A. P. Beardmore
A5013690309- Gamma-ray bursts and supernovae
- SAS software applications and methods
- Astronomical Observations and Instrumentation
- Astrophysical Phenomena and Observations
- Spectroscopy and Chemometric Analyses
- Astronomy and Astrophysical Research
- Pulsars and Gravitational Waves Research
- Stellar, planetary, and galactic studies
- Astrophysics and Cosmic Phenomena
- Astro and Planetary Science
- Particle Detector Development and Performance
- Geophysics and Gravity Measurements
- Adaptive optics and wavefront sensing
- X-ray Spectroscopy and Fluorescence Analysis
- High-pressure geophysics and materials
- Solar and Space Plasma Dynamics
- Particle Accelerators and Free-Electron Lasers
- Advanced X-ray Imaging Techniques
- Astrophysics and Star Formation Studies
- Microbial Metabolites in Food Biotechnology
- Medical Imaging Techniques and Applications
- Inertial Sensor and Navigation
- Mechanics and Biomechanics Studies
- CCD and CMOS Imaging Sensors
- Calibration and Measurement Techniques
University of Leicester
2015-2024
Medical Research Associates
2010
Pennsylvania State University
2005-2009
Goddard Space Flight Center
2008-2009
Brera Astronomical Observatory
2005
National Institute for Astrophysics
2005
University of Nevada, Las Vegas
2005
Istituto di Astrofisica Spaziale e Fisica cosmica di Palermo
2005
Institute for Advanced Study
2005
Marshall Space Flight Center
2005
We present a homogeneous X-ray analysis of all 318 gamma-ray bursts detected by the telescope (XRT) on Swift satellite up to 2008 July 23; this represents largest sample GRB data published date. In Sections 2–3, we detail methods which Swift-XRT team has developed produce enhanced positions, light curves, hardness ratios and spectra presented in paper. Software using these continues create such products for new GRBs observed Swift-XRT. also web-based tools allowing users any object XRT, not...
We present new observations of the early X-ray afterglows first 27 gamma-ray bursts (GRBs) well observed by Swift X-Ray Telescope (XRT). The show a canonical behavior, where light curve broadly consists three distinct power-law segments: (1) an initial very steep decay (∝t-α with 3 ≲ α1 5), followed (2) shallow (0.5 α2 1.0), and finally (3) somewhat steeper (1 α3 1.5). These segments are separated two corresponding break times, tbreak,1 500 s 103 tbreak,2 104 s. On top this many events have...
Context.Swift data are revolutionising our understanding of Gamma Ray Bursts. Since bursts fade rapidly, it is desirable to create and disseminate accurate light curves rapidly.
Prediction of the soft X-ray absorption along lines sight through our Galaxy is crucial for understanding spectra extragalactic sources, but requires a good estimate foreground column density photoelectric absorbing species. Assuming uniform elemental abundances this reduces to having total hydrogen density, N(Htot)=N(HI)+2N(H2). The atomic component, N(HI), reliably provided using mapped 21 cm radio emission estimating molecular N(H2), expected any particular direction, difficult....
Gamma-ray burst (GRB) afterglows have provided important clues to the nature of these massive explosive events, providing direct information on nearby environment and indirect central engine that powers burst. We report discovery two bright x-ray flares in GRB afterglows, including a giant flare comparable total energy itself, each peaking minutes after These strong, rapid imply engines bursts long periods activity, with strong internal shocks continuing for hundreds seconds gamma-ray...
With the first direct detection of merging black holes in 2015, era gravitational wave (GW) astrophysics began. A complete picture compact object mergers, however, requires an electromagnetic (EM) counterpart. We report ultraviolet (UV) and X-ray observations by Swift Nuclear Spectroscopic Telescope ARray (NuSTAR) EM counterpart binary neutron star merger GW170817. The bright, rapidly fading emission indicates a high mass ($\approx0.03$ solar masses) wind-driven outflow with moderate...
