We consider the possible contribution of Odderon (Reggeon with alpha_(Odd)(0) similar to 1 and negative signature) exchange to the differences in the total cross sections of particle and antiparticle, to the ratios of real/imaginary parts of the elastic pp amplitude, and to the differences in the inclusive spectra of particle and antiparticle in the central region. The experimental differences in total cross sections of particle and antiparticle are compatible with the existence of the Odderon component but such a large Odderon contribution seems to be inconsistent with the values of Re/Im ratios. In the case of inclusive particle and antiparticle production the current energies and/or accuracy of the experimental data don't allow a clear conclusion. It is expected that the LHC will finally solve the question of the Odderon existence.
我们考虑的第一个大型强子对撞机数据pp碰撞的框架下的Regge理论。由Pomeron交换决定了二次电子的积分截面和包含密度，并给出了相应的预言。对中快度区包含密度的首次测量与这些预言是一致的。Odderon（Reggeon with alpha（Odd）（0）~ 1 and negative signature）交换对中心区域粒子和反粒子包容谱差异的可能贡献在LHC能量下可能是显著的。ALICE合作的第一批数据与Odderon的一个非常小的贡献是一致的。也许，进一步的LHC数据肯定会解决Odderon存在的问题。
There seem to be recently an evidence for $C = -1$ odderon exchange in proton-proton elastic scattering at high energies. Here we discuss three different central-exclusive-production processes $pp \to pp (ϕ\to K^{+}K^{-})$, $pp \to pp (ϕ\to μ^{+}μ^{-})$, and $pp \to pp ϕϕ\to pp K^{+}K^{-}K^{+}K^{-}$, as a possible source of information for soft odderon exchange. The theoretical results are calculated within the tensor-pomeron and vector-odderon model for soft reactions. We include absorptive corrections at the amplitude level. To describe the low-energy data measured in the past by the WA102 c…
We explore the possibility of observing odderon exchange in the $pp \to pp K^{+}K^{-}$ and $pp \to pp μ^{+}μ^{-}$ reactions at the LHC. We consider the central exclusive production (CEP) of the $ϕ(1020)$ resonance decaying into $K^{+} K^{-}$ and $μ^{+}μ^{-}$. We compare the purely diffractive contribution (odderon-pomeron fusion) to the photoproduction contribution (photon-pomeron fusion). The theoretical results are calculated within the tensor-pomeron and vector-odderon model for soft reactions. We include absorptive corrections at the amplitude level. In order to fix the coupling constants …
We explore the possibility of observing Odderon exchange in proton--ion collisions at the LHC, via the ultraperipheral photoproduction of C-even mesons. As well as the signal, we consider in detail the principle backgrounds, due to QCD--initiated production (i.e. double Pomeron exchange) and $γγ$ fusion. We find that while the photon--initiated background is dominant at very small momentum transfer, this can be effectively removed by placing a reasonable cut on the transverse momentum of the produced meson. In the case of QCD--initiated production, we show this is in general strongly suppresse…
We show that the impact of the maximal odderon amplitude at t=0 and centre-of-momentum energy 13 TeV is small. We obtain a value of rho(t=0) at 13 TeV of the order of 0.12. The real part of the odderon amplitude grows like log(s/s0) at high energies, and is calculated from the analytic properties of the amplitude. In the framework of the HEGS model, taking the same intercept for the odderon and the pomeron leads to a good fit of the new LHC data at 13 TeV. We also show that the main effect of the odderon can be seen in the region of the diffraction minimum of the differential elastic cross sec…
The possibility to use the exclusive $pp \to pp ϕ$ and $pp \to pp ϕϕ$ reactions in identifying the odderon exchange is discussed. So far there is no unambiguous experimental evidence for the odderon, the charge conjugation $C = -1$ counterpart of the $C = +1$ pomeron. Recently proposed tensor-pomeron and vector-odderon model for soft high-energy reactions is applied. For the $p p \to p p ϕ$ reaction at high energies the photon-pomeron fusion is the dominant process and the odderon-pomeron fusion is an interesting alternative. Adding odderon exchange improves considerably description of the pro…
Odderon exchange in high-energy $K^0_S$ regeneration at the LHC
Institute of Physics of the Czech Academy of Sciences（捷克科学院物理研究所）；Institute of Physics, Slovak Academy of Sciences（斯洛伐克科学院物理研究所）；Institute for Particle Physics Phenomenology, University of Durham（达勒姆大学粒子物理现象学研究所）；Department of Physics, Lund University（隆德大学物理系）；Petersburg Nuclear Physics Institute, NRC “Kurchatov Institute”（核科学“库尔恰托夫研究所”彼得堡核物理研究所）；L.D. Landau Institute for Theoretical Physics（L.D.朗道理论物理研究所）
We review some selected results of the tensor-pomeron and vector-odderon model of soft high-energy proton-proton scattering and central exclusive production of meson and baryon pairs in proton-proton collisions. We discuss the theoretical aspects of this approach and consider the phenomenological implications in a variety of processes at high energies, comparing to existing experimental data. We consider the diffractive dipion and dikaon production including the continuum and the dominant scalar and tensor resonance contributions as well as the photoproduction processes. The theoretical result…
In this paper one presents a naive parametrization to $pp$ and $\bar{p}p$ total cross sections. The main goal of this parametrization is to study the possible fractal structure present in the total cross section. The result of the fitting procedure shows two different fractal dimensions: a negative (low-energies) and a positive (high-energies). The negative fractal dimension represents the emptiness of the total cross section structure and the positive represents the filling up process with the energy increase. Hence, the total cross section presents a multifractal behavior. At low-energies, t…
Recent results are summarized from the TOTEM experiment at CERN LHC, including measurements of the total, elastic and inelastic cross-sections, the nuclear slope parameter $B$, the differential cross-section of elastic scattering and the real to imaginary part ration $ρ$ at $\sqrt{s} = $ 2.76 and 13 TeV. The implications of these data for Odderon (odd-gluon colorless) exchange are discussed.
In this paper we discuss the Odderon contribution in our model[19] that gives a fairly good description of $σ_{\rm tot}$ $σ_{\rm el}$and $B_{\rm el}$ for proton-proton scattering. We show that the shadowing corrections are large, and induce considerable dependence on energy for the Odderon contribution, which in perturbative QCD does not depend on energy. This energy dependence is in agreement with the experimental data for $ρ= {\rm Re}/{\rm Im}$, assuming that the Odderon gives a contribution of about 1 mb at W = 7 TeV. This differs greatly with our estimates for a CGC based model. We reprodu…
The unitarily extended Bialas-Bzdak model of elastic proton-proton scattering is applied, without modifications, to describe the differential cross-section of elastic proton-antiproton collisions in the TeV energy range, and to extrapolate these differential cross-sections to LHC energies. In this model-dependent study we find that the differential cross-sections of elastic proton-proton collision data at 2.76 and 7 TeV energies differ significantly from the differential cross-section of elastic proton-antiproton collisions extrapolated to these energies. The elastic proton-proton differential…
