Electron spectrometer, schematic diagram

Figure Bl.7.4. Schematic diagram of a reverse geometry (BE) magnetic sector mass spectrometer ion source (1) focusing lens (2) magnetic sector (3) field-free region (4) beam resolving slits (5) electrostatic sector (6) electron multiplier detector (7). Second field-free region components collision cells (8) and beam deflection electrodes (9).

Fig. 4.21. Schematic diagram of spectrometer arrangements for wavelength-dispersive and energy-dispersive X-ray spectroscopy (WDXS/EDXS) in electron microscopy.

Figure 7. Schematic diagram of a flowing-afterglow electron-ion experiment. The diameter of flow tubes is typically 5 to 10 cm and the length is 1 to 2 meters. The carrier gas (helium) enters through the discharge and flows with a velocity of 50 to 100 m/s towards the downstream end of the tube where it exits into a fast pump. Recombination occurs mainly in the region 10 to 20 cm downstream from the movable reagent inlet, at which the ions under study are produced by ion-molecule reactions. The Langmuir probe measures the variation of the electron density in that region. A differentially pumped mass spectrometer is used to determine which ion species are present in the plasma.

Figure 4.1 Schematic Diagram of an Electron-Impact Mass Spectrometer...

Figure 19.1. Schematic diagram of a general pump-probe-detect laser spectrometer suitable for picosecond electronic absorption, infrared (IR) absorption, Raman, optical calorimetry, and dichroism measurements. For picosecond fluorescence—a pump-detect method, no probe pulse needs to be generated.

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... 

The geometry of the experiment is shown in fig. 11.14. The axis of quantisation z is the direction of the light beam. The atomic sodium beam is incident in the x direction and the electron beam in the y direction. The schematic diagram also shows the 3px and 3py lobes of the target charge cloud for the 3pi substate. The scattering plane is the zy plane so that the component px of the recoil momentum p is observed in noncoplanar-symmetric kinematics. Because of the finite angular resolution of the spectrometer the components py and pz are of the order of 0.06 a.u. rather than zero. 

The farvitron, which is also a resonance spectrometer, was developed by Reich and Bachler from work by Tretner. A schematic diagram of this instrument is shown in Fig. 36 Electrons emitted from the filament (K) are accelerated by the grid W and ionize the gas inside electrode A. The ions formed are... 

Ionization and fragmentation produce a mixture of particles, some neutral and some positively charged. To understand what follows, we need to examine the design of an electron-impact mass spectrometer, shown in a schematic diagram in Figure 13.34. The sample is bombarded with 70-eV electrons, and the resulting positively charged ions (the... 

Figure 1. Schematic diagram of the discharge tube and mass spectrometer— (1) platinum wire anode (2) cylindrical discharge tube (3) extraction electrode (4) mass spectrometer ionization chamber (5) focussing electrodes (6) electron multiplier (7) electron-gun assembly. Typical voltages used on these electrodes during ion extraction from the discharge tube, are with respect to ground as follows (2) + 50 volts (3) — 50 volts (4), and inner electrode, 0 volts (5), part close to (4), — 25 volts (5), part close to quadrupole, + 100 volts quadrupole...

Fig. 2. Schematic diagram of a crossed-beam scattering spectrometer15 A—vacuum chamber, B—ion source, C— primary mass selector, D—deceleration lens, E—molecular beam, F—chopper, G—collision zone, H—detection slit, I—energy analyser, J—analysing mass spectrometer, K.— electron multiplier.

Figure 15. Schematic diagram of the ZAB mass spectrometer where S is the electron attachment ion source, CC1, CC2, and CC3 are collision cells, Dl, D2, and D3 are ion detectors, B is an analyzing magnet, E is an electric field energy analyzer, q is the quadrupole field, Q is the quadrupole mass filter, and DO is ion optics.

Figure 3. (a) Schematic diagram of the Brookhaven transient FM spectrometer, in which EOM = electrooptic modulator and SA = spectrum analyzer, (b) Schematic diagram of the FM detection electronics, in which LO = local oscillator, L pass = low pass filter. [Reprinted with permission from S. W. North, X. S. Zheng, R. Fei, and G. E. Hall, J. Chem. Phys., 104(6), 2129-5. Copyright 1996 American Institute of Physics.]... 

Figure 17.3.5 Schematic diagram of X-ray photoelectron spectrometer with an electrostatic hemispherical analyzer. The detector is usually a channel electron multipher. [From J. J. Pireaux and R. Sporken in M. Grasserbauer and H. W. Werner, Eds., Analysis of Microelectronic Materials and Devices, Wiley, New York, 1991, with permission.]...

Figure 17.3.15 Top left a) Schematic diagram of apparatus for DEMS. The chamber connected directly to the electrochemical cell and the mass spectrometer (MS) are pumped differentially by turbo pumps PA and PB. Electrolysis products are passed into the ionization chamber (1), analyzed in the quadrupole mass filter (2), and detected with either a Faraday cup (3) or electron multiplier...

Figure 2.13 Schematic diagram of the inside of an FTIR spectrometer showing the position of the Michelson interferometer (Reproduced by kind permission of Thermo Electron Corp.).

A schematic diagram of a mass spectrometer is shown in Figure 12.1. The substance to be studied is introduced into a chamber where a beam of electrons converts the molecule into positive ions. For example, when a water molecule is struck by an electron of suitable energy, an electron is knocked out of it with the formation of an HiO ion ... 

Fig. 2. Schematic diagram of the high-resolution double-focusing mass spectrometer. The insert shows an enlarged view of the ion extraction optics for the high-extraction-efficiency mode. P, pusher electrode C, collision chamber B, electron beam (z direction) S, collision chamber exit slit S2, penetrating field extraction slit S3, grounded slit S4 and Ss, deflector electrodes.

Figure 15.6. Schematic diagram of an electron spectrometer. The electrostatic analyzer sorts or spreads out the photoelectrons. Auger electrons, and other secondary electrons of various energies so that only monoenergetic electrons reach the detector. In this, the energy analyzer serves much the same function as does a monochromator in optical spectroscopy.

Figure 16.16. Schematic diagram of a typical field-ionization source. This source is simply substituted for the conventional electron-impact source. The remainder of the mass spectrometer is the same. Combined El/FI sources have been used.

Figure 14.26 Schematic diagram of an Auger spectrometer, showing the electron gun source, an electron flood gun and an ion gun, along with a carousel for multiple samples. The vacuum system is not shown. [Courtesy of Physical Electronics USA, Inc. Eden Prairie, MN (www.phi.com).]...

Schematic diagram of Auger electron appearance potential spectrometer. Thermionic electrons passing through an aperture in the anode impinge on the sample. Signal is extracted by the potential modulation technique.

Figure 1 Photograph and schematic diagram of a modern reverse geometry mass spectrometer coupled to a GC. (Reproduced with permission from Thermo Electron (Bremen).)...

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