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J. C. Raymond - One of the best experts on this subject based on the ideXlab platform.
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efficient cosmic ray acceleration hydrodynamics and self consistent thermal x ray Emission applied to supernova remnant rx j1713 7 3946
The Astrophysical Journal, 2010Co-Authors: Donald C. Ellison, Daniel J Patnaude, Patrick Slane, J. C. RaymondAbstract:We model the broadband Emission from supernova remnant (SNR) RX J1713.7-3946 including, for the first time, a consistent calculation of thermal X-Ray Emission together with non-thermal Emission in a nonlinear diffusive shock acceleration model. Our model tracks the evolution of the SNR including the plasma ionization state between the forward shock and the contact discontinuity. We use a plasma emissivity code to predict the thermal X-Ray Emission Spectrum assuming the initially cold electrons are heated either by Coulomb collisions with the shock-heated protons (the slowest possible heating), or come into instant equilibration with the protons. For either electron heating model, electrons reach 107 K rapidly and the X-Ray line Emission near 1 keV is more than 10 times as luminous as the underlying thermal bremsstrahlung continuum. Since recent Suzaku observations show no detectable line Emission, this places strong constraints on the unshocked ambient medium density and on the relativistic electron-to-proton ratio. For the uniform circumstellar medium (CSM) models that we consider, the low densities and high relativistic electron-to-proton ratios required to match the Suzaku X-Ray observations definitively rule out pion decay as the Emission process producing GeV-TeV photons. We show that leptonic models, where inverse-Compton scattering against the cosmic background radiation dominates the GeV-TeV Emission, produce better fits to the broadband thermal and non-thermal observations in a uniform CSM.
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efficient cosmic ray acceleration hydrodynamics and self consistent thermal x ray Emission applied to snr rx j1713 7 3946
arXiv: High Energy Astrophysical Phenomena, 2010Co-Authors: Donald C. Ellison, Daniel J Patnaude, Patrick Slane, J. C. RaymondAbstract:We model the broad-band Emission from SNR RX J1713.7-3946 including, for the first time, a consistent calculation of thermal X-Ray Emission together with non-thermal Emission in a nonlinear diffusive shock acceleration (DSA) model. Our model tracks the evolution of the SNR including the plasma ionization state between the forward shock and the contact discontinuity. We use a plasma emissivity code to predict the thermal X-Ray Emission Spectrum assuming the initially cold electrons are heated either by Coulomb collisions with the shock heated protons (the slowest possible heating), or come into instant equilibration with the protons. For either electron heating model, electrons reach >10^7 K rapidly and the X-Ray line Emission near 1 keV is more than 10 times as luminous as the underlying thermal bremsstrahlung continuum. Since recent Suzaku observations show no detectable line Emission, this places strong constraints on the unshocked ambient medium density and on the relativistic electron to proton ratio. For the uniform circumstellar medium (CSM) models we consider, the low densities and high relativistic electron to proton ratios required to match the Suzaku X-Ray observations definitively rule out pion-decay as the Emission process producing GeV-TeV photons. We show that leptonic models, where inverse-Compton scattering against the cosmic background radiation dominates the GeV-TeV Emission, produce better fits to the broad-band thermal and non-thermal observations in a uniform CSM.
Lars G. M. Pettersson - One of the best experts on this subject based on the ideXlab platform.
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Core-hole-induced dynamical effects in the X-Ray Emission Spectrum of liquid methanol
The Journal of chemical physics, 2017Co-Authors: Mathias P. Ljungberg, Iurii Zhovtobriukh, Osamu Takahashi, Lars G. M. PetterssonAbstract:We compute the X-Ray Emission Spectrum of liquid methanol, with the dynamical effects that result from the creation of the core hole included in a semiclassical way. Our method closely reproduces a fully quantum mechanical description of the dynamical effects for relevant one-dimensional models of the hydrogen-bonded methanol molecules. For the liquid, we find excellent agreement with the experimental Spectrum, including the large isotope effect in the first split peak. The dynamical effects depend sensitively on the initial structure in terms of the local hydrogen-bonding (H-bonding) character: non-donor molecules contribute mainly to the high-energy peak while molecules with a strong donating H-bond contribute to the peak at lower energy. The Spectrum thus reflects the initial structure mediated by the dynamical effects that are, however, seen to be crucial in order to reproduce the intensity distribution of the recently measured Spectrum.
