Euclid detectability of pair instability supernovae in binary population
  synthesis models consistent with merging binary black holes
  We infer the expected detection number of pair instability supernovae (PISNe)
during the operation of the Euclid space telescope, based on two binary
population models that are consistent with binary black holes (BHs) observed by
gravitational waves. The two models consider different PISN criteria depending
on the $^{12}$C$(\alpha, \gamma)^{16}$O reaction rate. The fiducial and
$3\sigma$ models adopt the standard and $3\sigma$-smaller $^{12}$C$(\alpha,
\gamma)^{16}$O reaction rate, which predicts that stars with helium core masses
$65-135 M_\odot$ and $90-180 M_\odot$ cause PISNe, respectively. Our fiducial
model predicts that Euclid detects several Type I or hydrogen-poor PISNe. For
the $3\sigma$ model, detection of $\sim 1$ Type I PISN by Euclid is expected if
the stellar mass distribution extends to $M_{\max} \sim 600 M_\odot$, but the
expected number becomes significantly smaller if $M_{\max} \sim 300 M_\odot$.
Thus, we may be able to prove or distinguish the fiducial and $3\sigma$ models
by the observed PISN rate. This will help us to constrain the origin of binary
BHs and the $^{12}$C$(\alpha, \gamma)^{16}$O reaction rate. PISN ejecta mass
estimates from light curves and spectra obtained by follow-up observations
would also be important to constrain the $^{12}$C$(\alpha, \gamma)^{16}$O
reaction rate.
