English
Related papers

Related papers: Vertical position of the Sun with $\gamma$-rays

200 papers

We study the high latitude (|b|>10) diffuse gamma-ray emission in the Galaxy in light of the recently published data from the Fermi collaboration at energies between 100 MeV and 100 GeV. The unprecedented accuracy in these measurements…

High Energy Astrophysical Phenomena · Physics 2013-04-16 I. Cholis , M. Tavakoli , C. Evoli , L. Maccione , P. Ullio

Gamma-ray line observations provide a versatile tool for studies of nucleosynthesis processes and supernova physics. In particular, the observation of radioactive species in the interstellar medium probes recent nucleosynthesis activity on…

Astrophysics · Physics 2007-05-23 Jurgen Knodlseder

The Sun emits copious amounts of photons and neutrinos in an approximately spatially isotropic distribution. Diffuse $\gamma$-rays and ultra-high energy (UHE) neutrinos from extragalactic sources may subsequently interact and annihilate…

High Energy Astrophysical Phenomena · Physics 2024-07-22 Shyam Balaji

We present a simple method for fitting parametrized mass models of the Milky Way to observational constraints. We take a Bayesian approach which allows us to take into account input from photometric and kinematic data, and expectations from…

Astrophysics of Galaxies · Physics 2015-05-27 Paul J. McMillan

(Abridged) We study the polarisation properties, magnetic field strength, and synchrotron emission scale-height of Milky-Way-like galaxies in comparison with other spiral galaxies. We use our 3D-emission model of the Milky Way Galaxy for…

Astrophysics of Galaxies · Physics 2015-06-05 X. H. Sun , W. Reich

We study the three-dimensional structure of the Milky Way using 65,981 Mira variable stars discovered by the Optical Gravitational Lensing Experiment (OGLE) survey. The spatial distribution of the Mira stars is analyzed with a model…

Precise starlight positions near the sun were measured during the 21 August 2017 total solar eclipse in order to measure their gravitational deflections. The equipment, procedures, and analysis are described in detail. A portable refractor,…

Instrumentation and Methods for Astrophysics · Physics 2018-03-28 Donald G. Bruns

We present accurate measurements of the central wavelengths of 4947 atomic absorption lines in the solar optical spectrum. The wavelengths, precise to a level ~ 50-150 m/s, are given for both flux and disc-centre spectra, as measured in…

Astrophysics · Physics 2009-10-30 Carlos Allende Prieto , Ramon J. Garcia Lopez

We calculate the intergalactic photon density as a function of both energy and redshift for 0 < z < 6 for photon energies from .003 eV to the Lyman limit cutoff at 13.6 eV in a Lambda-CDM universe with $\Omega_{\Lambda} = 0.7$ and…

Astrophysics · Physics 2010-11-11 F. W. Stecker , M. A. Malkan , S. T. Scully

We derive the value of the dark matter density at the Sun's location (rho_0) without globally mass-modeling the Galaxy. The proposed method relies on the local equation of centrifugal equilibrium and is independent of i) the shape of the…

Astrophysics of Galaxies · Physics 2015-05-18 P. Salucci , F. Nesti , G. Gentile , C. Frigerio Martins

The solar disk is among the brightest gamma-ray sources in the sky. It is also among the most mysterious. No existing model fully explains the luminosity, spectrum, time variability, and morphology of its emission. We perform the first…

High Energy Astrophysical Phenomena · Physics 2020-12-15 Tim Linden , John F. Beacom , Annika H. G. Peter , Benjamin J. Buckman , Bei Zhou , Guanying Zhu

The light distribution in the inner few kiloparsecs of the Milky Way is recovered non-parametrically from a dust-corrected near-infrared COBE/DIRBE surface brightness map of the inner Galaxy. The best fits to the photometry are obtained…

Astrophysics · Physics 2015-06-24 James Binney , Ortwin Gerhard , David Spergel

We use the kinematics of $\sim200\,000$ giant stars that lie within $\sim 1.5$ kpc of the plane to measure the vertical profile of mass density near the Sun. We find that the dark mass contained within the isodensity surface of the dark…

The center of the Milky Way is a prime site to search for signals of dark matter (DM) annihilation due to its proximity and expected high concentration of DM. The amplification of the dispersion velocity of DM particles in the Galactic…

High Energy Astrophysical Phenomena · Physics 2023-10-25 Alessandro Montanari , Oscar Macias , Emmanuel Moulin

We study the gamma rays observed by the Fermi Gamma Ray Space Telescope from the direction of the Galactic Center and find that their angular distribution and energy spectrum are well described by a dark matter annihilation scenario. In…

High Energy Physics - Phenomenology · Physics 2009-11-11 Lisa Goodenough , Dan Hooper

ALMA observations of the Sun at mm-$\lambda$ offer a unique opportunity to investigate the temperature structure of the solar chromosphere. In this article we expand our previous work on modeling the chromospheric temperature of the quiet…

Solar and Stellar Astrophysics · Physics 2020-08-19 C. E. Alissandrakis , A. Nindos , T. S. Bastian , S. Patsourakos

We have used the Very Long Baseline Array (VLBA) at 43, 23 and 15 GHz to measure the solar gravitational deflection of radio waves among four radio sources during an 18-day period in October 2005. Using phase-referenced radio interferometry…

Cosmology and Nongalactic Astrophysics · Physics 2009-07-22 E. Fomalont , S. Kopeikin , G. Lanyi , J. Benson

Various theoretical models predict the existence of extended $\gamma$-ray halo around normal galaxies that could be produced by interactions of cosmic rays with the circumgalactic medium or by annihilation or decay of hypothetical dark…

High Energy Astrophysical Phenomena · Physics 2026-04-03 M. S. Pshirkov , B. A. Nizamov

Using N-body simulations of the Milky Way interacting with a satellite similar to the Sagittarius dwarf galaxy, we quantitatively analyse the vertical response of the Galactic disc to the satellite's repeated impacts. We approximate the…

We analyze 15 years of Fermi-LAT data and produce a detailed model of the Sun's inverse-Compton scattering emission (solar halo), which is powered by interactions between ambient cosmic-ray electrons and positrons with sunlight. By…

High Energy Astrophysical Phenomena · Physics 2026-01-28 Tim Linden , Jung-Tsung Li , Bei Zhou , Isabelle John , Milena Crnogorčević , Annika H. G. Peter , John F. Beacom
‹ Prev 1 3 4 5 6 7 10 Next ›