  Axion-like particles (ALPs) are hypothetical bosons which may couple with
photons. Since many ALPs can be emitted from hot and dense astrophysical
plasma, nearby supernovae (SNe) are a possible probe into their properties
including the ALP mass m_a and the coupling constant g_{ag} between ALPs and
photons. I calculated ALP emission from a type Ia SN (SN Ia) model with the
near-Chandrasekhar mass. It is found that the ALP luminosity from SNe Ia
reaches ~10^43(g_{ag}/10^-10 GeV^-1)^2 erg s^-1 if m_a < 1 MeV. Heavy ALPs
emitted from SNe are unstable and decay into photons. I predict the time delay
and the flux of decay photons that reach Earth from a nearby SN Ia. It is found
that the decay photons may provide a constraint on g_{ag} which is as stringent
as an SN 1987A limit if an SN Ia is located 1 kpc away or closer and
next-generation MeV gamma-ray satellites observe it ~1-10 years after the
explosion.
