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Pregled bibliografske jedinice broj: 702664

Measurement of the Crab Nebula spectrum over three decades in energy with the MAGIC telescopes


Aleksić, Jelena; ...; Babić, Ana; ...; Dominis Prester, Dijana; ...; Godinović, Nikola; ...; Hrupec, Dario; ... et al.
Measurement of the Crab Nebula spectrum over three decades in energy with the MAGIC telescopes // Journal of High Energy Astrophysics, 5-6 (2015), 30-38 doi:10.1016/j.jheap.2015.01.002 (međunarodna recenzija, članak, znanstveni)


Naslov
Measurement of the Crab Nebula spectrum over three decades in energy with the MAGIC telescopes

Autori
Aleksić, Jelena ; ... ; Babić, Ana ; ... ; Dominis Prester, Dijana ; ... ; Godinović, Nikola ; ... ; Hrupec, Dario ; ... ; Lelas, Damir ; ... ; Puljak, Ivica ; ... ; Šnidarić, Iva ; ... ; Terzić, Tomislav ; ...

Izvornik
Journal of High Energy Astrophysics (2214-4048) 5-6 (2015); 30-38

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
Crab Nebula; Pulsar Wind Nebulae; MAGIC telescopes; Imaging Atmospheric Cherenkov Telescopes; very high energy gamma rays

Sažetak
The MAGIC stereoscopic system collected 69 hours of Crab Nebula data between October 2009 and April 2011. Analysis of this data sample using the latest improvements in the MAGIC stereoscopic software provided an unprecedented precision of spectral and night-by-night light curve determination at gamma rays. We derived a differential spectrum with a single instrument from 50 GeV up to almost 30 TeV with 5 bins per energy decade. At low energies, MAGIC results, combined with Fermi-LAT data, show a flat and broad Inverse Compton peak. The overall fit to the data between 1 GeV and 30 TeV is not well described by a log-parabola function. We find that a modified log-parabola function with an exponent of 2.5 instead of 2 provides a good description of the data (chi-squared/ndf=35/26). Using systematic uncertainties of red the MAGIC and Fermi-LAT measurements we determine the position of the Inverse Compton peak to be at (53 ± 3stat + 31syst -13syst) GeV, which is the most precise estimation up to date and is dominated by the systematic effects. There is no hint of the integral flux variability on daily scales at energies above 300 GeV when systematic uncertainties are included in the flux measurement. We consider three state- of-the-art theoretical models to describe the overall spectral energy distribution of the Crab Nebula. The constant B-field model cannot satisfactorily reproduce the VHE spectral measurements presented in this work, having particular difficulty reproducing the broadness of the observed IC peak. Most probably this implies that the assumption of the homogeneity of the magnetic field inside the nebula is incorrect. On the other hand, the time-dependent 1D spectral model provides a good fit of the new VHE results when considering a 80 {; ; ; ; ; \mu}; ; ; ; ; G magnetic field. However, it fails to match the data when including the morphology of the nebula at lower wavelengths.

Izvorni jezik
Engleski

Znanstvena područja
Fizika



POVEZANOST RADA


Projekt / tema
HRZZ-09/176 - Visokoenergijska astronomija gama zraka teleskopima MAGIC (Nikola Godinović, )

Ustanove
Fakultet elektrotehnike, strojarstva i brodogradnje, Split,
Fakultet elektrotehnike i računarstva, Zagreb,
Institut "Ruđer Bošković", Zagreb,
Sveučilište u Rijeci - Odjel za fiziku

Časopis indeksira:


  • Web of Science Core Collection (WoSCC)
    • Emerging Sources Citation Index (ESCI)
  • Scopus


Uključenost u ostale bibliografske baze podataka:


  • Scopus


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