I. V. Moskalenko
A5106227074- Astrophysics and Cosmic Phenomena
- Dark Matter and Cosmic Phenomena
- Gamma-ray bursts and supernovae
- Particle Detector Development and Performance
- Solar and Space Plasma Dynamics
- Radio Astronomy Observations and Technology
- Pulsars and Gravitational Waves Research
- Neutrino Physics Research
- Astrophysical Phenomena and Observations
- Particle physics theoretical and experimental studies
- Radiation Therapy and Dosimetry
- Galaxies: Formation, Evolution, Phenomena
- Astro and Planetary Science
- Atmospheric Ozone and Climate
- Atomic and Subatomic Physics Research
- Nuclear Physics and Applications
- Astronomical Observations and Instrumentation
- Cosmology and Gravitation Theories
- Astrophysics and Star Formation Studies
- Astronomy and Astrophysical Research
- Atomic and Molecular Physics
- Particle Accelerators and Free-Electron Lasers
- Radiation Detection and Scintillator Technologies
- Magnetic confinement fusion research
- Planetary Science and Exploration
Kavli Institute for Particle Astrophysics and Cosmology
2015-2024
Stanford University
2015-2024
SLAC National Accelerator Laboratory
2014-2023
Centre National de la Recherche Scientifique
2011-2023
Moscow State University of Geodesy and Cartography
2023
University of Iceland
2016-2023
Université Savoie Mont Blanc
2023
Laboratoire d'Annecy-le-Vieux de Physique Théorique
2023
Université Grenoble Alpes
2023
Institut National de Physique Nucléaire et de Physique des Particules
2023
We survey the theory and experimental tests for propagation of cosmic rays in Galaxy up to energies 10^15 eV. A guide previous reviews essential literature is given, followed by an exposition basic principles. The ideas cosmic-ray are described, physical origin its processes explained. various techniques computing observational consequences described contrasted. These include analytical numerical techniques. present comparison models with data including direct indirect - especially gamma-ray...
We describe a method for the numerical computation of propagation primary and secondary nucleons, electrons, positrons electrons. Fragmentation energy losses are computed using realistic distributions interstellar gas radiation fields, diffusive reacceleration is also incorporated. The models adjusted to agree with observed cosmic-ray B/C 10Be/9Be ratios. Models diffusion convection do not account well dependence B/C, while reproduce this easily. height halo region determined, recent...
The γ-ray sky can be decomposed into individually detected sources, diffuse emission attributed to the interactions of Galactic cosmic rays with gas and radiation fields, a residual all-sky component commonly called isotropic background (IGRB). IGRB comprises all extragalactic emissions too faint or resolved in given survey, as well any foregrounds that are approximately isotropic. first measurement Large Area Telescope (LAT) on board Fermi Gamma-ray Space (Fermi) used 10 months sky-survey...
The gamma-ray sky >100 MeV is dominated by the diffuse emissions from interactions of cosmic rays with interstellar gas and radiation fields Milky Way. Observations these provide a tool to study cosmic-ray origin propagation, medium. We present measurements first 21 months Fermi-LAT mission compare models emission generated using GALPROP code. are fitted data incorporate astrophysical input for distribution sources, fields. To assess uncertainties associated input, grid created varying...
A new study of the diffuse Galactic gamma-ray continuum radiation is presented, using a cosmic-ray propagation model which includes nucleons, antiprotons, electrons, positrons, and synchrotron radiation. Our treatment inverse Compton (IC) scattering effect anisotropic in interstellar field (ISRF) evaluation ISRF itself. Models based on locally measured electron nucleon spectra constraints are consistent with measurements 30-500 MeV range, but outside this range excesses apparent. harder...
We measured separate cosmic-ray electron and positron spectra with the Fermi Large Area Telescope. Because instrument does not have an onboard magnet, we distinguish two species by exploiting Earth's shadow, which is offset in opposite directions for charges due to magnetic field. estimate subtract proton background using different methods that produce consistent results. report electron-only spectrum, positron-only fraction between 20 GeV 200 GeV. confirm rises energy 20-100 range. The...
