DE UGARTE POSTIGO , A.

Laser Guide Star Adaptive Optics (LGS-AO) is becoming routine in several astronomical observatories. The use of powerful lasers generates sensible Raman emissions on the uplink laser beam path, plus secondary Rayleigh scattering from atmospheric molecules and Mie scattering from aerosols. This paper reports the results of a campaign done with...

We observed again the optical afterglow of GRB 210112A (Swfit detection: Ambrosi et al., GCN #29289; AGILE Detection: Ursi et al., GCN #29293) with the 1.5m telescope of the Observatorio de Sierra Nevada (OSN), Granada, Spain. We obtained 3 x 450 s exposures in B, V, Rc each, and 8 x 150 s in Ic, between 2021-01-13 04:29:28.99 and 2021-01-13...

We observed the optical afterglow of GRB 210112A (Swfit detection: Ambrosi et al., GCN #29289; AGILE Detection: Ursi et al., GCN #29293) with the 1.5m telescope of the Observatorio de Sierra Nevada (OSN), Granada, Spain. We obtained 12 x 90 s exposures in B, Rc, Ic and 11 x 90 s in V, between 2021-01-12 04:03:22.52 and 2021-01-12 05:21:34.99...

We observed the fast-fading hostless transient ZTF21aaeyldq (Ho et al., GCN #29305) with OSIRIS at the 10.4m Gran Telescopio Canarias (Roque de los Muchachos Observatory, La Palma, Canary Islands, Spain), starting at 2021-01-16 23:35:54.359 UT (16.60 hours after the first optical detection). The source is clearly detected. We obtained a 60 s...

We report on multi-band observations of the transient source Swift J0840.7−3516, which was detected in outburst in 2020 February by the Neil Gehrels Swift Observatory. The outburst episode lasted just ∼5 days, during which the X-ray luminosity quickly decreased from L X ≈ 3 × 10 37 d 10 2 erg s −1 at peak down to L X ≈ 5 × 10 33 d 10 2 erg s −1...

The supernovae (SNe) associated with gamma-ray bursts (GRBs) are generally seen as a homogenous population, but at least one exception exists, both in terms of luminosity as well as Spectral Energy Distribution (SED). However, this event, SN 2011kl, was associated with an ultra-long GRB 111209A. Do such outliers also exist for more typical...

We present a detailed analysis of short GRB 201221D lying at redshift z = 1.045. We analyse the high-energy data of the burst and compare it with the sample of short gamma-ray bursts (SGRBs). The prompt emission characteristics are typical of those seen in the case of other SGRBs except for the peak energy (E_p), which lies at the softer end...

Abstract We present radio and optical afterglow observations of the TeV-bright long Gamma Ray Burst (GRB) 190114C at a redshift of z = 0.425, which was detected by the MAGIC telescope. Our observations with ALMA, ATCA, and uGMRT were obtained by our low frequency observing campaign and range from ∼1 to ∼140 days after the burst and the optical...

We present a detailed analysis of short GRB 201221D lying at redshift $z= 1.045$. We analyse the high-energy data of the burst and compare it with the sample of short gamma-ray bursts (SGRBs). The prompt emission characteristics are typical of those seen in the case of other SGRBs except for the peak energy ($E_{\rm p}$), which lies at the...

Long GRB hosts at z < 1 are usually low-mass, low-metallicity star-forming galaxies. Here we present the most detailed, spatially resolved study of the host of GRB 171205A so far, a grand-design barred spiral galaxy at z = 0.036. Our analysis includes MUSE integral field spectroscopy complemented with high-spatial-resolution UV/VIS HST imaging...

Short Gamma-Ray Bursts (SGRBs) are produced by the coalescence of compact binary systems which are remnants of massive stars. GRB 160410A is classified as a short-duration GRB with extended emission and is currently the farthest SGRB with a redshift determined from an afterglow spectrum and also one of the brightest SGRBs to date. The fast...