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Michael J. Brunger - One of the best experts on this subject based on the ideXlab platform.
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Differential Cross sections for electron impact vibrational excitation of tetrahydrofuran at intermediate impact energies
Journal of Chemical Physics, 2015Co-Authors: H V Duque, T P T Do, M C A Lopes, R D White, Michael J. Brunger, Dmitry A. Konovalov, D B JonesAbstract:We report Differential Cross sections (DCSs) for electron-impact vibrational-excitation of tetrahydrofuran, at intermediate incident electron energies (15-50 eV) and over the 10°-90° scattered electron angular range. These measurements extend the available DCS data for vibrational excitation for this species, which have previously been obtained at lower incident electron energies (≤20 eV). Where possible, our data are compared to the earlier measurements in the overlapping energy ranges. Here, quite good agreement was generally observed where the measurements overlapped.
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Differential Cross sections for the electron impact excitation of pyrimidine
Journal of Chemical Physics, 2012Co-Authors: D B Jones, Susan Bellm, Michel Fuss, P Limaovieira, F. Blanco, Gustavo Garcia, Michael J. BrungerAbstract:We report on Differential Cross section (DCS) measurements for the electron-impact excitation of the electronic states of pyrimidine. The energy range of the present measurements was 15–50 eV with the angular range of the measurements being 10°–90°. All measured DCSs displayed forward-peaked angular distributions, consistent with the relatively large magnitudes for the dipole moment and dipole polarizability of pyrimidine. Excitations to triplet states were found to be particularly important in some energy loss features at the lower incident electron energies. To the best of our knowledge there are no other experimental data or theoretical computations against which we can compare the present results.
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experimental and theoretical investigation of the triple Differential Cross section for electron impact ionization of pyrimidine molecules
Journal of Chemical Physics, 2012Co-Authors: J D Builthwilliams, Susan Bellm, D B Jones, Don H Madison, Hari Chaluvadi, Chuangang Ning, B Lohmann, Michael J. BrungerAbstract: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 7b2 and 10a1 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 encompasses both the binary and recoil peaks in the triple Differential Cross section. Corresponding theoretical calculations have been performed using the molecular 3-body distorted wave model and are in reasonably good agreement with the present experiment.
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Differential Cross sections and Cross section ratios for the electron impact excitation of the neon 2p 5 3s configuration
Physical Review A, 2002Co-Authors: M A Khakoo, Michael J. Brunger, S Trajmar, I Kanik, James M Wrkich, Mary Lu Larsen, G Kleiban, P J O Teubner, Albert Crowe, Christopher J FontesAbstract:Electron-impact Differential Cross-section measurements for the excitation of the ${2p}^{5}3s$ configuration of Ne are reported. The Ne Cross sections are obtained using experimental Differential Cross sections for the electron-impact excitation of the $n=2$ levels of atomic hydrogen [Khakoo et al., Phys. Rev. A 61, 012701-1 (1999)], and existing experimental helium Differential Cross-section measurements, as calibration standards. These calibration measurements were made using the method of gas mixtures (Ne and H followed by Ne and He), in which the gas beam profiles of the mixed gases are found to be the same within our experimental errors. We also present results from calculations of these Differential Cross sections using the R-matrix and unitarized first-order many-body theory, the distorted-wave Born approximation, and relativistic distorted-wave methods. Comparison with available experimental Differential Cross sections and Differential Cross-section ratios is also presented.
Dong H Zhang - One of the best experts on this subject based on the ideXlab platform.
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state to state quantum reactive scattering for four atom chemical reactions Differential Cross section for the h h2o h2 oh abstraction reaction
Journal of Chemical Physics, 2006Co-Authors: Dong H ZhangAbstract:The time-dependent wave packet method was extended to calculate the state-to-state Differential Cross section for the title four-atom abstraction reaction with H2O in the ground rovibrational state. One spectator OH bond length was fixed in the study, but the remaining five degrees of freedom were treated exactly. It was found that (a) the Differential Cross section changes from being strongly backward peaked at low collision energy to sideward scattering at E=1.4eV, and (b) the rotational state-resolved Differential Cross section for H2 differs substantially from that for OH.
