Energy deposition, alternative

Better control of the cantilever oscillation in liquid environment can be achieved when the cantilever is oscillated directly by an external force. This idea was implemented by the so-called Magnetic-Alternative-Current Mode (MAC Mode) [194]. A magnetic cantilever is driven by an external magnetic field which is generated by a solenoid placed beneath the sample. The direct excitation of the cantilever avoids unwanted resonance s from the cantilever holder, the fluid body, and the sample itself. Furthermore, the improved signal-to-noise ratio allows smaller oscillation amplitudes and set point ratios Asp/Af closer to 1. Both factors result in a significant reduction in the energy deposited into the sample,... 

The effective P may be determined with the electron beam apparatus. When the sample (slab geometry) is thick enough to absorb all of the incident electrons, a compressive stress wave propagates from the irradiated region into the sample bulk. A transducer, located just beyond the deposition depth, may be used to record the stress pulse. Alternatively, the displacement or velocity of the rear surface of sample may be observed optically and used to infer the initial pressure distribution from the experimentally measured stress history. Knowledge of the energy-deposition profile then permits the determination of the Gruneisen coefficient. 

The neutral beam density in the interaction region can be determined from a measurement of the energy deposited by the fast neutral beam into a pyroelectric crystal whose response is first calibrated by a well-characterized ion beam, as discussed by Wetzel et al. (1987). As an alternative, the well-established Kr or Ar absolute ionization cross sections (known to better than 5%) can be used to calibrate the pyroelectric crystal. The calibrated detector is then used to determine the flux of the neutral target beam in absolute terms. This procedure avoids the frequent and prolonged exposure of the delicate pyroelectric crystal to fairly intense ion beams (Freund et al., 1990 Tamovsky and Becker, 1992). 

Physics of energy deposition Induction of oscillations in water molecules by propagating electromagnetic waves Resistive heating hy electrical alternating current... 

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