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We have analyzed the ALMA archival data of the SO ($J_N=6_5-5_4$ and$J_N=7_6-6_5$), CO ($J=2-1$), and CCH ($N=3-2, J=7/2-5/2, F=4-3$) lines fromthe class 0 protobinary system, NGC1333 IRAS 4A. The images of SO ($J_N =6_5-5_4$) and CO ($J=2-1$) successfully separate two northern outflow lobesconnected to each protostar, IRAS 4A1 and IRAS 4A2. The outflow from IRAS 4A2shows an S-shaped morphology, consisting of a flattened envelope around IRAS4A2 with two outflow lobes connected to both edges of the envelope. Theflattened envelope surrounding IRAS 4A2 has an opposite velocity gradient tothat of the circumbinary envelope. The observed features are reproduced by themagnetohydrodynamic simulation of the collapsing core whose magnetic fielddirection is misaligned to the rotational axis. Our simulation shows that theintensity of the outflow lobes is enhanced on one side, resulting in theformation of S-shaped morphology. The S-shaped outflow can also be explained bythe precessing outflow launched from an unresolved binary with a separationlarger than 12 au (0.04arcsec). Additionally, we discovered a previouslyunknown extremely high velocity component at $\sim$45-90 km/s near IRAS 4A2with CO. CCH ($J_{N,F}=7/2_{3,4}-5/2_{2,3}$) emission shows two pairs of blobsattaching to the bottom of shell like feature, and the morphology issignificantly different from those of SO and CO lines. Toward IRAS 4A2, theS-shaped outflow shown in SO is overlapped with the edges of CCH shells, whileCCH shells have the velocity gradients opposite to the flattened structurearound IRAS 4A2.

ALMA Observations toward the S-shaped Outflow and the Envelope around NGC1333 IRAS 4A2