Aspects of Unparticle Physics

Another Odd Thing About Unparticle Physics

The peculiar propagator of scale invariant unparticles has phases that produce unusual patterns of interference with standard model processes. We illustrate some of these effects in $e^+e^-\toμ^+μ^-$.

2007-05-21hep-ph

Constraints of unparticle physics parameters from $K^0-\bar K^0$ mixing

The neutral kaon meson mixing plays an important role in test of the Standard Model (SM) and new physics beyond it. Scale invariant unparticle physics induces a flavor changing neutral current (FCNC) transition of $K^0-\bar K^0$ oscillation at the tree level. In this study, we investigate the scale invariant unparticle physics effects on the $K^0-\bar K^0$ mixing. Based on the current experimental data, we give constraints of $K^0-\bar K^0$ mixing on the unparticle parameters.

2013-04-01hep-ph

Unparticle physics in top pair signals at the LHC and ILC

We study the effects of unparticle physics in the pair productions of top quarks at the LHC and ILC. By considering vector, tensor and scalar unparticle operators, as appropriate, we compute the total cross sections for pair production processes depending on scale dimension $d_{\U}$. We find that the existence of unparticles would lead to measurable enhancements on the SM predictions at the LHC. In the case of ILC this may become two orders of magnitude larger than that of SM, for smaller values of $d_\U$, a very striking signal for unparticles.

2007-12-12hep-ph

Muon Anomalous Magnetic Moment and Lepton Flavor Violating Tau Decay in Unparticle Physics

We study effects of unparticle physics on muon g-2 and LFV tau decay processes. LFV interactions between the Standard Model sector and unparticles can explain the difference of experimental value of muon g-2 from the Standard Model prediction. While the same couplings generate LFV tau decay, we found that LFV coupling can be of O(0.1 ... 1) without conflict with experimental bounds of LFV tau decay if the scaling dimension of unparticle operator d_{U} > 1.6.

2008-10-02hep-ph

Unparticle Physics in DIS

The unparticle stuff scenario related to the notrivial IR fixed point in 4D-conformal field theory is recently suggested by Georgi. We illustrate its physical effects in Deep Inelastic Scattering (DIS) process. A possible signal of unparticle related to parity violation asymmetry in DIS is investigated. It is found out that the behavior of this parity violation signal is sensitive to the value of the scale dimension $d_{\cal U}$ of unpaticle.

2007-08-20hep-ph

Neutrino, Photon Interaction in Unparticle Physics

We investigate the impact of unparticle physics on the annihilation of relic neutrinos with the neutrinos identified as primary source of ultra high energy (UHE) cosmic ray events, producing a cascade of photons and charged particles. We compute the contribution of the unparticle exchange to the cross-sections $ν\barν\toγγ$ and $ν\barν\to f \bar f$ scattering. We estimate the neutrino photon decoupling temperature from the reaction rate of $ν\barν\toγγ$. We find that inclusion of unparticles can in fact account for the flux of UHE cosmic rays and can also result in the lowering of neutrino - p…

2008-01-14hep-ph

A solution to the mu problem in the supersymmetric unparticle physics

Recently, conceptually new physics beyond the Standard Model has been proposed by Georgi, where a new physics sector becomes conformal and provides "unparticle" which couples to the Standard Model sector through higher dimensional operators in low energy effective theory. Among several possibilities, we focus on operators involving the (scalar) unparticle, Higgs and the gauge bosons. Once the Higgs develops the vacuum expectation value (VEV), the conformal symmetry is broken and as a result, the mixing between the unparticle and the Higgs boson emerges. In this paper, we consider the unparticl…

2008-12-25hep-ph

Unparticle Physics Effects on D0-anti-D0 Mixing

The mixing of $K^0-\bar{K^0}$, $D^0-\bar{D^0}$ and $B_{(s)}^0-\bar{B^0_{(s)}}$ provides a sensitive probe to explore new physics beyond the Standard Model. The scale invariant unparticle physics recently proposed by Georgi can induce flavor-changing neutral current and contribute to the mixing at tree level. We investigate the unparticle effects on $B^0-\bar{B^0}$ and $D^0-\bar{D^0}$ mixing. Especially, the newly observed $D^0-\bar{D^0}$ mixing sets the most stringent constraints on the coupling of the unparticle to quarks.

