Planet around Alpha Persei?

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Planet around Alpha Persei?

Post by Edasich on 18th May 2012, 3:45 am

Detection of the 128 day radial velocity variations in the supergiant α Persei. Rotational modulations, pulsations, or a planet?

Aims. In order to search for and study the nature of the low-amplitude and long-periodic radial velocity (RV) variations of massive stars, we have been carrying out a precise RV survey for supergiants that lie near or inside the Cepheid instability strip. Methods. We have obtained high-resolution spectra of {\alpha} Per (F5 Ib) from November 2005 to September 2011 using the fiber-fed Bohyunsan Observatory Echelle Spectrograph (BOES) at Bohyunsan Optical Astronomy Observatory (BOAO). Results. Our measurements reveal that {\alpha} Per shows a periodic RV variation of 128 days and a semi-amplitude of 70 m/s. We find no strong correlation between RV variations and bisector velocity span (BVS), but the 128-d peak is indeed present in the BVS variations among several other significant peaks in periodogram. Conclusions. {\alpha} Per may have an exoplanet, but the combined data spanning over 20 years seem to suggest that the 128-d RV variations have not been stable on long-term scale, which is somewhat difficult to reconcile with the exoplanet explanation. We do not exclude the pulsational nature of the 128-d variations in {\alpha} Per. Although we do not find clear evidence for surface activity or rotational modulations by spots, coupled with the fact that the expected rotation period is ~ 130 days the rotational modulation seems to be the most likely cause of the RV variations. More observational data and research are needed to clearly determine the origin of RV the variations in {\alpha} Per.

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Re: Planet around Alpha Persei?

Post by Lazarus on 18th May 2012, 3:34 pm

I very much doubt it... as the authors note, the exoplanet hypothesis is the least plausible of their proposed solutions.

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Re: Planet around Alpha Persei?

Post by Sunchaser on 23rd May 2012, 8:51 pm

It would be an interesting locale for a planet...Sunburn City!!!!

-M-

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Re: Planet around Alpha Persei?

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