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core hole induced dynamical effects in the x ray Emission Spectrum of liquid methanol
arXiv: Materials Science, 2017Co-Authors: Mathias P. Ljungberg, Iurii Zhovtobriukh, Osamu Takahashi, Lars G. M. PetterssonAbstract:We compute the X-Ray Emission Spectrum (XES) of liquid methanol, with the dynamical effects that result from the creation of the core hole included in a semiclassical way. Our method closely reproduces a fully quantum mechanical description of the dynamical effects for relevant one-dimensional models of the hydrogen-bonded methanol molecules. For the liquid we find excellent agreement with the experimental Spectrum, including the large isotope effect in the first split peak. The dynamical effects depend sensitively on the initial structure in terms of the local hydrogen-bonding (H-bonding) character; non-donor molecules contribute mainly to the high-energy peak while molecules with a strong donated H-bond contribute to the peak at lower energy. The Spectrum thus reflects the initial structure mediated by the dynamical effects that are, however, seen to be crucial in order to reproduce the intensity distribution of the recently measured Spectrum.
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vibrational interference effects in x ray Emission of a model water dimer implications for the interpretation of the liquid Spectrum
Journal of Chemical Physics, 2011Co-Authors: Mathias P. Ljungberg, Lars G. M. Pettersson, Anders NilssonAbstract:We apply the Kramers–Heisenberg formula to a model water dimer to discuss vibrational interference in the X-Ray Emission Spectrum of the donor molecule for which the core-ionized potential energy surface is dissociative but bounded by the accepting molecule. A long core–hole lifetime leads to decay from Zundel-like, fully delocalized vibrational states in the intermediate potential without involvement of a specific dissociated component. Comparison is made to a model with an unbound intermediate state allowing dissociation to infinity which gives a sharp, fully dissociated feature, and a broad molecular peak at long core–hole life time. The implications of the vibrational interference effect on the liquid water Spectrum are discussed and it is proposed that this mainly gives rise to an isotope-dependent asymmetrical broadening of the lone pair peak.
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a simple picture of x ray Emission of condensed phase water
2010Co-Authors: Mathias P. Ljungberg, Lars G. M. Pettersson, Anders NilssonAbstract:We apply the Kramers-Heisenberg formula to a one-dimensional model of the water dimer to discuss vibrational interference in the X-Ray Emission Spectrum of the donor molecule for which the core-ion ...
Mathias P. Ljungberg - One of the best experts on this subject based on the ideXlab platform.
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Core-hole-induced dynamical effects in the X-Ray Emission Spectrum of liquid methanol
The Journal of chemical physics, 2017Co-Authors: Mathias P. Ljungberg, Iurii Zhovtobriukh, Osamu Takahashi, Lars G. M. PetterssonAbstract:We compute the X-Ray Emission Spectrum of liquid methanol, with the dynamical effects that result from the creation of the core hole included in a semiclassical way. Our method closely reproduces a fully quantum mechanical description of the dynamical effects for relevant one-dimensional models of the hydrogen-bonded methanol molecules. For the liquid, we find excellent agreement with the experimental Spectrum, including the large isotope effect in the first split peak. The dynamical effects depend sensitively on the initial structure in terms of the local hydrogen-bonding (H-bonding) character: non-donor molecules contribute mainly to the high-energy peak while molecules with a strong donating H-bond contribute to the peak at lower energy. The Spectrum thus reflects the initial structure mediated by the dynamical effects that are, however, seen to be crucial in order to reproduce the intensity distribution of the recently measured Spectrum.
