Europlanet Research Infrastructure: Planetary Simulation Facilities (2008)
Davies, G. R., Mason, N. J., Green, S., Gómez, F., Prieto, O., Helbert, J., ...
The Europlanet Research Infrastructure consortium funded under FP7 aims to provide the EU Planetary Science community greater access for to research infrastructure. A series of networking and...
Skalny, J. D., Matejcik, S., Orszagh, J., Vladoiu, R., Mason, N. J.
Ozone generation in both positive and negative corona discharges DC corona, both operated in glow regime, feed by dry CO2 has been studied. Higher ozone concentrations were observed in negative...
The spectroscopy and chemical dynamics of microparticles explored using an ultrasonic trap (2008)
Mason, N. J., Dawes, A, Drage, E. A., Webb, S. M., McPheat, R, Hayes, G
Microsized particles play an important role in many diverse areas of science and technology, for example, surface reactions of micron-sized particles play a key role in astrochemistry, plasma...
Desorption of hot molecules from photon irradiated interstellar ices (2007)
Thrower, J. D., Burke, D. J., Collings, M. P., Dawes, A., Holtom, P. J., Jamme, F., ...
We present experimental measurements of photodesorption from ices of astrophysical relevance. Layers of benzene and water ice were irradiated with a laser tuned to an electronic transition in the...
The ultraviolet spectrum of condensed methylamine at 25 K (2007)
Holtom, P. D., Dawes, A., Davis, M. P., Hoffmann, S. V., Mukerji, R. J., Mason, N. J.
Using a monochromated synchrotron light source we have recorded the VUV spectrum of a film of solid methylamine, CH3NH2, from 6 to 10 eV. The solid-phase spectrum differs substantially from the...
VUV spectroscopy of water under cellular conditions (2007)
Mota, R., Parafita, R., Maneira, M. J. P., Mason, N. J., Garcia, G., Ribeiro, P. A., ...
The understanding of radiation damage within cells, and thence mutagenesis, depends upon a detailed knowledge of the spectroscopy and dissociation dynamics of water. Results of a new study of the...
Dissociative electron attachment to ozone at very low energies revisited (2007)
Cicman, P., Skalny, J. D., Mason, N. J.
The formation of O− and O2− following electron impact to O3 in the energy range between 0 and 3 eV is revisited using a newly designed trochoidal electron monochromator. The previous observation...
High resolution VUV photoabsorption cross section of dimethyl sulphoxide (CH3)2SO (2007)
Drage, E. A., Cahillane, P., Hoffman, S. V., Mason, N. J., Limao-Vieira, P.
The high resolution VUV photoabsorption spectrum of dimethyl sulphoxide is reported in the wavelength range 115–340 nm (10.8–3.7 eV). The result is compared with previous electron energy loss...
VUV spectroscopy of CH3Cl and CH3I (2007)
Eden, S., Limao-Vieira, P., Hoffmann, S. V., Mason, N. J.
High-resolution photoabsorption spectra of CH3Cl and CH3I are reported in the energy range 3.9–10.8 eV (320–115 nm). Several features are observed for the first time in the CH3Cl spectrum and a...
Electron stimulated desorption of H− ions from condensed acetic acid (2007)
Bertin, M., Caceres, D., Lafosse, A., Azria, R., Davis, M. P., Mason, N. J., ...
The interaction between low energy electrons and condensed acetic acid has been investigated considering H− and D− ions Electron Stimulated Desorption from the three isotopic forms CD3COOD,...
N. J. Mason, A A. Dawes, R. Mcpheat B, G. Hayes B
Microsized particles play an important role in many diverse areas of science and technology, for example, surface reactions of micron-sized particles play a key role in astrochemistry, plasma...
Probing Radiation Damage at the Molecular Level (2006)
Mason, N. J., Smialek, M. A., Moore, S. A., Folkard, M., Hoffmann, S. V.
Radiation damage of DNA and other cellular components has traditionally been attributed to ionisation via direct impact of high-energy quanta or by complex radical chemistry. However recent research...
Motch, C., Giuliani, A., Delwiche, J., Limao-Vieira, P., Mason, N.J., Hoffmann, S.V., ...