2007-06-21hep-ph

Lepton Flavour Violation in Unparticle Physics

Recently H. Georgi has introduced an unparticle $\unpart$ in order to describe the low energy physics of a nontrivial scale invariant sector of an effective theory. In this work we have explored the phenomenology of an unparticle using the lepton flavour violating decay $μ^{-}\to e^{-} e^{+} e^{-}$, and found that the branching ratio of this decay is strongly dependent on the scaling dimension.

2007-05-14hep-ph

Unparticle physics effects in (Lambda_b -> Lambda + missing energy) processes

We study unparticle physics effects in (Lambda_b -> Lambda + missing energy) decay with polarized $Λ_b$ and $Λ$ baryons. The sensitivity of the branching ratio of this decay and polarizations of (Lambda_b) and (Lambda) baryons on the scale dimension d_U and effective cut-off parameter (Lambda_U) are discussed.

2007-10-08hep-ph

Unparticle Physics And Gauge Coupling Unification

Unparticle physics from a hidden conformal sector can alter the evolution of the Standard Model (SM) gauge couplings via TeV scale threshold corrections. We discuss how this may lead to gauge coupling unification at M_{GUT}\approx 2 \times 10^{15} GeV -- 5 \times 10^{17} GeV without introducing new particles in the SM sector.

2007-08-31hep-ph

Unparticle Physics in the Moller Scattering

We investigate the virtual effects of vector unparticles in the Moller scattering. We derive the analytic expression for scattering amplitudes with unpolarized beams. We obtain 95% confidence level limits on the unparticle couplings $λ_{V}$ and $λ_{A}$ with integrated luminosity of $L_{int}=50, 500 fb^{-1}$ and $\sqrt{s}=100, 300$ and 500 GeV energies. We show that limits on $λ_{V}$ are more sensitive than $λ_{A}$.

2008-04-13hep-ph

B \to K(K^*) missing energy in Unparticle physics

In the present work we study the effects of an unparticle $\unpart$ as the possible source of missing energy in the decay $B \to K (K^*) + {\rm missing energy}$. We find that the dependence of the differential branching ratio on the $K$($K^*$)-meson's energy in the presence of the vector unparticle operators is very distinctive from that of the SM. Moreover, in using the existing upper bound on $B \to K (K^*) + {\rm missing energy}$ decays, we have been able to put more stringent constraints on the parameters of unparticle stuff.

2007-05-31hep-ph

Collider signals in unparticle physics

Phenomenology of the notion of an unparticle U, recently perceived by Georgi, to describe a scale invariant sector with a non-trivial infrared fixed point at a higher energy scale is explored in details. Behaving like a collection of d_U (the scale dimension of the unparticle operator O_U) invisible massless particles, this unparticle can be unveiled by measurements of various energy distributions for the processes Z to fermion pair + U and e-e+ to gamma U at e-e+ colliders, as well as mono-jet production at hadron colliders. We also study the propagator effects of the unparticle through the D…

2007-08-09hep-ph

Bosonic Seesaw in the Unparticle Physics

Recently, conceptually new physics beyond the Standard Model has been proposed by Georgi, where a new physics sector becomes conformal and provides "unparticle" which couples to the Standard Model sector through higher dimensional operators in low energy effective theory. Among several possibilities, we focus on operators involving the (scalar) unparticle, Higgs and the gauge bosons. Once the Higgs develops the vacuum expectation value (VEV), the conformal symmetry is broken and as a result, the mixing between the unparticle and the Higgs boson emerges. In this paper, we consider a natural rea…

2008-12-25hep-ph

Unparticle Physics

I discuss some simple aspects of the low-energy physics of a nontrivial scale invariant sector of an effective field theory -- physics that cannot be described in terms of particles. I argue that it is important to take seriously the possibility that the unparticle stuff described by such a theory might actually exist in our world. I suggest a scenario in which some details of the production of unparticle stuff can be calculated. I find that in the appropriate low energy limit, unparticle stuff with scale dimension $d_{\mathcal{U}}$ looks like a non-integral number $d_{\mathcal{U}}$ of invisib…

