Long-duration γ-ray bursts (GRBs) at z < 1 are in most cases found to be accompanied by bright, broad-lined Type Ic supernovae (SNe Ic-BL). The highestenergy GRBs are mostly located at higher redshifts, where the associated SNe are hard to detect observationally. Here we present early and late observations of

We report on multiwavelength observations, ranging from X-ray to radio wave bands, of the IPN-localized gammaray burst GRB 070125. Spectroscopic observations reveal the presence of absorption lines due to O i, Si ii, and C iv, implying a likely redshift of z ¼ 1:547. The well-sampled light curves, in particular from 0.5 to 4 days after the burst, suggest a jet break at 3.7 days, corresponding to a jet opening angle of $7.0 , and implying an intrinsic GRB energy in the 1Y10,000 keV band of around E ¼ (6:3Y 6:9) ; 10 51 ergs (based on the fluences measured by the gamma-ray detectors of the IPN). GRB 070125 is among the brightest afterglows observed to date. The SED implies a host extinction of A V < 0:9 mag. Two rebrightening episodes are observed, one with excellent time coverage, showing an increase in flux of 56% in $8000 s. The evolution of the afterglow light curve is achromatic at all times. Late-time observations of the afterglow do not show evidence for emission from an underlying host galaxy or supernova. Any host galaxy would be subluminous, consistent with current GRB host galaxy samples. Evidence for strong Mg ii absorption features is not found, which is perhaps surprising in view of the relatively high redshift of this burst and the high likelihood for such features along GRB-selected lines of sight.

We here report a spectroscopic monitor for the supernova SN 2017iuk associated with the long-duration lowluminosity gamma-ray burst GRB 171205A at a redshift of 0.037, which is up to now the third GRB-SN event away from us. Our spectroscopic observations and spectral analysis allow us to identify SN 2017iuk as a typical broad-line type Ic SN. A comparison study suggests that the type-IcBL SN 2017iuk resembles to SN 2006aj in following aspects: 1) similar spectra at the nearby epochs, 2) comparable evolution of the photospheric velocity obtained from the measurements based on both Si IIλ6355 line and spectral modeling, and 3) comparable explosion parameters. This analogy could imply a formation of a neutron star in the core-collapse of GRB 171205A/SN 2017iuk as previously suggested in GRB 060218/SN 2006aj. The properties of the host galaxy is discussed, which suggests that GRB 171205A/SN 2017iuk occurred in an early type (S0), high-mass, starforming galaxy with low specific SFR and solar metallicity.