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  • E4: From MeV to TeV. Extracting the spectrum of cosmic rays at their sources over 6 orders of magnitude in energy | UnivEarthS
    currently available data the spectrum of cosmic rays at their acceleration sites over more than six orders of magnitude in energy from the MeV to the multi TeV domain This task impracticable until very recently is now possible due to unprecedented observations of supernova remnants in both the millimetre and gamma ray domains of the electromagnetic spectrum and will constitute a crucial step towards the solution of the problem of the origin of Galactic cosmic rays Very recent observations in the near infrared and millimetre domain made possible to measure the Cosmic Ray CR ionisation rate in a handful of Molecular Clouds MC located next to SuperNova Remnants SNR In all these cases the SNR shock is interacting with the MC The ionization rates found in this way are significantly enhanced up to a factor of 100 with respect to the average value found in isolated MCs Ceccarelli et al 2011 Vaupre et al 2014 This striking difference is interpreted as an evidence for a strongly enhanced intensity of MeV CRs in those MCs which are interacting with SNRs Moreover the same clouds from which enhanced ionization rates have been inferred have been also detected in gamma rays see e g Rieger et al 2013 That also requires an enhancement in the CR intensity though in this case particles with much larger energies up to 10 100 TeV have to be invoked Both these facts provide a strong support to the popular but not conclusively proven yet conjecture that SNRs are the sources of CRs The goal of the proposed research is to combine these two observables and after complementing them with thorough and original theoretical investigations obtain information on the spectrum of CRs at their presumed sources within a huge interval spanning more than six orders of magnitude in

    Original URL path: http://www.univearths.fr/en/mev-to-tev?quicktabs_menu_e4_en=0 (2015-10-10)
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  • Workshop : Cosmic Rays from MeV to TeV Energies | UnivEarthS
    Universe Interface projects Geoparticles Fundamental physics and Geophysics in space From dust to planets Former Interface projects Formation and early evolution of Planetary systems The youth of cosmic rays and their emergence in the interstellar clouds Gamma ray instrumentation development Young team project Experimental geophysics Valorization project Data distribution visualisation and cloud computing PUBLICATIONS EDUCATIONAL Nanosatellite student project IGOsat UnivEarthS JOB OPPORTUNITY Experimental Dark Matter Search Post Doctoral Research Fellow

    Original URL path: http://www.univearths.fr/en/workshop-cosmic-rays-mev-tev-energies (2015-10-10)
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  • E5: Numerical Observatory of Violent Accretion systems NOVAs strong gravity and beyond | UnivEarthS
    in the close neighborhood of compact objects is only properly described in the framework of general relativistic magnetohydrodynamic GR MHD The equations governing GR MHD are so complex that the only way to solve them is trough large scale numerical simulations The topic of the present demand is to sustain a computational effort dedicated to GRMHD simulations of accretion flows near compact objects and to link them to synthetic observations of the associated violent events one of the major themes within LabeX UnivEarths General Objective of the Project The quest to unveil the nature of the compact objects detected in the center of radio loud galaxies in X ray binaries and also at the center of the Milky Way is at the crossroads between high resolution time dependent multi wavelength observations and the coming of age of numerical GR MHD codes The project presented here plans to exploit this opportunity by setting a long standing collaboration between members of three teams involved in the LabeX UnivEarths which are already tackling individually the problem from the different angles of analytical and numerical studies observations and high performance code development While the french community is at the moment lacking a numerical code able to describe the dynamics of a magnetized plasma in a full GR framework the LabeX UnivEarths benefits from a unique conjunction where plasma numericists high energy observers and GR numericists are present in the same area and have had a good track record on common past projects By joining forces our aim is to sustain the development of such a GR MHD code in order to perform large scale simulations of plasma accretion onto compact objects and subsequently create an observation from it Another innovative feature of our code will stem from its ability to handle any kind of GR metrics not only conventional metric such as Schwarzschild or Kerr but also metrics of alternative non GR gravitation theories which generally do not have any analytical expression The three teams and interaction Our team while approaching a new subject linking their respective research is composed of people used to working together on a variety of topics such as GRBs and planet formation For this project we plan on using our distinct approaches to tackle the creation the first full GR MHD code coupled to a ray tracing code able to provide synthetic observations of the environment of compact objects AIM high energy observers axis led by J Rodriguez They are expert of multi wavelengths observations of compact objects and have access through dedicated and collaborative programs to a wide range of observations This broad range of data have allowed them to tackle the problems of accretion ejection connections and mechanisms prevailing in those systems including also the study of rapid X ray variability APC ADAMIS simulation axis led by F Casse and P Varniere Their expertise ranges from analytical to MHD numerical studies of the accretion ejection system They also do the extra step of linking their results with

