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Swift-XRT spectra of GRB 250221A

Last updated after receiving ObsID 01290305002, version 11

Data were analysed using HEASOFT version 6.35.2

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Add time-sliced spectrum.

The spectral fits assume a redshift: 0.768 (GCN 39418)

Jump to: Time-averaged|Late Time

Time-averaged spectrum (T0 + 126 to 28522 s)

Download spectral files for Time-averaged spectrum.

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WT and PC mode spectra of Time-averaged

WT mode. Mean photon arrival: T0+129 s

N_H (Galactic)	3.73 × 10²⁰ cm^-2
N_H (intrinsic)	0 (+4.62 × 10²¹, -0) cm^-2
z of absorber	0.768
Photon index	3.15 (+1.86, -0.66)
Flux (0.3-10 keV) (Observed)	1.3 (+0.6, -0.5) × 10^-10 erg cm^-2 s^-1
Flux (0.3-10 keV) (Unabsorbed)	1.6 (+4.3, -0.6) × 10^-10 erg cm^-2 s^-1
Counts to flux (obs)	2.13 × 10^-11 erg cm^-2 ct^-1
Counts to flux (unabs)	2.74 × 10^-11 erg cm^-2 ct^-1
W-stat (dof) What's this?	13.36 (18)
Spectrum exposure	5 s

PC mode. Mean photon arrival: T0+3260 s

N_H (Galactic)	3.73 × 10²⁰ cm^-2
N_H (intrinsic)	3.3 (+2.1, -1.8) × 10²¹ cm^-2
z of absorber	0.768
Photon index	2.08 (+0.22, -0.20)
Flux (0.3-10 keV) (Observed)	3.6 (+0.5, -0.4) × 10^-12 erg cm^-2 s^-1
Flux (0.3-10 keV) (Unabsorbed)	4.7 (+0.5, -0.5) × 10^-12 erg cm^-2 s^-1
Counts to flux (obs)	3.32 × 10^-11 erg cm^-2 ct^-1
Counts to flux (unabs)	4.34 × 10^-11 erg cm^-2 ct^-1
W-stat (dof) What's this?	178.30 (222)
Spectrum exposure	5.8 ks

Late Time spectrum (T0 + 4278 to 28522 s)

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PC mode spectrum of Late Time

PC mode. Mean photon arrival: T0+9502 s

N_H (Galactic)	3.73 × 10²⁰ cm^-2
N_H (intrinsic)	6 (+5, -4) × 10²¹ cm^-2
z of absorber	0.768
Photon index	2.1 (+0.4, -0.4)
Flux (0.3-10 keV) (Observed)	1.18 (+0.30, -0.23) × 10^-12 erg cm^-2 s^-1
Flux (0.3-10 keV) (Unabsorbed)	1.71 (+0.47, -0.30) × 10^-12 erg cm^-2 s^-1
Counts to flux (obs)	3.44 × 10^-11 erg cm^-2 ct^-1
Counts to flux (unabs)	4.97 × 10^-11 erg cm^-2 ct^-1
W-stat (dof) What's this?	98.14 (96)
Spectrum exposure	5.3 ks