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We report the first asteroseismic results obtained with the Hertzsprung SONG Telescope from an extensive high-precision radial-velocity observing campaign of the subgiant muHerculis. The data set was collected during 215 nights in 2014 and…

We present time-series radial velocities of the G8 subgiant star beta Aql obtained in 2022 and 2023 using SONG-Tenerife and, for the first time, SONG-Australia. We also analyse a sector of TESS photometry that overlapped with the 2022 SONG…

We report the results of observations of p-mode oscillations in the G0 subgiant star HD 35833 in both radial velocities and photometry with NEID and TESS, respectively. We achieve separate, robust detections of the oscillation signal with…

We report observations of the G0 subgiant eta Boo made in 1998, in Balmer-line equivalent width with the 2.5-m Nordic Optical Telescope and in velocity with the 24-inch Lick CAT. In both data sets we see an excess in the power spectrum,…

We report the firm discovery of solar-like oscillations in a giant star. We monitored the star xi Hya (G7III) continuously during one month with the CORALIE spectrograph attached to the 1.2m Swiss Euler telescope. The 433 high-precision…

To explore the hypothesis that KIC 8462852's aperiodic dimming is caused by artificial megastructures in orbit (Wright et al. 2015), rather than a natural cause such as cometary fragments in a highly elliptical orbit (Marengo et al. 2015),…

Earth and Planetary Astrophysics · Physics 2016-07-06 Marlin Schuetz , Douglas A. Vakoch , Seth Shostak , Jon Richards

Aims: As g-mode pulsators, gamma-Doradus-class stars may naively 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…

Astrophysics · Physics 2009-11-13 N. J. Tarrant , W. J. Chaplin , Y. P. Elsworth , S. A. Spreckley , I. R. Stevens

Solar five-minute oscillations have been detected in the power spectra of two six-day time intervals from soft X-ray measurements of the Sun observed as a star using the Extreme Ultraviolet Spectrophotometer (ESP) onboard the Solar Dynamics…

Solar and Stellar Astrophysics · Physics 2015-06-12 Leonid Didkovsky , Alexander Kosovichev , Darrell Judge , Seth Wieman , Tom Woods

We present new U-band photometry of the magnetic Helium-strong star Sigma Ori E, obtained over 2004-2009 using the SMARTS 0.9-m telescope at Cerro Tololo Inter-American Observatory. When combined with historical measurements, these data…

Solar and Stellar Astrophysics · Physics 2015-05-18 R. H. D. Townsend , M. E. Oksala , D. H. Cohen , S. P. Owocki , A. ud-Doula

We used HARPS to measure oscillations in the low-mass star tau Cet. Although the data were compromised by instrumental noise, we have been able to extract the main features of the oscillations. We found tau Cet to oscillate with an…

We have observed oscillations in the nearby G2 subgiant star beta Hyi using high-precision velocity observations obtained over more than a week with the HARPS and UCLES spectrographs. The oscillation frequencies show a regular comb…

We present highlights and an overview of 20 FUSE and HST/STIS observations of the bright symbiotic binary EG And. The main motivation behind this work is to obtain spatially-resolved information on an evolved giant star in order to…

Astrophysics · Physics 2007-10-15 Cian Crowley , B. R. Espey , S. R. McCandliss

Based on all 2-minute cadence $TESS$ light curves from Sector 1 to 60, we provide a catalog of 8,651 solar-like oscillators, including frequency at maximum power ($\nu_{\rm max}$, with its median precision, $\sigma$=5.39\%), large frequency…

Solar and Stellar Astrophysics · Physics 2024-01-23 Jianzhao Zhou , Shaolan Bi , Jie Yu , Yaguang Li , Xianfei Zhang , Tanda Li , Liu Long , Mengjie Li , Tiancheng Sun , Lifei Ye

EF Eri is a magnetic cataclysmic variable that has been in a low accretion state for the past nine years. Low state optical spectra reveal the underlying Zeeman-split white dwarf absorption lines. These features are used to determine a…

Extrasolar planets are expected to emit detectable low frequency radio emission. In this paper we present results from new low frequency observations of two extrasolar planetary systems (Epsilon Eridani and HD 128311) taken at 150 MHz with…

Astrophysics · Physics 2009-11-13 Samuel George , Ian Stevens

We report on a search for the presence of signals from extraterrestrial intelligence in the direction of the star system KIC 8462852. Observations were made at radio frequencies between 1-10 GHz using the Allen Telescope Array. No…

Earth and Planetary Astrophysics · Physics 2018-05-08 G. R. Harp , Jon Richards , Seth Shostak , J. C. Tarter , Douglas A. Vakoch , Chris Munson

A Fourier transform analysis of 2.5 million spectra in the Sloan Digital Sky Survey was carried out to detect periodic spectral modulations. Signals having the same period were found in only 234 stars overwhelmingly in the F2 to K1 spectral…

Solar and Stellar Astrophysics · Physics 2016-10-19 E. F. Borra , E. Trottier

We present the results of a long time series of precise stellar radial velocity measurements of the planet hosting K giant star Beta Geminorum. A total of 20 hours of observations spanning three nights were obtained and the radial velocity…

Astrophysics · Physics 2009-11-13 Artie P. Hatzes , Mathias Zechmeister

GK Dra is a detached eclipsing binary system containing two early-F stars, one evolved, in an orbit with a period of 9.974 d and a small eccentricity. Its eclipsing nature was discovered using Hipparcos data, and pulsations were found in…

Solar and Stellar Astrophysics · Physics 2024-01-25 John Southworth

We report on attempts to measure the magnetic field of the pulsating B star $\nu$ Eridani with the Musicos spectropolarimeter attached to the 2m telescope at the Pic du Midi, France. This object is one of the most extensively studied stars…

Astrophysics · Physics 2009-11-11 R. S. Schnerr , E. Verdugo , H. F. Henrichs , C. Neiner