Very recently the NICER collaboration has published the first-ever accurate measurement of mass and radius together for \objectname PSR J0030+0451 , a nearby isolated quickly-rotating neutron star ( NS ) .
In this work we set the joint constraints on the equation of state ( EoS ) and some bulk properties of NSs with the data of \objectname PSR J0030+0451 , GW170817 and some nuclear experiments .
The piecewise polytropic expansion method and the spectral decomposition method have been adopted to parameterize the EoS .
The resulting constraints are consistent with each other .
Assuming the maximal gravitational mass of non-rotating NS M _ { TOV } lies between 2.04 M _ { \odot } and 2.4 M _ { \odot } , with the piecewise method the pressure at twice nuclear saturation density is measured to be 3.38 ^ { +2.43 } _ { -1.50 } \times 10 ^ { 34 } ~ { } { dyn~ { } cm ^ { -2 } } at the 90 \% level .
For a NS with canonical mass of 1.4 M _ { \odot } , we have the moment of inertia I _ { 1.4 } = { 1.43 } ^ { +0.28 } _ { -0.13 } \times 10 ^ { 38 } ~ { } { kg \cdot m ^ { 2 } } , tidal deformability \Lambda _ { 1.4 } = 390 _ { -140 } ^ { +320 } , radius R _ { 1.4 } = 12.2 _ { -0.9 } ^ { +1.0 } ~ { } { km } , and binding energy BE _ { 1.4 } = { 0.16 } ^ { +0.01 } _ { -0.02 } M _ { \odot } at the 90 \% level , which are improved in comparison to the constraints with the sole data of GW170817 .