Vacuum energy photons

In this section, we present an overview of the photoabsorption cross section (o ) and the photoionization quantum yields (rh) for normal alkanes, C H2 +2 ( = 1 ), as a function of the incident photon energy in the vacuum ultraviolet range, and of the number of carbon atoms in the alkane molecule, because normal alkanes are typical polyatomic molecules of chemical interest. In Fig. 5, the vertical ionization potentials of the valence electrons, which interact with the vacuum ultraviolet photons, in each of these alkane molecules are indicated to show how the outer- and inner-valence orbitals associated with carbon 2p and 2s orbitals, respectively, locate in energy [7]. 

Recently, a group in the United Kingdom started to study the effect of vacuum UV photons using the Daresbury synchrotron facility. They measured the yields of ssb and dsb in plasmid DNA, and proposed that the mechanism or a precursor to produce both types of strand breaks are common, because the photon energy dependence is similar for both types, although the absolute yield differed by 50-fold [17]. They confirmed that double... 

Prise, K.M. Folkard, M. Michael, B.D. Vojnovic, B. Brocklehurst, B. Hopkirk, A. Munro, I.H. Critical energies for SSB and DSB induction in plasmid DNA by low-energy photons action spectra for strand-break induction in plasmid DNA irradiated in vacuum. Int. J. Radiat. Biol. 200, 76 (7), 881-890. 

Watanabe, R. Usami, N. Takakura, K. Hieda, K. Kobayashi, K. Water radical 5uelds by low energy vacuum ultraviolet photons as measured with Fricke dosimeter. Radiat. Res. 1997,148, 489-490. 

Time-like currents and flows do appear in the vacuum energy, if extended electrodynamic theory is utilized. For instance, in the received view, the Gupta-Bleuler method removes time-like photons and longitudinal photons. For disproof of the Gupta-Bleuler method, proof of the independent existence of such photons, and a short description of their characteristics, see Evans AIAS group papers on Whittaker s F and G fluxes and analysis of the EM entity in Ref. 24a to see how such entities produce ordinary EM fields and energy in vacuo, see Ref. 24b. 

Folkard M, Prise KM, Vojnovic B, Brocklehurst B, Michael BD (2000) Critical energies for ssb and dsb induction in plasmid DNA by vacuum-UV photons an arrangement for irrdiating dry or hydrated DNA with monochromatic photons. Int J Radiat Biol 76 763-771 Folkard M, Prise KM, Turner CJ, Michael BD (2002) The production of single strand and double strand breaks in aqueous solution by vacuum UV photons below 10 eV. Radiat Prot Dosim 99 147-149 FoxRA, Fielden EM, SaporaO (1976) Yield of single-strand breaks in the DNA of E. coli 10 msec after irradiation. Int J Radiat Biol 29 391-394... 

Gas Phase 03 Photolysis. From Table IV, it is apparent that it is energetically possible to produce any of the excited states42 of 0 and 02 depending on the energy of the vacuum ultraviolet photon. Thus, the reaction... 

The base state T ) ltB) stands for the beam s internal quantum state and the laser at frequency co. The base state l ) ()< ) represents the electronic excited state with no free electromagnetic energy quantum yet coupled to this "colored" vacuum. The high-energy photon is trapped in the atom as it were, and it will go through the cavity device as long as the entangled state does not spontaneously emit a photon hco. Such process would destroy the experiment, as we will see below. 

Down-conversion is another useful technique that has applications in lighting and plasma flat panel displays. The process involves the input of a vacuum ultraviolet photon and the output of multiple visible photons. This down-conversion was recently reported with Eu + doped LiGdp4. Upon absorption of a high-energy photon by Gd +, two visible photons were emitted through an energy transfer between Eu + and Gd + with a quantum... 

Photoemission spectroscopy involves measurement of the energy distribution of electrons emitted from a solid under irradiation with mono-energetic photons. In-house experiments are usually performed with He gas discharge lamps which generate vacuum UV photons at 21.2 eV (He la radiation) or 40.8 eV (He Ila radiation ) or with Mg Ka (hv=1284.6 eV) or A1 Ka (hv=1486.6eV) soft X-ray sources. UV photoemission is restricted to the study of valence and conduction band states, but XPS allows in addition the study of core levels. Alternatively photoemission experiments may be performed at national synchrotron radiation facilities. With suitable choice of monochromators it is possible to cover the complete photon energy range from about 5 eV upward to in excess of 1000 eV. The surface sensitivity of photoemission derives from the relatively short inelastic mean free path of electrons in solids, which reaches a minimum of about 5A for electron energies of the order 50-100 eV. 

A wide variety of desorption ionization methods is available [7] desorption chemical ionization (DCI), secondary-ion mass spectrometry (SIMS), fast-atom bombardment (FAB), liquid-SIMS, plasma desorption (PD), matrix-assisted laser desorption ionization (MALDI), and field desorption (FD). Two processes are important in the ionization mechanism, i.e., the formation of ions in the sample matrix prior to desorption, and rapid evaporation prior to ionization, which can be affected by very rapid heating or by sputtering by high-energy photons or particles. In addition, it is assumed that the energy deposited on the sample surface can cause (gas-phase) ionization reactions to occur near the interface of the solid or liquid and the vacuum (the so-called selvedge) or provide preformed ions in the condensed phase with sufficient kinetic energy to leave their environment. 

The radiative corrections depicted in Fig.l describe the interaction of the electron with the virtual photons (SE) and with vacuum electric current (VP). This interaction results in the shift of the atomic energy levels (Lamb Shift). It appears that not only the energy of the vacuum but also the energy of the interaction between atomic electron and the vacuum is infinite. Unlike the infinite vacuum energy the infinite interaction energy cannot be simply subtracted and a sophisticated procedure of renormalization is required to... 

By using much lower energy photons, Guichar et al. [45] have developed a high sensitivity technique which probes transitions between occupied surface and bulk states and states at or above the vacuum level. 

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