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Physics Faculty Research & Creative Works

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Articles 571 - 600 of 1762

Full-Text Articles in Physical Sciences and Mathematics

Localizability Of Tachyonic Particles And Neutrinoless Double Beta Decay, Ulrich D. Jentschura, Benedikt J. Wundt Feb 2012

Localizability Of Tachyonic Particles And Neutrinoless Double Beta Decay, Ulrich D. Jentschura, Benedikt J. Wundt

Physics Faculty Research & Creative Works

The quantum field theory of superluminal (tachyonic) particles is plagued by a number of problems, which include the Lorentz non-invariance of the vacuum state, the ambiguous separation of the field operator into creation and annihilation operators under Lorentz transformations, and the necessity of a complex reinterpretation principle for quantum processes. Another unsolved question concerns the treatment of subluminal components of a tachyonic wave packet in the field-theoretical formalism, and the calculation of the time-ordered propagator. After a brief discussion on related problems, we conclude that rather painful choices have to be made in order to incorporate tachyonic spin-1/2 particles into …

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Artificially Disordered Birefringent Optical Fibers, Sumudu Herath, N. P. Puente, Elena I. Chaikina, Alexey Yamilov Feb 2012

Artificially Disordered Birefringent Optical Fibers, Sumudu Herath, N. P. Puente, Elena I. Chaikina, Alexey Yamilov

Physics Faculty Research & Creative Works

We develop and experimentally verify a theory of evolution of polarization in artificially-disordered multi-mode optical fibers. Starting with a microscopic model of photo-induced index change, we obtain the first and second order statistics of the dielectric tensor in a Ge-doped fiber, where a volume disorder is intentionally inscribed via UV radiation transmitted through a diffuser. A hybrid coupled-power & coupled-mode theory is developed to describe the transient process of de-polarization of light launched into such a fiber. After certain characteristic distance, the power is predicted to be equally distributed over all co-propagating modes of the fiber regardless of their polarization. …

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Enhancement Of Blackbody Friction Due To The Finite Lifetime Of Atomic Levels, G. Łach, M. Dekieviet, Ulrich D. Jentschura Jan 2012

Enhancement Of Blackbody Friction Due To The Finite Lifetime Of Atomic Levels, G. Łach, M. Dekieviet, Ulrich D. Jentschura

Physics Faculty Research & Creative Works

The thermal friction force acting on an atom moving relative to a thermal photon bath is known to be proportional to an integral over the imaginary part of the frequency-dependent atomic (dipole) polarizability. using a numerical approach, we find that blackbody friction on atoms either in dilute environments or in hot ovens is larger than previously thought by orders of magnitude. This enhancement is due to far off-resonant driving of transitions by low-frequency thermal radiation. at typical temperatures, the blackbody radiation maximum lies far below the atomic transition wavelengths. Surprisingly, due to the finite lifetime of atomic levels, which gives …

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Multiscale Perturbative Approach To Su(2)-Higgs Classical Dynamics: Stability Of Nonlinear Plane Waves And Bounds Of The Higgs Field Mass, V. Achilleos, F. K. Diakonos, D. J. Frantzeskakis, Garyfallia C. Katsimiga, X. N. Maintas, C. E. Tsagkarakis, A. Tsapalis Jan 2012

Multiscale Perturbative Approach To Su(2)-Higgs Classical Dynamics: Stability Of Nonlinear Plane Waves And Bounds Of The Higgs Field Mass, V. Achilleos, F. K. Diakonos, D. J. Frantzeskakis, Garyfallia C. Katsimiga, X. N. Maintas, C. E. Tsagkarakis, A. Tsapalis

Physics Faculty Research & Creative Works

We study the classical dynamics of SU(2)-Higgs field theory using multiple-scale perturbation theory. In the spontaneously broken phase, assuming small perturbations of the Higgs field around its vacuum expectation value, we derive a nonlinear Schrödinger equation and study the stability of its nonlinear plane wave solutions. The latter turn out to be stable only if the Higgs amplitude is an order of magnitude smaller than that of the gauge field. In this case, the Higgs field mass possesses some bounds which may be relevant to the search for the Higgs particle at ongoing experiments. © 2012 American Physical Society.

