303 citations · 2k across the 33 of their papers we have counts for
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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…
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…
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…
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…
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…
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…
Super-solar metallicity at the position of the ultra-long GRB130925A
P. Schady, T. Kruehler, J. Greiner +17
Over the last decade there has been immense progress in the follow-up of short and long GRBs, resulting in a significant rise in the detection rate of X-ray and optical afterglows,…
GRB hosts through cosmic time - VLT/X-Shooter emission-line spectroscopy of 96 GRB-selected galaxies at 0.1 < z < 3.6
T. Krühler, D. Malesani, J. P. U. Fynbo +41
[Abridged] We present data and initial results from VLT/X-Shooter emission-line spectroscopy of 96 GRB-selected galaxies at 0.1<z<3.6, the largest sample of GRB host spectroscopy a…
The mysterious optical afterglow spectrum of GRB140506A at z=0.889
J. P. U. Fynbo, T. Krühler, K. Leighly +40
Context. Gamma-ray burst (GRBs) afterglows probe sightlines to star-forming regions in distant star-forming galaxies. Here we present a study of the peculiar afterglow spectrum of…