The nature of $$Z_b$$Zb states from a combined analysis of $$\Upsilon (5S)\rightarrow h_b(mP) \pi ^+ \pi ^-$$Υ(5S)→hb(mP)π+π- and $$\Upsilon (5S)\rightarrow B^{(*)}\bar{B}^{(*)}\pi $$Υ(5S)→B(∗)B¯(∗)π

With a combined analysis of data on $$\Upsilon (5S)\rightarrow h_b(1P,2P)\pi ^+\pi ^-$$Υ(5S)→hb(1P,2P)π+π- and $$\Upsilon (5S)\rightarrow B^{(*)}\bar{B}^{(*)}\pi $$Υ(5S)→B(∗)B¯(∗)π in an effective field theory approach, we determine resonance parameters of $$Z_b$$Zb states in two scenarios. In one scenario we assume that $$Z_b$$Zb states are pure molecular states, while in the other one we assume that $$Z_b$$Zb states contain compact components. We find that the present data favor that there should be some compact components inside $$Z_b^{(\prime )}$$Zb(′) associated with the molecular components. By fitting the invariant mass spectra of $$\Upsilon (5S)\rightarrow h_b(1P,2P)\pi ^+\pi ^-$$Υ(5S)→hb(1P,2P)π+π- and $$\Upsilon (5S)\rightarrow B^{(*)}\bar{B}^{*}\pi $$Υ(5S)→B(∗)B¯∗π, we determine that the probability of finding the compact components in $$Z_b$$Zb states may be as large as about 40 %.