HETE Burst H3889

Burst H3889 summary

  • Trigger time is
    • UTC=20050807_105844
    • GRB=GRB050807+39524
  • Triggering instrument was Fregate
  • Trigger timescale was 1.3 seconds
  • Trigger detected in 30-400 keV band

Evaluation GRB050807

Long GRB.

Download ASCII table of Fregate Band A, B, C lightcurves here.

The color of trigger H3889, defined by the ratio of total counts in Fregate band C (30-400 keV) to band A (7-40 keV) vs. band B (7-80 keV) to band A, overlaid on a the color-color plot of all localized bursts detected to date. Note the separation of XRFs, XRRs, and GRBs.

The signal to noise in Fregate band C (30-400 keV) of trigger H3889 in relation to the S/N of band C of other localized HETE triggers. We find empirically that most XRFs are faint and soft: the fact that localized bursts require a minimum S/N in the 2-25 keV band means that the band C S/N should be low. We find a cutoff in the band C S/N of 6.5 delineates the XRF/non-XRF population with high reliability.

An automated fit of a cutoff power-law spectrum has been performed for H3889. The fit of the model to the data is shown below; the calculated values of Epeak and the burst fluence (25-100 keV) are:

	Epeak    = 171.41 keV
	Fluence  = 3.989e-06 erg/cm^2
	Duration = 25.300 seconds
	PseudoZ  = 1.730


These results are computed by an automatic script. Please visually inspect the XSPEC summary plot to judge the quality of the results.

Please note that this value of Epeak results from a fit to FREGATE data (8-400 keV) only -- a more reliable joint fit to FREGATE and WXM data is not yet automated. As such, this Epeak estimate is likely to be biased high, especially for soft events, such as XRFs. In our experience, the inclusion of WXM data can lower the value of E_peak substantially. The above Epeak value should thus be viewed as a preliminary estimate. As better fits become available, the information will be posted here.

Click here for an explanation of the method.

Skymap for HETE trigger H3889

Link to Jochen Greiner's web page on GRB050807