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core hole induced dynamical effects in the x ray Emission Spectrum of liquid methanol
arXiv: Materials Science, 2017Co-Authors: Mathias P. Ljungberg, Iurii Zhovtobriukh, Osamu Takahashi, Lars G. M. PetterssonAbstract:We compute the X-Ray Emission Spectrum (XES) of liquid methanol, with the dynamical effects that result from the creation of the core hole included in a semiclassical way. Our method closely reproduces a fully quantum mechanical description of the dynamical effects for relevant one-dimensional models of the hydrogen-bonded methanol molecules. For the liquid we find excellent agreement with the experimental Spectrum, including the large isotope effect in the first split peak. The dynamical effects depend sensitively on the initial structure in terms of the local hydrogen-bonding (H-bonding) character; non-donor molecules contribute mainly to the high-energy peak while molecules with a strong donated H-bond contribute to the peak at lower energy. The Spectrum thus reflects the initial structure mediated by the dynamical effects that are, however, seen to be crucial in order to reproduce the intensity distribution of the recently measured Spectrum.
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vibrational interference effects in x ray Emission of a model water dimer implications for the interpretation of the liquid Spectrum
Journal of Chemical Physics, 2011Co-Authors: Mathias P. Ljungberg, Lars G. M. Pettersson, Anders NilssonAbstract:We apply the Kramers–Heisenberg formula to a model water dimer to discuss vibrational interference in the X-Ray Emission Spectrum of the donor molecule for which the core-ionized potential energy surface is dissociative but bounded by the accepting molecule. A long core–hole lifetime leads to decay from Zundel-like, fully delocalized vibrational states in the intermediate potential without involvement of a specific dissociated component. Comparison is made to a model with an unbound intermediate state allowing dissociation to infinity which gives a sharp, fully dissociated feature, and a broad molecular peak at long core–hole life time. The implications of the vibrational interference effect on the liquid water Spectrum are discussed and it is proposed that this mainly gives rise to an isotope-dependent asymmetrical broadening of the lone pair peak.
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a simple picture of x ray Emission of condensed phase water
2010Co-Authors: Mathias P. Ljungberg, Lars G. M. Pettersson, Anders NilssonAbstract:We apply the Kramers-Heisenberg formula to a one-dimensional model of the water dimer to discuss vibrational interference in the X-Ray Emission Spectrum of the donor molecule for which the core-ion ...
Donald C. Ellison - One of the best experts on this subject based on the ideXlab platform.
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efficient cosmic ray acceleration hydrodynamics and self consistent thermal x ray Emission applied to supernova remnant rx j1713 7 3946
The Astrophysical Journal, 2010Co-Authors: Donald C. Ellison, Daniel J Patnaude, Patrick Slane, J. C. RaymondAbstract:We model the broadband Emission from supernova remnant (SNR) RX J1713.7-3946 including, for the first time, a consistent calculation of thermal X-Ray Emission together with non-thermal Emission in a nonlinear diffusive shock acceleration model. Our model tracks the evolution of the SNR including the plasma ionization state between the forward shock and the contact discontinuity. We use a plasma emissivity code to predict the thermal X-Ray Emission Spectrum assuming the initially cold electrons are heated either by Coulomb collisions with the shock-heated protons (the slowest possible heating), or come into instant equilibration with the protons. For either electron heating model, electrons reach 107 K rapidly and the X-Ray line Emission near 1 keV is more than 10 times as luminous as the underlying thermal bremsstrahlung continuum. Since recent Suzaku observations show no detectable line Emission, this places strong constraints on the unshocked ambient medium density and on the relativistic electron-to-proton ratio. For the uniform circumstellar medium (CSM) models that we consider, the low densities and high relativistic electron-to-proton ratios required to match the Suzaku X-Ray observations definitively rule out pion decay as the Emission process producing GeV-TeV photons. We show that leptonic models, where inverse-Compton scattering against the cosmic background radiation dominates the GeV-TeV Emission, produce better fits to the broadband thermal and non-thermal observations in a uniform CSM.