    Original URL path: http://www.univearths.fr/en/e5-numerical-observatory-violent-accretion-systems-novas-strong-gravity-and-beyond?mini=node%2F333%2F2015-09 (2015-10-10)
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  • E5: Numerical Observatory of Violent Accretion systems NOVAs strong gravity and beyond | UnivEarthS
    in the close neighborhood of compact objects is only properly described in the framework of general relativistic magnetohydrodynamic GR MHD The equations governing GR MHD are so complex that the only way to solve them is trough large scale numerical simulations The topic of the present demand is to sustain a computational effort dedicated to GRMHD simulations of accretion flows near compact objects and to link them to synthetic observations of the associated violent events one of the major themes within LabeX UnivEarths General Objective of the Project The quest to unveil the nature of the compact objects detected in the center of radio loud galaxies in X ray binaries and also at the center of the Milky Way is at the crossroads between high resolution time dependent multi wavelength observations and the coming of age of numerical GR MHD codes The project presented here plans to exploit this opportunity by setting a long standing collaboration between members of three teams involved in the LabeX UnivEarths which are already tackling individually the problem from the different angles of analytical and numerical studies observations and high performance code development While the french community is at the moment lacking a numerical code able to describe the dynamics of a magnetized plasma in a full GR framework the LabeX UnivEarths benefits from a unique conjunction where plasma numericists high energy observers and GR numericists are present in the same area and have had a good track record on common past projects By joining forces our aim is to sustain the development of such a GR MHD code in order to perform large scale simulations of plasma accretion onto compact objects and subsequently create an observation from it Another innovative feature of our code will stem from its ability to handle any kind of GR metrics not only conventional metric such as Schwarzschild or Kerr but also metrics of alternative non GR gravitation theories which generally do not have any analytical expression The three teams and interaction Our team while approaching a new subject linking their respective research is composed of people used to working together on a variety of topics such as GRBs and planet formation For this project we plan on using our distinct approaches to tackle the creation the first full GR MHD code coupled to a ray tracing code able to provide synthetic observations of the environment of compact objects AIM high energy observers axis led by J Rodriguez They are expert of multi wavelengths observations of compact objects and have access through dedicated and collaborative programs to a wide range of observations This broad range of data have allowed them to tackle the problems of accretion ejection connections and mechanisms prevailing in those systems including also the study of rapid X ray variability APC ADAMIS simulation axis led by F Casse and P Varniere Their expertise ranges from analytical to MHD numerical studies of the accretion ejection system They also do the extra step of linking their results with

    Original URL path: http://www.univearths.fr/en/e5-numerical-observatory-violent-accretion-systems-novas-strong-gravity-and-beyond?mini=node%2F333%2F2015-11 (2015-10-10)
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  • E5: Numerical Observatory of Violent Accretion systems NOVAs strong gravity and beyond | UnivEarthS
    plasma in the close neighborhood of compact objects is only properly described in the framework of general relativistic magnetohydrodynamic GR MHD The equations governing GR MHD are so complex that the only way to solve them is trough large scale numerical simulations The topic of the present demand is to sustain a computational effort dedicated to GRMHD simulations of accretion flows near compact objects and to link them to synthetic observations of the associated violent events one of the major themes within LabeX UnivEarths General Objective of the Project The quest to unveil the nature of the compact objects detected in the center of radio loud galaxies in X ray binaries and also at the center of the Milky Way is at the crossroads between high resolution time dependent multi wavelength observations and the coming of age of numerical GR MHD codes The project presented here plans to exploit this opportunity by setting a long standing collaboration between members of three teams involved in the LabeX UnivEarths which are already tackling individually the problem from the different angles of analytical and numerical studies observations and high performance code development While the french community is at the moment lacking a numerical code able to describe the dynamics of a magnetized plasma in a full GR framework the LabeX UnivEarths benefits from a unique conjunction where plasma numericists high energy observers and GR numericists are present in the same area and have had a good track record on common past projects By joining forces our aim is to sustain the development of such a GR MHD code in order to perform large scale simulations of plasma accretion onto compact objects and subsequently create an observation from it Another innovative feature of our code will stem from its ability to handle any kind of GR metrics not only conventional metric such as Schwarzschild or Kerr but also metrics of alternative non GR gravitation theories which generally do not have any analytical expression The three teams and interaction Our team while approaching a new subject linking their respective research is composed of people used to working together on a variety of topics such as GRBs and planet formation For this project we plan on using our distinct approaches to tackle the creation the first full GR MHD code coupled to a ray tracing code able to provide synthetic observations of the environment of compact objects AIM high energy observers axis led by J Rodriguez They are expert of multi wavelengths observations of compact objects and have access through dedicated and collaborative programs to a wide range of observations This broad range of data have allowed them to tackle the problems of accretion ejection connections and mechanisms prevailing in those systems including also the study of rapid X ray variability APC ADAMIS simulation axis led by F Casse and P Varniere Their expertise ranges from analytical to MHD numerical studies of the accretion ejection system They also do the extra step of linking their results