We report the discovery of unusually bright long-duration gamma-ray burst (GRB), GRB 221009A, as observed by Neil Gehrels Swift Observatory (Swift), Monitor All-sky X-ray Image (MAXI), and Neutron Star Interior Composition Explorer Mission (NICER). This energetic was located relatively nearby (z = 0.151), allowing for sustained observations afterglow. The large luminosity low Galactic latitude (b 4.3 degrees) make 221009A a powerful probe dust in Milky Way. Using echo tomography we map...
We present observations of the early X-ray emission for a sample 40 gamma-ray bursts (GRBs) obtained using Swift satellite which narrow-field instruments were pointed at burst within 10 minutes trigger. Using data from Burst Alert and X-Ray Telescopes, we show that light curve can be well described by an exponential relaxes into power law, often with flares superimposed. The transition time between law provides physically defined timescale duration. In most breaks to shallower decay first...
We present the catalog of sources detected in first 22 months data from hard X-ray survey (14--195 keV) conducted with BAT coded mask imager on \swift satellite. The contains 461 above 4.8 sigma level BAT. High angular resolution for every source Swift XRT or archival have allowed associations to be made known counterparts other wavelength bands over 97% detections, including discovery ~30 galaxies previously unknown as AGN and several new Galactic sources. A total 266 are associated Seyfert...
We present observations of GRB 060124, the first event for which both prompt and afterglow emission could be observed simultaneously in their entirety by three Swift instruments. Indeed, Swift-BAT triggered on a precursor ~570s before main burst peak, this allowed to repoint narrow field instruments position ~350s occurred. 060124 also Konus-Wind, harder gamma-ray band (up 2MeV). Thanks these exceptional circumstances, temporal spectral properties can studied optical, X-ray ranges. While...
The majority of short gamma-ray bursts (SGRBs) are thought to originate from the merger compact binary systems collapsing directly form a black hole. However, it has been proposed that both SGRBs and long (LGRBs) may, on rare occasions, an unstable millisecond pulsar (magnetar) prior final collapse. GRB 090515, detected by Swift satellite was extremely short, with T90 0.036 ± 0.016 s, had very low fluence 2 × 10−8 erg cm−2 faint optical afterglow. Despite this, 0.3–10 keV flux in first 200 s...
ASTROSAT is India's first astronomy satellite that will carry an array of instruments capable simultaneous observations in a broad range wavelengths: from the visible, near ultraviolet (NUV), far-UV (FUV), soft X-rays to hard X-rays. There be five principal scientific payloads aboard satellite: (i) Soft X-ray Telescope (SXT), (ii) three Large Area Xenon Proportional Counters (LAXPCs), (iii) Cadmium-Zinc-Telluride Imager (CZTI), (iv) two Ultra-Violet Imaging Telescopes (UVITs) one for visible...
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: Gamma Ray Burst models predict the broadband spectral evolution and temporal of energy flux. In contrast, standard data analysis tools repositories provide count-rate data, or use single flux conversion factors for all neglecting evolution. Aims: To produce Swift BAT XRT light curves in units, where is accounted for. Methods: We have developed software to hardness ratio information track GRBs, thus convert from instruments on into accurate, evolution-aware curves. Results: The...
We present the 1SXPS (Swift-XRT point source) catalog of 151,524 X-ray sources detected by Swift-XRT in 8 yr operation. The covers 1905 deg2 distributed approximately uniformly on sky. analyze data two ways. First we consider all observations individually, for which have a typical sensitivity ∼3 × 10−13 erg cm−2 s−1 (0.3–10 keV). Then co-add covering same location sky: these images ∼9 10−14 Our sky coverage is nearly 2.5 times that 3XMM-DR4, although factor ∼1.5 less sensitive. median...
Aims. We present a new measurement of the cosmic X-ray background (CXRB) in 1.5-7 keV energy band, performed by exploiting Swift telescope (XRT) data archive. also CXRB spectral model wider band (1.5-200 keV), obtained combining these with recently published Swift-BAT measurement.