Search Results - "Keenan, F. P"

H α LINE PROFILE ASYMMETRIES AND THE CHROMOSPHERIC FLARE VELOCITY FIELD by Kuridze, D, Mathioudakis, M, Simoes, P J A, van der Voort, L Rouppe, Carlsson, M, Jafarzadeh, S, Allred, J C, Kowalski, A F, Kennedy, M, Fletcher, L, Graham, D, Keenan, F P

“…The asymmetries observed in the line profiles of solar flares can provide important diagnostics of the properties and dynamics of the flaring atmosphere. In…”
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Spectroscopic Inversions of the Ca ii 8542 Line in a C-class Solar Flare by Kuridze, D., Henriques, V., Mathioudakis, M., Koza, J., Zaqarashvili, T. V., Rybák, J., Hanslmeier, A., Keenan, F. P.

“…We study the C8.4-class solar flare SOL2016-05-14T11:34 UT using high-resolution spectral imaging in the Ca ii 8542 line obtained with the CRISP imaging…”
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A Si iv/O iv Electron Density Diagnostic for the Analysis of IRIS Solar Spectra by Young, P. R., Keenan, F. P., Milligan, R. O., Peter, H.

“…Solar spectra of ultraviolet bursts and flare ribbons from the Interface Region Imaging Spectrograph (IRIS) have suggested high electron densities of > 10 12…”
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Electron-impact excitation of O ii fine-structure levels by Kisielius, R., Storey, P. J., Ferland, G. J., Keenan, F. P.

“…Effective collision strengths for forbidden transitions among the five energetically lowest fine-structure levels of O ii are calculated in the Breit–Pauli…”
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KELVIN-HELMHOLTZ INSTABILITY IN SOLAR CHROMOSPHERIC JETS: THEORY AND OBSERVATION by Kuridze, D., Zaqarashvili, T. V., Henriques, V., Mathioudakis, M., Keenan, F. P., Hanslmeier, A.

“…ABSTRACT Using data obtained by the high-resolution CRisp Imaging SpectroPolarimeter instrument on the Swedish 1 m Solar Telescope, we investigate the dynamics…”
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Improved Fe ii Emission-line Models for AGNs Using New Atomic Data Sets by Sarkar, A., Ferland, G. J., Chatzikos, M., Guzmán, F., van Hoof, P. A. M., Smyth, R. T., Ramsbottom, C. A., Keenan, F. P., Ballance, C. P.

“…Abstract Understanding the Fe II emission from active galactic nuclei (AGNs) has been a grand challenge for many decades. The rewards from understanding the…”
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Transit timing variations in WASP-10b induced by stellar activity by Barros, S. C. C., Boué, G., Gibson, N. P., Pollacco, D. L., Santerne, A., Keenan, F. P., Skillen, I., Street, R. A.

“…The hot-Jupiter WASP-10b was reported by Maciejewski et al. to show transit timing variations (TTVs) with an amplitude of ∼3.5 min. These authors proposed that…”
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Towards converged electron-impact excitation calculations of low-lying transitions in Fe  ii by Smyth, R T, Ramsbottom, C A, Keenan, F P, Ferland, G J, Ballance, C P

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The WASP Project and the SuperWASP Cameras by Pollacco, D. L., Skillen, I., Cameron, A. Collier, Christian, D. J., Hellier, C., Irwin, J., Lister, T. A., Street, R. A., West, R. G., Anderson, D., Clarkson, W. I., Deeg, H., Enoch, B., Evans, A., Fitzsimmons, A., Haswell, C. A., Hodgkin, S., Horne, K., Kane, S. R., Keenan, F. P., Maxted, P. F. L., Norton, A. J., Osborne, J., Parley, N. R., Ryans, R. S. I., Smalley, B., Wheatley, P. J., Wilson, D. M.

“…The SuperWASP cameras are wide‐field imaging systems at the Observatorio del Roque de los Muchachos on the island of La Palma in the Canary Islands, and at the…”
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DEPARTURE OF HIGH-TEMPERATURE IRON LINES FROM THE EQUILIBRIUM STATE IN FLARING SOLAR PLASMAS by Kawate, T., Keenan, F. P., Jess, D. B.

“…ABSTRACT The aim of this study is to clarify if the assumption of ionization equilibrium and a Maxwellian electron energy distribution is valid in flaring…”
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OBSERVATIONS AND SIMULATIONS OF THE Na i D1 LINE PROFILES IN AN M-CLASS SOLAR FLARE by Kuridze, D., Mathioudakis, M., Christian, D. J., Kowalski, A. F., Jess, D. B., Grant, S. D. T., Kawate, T., Simões, P. J. A., Allred, J. C., Keenan, F. P.

