在非粒子物理学中，共形扇区的算符具有自相互作用，并且这些自相互作用对于强耦合是不受抑制的。三点相互作用完全由共形对称决定，直到一个常数。我们不知道这个常数的任何理论上限。施加目前的实验限制，我们发现，这些相互作用介导壮观的对撞机信号，如$pp -> U -> UU -> γγγγ$，$γγZZ$，$ZZZZ$，$γγl^+ l^-$，$ZZ l^+ l^-$，和$4l$，与截面的皮巴或更大的大型强子对撞机。因此，自相互作用可能为非粒子物理学提供领先的发现前景。
英文摘要：
In unparticle physics, operators of the conformal sector have self-interactions, and these are unsuppressed for strong coupling. The 3-point interactions are completely determined by conformal symmetry, up to a constant. We do not know of any theoretical upper bounds on this constant. Imposing current experimental constraints, we find that these interactions mediate spectacular collider signals, such as $pp -> U -> UU -> γγγγ$, $γγZZ$, $ZZZZ$, $γγl^+ l^-$, $ZZ l^+ l^-$, and $4l$, with cross sections of picobarns or larger at the Large Hadron Collider. Self-interactions may therefore provide the leading discovery prospects for unparticle physics.
An attempt is made to present the influence of the scalar unparticle on some scattering processes in the Randall - Sundum model. The contribution of the scalar unparticle on the production of Higgs - radion at high energy colliders is studied in detail. We evaluate the production cross-sections in the electron-positron ($e^{+}e^{-}$), photon-photon ($γγ$) and gluon-gluon ($gg$) collisions, which depend strongly on the collision energy $\sqrt{s}$, the scaling dimension $d_{U}$ of the unparticle operator $\mathcal{O}_{U}$ and the energy scale $Λ_{U}$. Numerical evaluation shows that the cross - …
An attempt is made to present the contribution of the scalar unparticle on some scattering processes in the Randall - Sundum (RS) model. We have evaluated the contribution of the scalar unparticle on the W - pair production cross-sections at International Linear Colliders (ILC). The results indicate that at the low values of the scaling dimension and the bounds on scale $Λ_{U}$ are around few TeV, the cross-sections are much enhanced, which is quite comparable with the W-production in the standard model and hence it is worthwhile to explore in future colliders.
Constraints on Unparticle Physics from Solar and KamLAND Neutrinos
最近，人们的兴趣已经转向具有IR不动点（Λ）的有效场论的非平凡共形扇区的低能含义，表现为具有奇异性质的“非粒子”。我们重新研究了太阳中微子衰变寿命的极限对非粒子相互作用的影响。我们详细研究了基本参数空间（Λ，M），并推导出表征新物理的能量标度M的界限。我们的工作严格的框架内，共形不变性举行了低能量。我们首先假设非粒子扇区与希格斯场的耦合被抑制，并从中微子衰变为标量非粒子导出在TeV区域中的Λ的界限。这些界限对于非粒子算子的反常维数1.0 < d < 1.2的值是重要的。对于一个区域的参数空间，我们表明，边界是可比的生产率在高能量对撞机。然后我们放松我们的假设，考虑一个更自然的框架，不需要先验限制的希格斯粒子的耦合操作，并推导出在meV区域从中微子衰变到矢量非粒子与Λ的界限。IR不动点的这种低标度在各种风格的规范理论中都有相关性。
If the scale invariance exists in nature, the so-called unparticle physics may become part of reality. The only way to refute or confirm this idea is through the experiments one of which is the Large Hadron Collider (LHC). One of the peculiar properties of the unparticle stuff is that it gives striking multi-photon signals which has been studied through only the unparticle self-interactions. By considering not only the self-interactions of unparticles but also all the other possible contributions, which are dominant, a detailed study of the processes, within a scalar unparticle scenario, $pp\t…
The existence of the $X(3872)$ resonance extremely close to the $D^{*0} \bar{D}^0$ threshold implies that neutral charm mesons have an approximate nonrelativistic conformal symmetry. Systems consisting of these mesons with small kinetic energies produced in a short-distance reaction are unparticles in the sense that they can be created by operators with definite scaling dimensions in a nonrelativistic conformal field theory. There is a scaling region in which their energy distribution has power-law behavior with an exponent determined by the scaling dimension of the operator. The unparticle as…
