P. Jakobsson
A5011808072- Gamma-ray bursts and supernovae
- SAS software applications and methods
- Stellar, planetary, and galactic studies
- Astrophysical Phenomena and Observations
- Astronomy and Astrophysical Research
- Astronomical Observations and Instrumentation
- Astro and Planetary Science
- Pulsars and Gravitational Waves Research
- Galaxies: Formation, Evolution, Phenomena
- Astrophysics and Cosmic Phenomena
- Astrophysics and Star Formation Studies
- Microbial Metabolites in Food Biotechnology
- CCD and CMOS Imaging Sensors
- Spectroscopy and Chemometric Analyses
- Advanced X-ray and CT Imaging
- Particle Detector Development and Performance
- Cosmology and Gravitation Theories
- Statistical and numerical algorithms
- Atmospheric Ozone and Climate
- Adaptive optics and wavefront sensing
- Statistical Mechanics and Entropy
- Heusler alloys: electronic and magnetic properties
- Radioactive Decay and Measurement Techniques
- Advancements in PLL and VCO Technologies
- Nuclear Physics and Applications
University of Iceland
2015-2024
Reykjavík University
2017
University of Copenhagen
2001-2011
Yunnan Observatories
2010-2011
Chinese Academy of Sciences
2010-2011
Max Planck Institute for Extraterrestrial Physics
2011
Excellence Cluster Universe
2011
Technical University of Munich
2011
Instituto de Astrofísica de Canarias
2011
Universidad de La Laguna
2011
Abstract We report the discovery and monitoring of near-infrared counterpart (AT2017gfo) a binary neutron-star merger event detected as gravitational wave source by Advanced Laser Interferometer Gravitational-wave Observatory (LIGO)/Virgo (GW170817) short gamma-ray burst Fermi Gamma-ray Burst Monitor (GBM) Integral SPI-ACS (GRB 170817A). The evolution transient light is consistent with predictions for behavior “kilonova/macronova” powered radioactive decay massive neutron-rich nuclides...
Gamma-ray bursts (GRBs) serve as powerful probes of the early Universe, with their luminous afterglows revealing locations and physical properties star forming galaxies at highest redshifts, potentially locating first generation (Population III) stars. Since GRB have intrinsically very simple spectra, they allow robust redshifts from low signal to noise spectroscopy, or photometry. Here we present a photometric redshift z~9.4 for Swift-detected 090429B based on deep observations...
Variable X-ray and gamma-ray emission is characteristic of the most extreme physical processes in Universe, studying sources these energetic photons has been a major driver astronomy for past 50 years. Here we present multiwavelength observations unique selected transient, discovered by Swift, which was accompanied bright across electromagnetic spectrum, whose properties are unlike any previously observed source. We pinpoint event to center small, star-forming galaxy at redshift z=0.3534....
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...
(Abridged). We present a sample of 77 optical afterglows (OAs) Swift detected GRBs for which spectroscopic follow-up observations have been secured. provide linelists and equivalent widths all lines redward Ly-alpha. discuss to what extent the current bursts with OA spectroscopy is biased subsample GRBs. For that purpose we define an X-ray selected optimal conditions ground-based follow up from period March 2005 September 2008; 146 fulfill our criteria. derive redshift distribution this...
We present comprehensive multiwavelength observations of three gamma-ray bursts (GRBs) with durations several thousand seconds. demonstrate that these events are extragalactic transients; in particular we resolve the long-standing conundrum distance GRB 101225A (the "Christmas-day burst"), finding it to have a redshift z=0.847, and showing two apparently similar (GRB 111209A 121027A) lie at z=0.677 z=1.773 respectively. The systems show extremely unusual X-ray optical lightcurves, very...
The mergers of binary compact objects such as neutron stars and black holes are central interest to several areas astrophysics, including the progenitors gamma-ray bursts (GRBs), sources high-frequency gravitational waves likely production sites for heavy element nucleosynthesis via rapid capture (the r-process). These elements include some great geophysical, biological cultural importance, thorium, iodine gold. Here we present observations exceptionally bright burst GRB 230307A. We show...
