109,127 research outputs found

    Study on the spectrum of the injected relativistic protons

    Full text link
    About 10TeV gamma-ray emission within 10 pc region from the Galactic Center had been reported by 4 independent groups. Considering that this TeV gamma-ray emission is produced via a hadronic model, and the relativistic protons came from the tidal disruption of stars by massive black holes, we investigate the spectral nature of the injected relativistic protons required by the hadronic model. The calculation was carried on the tidal disruption of the different types of stars and the different propagation mechanisms of protons in the interstellar medium. Compared with the observation data from HESS, we find for the best fitting that the power-law index of the spectrum of the injected protons is about -1.9, when a red giant star is tidally disrupted, and the effective confinement of protons diffusion mechanism is adopted.Comment: 2 pages, IAU Symposium 25

    Risk Management: Lessons Learned From the Snow Crisis in China

    Get PDF

    Coexistence of superconductivity and charge-density-wave domain in 1T1T-Fex_xTa1x_{1-x}SSe

    Full text link
    A series of 1T1T-Fex_xTa1x_{1-x}SSe (0 x\leq x \leq 0.1) single crystals was fabricated via the chemical-vapor-transport (CVT) method and investigated by structure, transport, and magnetic measurements along with the density-functional-theory (DFT) calculations. The superconductivity (SC) in parent 1T1T-TaSSe can be gradually suppressed by Fe-substitution (x0.03x\leq0.03), accompanied by the disappearance of charge-density-wave (CDW). DFT calculations show that the Fe-substitution effectively inhibits the CDW superstructure and thereby the CDW domains are destroyed. With further increasing xx (x>0.03x>0.03), the disorder-induced scattering increases, and the system enters into the possible Anderson localization (AL) state. Our results prove the SC develops in the CDW phase and coexists with the CDW domain in 1T1T-TaSSe system
    corecore