Do you want to publish a course? Click here

Wave functions and annihilation widths of heavy quarkonia

84   0   0.0 ( 0 )
 Publication date 2020
  fields
and research's language is English




Ask ChatGPT about the research

Within the framework of nonrelativistic quark-antiquark Cornell potential model formalism, we study the annihilation of heavy quarkonia. We determine their annihilation widths resulting into $gammagamma$, $gg$, $3gamma$, $3g$ and $gamma gg$ and compare our findings with the available theoretical results and experimental data. We also provide the charge radii and absolute square of radial Schrodinger wave function at zero quark-antiquark separation.



rate research

Read More

We calculate the annihilation decay rates of the $^3D_2(2^{--})$ and $^3D_3(3^{--})$ charmonia and bottomonia by using the instantaneous Bethe-Salpeter method. The wave functions of states with quantum numbers $J^{PC}=2^{--}$ and $3^{--}$ are constructed. By solving the corresponding instantaneous Bethe-Salpeter equations, we obtain the mass spectra and wave functions of the quarkonia. The annihilation amplitude is written within Mandelstam formalism and the relativistic corrections are taken into account properly. This is important, especially for high excited states, since their relativistic corrections are large. The results for the $3g$ channel are as follows: $Gamma_{^3D_2(cbar c)rightarrow ggg} = 9.24$ keV, $Gamma_{^3D_3(cbar c)rightarrow ggg}=25.0$ keV, $Gamma_{^3D_2(bbar b)rightarrow ggg}= 1.87$ keV, and $Gamma_{^3D_3(bbar b)rightarrow ggg}= 0.815$ keV.
In the paper, we derive the next-to-leading order (NLO) fragmentation function for a heavy quark, either charm or bottom, into a heavy quarkonium $J/Psi$ or $Upsilon$. The ultra-violet divergences in the real corrections are removed through the operator renormalization, which is performed under the modified minimal subtraction scheme. We then obtain the NLO fragmentation function at an initial factorization scale, e.g. $mu_{F}=3 m_c$ for $cto J/Psi$ and $mu_{F}=3m_b$ for $bto Upsilon$, which can be evolved to any scale via the use of Dokshitzer-Gribov-Lipatov-Altarelli-Parisi equation. As an initial application of those fragmentation functions, we study the $J/Psi$ ($Upsilon$) production at a high luminosity $e^+e^-$ collider which runs at the energy around the $Z$ pole and could be a suitable platform for testing the fragmentation function.
We investigate the reaction gamma+p -> V+p, with V denoting a Phi or a J/Psi meson, within the scope of perturbative QCD, treating the proton as a quark-diquark system. Our predictions extrapolate the existing forward differential cross-section data into the few-GeV momentum-transfer region. In case of the J/Psi reasonable results are only obtained by properly taking into account its mass in the perturbative calculation of the hard-scattering amplitude.
At the chiral restoration/deconfinement transition, most hadrons undergo a Mott transition from being bound states in the confined phase to resonances in the deconfined phase. We investigate the consequences of this qualitative change in the hadron spectrum on final state interactions of charmonium in hot and dense matter, and show that the Mott effect for D-mesons leads to a critical enhancement of the J/$psi$ dissociation rate. Anomalous J/psi suppression in the NA50 experiment is discussed as well as the role of the Mott effect for the heavy flavor kinetics in future experiments at the LHC. The status of our calculations of heavy quarkonium dissociation cross sections due to quark and gluon impact is reviewed, and estimates for in-medium effects due to the lowering of the ionisation threshold are given.
In this work, we revise the conventional description of J/Psi(1S), Y(1S), Psi(2S) and Y(2S) elastic photo- and electroproduction off a nucleon target within the color dipole picture and carefully study various sources of theoretical uncertainties in calculations of the corresponding electroproduction cross sections. For this purpose, we test the corresponding predictions using a bulk of available dipole cross section parametrisations obtained from deep inelastic scattering data at HERA. Specifically, we provide the detailed analysis of the energy and hard-scale dependencies of quarkonia yields employing the comprehensive treatment of the quarkonia wave functions in the Schroedinger equation based approach for a set of available c-bar{c} and b-bar{b} interquark interaction potentials. Besides, we quantify the effect of Melosh spin rotation, the Q^2-dependence of the diffractive slope and an uncertainty due to charm and bottom quark mass variations.
comments
Fetching comments Fetching comments
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا