The Tc Trend In The Zetta Reticuli System: N Spectra – N Trends.

Adibekyan, V.; Figueira, P.; Delgado Mena, E.; Sousa, S. G.; Santos, N. C.; González Hernández, J. I.; Israelian, G.
Bibliographical reference

EWASS Special Session 4 (2017): Star-planet interactions (EWASS-SS4-2017), held 26-30 June, 2017 in Prague, Czech Republic. Online at http://eas.unige.ch/EWASS2017/session.jsp?id=SS4

Advertised on:
10
2017
Number of authors
7
IAC number of authors
2
Citations
0
Refereed citations
0
Description
It is suggested that the chemical abundance trend with the condensation temperature, Tc , can be a signature of rocky planet formation or accretion. Recently, a strong Tc trend was reported in the Zetta Reticuli binary system (Saffe et al., 2016), where ζ2 Ret Ret shows a deficit of refractory elements relative to its companion (ζ1 Ret). This depletion was explained by the presence of a debris disk around ζ2 Ret. Later, Adibekyan et al. (2016b) confirmed the significance of the trend, however, casted doubts on the interpretation proposed. Using three individual highest quality spectra for each star, they found that the Tc trends depend on the individual spectra (three spectra of each star were used) used in the analaysis. In the current work we re-evaluated the presence and variability of the Tc trend in this system using a larger number of individual spectra. In total, 62 spectra of ζ2 Ret and 31 spectra of ζ1 Ret was used. Our results confirm the word of caution issued by Adibekyan et al. (2016b) that nonphysical factors can be at the root of the T c trends for the cases of individual spectra.