ρ meson unpolarized generalized parton distributions with a light-front constituent quark model

Abstract

We study ρ meson unpolarized generalized parton distributions based on a light-front constituent quark model where the quark-antiquark-meson vertex is constructed under the symmetric loop momentum convention. The form factors and some other low-energy observables of the ρ meson are calculated. Moreover, the contributions to the form factors and generalized parton distributions from the valence and nonvalence regimes are discussed and analyzed in detail. In the forward limit, the usual structure functions are estimated as well. In addition, by evolving the moments of the obtained structure functions to the scale of the lattice calculation, we give the factorization scale of our quark model. It is found that the present phenomenological model is reasonable to describe the general properties of ρ meson.

Magnetic moment of the ρ meson in instant-form relativistic quantum mechanics

“…First, we refer to different formulation of RQM in the frame of relativistic composite model (see, e.g., [42][43][44][45][46][47][48][49][50]. These approaches are the most close in spirit to our approach.…”

“…[74][75][76][77]). [42] 2.26 Melo, LF RHD [43] 2.14 Bakker, LF RHD [44] 2.1 Jaus, LF RHD [45] 1.83 Choi, LF RHD [46] 1.92 He, LF, IF RHD [47] 1.5 He, PF RHD [47] 0.9 Biernat, PF RHD [48] 2.20 Sun, LCCCM [49] 2.06 Hawes, DSE [51] 2.69 Ivanov, DSE [52] 2.44 Bhagwat, DSE [53] 2.01 Roberts, DSE [54] 2.11 Pitschmann, DSE [55] 2.11 Carrillo-Serrano, NJL [56] 2.59 Luan, NJL [57] 2.1 Samsonov, QCD sum rules [58] 2.0 ± 0.3 Aliev, QCD sum rules [59] 2.4 ± 0.4 Melikhov, LF triangle [60] 2.35 Simonis, bag model [61] 2.06 Bagdasaryan, relativistic CQM [62] 2.3 Badalian, RH [63] 1.96 Djukanovic, EFT [64] 2.24 Andersen, Latt. [65] 2.25 ± 0.34 Hedditch, Latt.…”

Polynomiality sum rules for generalized parton distributions of spin-1 targets

“…A complete picture of polynomiality for spin-1 targets is desirable due to an emerging interest in the partonic structure of particular spin-1 targets, and hard exclusive reactions involving such targets. Generalized parton distributions of the deuteron [26][27][28][29][30][31][32][33][34][35], rho meson [36][37][38][39], phi meson [19], and photon [40][41][42] have been the subjects of theoretical studies. Deeply virtual Compton scattering from the deuteron has been performed at HERMES [43,44], and is a topic of interest at Jefferson Lab [45,46], as well as the proposed Electron Ion Collider [47].…”

Quadrupole moments of the ρ meson and the S -wave deuteron and some general constraints on quadrupole moments of spin-1 systems

“…So, it is clear that the theory of such properties based on different nonperturbative approaches is in the focus of investigations for years. Let us mention for example different forms of Dirac relativistic dynamics [1][2][3][4][5][6][7][8][9][10][11][12], approaches based on the Dyson-Schwinger equation [13][14][15][16], the Nambu-Jona-Lasinio model [17,18], QCD sum rules [19,20], the light front diagram technique [21], lattice calculations [22][23][24][25]. The quadrupole moment of two-particle spin one systems with total electric charge equal to unity with S-state of the relative motion of constituents is of particular interest because the existence of the quadrupole form factor and the quadrupole moment in such systems is a purely relativistic effect.…”