Excited quarks production at FCC and SppC pp colliders

Potential discovery, observation and exclusion limits of excited u and d quarks with gamma + jet final state are researched at the multi-TeV scale colliders, FCC and SppC in this paper. Both colliders, FCC and SppC, show that excited u and d quarks could be discovered up to 42.1 TeV and 55.2 TeV for u*, 30.3 TeV and 39.4 TeV for d* and 42.3 TeV and 55.5 TeV mass values for degenerate case (m(u)* = m(d)*), respectively. The determination of the excited quarks compositeness scale is examined, which will be up to multi-PeV level. Besides these analyses, free parameters (f(s), f and f') are scanned from around 0.1 up to 1 that show excited quark could be discovered at dozens of TeV with even coupling constants under 0.1.