303 citations · 2k across the 33 of their papers we have counts for
31 papers
The GROND gamma-ray burst sample. I. Overview and statistics
J. Greiner, T. Krühler, J. Bolmer +17
A dedicated gamma-ray burst (GRB) afterglow observing program was performed between 2007 and 2016 with GROND, a seven-channel optical and near-infrared imager at the 2.2m telescope…
Quasar clustering at redshift 6
J. Greiner, J. Bolmer, R. M. Yates +4
Large-scale surveys over the last years have revealed about 300 QSOs at redshift above 6. Follow-up observations identified surprising properties, such as the very high black hole…
Observation of inverse Compton emission from a long -ray burst
V. A. Acciari, S. Ansoldi, L. A. Antonelli +301
Long-duration gamma-ray bursts (GRBs) originate from ultra-relativistic jets launched from the collapsing cores of dying massive stars. They are characterised by an initial phase o…
GRB171010A / SN2017htp: a GRB-SN at z=0.33
A. Melandri, D. B. Malesani, L. Izzo +41
The number of supernovae known to be connected with long-duration gamma-ray bursts is increasing and the link between these events is no longer exclusively found at low redshift ($…
New constraints on the physical conditions in H-bearing GRB-host damped Lyman- absorbers
K. E. Heintz, J. Bolmer, C. Ledoux +25
We report the detections of molecular hydrogen (H), vibrationally-excited H (H), and neutral atomic carbon (CI), in two new afterglow spectra of GRBs\,181020A ($z=2.9…
A Reverse Shock in GRB 181201A
Tanmoy Laskar, Hendrik van Eerten, Patricia Schady +26
We present comprehensive multiwavelength radio to X-ray observations of GRB 181201A spanning from s to days after the burst, comprising the first joint AL…
ALMA Detection of a Linearly Polarized Reverse Shock in GRB 190114C
Tanmoy Laskar, Kate D. Alexander, Ramandeep Gill +11
We present ALMA 97.5 GHz total intensity and linear polarization observations of the mm-band afterglow of GRB 190114C spanning 2.2 to 5.2 hours after the burst. We detect linear po…
Signatures of a jet cocoon in early spectra of a supernova associated with a -ray burst
L. Izzo, A. de Ugarte Postigo, K. Maeda +39
Long gamma-ray bursts mark the death of massive stars, as revealed by their association with energetic broad-lined stripped-envelope supernovae. The scarcity of nearby events and t…
Cold gas in the early Universe. Survey for neutral atomic-carbon in GRB host galaxies at 1 < z < 6 from optical afterglow spectroscopy
K. E. Heintz, C. Ledoux, J. P. U. Fynbo +14
We present a survey for neutral atomic-carbon (CI) along gamma-ray burst (GRB) sightlines, which probes the shielded neutral gas-phase in the interstellar medium (ISM) of GRB host…
Evidence for diffuse molecular gas and dust in the hearts of gamma-ray burst host galaxies
J. Bolmer, C. Ledoux, P. Wiseman +17
Here we built up a sample of 22 GRBs at redshifts observed with X-shooter to determine the abundances of hydrogen, metals, dust, and molecular species. This allows us to st…
The 2175 Å extinction feature in the optical afterglow spectrum of GRB 180325A at z=2.25
T. Zafar, K. E. Heintz, J. P. U. Fynbo +26
The UV extinction feature at 2175 Å is ubiquitously observed in the Galaxy but is rarely detected at high redshifts. Here we report the spectroscopic detection of the 2175 Å bump o…
Highly-ionized metals as probes of the circumburst gas in the natal regions of gamma-ray bursts
K. E. Heintz, D. Watson, P. Jakobsson +18
We present here a survey of high-ionization absorption lines in the afterglow spectra of long-duration gamma-ray bursts (GRBs) obtained with the VLT/X-shooter spectrograph. Our mai…
X-shooter and ALMA spectroscopy of GRB 161023A - A study of metals and molecules in the line of sight towards a luminous GRB
A. de Ugarte Postigo, C. C. Thöne, J. Bolmer +45
Long gamma-ray bursts are produced during the dramatic deaths of massive stars with very short lifetimes, meaning that they explode close to the birth place of their progenitors. D…
VLT/X-shooter GRBs: Individual extinction curves of star-forming regions
T. Zafar, D. Watson, P. Møller +14
The extinction profiles in Gamma-Ray Burst (GRB) afterglow spectral energy distributions (SEDs) are usually described by the Small Magellanic Cloud (SMC)-type extinction curve. In…
GRB 151027B - large-amplitude late-time radio variability
J. Greiner, J. Bolmer, M. Wieringa +20
Deriving physical parameters from gamma-ray burst afterglow observations remains a challenge, even now, 20 years after the discovery of afterglows. The main reason for the lack of…
A Gravitationally Lensed Quasar Discovered in OGLE
Z. Kostrzewa-Rutkowska, S. Kozłowski, C. Lemon +15
We report the discovery of a new gravitationally lensed quasar (double) from the Optical Gravitational Lensing Experiment (OGLE) identified inside the 670 sq. deg area encomp…
Dust reddening and extinction curves towards gamma-ray bursts at z > 4
Jan Bolmer, Jochen Greiner, Thomas Krühler +4
Dust is known to be produced in the envelopes of AGB stars, the expanded shells of supernova (SN) remnants, and in situ grain growth in the ISM, although the corresponding efficien…
Colour variations in the GRB 120327A afterglow
A. Melandri, S. Covino, E. Zaninoni +42
We present a comprehensive temporal and spectral analysis of the long Swift GRB 120327A afterglow data to investigate the possible causes of the observed early time colour variatio…
The host galaxy of the short GRB111117A at : impact on the short GRB redshift distribution and progenitor channels
J. Selsing, T. Krühler, D. Malesani +26
It is notoriously difficult to localize short -ray bursts (sGRBs) and their hosts to measure their redshifts. These measurements, however, are critical to constrain the nature o…
New High-z Fermi BL Lacs with the Photometric Dropout Technique
A. Kaur, A. Rau, M. Ajello +6
Determining redshifts for BL Lacertae (BL Lac) objects using the traditional spectroscopic method is challenging due to the absence of strong emission lines in their optical spectr…
The evolution of superluminous supernova LSQ14mo and its interacting host galaxy system
T. -W. Chen, M. Nicholl, S. J. Smartt +26
We present and analyse an extensive dataset of the superluminous supernova (SLSN) LSQ14mo (z = 0.256), consisting of a multi-colour lightcurve from -30 d to +70 d in the rest-frame…
Evolution of the dust-to-metals ratio in high-redshift galaxies probed by GRB-DLAs
P. Wiseman, P. Schady, J. Bolmer +4
Context. Several issues regarding the nature of dust at high redshift remain unresolved: its composition, its production and growth mechanisms, and its effect on background sources…
OGLE16aaa - a Signature of a Hungry Super Massive Black Hole
Łukasz Wyrzykowski, M. Zieliński, Z. Kostrzewa-Rutkowska +22
We present the discovery and first three months of follow-up observations of a currently on-going unusual transient detected by the OGLE-IV survey, located in the centre of a galax…
A very luminous magnetar-powered supernova associated with an ultra-long gamma-ray burst
Jochen Greiner, Paolo A. Mazzali, D. Alexander Kann +29
A new class of ultra-long duration (>10,000 s) gamma-ray bursts has recently been suggested. They may originate in the explosion of stars with much larger radii than normal long ga…