The holographic dark energy model is proposed by Li as an attempt for probing the nature of dark energy within the framework of quantum gravity .
The main characteristic of holographic dark energy is governed by a numerical parameter c in the model .
The parameter c can only be determined by observations .
Thus , in order to characterize the evolving feature of dark energy and to predict the fate of the universe , it is of extraordinary importance to constrain the parameter c by using the currently available observational data .
In this paper , we derive constraints on the holographic dark energy model from the latest observational data including the gold sample of 182 Type Ia supernovae ( SNIa ) , the shift parameter of the cosmic microwave background ( CMB ) given by the three-year Wilkinson Microwave Anisotropy Probe ( WMAP ) observations , and the baryon acoustic oscillation ( BAO ) measurement from the Sloan Digital Sky Survey ( SDSS ) .
The joint analysis gives the fit results in 1- \sigma : c = 0.91 ^ { +0.26 } _ { -0.18 } and \Omega _ { m 0 } = 0.29 \pm 0.03 .
That is to say , though the possibility of c < 1 is more favored , the possibility of c > 1 can not be excluded in one-sigma error range , which is somewhat different from the result derived from previous investigations using earlier data .
So , according to the new data , the evidence for the quintom feature in the holographic dark energy model is not as strong as before .