The VUV photo-absorption spectrum of hexafluorobenzene, C6F6, recorded using the synchrotron radiation in the 4–10.75 eV photon range exhibits broad bands between 4 and 8 eV, and fine features...
Electron interaction cross sections for CF3I, C2F4 and CFx(x=1-3) radicals (2006)
Rozum, I., Limao-Viera, P., Eden, S., Tennyson, J., Mason, N.J.
The supply of absolute electron-impact cross sections for molecular targets and radicals is extremely important for developing plasma reactors and testing different types of etching gases. Current...
VUV photoabsorption spectroscopy of sulfur dioxide ice (2006)
Holtom, P.D., Dawes, A., Mukerji, R.J., Davis, M.P., Webb, S.M., Hoffman, S.V., ...
In this paper we present the first study of the VUV photoabsorption spectrum of condensed phase SO2 recorded over the VUV region 120 to 320 nm (10.33 to 3.64 eV). Distinct spectral features were...
Current-driven breakdown of the quantized Hall states of a broken-gap 2D electron-hole system (2006)
Takashina, K., Nicholas, R. J., Kardynal, B., Mason, N. J., Maude, D. K., Portal, J. C.
We report results from experimental studies on the current driven breakdown of the quantum Hall effect in an InAs/GaSb-based electron-hole system. We find that the critical currents observed in this...
Fragmentation of transient water anions following low-energy electron capture by H2O/D2O (2006)
Fedor, J., Cicman, P., Coupier, B., Feil, S., Winkler, M., Gluch, K., ...
Dissociative electron attachment (DEA) to water in the gaseous phase has been studied using two different crossed electron–molecule beam apparatus. Ion yields for the formation of the three...
Limao-Vieira, P., Vasekova, Eva, Raja Sekhar, B. N., Mason, N. J., Hoffmann, S. V.
High resolution VUV photoabsorption spectra of 1,1-difluoroethene (C2H2F2) and difluorochloromethane (CF2HCl) are reported in the wavelength range 115–200 nm (10.8–6.2 eV). New photoabsorption...
Modelling electron interactions: a semi-rigorous method (2006)
Vinodkumar, M., Joshipura, K. N., Mason, N. J.
We report total electron scattering cross sections (TCS) for SF6, SF5 CF3, and CF3I, molecules of interest to the plasma industry over the energy range from threshold to 2000 eV. We also report the...
VUV SPECTROSCOPY OF WATER UNDER CELLULAR CONDITIONS (2006)
Mota, R., Parafita, R., Maneira, M. J. P., Mason, N. J., Garcia, G., Ribeiro, P. A., ...
The understanding of radiation damage within cells, and thence mutagenesis, depends upon a detailed knowledge of the spectroscopy and dissociation dynamics of water. Results of a new study of the...
Atmospheric chemistry with synchrotron radiation (2005)
Mason, N.J., Dawes, A., Mukerji, R., Drage, E.A., Vasekova, E., Webb, S.M., ...
Synchrotron radiation is a good mimic of solar radiation and therefore has been widely used to study photo-induced physics and chemistry in the terrestrial atmosphere. In this paper we review how...
Electron and photon impact studies of CF[subscript 3]I (2005)
Eden, S., Limao Vieira, P., Mason, N.J.
Book description: Topics that are covered include electron scattering in the scanning TEM; basic theory of inelastic electron imaging; study of confined atoms by electron excitation; helium bubbles...
Electron energy loss spectroscopy of trifluromethyl sulphur pentaflouride (2005)
Book description: Topics that are covered include electron scattering in the scanning TEM; basic theory of inelastic electron imaging; study of confined atoms by electron excitation; helium bubbles...
Laboratory studies of astrophysical molecules: a new UCL apparatus (2005)
Dawes, A., Mason, N.J., Tegeder, P., Holtom, P.
Topics that are covered include electron scattering in the scanning TEM; basic theory of inelastic electron imaging; study of confined atoms by electron excitation; helium bubbles created in extreme...
Electron driven process: scientific challenges and technological opportunities (2005)
Book description: Topics that are covered include electron scattering in the scanning TEM; basic theory of inelastic electron imaging; study of confined atoms by electron excitation; helium bubbles...