2007-05-20hep-ph

Lepton flavor violating $μ\to eγ$ and $μ-e$ conversion in unparticle physics

We have studied lepton flavor violation processes $μ\to eγ$ and $μ-e$ conversion in nuclei induced by unparticle. Both ${\rm Br}(μ\to eγ)$ and $μ-e$ conversion rate ${\rm CR}(μ-e,{\rm Nuclei})$ strongly depend on the scale dimension $d_{\cal U}$ and the unparticle coupling $λ^{ff'}_{\rm K}$(K=V, A, S, P). Present experimental upper bounds on ${\rm Br}(μ\to eγ)$, ${\rm CR}(μ-e,{\rm Ti})$ and ${\rm CR}(μ-e,{\rm Au})$ put stringent constraints on the parameters of unaprticle physics. The scale dimensions $d_{\cal U}$ around 2 are favored for the unparticle scale $Λ_{\cal U}$ of ${\cal O}(10 {\rm …

2008-11-28hep-ph

W-pair production in Unparticle Physics

We consider the $W$-pair production for both $e^+e^-$ and hadron colliders in the context of unparticle physics associated with the scale invariant sector proposed by Georgi. We have shown that the unparticle contributions are quite comparable with standard model (SM) specially for low values of non-integral scaling dimension $ (d_{\cal U}) $ and hence it is worthwhile to explore in future colliders.

2007-11-06hep-ph

Lepton flavor violating Higgs decays and unparticle physics

We predict the branching ratios of the lepton flavor violating Higgs decays H^0->e^{\pm} μ^{\pm}, H^0-> e^{\pm} τ^{\pm} and H^0->μ^{\pm} τ^{\pm} in the case that the lepton flavor violation is carried by the scalar unparticle mediation. We observe that their branching ratios are strongly sensitive to the unparticle scaling dimension and they can reach to the values of the order of $10^{-4}$, for the heavy lepton flavor case and for the small values of the scaling dimension.

2008-09-21hep-ph

On the difference of time-integrated $CP$ asymmetries in $D^0\rightarrow K^+K^-$ and $D^0\rightarrowπ^+π^-$ decays: unparticle physics contribution

The LHCb Collaboration has recently measured the difference of time-integrated $CP$ asymmetry in $D^{0}\rightarrow K^{+}K^{-}$ and $D^{0}\rightarrow π^{+}π^{-}$ decays, more precisely. The reported value is $ ΔA_{CP}=-0.10 \pm 0.08 (\text{stat}) \pm 0.03 (\text{syst})\% $ which indicates no evidence for $CP$ violation. We consider the possible unparticle physics contribution in this quantity and by using the LCHb data try to constrain the parameter space of unparticle stuff.

2017-06-13hep-ph

B \to 0^{+}(1^{+}) + missing energy in Unparticle Physics

We examine the effects of an unparticle $\mathcal{U}$ as a possible source of missing energy in the p-wave decays of $B$ meson. The dependence of the differential branching ratio on the $K_{0}^{\ast}(K_{1}) -$% meson's energy is discussed in the presence of scalar and vector unparticle operators and significant deviation from the standard model value is found after addition of these operators. Finally, we have shown the dependence of branching ratio for the above said decays on the parameters of the unparticle stuff like the effective couplings, cutoff scale $Λ_{% \mathcal{U}}$ and the scale d…

2008-09-02hep-ph

Unparticle Physics and A_{FB}^b on the Z pole

An attempt has been made to address the 3σanomaly of the forward-backward asymmetry of b quark in LEP data via an unparticle sector. For most part of the parameter space except certain particular regions, the anomaly could not be explained away plausibly, when constraints from other LEP observables are taken into account.

2008-01-03hep-ph

Bounds on Unparticles from the Higgs Sector

We study supersymmetric QCD in the conformal window as a laboratory for unparticle physics, and analyze couplings between the unparticle sector and the Higgs sector. These couplings can lead to the unparticle sector being pushed away from its scale invariant fixed point. We show that this implies that low energy experiments will not be able to see unparticle physics, and the best hope of seeing unparticles is in high energy collider experiments such as the Tevatron and the LHC. We also demonstrate how the breaking of scale invariance could be observed at these experiments.

2007-05-22hep-ph

The large CP phase in B(s) - anti-B(s) mixing and Unparticle Physics

In this work we investigate the contribution to B(d,s) mixing from both scalar and vector unparticles in a number of scenarios. The emphasis of this work is to show the impact of the recently discovered 3 sigma evidence for new physics found in the CP phase of B(s) mixing. Here we show that the inclusion of the CP phase constraints for both B(d) and B(s) mixing improves the bounds set on the unparticle couplings by a factor of 2~4, and one particular scenario of scalar unparticles is found to be excluded by the 3 sigma measurement of phi(s).

