J. Greiner
A5015282171- Gamma-ray bursts and supernovae
- Astrophysical Phenomena and Observations
- SAS software applications and methods
- Astronomical Observations and Instrumentation
- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astrophysics and Cosmic Phenomena
- Pulsars and Gravitational Waves Research
- Astro and Planetary Science
- Particle Detector Development and Performance
- Galaxies: Formation, Evolution, Phenomena
- Nuclear Physics and Applications
- Astrophysics and Star Formation Studies
- High-pressure geophysics and materials
- Solar and Space Plasma Dynamics
- Mechanics and Biomechanics Studies
- Radio Astronomy Observations and Technology
- Advanced X-ray and CT Imaging
- Particle Accelerators and Free-Electron Lasers
- Retinoids in leukemia and cellular processes
- Protein Degradation and Inhibitors
- Geophysics and Gravity Measurements
- Dark Matter and Cosmic Phenomena
- interferon and immune responses
- Radiation Detection and Scintillator Technologies
Max Planck Institute for Extraterrestrial Physics
2016-2025
National Centre for Nuclear Research
2023
Chinese Academy of Sciences
2023
University of Geneva
2023
Max Planck Society
2009-2019
Excellence Cluster Universe
2009-2019
Technical University of Munich
2009-2019
Instituto de Astrofísica de Andalucía
2001-2018
University of Leicester
2018
University of Southampton
2017
The Swift mission, scheduled for launch in 2004, is a multiwavelength observatory gamma-ray burst (GRB) astronomy. It first-of-its-kind autonomous rapid-slewing satellite transient astronomy and pioneers the way future rapid-reaction missions. will be far more powerful than any previous GRB observing 100 bursts yr-1 performing detailed X-ray UV/optical afterglow observations spanning timescales from 1 minute to several days after burst. objectives are (1) determine origin of GRBs, (2)...
The Gamma-Ray Burst Monitor (GBM) will significantly augment the science return from Fermi Observatory in study of gamma-ray bursts (GRBs). primary objective GBM is to extend energy range over which are observed downward Large Area Telescope (LAT) on into hard X-ray where extensive previous data sets exist. A secondary compute burst locations onboard allow re-orienting spacecraft so that LAT can observe delayed emission bright bursts. uses an array 12 sodium iodide scintillators and two...
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) are highly energetic explosions signaling the death of massive stars in distant galaxies. The Burst Monitor and Large Area Telescope onboard Fermi Observatory together record GRBs over a broad energy range spanning about 7 decades gammaray energy. In September 2008, observed exceptionally luminous GRB 080916C, with largest apparent release yet measured. high-energy gamma rays to start later persist longer than lower photons. A simple spectral form fits entire...
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...
We report on the observation of bright, long gamma-ray burst, GRB 090902B, by Gamma-ray Burst Monitor (GBM) and Large Area Telescope (LAT) instruments on-board Fermi observatory. This was one brightest GRBs to have been observed LAT, which detected several hundred photons during prompt phase. With a redshift z = 1.822, this burst is among most luminous Fermi. Time-resolved spectral analysis reveals significant power-law component in LAT data that distinct from usual Band model emission seen...
Spinning up an extragalactic neutron star Ultraluminous x-ray sources (ULXs) are strange objects in other galaxies that cannot be explained by conventional accretion onto stellar-mass objects. This has led to exotic interpretations, such as the long-sought intermediate-mass black holes. Israel et al. observed a ULX nearby galaxy NGC 5907 and found it is instead star. The spinning accreting material so fast its spin period quickly accelerating. only way can consume enough explain these...
We report the discovery by Swift hard X-ray monitor of transient source J2058.4+0516 (Sw J2058+05). Our multi-wavelength follow-up campaign uncovered a long-lived (duration ≳ months), luminous (LX, iso ≈ 3 × 1047 erg s−1) and radio (νLν, 1042 counterpart. The associated optical emission, however, from which we measure redshift 1.1853, is relatively faint, this not due to large amount dust extinction in host galaxy. Based on numerous similarities with recently discovered GRB 110328A/Swift...
It is well accepted that unabsorbed as absorbed active galactic nuclei (AGNs) are needed to explain the nature and shape of Cosmic X-ray background (CXB), even if fraction highly objects (dubbed Compton-thick sources) still substantially escapes detection. We derive analyze absorption distribution using a complete sample AGNs detected by Swift–BAT in first three years survey. The represents only 4.6% total AGN population Swift–BAT. However, we show once corrected for bias against detection...
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.
NGC 7793 P13 is a variable (luminosity range ~100) ultraluminous X-ray source (ULX) proposed to host stellar-mass black hole of less than 15 M$_{\odot}$ in binary system with orbital period 64 d and 18-23 B9Ia companion. Within the EXTraS project we discovered pulsations at ~0.42 s two XMM-Newton observations P13, during which was detected $L_{\mathrm{X}}\sim2.1\times10^{39}$ $5\times10^{39}$ erg s$^{-1}$ (0.3-10 keV band). These findings unambiguously demonstrate that compact object neutron...
Fast radio bursts (FRBs) are one of the most tantalizing mysteries sky; their progenitors and origins remain unknown until now no rapid multiwavelength follow-up an FRB has been possible. New instrumentation decreased time between observation discovery from years to seconds, enables polarimetry be performed on FRBs for first time. We have discovered (FRB 140514) in real-time 14 May, 2014 at 17:14:11.06 UTC Parkes telescope triggered other wavelengths within hours event. 140514 was found with...
Abstract Quasars are galaxies hosting accreting supermassive black holes; due to their brightness, they unique probes of the early universe. To date, only a few quasars have been reported at <?CDATA $z\gt 6.5$?> (<800 Myr after big bang). In this work, we present six additional $z\gtrsim discovered using Pan-STARRS1 survey. We use sample 15 perform homogeneous and comprehensive analysis highest-redshift quasar population. report four main results: (1) majority show large blueshifts broad...
The light emitted by stars and accreting compact objects through the history of Universe is encoded in intensity extragalactic background (EBL). Knowledge EBL important to understand nature star formation galaxy evolution, but direct measurements are lim- ited Galactic other foreground emissions. Here we report an absorption feature seen combined spectra a sample gamma-ray blazars out redshift z$\sim$1.6. This caused attenuation gamma rays at optical UV frequencies, allowed us measure flux...
Observations of GRB 100724B with the Fermi Gamma-Ray Burst Monitor find that spectrum is dominated by typical Band functional form, which usually taken to represent a non-thermal emission component, but also includes statistically highly significant thermal spectral contribution. The simultaneous observation and components allows us confidently identify two components. fact these seem vary independently favors idea component photospheric origin while dominant occurs at larger radii. Our...
Since its launch in 2008, the Fermi Gamma-ray Burst Monitor (GBM) has triggered and located on average approximately two gamma-ray bursts (GRB) every three days. Here we present third of a series catalogs GRBs detected by GBM, extending second catalog more years, through middle July 2014. The resulting list includes 1405 triggers identified as GRBs. intention GBM GRB is to provide information community most important observables For each location main characteristics prompt emission,...
In this catalog we present the updated set of spectral analyses GRBs detected by Fermi Gamma-Ray Burst Monitor (GBM) during its first four years operation. It contains two types spectra, time-integrated fits and at brightest time bin, from 943 triggered GRBs. Four different models were fitted to data, resulting in a compendium more than 7500 spectra. The analysis was performed similarly, but not identically Goldstein et al. 2012. All 487 have been re-fitted using same methodology as that 456...