A5111471820- Stellar, planetary, and galactic studies
- Astrophysics and Star Formation Studies
- Astronomy and Astrophysical Research
- Analytical Chemistry and Sensors
- Astro and Planetary Science
- TiO2 Photocatalysis and Solar Cells
- Gamma-ray bursts and supernovae
- Water Quality Monitoring and Analysis
- Astrophysical Phenomena and Observations
- Photochemistry and Electron Transfer Studies
- Astronomical Observations and Instrumentation
- Electrochemical sensors and biosensors
- Adaptive optics and wavefront sensing
- Inertial Sensor and Navigation
- Photochromic and Fluorescence Chemistry
- Free Radicals and Antioxidants
- Electrochemical Analysis and Applications
- History and Developments in Astronomy
- Advanced Sensor and Energy Harvesting Materials
- Radical Photochemical Reactions
- Geological and Geophysical Studies
- Cosmology and Gravitation Theories
- Gas Sensing Nanomaterials and Sensors
- Advanced Chemical Sensor Technologies
- Conducting polymers and applications
University of Leicester
2010-2017
Queens University
2016
Queen's University Belfast
2011-2016
California Institute of Technology
2010
University of Warwick
2010
International Union of Pure and Applied Chemistry
2009-2010
The Next Generation Transit Survey (NGTS) is a new ground-based sky survey designed to find transiting Neptunes and super-Earths. By covering at least sixteen times the area of Kepler we will small planets around stars that are sufficiently bright for radial velocity confirmation, mass determination atmospheric characterisation. NGTS instrument consist an array twelve independently pointed 20cm telescopes fitted with red-sensitive CCD cameras. It be constructed ESO Paranal Observatory,...
We present time-series photometry of 30 isolated magnetic white dwarfs, surveyed with the Jacobus Kapteyn Telescope between 2002 August and 2003 May. find that 9 were untestable due to varying comparison stars, but remaining 21, 5 (24%) are variable reliably derived periods, while a further (43%) seen vary during our study, we unable derive period. interpret variability be result rotation objects. no correlation period mass, temperature, field, or age. have found in targets low field...
The preparation and characterisation of a novel, water-proof, irreversible, reusable, UV-activated, O2 sensitive, smart plastic film is described. A pigment, consisting redox dye, methylene blue (MB), sacrificial electron donor, DL-threitol, coated onto an inorganic support with semiconductor functionality, TiO2, has been extruded in low-density polyethylene (LDPE). blue-coloured indicator readily photobleached <90 s using UVA light (4 mWcm−2), whereby MB converted to its colourless, leuco...
WD0137−349 is a white dwarf–brown dwarf binary system in 116 min orbit. We present radial velocity observations and multiwaveband photometry from V, R I the optical, to J, H Ks near-IR [3.6], [4.5], [5.8] [8.0] μm mid-IR. The light curves show variability all wavebands, with amplitude peaking at [4.5] μm, where also brightest. Fluxes brightness temperatures were computed for heated unheated atmosphere of brown (WD0137−349B) using synthetic spectra model simulations. that flux dayside...
We have spectroscopically confirmed a brown dwarf mass companion to the hydrogen atmosphere white NLTT 5306. The dwarf's atmospheric parameters were measured using Sloan Digital Sky Survey and X-shooter spectroscopy as Teff = 7756 ± 35 K log(g) 7.68 0.08, giving for primary of MWD 0.44 0.04 M⊙ at distance 71 4 pc with cooling age 710 50 Myr. existence secondary was through near-infrared arm data spectral type dL4–dL7 estimated standard indices. Combined radial velocity measurements from...
We present the prototype telescope for Next Generation Transit Survey, which was built in UK 2008/2009 and tested on La Palma Canary Islands 2010. The goals system were severalfold: to determine level of systematic noise an NGTS-like system; demonstrate that we can perform photometry at (sub) millimagnitude transit timescales across a wide-field; show it is possible detect transiting super-Earth Neptune-sized exoplanets prove technical feasibility proposed planet survey. around 100 nights...
