TITLE: GCN CIRCULAR NUMBER: 36041 SUBJECT: LXT 240402A/GRB 240402B: rest-frame energetics from Konus-Wind observation DATE: 24/04/06 14:54:45 GMT FROM: Anna Ridnaia at Ioffe Institute <ridnaia@mail.ioffe.ru> A. Ridnaia, D. Frederiks, A. Lysenko, D. Svinkin, A. Tsvetkova, M. Ulanov, and T. Cline, on behalf of the Konus-Wind team, report: Assuming the spectrum and the observer-frame energetics of GRB 240402B measured by KW (GCN 36028); the redshift of the probable host galaxy z=0.047 (Xu et al., GCN 36016; Levan et al., GCN 36025; Xue at al., GCN 36034); and a standard cosmology with H_0 = 67.3 km/s/Mpc, Omega_M = 0.315, and Omega_Lambda = 0.685 (Planck Collaboration, 2014); we estimate the burst isotropic energy release E_iso to (4.06 ± 0.27)x10^49 erg, the isotropic peak luminosity L_iso to (2.85 ± 0.38)x10^49 erg/s, the rest-frame peak energy of the time-integrated spectrum Ep,i,z to (90 ± 5) keV. With the obtained estimates, GRB 240402B is a low-luminosity outlier in both 'Amati' and 'Yonetoku' relations for the sample of >300 long KW GRBs with known redshifts (Tsvetkova et al., 2017; Tsvetkova et al., 2021), see http://www.ioffe.ru/LEA/GRBs/GRB240402_T31668/GRB240402B_rest_frame.pdf All the quoted errors are estimated at the 90% confidence level. All the presented results are preliminary. View this GCN Circular online at https://gcn.nasa.gov/circulars/36041. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...