Beam apparatus, schematic diagram

In essence, a guided-ion beam is a double mass spectrometer. Figure A3.5.9 shows a schematic diagram of a griided-ion beam apparatus [104]. Ions are created and extracted from an ion source. Many types of source have been used and the choice depends upon the application. Combining a flow tube such as that described in this chapter has proven to be versatile and it ensures the ions are thennalized [105]. After extraction, the ions are mass selected. Many types of mass spectrometer can be used a Wien ExB filter is shown. The ions are then injected into an octopole ion trap. The octopole consists of eight parallel rods arranged on a circle. An RF... 

The apparatus consists of a pulsed molecular beam, a pulsed ultraviolet (UV) photolysis laser beam, a pulsed vacuum ultraviolet (VUV) probe laser beam, a mass spectrometer, and a two-dimensional ion detector. The schematic diagram is shown in Fig. 1. 

Fig. 3. Schematic diagram of the Northwestern apparatus for IR laser kinetic measurements in the gas phase. D, and D2 are InSb detectors with D2 being a high speed photovoltaic detector. M = Mirror, I = iris, C = chopper, BS = beam splitter, P = photolysis cell. [Reproduced with permission from Ouderkirk et al. (75).]...

Fig. 6. Schematic diagram of the Nottingham apparatus for IR kinetic measurements on solutions. Solid lines represent the light path, broken lines the electrical connections. L = Line tunable CO laser, S = sample cell, F = flash lamp, P = photodiode, D = fast MCT IR detector, T = transient digitizer, O = oscilloscope, and M = microcomputer. Nonfocussing optics were used throughout, and the IR laser beam was heavily attenuated by a variable path cell V, filled with liquid methanol, placed immediately in front of the detector. [Reproduced with permission from Moore et al. (61).]...

The technique used to acquire the data in this paper was SNIFTIRS. A schematic diagram of the required apparatus is shown in Figure 5, and has been described in detail elsewhere. The FTIR spectrometer used was a vacuum bench Bruker IBM Model IR/98, modified so that the optical beam was brought upwards through the sample compartment and made to reflect from the bottom of the horizontal mercury surface. The methods used herein are adapted from a configuration that has been used by Bewick and co-workers (21) at Southampton. 

A schematic diagram of the apparatus used in the energy transfer experiments is shown in Figure 8.22. The particles are produced and levitated in an electrodynamic levitator as described previously. Excitation is provided by the filtered output of either a Xe or Hg-Xe high-pressure arc. The intensity produced at the particle was found to be 10-50 mW/cm2. The fluorescence emitted from each of the levitated particles was monitored at 90° to the exciting beam using //3 optics, dispersed with a j-m monochromator, and detected with an optical multichannel analyzer. The levitator could be... 

The mass spectrometric determination of ions from the field microscope has already been mentioned (13a). Figure 10 shows a schematic diagram of the apparatus. A small fraction of the ion beam is permitted to penetrate through a 30-mil hole in the screen of a field emission tube into a sensitive mass spectrometer. Electron emission in high vacuum... 

Figure 5. Schematic diagram of crossed ion-neutral beam apparatus.53...

Fig. 13.1 Schematic diagram of apparatus IS, ion source O, atomic beam oven F, Faraday cup EM, electron multiplier HW, hot-wire detector. Long and short dashed line, ion beam solid line, Na beam dashed lines, laser beams (from ref. 1).

Schematic diagram of the velocity selector in a molecular beam apparatus.

Figure 7.2. Schematic diagram of the static mercury vapour apparatus. A Absorption cell B metal support C PTFE tubing D reduction vessel E silicone rubber F magnetic bar G magnetic stirrer H PTFE tubing Iq incident beam intensity I transmitted beam intensity and J exhaust. From [34]...

Figure 1. Schematic diagram of the apparatus. The laser system which produces a 1.06 pm ultra-short pulse and its 353 nm third harmonic is not shown. F denotes filter L, lens CC, continuum generation cell D, diffusing plate CL, cylindrical lens S, spectrograph slit G, concave grating FP, focal plane DC, detector controller. 10 and 1 label the continuum beams passing through...

Fig. 2. Schematic diagram of the apparatus. The superconducting magnetic coils create trapping potential that confines atoms near the focus of the 243 nm laser beam. The beam is focused to a 50 pm waist radius and retro-reflected to allow for Doppler-free excitation. After excitation, fluorescence is induced by an applied electric field. A small fraction of the 122 nm fluorescence photons are counted on a microchannel plate detector. Not shown is the trapping cell which surrounds the sample and is thermally anchored to a dilution refrigerator. The actual trap is longer and narrower than indicated in the diagram...

Fig. 2 A schematic diagram of the fast-atomic beam apparatus used in this measurement...

In our small-angle x-ray scattering studies of coals, x-rays (wavelength 1.54A) from a copper-target diffraction tube were formed into a well-defined beam and struck the coal sample, which was in powdered form and which had a thickness of about 1 mm. Figure 1 shows a schematic diagram of the scattering apparatus. 

