Reconstruction and constraining of the jerk parameter from OHD and SNe
  Ia observations
  Compared with the plentiful researches of the Hubble parameter and
deceleration factor, the third time derivative of the scale factor $a(t)$ in
the FRW cosmology, namely, the jerk parameter $j$ still lacks attention. In
order to study the properties of $j$, we propose several kinds of
parameterizations of $j(z)$ as a function of the redshift $z$. By setting the
standard $\Lambda$CDM model as the fiducial model, we constrain the jerk models
with the observational Hubble parameter data (OHD) and Type Ia Supernovae (SNe)
observations. We find that the perturbation of $j(z)$ favors a value of nearly
zero and the $\Lambda$CDM is well accommodated by the jerk reconstruction. We
also compare the powers of OHD and SNe in constraining the jerk models in
detail, and find that the newly released OHD measurement at $z=2.3$ can improve
the constraint significantly, even tighter than the SNe one. Furthermore, we
analyze the jerk models by calculating the Hubble parameter, equation of state,
the deceleration factor and $Om(z)$ diagnostic. Our results show that the
universe is indeed undergoing an accelerated expansion phase following the
matter-dominated one, which is consistent with the standard model by
observations.
