With the recent LHCb data on $\eta_c$ production and based heavy quark spin symmetry, we obtain long-distance matrix elements for both $J/\psi$ productions, among which, color-singlet one is obtained directly by fit of experiment first time. Using our elements, can provide good description hadroproduction measurements. Our predictions polarization are in agreement with pass through two sets CDF measurements medium $p_t$ region. Considering all possible uncertainties carefully, quite narrow...

In the present paper, we make a detailed study on doubly heavy baryon photoproduction in future e + − International Linear Collider (ILC). The baryons Ξ cc , bc and bb are produced via channel $$ \gamma \to {\Xi}_{QQ\prime }+\overline{Q}^{\prime }+\overline{Q} where Q Q′ stand for c or b quark, respectively. As QQ ′-baryon production, it shall first generate (QQ′)[n]-diquark then form final fragmentation, [n] stands color- spin- configurations (QQ′)-diquark states. According to...

We present the first study of QCD corrections to color-singlet (CS) $J/\psi$ production in deeply inelastic $ep$ scattering at HERA. The $K$-factor ranges from $0.85$ $2.38$ kinematic regions we study. In low transverse momentum regions, $K$-factors is even smaller, and close 1, which indicates good convergence perturbative expansion. With corrections, CS cross section still below data. At least next-to-leading order, color-octet mechanism necessary describe

We predict the rate for exclusive double-charmonium production in electron-positron annihilation $e^+ e^- \to J/\psi+\eta_c$ using perturbative quantum chromodynamics and NRQCD framework hard, heavy-quarkonium processes. The cross sections measured at $B$-factories Belle Babar $\sqrt{s}=10.6$ GeV disagree with pQCD leading-order predictions by an order of magnitude. next-to-leading are, however, very sensitive to choice renormalization scale, resulting apparent discrepancy between...

As indicated in our previous paper (Phys.Rev.D96.034002), the existing literatures studying $J/\psi$ production deeply inelastic scattering (DIS) collinear factorization are on basis of a formalism that will lead to wrong results when ranges transverse momentum or rapidity laboratory frame do not cover all values possible for them. In this paper, we present renewed DIS at HERA within nonrelativistic QCD framework leading order (LO). Three different sets long-distance matrix elements employed...

A thorough study reveals that the only key parameter for $\psi$ ($J/\psi$, $\psi'$) polarization is ratio $\langle O^\psi(^3S_1^{[8]})\rangle/\langle O^\psi(^3P_0^{[8]})\rangle$, if velocity scaling rule holds. The fit of yield data incapable determination this parameter. We provide a universal approach to fixing long-distance matrix elements (LDMEs) $J/\psi$ and $\psi'$ production. Further, with existing data, we implement approach, obtain favorable set LDMEs, manage reconcile charmonia...

We study the photoproduction of heavy quarkonium at future International Linear Collider (ILC) within nonrelativistic QCD theory. focus on production channel via subprocess $\gamma\gamma \to |[Q\bar{Q'}]_{\bf 1}(n)>+Q'+\bar{Q}$, where $Q$ and $Q'$ stand for $c$- or $b$-quark, respectively. $|[Q\bar{Q'}]_{\bf 1}(n)>$ stands color-singlet $S$-wave quarkonium, i.e., $\eta_{c}(|[c\bar{c}]_{\bf 1}(^1S_0)>)$, $J/\psi(|[c\bar{c}]_{\bf 1}(^3S_1)>)$, $B_{c}(|[c\bar{b}]_{\bf $B^*_{c}(|[c\bar{b}]_{\bf...

In our previous work [ , Phys. Rev. D 88, 074021 (2013)], it has been found that sizable charmonium events can be produced via the channel ${\mathit{e}}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{\ensuremath{\gamma}}^{*}/{Z}^{0}\ensuremath{\rightarrow}H(|c\overline{c}⟩)+\ensuremath{\gamma}$ at suggested super $Z$ factory, where $H(|c\overline{c}⟩)$ represents dominant color-singlet $S$-wave and $P$-wave states $J/\ensuremath{\psi}$, ${\ensuremath{\eta}}_{c}$, ${h}_{c}$...

