Study of stellar mass and concentration impact on star formation activity for void paired galaxies. (a) Central panel: Scatter plot of log(SFR/M_*) as a function of log(M_*/M_sun) for pair galaxies in the void interiors (blue), in void walls (green), and in the field (black). Diamonds and solid lines indicate the median. The vertical dotted line represents log(M_*/M_sun)=9.5. Left panel: log(SFR/M_*) normalized distribution for log(M_*/M_sun)< 9.5 paired galaxies in voids and field. Right panel: Same as in the left panel but for log(M_*/M_sun)> 9.5. (b) Analogous to panel a but for non-interacting galaxies. (c) Central panel: Scatter plot of log(SFR/M_*) as a function of C for pair galaxies in the void interiors (blue), in void walls (green), and in the field (black). Diamonds and solid lines indicate the median. The vertical dotted line represents C= 2.5. Left panel: log(SFR/M_*) normalized distribution for C <  2.5 paired galaxies in voids and field. Right panel: Same as in the left panel but for C >  2.5. (d) Analogous to panel c but for non-interacting galaxies.