Results 11 to 20 of about 753 (61)

Kepler observations of A-F pre-main sequence stars in Upper Scorpius: Discovery of six new $\delta$~Scuti and one $\gamma$~Doradus stars [PDF]

, 2015
We present light curves and periodograms for 27 stars in the young Upper Scorpius association (age=$11 \pm 1$\,Myr) obtained with the Kepler spacecraft. This association is only the second stellar grouping to host several pulsating pre-main sequence (PMS)
Balona, L., Catanzaro, G., Giarrusso, M., Marconi, M., Palla, F., Ripepi, V.   +5 more
core   +2 more sources

SMEI observations of previously unseen pulsation frequencies in γ Doradus [PDF]

, 2008
Aims. As g-mode pulsators, gamma-Doradus-class stars may naïvely be expected to show a large number of modes. Taking advantage of the long photometric time-series generated by the solar mass ejection imager (SMEI) instrument, we have studied the star ...
Balona, Breger, Christensen-Dalsgaard, Dupret, Frescura, Handler, Henry, I. R. Stevens, Kaye, Kuschnig, Lenz, N. J. Tarrant, Roberts, S. A. Spreckley, Spreckley, Tarrant, Uytterhoeven, W. J. Chaplin, Y. P. Elsworth   +18 more
core   +2 more sources

Spectrum Analysis of Bright Kepler Gamma Doradus Candidate Stars [PDF]

, 2012
Ground-based spectroscopic follow-up observations of the pulsating stars observed by the Kepler satellite mission are needed for their asteroseismic modelling.
A. Tkachenko, Aerts, B. Smalley, Balona, Balona, Balona, Borucki, Bruntt, C. Aerts, Cousins, Cuypers, De Cat, Droege, Dupret, Gilliland, Gray, Grevesse, Grigahcène, Guzik, H. Lehmann, Henry, Hoeg, J. Debosscher, Kaye, Krisciunas, Kupka, Kurucz, Lehmann, Marquardt, Mathias, Monet, Munari, Paunzen, Paunzen, Rodríguez, Rowe, Sadakane, Schmidt-Kaler, Shulyak, Skrutskie, Tsymbal, Uytterhoeven, Zacharias   +42 more
core   +2 more sources

The Gamma Doradus variables, a new class of pulsating stars. The case of HD 224945

, 1996
A multisite campaign involving five observatories allowed us to solve the light curve of the Gamma Doradus star HD 224945. The multiperiodic content, the high frequency term at 3.00 c/d and the frequency spacing between the observed terms strongly support its pulsational nature.
Poretti, E., Akan, C., Bossi, M., Koen, C., Krisciunas, K., Rodriguez, E.   +5 more
openaire   +2 more sources

Variable stars in the Open Cluster M11 (NGC 6705)

, 2007
V-band time-series CCD photometric observations of the intermediate-age open cluster M11 were performed to search for variable stars. Using these time-series data, we carefully examined light variations of all stars in the observing field.
Breger M., C.‐U. Lee, Frandsen S., Frandsen S., Hoffmeister C., J.‐R. Koo, Kaluzny J., McNamara B. J., Rodriguez E., Rodriguez E., Rucinski S. M., S.‐C. Rey, S.‐L. Kim, Vilhu O., Viskum M., Y. B. Kang, Y. H. Kim, Y.‐B. Jeon   +17 more
core   +1 more source

A Search for $\gamma$ Doradus-Type Variable Stars in the Hyades

, 1995
$\gamma$ Doradus stars are photometrically variable early F-type stars on or just above the main sequence in the Hertzsprung-Russell Diagram. They vary by as much as 0.1 mag on time scales an order of magnitude slower than the fundamental radial pulsation period. These brightness variations are presumably due to non-radial gravity-mode pulsations.
Krisciunas, Kevin, Crowe, Richard A., Luedeke, Kenneth D., Roberts, Mavourneen   +3 more
openaire   +2 more sources

Variability survey of brightest stars in selected OB associations

, 2016
The stellar evolution theory of massive stars remains uncalibrated with high-precision photometric observational data mainly due to a small number of luminous stars that are monitored from space.
Eenmäe, Tõnis, Kolka, Indrek, Laur, Jaan, Leedjärv, Laurits, Tuvikene, Taavi   +4 more
core   +1 more source

Oscillations in stellar superflares [PDF]

, 2015
Two different mechanisms may act to induce quasi-periodic pulsations (QPP) in whole-disk observations of stellar flares. One mechanism may be magneto-hydromagnetic (MHD) forces and other processes acting on flare loops as seen in the Sun.
Balona, L. A., Broomhall, A. -M., Kosovichev, A., Nakariakov, V. M., Pugh, C. E., Van Doorsselaere, T.   +5 more
core   +2 more sources

The VLT-FLAMES Tarantula survey XX. The nature of the X-ray bright emission-line star VFTS 399 [PDF]

, 2015
Context. The stellar population of the 30 Doradus star-forming region in the Large Magellanic Cloud contains a subset of apparently single, rapidly rotating O-type stars.
A. J. Bird, Antoniadis, Berghoefer, Bird, Blaauw, Blay, Bonanos, Brott, C. J. Evans, Cantiello, Casares, Cheng, Cioni, Clark, Clark, Clark, Clark, Clark, Clark, Corbet, Corbet, Corcoran, Crampton, de Mink, Dougherty, Dufton, E. S. Bartlett, Eldridge, Evans, F. R. N. Schneider, Farrell, Galache, Gibson, González-Galán, Grebel, H. Sana, Haberl, Haberl, I. Soszyński, J. Maíz Apellániz, J. S. Clark, Kato, Knigge, Köhler, L. K. Townsley, Langer, Lanz, Li, Lomb, Marshall, Martins, Martins, Maíz Apellániz, Maíz Apellániz, McBride, Meixner, Mennickent, Mineo, N. Langer, N. R. Walborn, Nazé, Negueruela, Negueruela, Negueruela, Negueruela, Okazaki, P. L. Dufton, P. S. Broos, Petrovic, Pfahl, Podsiadlowski, Popov, Press, Puls, Ramírez-Agudelo, Rauw, Reig, Reig, Reig, Ribó, Riquelme, S. E. de Mink, Sabbi, Salpeter, Sana, Sana, Scargle, Schneider, Schneider, Shakura, Shtykovskiy, Skrutskie, Smith, Stella, Tarasov, Townsend, Townsley, Townsley, Udalski, Vasilopoulos, W. D. Taylor, Walborn, Walborn, Walborn, Wellstein   +104 more
core   +9 more sources

On Machine-Learned Classification of Variable Stars with Sparse and Noisy Time-Series Data

, 2011
With the coming data deluge from synoptic surveys, there is a growing need for frameworks that can quickly and automatically produce calibrated classification probabilities for newly-observed variables based on a small number of time-series measurements.
Arien Crellin-Quick, Bailey, Ball, Barning, Blockeel, Blomme, Breiman, Breiman, Burman, Butler, Cesa-Bianchi, Cheeseman, Covey, Dan L. Starr, Doering, Eyer, Eyer, Eyer, Eyer, Flores, Freund, Friedman, Hastie, Ivezić, John M. Brewer, Joseph W. Richards, Joshua S. Bloom, Justin Higgins, Knerr, LSST Science Collaborations ., Maxime Rischard, Millan-Gabet, Moffat, Nathaniel R. Butler, O'Keefe, Perryman, Press, Quinlan, Rachel Kennedy, Rebbapragada, Sesar, Stankov, Suchkov, Udalski, Vapnik, Walkowicz, Wasserman, Willemsen, Woźniak, Wu   +49 more
core   +1 more source