We make a comparative and comprehensive study on the charmonium-exclusive productions at ${e}^{+}{e}^{\ensuremath{-}}$ collider with collision energy either round ${Z}^{0}$-boson mass for super $Z$ factory or equal to 10.6 GeV $B$ factories as Belle BABAR. total cross sections charmonium production via exclusive processes ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{\ensuremath{\gamma}}^{*}/{Z}^{0}\ensuremath{\rightarrow}{H}_{1}+{H}_{2}$...

We present a compact form of the leptonic currents for computation processes involving an initial virtual boson (photon, ${W}^{\ifmmode\pm\else\textpm\fi{}}$, or ${Z}_{0}$). For deeply inelastic scattering, once azimuthal angle plane expanded by initial- and final-state leptons is integrated over in boson-proton center-of-mass frame, azimuthal-asymmetric terms vanish, which, however, not true when some physical quantities (such as transverse momentum observed particle) are specified...

A bstract In this paper, we carry out a detailed study on the production of doubly charmed baryon in deeply inelastic ep scattering (DIS) for Q 2 ∈ [2 , 100] GeV at Large Hadron Electron Collider (LHeC) with E e = 60(140) and p 7000 GeV. To exclude contributions from diffractive productions b hadron decays, impose kinematic cuts 0 . 3 &lt; z 9, $$ {p}_{t,\mathrm{baryon}}^{\star 2} <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mi>p</mml:mi> <mml:mrow>...

A bstract In this article, we study in detail the double- J/ψ yield through Z decay at next-to-leading-order (NLO) QCD accuracy within nonrelativistic factorization. At tree level, pure diagrams predict a branching ratio of $$ {\mathcal{B}}_{Z\to J/\psi +J/\psi } <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mi>B</mml:mi> <mml:mrow> <mml:mi>Z</mml:mi> <mml:mo>→</mml:mo> <mml:mi>J</mml:mi> <mml:mo>/</mml:mo> <mml:mi>ψ</mml:mi> <mml:mo>+</mml:mo> </mml:mrow>...

The strip exit thickness is an important indicator for measuring the production quality of steel rolling products. Controlling its accuracy crucial in producing high-quality products industry. This study proposed improved marine predators algorithm (IMPA) optimized bidirectional gated recurrent unit (BiGRU) predicting thickness. Firstly, adaptive weight factor was introduced into (MPA) to overcome drawbacks slow early convergence speed and limited search range algorithm, addressing issue...

By including the interference effect between QCD and QED diagrams, we carry out a complete analysis on exclusive productions of $e^+e^- \to J/\psi+\chi_{cJ}$ ($J=0,1,2$) at $B$ factories with $\sqrt{s}=10.6$ GeV next-to-leading-order (NLO) level in $\alpha_s$, within nonrelativistic framework. It is found that $\mathcal O (\alpha^3\alpha_s)$-order terms represent tree-level are comparable usual NLO corrections, especially for $\chi_{c1}$ $\chi_{c2}$ cases. To explore higher-order terms,...

We present a systematical study on the prompt $J/\ensuremath{\psi}$ production in association with $c\overline{c}$ pair via process, $\ensuremath{\gamma}\ensuremath{\gamma}\ensuremath{\rightarrow}H(c\overline{c})+c+\overline{c}$, within framework of nonrelativistic QCD at future high-energy ${e}^{+}{e}^{\ensuremath{-}}$ collider---International Linear Collider (ILC), including both direct and feed-down contributions. For production, states color-octet channels, especially ${^{3}P}_{J}^{[8]}$...

Within the framework of nonrelativistic quantum chromodynamics, we present a detailed discussion on heavy quarkonium production at leading order in ${\ensuremath{\alpha}}_{s}$ ${e}^{+}{e}^{\ensuremath{-}}$ collider with collision energy around ${Z}^{0}$ peak. Quarkonia are produced through semi-exclusive channels ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}|{H}_{Q\overline{Q}}⟩+X$ $X=Q\overline{Q}$ or $gg$, where $Q$ indicates quark (respectively, $b$ $c$). It is noted that addition...

Double $$J/\psi $$ production in $$e^+e^-$$ collisions involving color-octet channels are evaluated up to order $$\alpha ^2\alpha _s^3$$ . Having implemented the variation of parameters ( $$m_c$$ , $$\mu _r$$ and long-distance matrix elements), we found that cross sections for producing double at B-factories range from $$-0.016$$ 0.245 fb, which even much smaller than via color-singlet mechanism. Accordingly, this result is consistent with measurement by Belle BABAR Collaborations.