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Related papers: Modelling the 1.8 MeV Sky: Tests for Spiral Struct…

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We present maps of the 22MHz radio emission between declinations -28d and +80d, covering ~73% of the sky, derived from observations with the 22MHz radiotelescope at the Dominion Radio Astrophysical Observatory (DRAO). The resolution of the…

Astrophysics · Physics 2009-10-31 R. S. Roger , C. H. Costain , T. L. Landecker , C. M. Swerdlyk

An intergalactic magnetic field stronger than $3\times10^{-13}$~G would explain the lack of a bright, extended degree-scale, GeV-energy inverse Compton component in the gamma-ray spectra of TeV-blazars. A robustly predicted consequence of…

High Energy Astrophysical Phenomena · Physics 2018-12-05 Avery E. Broderick , Paul Tiede , Philip Chang , Astrid Lamberts , Christoph Pfrommer , Ewald Puchwein , Mohamad Shalaby , Maria Werhahn

We discuss a model for the Milky Way obtained by fitting the observed terminal velocities with the radial acceleration relation. The resulting stellar surface density profile departs from a smooth exponential disk, having bumps and wiggles…

Astrophysics of Galaxies · Physics 2019-11-06 Stacy McGaugh

We use ALMA observations of four sub-millimetre galaxies (SMGs) at $z\sim2-3$ to investigate the spatially resolved properties of the inter-stellar medium (ISM) at scales of 1--5 kpc (0.1--0.6$''$). The velocity fields of our sources,…

We use deep Hubble Space Telescope imaging to study stellar populations in the outer halo of the spiral galaxy M96, located in the dynamically active Leo I galaxy group. Our imaging targets two fields at a projected distance of 50 kpc from…

Astrophysics of Galaxies · Physics 2026-01-30 J. Christopher Mihos , Patrick R. Durrell , Brian Malkan , Aaron E. Watkins

IRAC images of M81 show three distinct morphological constituents: a smooth distribution of evolved stars with bulge, disk, and spiral arm components; a clumpy distribution of dust emission tracing the spiral arms; and a pointlike nuclear…

The nature of the soft gamma-ray (20-200 keV) Galactic emission has been a matter of debate for a long time. Previous experiments have tried to separate the point source contribution from the real interstellar emission, but with a rather…

Many galaxy clusters have giant halos of non-thermal radio emission, indicating the presence of relativistic electrons in the clusters. Relativistic protons may also be accelerated by merger and/or accretion shocks in galaxy clusters. These…

High Energy Astrophysical Phenomena · Physics 2018-09-19 Shao-Qiang Xi , Xiang-Yu Wang , Yun-Feng Liang , Fang-Kun Peng , Rui-Zhi Yang , Ruo-Yu Liu

We introduce a study of the massive star forming region IRAS 18144--1723 using observations of the 6.7 GHz methanol maser line. Such regions are opaque at short wavelengths but can be observed through radio emission lines. In this study we…

Solar and Stellar Astrophysics · Physics 2022-12-07 Esraa Khafagy , khaled A. Edris , Osama M. Shalabiea , Anna Bartkiewicz , Anita M. S. Richards , Zainab Awad

We perform spatial and spectral analyses of the Large Magellanic Cloud (LMC) gamma-ray emission collected over 66 months by the Fermi Gamma-ray Space Telescope. In our spatial analysis, we model the LMC cosmic-ray distribution and gamma-ray…

High Energy Astrophysical Phenomena · Physics 2015-08-06 Gary Foreman , You-Hua Chu , Robert Gruendl , Annie Hughes , Brian Fields , Paul Ricker

Gamma-ray lines from radioactive isotopes, ejected into interstellar space by cosmic nucleosynthesis events, are observed with new space telescopes. The Compton Observatory had provided a sky survey for the isotopes 56Co, 22Na, 44Ti, and…

Astrophysics · Physics 2009-11-10 Roland Diehl

Cosmic nucleosynthesis co-produces unstable isotopes, which emit characteristic gamma-ray emission lines upon their radioactive decay that can be measured with SPI on INTEGRAL. High spectral resolution allows to derive velocity constraints…

High Energy Astrophysical Phenomena · Physics 2012-02-03 Roland Diehl

The circumgalactic medium (CGM) of the Milky Way is composed of a tenuous atmosphere filled with multi-phase plasma, including a warm-hot virialised component. Recent studies suggest a much hotter (~0.7 keV) super-virial component detected…

We present a measurement of the sky distribution of positronium (Ps) annihilation continuum emission obtained with the SPI spectrometer on board ESA's INTEGRAL observatory. The only sky region from which significant Ps continuum emission is…

The COMPTEL experiment on CGRO observed the gamma-ray sky at energies from 0.75 MeV to 30 MeV between April 1991 and June 2000. COMPTEL detected many gamma-ray sources, among them an unidentified one labeled GRO J1823-12, which is…

High Energy Astrophysical Phenomena · Physics 2014-05-08 W. Collmar , S. Zhang

We study the exponential scale length of total radio emission, the spectral index distribution, and the linear radio polarization in the Scd galaxy M33. Observations were carried out using the 3.6 cm dual channel and the 6.2 cm four channel…

Astrophysics · Physics 2009-11-13 F. S. Tabatabaei , M. Krause , R. Beck

It is presumed that the observed cosmic rays up to about $3\times 10^{18}$ eV are of Galactic origin, the particles being the ones which are found in the composition of the stellar winds of stars that explode as supernova into the…

Astrophysics · Physics 2007-05-23 Adrian Sabin Popescu

The properties of spatial distribution of luminous matter are investigated analysing all the available three dimensional catalogues of galaxies. In standard view, galaxies are believed to have a fractal distribution at small scale with a…

Astrophysics · Physics 2016-08-30 M. Montuori , F. Sylos Labini , L. Pietronero

The spiral arm tangencies are ideal lines of sight in which to determine the distribution of interstellar gas components in the spiral arms and study the influence of spiral density waves on the interarm gas in the Milky Way. We present a…

Astrophysics of Galaxies · Physics 2015-04-15 T. Velusamy , W. D. Langer , P. F. Goldsmith , J. L. Pineda