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efficient cosmic ray acceleration hydrodynamics and self consistent thermal x ray Emission applied to snr rx j1713 7 3946
arXiv: High Energy Astrophysical Phenomena, 2010Co-Authors: Donald C. Ellison, Daniel J Patnaude, Patrick Slane, J. C. RaymondAbstract:We model the broad-band Emission from SNR RX J1713.7-3946 including, for the first time, a consistent calculation of thermal X-Ray Emission together with non-thermal Emission in a nonlinear diffusive shock acceleration (DSA) model. Our model tracks the evolution of the SNR including the plasma ionization state between the forward shock and the contact discontinuity. We use a plasma emissivity code to predict the thermal X-Ray Emission Spectrum assuming the initially cold electrons are heated either by Coulomb collisions with the shock heated protons (the slowest possible heating), or come into instant equilibration with the protons. For either electron heating model, electrons reach >10^7 K rapidly and the X-Ray line Emission near 1 keV is more than 10 times as luminous as the underlying thermal bremsstrahlung continuum. Since recent Suzaku observations show no detectable line Emission, this places strong constraints on the unshocked ambient medium density and on the relativistic electron to proton ratio. For the uniform circumstellar medium (CSM) models we consider, the low densities and high relativistic electron to proton ratios required to match the Suzaku X-Ray observations definitively rule out pion-decay as the Emission process producing GeV-TeV photons. We show that leptonic models, where inverse-Compton scattering against the cosmic background radiation dominates the GeV-TeV Emission, produce better fits to the broad-band thermal and non-thermal observations in a uniform CSM.
Tortosa A. - One of the best experts on this subject based on the ideXlab platform.
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The soft excess of the NLS1 galaxy Mrk 359 studied with an XMM-Newton - NuSTAR monitoring campaign
'EDP Sciences', 2020Co-Authors: Middei R., Petrucci Pierre-olivier, Bianchi S., Ursini F., Cappi M., Clavel M., De Rosa A., Marinucci A., Matt G., Tortosa A.Abstract:International audienceContext. Joint XMM-Newton and NuSTAR multiple exposures allow us to disentangle the different Emission components of active galactic nuclei (AGNs) and to study the evolution of their different spectral features. In this work, we present the timing and spectral properties of five simultaneous XMM-NewtonandNuSTAR observations of the Narrow Line Seyfert 1 galaxy Mrk 359. Aims: We aim to provide the first broadband spectral modeling of Mrk 359 describing its Emission Spectrum from the UV up to the hard X-Rays. Methods: We performed temporal and spectral data analysis, characterising the amplitude and spectral changes of the Mrk 359 time series and computing the 2-10 keV normalised excess variance. The spectral broadband modelling assumes the standard hot Comptonising corona and reflection component, while for the soft excess we tested two different models: a warm, optically thick Comptonising corona (the two-corona model) and a reflection model in which the soft-excess is the result of a blurred reflected continuum and line Emission (the reflection model). Results: High and low flux states were observed during the campaign. The former state has a softer spectral shape, while the latter shows a harder one. The photon index is in the 1.75-1.89 range, and only a lower limit to the hot-corona electron temperature can be found. A constant reflection component, likely associated with distant matter, is observed. Regarding the soft excess, we found that among the reflection models we tested, the one providing the better fit (reduced χ2 = 1.14) is the high-density one. However, a significantly better fit (reduced χ2 = 1.08) is found by modelling the soft excess with a warm Comptonisation model. Conclusions: The present analysis suggests the two-corona model as the best scenario for the optical-UV to X-Ray Emission Spectrum of Mrk 359
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The soft excess of the NLS1 galaxy Mrk 359 studied with an XMM-Newton-NuSTAR monitoring campaign