Primordial neutral atomic gas, mostly composed of hydrogen, is the raw material for star formation in galaxies. However, there are few direct constraints on amount hydrogen (H i ) galaxies at early cosmic times. We analyzed James Webb Space Telescope (JWST) near-infrared spectroscopy distant galaxies, redshifts ≳8. From a sample 12 we identified three that show strong damped Lyman-α absorption due to H their local surroundings. The located spectroscopic 8.8, 10.2, and 11.4, corresponding 400...
The exceptionally high luminosities of gamma-ray bursts (GRBs), gradually emerging as extremely useful probes star formation, make them promising tools for exploration the high-redshift Universe. Here we present a carefully selected sample Swift GRBs, intended to estimate in an unbiased way GRB mean redshift (), constraints on fraction and upper limit heavily obscured afterglows. We find that at least 7% GRBs originate . In addition, consistent with pre-Swift observations, most 20%...
Aims.We present early optical spectroscopy of the afterglow gamma-ray burst GRB 060206 with aim determining metallicity absorber and physical conditions in circumburst medium. We also discuss how GRBs may be important complementary probes cosmic chemical evolution.
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...
We report the Swift discovery of nearby long, soft gamma-ray burst GRB 100316D, and subsequent unveiling its low redshift host galaxy associated supernova. derive event to be z = 0.0591 +/- 0.0001 provide accurate astrometry for GRB-SN. study extremely unusual prompt emission with time-resolved X-ray spectroscopy, find that spectrum is best modelled a thermal component in addition synchrotron peak energy. The light curve has remarkably shallow decay out at least 800 s. bright, blue highly...
Aims.We present a study of the optical and near-infrared (NIR) properties Type Ia Supernova (SN Ia) 2003du.
We present observations and analysis of the host galaxies 23 heavily dust-obscured gamma-ray bursts (GRBs) observed by Swift satellite during years 2005–2009, representing all GRBs with an unambiguous host-frame extinction AV > 1 mag from this period. Deep Keck, Gemini, Very Large Telescope, Hubble Space Spitzer successfully detect establish spectroscopic or photometric redshifts for events, enabling us to provide measurements intrinsic star formation rates, stellar masses, mean extinctions....
Abstract We present Hubble Space Telescope ( HST ) and Chandra imaging, combined with Very Large MUSE integral field spectroscopy of the counterpart host galaxy first binary neutron star merger detected via gravitational-wave emission by LIGO Virgo, GW170817. The galaxy, NGC 4993, is an S0 at z = 0.009783. There evidence for large, face-on spiral shells in continuum edge-on features visible nebular lines. This suggests that 4993 has undergone a relatively recent <mml:math...
Long-duration gamma-ray bursts (GRBs) are powerful tracers of star-forming galaxies. We have defined a homogeneous subsample 69 Swift GRB-selected galaxies spanning very wide redshift range. Special attention has been devoted to making the sample optically unbiased through simple and well-defined selection criteria based on high-energy properties their positions sky. Thanks our extensive follow-up observations, this now achieved comparatively high degree completeness, thus provides legacy...
Abstract We report our identification of the optical afterglow and host galaxy short-duration gamma-ray burst sGRB 160821B. The spectroscopic redshift is z = 0.162, making it one lowest bursts (sGRBs) identified by Swift . Our intensive follow-up campaign using a range ground-based facilities as well Hubble Space Telescope , XMM-Newton shows evidence for late-time excess near-infrared emission in addition to complex afterglow. light curve at X-ray frequencies reveals narrow jet, <?CDATA...
ABSTRACT We introduce the Swift Gamma-Ray Burst Host Galaxy Legacy Survey (“SHOALS”), a multi-observatory high-redshift galaxy survey targeting largest unbiased sample of long-duration gamma-ray burst (GRB) hosts yet assembled (119 in total). describe motivations and development our selection criteria, including an assessment impact various observability metrics on success rate afterglow-based redshift measurement. briefly outline host observational program, consisting deep Spitzer /IRAC...