High-resolution, temperature dependant, Fourier transform infrared spectroscopy of CF3I (2005)
Webb, S M, Mayr, D, McPheat, R A, Drage, E, Vasekova, E, Mason, N J, ...
CF3I is being considered as a replacement for some of the global warming gases currently used in the plasma industry, however before this compound can be put into wide-scale use the possible...
Electron interactions with CH3C00H in condensed phase (2005)
Bertin, M., Caceres, D., Lafosse, A., Azria, R., Davis, M.P., Mason, N.J., ...
R-matrix calculation of low-energy electron collisions with LiH (2004)
Antony, B.K., Joshipura, K.N., Mason, N.J., Tennyson, J.
Calculations are performed for electron scattering from LiH. These show that use of a close-coupled expansion gives results significantly different from calculations performed at the static exchange...
Limão-Vieira, P., Eden, S., Kendall, P. A., Mason, N. J., Giuliani, A., Heinesch, J., ...
A comprehensive study of the spectroscopy of trifluoromethyl sulphur pentafluoride, SF5CF3 is reported. A high resolution VUV photo-absorption spectrum of SF5CF3, has been measured using synchrotron...
Electronic excitation of tetrafluoroethylene, C2F4 (2004)
Eden, S., Limao-Vieira, P., Kendall, P.A., Mason, N.J., Delwiche, J., ...
The VUV photoabsorption spectrum of tetrafluoroethylene is reported in the wavelength range; 115–320 nm (10.8–3.9 eV). The result is compared with high-energy electron energy loss spectra (EELS)....
Electronic excitation of tetrafluoroethylene, C2F4 (2004)
Eden, S., Limão-Vieira, P., Kendall, P. A., Mason, N. J., Delwiche, J., ...
The VUV photoabsorption spectrum of tetrafluoroethylene is reported in the wavelength range; 115–320 nm (10.8–3.9 eV). The result is compared with high-energy electron energy loss spectra (EELS)....
Mikoviny, T., Kocan, M., Matejcik, S., Mason, N.J., Skalny, J.D.
The products of a negative corona discharge in both pure CO2 and mixtures of CO2 + O2 have been studied using a coaxial cylindrical electrode geometry with particular emphasis on the production of...
Investigating reflectance properties of vegetation in the mid infrared region (2004)
Drage, E A, Mason, N J, Knight, R J, McPheat, R A, Smith, K M, Williams, R G
The Infrared Reflectance of vegetation has been studied using Fourier transform infrared spectroscopy in the mid and far infrared regions. The reflectance of the leaves of two common garden plants,...
Low energy electron attachment to CH3CN (2003)
Sailer, W., Pelc, A., Limão-Vieira, P., Mason, N.J., Limtrakul, J., Scheier, P., ...
Low energy electron attachment cross sections for acetonitrile (CH3CN) are reported in the energy range from about 0 up to 10 eV determined with an energy resolution of 140 meV. Electron attachment...
Far-infrared modulated photoluminescence spectroscopy of InSb/GaSb quantum dot structures (2003)
Child, R. A., Nicholas, R. J., Mason, N. J., Shields, P. A., Wells, J-P. R., Bradley, I. V., ...
The first far-infrared modulated photoluminescence (FIRM-PL) measurements in InSb/GaSb quantum dots have been performed. Far-infrared absorption is found to both enhance and suppress the quantum dot...
Giuliani, A., Walker, I.C., Delwiche, J., Hoffmann, S.V., Limao-Viera, P., Mason, N.J., ...
The photoelectron spectrum of 2-furanmethanol (furfuryl alcohol) has been measured for ionization energies between 8 and 11.2 eV and the first three ionization bands assigned to π3,π2, and no...
Limão-Vieira, P., Eden, S., Mason, N.J.
Photo-absorption cross sections have been measured for methyl iodide, CF3I (310 nm>λ>110 nm) and dichlorodifluoromethane, CCl2F2 (225 nm>λ>110 nm) using synchrotron radiation. Electron energy loss...
Electron and photon induced processes in SF5CF3 (2003)
Limão-Vieira, P., Kendall, P.A., Eden, S., Mason, N.J., Heinesch, J., Hubin-Franskin, M-J., ...