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Multiple Ionization Of Ne In Coincidence With Partially Stripped B ²⁺ Ions In The Intermediate Energy Regime, W. Wolff, H. Luna, A. C.F. Santos, E. C. Montenegro, Robert D. Dubois, C. C. Montanari, J. E. Miraglia Jan 2012

Multiple Ionization Of Ne In Coincidence With Partially Stripped B ²⁺ Ions In The Intermediate Energy Regime, W. Wolff, H. Luna, A. C.F. Santos, E. C. Montenegro, Robert D. Dubois, C. C. Montanari, J. E. Miraglia

Physics Faculty Research & Creative Works

A projectile ion-recoil ion and electron-recoil ion coincidence technique has been used to study the multiple ionization process in collisions of 0.75-4.0MeV B2+ with Ne atoms. Absolute total and partial pure ionization cross sections are reported for the first time at these impact energies with the present setup. the relative contribution of each recoil charge state has been investigated. the experimental data are compared to CDW-EIS calculation and with He2+ projectiles. the data throw further light on the effect of projectile screening in the ionization of multi-electronic targets and provide a support for the validity of the CDW-EIS …

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Effect Of Projectile Coherence On Atomic Fragmentation Processes, Michael Schulz, Kisra N. Egodapitiya, Sachin D. Sharma, Aaron C. Laforge, Robert Moshammer, A. A. Hasan, Don H. Madison Jan 2012

Effect Of Projectile Coherence On Atomic Fragmentation Processes, Michael Schulz, Kisra N. Egodapitiya, Sachin D. Sharma, Aaron C. Laforge, Robert Moshammer, A. A. Hasan, Don H. Madison

Physics Faculty Research & Creative Works

We demonstrate that the projectile coherence can have a major impact on atomic fragmentation processes. This has been overlooked for decades in formal scattering theory and may explain puzzling discrepancies between theoretical and experimental fully differential cross sections for single ionization.

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Strongly Enhanced Backward Emission Of Electrons In Transfer And Ionization, Michael Schulz, Xincheng Wang, M. Gundmundsson, Katharina R. Schneider, Aditya H. Kelkar, Alexander B. Voitkiv, B. Najjari, Markus S. Schoffler, Lothar Ph H H Schmidt, Reinhard Dorner, Joachim Hermann Ullrich, Robert Moshammer, Daniel Fischer Jan 2012

Strongly Enhanced Backward Emission Of Electrons In Transfer And Ionization, Michael Schulz, Xincheng Wang, M. Gundmundsson, Katharina R. Schneider, Aditya H. Kelkar, Alexander B. Voitkiv, B. Najjari, Markus S. Schoffler, Lothar Ph H H Schmidt, Reinhard Dorner, Joachim Hermann Ullrich, Robert Moshammer, Daniel Fischer

Physics Faculty Research & Creative Works

We studied three-dimensional angular distributions and longitudinal momentum spectra of electrons ejected in transfer plus ionization (TI), i.e., the ejection of one and the capture of a second target electron, for ion-helium collisions. We observe a pronounced structure strongly focused opposite to the projectile beam direction, which we associate with a new correlated TI mechanism proposed recently. This process contributes significantly to the total cross sections over a broad range of perturbations η, even at η as large as 0.5, where uncorrelated TI mechanisms were thought to be dominant.

