* Astronomy

Title: Three red giants with substellar-mass companions
Author: A. Niedzielski, A. Wolszczan, G. Nowak, M. Adamów, K. Kowalik, G. Maciejewski, B. Deka-Szymankiewicz, M. Adamczyk

We present three giant stars from the ongoing Penn State-Toru\'n Planet Search with the Hobby-Eberly Telescope, which exhibit radial velocity variations that point to a presence of planetary --mass companions around them. BD+49 828 is a M=1.52±0.22 M_{\odot} K0 giant with a msini=1.6^{+0.4}_{-0.2} MJ minimum mass companion in a=4.2^{+0.32}_{-0.2} AU (2590^{+300}_{-180}), e=0.35^{+0.24}_{-0.10} orbit. HD 95127, a logL/L_{\odot}=2.28±0.38, R=20±9 R_{\odot}, M=1.20±0.22 M_{\odot} K0 giant has a msini=5.01^{+0.61}_{-0.44} MJ minimum mass companion in a=1.28^{+0.01}_{-0.01} AU (482^{+5}_{-5}d), e=0.11^{+0.15}_{-0.06} orbit. Finally, HD 216536, is a M=1.36±0.38 M_{\odot} K0 giant with a m sin i=1.47^{+0.20}_{-0.12} MJ minimum mass companion in a=0.609^{+0.002}_{-0.002} AU (148.6^{+0.7}_{-0.7}d), e=0.38^{+0.12}_{-0.10} orbit. Both, HD 95127 b and HD 216536 b in their compact orbits, are very close to the engulfment zone and hence prone to ingestion in the near future. BD+49 828 b is among the longest period planets detected with the radial velocity technique until now and it will remain unaffected by stellar evolution up to a very late stage of its host. We discuss general properties of planetary systems around evolved stars and planet survivability using existing data on exoplanets in more detail.

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