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To tackle problems that can not be solved by current digital computers, many systems propose ideas from physics and neuroscience. The CTDS solver introduced by Ercsey-Ravasz and Toroczkai is one of such system. It solves the satisfiability problem by reducing it to a minimization of a time-varying target function. Although the possibility of an efficient electric circuit implementation of the solver has been shown, in terms of physical realizations, the solver has a problem of unbounded variations of the target function parameters. Here we propose a variant of the solver with bounded target function parameters. It includes several possible modifications of the solver in system parameter differences. We also show the basic characteristics of the solver, the upper and lower bounds of the target function parameters. 

To tackle problems that can not be solved by current digital computers, many systems propose ideas from physics and neuroscience. The CTDS solver introduced by Ercsey-Ravasz and Toroczkai is one of such system. It solves the satisfiability problem by reducing it to a minimization of a time-varying target function. Although the possibility of an efficient electric circuit implementation of the solver has been shown, in terms of physical realizations, the solver has a problem of unbounded variations of the target function parameters. Here we propose a variant of the solver with bounded target function parameters. It includes several possible modifications of the solver in system parameter differences. We also show the basic characteristics of the solver, the upper and lower bounds of the target function parameters. 

Theβ-delayed neutron-emission probabilities of 28 exotic neutron-rich isotopes of Pm, Sm, Eu, and Gd were measured for the first time at RIKEN Nishina Center using the Advanced Implantation Detector Array (AIDA) and the BRIKEN neutron detector array. The existingβ-decay half-life (T_1/2) database was significantly increased toward more neutron-rich isotopes, and uncertainties for previously measured values were decreased. The new data not only constrain the theoretical predictions of half-lives andβ-delayed neutron-emission probabilities, but also allow for probing the mechanisms of formation of the high-mass wing of the rare-earth peak located atA≈ 160 in ther-process abundance distribution through astrophysical reaction network calculations. An uncertainty quantification of the calculated abundance patterns with the new data shows a reduction of the uncertainty in the rare-earth peak region. The newly introduced variance-based sensitivity analysis method offers valuable insight into the influence of important nuclear physics inputs on the calculated abundance patterns. The analysis has identified the half-lives of¹⁶⁸Sm and of several gadolinium isotopes as some of the key variables among the current experimental data to understand the remaining abundance uncertainty atA= 167–172.

 

Abstract We report on multiwavelength target-of-opportunity observations of the blazar PKS 0735+178, located 2.°2 away from the best-fit position of the IceCube neutrino event IceCube-211208A detected on 2021 December 8. The source was in a high-flux state in the optical, ultraviolet, X-ray, and GeV γ -ray bands around the time of the neutrino event, exhibiting daily variability in the soft X-ray flux. The X-ray data from Swift-XRT and NuSTAR characterize the transition between the low-energy and high-energy components of the broadband spectral energy distribution (SED), and the γ -ray data from Fermi-LAT, VERITAS, and H.E.S.S. require a spectral cutoff near 100 GeV. Both the X-ray and γ -ray measurements provide strong constraints on the leptonic and hadronic models. We analytically explore a synchrotron self-Compton model, an external Compton model, and a lepto-hadronic model. Models that are entirely based on internal photon fields face serious difficulties in matching the observed SED. The existence of an external photon field in the source would instead explain the observed γ -ray spectral cutoff in both the leptonic and lepto-hadronic models and allow a proton jet power that marginally agrees with the Eddington limit in the lepto-hadronic model. We show a numerical lepto-hadronic model with external target photons that reproduces the observed SED and is reasonably consistent with the neutrino event despite requiring a high jet power.