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Electron- And Proton-Impact Excitation In Stored Hydrogenlike Uranium Ions, A. Gumberidze, D. B. Thorn, S. Trotsenko, D. Banaś, H. Beyer, W. Chen, R. D. Dubois, S. Geyer, R. Grisenti, S. Hagmann, M. Hegewald, S. Hess, P. Indelicato, C. Kozhuharov Jan 2012

Electron- And Proton-Impact Excitation In Stored Hydrogenlike Uranium Ions, A. Gumberidze, D. B. Thorn, S. Trotsenko, D. Banaś, H. Beyer, W. Chen, R. D. Dubois, S. Geyer, R. Grisenti, S. Hagmann, M. Hegewald, S. Hess, P. Indelicato, C. Kozhuharov

Physics Faculty Research & Creative Works

The projectile excitation of high-Z ions has been investigated in relativistic ion-atoms collisions by observing the subsequent x-ray emission. within this experiment information about the population of the magnetic sublevels has been obtained via an angular differential study of the decay photons associated with the subsequent de-excitation process. in addition, we have observed for the first time the effect of electron-impact excitation in a heavy highly charged ion undergoing a collision with a neutral atom.

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Differential Cross Sections For Single Ionization Of H₂ By 75kev Proton Impact, Uttam Chowdhury, Michael Schulz, Don H. Madison Jan 2012

Differential Cross Sections For Single Ionization Of H₂ By 75kev Proton Impact, Uttam Chowdhury, Michael Schulz, Don H. Madison

Physics Faculty Research & Creative Works

We have calculated Triply differential cross sections (TDCS) and doubly differential cross sections (DDCS) for single ionization of H2 by 75 keV proton impact using the molecular 3 body distorted wave Eikonal initial state (M3DW-EIS) approach. Previously published measured DDCS-P (differential in the projectile scattering angle and integrated over the ejected electron angles) found pronounced structures at relatively large angles which were interpreted as an interference resulting from the two-centered potential of the molecule.

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Kinematically Complete Studies On Mutual Projectile And Target Ionization, X. Wang, D. Fischer, A. Kelkar, K. Schneider, Michael Schulz, B. Najjari, A. Voitkiv, M. Gudmundsson, M. Grieser, R. Moshammer, J. Ullrich Jan 2012

Kinematically Complete Studies On Mutual Projectile And Target Ionization, X. Wang, D. Fischer, A. Kelkar, K. Schneider, Michael Schulz, B. Najjari, A. Voitkiv, M. Gudmundsson, M. Grieser, R. Moshammer, J. Ullrich

Physics Faculty Research & Creative Works

Mutual projectile and target ionizations (MPTI) of 1MeV/amu N4+ and N5+ +He collisions have been studied in kinematically complete experiments; the data is presented in four-particle (4-D) Dalitz plots. comparison to eikonal approximation (EA) calculation results shows qualitatively good agreement.

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Comparison Of Experiment And Theory For Electron Impact Ionization Of Isoelectronic Atoms And Molecules, Hari Chaluvadi, Kate L. Nixon, Sadek M. Amami, Andrew James Murray, Don H. Madison Jan 2012

Comparison Of Experiment And Theory For Electron Impact Ionization Of Isoelectronic Atoms And Molecules, Hari Chaluvadi, Kate L. Nixon, Sadek M. Amami, Andrew James Murray, Don H. Madison

Physics Faculty Research & Creative Works

Experimental and Theoretical Triply Differential Cross sections will be presented for low energy electron impact ionization of Ne, CH4, and NH3. The collision mechanisms responsible for the various structures found in the cross sections will be discussed.

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Intensity Dependence Of Multiple Orbital Contributions And Shape Resonance In High-Order Harmonic Generation Of Aligned N₂ Molecules, Cheng Jin, Julien B. Bertrand, R. R. Lucchese, H .J. Worner, Paul B. Corkum, D. M. Villeneuve, Anh-Thu Le, C. D. Lin Jan 2012

Intensity Dependence Of Multiple Orbital Contributions And Shape Resonance In High-Order Harmonic Generation Of Aligned N₂ Molecules, Cheng Jin, Julien B. Bertrand, R. R. Lucchese, H .J. Worner, Paul B. Corkum, D. M. Villeneuve, Anh-Thu Le, C. D. Lin

