  The noncentrosymmetric superconductor AuBe have been investigated using the
magnetization, resistivity, specific heat, and muon-spin relaxation/rotation
measurements. AuBe crystallizes in the cubic FeSi-type B20 structure with
superconducting transition temperature observed at $T_{c}$ = 3.2 $\pm$ 0.1 K.
The low-temperature specific heat data, $C_{el}$(T), indicate a weakly-coupled
fully gapped BCS superconductivity with an isotropic energy gap
2$\Delta(0)/k_{B}T_{c}$ = 3.76, which is close to the BCS value of 3.52.
Interestingly, type-I superconductivity is inferred from the $\mu$SR
measurements, which is in contrast with the earlier reports of type-II
superconductivity in AuBe. The Ginzburg-Landau parameter is $\kappa_{GL}$ = 0.4
$<$ 1/$\sqrt{2}$. The transverse-field $\mu$SR data transformed in the maximum
entropy spectra depicting the internal magnetic field probability distribution,
P(H), also confirms the absence of the mixed state in AuBe. The thermodynamic
critical field, $H_{c}$, calculated to be around 259 Oe. The zero-field $\mu$SR
results indicate that time-reversal symmetry is preserved and supports a
spin-singlet pairing in the superconducting ground state.
