The Internal Luminosity Function And Grb Properties

The Internal Luminosity Function (ILF) is the distribution of luminosity within a gamma-ray burst and is thus an intrinsic burst property. The ILF of most bursts can be described accurately using a power-law index modified by a power-law curvature parameter. A flat power-law index indicates a large amount of high luminosity emission relative to low luminosity emission, while a steep power-law index indicates a large amount of low luminosity emission relative to high luminosity emission. Bursts with steep power-law indices tend to show large ILF curvatures, indicating that they are also deficient in lower-luminosity emission. The ILF anticorrelates with duration and fluence, indicating that bursts with large ILF curvatures are longer and brighter (as measured by fluence) than bursts emitting a broad range of luminosities. The ILF might be an indicator of Long vs. Short GRB class.