The Experts below are selected from a list of 9 Experts worldwide ranked by ideXlab platform
Elena Orlando - One of the best experts on this subject based on the ideXlab platform.
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A Consistent Model of the Interstellar Gamma-Ray Emission to Interpret Fermi LAT Observations of Diffuse Emissions
2019Co-Authors: Elena OrlandoAbstract:Cosmic rays interacting with gas and photons in the Galaxy produce Interstellar gamma-ray Emission, which accounts for most of the photons detected at gamma-ray energies. Models of this Interstellar gamma-ray Emission have to be very accurate for interpreting the high-quality observations by Fermi Large Area Telescope (LAT). Standard models, used as reference models for analyses of the Fermi LAT data, show spatial discrepancies with respect to the data, underlining the necessity of more realistic models. We show that cosmic-ray propagation models that account for observations of the Interstellar Synchrotron Emission in radio and microwave produce spatial and spectral distributions of the large-scale inverse-Compton component of the Interstellar gamma-ray Emission significantly different from the ones usually used in studies of Fermi LAT data. For example, models based on Synchrotron observations produce a more peaked inverse-Compton Emission in the inner Galaxy with respect to the standard models used to analyze Fermi LAT data. This paper discusses the results based on Orlando (2019) Physical Review D 99, 043007 and Orlando (2018) MNRAS 475, 2724. Details are reported in those papers. The author acknowledges support from NASA Grants No. NNX16AF27G.
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implications on spatial models of Interstellar gamma ray inverse compton Emission from Synchrotron Emission studies in radio and microwaves
Physical Review D, 2019Co-Authors: Elena OrlandoAbstract:Cosmic rays interacting with gas and photon fields in the Galaxy produce Interstellar gamma-ray Emission (IGE), which accounts for almost 50% of the photons detected at gamma-ray energies. Models of this IGE have to be very accurate for interpreting the high-quality observations by present gamma-ray telescopes, such as Fermi Large Area Telescope (LAT). Standard models of IGE, used as reference models for analyses of the Fermi LAT data, show spatial discrepancies with respect to the data, underlining the necessity of more realistic models. The same CR electrons that produce the inverse-Compton component of the IGE produce also Interstellar Synchrotron Emission observed in radio and microwave. However, present standard models do not take advantage of results coming from studies of this Interstellar Synchrotron Emission. Accounting for such results, in this work we show how they affect the calculated spatial maps of the large-scale inverse-Compton component of the IGE, which are usually used in studies of Fermi LAT data. It is found that these results significantly affect these spatial model maps even at a 60% level. In particular, propagation models based on Synchrotron studies produce a more peaked inverse-Compton Emission in the inner Galaxy region with respect to the standard models used to analyze Fermi LAT data. The conclusion is that radio and microwave observations can be included in a multifrequency self-consistent approach for a more accurate modeling of the IGE finalized to a physical comprehensive interpretation of gamma-ray data and its present unexplained features. Model parameters are provided, which supply a more realistic basis for high-energy gamma-ray studies.
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cosmic ray leptons magnetic fields and Interstellar Synchrotron Emission
arXiv: Astrophysics of Galaxies, 2013Co-Authors: Elena Orlando, A W StrongAbstract:Interstellar Synchrotron Emission depends on Galactic magnetic fields and on cosmic-ray leptons. Observations of radio Emission are an important tool for studying cosmic-ray propagation models and Interstellar electron spectrum and distribution in the Galaxy. We present the latest developments in our modeling of Galactic Synchrotron Emission with the GALPROP code, including polarization, absorption, and free-free Emission. Using surveys over a wide range of radio frequencies and polarization measurements, we derive constraints on the low- energy Interstellar cosmic-ray electron spectrum, magnetic fields and cosmic-ray propagation models. This work is of interest for studies of Interstellar gamma-ray Emission with Fermi-LAT, and Synchrotron for the Planck mission.
A W Strong - One of the best experts on this subject based on the ideXlab platform.
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cosmic ray leptons magnetic fields and Interstellar Synchrotron Emission
arXiv: Astrophysics of Galaxies, 2013Co-Authors: Elena Orlando, A W StrongAbstract:Interstellar Synchrotron Emission depends on Galactic magnetic fields and on cosmic-ray leptons. Observations of radio Emission are an important tool for studying cosmic-ray propagation models and Interstellar electron spectrum and distribution in the Galaxy. We present the latest developments in our modeling of Galactic Synchrotron Emission with the GALPROP code, including polarization, absorption, and free-free Emission. Using surveys over a wide range of radio frequencies and polarization measurements, we derive constraints on the low- energy Interstellar cosmic-ray electron spectrum, magnetic fields and cosmic-ray propagation models. This work is of interest for studies of Interstellar gamma-ray Emission with Fermi-LAT, and Synchrotron for the Planck mission.
