Provided is a real-time detector of a Bragg peak, comprising: an emitter configured to emit a particle beam toward a target region in a first direction, thereby creating emission of electromagnetic radiation in the target region; a first detection module comprising a stack of first scintillators and first photosensors respectively connected to the first scintillators and configured to detect the electromagnetic radiation and convert into a first signal; a second detection module comprising a stack of second scintillators and second photosensors respectively connected to the second scintillators and configured to detect the electromagnetic radiation and convert into a second signal; and a coincidence detection circuit configured to determine an end point of the particle beam with respect to the first direction based on the first signal and the second signal.