Temperature Dependence of Upsilon Suppression in Quark--Gluon Plasma and Study of Its Critical Parameters

Abstract

The critical values of screening parameters for Υ 1S and Υ 2S in Quark-Gluon Plasma (QGP) have been estimated, where the screened potential is represented by an optical potential of type V (r, λ) = −[ V0+iW0 1+exp((r−R)λ) ]. It has been observed that the critical screening length possesses smaller value indicating a larger suppression compared to the value obtained when the screened potential is represented by real potential. The variation of twoparticle energies of Υ 1S and Υ 2S with temperature has also been studied. It has been observed that below T = 0.8 T c , the two-particle energy remains almost invariant before approaching to deconfinement phase at T = T c. The results obtained are compared with other existing estimates.

A hidden-charm $$\varvec{S=-1}$$ S = - 1 pentaquark from the decay of $$\varvec{\varLambda _b}$$ Λ b into $$\varvec{J/\psi \, \eta \varLambda }$$ J / ψ η Λ states

“…The CERN discovery triggered a large number of theoretical works trying to give an explanation of the two reported states. The molecular picture was invoked in [11][12][13][14], the diquark picture in [15][16][17][18][19], QCD sum rules were used in [20,21], and the soliton model was employed in [22]. It has also been argued that the observed enhancement could be due to kinematical effects or triangular singularities [23][24][25].…”

QCD sum rule study of hidden-charm pentaquarks

“…Yet, this experimental observation triggered more studies to explain their nature, such as meson-baryon molecules [14][15][16][17][18][19][20], diquark-diquark-antiquark pentaquarks [21][22][23][24][25], compact diquark-triquark pentaquarks [26,27], the topological soliton model [28], genuine multiquark states other than molecules [29], kinematical effects related to the triangle singularity [30][31][32], etc. Their productions and decay properties are also interesting and have been studied in Refs.…”

Hidden-charm pentaquark state inΛb0→J/ψpπ−decay

“…Yet, the experimental observation of these states triggered more theoretical works. Various pictures have been proposed for the nature of these states, such as meson-baryon molecules [17][18][19][20][21][22][23], diquark-diquark-antiquark pentaquarks [24][25][26][27], compact diquark-triquark pentaquarks [28,29],D-soliton states [30], genuine multiquark states other than molecules [31], and kinematical effects related to the so-called triangle singularity [32][33][34] (for a more extensive summary, see Ref. [4]).…”