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state to state quantum reactive scattering for four atom chemical reactions Differential Cross section for the h h2o h2 oh abstraction reaction
Journal of Chemical Physics, 2006Co-Authors: Dong H ZhangAbstract:The time-dependent wave packet method was extended to calculate the state-to-state Differential Cross section for the title four-atom abstraction reaction with H2O in the ground rovibrational state. One spectator OH bond length was fixed in the study, but the remaining five degrees of freedom were treated exactly. It was found that (a) the Differential Cross section changes from being strongly backward peaked at low collision energy to sideward scattering at E=1.4eV, and (b) the rotational state-resolved Differential Cross section for H2 differs substantially from that for OH.The time-dependent wave packet method was extended to calculate the state-to-state Differential Cross section for the title four-atom abstraction reaction with H2O in the ground rovibrational state. One spectator OH bond length was fixed in the study, but the remaining five degrees of freedom were treated exactly. It was found that (a) the Differential Cross section changes from being strongly backward peaked at low collision energy to sideward scattering at E=1.4eV, and (b) the rotational state-resolved Differential Cross section for H2 differs substantially from that for OH.
D B Jones - One of the best experts on this subject based on the ideXlab platform.
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Differential Cross sections for electron impact vibrational excitation of tetrahydrofuran at intermediate impact energies
Journal of Chemical Physics, 2015Co-Authors: H V Duque, T P T Do, M C A Lopes, R D White, Michael J. Brunger, Dmitry A. Konovalov, D B JonesAbstract:We report Differential Cross sections (DCSs) for electron-impact vibrational-excitation of tetrahydrofuran, at intermediate incident electron energies (15-50 eV) and over the 10°-90° scattered electron angular range. These measurements extend the available DCS data for vibrational excitation for this species, which have previously been obtained at lower incident electron energies (≤20 eV). Where possible, our data are compared to the earlier measurements in the overlapping energy ranges. Here, quite good agreement was generally observed where the measurements overlapped.
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Differential Cross sections for the electron impact excitation of pyrimidine
Journal of Chemical Physics, 2012Co-Authors: D B Jones, Susan Bellm, Michel Fuss, P Limaovieira, F. Blanco, Gustavo Garcia, Michael J. BrungerAbstract:We report on Differential Cross section (DCS) measurements for the electron-impact excitation of the electronic states of pyrimidine. The energy range of the present measurements was 15–50 eV with the angular range of the measurements being 10°–90°. All measured DCSs displayed forward-peaked angular distributions, consistent with the relatively large magnitudes for the dipole moment and dipole polarizability of pyrimidine. Excitations to triplet states were found to be particularly important in some energy loss features at the lower incident electron energies. To the best of our knowledge there are no other experimental data or theoretical computations against which we can compare the present results.
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experimental and theoretical investigation of the triple Differential Cross section for electron impact ionization of pyrimidine molecules
Journal of Chemical Physics, 2012Co-Authors: J D Builthwilliams, Susan Bellm, D B Jones, Don H Madison, Hari Chaluvadi, Chuangang Ning, B Lohmann, Michael J. BrungerAbstract: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 7b2 and 10a1 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 encompasses both the binary and recoil peaks in the triple Differential Cross section. Corresponding theoretical calculations have been performed using the molecular 3-body distorted wave model and are in reasonably good agreement with the present experiment.
J Antos - One of the best experts on this subject based on the ideXlab platform.
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measurement of the Differential Cross section dσ d cos θt for top quark pair production in pp collisions at s 1 96 tev
Physical Review Letters, 2013Co-Authors: T Aaltonen, S Amerio, D Amidei, A Anastassov, A Annovi, J Antos, G Apollinari, J A Appel, T ArisawaAbstract:We report a measurement of the Differential Cross section, d{sigma}/d(cos { heta}t), for top-quark-pair production as a function of the top-quark production angle in proton-antiproton collisions at sqrt{s} = 1.96 TeV. This measurement is performed using data collected with the CDF II detector at the Tevatron, corresponding to an integrated luminosity of 9.4/fb. We employ the Legendre polynomials to characterize the shape of the Differential Cross section at the parton level. The observed Legendre coefficients are in good agreement with the prediction of the next-to-leading-order standard-model calculation, with the exception of an excess linear-term coefficient, a1 = 0.40 +- 0.12, compared to the standard-model prediction of a1 = 0.15^{+0.07}_{-0.03}.
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first measurement of the tt Differential Cross section dσ dmtt in pp collisions at s 1 96tev
Physical Review Letters, 2009Co-Authors: T Aaltonen, S Amerio, D Amidei, A Anastassov, A Annovi, J Adelman, T Akimoto, Alvarez B Gonzalez, J AntosAbstract:We present a measurement of the tt Differential Cross section with respect to the tt invariant mass, dσ/dMtt, in pp collisions at s=1.96TeV using an integrated luminosity of 2.7fb-1 collected by the CDF II experiment. The tt invariant mass spectrum is sensitive to a variety of exotic particles decaying into tt pairs. The result is consistent with the standard model expectation, as modeled by PYTHIA with CTEQ5L parton distribution functions. © 2009 The American Physical Society.