    Original URL path: http://www.univearths.fr/en/e5-numerical-observatory-violent-accretion-systems-novas-strong-gravity-and-beyond?quicktabs_menu_e5_en=0 (2015-10-10)
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  • The new cluster arrived at FACEe | UnivEarthS
    future Universe Support au PCCP The transient catastrophic Universe Interface projects Geoparticles Fundamental physics and Geophysics in space From dust to planets Former Interface projects Formation and early evolution of Planetary systems The youth of cosmic rays and their emergence in the interstellar clouds Gamma ray instrumentation development Young team project Experimental geophysics Valorization project Data distribution visualisation and cloud computing PUBLICATIONS EDUCATIONAL Nanosatellite student project IGOsat UnivEarthS JOB OPPORTUNITY

    Original URL path: http://www.univearths.fr/en/new-cluster-arrived-facee (2015-10-10)
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  • French Astrophysics Week | UnivEarthS
    transient catastrophic Universe Interface projects Geoparticles Fundamental physics and Geophysics in space From dust to planets Former Interface projects Formation and early evolution of Planetary systems The youth of cosmic rays and their emergence in the interstellar clouds Gamma ray instrumentation development Young team project Experimental geophysics Valorization project Data distribution visualisation and cloud computing PUBLICATIONS EDUCATIONAL Nanosatellite student project IGOsat UnivEarthS JOB OPPORTUNITY Experimental Dark Matter Search Post Doctoral

    Original URL path: http://www.univearths.fr/en/french-astrophysics-week (2015-10-10)
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  • E6: Gamma-Ray Bursts as Multi-messengers | UnivEarthS
    but a direct proof of this model is still lacking The high energy part of the GRB spectrum The observation by the Fermi LAT of several GRB photons with energies reaching 50 100 GeV in the source frame is an encouraging sign for GRB detections with the next generation of instruments operating in the GeV and TeV domain The extrapolation of Fermi LAT spectral measurements to the VHE domain is difficult due to the limited knowledge of GRB properties at these energies see Gehrels Razzaque Frontiers of Physics 2013 In particular it remains unclear whether the hard component observed in the spectra of several bright Fermi GRBs is a common property at GeV energies In addition intrinsic spectral cut offs similar to the case of GRB 090926A are expected at 1 100 GeV energies and are strongly related to the value of the GRB jet Lorentz factor For these reasons current estimates of the GRB detection rate by future TeV experiments like CTA suffer from important uncertainties and range from 0 5 to 2 GRBs per year Inoue et al Astropart Phys 43 252 2013 Nonetheless during the lifetime of SVOM a few but invaluable GRB detections are thus expected in the 0 05 0 5 TeV range from CTA especially in the light of the recent bright GeV afterglow detected for GRB 130427A Tam et al ApJ 77 L13 2013 Joint time resolved spectral analyses based on SVOM and CTA data will also help to pinpoint the acceleration and emission processes occurring in GRB jets Studies of the GRB prompt emission phase from sub MeV to sub TeV energies can help to distinguish between leptonic and hadronic models and to investigate the possibility of GRBs being a source of ultra high energy cosmic rays and answer the long standing question of the origin of the cosmic rays observed on Earth with energies larger than 10 10 GeV GRBs and the new messengers To date neutrino and gravitational wave signals detected by current experiments could not be correlated with any precise astrophysical source Thanks to their short duration and their high flux GRBs are the best electromagnetic counterpart candidates and a simultaneous detection would represent the start of a new era for those two research fields namely the astronomy era Neutrinos Neutrinos are unique messengers to study the high energy Universe as they are neutral and stable interact weakly and therefore travel directly from their point of creation to the Earth without absorption Neutrinos could play an important role in understanding the mechanisms of cosmic ray acceleration and their detection from a cosmic source would be a direct evidence of the presence of hadronic acceleration Indeed HE neutrinos are produced in a beam dump scenario via meson mainly pion π decay when the accelerated hadrons protons or nuclei interact with ambient matter or dense photon fields The emitted neutrinos typically have an energy which is about 10 of the energy of the interacting protons The production of neutrinos of 10

    Original URL path: http://www.univearths.fr/en/e6-gamma-ray-bursts-multi-messengers?mini=node%2F333%2F2015-09 (2015-10-10)
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