'EDP Sciences', 2020Co-Authors: Middei R., Bianchi S., Ursini F., Cappi M., Clavel M., De Rosa A., Marinucci A., Matt G., Petrucci P. -o., Tortosa A.Abstract:XMM-Newton and NuSTAR multiple exposures allow us to disentangle the different Emission components of active galactic nuclei (AGNs) and to study the evolution of their different spectral features. In this work, we present the timing and spectral properties of five simultaneous XMM-Newton and NuSTAR observations of the Narrow Line Seyfert 1 galaxy Mrk 359. We aim to provide the first broadband spectral modeling of Mrk 359 describing its Emission Spectrum from the UV up to the hard X-Rays. To do this, we performed temporal and spectral data analysis, characterising the amplitude and spectral changes of the Mrk 359 time series and computing the 2-10 keV normalised excess variance. The spectral broadband modelling assumes the standard hot Comptonising corona and reflection component, while for the soft excess we tested two different models: a warm, optically thick Comptonising corona (the two-corona model) and a reflection model in which the soft-excess is the result of a blurred reflected continuum and line Emission (the reflection model). High and low flux states were observed during the campaign. The former state has a softer spectral shape, while the latter shows a harder one. The photon index is in the 1.75-1.89 range, and only a lower limit to the hot-corona electron temperature can be found. A constant reflection component, likely associated with distant matter, is observed. Regarding the soft excess, we found that among the reflection models we tested, the one providing the better fit (reduced $\chi^2$=1.14) is the high-density one. However, a significantly better fit (reduced $\chi^2$=1.08) is found by modelling the soft excess with a warm Comptonisation model. The present analysis suggests the two-corona model as the best scenario for the optical-UV to X-Ray Emission Spectrum of Mrk 359.Comment: 12 pages, 14 figures. Accepted for publication in A&
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The soft excess of the NLS1 galaxy Mrk 359 studied with an XMM-Newton-NuSTAR monitoring campaign
'EDP Sciences', 2020Co-Authors: Middei R., Bianchi S., Ursini F., Cappi M., Clavel M., De Rosa A., Marinucci A., Matt G., Petrucci P.o., Tortosa A.Abstract:International audienceContext. Joint XMM-Newton and NuSTAR multiple exposures allow us to disentangle the different Emission components of active galactic nuclei (AGNs) and to study the evolution of their different spectral features. In this work, we present the timing and spectral properties of five simultaneous XMM-NewtonandNuSTAR observations of the Narrow Line Seyfert 1 galaxy Mrk 359.Aims. We aim to provide the first broadband spectral modeling of Mrk 359 describing its Emission Spectrum from the UV up to the hard X-Rays.Methods. We performed temporal and spectral data analysis, characterising the amplitude and spectral changes of the Mrk 359 time series and computing the 2–10 keV normalised excess variance. The spectral broadband modelling assumes the standard hot Comptonising corona and reflection component, while for the soft excess we tested two different models: a warm, optically thick Comptonising corona (the two-corona model) and a reflection model in which the soft-excess is the result of a blurred reflected continuum and line Emission (the reflection model).Results. High and low flux states were observed during the campaign. The former state has a softer spectral shape, while the latter shows a harder one. The photon index is in the 1.75–1.89 range, and only a lower limit to the hot-corona electron temperature can be found. A constant reflection component, likely associated with distant matter, is observed. Regarding the soft excess, we found that among the reflection models we tested, the one providing the better fit (reduced χ2 = 1.14) is the high-density one. However, a significantly better fit (reduced χ2 = 1.08) is found by modelling the soft excess with a warm Comptonisation model.Conclusions. The present analysis suggests the two-corona model as the best scenario for the optical-UV to X-Ray Emission Spectrum of Mrk 359.Key words: galaxies: active / galaxies: Seyfert / X-Rays: galaxies / X-Rays: individuals: Mrk 35
