Vertical component of the SDO/HMI vector magnetic field (panels (a)–(f)) showing the evolution of the photospheric magnetic field underlying the fishbone-like structure. HMI continuum intensity image (panel (g)), Hinode/SOT G-band image (panel (h)), and NVST TiO image (panel (i)) present the evolution of the sunspots. The red (blue) arrows in panels (b) and (f) are the horizontal magnetic field vectors, and in panel (d) are the tangential velocity vectors, which originate from negative (positive) longitudinal fields. The tangential velocity vectors are inferred from the DAVE4VM technique and averaged from 16:12 to 18:12 UT on 2015 March 11. In panels (a) and (c), red arrows trace an emerging dipole. The cyan dashed box indicates the FOV of the inserted image. The letters “P,” “p,” “N1,” and “N2” have the same meaning as in Figure 1(a); “N” and “n” denote the sunspots with negative polarity. The white arrow in panel (h) points to a small pore, corresponding to the negative polarity of the emerging dipole. An animation of the vertical component of the SDO/HMI vector magnetic field and the continuum intensity image is available. The animation spans from 00:00 UT on 2015 March 11 to 06:12 UT on 2015 March 12 with a 5 s cadence.

(An animation of this figure is available in the online article.)

(An animation of this figure is available.)

The video/animation of this figure is available in the online journal.