The alpha particles that are produced have a high kinetic energy, this high kinetic energy will translate to a high temperature, in fact the sun has a very high temperature in the core of 10 to 15 million kelvin. $^1$ These very hot bodies will emit black body radiation which is light and do not directly produce photons as for example an laser. The sun is basically a very hot light bulb. The wavelength and intensity that a black body emits is determined by it's temperature according to the Planck's law: $$B_\nu(\nu, T) = \frac{ 2 h \nu^3}{c^2} \frac{1}{e^\frac{h\nu}{k_\mathrm B T} - 1}.$$ Further reading

The alpha particles that are produced have a high kinetic energy, this high kinetic energy will translate to a high temperature, in fact the sun has a very high temperature in the core of 10 to 15 million kelvin. $^1$ These very hot bodies will emit black body radiation which is light and do not directly produce photons as for example an laser. The sun is basically a very hot light bulb. The wavelength and intensity that a black body emits is determined by it's temperature according to the Planck's law: $$B_\nu(\nu, T) = \frac{ 2 h \nu^3}{c^2} \frac{1}{e^\frac{h\nu}{k_\mathrm B T} - 1}.$$ Further reading