tables, accepted in Physical Review C

Maneuvering of the fighter aerodynamic have certain requirements, this paper for needs of F-16 aircraft maneuvering, according to some existing fighter of the gas dynamic layout and parameters and establish more accurate fighter aerodynamic configuration, internal structure parameters and control input quantity. This paper also introduces the standard atmosphere model and the engine model, and analyzes the control characteristics of the aircraft by verifying the zero input response and channel coupling characteristics, and analyzes the performance of the model. This method can be applied to the performance analysis of other models.

This study focuses on using a semi-classical and quantum mechanical approach based originally on the theory of Winther and Alder that is used to explain the Coulomb excitation. This approach is called the coupled channels with continuum-discretised (CCCD), where the semi-classical and quantum models were used to investigate the channel coupling effects on the determination of the cross section for fusion σfus (mb) and the distribution of the fusion barrier Dfus (mb/MeV) for systems 14N+59Co, 16O+64Ni and 18O+64Ni. The comparison between the results of the semi-classical and quantum mechanical models along with the corresponding experimental data shows clearly that the adopted semi-classical model is very competitive to the quantum mechanical model and can be considered as efficient approach to study the properties of the fusion reactions.

This dual-ducted SUAV is a nonlinear and strong coupling of multiple-input and multiple-output system, and particularly between the pitch and roll channels channel coupling is strong, in order to implement effective control, it must be decoupled. The traditional methods are difficult to achieve effective control of the strong coupling of multivariable systems. For the SUAV model of nonlinear coupling characteristics, based on the establishment of the UAV attitude model, this paper designed an attitude ADRC decoupling controller. The simulation showed this ADRC decoupling controller had strong robustness and immunity, and solved the channels coupling between the pitch and roll.

[1] Decomposition of horizontally extended current system into components in the polarization processes and extraction of Cowling channel defined in the companion paper embedded in the total current system are numerically demonstrated. We successfully visualize the background and polarization components in the magnetosphere-ionosphere coupling process by using the proposed theoretical framework. As a fundamental response, the polarization charge produced by the Pedersen current divergence has a role to cancel and intensify the ambient background electric field inside and outside the high-conductivity band, respectively. In contrast, the polarization charge produced by the Hall current divergence has a role to rotate the electric field from the background electric field, which causes a meandering of ionospheric convection flow along the boundary of a high-conductivity band. The Hall and Pedersen currents are always perpendicular to each other. They never close each other when conductances are homogeneous, but they can do that at the conductivity gradient region. This is the reason why a Hall polarization charge is induced and a resultant Cowling channel is formed.

The character of riverbed sediments usually reflects fluvial processes and the dynamics of sediment transport in fluvial systems. The approach in this study was based on the measurement of the largest boulders located within a bankfull channel, and on the observation of changes in their size in the longitudinal profile of a headwater stream in the Moravian-Silesian Beskids Mountains. The resulting trends in a particle-size index reflect the character of sediment delivery into channel segments and the recent channel-forming processes. The largest boulders were observed in channel sections with a strong interaction of slope and fluvial processes, and a slight coarsening of sediments was recorded in the incised downstream sections of the longitudinal stream profile. In contrast, the refining of bed sediments was typical of the transitional zone between slope-channel coupled reaches and an alluvial cone characterised by a tendency to material aggradation.

The role of neutron transfer in fusion reactions of weakly-bound nuclei at subbarrier energies is studied within the empirical model of channel coupling. The results from calculating the fusion cross sections for the 7Li + 209Bi, 9, 11Li + 208, 206Pb, 6, 7, 9, 11Li + 152Sm reactions are presented. Good agreement with the available experimental data is shown. Several combinations of colliding nuclei for which the strong enhancement of subbarrier fusion due to the effect of neutron transfer processes are predicted.

We have analyzed the fusion excitation function data of various heavy ion systems in the near barrier energy region using Wongʼs formula and an energy dependent potential. The various channel coupling effects for different projectile–target combinations are properly mocked up by the energy dependent potential resulting in a very good agreement between the data and the predictions.

The three degree-of-freedom (3-DOF) laboratory helicopter is a typical multiple-input multiple-output system with high order, which has stronger channel coupling and higher non-linearity. The proposed controller is a combination of H2 control, H∞ control and multiple-model weighted control. The controller can be used to minimize the H2 performance index under the condition that H∞ performance index is smaller than a certain constant. In addition, the weights of multiple controllers in the multiple-model control can be adjusted in the real time in flight. In this way, not only can the whole system obtain the compromise between system performance and robust properties, but also the control precision and approximating precision are improved. Experimental results demonstrate the effectiveness of the proposed control strategy.

The role of neutron transfer is investigated in the fusion process near and below the Coulomb barrier within the empirical channel coupling approach. The possibility of neutron transfer with positive Q-values considerably increases the barrier penetrability. The enhancement of fusion cross sections for 58Ni + 64Ni, 32S + 64Ni, 40Ca + 48Ca, and 40Ca + 124Sn is well reproduced at subbarrier energies by the empirical channel coupling approach including the coupling to the neutron-transfer channels. The predictions of the fusion cross sections for several combinations of colliding nuclei are also proposed which may shed additional light on the effect of neutron transfer in fusion processes. A huge enhancement of deep subbarrier fusion probability was found for light neutron-rich weakly bound nuclei. This may be quite important for astrophysical primordial and supernova nucleosynthesis.

Okubo–Zweig–Iizuka-allowed partial decay widths, masses, and total decay width of charmonium states are studied in a nonrelativistic coupled-channel framework based on microscopic effective quark interactions. With the help of the complex scale transformation, the coupled channel equation is easily solved under the proper boundary condition for resonances. The obtained result as a whole is very successful and encouraging for the traditional charmonium states including ψ(4040) whose features of mass and partial decay widths have been argued historically. The coupling mechanisms of these states are investigated by reducing artificially the channel coupling strengths little by little and finally turning the coupling off. The situations turn out to be quite different from what we would have naively supposed. Other solutions than the traditional charmonium states were obatined at the same time. Some of them are discussed in relation with new particles observed recently.