In this paper, we investigate the medium modifications of pTβ
dispersion(pTβD) of inclusive jets with small radius (R=0.2) in Pb+Pb
collisions at sβ=2.76~TeV. The partonic spectrum in the initial hard
scattering of elementary collisions are obtained by an event generator
POWHEG+PYTHIA, which matches the next-to-leading (NLO) matrix elements with
parton showering, and energy loss of fast parton traversing in hot/dense QCD
medium is calculated by Monte Carlo simulation within Higher-Twist formalism of
jet quenching in heavy-ion collisions. We present the model calculations of
normalized pTβD distributions for inclusive jets in p+p and Pb+Pb
collisions at sβ=2.76~TeV, which give nice descriptions of ALICE
measurements. It is shown that the pTβD distributions of inclusive jets in
Pb+Pb are shifted to higher pTβD region relative to that in p+p. Thus the
nuclear modification factor of pTβD distributions for inclusive jets is
smaller than unity at small pTβD region, while larger than one at large
pTβD region. This behaviour results from more uneven pTβ of jet
constituents as well as the fraction alteration of gluon/quark initiated jets
in heavy-ion collisions. The difference of pTβD distributions between
groomed and ungroomed jets in Pb+Pb collisions are also discussed