High-velocity features in Type Ia supernova spectra provide a way to probe the outer layers of these explosions. The maximum-light spectra of the unique Type Ia supernova 2000cx exhibit interesting Ca II features with high-velocity components. The infrared triplet absorption is quadruply notched, while the II and K absorption is wide and flat. Stimulated by a three-dimensional interpretation of similar Ca II features in another Type Ia supernova (SN 2001 el; Kasen et al), we present alternative spherically symmetric and three-dimensional ejecta models to fit the high-velocity (v > 16, 000 km s~(-1)) Ca II features of SN 2000cx. We also present simple estimates of the high-velocity ejecta mass for a few trial compositions and discuss their implications for explosion modeling.
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