The photo-absorption cross section of trifluoromethyl sulphur pentafluoride, SF5CF3 has been measured using synchrotron radiation in the range of 4–11 eV (310nm>λ>110 nm) and comparison made with...
Giuliani, A., Delwiche, J., Hoffmann, S.V., Limão-Vieira, P., Mason, N.J.
The vacuum ultraviolet absorption spectrum of 2-methyl furan has been recorded between 5 eV (248 nm) and 9.91 eV (125 nm) and absolute photoabsorption cross sections measured. The electronic excited...
Williart, A., Kendall, P.A., Blanco, F., Tegeder, P., García, G., Mason, N.J.
In this study, the stopping power for electrons in O2 and O3 molecules is reported for incident energies ranging from 300 to 5000 eV. The present results have been obtained by combining the...
Joshipura, K.N., Vinodkumar, M., Antony, B.K., Mason, N.J.
Total ionization cross-sections of electron impact are calculated for the molecular targets CHx, CFx, SiHx, SiFx (x = 1-4) and CCl4 at incident energies 20-3 000 eV. The calculation is based on...
Electron attachment to simple organic acids (2003)
Pelc, A., Sailer, W., Scheier, P., Mason, N.J., Illenberger, E., Märk, T.D.
Low energy (from 0 up to 13 eV) electron attachment to formic and acetic acid is studied for the first time by means of mass spectrometric detection of the product anions. The energy spread of...
Kendall, P.A., Mason, N.J., Buchanan, G.A., Marston, G., Tegeder, P., Dawes, A., ...
Absolute infrared photoabsorption cross-sections have been measured over the range 600–1500 cm−1 for the powerful greenhouse gas SF5CF3 at high resolution (0.03 cm−1) and at temperatures...
VUV and low energy electron impact study of electronic state spectroscopy of CF3I (2003)
Mason, N.J., Limão Vieira, P., Eden, S., Kendall, P., Pathak, S., Dawes, A., ...
The electronic states of CF3I have been investigated using photon and electron energy loss spectroscopy from 4 to 20 eV (310 nm>λ>60 nm). Assignments have been suggested for each of the observed...
Electron collisions with the CF radicals using the R-matrix method (2003)
Rozum, I., Mason, N.J., Tennyson, J.
The R-matrix method is used to treat electron collisions with the diatomic radical CF as a function of internuclear separation, R. These calculations concentrate on obtaining low-energy (< 10 eV)...
Electron collisions with the CF3 radical using the R-matrix method (2003)
Rozum, I., Mason, N.J., Tennyson, J.
Fluorocarbons are the main species used in etching plasmas and their properties are driven by CFx (x = 1–3) radicals. Previous calculations on CF and CF2 show low-lying resonances which may lead to...
Electron collisions with the CF radicals using the R-matrix method (2003)
Rozum, I., Mason, N.J., Tennyson, J.
The R-matrix method is used to treat electron collisions with the diatomic radical CF as a function of internuclear separation, R. These calculations concentrate on obtaining low-energy (< 10 eV)...
Monitoring Epiready Semiconductor Wafers (2003)
Allwood, D. A., Cox, S., Mason, N. J., Palmer, R., Young, R.
Gallium Arsenide (GaAs) wafers are often sold by the manufacturer as epiready', meaning the substrates can be used with no further treatment. However, there is no clear agreement on what epiready...
Insulating states of a broken-gap two-dimensional electron-hole system (2003)
Takashina, K., Nicholas, R. J., Kardynal, B., Mason, N. J., Maude, D. K., Portal, J. C.
Quantum Hall and insulating states of a 2-D electron-hole system (2003)
Takashina, K., Nicholas, R. J., Mason, N. J., Maude, D. K., Portal, J. C.
Breakdown of the QHE in an electron-hole system (2003)
Takashina, K., Nicholas, R. J., Kardynal, B., Mason, N. J., Maude, D. K., Portal, J. C.
Metallic and insulating states of a broken-gap 2-D electron-hole system (2003)
Takashina, K., Nicholas, R. J., Kardynal, B., Mason, N. J., Maude, D. K., Portal, J. C.
