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Swift-XRT spectra of GRB 250818B

Last updated after receiving ObsID 03000030001, version 5

Data were analysed using HEASOFT version 6.35.2

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Add time-sliced spectrum.

The spectral fits assume a redshift: 1.216 (GCN 41419)

Jump to: Time-averaged|Late Time

Time-averaged spectrum (T0 + 1683 to 6571 s)

Download spectral files for Time-averaged spectrum.

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PC mode spectrum of Time-averaged

PC mode. Mean photon arrival: T0+3514 s

N_H (Galactic)	6.49 × 10²⁰ cm^-2
N_H (intrinsic)	6 (+6, -6) × 10²⁰ cm^-2
z of absorber	1.216
Photon index	1.90 (+0.21, -0.20)
Flux (0.3-10 keV) (Observed)	1.75 (+0.22, -0.19) × 10^-11 erg cm^-2 s^-1
Flux (0.3-10 keV) (Unabsorbed)	2.16 (+0.22, -0.17) × 10^-11 erg cm^-2 s^-1
Counts to flux (obs)	3.61 × 10^-11 erg cm^-2 ct^-1
Counts to flux (unabs)	4.45 × 10^-11 erg cm^-2 ct^-1
W-stat (dof) What's this?	236.05 (247)
Spectrum exposure	1.6 ks

Late Time spectrum (T0 + 5734 to 6571 s)

Download spectral files for Late Time spectrum.

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PC mode spectrum of Late Time

PC mode. Mean photon arrival: T0+6145 s

N_H (Galactic)	6.49 × 10²⁰ cm^-2
N_H (intrinsic)	5.5 (+10.8, -5.5) × 10²⁰ cm^-2
z of absorber	1.216
Photon index	2.1 (+0.4, -0.3)
Flux (0.3-10 keV) (Observed)	1.10 (+0.24, -0.19) × 10^-11 erg cm^-2 s^-1
Flux (0.3-10 keV) (Unabsorbed)	1.41 (+0.25, -0.22) × 10^-11 erg cm^-2 s^-1
Counts to flux (obs)	3.31 × 10^-11 erg cm^-2 ct^-1
Counts to flux (unabs)	4.24 × 10^-11 erg cm^-2 ct^-1
W-stat (dof) What's this?	107.88 (120)
Spectrum exposure	837 s