Zhong-Xu Zhai, Ming-Jian Zhang, Zhi-Song Zhang, Xian-Ming Liu, Tong-Jie Zhang
Compared with the plentiful researches of the Hubble parameter and the deceleration factor, the third time derivative of the scale factor $a(t)$ in the FRW cosmology, namely, the jerk parameter $j$ still remains less 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 by the use of observational Hubble parameter data (OHD) and Type Ia Supernovae (SNe) observations. We find that the perturbation of $j(z)$ favors a nearly zero value 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 and find that the newly released OHD measurement at $z=2.3$ can improve the constraint significantly, even tighter and more strict than the SNe one. Moreover, we calculate the deceleration factor and $Om(z)$ diagnostic of the jerk models, and find that the universe is indeed undergoing an accelerated expansion phase following the matter dominated one, which is in well consistent with the popular supported model by observation.
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http://arxiv.org/abs/1303.1620
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