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We model the transport of cosmic ray nuclei in the Galaxy by means of a new numerical code. Differently from previous numerical models we account for a generic spatial distribution of the diffusion coefficient. We found that in the case of…

天体物理学 · 物理学 2016-05-19 C. Evoli , D. Gaggero , D. Grasso , L. Maccione

The $l=-1.2^{\circ}$ region in the Galactic center has a high CO $J$=3-2/$J$=1-0 intensity ratio and extremely broad velocity width. This paper reports the detection of five expanding shells in the $l=-1.2^{\circ}$ region based on the CO…

Context: Mass-loss occurring in red supergiants (RSGs) is a major contributor to the enrichment of the interstellar medium in dust and molecules. The physical mechanism of this mass loss is however relatively poorly known. Betelgeuse is the…

太阳与恒星天体物理 · 物理学 2011-06-27 Pierre Kervella , Guy Perrin , Andrea Chiavassa , Stephen T. Ridgway , Jan Cami , Xavier Haubois , Tijl Verhoelst

The flux of unstable secondary cosmic ray nuclei, produced by spallation processes in the interstellar medium, can be used to constrain the residence time of cosmic rays inside the Galaxy. Among them, $^{10}$Be is especially useful because…

高能天体物理现象 · 物理学 2020-01-29 Carmelo Evoli , Giovanni Morlino , Pasquale Blasi , Roberto Aloisio

Bubble nuclei are characterized by a depletion of their central density. Their existence is examined within three different theoretical frameworks: the shell model as well as non-relativistic and relativistic microscopic mean-field…

Over the past decade, studies of dust in the Andromeda galaxy (M31) have shown radial variations in the dust emissivity index ($\beta$). Understanding the astrophysical reasons behind these radial variations may give clues about the…

星系天体物理 · 物理学 2021-11-17 G. Athikkat-Eknath , S. A. Eales , M. W. L. Smith , A. Schruba , K. A. Marsh , A. P. Whitworth

The discovery of radionuclides like 60Fe with half-lives of million years in deep-sea crusts and sediments offers the unique possibility to date and locate nearby supernovae. We want to quantitatively establish that the 60Fe enhancement is…

高能天体物理现象 · 物理学 2017-08-16 Michael Mathias Schulreich , Dieter Breitschwerdt , Jenny Feige , Christian Dettbarn

The Local and Loop I superbubbles are the closest and best investigated supernova (SN) generated bubbles and serve as test laboratories for observations and theories of the interstellar medium. Since the morphology and dynamical evolution…

天体物理学 · 物理学 2009-11-11 Dieter Breitschwerdt , Miguel A. de Avillez

The model of a Local Hot Bubble has been widely accepted as providing a framework that can explain the ubiquitous presence of the soft X-ray background diffuse emission. We summarize the current knowledge on this local interstellar region,…

星系天体物理 · 物理学 2009-08-11 Barry Y. Welsh , Robin L. Shelton

We present FUSE observations of the interstellar gas toward 30 white dwarf and 1 subdwarf (SdO) stars. These sightlines probe the Local Bubble (LB) and the local interstellar medium (LISM) near the LB. Our survey detected only diffuse H_2…

天体物理学 · 物理学 2008-11-26 N. Lehner , E. B. Jenkins , C. Gry , H. W. Moos , P. Chayer , S. Lacour

We report two simulations that have been carried out at the SX-5 at HLRS (Stuttgart). One simulation is axisymmetric and purely hydrodynamic, but with a resolution of 20 points per beam-radius (ppb). The bipolar jet is injected in the…

天体物理学 · 物理学 2007-05-23 Martin G. H. Krause , Max Camenzind

We report the radio observations of a sub-sample of the 428 galactic compact bubbles discovered at 24 $\mu$m with the MIPSGAL survey. Pervasive through the entire Galactic plane, these objects are thought to be different kinds of evolved…

30 Doradus C is a superbubble which emits the brightest nonthermal X- and TeV gamma-rays in the Local Group. In order to explore detailed connection between the high energy radiation and the interstellar medium, we have carried out new CO…

In this paper we report a study of the isotopic composition of Li, Be, B and N, Ne nuclei from a 5 year time period beyond the heliopause using the CRS instruments on Voyager. By comparing the isotopic ratios, 15N/14N and 22Ne/20Ne outside…

空间物理 · 物理学 2018-10-22 W. R. Webber , N. Lal , B. Heikkila

We present an analysis of the X-ray spectrum of the Local Bubble, obtained by simultaneously analyzing spectra from two XMM-Newton pointings on and off an absorbing filament in the Southern galactic hemisphere (b ~ -45 deg). We use the…

天体物理学 · 物理学 2014-10-13 David B. Henley , Robin L. Shelton , K. D. Kuntz

Recent measurements of the cosmic ray (CR) antiproton flux have been shown to challenge existing CR propagation models. It was shown that the reacceleration models designed to match secondary to primary nuclei ratios (e.g., B/C) produce too…

天体物理学 · 物理学 2010-05-27 I. V. Moskalenko , A. W. Strong , J. F. Ormes , S. G. Mashnik

We present photometry in U, B, V, R and I continuum bands and in H$\alpha$ and H$\beta$ emission lines for a sample of 336 circumnuclear star forming regions (CNSFR) located in early type spiral galaxies with different levels of activity in…

星系天体物理 · 物理学 2017-01-04 Mar Álvarez-Álvarez , Angeles I. Díaz , Elena Terlevich , Roberto Terlevich

Recently, a few-degrees extended $\gamma$-ray halo in the direction of Geminga pulsar has been detected by HAWC, Milagro and Fermi-LAT. These observations can be interpreted with positrons ($e^+$) and electrons ($e^-$) accelerated by…

高能天体物理现象 · 物理学 2021-12-07 Mattia Di Mauro , Silvia Manconi , Fiorenza Donato

The Fermi Gamma-ray Space Telescope reveals two large bubbles in the Galaxy, which extend nearly symmetrically ~50 degrees above and below the Galactic center (GC). Using three-dimensional (3D) magnetohydrodynamic (MHD) simulations that…

星系天体物理 · 物理学 2015-06-05 H. -Y. K. Yang , M. Ruszkowski , P. M. Ricker , E. Zweibel , D. Lee

The observation of 21 X-ray dust-scattering rings around the extraordinarily bright gamma-ray burst (GRB) 221009A provides a unique opportunity to study the interstellar medium (ISM) through which the X-ray radiation traveled in our Galaxy…

高能天体物理现象 · 物理学 2025-04-02 B. Vaia , Ž. Bošnjak , A. Bracco , S. Campana , P. Esposito , V. Jelić , A. Sacchi , A. Tiengo