One of the open questions of the strong interaction theory is the existence of the Odderon, which is an unambiguous prediction of Quantum Chromodynamics, but still not confirmed experimentally. An alternative to probe the Odderon is the exclusive $η_c$ photoproduction in hadronic collisions. As the Pomeron exchange cannot contribute to this process, its observation would indicate the existence of the Odderon. In this paper we estimate the $η_c$ production in photon - induced interactions in hadronic collisions at the AFTER@LHC experiment. We demonstrate that the experimental analysis of this p…
In the present paper, we extend the Froissaron-Maximal Odderon (FMO) approach at $t$ different from 0. Our extended FMO approach gives an excellent description of the 3266 experimental points considered in a wide range of energies and momentum transferred. We show that the very interesting TOTEM results for proton-proton differential cross-section in the range 2.76-13 TeV, together with the Tevatron data for antiproton-proton at 1.8 and 1.96 TeV give further experimental evidence for the existence of the Odderon. One spectacular theoretical result is the fact that the difference in the dip-bum…
It is important to check if the Froissaron-Maximal Odderon (FMO) approach is the only model in agreement with the LHC data. We therefore generalized the FMO approach by relaxing the $\ln^2s$ constraints both in the even-and odd-under-crossing amplitude. We show that, in spite of a considerable freedom of a large class of amplitudes, the best fits bring us back to the maximality of strong interaction. Moreover, if we leave Odderon Regge pole intercept $α_O(0)$ completely free we find a very good solution for $α_O(0)$ near -1 in agreement with the result of oddballs spectroscopy in QCD based on …
Possible Odderon Effects in Hadron-Nucleon Scattering
我们考虑了Odderon交换（Reggeon with α_{Odd}（0）\sim 1 and negative signature）对粒子和反粒子总截面之差、弹性pp振幅的实部/虚部之比以及中心区粒子和反粒子包容谱之差的可能贡献。粒子和反粒子总截面的实验差异与Odderon分量的存在是一致的，但如此大的Odderon贡献似乎与Re/Im比值不一致。在包含粒子和反粒子产生的情况下，目前的能量和/或实验数据的准确性不允许明确的结论。
Inspired by the new TOTEM data on elastic $pp$ scattering at 13 TeV, we study the possibility to describe all the diffractive collider data ($σ_{\rm tot}, dσ_{\rm el}/dt$, $ρ\equiv$Re$A$/Im$A$, \sd) in a wide interval of energy (0.0625 to 13 TeV) in the framework of a two-channel eikonal model. We show that a satisfactory description can be achieved without an odd-signature (Odderon) exchange contribution. We consider the possible role of the QCD Odderon which may improve the description of $ρ$ and discuss the importance of the odd-signature term if the amplitude were to exceed the black disc …
Odderon and photon exchange in electroproduction of pseudoscalar mesons
我们研究了反应$e p \to e PS X$，其中PS表示赝标介子$π^0, η, η'$，或$η_c$，X表示质子或共振态或连续态，质子可以通过衍射激发进入连续态。在高能量下，光子和odderon交换有助于反应。光子交换的贡献，准确地评估使用的总虚拟光子-质子吸收截面的数据。本文用泛函积分方法和随机真空模型计算了非微扰QCD中奇子交换的贡献。对于质子，我们假设一个夸克-双夸克结构，这是由$pp$和$p \bar{p}$前向散射中的小奇子振幅所暗示的。我们发现，odderon交换导致一个更大的非弹性比弹性PS生产截面。我们在HERA的反应的观察将建立软odderon作为一个交换对象在平等的基础上与软pomeron，并会给我们提供宝贵的洞察核子结构和高能衍射散射的机制。
There seem to be recently an evidence for $C =$ -1 exchanges in $p p$ and $p \bar p$ elastic scattering at high energies. The analysis there is difficult as the two processes were not measured at the same (large) energies. Here we discuss three different exclusive processes given in the title as a possible source of information for odderon exchange. A sketch of the formalism is presented for each of the reactions. We consider low energy processes measured in the past by the WA102 collaboration and try to make predictions for the LHC. We discuss possible evidences at the low energies and try to…
Although the Odderon is an unambiguous prediction of Quantum Chromodynamics, its existence still was not confirmed experimentally. One of the processes where the Odderon contribution is expected to be dominant is the diffractive photoproduction of tensor mesons. In this paper we study the diffractive $f_2(1270)$ photoproduction in $pA$ collisions at LHC and RHIC considering the model of the stochastic vacuum to treat the non - perturbative process. We demonstrate that this process dominates the $f_2$ production at mid - rapidities, and large values for the cross section are predicted. Our resu…
