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Swift-XRT spectra of GRB 250818A

Last updated after receiving ObsID 01343270001, version 15

Data were analysed using HEASOFT version 6.35.2

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Jump to: Time-averaged|Late Time

Time-averaged spectrum (T0 + 101 to 77442 s)

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WT and PC mode spectra of Time-averaged

WT mode. Mean photon arrival: T0+170 s

N_H (Galactic)	6.81 × 10²¹ cm^-2
N_H (intrinsic)	9.5 (+0.8, -0.8) × 10²¹ cm^-2
z of absorber	0
Photon index	2.18 (+0.06, -0.06)
Flux (0.3-10 keV) (Observed)	4.04 (+0.10, -0.09) × 10^-9 erg cm^-2 s^-1
Flux (0.3-10 keV) (Unabsorbed)	9.9 (+0.6, -0.5) × 10^-9 erg cm^-2 s^-1
Counts to flux (obs)	5.01 × 10^-11 erg cm^-2 ct^-1
Counts to flux (unabs)	1.23 × 10^-10 erg cm^-2 ct^-1
W-stat (dof) What's this?	743.02 (753)
Spectrum exposure	224 s

PC mode. Mean photon arrival: T0+17052 s

N_H (Galactic)	6.81 × 10²¹ cm^-2
N_H (intrinsic)	1.01 (+0.25, -0.23) × 10²² cm^-2
z of absorber	0
Photon index	1.76 (+0.17, -0.16)
Flux (0.3-10 keV) (Observed)	5.8 (+0.4, -0.4) × 10^-11 erg cm^-2 s^-1
Flux (0.3-10 keV) (Unabsorbed)	1.022 (+0.125, -0.091) × 10^-10 erg cm^-2 s^-1
Counts to flux (obs)	6.57 × 10^-11 erg cm^-2 ct^-1
Counts to flux (unabs)	1.15 × 10^-10 erg cm^-2 ct^-1
W-stat (dof) What's this?	495.30 (526)
Spectrum exposure	5.2 ks

Late Time spectrum (T0 + 4396 to 77442 s)

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PC mode spectrum of Late Time

PC mode. Mean photon arrival: T0+18350 s

N_H (Galactic)	6.81 × 10²¹ cm^-2
N_H (intrinsic)	1.09 (+0.27, -0.25) × 10²² cm^-2
z of absorber	0
Photon index	1.80 (+0.18, -0.17)
Flux (0.3-10 keV) (Observed)	5.5 (+0.4, -0.4) × 10^-11 erg cm^-2 s^-1
Flux (0.3-10 keV) (Unabsorbed)	9.91 (+1.35, -0.97) × 10^-11 erg cm^-2 s^-1
Counts to flux (obs)	6.55 × 10^-11 erg cm^-2 ct^-1
Counts to flux (unabs)	1.19 × 10^-10 erg cm^-2 ct^-1
W-stat (dof) What's this?	471.01 (511)
Spectrum exposure	5.1 ks