  Background: The $\beta$-delayed proton-decay of $^{13}\mathrm{O}$ has
previously been studied, but the direct observation of $\beta$-delayed
$\alpha$+$\alpha$+$\alpha$+p decay has not been reported. Purpose: Observing
rare 3$\alpha$+p events from the decay of excited states in
$^{13}\mathrm{N}^{\star}$ allows for a sensitive probe of exotic
highly-clustered configurations in $^{13}$N. Method: To measure the low-energy
products following $\beta$-delayed 3$\alpha$p-decay, the TexAT Time Projection
Chamber was employed using the one-at-a-time $\beta$-delayed charged-particle
spectroscopy technique at the Cyclotron Institute, Texas A&M University.
Results: A total of $1.9 \times 10^{5}$ $^{13}\mathrm{O}$ implantations were
made inside the TexAT Time Projection Chamber. 149 3$\alpha$+p events were
observed yielding a $\beta$-delayed 3$\alpha+p$ branching ratio of 0.078(6)%.
Conclusion: Four previously unknown $\alpha$-decaying states were observed, one
with a strong $^{9}\mathrm{B(g.s)}+\alpha$ characteristic at 11.3 MeV, one with
a $^{9}\mathrm{B}(\frac{1}{2}^{+})+\alpha$ nature at 12.4 MeV, and another two
that are dominated by $^{9}\mathrm{B}({\frac{5}{2}}^{+})+\alpha$ at 13.1 and
13.7 MeV. Population of the $\frac{1}{2}^{+}$ state in $^{9}\mathrm{B}$ has
been unambiguously seen, cementing the predicted existence of the mirror-state
based on the states observed in $^{9}\mathrm{Be}$.
