Browsing by Author "Guenther, David B."

Browsing by Author "Guenther, David B."

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    MOST observations of the Herbig Ae [delta]-Scuti star HD 34282 
    Guenther, David B.; Casey, M. P.; Zwintz, K.; Weiss, W. W.; Amado, P. J.; Diaz-Fraile, D.; Rodriguez, E.; Kuschnig, R.; Matthews, J. M.; Moffat, A. F. J. (Royal Astronomical SocietyOxford University Press, 2013-01)
    Microvariability and Oscillations of STars observations and model analysis of the Herbig Ae star HD 34282 (V1366 Ori) reveal [delta] Scuti pulsations. 22 frequencies are observed, 10 of which confirm those previously ...

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    MOST observations of the roAp stars HD 9289, HD 99563, and HD 134214 
    Guenther, David B.; Gruberbauer, Michael; Huber, D.; Kuschnig, R.; Weiss, W. W.; Matthews, J. M.; Moffat, A. F. J.; Rowe, J. F.; Rucinski, S. M.; Sasselov, D. (EDP Sciences, 2011-06)
    We report on the analysis of high-precision space-based photometry of the roAp (rapidly oscillating Ap) stars HD 9289, HD 99563, and HD 134214. All three stars were observed by the MOST satellite for more than 25 days, ...

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    MOST photometry and DDO spectroscopy of the eclipsing (white dwarf + red dwarf) binary V471 Tau 
    Guenther, David B.; Kaminski, Krzysztof Z.; Rucinski, Slavek M.; Matthews, Jaymie M.; Kuschnig, Rainer; Rowe, Jason F.; Moffat, Anthony F. J.; Sasselov, Dimitar; Walker, Gordon A. H.; Weiss, Werner W. (American Astronomical Society, 2007-09)
    The Hyades K2 V + WD system 471 Tau is a prototype post-common envelope system and a likely cataclysmic binary progenitor. We present 10 days of nearly continuous optical photometry by the MOST (Microvariability and ...

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    MOST photometry and modeling of the rapidly oscillating (roAp) star [gamma] Equulei 
    Guenther, David B.; Gruberbauer, Michael; Saio, H.; Huber, D.; Kallinger, T.; Weiss, W. W.; Kuschnig, R.; Matthews, J. M.; Moffat, A. F. J.; Rucinski, S. (EDP Sciences, 2008)
    Aims. Despite photometry and spectroscopy of its oscillations obtained over the past 25 years, the pulsation frequency spectrum of the rapidly oscillating Ap (roAp) star [gamma] Equ has remained poorly understood. Better ...

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    MOST photometry of the roAp star 10 Aquilae 
    Guenther, David B.; Huber, D.; Saio, H.; Gruberbauer, Michael; Weiss, W. W.; Rowe, J. F.; Hareter, M.; Kallinger, T.; Reegen, P.; Matthews, J. M. (EDP Sciences, 2008-05)
    Context. We present 31.2 days of nearly continuous MOST photometry of the rapidly oscillating Ap star 10 Aql. Aims. The goal was to provide an unambiguous frequency identification for this little studied star, as well as ...

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    MOST photometry of the RRd Lyrae variable AQ Leo: two radial modes, 32 combination frequencies and beyond 
    Guenther, David B.; Gruberbauer, Michael; Kolenberg, Katrien; Rowe, Jason F.; Huber, Daniel; Matthews, Jaymie M.; Reegen, Piet; Kuschnig, Rainer; Cameron, Chris; Kallinger, T. (Oxford University Press, 2007-08)
    Highly precise and nearly uninterrupted optical photometry of the RR Lyrae star AQ Leo was obtained with the MOST (Microvariability and Oscillations of Stars) satellite over 34.4 d in 2005 February–March. AQ Leo was the ...

