  We report the synthesis and characterization of phase pure Ta3Sb, a material
predicted to be topological with eightfold degenerate fermionic states [Science
353, aaf5037 (2016)] and to exhibit a large spin Hall effect [Sci. Adv. 5,
eaav8575 (2019]. We observe superconductivity in Ta3Sb with Tc~ 0.67 K in both
electrical resistivity \r{ho}(T) and specific heat C(T) measurements. Field
dependent measurements yield the superconducting phase diagram with an upper
critical field of Hc2(0) ~ 0.95 T, corresponding to a superconducting coherence
length of {\xi} ~18.6 nm. The gap ratio deduced from specific heat anomaly,
2{\Delta}0/kBTc is 3.46, a value close to the Bardeen-Cooper-Schrieffer (BCS)
value of 3.53. From a detailed analysis of both the transport and thermodynamic
data within the Ginsburg-Landau (GL) framework, a GL parameter of \k{appa} ~90
is obtained identifying Ta3Sb as an extreme type-II superconductor. The
observation of superconductivity in an eightfold degenerate fermionic compound
with topological surface states and predicted large spin Hall conductance
positions Ta3Sb as an appealing platform to further explore exotic quantum
states in multifold degenerate systems.
