Effects of anomalous magnetic moment and temperature on pair production in an external magnetic field

1981 ◽  
Vol 30 (13) ◽  
pp. 399-402 ◽  
Author(s):  
W. Dittrich ◽  
W. Bauhoff
1990 ◽  
Vol 142 ◽  
pp. 35-38
Author(s):  
V.N. Oraevsky ◽  
V.B. Semikoz

Neutrinos interacting with the vacuum of vector bosons and leptons possess important vacuum electromagnetic characteristics: viz., the anomalous magnetic moment Δμvacν and the mean-square radius of charge distribution <r2>1/2. As a result, neutrinos, just like neutrons, may interact with an external magnetic field.


2018 ◽  
Vol 27 (02) ◽  
pp. 1850011
Author(s):  
Zeinab Rezaei

In this work, we calculate the neutron anomalous magnetic moment (AMM) supposing that this value can depend on the density and magnetic field of the system. We employ the lowest-order constraint variation (LOCV) method and [Formula: see text] nuclear potential to calculate the medium dependency of the neutron AMM. It is confirmed that the neutron AMM increases by increasing the density, while it decreases as the magnetic field grows. The energy and equation of state for the system have also been investigated.


1976 ◽  
Vol 15 (5) ◽  
pp. 149-152 ◽  
Author(s):  
V. N. Baier ◽  
V. M. Katkov ◽  
V. M. Strakhovenko

2021 ◽  
Vol 44 (3) ◽  
Author(s):  
Sarah Mohammadinejad ◽  
Damien Faivre ◽  
Stefan Klumpp

AbstractThe swimming of bacteria provides insight into propulsion and steering under the conditions of low-Reynolds number hydrodynamics. Here we address the magnetically steered swimming of magnetotactic bacteria. We use Stokesian dynamics simulations to study the swimming of single-flagellated magnetotactic bacteria (MTB) in an external magnetic field. Our model MTB consists of a spherical cell body equipped with a magnetic dipole moment and a helical flagellum rotated by a rotary motor. The elasticity of the flagellum as well as magnetic and hydrodynamic interactions is taken into account in this model. We characterized how the swimming velocity is dependent on parameters of the model. We then studied the U-turn motion after a field reversal and found two regimes for weak and strong fields and, correspondingly, two characteristic time scales. In the two regimes, the U-turn time is dominated by the turning of the cell body and its magnetic moment or the turning of the flagellum, respectively. In the regime for weak fields, where turning is dominated by the magnetic relaxation, the U-turn time is approximately in agreement with a theoretical model based on torque balance. In the strong-field regime, strong deformations of the flagellum are observed. We further simulated the swimming of a bacterium with a magnetic moment that is inclined relative to the flagellar axis. This scenario leads to intriguing double helical trajectories that we characterize as functions of the magnetic moment inclination and the magnetic field. For small inclination angles ($$\lesssim {20^{\circ }}$$≲20∘) and typical field strengths, the inclination of the magnetic moment has only a minor effect on the swimming of MTB in an external magnetic field. Large inclination angles result in a strong reduction in the velocity in direction of the magnetic field, consistent with recent observations that bacteria with large inclination angles use a different propulsion mechanism.Graphic abstract


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