Browsing School of Physics by Title
Now showing items 20-39 of 116
-
Discovery of VHE $\gamma$-ray emission from the SNR G54.1+0.3
(2010)We report the discovery of very high energy gamma-ray emission from the direction of the SNR G54.1+0.3 using the VERITAS ground-based gamma-ray observatory. The TeV signal has an overall significance of 6.8$\sigma$ and ... -
Electron beam therapy at extended SSD: a Monte Carlo investigation of output fom a Siemens Oncor linear accelerator
(2008)Electron-beam therapy is used to treat superficial tumors at a standard 100 cm source-to-surface distance (SSD). However, certain clinical situations require the use of an extended SSD. In the present study, Monte Carlo ... -
Evidence for long-term Gamma-ray and X-ray variability from the unidentified TeV source HESS J0632+057
(2009)HESS J0632+057 is one of only two unidentified very-high-energy gamma-ray sources which appear to be point-like within experimental resolution. It is possibly associated with the massive Be star MWC 148 and has been suggested ... -
Exceptionally bright TEV flares from the binary LS I+61 degrees 303
(IOP Publishing, 2016-01-20)The TeV binary system LS I +61 degrees 303 is known for its regular, non-thermal emission pattern that traces the orbital period of the compact object in its 26.5 day orbit around its B0 Ve star companion. The system ... -
The First VERITAS Telescope
(2006)The first atmospheric Cherenkov telescope of VERITAS (the Very Energetic Radiation Imaging Telescope Array System) has been in operation since February 2005. We present here a technical description of the instrument and a ... -
FirstNuSTAR observations of MRK 501 within a radio to TeV multi-instrument campaign
(IOP Publishing, 2015-10-10)We report on simultaneous broadband observations of the TeV-emitting blazar Markarian 501 between 2013 April 1 and August 10, including the first detailed characterization of the synchrotron peak with Swift and NuSTAR. During ... -
The Galway astronomical Stokes polarimeter: an all-Stokes optical polarimeter with ultra-high time resolution
(Springer Verlag, 2013-06-28)Many astronomical objects emit polarised light, which can give information both about their source mechanisms, and about (scattering) geometry in their source regions. To date (mostly) only the linearly polarised components ... -
Gamma-rays from the quasar PKS 1441+25: story of an escape
(2015-12-20)Outbursts from gamma-ray quasars provide insights on the relativistic jets of active galactic nuclei and constraints on the diffuse radiation fields that fill the universe. The detection of significant emission above 100 ... -
GASP - Galway Astronomical Stokes Polarimeter
(2009)The Galway Astronomical Stokes Polarimeter (GASP) is an ultra-high-speed, full Stokes, astronomical imaging polarimeter based upon a Division of Amplitude Polarimeter. It has been developed to resolve extremely rapid ... -
High Time Resolution Astrophysics in the Extremely Large Telescope Era : White Paper
(2010)High Time Resolution Astrophysics (HTRA) concerns itself with observations on short scales normally defined as being lower than the conventional read-out time of a CCD. As such it is concerned with condensed objects such ... -
A high-speed bi-polar outflow from the archetypical pulsating star Mira A
(2009)Optical images and high-dispersion spectra have been obtained of the ejected material surrounding the pulsating AGB star Mira A. The two streams of knots on either side of the star, found in far ultra-viollet (FUV) GALEX ... -
High-time Resolution Astrophysics and Pulsars
(2008)The discovery of pulsars in 1968 heralded an era where the temporal characteristics of detectors had to be reassessed. Up to this point detector integration times would normally be measured in minutes rather seconds and ... -
Highlight Talk: Recent Results from VERITAS
(2009)VERITAS is a state-of-the-art ground-based gamma-ray observatory that operates in the very high-energy (VHE) region of 100 GeV to 50 TeV. The observatory consists of an array of four 12m-diameter imaging atmospheric Cherenkov ... -
Improved simulation of small electron fields for external beam radiation therapy
(2009)This paper reports on improved simulation of small electron fields from a Siemens Primus linear accelerator. Accelerator simulation was performed using the Monte Carlo user code BEAMnrc. Source and geometry parameters ... -
In vivo correlation mapping microscopy
(Society of Photo-optical Instrumentation Engineers (SPIE), 2016-03)To facilitate regular assessment of the microcirculation in vivo, noninvasive imaging techniques such as nailfold capillaroscopy are required in clinics. Recently, a correlation mapping technique has been applied to optical ... -
An investigation into the use of MMCTP to tune accelerator source parameters and testing its clinical application.
(2013)This paper presents an alternative method to tune Monte Carlo electron beam parameters to match measured data using a minimal set of variables in order to reduce the model setup time prior to clinical implementation of the ... -
Investigation of nanoscale structural alterations of cell nucleus as an early sign of cancer
(BioMed Central, 2014)Background: The cell and tissue structural properties assessed with a conventional bright-field light microscope play a key role in cancer diagnosis, but they sometimes have limited accuracy in detecting early-stage cancers ... -
An investigation of the Eigenvalue Calibration Method (ECM) using GASP for non-imaging and imaging detectors
(Springer Verlag, 2016-02)Polarised light from astronomical targets can yield a wealth of information about their source radiation mechanisms, and about the geometry of the scattered light regions. Optical observations, of both the linear and ...