Observed line profile of the three emission components occurring in the Hα line. They appear successively during a pulsation cycle. The most intense emission was first discovered around the pulsation phase ϕ = 0.93. The second was for the first time observed in X Ari by Gillet & Crowe (1988) in the phase interval ϕ = 0.72 − 0.82. The third was detected recently by Preston (2011) in the three RR Lyrae stars: RV Oct, WY Ant and V1645 Sgr, with a maximum strength near phase ϕ = 0.30. Currently, there are no observations of X Ari around the phase 0.30. The two first emission components are blueshifted, while the last and weaker one is redshifted. The “apparitions” are classified according to the date of the discovery of the emission line.
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