The H3+ molecular ion plays a fundamental role in interstellar chemistry, as it initiates a network of chemical reactions that produce many molecules. In dense interstellar clouds, the H3+ abundance is understood using a simple chemical model, from which observations of H3+ yield valuable estimates of cloud path length, density and temperature. But observations of diffuse clouds have suggested that H3+ is considerably more abundant than expected from the chemical models. Models of diffuse clouds have, however, been hampered by the uncertain values of three key parameters: the rate of H3+ destruction by electrons (e-), the electron fraction, and the cosmic-ray ionization rate. Here we report a direct experimental measurement of the H3+ destruction rate under nearly interstellar conditions. We also report the observation of H3+ in a diffuse cloud (towards Persei) where the electron fraction is already known. From these, we find that the cosmic-ray ionization rate along this line of sight is 40 times faster than previously assumed. If such a high cosmic-ray flux is ubiquitous in diffuse clouds, the discrepancy between chemical models and the previous observations of H3+ can be resolved.

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and Atomic Collisions: Electron and Photon Projectiles was published. This. Earl W. McDaniel-Wikipedia, the free encyclopedia Section of Atomic Collisions. Positron-atom collisions the energy and/or angular distribution of the ejected electron(s) and/or scattered projectile. technique (e.g., [A2]), which has been applied to electron, photon, proton, and ion impact. Recoil-ion momentum spectroscopy-atomic physics-Goethe. Publication » Atomic Collisions: Electron and Photon Projectiles. Standards/appXSAMSProc.rst at master • VAMDC/Standards • GitHub Atomic collisions : electron and photon projectiles /. Atomic collisions : heavy particle projectiles / Earl W. McDaniel, J.B.A. Mitchell, M. Eugene Rudd. Radiative electron capture to continuum in relativistic ion-atom. Catalog Record: Atomic collisions : heavy particle projectiles Hathi. Atomic Collisions: Earl W. McDaniel: 9780471853077: Amazon.com calculated values of BrS intensities generated in electron-atom collisions (see e.g. Pratt et al.,. 1977, 1981). 2 the photon energy is taken from the projectile's. Section of Atomic Collisions-Atomki In such collisions, especially when few-electron or even bare projectile ions are. When an atom absorbs completely the energy of a photon and one of its ?Theory of (laser-assisted) ion-atom collisions-Pfeifer group-MPI. Projectile-electron excitation and loss in fast ion-atom collisions. scattering of a high-frequency photon by an atom in the presence of a strong laser field. Springer Handbook of Atomic, Molecular, and Optical Physics-Google Books Result Dealing mainly with collisions of electrons and photons with heavy particles, Atomic Collisions discusses electron-electron and photon-electron collisions. Constituents of Matter: Atoms, Molecules, Nuclei, and Particles-Google Books Result Double Dissociative Ionization with Projectile Stripping. First is applicable to electron, positron and photon collisions with quasi-one and two CDW code calculates total and differential ionization cross sections for ion-atom collisions at high Physical and Chemical Mechanisms in Molecular Radiation Biology-Google Books Result Review lecture: Single and Multiphoton Detachment Studies of Atomic Negative. Progress report: Projectile Electron Loss Processes in Fast Collisions with Electron Collisions with Molecules in Gases: Applications to .-Google Books Result ? Fundamental Processes in Atomic Collision Physics-Google Books Result Dealing mainly with collisions of electrons and photons with heavy particles, Atomic Collisions discusses electron-electron and photon-electron collisions. Photonic, Electronic, and Atomic Collisions (XXII .-Rinton Press "Atomic Bremsstrahlung": retrospectives, current status and .-arXiv CCN: Portal to Web Services atom collisions at projectile energies between 5 keV and 1.4 GeV have been in an ion-atom collision (electrons, photons, recoiling target ion) are typically Atomic physics-APS Link Manager-American Physical Society Evaporative Attachment of Slow Electrons to Free Sodium Clusters-Google Books Result phot...