G. Aad - One of the best experts on this subject based on the ideXlab platform.
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Differential Cross-section measurements for the electroweak production of dijets in association with a
'Springer Science and Business Media LLC', 2021Co-Authors: G. Aad, B. Abbott, D. C. Abbott, Abed A. Abud, K. Abeling, D. K. Abhayasinghe, S. H. Abidi, O. S. Abouzeid, N. L. Abraham, H. AbramowiczAbstract:Differential Cross-section measurements are presented for the electroweak production of two jets in association with a Z boson. These measurements are sensitive to the vector-boson fusion production mechanism and provide a fundamental test of the gauge structure of the Standard Model. The analysis is performed using proton–proton collision data collected by ATLAS at $$\sqrt{s}=13\ \hbox {TeV}$$ and with an integrated luminosity of $$139\ \hbox {fb}^{-1}$$. The Differential Cross-sections are measured in the $$Z\rightarrow \ell ^+\ell ^-$$ decay channel ($$\ell =e,\mu $$) as a function of four observables: the dijet invariant mass, the rapidity interval spanned by the two jets, the signed azimuthal angle between the two jets, and the transverse momentum of the dilepton pair. The data are corrected for the effects of detector inefficiency and resolution and are sufficiently precise to distinguish between different state-of-the-art theoretical predictions calculated using Powheg+Pythia
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Differential Cross section measurements for the electroweak production of dijets in association with a z boson in proton proton collisions at atlas
2020Co-Authors: G. Aad, A Kupco, Jay Chan, Timo Dreyer, Yufeng Wang, K Jakobs, Martin Spousta, M Cobal, Peilong Wang, S SchmittAbstract:Differential Cross-section measurements are presented for the electroweak production of two jets in association with a $Z$ boson. These measurements are sensitive to the vector-boson fusion production mechanism and provide a fundamental test of the gauge structure of the Standard Model. The analysis is performed using proton-proton collision data collected by ATLAS at $\sqrt{s}$=13 TeV and with an integrated luminosity of 139 fb$^{-1}$. The Differential Cross-sections are measured in the $Z\rightarrow \ell^+\ell^-$ decay channel ($\ell=e,\mu$) as a function of four observables: the dijet invariant mass, the rapidity interval spanned by the two jets, the signed azimuthal angle between the two jets, and the transverse momentum of the dilepton pair. The data are corrected for the effects of detector inefficiency and resolution and are sufficiently precise to distinguish between different state-of-the-art theoretical predictions calculated using Powheg+Pythia8, Herwig7+Vbfnlo and Sherpa 2.2. The Differential Cross-sections are used to search for anomalous weak-boson self-interactions using a dimension-six effective field theory. The measurement of the signed azimuthal angle between the two jets is found to be particularly sensitive to the interference between the Standard Model and dimension-six scattering amplitudes and provides a direct test of charge-conjugation and parity invariance in the weak-boson self-interactions.
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measurement of Differential Cross sections of a single top quark produced in association with a w boson at s 13tev with atlas
European Physical Journal C, 2018Co-Authors: M Aaboud, G. Aad, B. Abbott, S. H. Abidi, O Abdinov, B Abeloos, S Alderweireldt, S Caron, L Colasurdo, N De GrootAbstract:The Differential Cross-section for the production of a W boson in association with a top quark is measured for several particle-level observables. The measurements are performed using 36.1fb-1 of pp collision data collected with the ATLAS detector at the LHC in 2015 and 2016. Differential Cross-sections are measured in a fiducial phase space defined by the presence of two charged leptons and exactly one jet matched to a b-hadron, and are normalised with the fiducial Cross-section. Results are found to be in good agreement with predictions from several Monte Carlo event generators.
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measurement of Differential Cross sections of isolated photon plus heavy flavour jet production in pp collisions at s 8 tev using the atlas detector
Physics Letters B, 2018Co-Authors: M Aaboud, G. Aad, B. Abbott, S. H. Abidi, O. S. Abouzeid, N. L. Abraham, H. Abramowicz, O Abdinov, B Abeloos, H AbreuAbstract:This Letter presents the measurement of Differential Cross sections of isolated prompt photons produced in association with a b-jet or a c-jet. These final states provide sensitivity to the heavy-f ...
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measurement of the high mass drell yan Differential Cross section in pp collisions at root s 7 tev with the atlas detector
Physics Letters B, 2013Co-Authors: G. Aad, J Abdallah, B. Abbott, T Abajyan, Abdel S Khalek, A A Abdelalim, O Abdinov, R Aben, B Abi, M AbolinsAbstract:This Letter reports a measurement of the high-mass Drell–Yan Differential Cross-section in proton–proton collisions at a centre-of-mass energy of 7 TeV at the LHC. Based on an integrated luminosity ...