Log-Normal Distributions in Cygnus X-1: Possible Physical Link with Gamma-Ray Bursts and Blazars

Abstract

Prompted by recent discoveries of log-normal distributions in gamma-ray/X-ray temporal variabilities of gamma-ray bursts (GRBs) and blazars, we re-examine the X-ray variability of Cygnus X-1 in the hard/low state using Ginga data in 1990. It was previously reported that the distributions of the time intervals between X-ray shots (flares) deviated from the Poisson distributions at short time intervals: the occurrence of shots tended to be suppressed for several seconds before and/or after a shot event. Detailed analyses show that this deviation is larger for shots with larger peaks, and that the time-interval distributions for large shots approach log-normal distributions with a peak at the interval of 7--8 s. Furthermore, we also show that the peak-intensity distribution for the shots is consistent with the log-normal distribution, though no typical peak intensity can be seen. This might indicate the presence of a physical link connecting the physics of black hole accretion flow and that of jet/GRB formation.

5 pages 3 figures: accepted for publication in PASJ

References in corpus (4)

• Accretion Models of Gamma-Ray Bursts
• Time Scales in Long GRBs
• Temporal properties of gamma-ray bursts as signatures of jets from the central engine
• Two-Dimensional Hydrodynamic Simulations of Convection in Radiation-Dominated Accretion Disks

Cited by in corpus (15)

• Binary Black Hole Accretion Flows in Merged Galactic Nuclei
• Global Three-Dimensional Simulations of Black Hole Accretion Disks: X-ray Flares in the Plunging Region
• Testing the Propagating Fluctuations Model with a Long, Global Accretion Disk Simulation
• Gamma-ray Flux Distribution and Non-linear behavior of Four LAT Bright AGNs
• Evidence for two Lognormal States in Multi-wavelength Flux Variation of FSRQ PKS 1510-089
• Propagating mass accretion rate fluctuations in X-ray binaries under the influence of viscous diffusion
• Non-Linear Dynamics of Accretion Disks with Stochastic Viscosity
• Study of long-term flux and photon Index distributions of blazars using RXTE observations
• The accretion flow geometry of MAXI J1820+070 through broadband noise research with Insight-HXMT
• Understanding the General Feature of Microvariability in $Kepler$ Blazar W2R 1926$+$42
• Statistical analysis of variability properties of the Kepler blazar W2R 1926+42
• On the origin of multifrequency temporal and spectral variability in Ton 599
• Searching for similarities in the accretion flow of Seyfert 1 galaxies and cataclysmic variables based on flare profiles of IRAS 13224-3809, 1H 0707-495, Mrk 766 and MV Lyr
• A new algorithm for detecting X-ray shots in Cyg X-1
• Evolution of X-ray and optical rapid variability during the low/hard state in the 2018 outburst of MAXI J1820+070 = ASASSN-18ey