2009-01-12hep-ph

Unparticle Physics and Supersymmetry Phenomenology

We show a natural form of the interaction between unparticle and supersymmetry. Using the couplings of unparticle to supersymmetry presented, as examples, we calculate the differential decay rates for the processes ${\it {\tilde f}}\to {\it f}+{\cal U}_{3/2}$, ${\it {\tilde χ}}^0\to{\it γ}+{\cal U}_{3/2}$, ${\it {\tilde χ}}^\pm\to W^\pm+{\cal U}_{3/2}$ and ${\it {\tilde χ}}^0\to Z^0+{\cal U}_{3/2}$. Finally, we discuss the phenomenological implication of our results and give some comments.

2007-10-30hep-ph

Astro Unparticle Physics

We investigate the effects of all flavor blind CP-conserving unparticle operators on 5th force experiments, stellar cooling, supernova explosions and compare the limits with each other and with those obtainable from collider experiments. In general, astrophysical bounds are considerably stronger, however they depend strongly on the dimension d_U of the unparticle operator. While for d_U=1, 5th force experiments yield exceedingly strong bounds, the bounds from stellar and supernova cooling are more comparable for d_U=2, with stellar cooling being most restrictive. Bounds on vectorial unparticle…

2007-12-10hep-ph

The decay of singlet scalar dark matter to unparticle and photon

We consider the unparticle physics introduced by Georgi and show that if the standard model is extended to include a singlet scalar as a dark matter candidate, there is a channel which leads to its decay to photon and unparticle. We calculate the decay rate for this new channel and find a lower bound on unparticle physics scale by demanding the stability of this candidate of the dark matter.

2022-05-04hep-ph

Unparticle physics and lepton flavor violating radion decays in the Randall-Sundrum scenario

We predict the branching ratios of the lepton flavor violating radion decays r -> e^{\pm} μ^{\pm}, r -> e^{\pm} τ^{\pm} and r ->μ^{\pm} τ^{\pm} in the framework of the Randall-Sundrum scenario that the lepton flavor violation is carried by the scalar unparticle mediation. We observe that their BRs are strongly sensitive to the unparticle scaling dimension and, for its small values, the branching ratios can reach to the values of the order of 10^{-8}, for the heavy lepton flavor case.

2007-11-17hep-ph

Unparticle Physics with Jets

Using methods of effective field theory, we show that after resummation of Sudakov logarithms the spectral densities of interacting quark and gluon fields in ordinary quantum field theories such as QCD are virtually indistinguishable from those of "unparticles" of a hypothetical conformal sector coupled to the Standard Model, recently studied by Georgi. Unparticles are therefore less exotic that originally thought. Models in which a hidden sector weakly coupled to the Standard Model contains a QCD-like theory, which confines at some scale much below the characteristic energy of a given process…

2008-01-22hep-ph

Constraints on Unparticle Physics from Solar and KamLAND Neutrinos

Interest has been directed recently towards low energy implications of a non-trivial conformal sector of an effective field theory with an IR fixed point (Λ), manifest in terms of ``unparticles'' with bizarre properties. We re-examine the implications of the limits on decay lifetimes of solar neutrinos for unparticle interactions. We study in detail the fundamental parameter space (Λ, M) and derive bounds on the energy scale M characterizing the new physics. We work strictly within the framework where conformal invariance holds down to low energies. We first assume that couplings of the unpart…

2007-11-02hep-ph

Unparticle Phenomenology -- A Mini Review

We review some collider phenomenology of unparticle physics, including real emissions and virtual exchanges of unparticle. Existing experimental constraints from collider physics as well as astrophysics are briefly discussed.

