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Related papers: Pulsars as the Source of the WMAP Haze

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Pulsars are neutron stars, stellar corpses left over after supernova explosions of stars about ten times as massive as our Sun, with densities comparable to the atomic nucleus', spinning with periods from few milliseconds up to few seconds,…

Some of the most energetic pulsars exhibit rotation-modulated gamma-ray emission in the $0.1$ to $100$ GeV band. The luminosity of this emission is typically $0.1\text{-}10\%$ of the pulsar spin-down power (gamma-ray efficiency), implying…

High Energy Astrophysical Phenomena · Physics 2023-03-20 Hayk Hakobyan , Alexander Philippov , Anatoly Spitkovsky

Pulsars are known to emit non-thermal radio emission that is generally a power-law function of frequency. In some cases, a turnover is seen at frequencies around 100~MHz. Kijak et al. have reported the presence of a new class of ''Gigahertz…

High Energy Astrophysical Phenomena · Physics 2015-11-11 Kaustubh Rajwade , Duncan R Lorimer , Loren D Anderson

Annihilation of Dark Matter usually produces together with gamma rays comparable amounts of electrons and positrons. The e+e- gyrating in the galactic magnetic field then produce secondary synchrotron radiation which thus provides an…

Astrophysics · Physics 2009-08-19 Enrico Borriello , Alessandro Cuoco , Gennaro Miele

Observations of the INTEGRAL satellite revealed the presence of yet unexplained excess in the central region of the Galaxy at the energies around 511 keV. These gamma-rays are produced in the process of positron annihilation, the needed…

High Energy Astrophysical Phenomena · Physics 2016-11-15 Maxim S. Pshirkov

We present the results of our radio interferometric observations of pulsars at 325 MHz and 610 MHz using the Giant Metrewave Radio Telescope (GMRT). We used the imaging method to estimate the flux densities of several pulsars at these radio…

High Energy Astrophysical Phenomena · Physics 2017-05-24 J. Kijak , R. Basu , W. Lewandowski , K. Rozko , M. Dembska

We constrain the spectral index of polarized synchrotron emission, $\beta_s$, by correlating the recently released 2.3 GHz S-Band Polarization All Sky Survey (S-PASS) data with the 23 GHz 9-year Wilkinson Microwave Anisotropy Probe (WMAP)…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-12 U. Fuskeland , K. J. Andersen , R. Aurlien , R. Banerji , M. Brilenkov , H. K. Eriksen , M. Galloway , E. Gjerløw , S. K. Næss , T. L. Svalheim , I. K. Wehus

We review the present knowledge of the diffuse Galactic synchrotron emission in polarisation. At microwave frequencies, we assess the expected contamination to the CMB polarisation angular power spectrum, for $E$ and $B$ modes, as expected…

Astrophysics · Physics 2015-06-24 Carlo Baccigalupi

The H.E.S.S. telescope has recently detected the total electron-plus-positron ($e^+e^-$) flux up to 40 TeV, finding it to be a featureless and steeply-falling power-law above 1 TeV. This result is in stark tension with standard one-zone…

High Energy Astrophysical Phenomena · Physics 2025-03-25 Isabelle John , Tim Linden

The high-frequency radio sky is bursting with synchrotron transients from massive stellar explosions and accretion events, but the low-frequency radio sky has so far been quiet beyond the Galactic pulsar population and the long-term…

High Energy Astrophysical Phenomena · Physics 2025-03-12 N. Hurley-Walker , X. Zhang , A. Bahramian , S. J. McSweeney , T. N. O'Doherty , P. J. Hancock , J. S. Morgan , G. E. Anderson , G. H. Heald , T. J. Galvin

Very high-energy gamma-rays (VHE; E>100 GeV) have been detected from the direction of the Galactic Centre up to energies E>10 TeV. Up to now, the origin of this emission is unknown due to the limited positional accuracy of the observing…

Astrophysics of Galaxies · Physics 2010-02-12 A. Abramowski , S. Gillessen , D. Horns , H. -S. Zechlin

The cosmic-ray positron flux calculated using the cosmic-ray nuclei interactions in our Galaxy cannot explain observed data above 10 GeV. An excess in the measured positron flux is therefore open to interpretation. Nearby pulsars, located…

High Energy Astrophysical Phenomena · Physics 2017-10-04 Jagdish C. Joshi , Soebur Razzaque

Here we investigate to what extent unresolved \gr pulsars contribute to the galactic diffuse emission, and further whether unresolved \gr pulsars can be made responsible for the excess of diffuse galactic emission above 1 GeV which has been…

Astrophysics · Physics 2009-10-30 Martin Pohl

The Compton Gamma Ray Observatory revealed the high energy emission of some Active Galactic Nuclei called "Blazars"; few of them have also been observed by ground Cererenkov arrays. Those sources observed with Whipple Observatory emit gamma…

Astrophysics · Physics 2007-05-23 G. Pelletier , G. Henri

Electron and positron fluxes in cosmic rays are currently measured with unprecedented precision by AMS-02 up to TeV energies, and represent unique probes for the local properties of our Galaxy. The interpretation of their spectra is at…

High Energy Astrophysical Phenomena · Physics 2022-09-13 Silvia Manconi

Galactic foreground emission is a limiting factor for precise cosmic microwave background (CMB) anisotropy measurements. We perform an angular power spectrum analysis (APS) of all-sky total intensity maps at 408 MHz and 1420 MHz, which are…

Astrophysics · Physics 2009-11-13 L. La Porta , C. Burigana , W. Reich , P. Reich

Millisecond pulsars have been discussed as a possible source of the gamma-ray excess observed from the region surrounding the Galactic Center. With this in mind, we use the observed population of bright low-mass X-ray binaries to estimate…

High Energy Astrophysical Phenomena · Physics 2016-03-01 Ilias Cholis , Dan Hooper , Tim Linden

The turbulent ionized interstellar medium diffracts radio waves and makes them propagate in multiple paths. The pulse-broadening observed at low frequencies results from the scattering effect of interstellar clouds of ionized gas. During…

High Energy Astrophysical Phenomena · Physics 2025-06-18 W. C. Jing , J. L. Han , C. Wang , P. F. Wang , T. Wang , N. N. Cai , J. Xu , Z. L. Yang , D. J. Zhou , Yi Yan , W. Q. Su , X. Y. Gao , L. Xie

The WMAP team has produced a foreground map that can account for most of the low-frequency Galactic microwave emission in the WMAP maps, tentatively interpreting it as synchrotron emission. Finkbeiner and collaborators have challenged these…

One fundamental question about pulsars concerns the mechanism of their pulsed electromagnetic emission. Measuring the high-end region of a pulsar's spectrum would shed light on this question. By developing a new electronic trigger, we…

Astrophysics · Physics 2009-04-08 The MAGIC Collaboration , E. Aliu