Are the higher dimensional fields in string theory interact via quanta or strings (like how the EM field interacts via photons)?

Question

We have many fields in higher dimensional string theory for charges (B field, C field, RK, RR). Are these fields made up of individual particles like how the EM field is made up of photons? Or do they just have no exchange particles and just carry a strength when produces by strings/ branes?

Answer 1

Those fields, fluxes, etc come from particular closed string modes. (The graviton is just one mode of the closed string.) For example see slides 48, 49 here.

Answer 2

This is a comment. I hope you get an answer by an expert in strings.

Roughly: string theory is an extension of quantum mechanics and should be consistent with quantum field theory. In QFT the fields are inactive, the photon field etc. over all space time. They are not composed by individual particles, they are a system where creation and annihilation operators generate and annihilate the named particles. I expect that this will be true in a more convoluted way with the fields defined in string theory.

Answer 3

The Ramond-Ramond field is a higher gauge field and they are sourced by D-branes which are charged under them. In this sense, they are just like the electromagnetic field which is an ordinary gauge field. To get exchange particles, that is quanta, one would quantise the superstring in a background supporting such a field.