Two of the important implications of the seesaw mechanism are: (i) a simple way to understand the small neutrino masses, and (ii) the origin of matter-anti-matter asymmetry in the universe via the leptogenesis mechanism. For TeV-scale seesaw models, successful leptogenesis requires that the right-handed neutrinos (RHNs) must be quasi-degenerate and if they have CP violating phases, they also contribute to the CP asymmetry. We investigate this in the TeV-scale left-right models for seesaw and point out a way to probe the quasi-degeneracy possibility with CP violating mixings for RHNs in hadron …
We review the constraints on the small-x gluon PDF that can be derived by exploiting the forward D meson production data from the LHCb experiment at $\sqrt{s}=5,7$ and 13 TeV. We then discuss the phenomenological implications of the resulting improved small-x gluon for ultra-high energy astrophysics, in particular neutrino telescopes, as well as for the proposed Future Circular Collider (FCC) with $\sqrt{s}=100$ TeV. We illustrate how at the FCC even electroweak scale cross-sections can become sensitive to the small-x region of the quark and gluon PDFs, and then demonstrate how the addition of…
Many composite Higgs models predict the existence of vector-like quarks with masses outside the reach of the LHC, e.g. $m_Q \gtrsim 2$ TeV, in particular if these models contain a dark matter candidate. In such models the mass of the new resonances is bounded from above to satisfy the constraint from the observed relic density. We therefore develop new strategies to search for vector-like quarks at a future $100$ TeV collider and evaluate what masses and interactions can be probed. We find that masses as large as $\sim 6.4$ ($\sim 9$) TeV can be tested if the fermionic resonances decay into St…
Light Gravitinos at Colliders and Implications for Cosmology
质量在eV到MeV范围内的轻引力子在粒子物理学中很有意义，但它们作为暗物质候选者的地位被早期宇宙的不确定性所混淆。我们调查即将到来的数据从对撞机可能会澄清这一情况。轻引力子主要产生于次轻的超对称粒子的衰变中，产生壮观的信号，包括双光子，延迟和非指向光子，扭结带电轨道和重亚稳态带电粒子。我们发现20/fb的Tevatron和1/fb的7 TeV LHC都可能看到数百个光引力子事件的证据。值得注意的是，这个对撞机数据也非常适合区分目前可行的光引力子场景，对结构形成，膨胀和其他早期宇宙学具有显着的影响。
Type-III seesaw is a simple extension of the Standard Model~(SM) with the SU$(2)_\text{L}$ triplet fermion with zero hypercharge. It can explain the origin of the tiny neutrino mass and flavor mixing. After the electroweak symmetry breaking the light neutrino mass is generated by the seesaw mechanism which further ensures the mixings between the light neutrino and heavy neutral lepton mass eigenstates. If the triplet fermions are around the electroweak scale having sizable mixings with the SM sector allowed by the correct gauge symmetry, they can be produced at the high energy colliders leavin…
The neutrino masses and flavor mixings, which are missing in the Standard Model (SM), can be naturally incorporated in the type-I seesaw extension of the SM with heavy Majorana neutrinos being singlet under the SM gauge group. If the heavy Majorana neutrinos are around the electroweak scale and their mixings with the SM neutrinos are sizable, they can be produced at high energy colliders, leaving characteristic signatures with lepton-number violations. Employing the general parametrization for the neutrino Dirac mass matrix in the minimal seesaw scenario, we perform a parameter scan and identi…
Addendum/Erratum for `Searching for Invisible and Almost Invisible Particles at $\bf e^+e^-$ Colliders' [hep-ph/9512230] and `A Non-Standard String/SUSY Scenario and its Phenomenological Implications' [hep-ph/9607421]
