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Related papers: Variations of paleointensity in the Paleogene

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We study changes in the $\gamma$-ray intensity at very high energies observed from selected active galactic nuclei. Publicly available data collected by Cherenkov telescopes were examined by means of a simple method utilizing solely the…

High Energy Astrophysical Phenomena · Physics 2014-12-15 Stanislav Stefanik , Dalibor Nosek

During solar flares, a considerable portion of the flare atmosphere becomes heated; however, the energy deposition process is still unclear, especially in the lower solar atmosphere. Here, we present spectroscopic and imaging observations…

Solar and Stellar Astrophysics · Physics 2026-03-24 Girjesh Gupta , Ananya Rawat , Helen Mason , Robertus Erdélyi

The emission in the hyperfine structure 21 cm line of atomic hydrogen arising in the halos with masses $\sim10^6-10^{10}$ M$_\odot$ from the Dark Ages in the models with Warm Dark Matter (WDM) is analysed. The halos are assumed to be formed…

Cosmology and Nongalactic Astrophysics · Physics 2020-02-25 B. Novosyadlyj , V. Shulga , Yu. Kulinich , W. Han

Paleo-Sciences including palaeoclimatology and palaeoecology have accumulated numerous records related to climatic changes. The researchers have usually tried to identify periodic and quasi-periodic processes in these paleoscientific…

We have examined images from the Precision Solar Photometric Telescope (PSPT) at the Mauna Loa Solar Observatory (MLSO) in search of latitudinal variation in the solar photospheric intensity. Along with the expected brightening of the solar…

Astrophysics · Physics 2009-11-13 Mark P. Rast , Ada Ortiz , Randle W. Meisner

We report an extensive study on the zero field ground state of a powder sample of the pyrochlore $\mathrm{Yb_2Ti_2O_7}$. A sharp heat capacity anomaly that labels a low temperature phase transition in this material is observed at 280 mK.…

During the centennial period from 1900 to 2000, the globally averaged unsigned annual rate of the main geomagnetic field experienced a three-episode variation. The maximum annual rates occurred respectively around 1910-1920, 1940-1950, and…

Geophysics · Physics 2022-09-15 Wen-Yao Xu , Henri-Claude Nataf , Zi-Gang Wei , Ai-Min Du

Magnetic properties of a polycrystalline alloy Ni$_{2.19}$Mn$_{0.81}$Ga, which undergoes a first-order magnetostructural phase transition from cubic paramagnetic to tetragonal ferromagnetic phase, are studied. Hysteretic behavior of…

A strong case has been made that radio waves from sources within about half a degree of the Galactic Center undergo extreme diffractive scattering. However, problems arise when standard (``Kolmogorov'') models of electron density…

Astrophysics · Physics 2009-11-11 Peter Goldreich , S. Sridhar

It had been observed by Linkov, Petrova and Osipov (1992) that there exist periodic 4-6 hours pulses of 200 microHz seismogravitational oscillations ( SGO ) before 95 % of powerful earthquakes. We explain this by beating between an…

Geophysics · Physics 2015-10-13 V. V. Flambaum , B. S. Pavlov

Chaotic, eddy-like motions dominated by inertial-vortex forces begin immediately at Planck scales in a hot big-bang cosmological model. This quantum-gravitational-dynamics epoch produced not only the first space-time-energy of the universe…

Astrophysics · Physics 2007-05-23 Carl H. Gibson

The magnetar 1E~1547$-$5408 recently exhibited two periods of outburst, beginning on 2008 October 3 and 2009 January 22. Here we present an analysis of the persistent radiative evolution and a statistical study of the burst properties…

High Energy Astrophysical Phenomena · Physics 2015-05-28 Paul Scholz , Victoria M. Kaspi

Early-type stars show a bimodal distribution of magnetic field strengths, with some showing very strong fields ($\gtrsim 1\,\mathrm{kG}$) and others very weak fields ($\lesssim 10\,\mathrm{G}$). Recently, we proposed that this reflects the…

Solar and Stellar Astrophysics · Physics 2021-12-22 Adam S. Jermyn , Matteo Cantiello

Evidence of star-planet interactions in the form of planet-modulated chromospheric emission has been noted for a number of hot Jupiters. Magnetic star-planet interactions involve the release of energy stored in the stellar and planetary…

Earth and Planetary Astrophysics · Physics 2019-07-23 P. Wilson Cauley , Evgenya L. Shkolnik , Joe Llama , Antonino F. Lanza

The properties of matter are significantly modified by strong magnetic fields, $B>>2.35\times 10^9$ Gauss ($1 G =10^{-4} Tesla$), as are typically found on the surfaces of neutron stars. In such strong magnetic fields, the Coulomb force on…

Astrophysics · Physics 2008-11-26 Dong Lai

We derive the expression for the ponderomotive force in the real multicomponent magnetospheric plasma containing heavy ions. The ponderomotive force considered includes the induced magnetic moment of all the species and arises due to…

Plasma Physics · Physics 2015-06-15 A. K. Nekrasov , F. Z. Feygin

Magnetization and its relaxation have been measured on Ba0.6K0.4Fe2As2 single crystals with Tc = 39 K. The magnetization hysteresis loops (MHLs) exhibit flux jumps in the low temperature region, and a second peak-effect in the intermediate…

Superconductivity · Physics 2011-12-01 Bing Shen , Huan Yang , Bin Zeng , Cong Ren , Xibin Xu , Hai-Hu Wen

Voyager 1 has explored the solar wind-interstellar medium interaction region between the terminal shock and heliopause following the intensity distribution of galactic cosmic ray protons above 200 MeV energy. Before this component reached…

Solar and Stellar Astrophysics · Physics 2015-09-09 J. J. Quenby , W. R. Webber

Weak magnetic fields must have existed in the early Universe, as they were sourced by the cross product of electron density and temperature gradients through the Biermann-battery mechanism. In this paper we calculate the magnetic fields…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-15 Nanoom Lee , Yacine Ali-Haimoud

Astronomical observations and isotopic measurements of meteorites suggest that substructures are common in protoplanetary disks and may even have existed in the solar nebula. Here, we conduct paleomagnetic measurements of chondrules in CO…

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