We study the scaling properties of the differential cross section of elastic proton-proton ($pp$) and proton-antiproton ($p\bar p$) collisions at high energies. We introduce a new scaling function, that scales -- within the experimental errors -- all the ISR data on elastic $pp$ scattering from $\sqrt{s} = 23.5$ to $62.5$ GeV to the same universal curve. We explore the scaling properties of the differential cross-sections of the elastic $pp$ and $p\bar p$ collisions in a limited TeV energy range. Rescaling the TOTEM $pp$ data from $\sqrt{s} = 7$ TeV to $2.76$ and $1.96$ TeV, and comparing it t…
A novel model-independent Lévy imaging method is employed for reconstruction of the elastic $pp$ and $p\bar p$ scattering amplitudes at low and high energies. The four-momentum transfer $t$ dependent elastic slope $B(t)$, the nuclear phase $ϕ(t)$ as well as the excitation function of the shadow profile $P(b)$ have been extracted from data at ISR, Tevatron and LHC energies. We found qualitative differences in properties of $B(t)$ and $ϕ(t)$ between $pp$ and for $p\bar p$ collisions, that indicate an Odderon effect. A proton substructure has also been identified and found to have two different s…
At high center-of-mass energies scattering amplitudes enjoy a hidden integrability. An important example in QCD is Odderon exchange, a composite state of three reggeized gluons, with can be understood as a closed spin chain with periodic boundary conditions. In the N=4 supersymmetric Yang-Mills theory a similar open spin chain appears for the planar eight-point amplitude. We solve these two examples in transverse momentum and rapidity space, introducing the concept of weighted graph complexity and its associated emerging scaling laws.
We describe a new and model-independent Lévy imaging method of quality fits to the published datasets and reconstruct the amplitude of high-energy $pp$ and $p\bar p$ elastic scattering processes. This method allows us to determine the excitation function of the shadow profile $P(b)$, the elastic slope $B(t)$ and the nuclear phase $ϕ(t)$ functions of $pp$ and $p\bar p$ collisions directly from the data. Surprisingly, notable qualitative differences in $B(t)$ for $pp$ and for $p\bar p$ collisions point towards an Odderon effect. As a by-product, we clearly identify the proton substructure with t…
We present a study of the exclusive $pp \to pp K^{+} K^{-} K^{+} K^{-}$ reaction at high energies. We consider diffractive mechanisms with the intermediate $ϕϕ$ state with its decay into the $K^{+} K^{-} K^{+} K^{-}$ system. We include the $ϕ(1020)$ $\hat{t}/\hat{u}$-channel exchanges and the $f_{2}(2340)$ $s$-channel exchange mechanism. This $f_{2}$ state is a candidate for a tensor glueball. We discuss the possibility to use the $pp \to pp ϕϕ$ process in identifying the odderon exchange. An upper limit for the $\mathbb{P} \mathbb{O} ϕ$ coupling is extracted from the WA102 experimental data. …
Exclusive $p p \to p p π^{0}$ reaction at high energies
详细讨论了适用于高能量的$p p \to p p π^{0}$过程的振幅。衍射韧致辐射（Drell-Hiida-Deck型模型），光子-光子和光子-ω交换机制都包括在计算中。预测了mb量级的大截面。计算了RHIC和LHC能区质子和π介子的快度和横动量的微分截面以及出射质子之间的相对方位角。强子韧致辐射的贡献在大的（前向，后向）π介子快度下占主导地位。衍射非共振背景在小的$π^0 p$不变质量下有贡献，因此可能被误解为罗珀共振。我们预测强烈的依赖性的斜率在$t$（平方四动量转移之间的进出质子）的补充激发$π^{0}p$系统的质量。在高能量和中等速度下，光子-光子贡献在衍射分量上占主导地位，然而，相应的截面相当小。此外，还包括光子-odderon和odderon-光子的贡献，并给出了它们对中性π介子快度和横动量分布的贡献的初步估计（上限）。我们建议在中快度和$p_{\perp,π^{0}} \sim$ 0.5 GeV的odderon贡献的搜索。我们的预测已经准备好在RHIC和LHC上进行验证。这里讨论的韧致辐射机制也有助于$pp \to p(n π^{+})$反应。这两个通道都对低质量单衍射截面有相当大的贡献，必须包括在外推测得的实验单衍射截面中。