A surprisingly large fraction (70 per cent) of hot, carbon-dominated atmosphere (DQ) white dwarfs are magnetic and/or photometrically variable on short time-scales up to ∼1000 s. However, here, we show that the hot DQ dwarf SDSS J000555.90−100213.5 is by 11 cent a longer time-scale, with period 2.110 ± 0.045 d. We find no evidence target fluctuating at an amplitude ≲±0.5 cent. Short have been interpreted as non-radial pulsators, but in case J0005−1002, it more likely variability due rotation...
There is a striking and unexplained dearth of brown dwarf companions in close orbits (< 3AU) around stars more massive than the Sun, stark contrast to frequency stellar planetary companions. Although rare relatively short-lived, these systems leave detectable evolutionary end points form white - binaries remnants can offer unique insights into births deaths their parent systems. We present discovery (orbital separation ~ 0.006 AU) substellar companion member Praesepe star cluster. Using...
The use of an acid violet 7 (AV7) smart ink to assess the activity photocatalytic paint is demonstrated. A linear correlation established between change in oxidized dye concentration, as measured by diffuse reflectance, and green component RGB color values, obtained using a portable hand-held scanner, suggesting that such tests can be monitored easily inexpensive piece office equipment, opposed expensive lab-based instrument, reflectance UV/vis spectrophotometer. bleaching AV7 follows first...
Abstract The Next Generation Transit Survey (NGTS) is a new ground-based survey for transiting exoplanets. Our primary goal to find the first statistically-significant sample of Neptunes and super-Earths that are bright enough radial velocity confirmation. By measuring precise masses radii we will constrain bulk composition internal structure planets span transition between gas giants terrestrial planets. brightest exoplanets also be suitable atmospheric characterisation with large...
The novel time-temperature indicator label comprises an ammonia sensitive layer film pressed onto a second film, comprising ammonia-generating, adhesive layer. When separated the blue-coloured reverts back to its original (ammonia free) yellow form at controllable, temperature dependant rate. labels are easily made and stored.
This is the product of a Gaia GREAT workshop on "Gaia and end states stellar evolution" held at University Leicester in April 2011.
We present a spectroscopic component analysis of 18 candidate young, wide, non-magnetic, double-degenerate binaries identified from search the Sloan Digital Sky Survey Data Release 7 (DR7). All but two pairings are likely to be physical systems. show SDSS J084952.47+471247.7 + J084952.87+471249.4 wide DA+DB binary, only second date. Combining our measurements for components 16 new with results three similar, previously known systems within DR7, we have constructed mass distribution largest...
Abstract We present an analysis of the newly resolved components two hot, double-degenerate systems, SDSS J074853.07+302543.5 + J074852.95+302543.4 and J150813.24+394504.9 J150813.31+394505.6 (CBS 229). confirm that each system has widely separated (a &gt; 100 au) consisting a H-rich, non-magnetic white dwarf high-field magnetic (HFMWD). The masses degenerates are found to be larger than typical field dwarfs. use these estimate total ages binaries demonstrate both dwarfs progeny stars...
GD1400AB was one of the first known white dwarf$+$brown dwarf binaries, and is only these systems where a ZZ Ceti pulsator. Here we present both radial velocity measurements time series photometry, analysing pulsations effects irradiation on brown dwarf. We find brightness temperatures 1760$/pm$10 K for night side 1860$/pm$10 day indicate hotter than spectra have previously suggested, although calculated using larger radius are consistent with determined spectral types. also discuss likely...
We have observed the post common envelope binary WD0137-349 in near infrared $J$, $H$ and $K$ bands determined that photometry varies on system period (116 min). The amplitude of variability increases with increasing wavelength, indicating brown dwarf is likely being irradiated by its 16500 K white companion. effect (primarily) UV irradiation atmosphere unknown, but it possible stratospheric hazes are formed. It also (an L-T transition object) itself variable due to patchy cloud cover. Both...