相关论文: The radiative capture reaction rate from $\Lambda …
We compare numerical methods for solving the radiative transfer equation in the context of the photoionization of intergalactic gaseous hydrogen and helium by a central radiating source. Direct integration of the radiative transfer equation…
In this paper we address the indirect method, which can provide a powerful technique to obtain information about radiative capture reactions at astrophysically relevant energies. The idea of the indirect method is to use the indirect…
We have calculated the rate coefficients for D(1s) + H^+ <--> D^+ + H(1s) using recently published theoretical cross sections. We present results for temperatures T from 1 K to 2x10^5 K and provide fits to our data for use in plasma…
Hagedorn states (HS) are a tool to model the hadronization process which occurs in the phase transition phase between the quark gluon plasma (QGP) and the hadron resonance gas (HRG). Their abundance is believed to appear near the Hagedorn…
We investigate bounds on speed, non-adiabatic entropy production and trade-off relation between them for classical stochastic processes with time-independent transition rates. Our results show that the time required to evolve from an…
Non-local energy transfer between bound electronic states close to the ionisation threshold is employed for efficient state preparation in dilute atom systems from technological foundations to quantum computing. The generalisation to…
The ion-molecule reactions $\text{D}_2^++\text{NH}_3$ and $\text{D}_2^++\text{ND}_3$ are studied at low collision energies ($E_{\text{coll}}$ from zero to $\sim k_\textrm{B}\cdot 50\,\text{K}$), with the $\text{D}_2^+$ ions in the ground…
The HeH$^+$ cation undergoes dissociative recombination with a free electron to produce neutral He and H fragments. We present calculations using ab initio quantum defects and Fano's rovibrational frame transformation technique, along with…
We present measurements of trapped-ion motional-state heating rates in niobium and gold surface-electrode ion traps over a range of trap-electrode temperatures from approximately 4 K to room temperature (295 K) in a single apparatus. Using…
We introduce a propagation-based approach to thermal state simulation by adapting Pauli and Majorana propagation to imaginary-time evolution in the Schr\"odinger picture. Our key observation is that high-temperature states can be sparse in…
We present a time-dependent radiative model of the atmosphere of HD209458b and investigate its thermal structure and chemical composition. In a first step, the stellar heating profile and radiative timescales were calculated under…
The cross section and rate constants for the title reaction are calculated for all the spin-orbit states of N$^+$($^3P_{J_A}$) using two statistical approaches, one purely adiabatic and the other one mixing quantum capture for the entrance…
Discrete gamma-rays from the neutron capture state of 13C to its low-lying bound states have been measured using pulsed neutrons at En = 550 keV. The partial capture cross sections have been determined to be 1.7+/-0.5, 24.2+/-1.0, 2.0+/-0.4…
Neutral hydrogen 21 cm transition is a useful tracer of the neutral interstellar medium. However, inferring physical condition from the observed 21 cm absorption and/or emission spectra is often not straightforward. One complication in…
The cross section for radiative thermal neutron capture on ${}^{3}He$ ($\He3 +n \to \He4 +\gamma$; known as the $hen$ reaction) is calculated based on heavy-baryon chiral perturbation theory. The relevant M1 operators are derived up to…
A general method for the direct evaluation of the temperature dependence of the quantum-mechanical reaction rate constant in many-dimensional systems is described. The method is based on the quantum instanton approximation for the rate…
Using the Brink-Axel hypothesis we derive the rate $R$ for nuclear dipole excitation by a laser pulse carrying $N \gg 1$ photons with average energy $\hbar \omega_0 \approx 5$ MeV. As expected $R \propto (\hbar \omega_0)^3$. The rate is…
We develop a method to compute the sphaleron rate in the electroweak broken phase nonperturbatively. The rate is somewhat slower than a perturbative estimate. In SU(2) X U(1) Higgs theory at the physical value of Theta_W, and assuming that…
Long-range interacting systems such as nitrogen vacancy centers in diamond and trapped ions serve as useful experimental setups to probe a range of nonequilibrium many-body phenomena. In particular, via driving, various effective…
Radiative capture reaction rates for $^6$He, $^9$Be and $^{17}$Ne formation at astrophysical conditions are studied within a three-body model using the analytical transformed harmonic oscillator method to calculate their states. An…