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Summary Information

Light curve

Hide the light curve section.

This light curve comes from the light curve repository (if you use it, please cite Evans et al [2007, 2009]. Flares, marked by cross-hatched regions, are identified automatically, but may have been manually corrected. These are excluded from the fit. Any power-law breaks added to the fit must be required at the 4-σ level (according to an f-test) to be included in the best-fit. Details of all fits attempted are given below the plot. For more information see the light curve fitting documentation.

Fit Details

Nbreaks	χ2	dof	Comments	Image
0	1093	97
1	1084	95	Break significance <4-σ (67.04 % probability of chance improvement)
2	136	93	Break required. (4.06e-39 % probability of chance improvement). This is the best fit.
3	127	91	Break significance <4-σ (3.94 % probability of chance improvement)
4	120	89	Break significance <4-σ (2.56 % probability of chance improvement)

There are no flares ignored from this fit.

The best-fitting light curve has 2 breaks.

Click on the number of breaks in the table to the right to change which fit is plotted above and detailed below.

Currently showing the best fit.

α1	1.35 (+0.17, -0.35)
Tb,1	124 (+17, -20) s
α2	2.7 (+0.3, -0.3)
Tb,2	271 (+57, -52) s
α3	6.23 (+1.27, -0.52)

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Spectra

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Spectra have been created for each power-law segment in the best fitting light curve (shown above). Times of flaring have not been removed, however this makes little difference to most spectra (see Fig 7/8c of Evans et al. 2009). For more information see the time-resolved spectroscopy documentation.

Jump to: phase1|phase2|phase3

phase1 spectrum (T0 + 79 to 123 s)

Download spectral files for phase1 spectrum.

Plots to download

• wt mode ps file
• wt mode gif file

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phase2 spectrum (T0 + 123 to 271 s)

Download spectral files for phase2 spectrum.

Plots to download

• both modes ps file
• both modes gif file
• wt mode ps file
• wt mode gif file
• pc mode ps file
• pc mode gif file

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phase3 spectrum (T0 + 271 to 257603 s)

Download spectral files for phase3 spectrum.

Plots to download

• pc mode ps file
• pc mode gif file

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Comparison with other bursts

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Parameter distributions

The plots below show the probability density functions of the temporal and time-averaged spectral parameters for all GRBs, with the data for GRB 211227A shown on in colour. Click the images for larger versions.

For all plots, the solid vertical lines mark the values for this GRB, and the dashed lines the 1-σ uncertainties. For α and T_b, the colour changes for each phase. For the spectral parameters, the WT fits are shown in blue and the PC in red. These figures correspond to Figs. 5,6, 7a and 8a of Evans et al. (2009). See the PDF documentation for more information.

Temporal indices	Break Times	NH	Spectral indices

Closure Relationships

The plots below show (α, β) scatter plots for each of the different types/phases of light curves (see light-curve types), since GRB 211227A is of type, "Oddball," which has no scatter plots of its own. GRB 211227A is shown in colour, with each light curve phase, or XRT mode marked by a different colour. α and β are the temporal and spectral energy power-law indices respectively. The shaded regions mark those allowed by the standard closure relationships. These figures correspond to Fig. 10 of Evans et al. (2009). See the closure relationship documentation for more information.

No break
One-break, steep first Steep phase	One-break, steep first Shallow phase
One-break, shallow first Shallow phase	One-break, shallow first Steep phase
Canonical Steep phase	Canonical Plateau	Canonical 'Normal'	Canonical Post jet-break

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Last updated 2023 Aug 01 at 15:31:06 UT
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