We have made a new calculation of the cosmic-ray secondary positron spectrum using diffusive halo model for Galactic propagation. The code computes self-consistently spectra primary and nucleons, electrons, positrons electrons. models are first adjusted to agree with observed Boron/Carbon ratio, interstellar proton Helium then computed; these used obtain source function positrons/electrons which finally propagated same parameters. electron is evaluated, again model. Fragmentation energy...
The third catalog of active galactic nuclei (AGNs) detected by the Fermi-LAT (3LAC) is presented. It based on (3FGL) sources between 100 MeV and 300 GeV with a Test Statistic (TS) greater than 25, 2008 August 4 2012 July 31. 3LAC includes 1591 AGNs located at high Galactic latitudes (|b|>10{\deg}), 71% increase over second 2 years data. There are 28 duplicate associations, thus 1563 2192 high-latitude gamma-ray 3FGL AGNs. Most them (98%) blazars. About half newly blazars unknown type, i.e.,...
Satellite galaxies of the Milky Way are among most promising targets for dark matter searches in gamma rays. We present a search consisting weakly interacting massive particles, applying joint likelihood analysis to 10 satellite with 24 months data Fermi Large Area Telescope. No signal is detected. Including uncertainty distribution, robust upper limits placed on annihilation cross sections. The 95% confidence level range from about 10(-26) cm3 s(-1) at 5 GeV 5×10(-23) 1 TeV, depending final...
We present a study of the compatibility some current models diffuse Galactic continuum γ-rays with EGRET data. A set regions sampling whole sky is chosen to provide comprehensive range tests. The data used extended 100 GeV. are computed our GALPROP cosmic-ray propagation and γ-ray production code. confirm that "conventional model" based on locally observed electron nucleon spectra inadequate, for all regions. conventional model plus hard sources in inner Galaxy also since this cannot explain...
The dwarf spheroidal satellite galaxies of the Milky Way are some most dark-matter-dominated objects known. Due to their proximity, high dark matter content, and lack astrophysical backgrounds, widely considered be among promising targets for indirect detection via $\ensuremath{\gamma}$ rays. Here we report on $\ensuremath{\gamma}$-ray observations 25 based 4 years Fermi Large Area Telescope (LAT) data. None significantly detected in rays, present flux upper limits between 500 MeV GeV. We...
High-energy collisions of cosmic-ray nuclei with interstellar gas are believed to be the mechanism producing majority antiprotons. Because kinematics process, they created a nonzero momentum; characteristic spectral shape maximum at ~2 GeV and sharp decrease toward lower energies makes antiprotons unique probe models for particle propagation in Galaxy modulation heliosphere. On other hand, accurate calculation secondary antiproton flux provides "background" searches exotic signals from...
Since 2012 August
The Fermi Large Area Telescope (LAT) has provided the most detailed view to date of emission towards Galactic centre (GC) in high-energy gamma-rays. This paper describes analysis data taken during first 62 months mission energy range 1-100 GeV from a $15^\circ \times 15^\circ$ region about direction GC, and implications for interstellar emissions produced by cosmic ray (CR) particles interacting with gas radiation fields inner Galaxy point sources detected. Specialised models (IEMs) are...
We present an incremental version (4FGL-DR3, for Data Release 3) of the fourth Fermi-LAT catalog gamma-ray sources. Based on first twelve years science data in energy range from 50 MeV to 1 TeV, it contains 6658 The analysis improves that used 4FGL over eight data: more sources are fit with curved spectra, we introduce a robust spectral parameterization pulsars, and extend points TeV. parameters, distributions, associations updated all Light curves rebuilt yr intervals (not 2 month...