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    MOST space-based photometry of the transiting exoplanet system HD 189733: precise timing measurements for transits across an active star 
    Guenther, David B.; Miller-Ricci, Eliza; Rowe, Jason F.; Sasselov, Dimitar; Matthews, Jaymie M.; Kuschnig, Rainer; Croll, Bryce; Moffat, Anthony F. J.; Rucinski, Slavek M.; Walker, Gordon A. H. (American Astronomical SocietyIOP Publishing, 2008-07-20)
    We have measured transit times for HD 189733b passing in front of its bright (V = 7.67), chromospherically active, and spotted parent star. Nearly continuous broadband optical photometry of this system was obtained with ...

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    MOST space-based photometry of the transiting exoplanet system HD 209458: transit timing to search for additional planets 
    Guenther, David B.; Miller-Ricci, Eliza; Rowe, Jason F.; Sasselov, Dimitar; Matthews, Jaymie M.; Kuschnig, Rainer; Moffat, Anthony F. J.; Rucinski, Slavek M.; Walker, Gordon A. H.; Weiss, Werner W. (American Astronomical SocietyIOP Publishing, 2008-07-20)
    We report on the measurement of transit times for the HD 209458 planetary system from photometry obtained with the MOST (Microvariability and Oscillations of Stars) space telescope. Deviations from a constant orbital period ...

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    Mu Eridani from MOST and from the ground: an orbit, the SPB component’s fundamental parameters and the SPB frequencies 
    Jerzykiewicz, M.; Lehmann, H.; Niemczura, E.; Molenda- Zakowicz, J.; Dymitrov, W.; Fagas, M.; Guenther, David B.; Hartmann, M.; Hrudkova, M.; Kaminski, K.; Weiss, Werner W. (Oxford University Press, 2013-06)

    MOST time series photometry of μ Eri, an SB1 eclipsing binary with a rapidly rotating SPB primary, is reported and analysed. The analysis yields a number of sinusoidal terms, mainly due to the intrinsic ...


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    The nature of p-modes and granulation in HD 49933 observed by CoRoT 
    Guenther, David B.; Gruberbauer, Michael; Kallinger, T.; Fossati, L.; Weiss, W. W. (EDP Sciences, 2010-02)
    Context. Recent observations of HD 49933 by the space-photometric mission CoRoT provide photometric evidence of solar type oscillations in a star other than our Sun. The first published reduction, analysis, and interpretation ...

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    The nature of p-modes and granulation in Procyon: new MOST photometry and new Yale convection models 
    Guenther, David B.; Kallinger, T.; Gruberbauer, Michael; Huber, D.; Weiss, W. W.; Kuschnig, R.; Demarque, P.; Robinson, F.; Matthews, J. M.; Moffat, A. F. J. (American Astronomical Society, 2008-11)
    We present new photometry of Procyon, obtained by MOST during a 38 day run in 2007, and frequency analyses of those data. The long time coverage and low point-to-point scatter of the light curve yield an average noise ...

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    New slowly pulsating B stars in the field of the young open cluster NGC 2244 discovered by the MOST photometric satellite 
    Guenther, David B.; Gruber, D.; Saio, H.; Kuschnig, R.; Fossati, L.; Handler, G.; Zwintz, K.; Weiss, W. W.; Matthews, J. M.; Moffat, A. F. J. (Oxford University Press, 2012-02)
    During two weeks of nearly continuous optical photometry of the young open cluster NGC 2244 obtained by the Microvariability and Oscillations of STars (MOST) satellite,we discovered two new slowly pulsating B (SPB) stars, ...

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    Non-detection of previously reported transits of HD 97658b with MOST photometry 
    Dragomir, Diana; Matthews, Jaymie M.; Howard, Andrew W.; Antoci, Victoria; Henry, Gregory W.; Guenther, David B.; Johnson, John A.; Kuschnig, Rainer; Marcy, Geoffrey W.; Moffat, Anthony F. J. (American Astronomical Society, 2012-11-10)
    The radial velocity-discovered exoplanet HD 97658b was recently announced to transit, with a derived planetary radius of 2.93 ± 0.28 R⊕. As a transiting super-Earth orbiting a bright star, this planet would make an attractive ...

