Results 21 to 30 of about 19,051 (197)

A tool to understand emission mechanisms of blazars through their high‐energy gamma‐ray emission

Astronomische Nachrichten, Volume 344, Issue 6, August 2023., 2023
The blazar SED is characterized by two energy components. Evidence suggests that the low‐energy component is generated by the synchrotron mechanism, but for the high‐energy component, the mechanism is still uncertain. Two main models have been proposed to explain this emission. According to the leptonic model, a correlation between the emission of both
Mabel Osorio, Erick Rangel, José Rodrigo Sacahui, María Magdalena González   +3 more
wiley   +1 more source

Multiwavelength astrophysics of the blazar OJ 287 and the project MOMO

Astronomische Nachrichten, Volume 344, Issue 4, May 2023., 2023
Abstract We are carrying out the densest and longest multiyear, multiwavelength monitoring project of OJ 287 ever done. The project MOMO (Multiwavelength Observations and Modeling of OJ 287) covers wavelengths from the radio to the high‐energy regime. A few selected observations are simultaneous with those of the Event Horizon Telescope (EHT).
S. Komossa, A. Kraus, D. Grupe, M.L. Parker, A. Gonzalez, L.C. Gallo, M.A. Gurwell, S. Laine, S. Yao, S. Chandra, L. Dey, J.L. Gómez, K. Hada, D. Haggard, A.R. Hollett, H. Jermak, S. Jorstad, T.P. Krichbaum, S. Markoff, C. McCall, J. Neilsen, M. Nowak   +21 more
wiley   +1 more source

A new multi‐messenger description of starburst galaxies emission: perspectives for neutrino and gamma‐ray observations

Astronomische Nachrichten, Volume 344, Issue 1-2, January-February 2023., 2023
Abstract Star‐forming and starburst galaxies (SBGs), which are well‐known cosmic‐ray (CR) reservoirs, are expected to emit gamma rays and neutrinos predominantly via hadronic collisions. In this work we analyze the 10‐year Fermi‐Low Energy Technique (LAT) spectral energy distributions of 13 nearby galaxies by means of a physical model that accounts for
Antonio Marinelli, Antonio Ambrosone, Marco Chianese, Damiano Fiorillo, Gennaro Miele, Ofelia Pisanti   +5 more
wiley   +1 more source

Milestones in the Observations of Cosmic Magnetic Fields [PDF]

, 2002
Magnetic fields are observed everywhere in the universe. In this review, we concentrate on the observational aspects of the magnetic fields of Galactic and extragalactic objects.
Alfven H., Anantharamaiah K. R., Andreasyan R. R., Appenzeller I., Argon A. L., Athreya R. M., Axon D. J., Baker J. R., Baker J. R., Baryshnikova I., Battaner E., Beck R., Behr A., Bel N., Berdyugin A., Berdyugin A., Berkhuijsen E. M., Berkhuijsen E. M., Berkhuijsen E. M., Beuermann K., Bhatt H. C., Bicknell G. V., Biermann L., Bingham R. G., Birk G. T., Blackman E. G., Blackman E. G., Blackman E. G., Blasi P., Bourke T. L., Bower G. C., Brandenburg A., Brandenburg A., Brandenburg A., Bridle A. H., Brouw W. N., Brown J. C., Brunthaler A., Carilli C. L., Caswell J. L., Chy_zy K. T., Cimatti A., Clarke T. E., Contopoulos I., Cooper B. F. C., Costa M. E., Crutcher R. M., Crutcher R. M., Crutcher R. M., Cudlip W., Dahlem M., de Araujo J. C. N., Deiss B. M., Dickey J. M., Dickey J. M., Dombrovsky V. A., Dowell C. D., Draper P. W., Dumke M., Duncan A. R., Duncan A. R., Duncan A. R., Eilek J. A., Elvius A., Elvius A., Elvius A., Fendt C., Fendt C., Feretti L., Ferriere K., Fiebig D., Fosalba P., Furlanetto S. R., Furst E., Furst E., Gaensler B. M., Gardner F. F., Gardner F. F., Gavazzi G., Gnedin N. Y., Golla G., Gomez de Castro A. I., Goodman A. A., Gray A. D., Greaves J. S., Greaves J. S., Hall J. S., Hamilton P. A., Han J. L., Han J. L., Han J. L., Han J. L., Han J. L., Hanisch R. J., Harris D. E., Harris D. E., Harrison E. R., Haslam C. G. T., Haslam C. G. T., Haslam C. G. T., Haverkorn M., Haynes R. F., Haynes R. F., Haynes R. F., Heiles C., Heiles C., Henriksen M., Hogbom J. A., Holland W. S., Homan D. C., Houde M., Howard A. M., Inoue M., Inoue M., Jin-Lin Han, Johnson R. A., Junkes N., Kempner J. C., King D. J., Kishimoto M., Klaas U., Klare G., Klein U., Klein U., Knapik J., Kolatt T., Korhonen T., Krause F., Krause F., Krause M., Krause M., Krause M., Krautter J., Kronberg P. P., Kronberg P. P., Kronberg P. P., Kulsrud R. M., Landecker T. L., Lang C. C., Lang C. C., LaRosa T. N., LaRosa T. N., Leroy J. L., Lesch H., Levin S. M., Li Z., Liang H., Loden L. O., Lyne A. G., Lähteenmäki A., Macquart J.-P., Manchester R. N., Markevitch M., Markkanen T., Mathewson D. S., Mathewson D. S., Mathewson D. S., Mathewson D. S., McClure-Griffiths N. M., Mestel L., Mitra D., Momose M., Morris M., Moss D., Neininger N., Neininger N., Novak G., Novak G., Novak G., Onaka T., Oort J. H., Parker E. N., Pawsey J. L., Piddington J. H., Pierce-Price D., Qiao G. J., Rand R. J., Rao R., Razin V. A., Rees M. J., Reich W., Reich W., Reich W., Reich W., Reich W., Reuter H.-P., Richard Wielebinski, Rohde R., Ruzmaikin A. A., Ruzmaikin A. A., Ryle M., Sarma A. P., Sarma A. P., Scarrott S. M., Scarrott S. M., Scarrott S. M., Scarrott S. M., Scarrott S. M., Scarrott S. M., Schekochihin A. A., Schleuning D. A., Schlickeiser R., Schmidt T., Schroder R., Serkowski K., Shklovsky I. S., Sicotte H., Sofue Y., Sofue Y., Sofue Y., Spoelstra T. A. T., Spoelstra T. A. T., Spoelstra T. A. T., Spoelstra T. A. T., Spoelstra T. A. T., Steenbeck M., Steenbeck M., Stix M., Subramanian K., Subramanian K., Tabara H., Tadhunter C. N., Tamura M., Taylor G. B., Thomson R. C., Thum C., Tosa M., Totani T., Udomprasert P. S., Vallee J. P., Vallee J. P., Vallee J. P., van Ommen, Venturi T., Walmsley M., Ward-Thompson D., Westerhout G., Wiechen H., Wielebinski R., Wielebinski R., Wielebinski R., Wielebinski R., Wieringa M. H., Wilkinson A., Willson M. A. G., Woltjer L., Wood K., Yusef-Zadeh F., Yusef-Zadeh F., Zeldovich I. B., Zheng X.   +250 more
core   +2 more sources

