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Gas Chromatography
Published in Grinberg Nelu, Rodriguez Sonia, Ewing’s Analytical Instrumentation Handbook, Fourth Edition, 2019
Yuwen Wang, Mochammad Yuwono, Gunawan Indrayanto
Ions move in a circular path in a magnetic field. The cyclotron frequency, ω, of the ion’s circular motion is mass dependent. By measuring the cyclotron frequency, the mass of an ion can be determined. From the Lorentz force law, the magnetic field applies a force evB, which must be equal to the centripetal force as the ion moves in an arc through the magnetic sector. evB=mv2r
C
Published in Splinter Robert, Illustrated Encyclopedia of Applied and Engineering Physics, 2017
[atomic, nuclear] Particle accelerator. Charged particles are released from the center of a circular accelerator and gain velocity with increasing radius (spiral path) as a result of an applied magnetic field. The cyclotron is used to investigate the structure of atomic nuclei and create new elements. The cyclotron was invented by Ernest Orlando Lawrence (1901–1958) in the 1920s, and was not feasible for practical use until a large enough magnetic field could be generated in the 1930s. Cyclotrons range in size from less than a meter to several meters. The largest cyclotron is the RIKEN in Japan, with a diameter of 19 m, 8 m high, and can operate with a maximum magnetic field strength of 3.8 T. The RIKEN cyclotron can reach 345 MeV of acceleration energy per atomic mass unit. The cyclotron designed by Ernest Lawrence was built in 1939 has a diameter of 1.52 m. A block-wave periodic magnetic field is applied that matches the resonance conditions to induce acceleration, based on the orbital period of the charge. The cyclotron frequency (angular velocity ωcyclotron; frequency νcycloton=ωcyclotron/2π) is a function of the applied magnetic field (B) and the magnitude of the charge (q) on the mass (m) as (ωcyclotron=qB/m see Figure C.93).
Continuum Emission Processes
Published in Ronald L. Snell, Stanley E. Kurtz, Jonathan M. Marr, Fundamentals of Radio Astronomy, 2019
Ronald L. Snell, Stanley E. Kurtz, Jonathan M. Marr
Note that the only variable in the cyclotron frequency expression is the magnetic field. All electrons in the same magnetic field, regardless of their velocities, will emit at the same frequency. Those moving at larger speeds will cycle around the magnetic field in larger circles, but complete the circle in the same amount of time.
Interaction of terahertz waves propagation in a homogeneous, magnetized, and collisional plasma slab
Published in Waves in Random and Complex Media, 2019
All these characteristics can also be obtained and are more obviously in Figure 5 for the right-hand polarization. Note that, the peak occurs in each sub-figure of Figure 5 and its width is also broadened with the magnetic field increases. These phenomena can be interpreted since the cyclotron frequency, , increases with the increase of the magnetic field. Therefore, there exists a wide range of the frequency band in which the incident wave could nearly be absorbed. This can be used as broadband absorption of terahertz waves propagation through the magnetic field and further be applied in the stealth technology. In addition, the incident angle has smaller impact on the absorbance of left-hand polarized terahertz wave than the absorbance of right-hand polarized terahertz wave. This phenomenon can be explained that the simplified permittivity of the plasma media for the left-hand polarized terahertz wave has smaller relationship with the incident angle.
Head-on collision of multi-solitons in a magnetized space dusty plasma in the presence of nonextensive polarization force
Published in Waves in Random and Complex Media, 2023
We consider magnetized polarized dusty plasma composed of negative dust, nonextensive ions and Maxwellian electrons to examine the head-on collision of DA multisolitons. The charge neutrality condition is , where for () are unperturbed number density, respectively. The dynamics of DAWs is characterized by the following normalized fluid equations: where is the dust density normalized by and by , and ϕ is the electrostatic wave potential normalized by, . The space and time variables are normalized by dust Debye radius and plasma frequency , respectively. The magnetic field is assumed to be along the z-axis (i.e. ), and the dust cyclotron frequency is the normalized by . Here, , and and . Here and R is polarization factor.
Aharonov–Bohm (AB) flux and thermomagnetic properties of Hellmann plus screened Kratzer potential as applied to diatomic molecules using Nikiforov–Uvarov-Functional-Analysis (NUFA) method
Published in Molecular Physics, 2022
I. B. Okon, C. A. Onate, E. Omugbe, U. S. Okorie, C. O. Edet, A. D. Antia, J. P. Araujo, C. N. Isonguyo, M. C. Onyeaju, E. S. William, R. Horchani, A. N. Ikot
The Hamiltonian operator of a charged particle [43] moving under the influence of the magnetic and Aharanov–Bohm flux fields in Schrodinger equation with HPSKP is given as Here, is the speed of light, represent the energy level while and represent the charge of the particle and the reduced mass, respectively. The vector potential can be written as the superposition of two terms such that is the vector potential with azimuthal components such that and , corresponding to the extra magnetic flux generated by a solenoid with and is the magnetic vector field accompanied by , . The vector potential can then be expressed as The Laplacian operator and the wave function in cylindrical coordinates is given as where represents the magnetic quantum number. Substituting Equations (20) and (21) into Equation (19) and simplifying gives rise to the Schrodinger-like equation where is an absolute value containing the flux quantum . The cyclotron frequency is represented by . Equation (22) is not exactly solvable due to the presence of the centrifugal barrier term . In order to solve Equation (22), we substitute the Greene–Aldrich approximation of the form to Equation (22) to deal with the inverse square term. Also, with the help of coordinate transformation , Equation (22) reduced to where