High resolution VUV photo-absorption cross-section for dimethylsulphide, (CH3)2S (2002)
Limão-Vieira, P., Eden, S., Kendall, P.A., Mason, N.J., Hoffmann, S.V.
The photo-absorption spectrum of (CH3)2S has been measured using synchrotron radiation in the range 5.0–11 eV (250>λ>110 nm). Electronic state assignments have been suggested for each of the...
VUV photo-absorption cross-section for CCl2F2 (2002)
Limão Viera, P., Eden, S., Kendall, P.A., Mason, N.J., Hoffmann, S.V.
The photo-absorption spectrum of CCl2F2 has been measured using synchrotron radiation in the range 5.5–11 eV (225>λ>110 nm). Electronic state assignments have been suggested for each of the...
Low energy electron attachment to formic acid (2002)
Pelc, A., Sailer, W., Scheier, P., Mason, N.J., Märk, T.D.
Using a high resolution electron energy monochromator low energy electron attachment to formic acid is studied for the first time by means of mass spectrometric detection of the product anions. The...
Low-energy electron impact elastic and inelastic scattering from CF3I (2002)
Kitajima, M., Okamoto, M., Sunohara, K., Tanaka, H., Cho, H., Samukawa, S., ...
Absolute differential cross sections for elastic scattering from CF3I are reported between 1.5 and 60 eV and over scattering angles of 20°–130°. Vibrational excitation cross sections for the...
Hubin-Franskin, M-J., Delwiche, J., Giuliani, A., Ska, M-P., Motte-Tollet, F., Walker, I.C., ...
High resolution UV-VUV photon absorption spectra of methylamine and ethylamine have been recorded between 5.0-9.0 eV (250-140 nm) using synchrotron radiation. In methylamine, the energies of the...
Electron collisions with the CF2 radical using the R-matrix method (2002)
Rozum, I., Mason, N.J., Tennyson, J.
The R-matrix method is used to treat electron collisions with the molecular radical CF2. These calculations concentrate on obtaining low-energy (less than 10 eV) elastic and excitation cross sections...
Ionization energy studies for Cl2O monomers and dimers (2002)
Hanel, G., Fedor, J., Gstir, B., Probst, M., Scheier, P., Mrk, T.D., ...
Electron ionization cross sections measured close to threshold are reported for the Cl2O monomer and dimer using a high resolution electron impact apparatus. Besides measuring the appearance energies...
Ionization energy studies for ozone and OClO monomers and dimers. (2002)
Probst, M., Hermansson, K., Urban, J., Mach, P., Muigg, D., Denifl, G., ...
Electron impact ionization cross sections measured close to threshold are reported for both the monomers and dimers of ozone and OC1O using a new high resolution electron impact apparatus. The...
Low energy electron attachment to SF5CF3 (2002)
Sailer, W., Drexel, H., Pelc, A., Grill, V., Mason, N.J., Illenberger, Eugen, ...
Low energy electron attachment to the potent greenhouse gas SF5CF3 is studied at high energy resolution by means of mass spectrometric detection of the product anions. A large dissociative electron...
Experimental investigations and modelling studies of ozone producing corona discharges (2002)
Mason, N.J., Skalny, J.D., Hadj-Ziane, S.
The ozone generation by negative corona discharge in coaxial cylindrical system of electrodes have been studied experimentally in Ar+O2 and N2+O2 mixtures. Both in argon and nitrogen mixtures with...
Electron impact ionization studies for SF5CF3 (2002)
Gstir, B., Hanel, G., Fedor, J., Probst, M., Scheier, P., Mason, N.J., ...
Electron impact ionization cross sections measured close to threshold are reported for the newly discovered greenhouse gas SF5CF3. No stable parent ion is detected but several cations are detected...
Pablos, J.L.d, Kendall, P.A., Tegeder, P., Williart, A., Blanco, F., Garca, G., ...
Total cross sections for electron scattering from O3molecules in the energy range 350-5000 eV have been measured for the first time. The experimental method used was based on the measurement of the...
Electron collisions with the CF2 radical using the R-matrix method (2002)
Rozum, I., Mason, N.J., Tennyson, J.