Physics Faculty Research & Creative Works

We report measurements and theoretical simulations of high-order harmonic generation (HHG) in aligned N₂ molecules using a 1200-nm intense laser field when the generating pulse is perpendicular to the aligning one. With increasing laser intensity, the minimum in the HHG spectra first shifts its position and then disappears. Theoretical simulations including the macroscopic propagation effects in the medium reproduce these observations and the disappearance of the minimum is attributed to the additional contribution of HHG from inner orbitals. We also predict that the well-known shape resonance in the photoionization spectra of N₂ should exist in the HHG spectra. It is …

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Experimental And Theoretical Investigation Of The Triple Differential Cross Section For Electron Impact Ionization Of Pyrimidine Molecules, J. D. Builth-Williams, Susan M. Bellm, Darryl B. Jones, Hari Chaluvadi, Don H. Madison, Chuangang Ning, B. Lohmann, Michael J. Brunger Jan 2012

Experimental And Theoretical Investigation Of The Triple Differential Cross Section For Electron Impact Ionization Of Pyrimidine Molecules, J. D. Builth-Williams, Susan M. Bellm, Darryl B. Jones, Hari Chaluvadi, Don H. Madison, Chuangang Ning, B. Lohmann, Michael J. Brunger

Physics Faculty Research & Creative Works

Cross-section data for electron impact induced ionization of bio-molecules are important for modelling the deposition of energy within a biological medium and for gaining knowledge of electron driven processes at the molecular level. Triply differential cross sections have been measured for the electron impact ionization of the outer valence 7b 2 and 10a 1 orbitals of pyrimidine, using the (e, 2e) technique. The measurements have been performed with coplanar asymmetric kinematics, at an incident electron energy of 250 eV and ejected electron energy of 20 eV, for scattered electron angles of -5°, -10°, and -15°. The ejected electron angular range …

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All-Sky Search For Periodic Gravitational Waves In The Full S5 Ligo Data, J. Abadie, Marco Cavaglia, For Full List Of Authors, See Publisher's Website. Jan 2012

All-Sky Search For Periodic Gravitational Waves In The Full S5 Ligo Data, J. Abadie, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

We report on an all-sky search for periodic gravitational waves in the frequency band 50-800Hz and with the frequency time derivative in the range of 0 through -6 x 10-9Hz/s. Such a signal could be produced by a nearby spinning and slightly nonaxisymmetric isolated neutron star in our Galaxy. After recent improvements in the search program that yielded a 10x increase in computational efficiency, we have searched in two years of data collected during LIGO's fifth science run and have obtained the most sensitive all-sky upper limits on gravitational-wave strain to date. Near 150Hz our upper limit on …

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An Investigation Of Guiding Of Positrons Through Insulating Capillaries, Robert D. Dubois, K. Tökési Jan 2012

An Investigation Of Guiding Of Positrons Through Insulating Capillaries, Robert D. Dubois, K. Tökési

Physics Faculty Research & Creative Works

Guiding of diffuse low-intensity positron and electron beams through macroscopic tapered insulating capillaries was investigated. Transmitted positrons and electrons were observed. However, further investigations are necessary to clarify whether the transmitted particles are a true indication of guiding or simply due to a range of diffuse angles of the incoming beams.

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Triply Differential Measurements For Single Ionization Of Molecular Nitrogen By 250 Ev Positron Impact, Robert D. Dubois, O. G. De Lucio Jan 2012

Triply Differential Measurements For Single Ionization Of Molecular Nitrogen By 250 Ev Positron Impact, Robert D. Dubois, O. G. De Lucio

Physics Faculty Research & Creative Works

Triply differential cross sections are presented for 250 eV positron impact single ionization of molecular nitrogen. Data are presented for binary and recoil interactions resulting from projectiles being scattered between 0 and 5 degrees and energy losses up to approximately 50 eV.