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    Nonradial p-modes in the G9.5 giant [epsilon] Ophiuchi? Pulsation model fits to MOST photometry 
    Kallinger, T.; Guenther, David B.; Matthews, J. M.; Weiss, W. W.; Huber, D.; Kuschnig, R.; Moffat, A. F. J.; Rucinski, S. M.; Sasselov, D. (European Southern ObservatoryEDP Sciences, 2008)
    The G9.5 giant [epsilon] Oph shows evidence of radial p-mode pulsations in both radial velocity and luminosity. We re-examine the observed frequencies in the photometry and radial velocities and find a best model fit to ...

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    Observations of Cepheids with the MOST satellite: contrast between pulsation modes 
    Evans, N. R.; Szabo, R.; Derekas, A.; Szabados, L.; Cameron, C.; Matthews, J. M.; Sasselov, D.; Kuschnig, R.; Rowe, J. F.; Guenther, David B. (Oxford University Press, 2015-02)
    The quantity and quality of satellite photometric data strings is revealing details in Cepheid variation at very low levels. Specifically, we observed a Cepheid pulsating in the fundamental mode and one pulsating in the ...

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    On the detection of Lorentzian profiles in a power spectrum: a Bayesian approach using ignorance priors 
    Guenther, David B.; Gruberbauer, Michael; Kallinger, T.; Weiss, W. W. (EDP Sciences, 2009-11)
    Aims. Deriving accurate frequencies, amplitudes, and mode lifetimes from stochastically driven pulsation is challenging, more so, if one demands that realistic error estimates be given for all model fitting parameters. As ...

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    Oscillations in the massive Wolf-Rayet star WR 123 with the MOST satellite 
    Guenther, David B.; Lefevre, L.; Marchenko, S. V.; Moffat, A. F. J.; Chene, A. N.; Smith, S. R.; St-Louis, N.; Matthews, J. M.; Kuschnig, R.; Poteet, C. A. (American Astronomical Society and IOP Publishing, 2005-11-20)
    We present the results of intensive visual-broadband photometric monitoring of the highly variable WN8 Wolf-Rayet star WR 123, obtained by the MOST (Microvariability and Oscillations of STars) satellite. This first Canadian ...

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    Photometric variability in FU Ori and Z CMa as observed by MOST 
    Siwak, Michal; Rucinski, Slavek M.; Matthews, Jaymie M.; Kuschnig, Rainer; Guenther, David B.; Moffat, Anthony F. J.; Rowe, Jason F.; Sasselov, Dimitar; Weiss, Werner W. (Oxford University Press, 2013-06)

    Photometric observations obtained by the MOST satellite were used to characterize optical small-scale variability of the young stars FU Ori and Z CMa. Wavelet analysis for FU Ori reveals the possible existence ...


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    Properties of 42 solar-type Kepler targets from the Asteroseismic Modeling Portal 
    Metcalfe, T. S.; Creevey, O. L.; Drogan, G.; Mathur, S.; Xu, H.; Bedding, T. R.; Chaplin, W. J.; Christensen-Dalsgaard, J.; Karoff, C.; Trampedach, R.; Gruberbauer, Michael; Guenther, David B. (The American Astronomical Society, 2014-10)
    Recently the number of main-sequence and subgiant stars exhibiting solar-like oscillations that are resolved into individual mode frequencies has increased dramatically. While only a few such data sets were available for ...

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    Pulsation analysis of V 588 MON AND V 589 MON observed with the MOST AND CoRoT satellites 
    Zwintz, K.; Kallinger, T.; Guenther, David B.; Gruberbauer, Michael; Kuschnig, R.; Weiss, W. W.; Auvergne, M.; Jorda, L.; Favata, F.; Matthews, J.; Fischer, M. (American Astronomical SocietyIOP Publishing, 2011-03-01)
    The two pulsating pre-main sequence (PMS) stars V 588 Mon and V 589 Mon were observed by CoRoT for 23.4 days in 2008 March during the Short Run SRa01 and in 2004 and 2006 by MOST for a total of ∼70 days. We present their ...