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arXiv · 0801.4446

Detection of solar-like oscillations in the G5 subgiant mu-Herculis

A. Bonanno·S. Benatti·R. Claudi·S. Desidera·R. Gratton·S. Leccia·L. Paterno'
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Abstract

A clear detection of excess of power, providing a substantial evidence for solar-like oscillations in the G5 subgiant \muher{}, is presented. This star was observed over seven nights with the SARG echelle spectrograph operating with the 3.6-m Italian TNG Telescope, using an iodine absorption cell as a velocity reference. A clear excess of power centered at 1.2 mHz, with peak amplitudes of about 0.9 \ms in the amplitude spectrum is present. Fitting the asymptotic relation to the power spectrum, a mode identification for the $\ell=0,1,2,3$ modes in the frequency range $900-1600 \muHz$ is derived. The most likely value for the large separation turns out to be 56.5 \muHz, consistent with theoretical expectations. The mean amplitude per mode ($l=0,1$) at peak power results to be $0.63 \rm m s^{-1}$, almost three times larger than the solar one.

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A. Bonanno, S. Benatti, R. Claudi, S. Desidera, R. Gratton, S. Leccia, L. Paterno'. 2008-01-29. Detection of solar-like oscillations in the G5 subgiant mu-Herculis. https://doi.org/10.1086/528946

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