Constraints of general screened modified gravities from comprehensive
  analysis of binary pulsars
  Testing gravity by binary pulsars nowadays becomes a key issue. Screened
modified gravity is a kind of scalar-tensor theory with screening mechanism in
order to satisfy the tight Solar System tests. In this paper, we investigate
how the screening mechanism affects the orbital dynamics of binary pulsars, and
calculate in detail the five post-Keplerian (PK) parameters in this theory.
These parameters differ from those of general relativity (GR), and the
differences are quantified by the scalar charges, which lead to the dipole
radiation in this theory. We combine the observables of PK parameters for the
ten binary pulsars, respectively, to place the constraints on the scalar
charges and possible deviations from GR. The dipole radiation in the neutron
star (NS) - white dwarf (WD) binaries leads to more stringent constraints on
deviations from GR. The most constraining systems for the scalar charges of NS
and WD are PSR~B1913$+$16 and PSR~J1738$+$0333, respectively. The results of
all tests exclude significant strong-field deviations and show good agreement
with GR.
