Abstracts » Zoology and wildlife conservation

Absence of a planetary signature in the spectra of the star 51 Pegasi

Article Abstract:

Apparent variations in the radial velocity of star 51 Pegasi have been interpreted as a reflex motion caused by the presence of a nearby planet. However, high-spectral-resolution observations of the star show intrinsic shape variations in its spectral lines with about the same amplitude as that of the reported radial velocity variations. Since the proximity of a planet has no impact on the shapes of spectral lines, it is not likely that the detected variations in 51 Pegasi's radial velocity are caused by a planetary companion.

Stellar oscillations

---

Further evidence for the planet around 51 Pegasi

Article Abstract:

The view that there is a planet around the solar-type star 51 Pegasi was challenged by the observation of systematic variations in the line shapes of the star. These indicate stellar oscillations. However, it is now becoming widely accepted that the data are most consistent with a planetary companion to 51 Pegasi. It it not possible to be completely certain that this star has a planet, but this seems to be the most feasible explanation for the observed radial velocity variability.

---

A planetary companion for 51 Pegasi implied by absence of pulsations in the stellar spectra

Article Abstract:

The view that systematic variations in the Doppler shifts of absorption lines in the spectrum of the star 51 Pegasi indicate the existence of a planet around half the mass of Jupiter may after all be correct. Spectral line variation reported previously was not present in the observations from the 1997 observing season, and it therefore seems likely that the signal is not actually there. The signal seen previously was probably noise.

Some parts © 2013 Advameg, Inc.