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X-Ray Emission Cross Sections Following Charge Exchange Collisions On Neutral Targets: The Role Of Multiple Electron Capture, Sebastian Otranto, Ronald E. Olson Jan 2012

X-Ray Emission Cross Sections Following Charge Exchange Collisions On Neutral Targets: The Role Of Multiple Electron Capture, Sebastian Otranto, Ronald E. Olson

Physics Faculty Research & Creative Works

Line emission and charge exchange cross sections obtained from a three-active electrons CTMC code allow us to determine the role of multiple electron capture for charge exchange collisions on neutral argon and neon. the present results can be compared to recent experimental data from EBIT groups operating at Liver-more, NIST and Berlin.

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Reaction Dynamics In Double Ionization Of Helium By Electron Impact, Michael Schulz, M. F. Ciappina, T. Kirchner Jan 2012

Reaction Dynamics In Double Ionization Of Helium By Electron Impact, Michael Schulz, M. F. Ciappina, T. Kirchner

Physics Faculty Research & Creative Works

Multiple differential cross sections for double ionization of helium by electron impact were calculated within various models. using a Monte Carlo Event Generator technique, additional physics, not included in the primary calculations, are modeled and cross sections are convoluted with the experimental resolution.

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Electron Loss By Fast Heavy Ions: Target Scaling Dependence, Robert D. Dubois, A. C.F. Santos, G. M. Sigaud, E. C. Montenegro Jan 2012

Electron Loss By Fast Heavy Ions: Target Scaling Dependence, Robert D. Dubois, A. C.F. Santos, G. M. Sigaud, E. C. Montenegro

Physics Faculty Research & Creative Works

Using data taken from the literature, the scaling of electron loss cross sections as a function of target Z was investigated. It was found that for energies /u, a wide range of systems demonstrated very similar target Z dependences where, for heavier targets, the slope increased very slowly with impact energy. at higher energies, this increase was much faster. a "universal" formula capable of fitting these dependences is being developed.

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Scattering Angle Dependence Of Double Differential Cross Sections For Dissociative Ionization Of H2 By Proton Impact, Michael Schulz, K. Egodapitiya, S. Sharma, A. C. Laforge Jan 2012

Scattering Angle Dependence Of Double Differential Cross Sections For Dissociative Ionization Of H2 By Proton Impact, Michael Schulz, K. Egodapitiya, S. Sharma, A. C. Laforge

Physics Faculty Research & Creative Works

We have measured double differential cross sections for dissociative ionization of H2 by 75 keV proton impact for fixed energy losses as a function scattering angle. the data exhibit an oscillating pattern with a frequency about twice as large as found earlier for non-dissociative ionization. © Published under licence by IOP Publishing Ltd.

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Electron Transfer And Ionization In Collisions Of He-Like Ions With Na(3s) And Na(3p), I. Blank, S. Otrantcr, C. Meinema, Ronald E. Olson, R. Hoekstra Jan 2012

Electron Transfer And Ionization In Collisions Of He-Like Ions With Na(3s) And Na(3p), I. Blank, S. Otrantcr, C. Meinema, Ronald E. Olson, R. Hoekstra

Physics Faculty Research & Creative Works

Single electron transfer and ionization in collisions of He-like ions (N5+, O6+, Ne8+) and Na has been investigated both experimentally and theoretically at energies around the matching velocity of the valence electron (2 to 10 keV/amu). State selective cross sections and scattering angle distributions were obtained using recoil-ion momentum spectroscopy in combination with a magneto-optically cooled Na atom target. a strong dependence of the relative cross sections on the collision energy is observed. the results are compared with Classical-Trajectory Monte Carlo (CTMC) calculations and show an overall very good agreement.

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Systematic Analysis Of Four-Particle Dalitz Plots For Double Ionization, Michael Schulz, D. Fischer, K. Schneider, R. Moshammer, J. Ullrich, M. F. Ciappina, T. Kirchner Jan 2012

Systematic Analysis Of Four-Particle Dalitz Plots For Double Ionization, Michael Schulz, D. Fischer, K. Schneider, R. Moshammer, J. Ullrich, M. F. Ciappina, T. Kirchner

Physics Faculty Research & Creative Works

Four particle Dalitz plots for double ionization of helium by ion impact were analyzed.