The R-matrix method is used to treat electron collisions with the molecular radical CF2. These calculations concentrate on obtaining low-energy (less than 10 eV) elastic and excitation cross sections...
Petchsingh, C., Nicholas, R. J., Takashina, K., Mason, N. J., Zeman, J.
We report a study of cyclotron resonance (CR) in a bilayer- bipolar InAs/GaSb structure and the influence of the spatial separation between the electrons and holes. At low magnetic fields we find...
Electron collisions with OClO using the R-matrix method (2001)
Baluja, K.L., Mason, N.J., Morgan, L.A., Tennyson, J.
The R-matrix method is used to calculate elastic and excitation cross sections of four low-lying electronic states of the OClO molecule, designated as the X 2B1, 1 2A1, 1 2B2 and 1 2A2states. Eight...
Electron collisions with OClO using the R-matrix method (2001)
Baluja, K.L., Mason, N.J., Morgan, L.A., Tennyson, J.
The R-matrix method is used to calculate elastic and excitation cross sections of four low-lying electronic states of the OClO molecule, designated as the X 2B1, 1 2A1, 1 2B2 and 1 2A2 states. Eight...
Electron energy loss spectroscopy (EELS) has been used to study the photo-absorption spectrum of trifluoromethyl sulphur pentafluoride (SF5CF3) for the first time. Comparison is made with the EELS...
Roberts, M., Chung, Y. C., Lyapin, S., Mason, N. J., Nicholas, R. J., Klipstein, P. C.
We have measured the current-voltage (I-V) of type II InAs/GaSb/InAs double heterojunctions (DHETs) with 'GaAs like' interface bonding and GaSb thickness between 0-1200 \AA. A negative differential...
VUV optical absorption and energy loss spectroscopy of chlorine nitrate (2001)
Mason, N.J., Jones, N.C., Kaminski, L., Osborne, B.A., Marston, G., Fernandez, M.A., ...
The electronic spectroscopy of the stratospheric compound chlorine nitrate (ClONO2) has been probed using photoabsorption, photoelectron, and electron energy loss spectroscopy. Spectral assignments...
Dissociative electron attachment to hydrogen (2001)
Drexel, H., Senn, G., Fiegele, T., Scheier, P., Stamatovic, A., Mason, N.J., ...
Using two different crossed-beams high-resolution electron attachment instruments (employing either a trochoidal electron monochromator or a hemispherical electron monochromator) we have determined...
Breakdown of the quantum Hall effect in an electron-hole system (2001)
Takashina, K., Nicholas, R. J., Kardynal, B., Mason, N. J., Maude, D. K., Portal, J. C.
Edge effects in an insulating state of an electron-hole system in magnetic field (2001)
Takashina, K., Nicholas, R. J., Kardynal, B., Mason, N. J., Maude, D. K., Portal, J. C.
Insulating states of a 2-dimensional electron-hole system in high magnetic field (2001)
Takashina, K., Nicholas, R. J., Kardynal, B., Mason, N. J., Maude, D. K., Portal, J. C.
A digital quantum Hall effect (2000)
Nicholas, R. J., Lakrimi, M., Kardynal, B., Khym, S., Mason, N. J., Rehman, J., ...
Cyclotron resonance in an asymmetric electron-hole InAs/GaSb DHET structure (2000)
Petchsingh, C., Nicholas, R. J., Poulter, A. J. L., Hales, V. J., Mason, N. J., Walker, P. J.
Metal-insulator oscillations in a two-dimensional electron-hole system (2000)
Nicholas, R. J., Takashina, K., Lakrimi, M., Kardynal, B., Khym, S., Mason, N. J., ...
Metal-Insulator oscillations in a Two-dimensional Electron-Hole system (1999)
Nicholas, R. J., Takashina, K., Lakrimi, M., Kardynal, B., Khym, S., Mason, N. J., ...
The electrical transport properties of a bipolar InAs/GaSb system have been studied in magnetic field. The resistivity oscillates between insulating and metallic behaviour while the quantum Hall...
Magnetic breakdown in the semimetallic InAs/GaSb system. (1998)
Symons, D. M., Lakrimi, M., Nicholas, R. J., Maude, D. K., Portal, J. C., Mason, N. J., ...