000004771 001__ 4771
000004771 005__ 20200206104901.0
000004771 037__ $$aPOSTER-2020-0058
000004771 100__ $$aVan de Steene, G. C.
000004771 245__ $$aRadial velocity variability in post-AGB stars: V448 Lac
000004771 260__ $$c2019
000004771 269__ $$c2019-12-01
000004771 520__ $$aTo investigate the binary hypothesis in the formation of planetary nebulae, we have been doing long-term photometry and radial velocity (RV) monitoring of bright post-AGB stars which possess bipolar or ellipsoidal nebulae but no indication of a disk in their spectral energy distribution, indicative of a binary companion. RV's are determined by cross correlating high-resolution spectra with a line mask. Stellar variability and companions both deform the cross correlation function (CCF) and induce periodic variations in the RV. To uniformly quantify the asymmetry of the CCF from a Gaussian, we propose to fit the CCF profile with a Gauss-Hermite series and determine all CCF parameters (RV, skewness, FWHM, and depth) in one single fit. We analyze the correlation and time series of these CCF parameters for V448 Lac and conclude that its RV variability is most likely due to stellar pulsation and not to an orbiting body.
000004771 594__ $$aNO
000004771 6531_ $$aline:profiles
000004771 6531_ $$amethods:data analysis
000004771 6531_ $$atechniques: radial velocities
000004771 6531_ $$a stars: AGB and post-AGB; individual (V448 Lac)
000004771 700__ $$aHrivnak, B. J.
000004771 700__ $$aVan Winckel, H.
000004771 773__ $$t2019,IAUS 343, 533
000004771 8560_ $$fgriet.vandesteene@observatoire.be
000004771 85642 $$ahttps://ui.adsabs.harvard.edu/abs/2019IAUS..343..533V/abstract
000004771 980__ $$aCPOSTER