As the name suggests, electric resonance experiments make use of electric fields to achieve molecular state selection. Figure 8.25 shows a schematic diagram of a molecular beam electric resonance instrument, which we will discuss in more detail when we describe experiments on the CsF molecule. In contrast to the magnetic resonance apparatus discussed earlier, the A, B and C fields in figure 8.25 are all electric fields. In... 

Figure 3.6-10 Schematic diagram of a femtosecond time-resolved CARS apparatus. YAG, cw mode-locked Nd YAG laser ML, mode locker PL, polarizer A s, apertures LP, laser pot DM, dichroic mirror DLl, femtosecond dye laser SA, saturable absorber CLFB, cavity-length feedback system DL2, picosecond dye laser W, tuning wedge E, etalon FD, fixed delay VD, variable delay BS, beam splitter P s, half-wave plates (when necessary) F s, filters S, sample MC, monochromator PMT, cooled photomultiplier. (Okamoto and Yoshihara, 1990).

Figure 1. A schematic diagram of the pulsed cluster beam apparatus.

Figure 4 shows a schematic diagram of an ultrahigh vacuum (5 x 10 ° Torr) apparatus that integrates LEED, XPS, TPD, LEISS, and electrochemistiy (EC). The base pressure of the chamber is 5 x 10" Torr. The sample is mounted on a probe, a tube fabricated out of stainless steel, at the top of the chamber. The probe allows experiments to be performed at very low temperatures for example, the probe is filled with hquid nitrogen for experiments at 77 K. The sample can also be heated resistively (up to 1500 K) via copper wires attached to the sample for still higher temperatures, an electron beam from a tungsten wire located behind the sample is employed. Temperature is monitored via a ReAV-Re thermocouple. 

Figure 7. Schematic diagram of the supersonic beam apparatus which combines laser-induced fluorescence spectroscopy with time-of-flight mass spectrometry. Reproduced with permission from Ref [92a].

Figure 2. Schematic diagram of fluorescence lifetime determination apparatus. LI and L2 are lenses M, mirror BST, beam steerer BSP, beam splitter SCH, sample cell holder MONO, monochromator PMT, photomultiplier tube. Other components are described in text.

Figure 1 shows the schematic diagram of the experimental apparatus. The transversely excited atmospheric pressure CO2 pulse laser (LUMONICS TEA-841) was used as a light source. The laser beam was slightly converged by a ZnSe lens with a focal length of 1.5 m and introduced into a reaction cell. The reaction cell was a cylindrical stainless steel tube, 2000 mm long x 54.6 mm inner diameter, equipped with NaCl windows at both ends. The wavenumber of the laser was set... 

Fig. 1. Schematic diagram of a crossed molecular beam apparatus. (1) primary beam oven. (2) velocity selector. (3) secondary beam oven. (4) velocity analyser for the secondary beam, (5) detector for measuring the differential cross section, (6) monitor detector. (7) detector for measuring the total cross section.

A schematic diagram of the apparatus for static and dynamic light scattering is shown in Figure 1 (top view). The initial laser beam passes horizontally through the sample and defines the wavevector k,. Scattered light is detected by a detection unit, which rotates in a horizontal plane. The position of the... 

Figure 14. Schematic diagram of the CO metastable TOF experimental apparatus is shown. The molecular beam (MB) containing 10% ketene in neon or helium can be placed at any acute angle (0,ab) relative to the flight path, and it is collimated by an electroformed skimmer (not shown). The photolysis laser is an unpolarized excimer (XeCl or XeF), and the probe laser is a pulse dye amplification system whose polarization can be made either parallel (sPR, ) or perpendicular (e ) to the flight path. The metastables pass through a 1-cm orifice and deflector plates and grids (both not shown), and they strike a heated Ni surface. Electrons produced from the Ni surface by the metastables are steered by a plate set at —1500 V onto a stack of 3 MCPs the resulting pulses are then amplified, discriminated against noise from dark current, and counted by a multichannel scaler.

Fig. 13. Schematic diagram of molecular beam apparatus used to study the total cross-section for the process H + Br2 ->HB + H.

Fig. 1. Schematic diagram of the fast-neutial-beam apparatus.

Fig. 6. Schematic diagram of a two-beam apparatus to study H2 formation on grains. Separate beams of H and D atoms are produced in an RF source, with about 70 to 85% dissociation of the feed H2 and D2 gases. The collimated, differentially pumped thermal-energy beams of H and D atoms are brought to the ultrahigh-vacuum scattering chamber, where they are adsorbed onto a grain sample (olivine, pyrolitic graphite, etc.). The HD and D2 produced on the surface are desorbed using temperature-programmed desorption (TPD) and are detected by the quadrupole mass selector (QMS) (Vidali et al, 1998).

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