LRS Bianchi Type‐I String Cosmological Models in f(Q) Gravity

Journal of Mathematics, Volume 2023, Issue 1, 2023., 2023
In the current study, we studied a f(Q)‐gravitational, anisotropic, locally rotationally symmetric (LRS), Bianchi type‐I spacetime universe. We have adopted the freely chosen function fQ=Q+αQ, where α is a model‐free parameter. We assumed that the universe is filled with dusty string fluid and that the shear scalar (σ) and the expansion scalar (θ) are ...
Mukesh Kumar, Manvinder Singh, Mohit Bajaj, Hossam Kotb, Djeudjo Temene Hermann, Bibhas Ranjan Majhi   +5 more
wiley   +1 more source

A Wideband Polarization Observation of Hydra A with the Jansky Very Large Array

The Astrophysical Journal, 2023
We present the results of a wideband high-resolution polarization study of Hydra A, one of the most luminous FR I radio galaxies known and among the most well studied. The radio emission from this source displays extremely large Faraday rotation measures
Lerato Baidoo, Richard A. Perley, Jean Eilek, Oleg Smirnov, Valentina Vacca, Torsten Enßlin   +5 more
doaj   +1 more source

Soft X‐Ray Imaging of Magnetopause Reconnection Outflows Under Low Plasma‐β Solar Wind Conditions

Geophysical Research Letters, Volume 49, Issue 19, 16 October 2022., 2022
Abstract We examined soft X‐ray emission by the solar wind charge‐exchange process around the Earth's magnetosphere using a global magnetohydrodynamic simulation model. The dayside magnetopause reconnection heats and accelerates the plasma whereby the X‐ray emission becomes as bright as ∼6 × 10−6 eV cm−3 s−1 under the southward interplanetary magnetic ...
Yosuke Matsumoto, Yoshizumi Miyoshi
wiley   +1 more source

Investigating Effects of Solar Proton Events and Forbush Decreases on Ground‐Level Potential Gradient Recorded at Middle and Low Latitudes and Different Altitudes

Space Weather, Volume 20, Issue 3, March 2022., 2022
Abstract High‐energetic charged particles, such as solar protons, and phenomena such as Forbush decreases are eligible candidates to affect the global electric circuit. These effects have been studied by analyzing disturbances of the potential gradient in ground‐based measurements in fair weather regions. In this paper, we investigate deviations in the
J. Tacza, A. Odzimek, E. Tueros Cuadros, J.‐P. Raulin, M. Kubicki, G. Fernandez, A. Marun   +6 more
wiley   +1 more source

Generation of 10^15 - 10^17 eV photons by UHE CR in the Galactic magnetic filed [PDF]

, 1999
We show that the deep expected in the diffuse photon spectrum above the threshold of e+e- pair production, i.e., at energies 10^15 - 10^17 eV, may be absent due to the synchrotron radiation by the electron component of the extragalactic Ultra-High Energy
A. V. Glushkov, D. Ryu, K. Greisen, L. D. Landau, M. Aglietta, M. C. Chantel, M. Takeda, P. G. Tinyakov, P. P. Kronberg, R. J. Could, S. I. Nikolsky, S. L. Dubovsky, S. L. Dubovsky, T. Stanev, V. A. Kuzmin   +14 more
core   +4 more sources

Modeling Particle Transport in Astrophysical Outflows and Simulations of Associated Emissions from Hadronic Microquasar Jets

Advances in High Energy Physics, Volume 2022, Issue 1, 2022., 2022
In this work, after improving the formulation of the model on particle transport within astrophysical plasma outflows and constructing the appropriate algorithms, we test the reliability and effectiveness of our method through numerical simulations on well‐studied galactic microquasars as the SS 433 and the Cyg X‐1 systems.
D. A. Papadopoulos, O. T. Kosmas, S. Ganatsios, Mariana Frank   +3 more
wiley   +1 more source