content_image/343034.jpg content_image/343041.jpg content_image/343042.jpg content_image/343043.jpg
where E$_{0}$ is the vacuum energy in the absence of quasiparticle excitations or zero point energy. However, this energy term is not a constant but depends upon µ$_{B}$ and T. The B ( T, µ$_{B}$ ) can be derived as follows [23]: 

where B$_{0}$ is the integration constant i.e., the value of B ( T, µ$_{B}$ ) at T = T$_{0}$ . The expression for B ( T, µ$_{B}$ ) in Eq. (11) and the forms of Eq. (8-10) give a compelling evidence that B ( T, µ$_{B}$ ) may be treated as T and µ$_{B}$ -dependent bag constant term [24]. In our calculation we take B 1 / 4 0 = 185 MeV and T$_{0}$ = 100 MeV . We have also taken µ$_{B}$ = 3 µ$_{q}$ . 

## IV. SECOND QUASIPARTICLE MODEL (QPM II) 

<img src='content_image/343034.jpg'>

The second thermodynamically consistent quasiparticle model is given by Bannur [16]. 

Bannur first figured out why there exists a thermodynamical incosistency in the quasiparticle description of Peshier et. al. The relation between pressure and grand canonical partition function can not hold good if the particles of the system have a temperature-dependent mass. 

So he used the definition of average energy and average number of particles and derived all the thermodynamical quantities from them in a consistent manner. In this model, the effective mass of the gluon is the same as given in Eq (4). However, the effective mass of the quarks involves the following relation: 

<img src='content_image/343041.jpg'>

were m$_{q}$$_{0}$ is the rest mass of the quarks. In this calculation, we have used m$_{q}$$_{0}$ = 8 MeV for two light quarks ( u,d ), and m$_{q}$$_{0}$ = 80 MeV for strange quark. In the above Eq (12) m$_{th}$ represents the thermal mass of the quarks and it can be written as [23]: 

<img src='content_image/343042.jpg'>

Taking these values for the effective masses, energy density can be derived from the grand canonical partition function in a thermodynamically consistent manner and is given as : 

<img src='content_image/343043.jpg'>

