  We use the stellar evolution code MESA to study the negative jet feedback
mechanism in common envelope jets supernovae (CEJSNe) where a neutron star (NS)
launches jets in the envelope of a red supergiant (RSG), and find that the
feedback reduces the mass accretion rate to be $\chi_{\rm j} \simeq 0.04-0.3$
times the mass accretion rate without the operation of jets. We mimic the
effect of the jets on the RSG envelope by depositing the energy that the jets
carry into the envelope zones outside the NS orbit. The energy deposition
inflates the envelope, therefore reducing the density in the NS vicinity, which
in turn reduces the mass accretion rate in a negative feedback cycle. In
calculating the above values for the negative jet feedback coefficient (the
further reduction in the accretion rate) $\chi_{\rm j}$, we adopt the canonical
ratio of jets power to actual accretion power of $0.1$, and the results of
numerical simulations that show the actual mass accretion rate to be a fraction
of $0.1-0.5$ of the Bondi-Hoyle-Lyttleton mass accretion rate.
