Magnetic decelerator

Narevicius E, Raizen MG (2012) Toward cold chemistry with magnetically decelerated supersonic beams. Chem Rev 112 4879... 

Dunkle notes (Ref 15) that one of the recent works described a deceleration of the detonation wave in oxy-acetylene mixtures by crossed electric and magnetic fields, which makes an interesting comparison with the acceleration of the shock wave in argon electrically as reported by R.M. Parrick ... 

In a guided ion beam experiment, reactant ions are created in the source region, mass selected by a mass spectrometer (a magnetic sector in our instruments), decelerated to a desired kinetic energy, and injected into a radiofrequency (rf) octopole ion beam guide [10,11]. This device comprises eight rods cylindrically surrounding the ion beam path. Opposite phases of an rf potential... 

Fig. 15 General layout of MSIB technique (l-ion source, M-analysis magnet, A-acceleration or deceleration stage and T-target chamber).

A further less commonly employed but very classical method for mass-selection is the Wien-filter which combines an electrostatic and a magnetic field for mass-selective cluster deflection. This device is applied in particular with the purpose to obtain large cluster currents for cluster-surface interaction and deposition experiments at moderate resolution [75, 76]. Another approach for size-selection in combination with a sputter source ]47] or a laser vaporization source [61,77,78] has been chosen recently. In both cases, a magnetic dipole field has achieved the size-selection. Subsequent deceleration of the size-selected clusters to less than 1 eV per atom enables soft-landing under UHV conditions [47]. Monodispersed chromium cluster beam densities range from 0.1 to 5nA mm, depending on the cluster size ]47]. 

Fig. 1.33. Setup used by Smalley and coworkers to inject cluster ions into an ICR cell. The cluster beam is steered and focused by deflection plates and two Einzel lenses. Before entering the ICR cell, the cluster ions are decelerated. The inset shows the principle of an ICR mass spectrometer. Ions are excited by an rf-pulse to propagate in circular orbits. The image currents induced in the electrode plates are amplified and analyzed through computer-based Fourier transformation. The magnetic field in this scheme is perpendicular to the drawing plane. The schemes have been adopted from [71,177,178]...

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