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Thermal Correction To The Molar Polarizability Of A Boltzmann Gas, Ulrich D. Jentschura, Mariusz Puchalski, Peter J. Mohr Dec 2011

Thermal Correction To The Molar Polarizability Of A Boltzmann Gas, Ulrich D. Jentschura, Mariusz Puchalski, Peter J. Mohr

Physics Faculty Research & Creative Works

Metrology in atomic physics has been crucial for a number of advanced determinations of fundamental constants. In addition to very precise frequency measurements, the molar polarizability of an atomic gas has recently also been measured very accurately. Part of the motivation for the measurements is due to ongoing efforts to redefine the International System of Units (SI), for which an accurate value of the Boltzmann constant is needed. Here we calculate the dominant shift of the molar polarizability in an atomic gas due to thermal effects. It is given by the relativistic correction to the dipole interaction, which emerges when …

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Prospects For Determination Of Thermal History After Inflation With Future Gravitational Wave Detectors, Sachiko Kuroyanagi, Kazunori Nakayama, Shun Saito Dec 2011

Prospects For Determination Of Thermal History After Inflation With Future Gravitational Wave Detectors, Sachiko Kuroyanagi, Kazunori Nakayama, Shun Saito

Physics Faculty Research & Creative Works

Thermal history of the Universe between inflation and big-bang nucleosynthesis has not yet been revealed observationally. It will be probed by the detection of primordial gravitational waves generated during inflation, which contain information on the reheating temperature as well as the equation of state of the Universe after inflation. Based on the Fisher information formalism, we examine how accurately the tensor-to-scalar ratio and reheating temperature after inflation can be simultaneously determined with space-based gravitational wave detectors such as the DECI-hertz Interferometer Gravitational-wave Observatory and the Big-Bang Observer. We show that the reheating temperature is best determined if it is around …

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Directional Limits On Persistent Gravitational Waves Using Ligo S5 Science Data, J. Abadie, Marco Cavaglia, For Full List Of Authors, See Publisher's Website. Dec 2011

Directional Limits On Persistent Gravitational Waves Using Ligo S5 Science Data, J. Abadie, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

The gravitational-wave (GW) sky may include nearby pointlike sources as well as stochastic backgrounds. We perform two directional searches for persistent GWs using data from the LIGO S5 science run: one optimized for pointlike sources and one for arbitrary extended sources. Finding no evidence to support the detection of GWs, we present 90% confidence level (C.L.) upper-limit maps of GW strain power with typical values between 2 - 20 x 10-50 strain2 Hz-1 and 5 - 35 x 10-49 strain2Hz-1sr-1 for pointlike and extended sources, respectively. The latter result is the …

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Quantum Phase Transition Of The Sub-Ohmic Rotor Model, Manal Al-Ali, Thomas Vojta Nov 2011

Quantum Phase Transition Of The Sub-Ohmic Rotor Model, Manal Al-Ali, Thomas Vojta

Physics Faculty Research & Creative Works

We investigate the behavior of an N-component quantum rotor coupled to a bosonic dissipative bath having a sub-Ohmic spectral density J (ω) ∝ ωs with s < 1.With increasing dissipation strength, this system undergoes a quantum phase transition from a delocalized phase to a localized phase.We determine the exact critical behavior of this transition in the large-N limit. For 1 > s > 1/2, we find nontrivial critical behavior corresponding to an interacting renormalization group fixed point, while we find mean-field behavior for s < 1/2. The results agree with those of the corresponding long-range …

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Influence Of Gas Pressure On High-Order-Harmonic Generation Of Ar And Ne, Guoli Wang, Cheng Jin, Anh-Thu Le, C. D. Lin Nov 2011

