A5006347940- Gamma-ray bursts and supernovae
- SAS software applications and methods
- Astrophysical Phenomena and Observations
- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astronomical Observations and Instrumentation
- Astro and Planetary Science
- Pulsars and Gravitational Waves Research
- Astrophysics and Cosmic Phenomena
- Astrophysics and Star Formation Studies
- Statistical and numerical algorithms
- Galaxies: Formation, Evolution, Phenomena
- Cosmology and Gravitation Theories
- Advanced X-ray and CT Imaging
- Solar and Space Plasma Dynamics
- Geophysics and Gravity Measurements
- Adaptive optics and wavefront sensing
- Particle Detector Development and Performance
- History and Developments in Astronomy
- Advanced Chemical Physics Studies
- Quantum, superfluid, helium dynamics
- Health, psychology, and well-being
- Nuclear Physics and Applications
- Radio Astronomy Observations and Technology
- Relativity and Gravitational Theory
Thüringer Landessternwarte Tautenburg
2015-2024
Max Planck Institute for Extraterrestrial Physics
2009-2016
Excellence Cluster Universe
2009-2011
Technical University of Munich
2009-2011
Instituto de Astrofísica de Canarias
2011
Universidad de La Laguna
2011
University of Iceland
2011
University College Dublin
2009
European Southern Observatory
2009
Clemson University
2001-2009
We have gathered optical photometry data from the literature on a large sample of Swift-era gamma-ray burst (GRB) afterglows including GRBs up to September 2009, for total 76 GRBs, and present an additional three pre-Swift not included in earlier sample. Furthermore, we publish 840 new points 42 GRB afterglows, sets 050319, 050408, 050802, 050820A, 050922C, 060418, 080413A 080810. analyzed light curves all derived spectral energy distributions with best quality, allowing us estimate host...
We describe the construction of GROND, a 7-channel imager, primarily designed for rapid observations gamma-ray burst afterglows. It allows simultaneous imaging in Sloan g' r' i' z' and near-infrared JHK bands. GROND was commissioned at MPI/ESO 2.2 m telescope La Silla (Chile) April 2007, first results its performance calibration are presented.
Gamma-ray bursts (GRBs) have been separated into two classes, originally along the lines of duration and spectral properties, called "short/hard" "long/soft." The latter conclusively linked to explosive deaths massive stars, while former are thought result from merger or collapse compact objects. In recent years, indications accumulating that short/hard versus long/soft division does not map directly onto what would be expected classes progenitors, leading a new classification scheme Type I...
We present multiwavelength observations of the afterglow GRB 130427A, brightest (in total fluence) gamma-ray burst (GRB) past 29 yr. Optical spectroscopy from Gemini-North reveals redshift to be z = 0.340, indicating that its unprecedented brightness is primarily result relatively close proximity Earth; intrinsic luminosities both and are not extreme in comparison other bright GRBs. a large suite spanning 300 s 130 days after demonstrate shows simple, smooth evolution at all frequencies,...
Abstract Gamma-ray bursts (GRBs) are classified into long and short events. Long GRBs (LGRBs) associated with the end states of very massive stars, while (SGRBs) linked to merger compact objects. GRB 200826A was a peculiar event, because by definition it an SGRB, rest-frame duration ∼0.5 s. However, this event energetic soft, which is consistent LGRBs. The relatively low redshift ( z = 0.7486) motivated comprehensive, multiwavelength follow-up campaign characterize its host, search for...
We present the results of a systematic analysis gamma-ray burst afterglow spectral energy distributions (SEDs) in optical/near-infrared bands. Our input list includes entire world sample afterglows observed pre-Swift era by end 2004 that have sufficient publicly available data. apply various dust extinction models to fit SEDs (Milky Way, Large Magellanic Cloud, and Small Cloud) derive corresponding intrinsic GRB host galaxies slopes afterglows. then use these explore parameter space...
We present optical and near-infrared photometry of the afterglow long Gamma-Ray Burst GRB 070802 at redshift 2.45 obtained with ESO/MPI 2.2 m telescope equipped multi-channel imager GROND. Follow-up observations in g'r'i'z' JHK_S bands started ~17 min extended up to 28 h post burst. find an increase brightness early times, which can be explained by superposition reverse forward shock (FS) emission or onset FS. Additionally, we detect a strong broad-band absorption feature i' band, interpret...
We report on the detection by Swift of GRB 080913, and subsequent optical/near-infrared follow-up observations GROND, which led to discovery its optical/NIR afterglow recognition high-z nature via a spectral break between i' z' bands. Spectroscopy obtained at ESO-VLT revealed continuum extending down λ = 9400 Å, zero flux for 7500 Å<λ < we interpret as onset Gunn–Peterson trough z 6.695± 0.025 (95.5% confidence level), making 080913 highest-redshift gamma-ray burst (GRB) date, more distant...
Context. Thirteen years after the discovery of first afterglows, nature dark gamma-ray bursts (GRB) still eludes explanation: while each long-duration GRB typically has an X-ray afterglow, optical/NIR emission is only seen for 40–60% them.
(Abridged) Until recently the information inferred from gamma-ray burst follow-up observations was mostly limited to optically bright afterglows, biasing all demographic studies against sight-lines that contain large amounts of dust. Here, we present GRB afterglow and host for a sample bursts are exemplary previously missed ones because high visual extinction along sight-line. This facilitates an investigation properties, geometry location absorbing dust these poorly-explored galaxies,...
We present data and initial results from VLT/X-Shooter emission-line spectroscopy of 96 galaxies selected by long γ-ray bursts (GRBs) at 0.1 <z< 3.6, the largest sample GRB host spectra available to date. Most our GRBs were detected Swift 76% are 0.5 2.5 with a median zmed ~ 1.6. Based on Balmer and/or forbidden lines oxygen, nitrogen, neon, we measure systemic redshifts, star formation rates (SFR), visual attenuations (AV), oxygen abundances (12 + log (O/H)), widths (σ). study hosts up z...
The first gamma-ray burst (GRB) confirmed to be bright enough seen with the naked eye, GRB 080319B at redshift z = 0.937, allowed for exquisite follow-up observations across electromagnetic spectrum. We present our detailed optical and infrared (IR) of afterglow, consisting over 5000 images starting 51 s after trigger, in concert own analysis Swift UVOT, Burst Alert Telescope (BAT), XRT data. event is extreme not only observed properties but also intrinsically: it was most luminous ever...
We present B-, V-, RC-, IC-, J-, H-, K-, and K'-band observations of the optical transient (OT) associated with GRB 970228, based on a reanalysis previously used images unpublished data. In order to minimize calibration differences, we have collected analyzed most photometry consistently determined magnitude OT relative set secondary field stars. confirm our earlier finding that early decay light curves (before 1997 March 6) was faster than at intermediate times (between 6 April 7). At late...
Context.Before the launch of Swift satellite, majority gamma-ray burst (GRB) afterglows for which Lyα was redshifted into observable spectrum showed evidence a damped absorber. This small sample indicated that GRBs explode either in galaxies, or regions within them, having high neutral hydrogen column densities.