Carregant...
Fitxers
Tipus de document
ArticleVersió
Versió publicadaData de publicació
Tots els drets reservats
Si us plau utilitzeu sempre aquest identificador per citar o enllaçar aquest document: https://hdl.handle.net/2445/150806
Very High Energy Gamma-Ray Radiation from the Stellar Mass Black Hole Binary Cygnus X-1
Títol de la revista
Director/Tutor
ISSN de la revista
Títol del volum
Recurs relacionat
Resum
We report on the results from the observations in the very high energy band (VHE; Eγ ≥ 100 GeV) of the black hole X-ray binary (BHXB) Cygnus X-1. The observations were performed with the MAGIC telescope, for a total of 40 hr during 26 nights, spanning the period between 2006 June and November. Searches for steady γ-ray signals yielded no positive result, and upper limits to the integral flux ranging between 1% and 2% of the Crab Nebula flux, depending on the energy, have been established. We also analyzed each observation night independently, obtaining evidence of γ-ray signals at the 4.0 σ significance level (3.2 σ after trial correction) for 154 minutes of effective on-time (EOT) on September 24 between 20:58 and 23:41 UTC, coinciding with an X-ray flare seen by RXTE, Swift, and INTEGRAL. A search for faster-varying signals within a night resulted in an excess with a significance of 4.9 σ (4.1 σ after trial correction) for 79 minutes EOT between 22:17 and 23:41 UTC. The measured excess is compatible with a pointlike source at the position of Cygnus X-1 and excludes the nearby radio nebula powered by its relativistic jet. The differential energy spectrum is well fitted by an unbroken power law described as dN/(dA dt dE) = (2.3 ± 0.6) × 10-12(E/1 TeV)-3.2±0.6. This is the first experimental evidence of VHE emission from a stellar mass black hole and therefore from a confirmed accreting X-ray binary.
Matèries (anglès)
Citació
Citació
MAGIC Collaboration, PAREDES I POY, Josep maria, RIBÓ GOMIS, Marc, BOSCH I RAMON, Valentí. Very High Energy Gamma-Ray Radiation from the Stellar Mass Black Hole Binary Cygnus X-1. _Astrophysical Journal_. 2007. Vol. 665, núm. 51-54. [consulta: 24 de gener de 2026]. ISSN: 0004-637X. [Disponible a: https://hdl.handle.net/2445/150806]