Influence Of Gas Pressure On High-Order-Harmonic Generation Of Ar And Ne, Guoli Wang, Cheng Jin, Anh-Thu Le, C. D. Lin

Physics Faculty Research & Creative Works

We study the effect of gas pressure on the generation of high-order harmonics where harmonics due to individual atoms are calculated using the recently developed quantitative rescattering theory, and the propagation of the laser and harmonics in the medium is calculated by solving the Maxwell's wave equation. We illustrate that the simulated spectra are very sensitive to the laser focusing conditions at high laser intensity and high pressure since the fundamental laser field is severely reshaped during the propagation. By comparing the simulated results with several experiments we show that the pressure dependence can be qualitatively explained. The lack of …

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Infinite-Randomness Criticality In A Randomly Layered Heisenberg Magnet, Fawaz Hrahsheh, Hatem Barghathi, Thomas Vojta Nov 2011

Infinite-Randomness Criticality In A Randomly Layered Heisenberg Magnet, Fawaz Hrahsheh, Hatem Barghathi, Thomas Vojta

Physics Faculty Research & Creative Works

We study the ferromagnetic phase transition in a randomly layered Heisenberg magnet using large-scale Monte Carlo simulations. Our results provide numerical evidence for the infinite-randomness scenario recently predicted within a strong-disorder renormalization-group approach. Specifically, we investigate the finite-size scaling behavior of the magnetic susceptibility, which is characterized by a nonuniversal power-law divergence in the Griffiths phase. We also study the perpendicular and parallel spin-wave stiffnesses in the Griffiths phase. In agreement with the theoretical predictions, the parallel stiffness is nonzero for all temperatures T < Tc. In contrast, the perpendicular stiffness remains zero in part of the ordered phase, giving …

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Effectiveness Of Projectile Screening In Single And Multiple Ionization Of Ne By B2⁺, W. Wolff, H. Luna, A. C.F. Santos, E. C. Montenegro, Robert D. Dubois, C. C. Montanari, J. E. Miraglia Oct 2011

Effectiveness Of Projectile Screening In Single And Multiple Ionization Of Ne By B2⁺, W. Wolff, H. Luna, A. C.F. Santos, E. C. Montenegro, Robert D. Dubois, C. C. Montanari, J. E. Miraglia

Physics Faculty Research & Creative Works

Pure multiple ionization cross sections of Ne by B2+ projectiles have been measured in the energy range of 0.75 to 4.0 MeV and calculated using the continuum distorted wave-eikonal initial state approximation. the experiment and calculations show that the ionization cross sections by B2+, principally for the production of highly charged recoils, is strongly enhanced when compared to the bare projectile with the same charge state, He2+, at the same velocities. © 2011 American Physical Society.

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Reply To "Comment On 'Counterintuitive Consequence Of Heating In Strongly-Driven Intrinsic Junctions Of Bi₂Sr₂Cacu₂O 8+Δ Mesas'", Cihan Kurter, Lutfi Ozyuzer, Thomas Proslier, John F. Zasadzinski, David G. Hinks, Kenneth E. Gray Oct 2011

Reply To "Comment On 'Counterintuitive Consequence Of Heating In Strongly-Driven Intrinsic Junctions Of Bi₂Sr₂Cacu₂O 8+Δ Mesas'", Cihan Kurter, Lutfi Ozyuzer, Thomas Proslier, John F. Zasadzinski, David G. Hinks, Kenneth E. Gray

Physics Faculty Research & Creative Works

The main criticism raised in the preceding Comment concerns our suggestion that sharp conduction peaks in Bi2Sr2CaCu2O 8+δ mesas, along with absent dip-hump features, may, in general, be a result of self-heating. The author points to the variety of experimental configurations, matrix-element effects, and doping dependencies that might allow a diversity of conductance spectra. We argue that numerous mesa studies (with fixed matrix elements) firmly establish the systematic development of sharp conductance peaks with increased self-heating, and thus, the issue of nonuniversality of tunneling characteristics is not relevant. The author mentions a number of studies that …

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