“…ABSTRACT We study the temporal evolution of the Na i D1 line profiles in the M3.9 flare SOL2014-06-11T21:03 UT, using observations at high spectral resolution…”
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A giant outburst two years before the core-collapse of a massive star by Botticella, M. T, Pastorello, A, Nielsen, T. B, Bufano, F, Stanishev, V, Elias-Rosa, N, Mattila, S, Patat, F, Navasardyan, H, Augusteijn, T, Nakano, S, Smartt, S. J, Harutyunyan, A, Cappellaro, E, Deng, J, Keenan, F. P, Cao, C, Turatto, M, Lorenzi, V, Smoker, J. V, Agnoletto, I, Yamaoka, H, Zampieri, L, Itagaki, K, Bonnet-Bidaud, J.-M, Eldridge, J. J, Valenti, S, Mazzali, P. A, Meng, X, Xu, D, Iijima, T, Boles, T, Benetti, S, Dennefeld, M, Young, D

“…The death of massive stars produces a variety of supernovae, which are linked to the structure of the exploding stars. The detection of several precursor stars…”
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A fast hybrid algorithm for exoplanetary transit searches by Collier Cameron, A., Pollacco, D., Street, R. A., Lister, T. A., West, R. G., Wilson, D. M., Pont, F., Christian, D. J., Clarkson, W. I., Enoch, B., Evans, A., Fitzsimmons, A., Haswell, C. A., Hellier, C., Hodgkin, S. T., Horne, K., Irwin, J., Kane, S. R., Keenan, F. P., Norton, A. J., Parley, N. R., Osborne, J., Ryans, R., Skillen, I., Wheatley, P. J.

“…We present a fast and efficient hybrid algorithm for selecting exoplanetary candidates from wide-field transit surveys. Our method is based on the widely used…”
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ROSA: A High-cadence, Synchronized Multi-camera Solar Imaging System by Jess, D. B., Mathioudakis, M., Christian, D. J., Keenan, F. P., Ryans, R. S. I., Crockett, P. J.

“…The Rapid Oscillations in the Solar Atmosphere (ROSA) instrument is a synchronized, six-camera high-cadence solar imaging instrument developed by Queen’s…”
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Do All Flares Have White-Light Emission? by Jess, D. B, Mathioudakis, M, Crockett, P. J, Keenan, F. P

“…High-cadence, multiwavelength optical observations of a solar active region (NOAA AR 10969), obtained with the Swedish Solar Telescope, are presented…”
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Distance limits to intermediate- and high-velocity clouds by Smoker, J. V., Fox, A. J., Keenan, F. P.

“…We present optical spectra of 403 stars and quasi-stellar objects in order to obtain distance limits towards intermediate- and high-velocity clouds (IHVCs),…”
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Photospheric magnetic vortex structures by SHELYAG, S, FEDUN, V, KEENAN, F. P, ERDELYI, R, MATHIOUDAKIS, M

“…Using direct numerical magneto-hydrodynamic (MHD) simulations, we demonstrate the evidence of two physically different types of vortex motions in the solar…”
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The spin-orbit angles of the transiting exoplanets WASP-1b, WASP-24b, WASP-38b and HAT-P-8b from Rossiter-McLaughlin observations by Simpson, E. K., Pollacco, D., Cameron, A. Collier, Hébrard, G., Anderson, D. R., Barros, S. C. C., Boisse, I., Bouchy, F., Faedi, F., Gillon, M., Hebb, L., Keenan, F. P., Miller, G. R. M., Moutou, C., Queloz, D., Skillen, I., Sorensen, P., Stempels, H. C., Triaud, A., Watson, C. A., Wilson, P. A.

“…We present observations of the Rossiter-McLaughlin effect for the transiting exoplanets WASP-1b, WASP-24b, WASP-38b and HAT-P-8b, and deduce the orientations…”
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WASP-1b and WASP-2b: two new transiting exoplanets detected with SuperWASP and SOPHIE by Cameron, A. Collier, Bouchy, F., Hébrard, G., Maxted, P., Pollacco, D., Pont, F., Skillen, I., Smalley, B., Street, R. A., West, R. G., Wilson, D. M., Aigrain, S., Christian, D. J., Clarkson, W. I., Enoch, B., Evans, A., Fitzsimmons, A., Fleenor, M., Gillon, M., Haswell, C. A., Hebb, L., Hellier, C., Hodgkin, S. T., Horne, K., Irwin, J., Kane, S. R., Keenan, F. P., Loeillet, B., Lister, T. A., Mayor, M., Moutou, C., Norton, A. J., Osborne, J., Parley, N., Queloz, D., Ryans, R., Triaud, A. H. M. J., Udry, S., Wheatley, P. J.

“…We have detected low-amplitude radial-velocity variations in two stars, USNO-B1.0 1219–0005465 (GSC 02265–00107 = WASP–1) and USNO-B1.0 0964–0543604 (GSC…”
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High-precision transit observations of the exoplanet WASP-13b with the RISE instrument by Barros, S. C. C., Pollacco, D. L., Gibson, N. P., Keenan, F. P., Skillen, I., Steele, I. A.

“…WASP-13b is a sub-Jupiter mass exoplanet orbiting a G1V type star with a period of 4.35 d. The current uncertainty in its impact parameter (0 < b < 0.46)…”
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