[AAVSO-HEN] GRB 070508: pseudo-z from 4 different spectral analyses

[grb at aavso.org]

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TITLE:   GCN CIRCULAR
NUMBER:  6405
SUBJECT: GRB 070508: pseudo-z from 4 different spectral analyses
DATE:    07/05/10 16:34:08 GMT
FROM:    Alexandre Pelangeon at LATT,OMP,Toulouse  <alexandre.pelangeon at ast.obs-mip.fr>

A. Pelangeon & J-L. Atteia (LATT-OMP) report:

The intense burst GRB 070508 detected by SWIFT-BAT
(Grupe et al., GCNC 6383) was also observed by other spacecrafts.
Thanks to the published spectral parameters obtained from the different
spectral analyses performed, we have computed 4 pseudo-redshift(**)
for this burst.

Here are the results (the errors on the pseudo-z are at the 90% c.l.):

- From the spectral parameters obtained with the Konus-WIND data
(Golenetskii et al., GCNC 6403)
we obtain: pz = 1.15 +/- 0.15

- From the spectral parameters obtained with the Swift-BAT data
(Barthelmy et al., GCNC 6390; Grupe et al., GCNR 54.1)
we obtain: pz = 1.06 +/- 0.30

- From the spectral parameters obtained with the Suzaku-WAM data
(Uehara et al., GCNC 6396)
we obtain: pz = 1.25 +/- 0.30

- From the spectral parameters obtained with the RHESSI data
(Bellm et al., GCNC 6399)
we obtain: pz = 2.53 +/- 1.40

These values are compatible with the spectroscopic redshift
z=0.82 derived by Jakobsson et al. (GCNC 6398).



(**) cf. http://www.ast.obs-mip.fr/grb/pz