Beta electron, kinetic energy

The amount of energy lost by the beta particle depends upon both its distance of approach to the electron and its kinetic energy. Beta particles and orbital electrons have the same mass therefore, they are easily deflected by collision. Because of this fact, the beta particle follows a tortuous path as it passes through absorbing material. The specific ionization of a beta particle is low due to its small mass, small charge, and relatively high speed of travel. 

Write balanced nuclear equations for beta decay, positron emission, electron capture, and alpha decay processes and calculate the maximum kinetic energies of particles emitted (Section 19.2, Problems 7-18). 

Technetium (Tc Z = 43) is a synthetic element used as a radioactive tracer in medical studies. A Tc atom emits a beta particle (electron) with a kinetic energy (Ek) of 4.71 X10 J. What is the de Broglie wavelength of this electron (f =... 

The neutrino and antineutrino groups carry somewhat more than half of the decay energy, while the beta-particle group carries somewhat less than half. The kinetic energy of the product nuclide is very small because of the several-thousandfold smaller beta-particle mass. This recoil energy, in the range of a few electron volts, nevertheless may cause chemical change such as displacement of an atom from a crystal lattice. 

One important feature of the positron interaction with matter is the formation of the positronium, which is the bound state of an electron and a positron. We have found that the presence of various types of surfactant aggregates, such as micelles, leads to a reduction of (thermalized) positronium formation and suggested (24) that trapping of energetic positrons (or positronium atoms possessing excess kinetic energies) by the surfactant aggregates is responsible for the reduced formation of thermalized positronium. Because of the similarity of the species, positron and electron, particle and anti-particle, one could postulate that the behavior of the positron in liquid scintillator solutions would resemble very much that of the beta particle (e ). 

The kinetic energy of the emitted electron (the beta ray) has been measured by use of a magnetic beta-ray spectrometer (measurement of the curvature of the path of the beta ray in a magnetic field) and found to be 1.32 MeV. The mass of Ca, which is stable and constitutes 97% of natural calcium, is 39.96259 d, as determined with the mass spectrograph. What is the mass of K ... 

Walla, P. J., Linden, P. A., Ohta, K., and Eleming, G. R. 2002. Excited-state kinetics of the carotenoid S-1 state in LHC n and two-photon excitation spectra of Intein and beta-carotene in solution Efficient car S-1 -> Chi electronic energy transfer via hot S-1 states J. Phys. Chem. A 106 1909-16. 

Radioactivity is the spontaneous emission of radiation from an unstable nucleus. Alpha (a) radiation consists of helium nuclei, small particles containing two protons and two neutrons (fHe). Beta (p) radiation consists of electrons ( e), and gamma (y) radiation consists of high-energy photons that have no mass. Positron emission is the conversion of a proton in the nucleus into a neutron plus an ejected positron, e or /3+, a particle that has the same mass as an electron but an opposite charge. Electron capture is the capture of an inner-shell electron by a proton in the nucleus. The process is accompanied by the emission of y rays and results in the conversion of a proton in the nucleus into a neutron. Every element in the periodic table has at least one radioactive isotope, or radioisotope. Radioactive decay is characterized kinetically by a first-order decay constant and by a half-life, h/2, the time required for the... 

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