Recent detections of the starburst galaxies M82 and NGC 253 by gamma-ray telescopes suggest that rapidly forming massive stars are more luminous at energies compared to their quiescent relatives. Building upon those results, we examine a sample 69 dwarf, spiral, ultraluminous infrared photon 0.1–100 GeV using 3 years data collected Large Area Telescope (LAT) on Fermi Gamma-ray Space (Fermi). Measured fluxes from significantly detected sources flux upper limits for remaining used explore...
We present a catalog of sources detected above 10 GeV by the Fermi Large Area Telescope (LAT) in first 7 years data using Pass 8 event-level analysis. This is Third Catalog Hard Fermi-LAT Sources (3FHL), containing 1556 objects characterized - 2 TeV energy range. The sensitivity and angular resolution are improved factors 3 relative to previous LAT at same energies (1FHL). vast majority (79%) associated with extragalactic counterparts other wavelengths, including 16 located very high...
The Fermi bubbles are two large structures in the gamma-ray sky extending to 55° above and below Galactic center. We analyze 50 months of Large Area Telescope data between 100 MeV 500 GeV 10° latitude derive spectrum morphology bubbles. thoroughly explore systematic uncertainties that arise when modeling diffuse emission through separate approaches. is well described by either a log parabola or power law with an exponential cutoff. exclude simple more than 7σ significance. cutoff has index...
The fourth catalog of active galactic nuclei (AGNs) detected by the Fermi Gamma-ray Space Telescope Large Area (4LAC) between 2008 August 4 and 2016 2 contains 2863 objects located at high Galactic latitudes (|b|>10{\deg}). It includes 85% more sources than previous 3LAC based on years data. AGNs represent least 79% high-latitude in Fermi-Large Source Catalog (4FGL), which covers energy range from 50 MeV to 1 TeV. In addition, 344 gamma-ray are found low latitudes. Most 4LAC blazars (98%),...
We report the discovery with Fermi/LAT of gamma-ray emission from three radio-loud narrow-line Seyfert 1 galaxies: PKS 1502+036 (z=0.409), 1H 0323+342 (z=0.061) and 2004-447 (z=0.24). In addition to PMN J0948+0022 (z=0.585), first source this type be detected in gamma rays, they may form an emerging new class active galactic nuclei (AGN). These findings can have strong implications on our knowledge about relativistic jets unified model AGN.
The origin of Galactic cosmic rays is a century-long puzzle. Indirect evidence points to their acceleration by supernova shockwaves, but we know little escape from the shock and evolution through turbulent medium surrounding massive stars. Gamma can probe spreading ambient gas radiation fields. Fermi Large Area Telescope (LAT) has observed star-forming region Cygnus X. 1- 100-gigaelectronvolt images reveal 50-parsec-wide cocoon freshly accelerated that flood cavities carved stellar winds...
The light emitted by stars and accreting compact objects through the history of Universe is encoded in intensity extragalactic background (EBL). Knowledge EBL important to understand nature star formation galaxy evolution, but direct measurements are lim- ited Galactic other foreground emissions. Here we report an absorption feature seen combined spectra a sample gamma-ray blazars out redshift z$\sim$1.6. This caused attenuation gamma rays at optical UV frequencies, allowed us measure flux...
The first $\ensuremath{\gamma}$-ray line originating from outside the Solar System that was ever detected is 511 keV emission positron annihilation in Galaxy. Despite 30 years of intense theoretical and observational investigation, main sources positrons have not been identified up to now. Observations 1990s with OSSE/CGRO (Oriented Scintillation Spectrometer Experiment on GRO satellite/Compton Gamma Ray Observatory) showed strongly concentrated toward Galactic bulge. In 2000s, spectrometer...
Dark matter particle annihilation or decay can produce monochromatic gamma-ray lines and contribute to the diffuse background. Flux upper limits are presented for spectral from 7 200 GeV background 4.8 264 obtained two years of Fermi Large Area Telescope data integrated over most sky. We give cross-section lifetime lower dark models that spectrum, including proposed as explanations PAMELA cosmic-ray data.