2008-09-14hep-ph

Lepton flavor violating processes in unparticle physics

We study the virtual effects of unparticle physics in the lepton flavor violating processes $M^0\to l^+l'^-$ and $e^+e^-\to l^+l'^-$ scattering, where $M^0$ denotes the pseudoscalar mesons: $π^0,K_L, D_0,B_0,B_s^0$ and $l,l'$ denote two different lepton flavors. For the decay of $B^0\to l^+l'^-$, there is no constraint from the current experimental upper bounds on the vector unparticle coupling with leptons. The constraint on the coupling constant between scalar unparticle field and leptons is sensitive to the scaling dimension of the unparticle $d_{\cal U}$. For the scattering process $e^-e^+…

2007-09-03hep-ph

Unparticle effects in rare (t -> c g g) decay

Rare (t -> c g g) decay can only appear at loop level in the Standard Model (SM), and naturally they are strongly suppressed. These flavor changing decays induced by the mediation of spin-0 and spin-2 unparticles, can appear at tree level in unparticle physics. In this work the virtual effects of unparticle physics in the flavor-changing (t -> c g g) decay is studied. Using the SM result for the branching ratio of the (t -> c g g) decay, the parameter space of d_U and Lambda_U, where the branching ratio of this decay exceeds the one predicted by the SM, is obtained. Measurement of the branchin…

2008-05-08hep-ph

Unparticle physics and neutrino phenomenology

We have constrained unparticle interactions with neutrinos and electrons using available data on neutrino-electron elastic scattering and the four CERN LEP experiments data on mono photon production. We have found that, for neutrino-electron elastic scattering, the MUNU experiment gives better constraints than previous reported limits in the region d>1.5. The results are compared with the current astrophysical limits, pointing out the cases where these limits may or may not apply. We also discuss the sensitivity of future experiments to unparticle physics. In particular, we show that the measu…

2009-05-14hep-ph

Lepton flavor violation decays of vector mesons in unparticle physics

We investigate the lepton flavor violation decays of vector mesons in the scenario of the unparticle physics by considering the constraint from $μ-e$ conversion. In unparticle physics, the predictions of LFV decays of vector mesons depend strongly on the scale dimension $d_{\mathcal{U}}$. The predictions of LFV decays of vector mesons can reach the detective sensitivity in experiment in region of $3\le d_{\mathcal{U}}\le 4$, while the prediction of $μ-e$ conversion rate can meet the experimental upper limit. For the searching of the lepton flavor violation processes of charged lepton sector in…

2013-12-07hep-ph

Cosmology with Unparticles

We discuss cosmological consequences of the existence of physics beyond the standard model that exhibits Banks-Zaks and unparticle behavior in the UV and IR respectively. We first derive the equation of state for unparticles and use it to obtain the temperature dependence of the corresponding energy and entropy densities. We then formulate the Boltzmann and Kubo equations for both the unparticles and the Banks-Zaks particles, and use these results to determine the equilibrium conditions between the standard model and the new physics. We conclude by obtaining the constraints on the effective nu…

2009-12-03hep-ph

Neutrino phenomenology and unparticle physics

We show how neutrino data can be used in order to constrain the free parameters of possible extensions to the standard model of elementary particles (SM). For definiteness, we focus in the recently proposed unparticle scenario. We show that neutrino data, in particular the MUNU experiment, can set stronger bounds than previous reported limits in the scale dimension parameter for certain region (d > 1.5). We compute the sensitivity of future neutrino experiments to unparticle physics such as future neutrino-electron scattering detectors, coherent neutrino-nuclei scattering as well as the ILC . …

2009-11-10hep-ph

Forward-backward asymmetry of top quark in unparticle physics

The updated CDF measurement of the forward-backward asymmetry (FBA) in the top quark production p{bar p} -> t{bar t} at Tevatron (with the CMS energy 1.96 TeV) shows a deviation of 2*sigma from the value predicted by the Standard QCD Model. We present calculation of this quantity in the scenario where colored unparticle physics contributes to the s-channel of the process, and obtain the regions in the plane of the unparticle parameters lambda and dU which give the values of the FBA and of the total t{bar t} production cross section compatible with the present measurements.

2010-11-03hep-ph

Unparticle effects in neutrino telescopes

Recently H.Georgi has introduced the concept of unparticles in order to describe the low energy physics of a nontrivial scale invariant sector of an effective theory. We investigate its physical effects on the neutrino flux to be detected in a kilometer cubic neutrino telescope such as IceCube. We study the effects, on different observables, of the survival neutrino flux after through the Earth and the regeneration originated in the neutral currents. We calculate the contribution of unparticle physics to the neutrino-nucleon interaction and, then, to the observables in order to evaluate detect…

2009-03-06hep-ph

Collider Effects of Unparticle Interactions in Multiphoton Signals

A new model of physics, with a hidden conformal sector which manifests itself as an unparticle coupling to Standard Model particles effectively through higher dimensional operators, predicts strong collider signals due to unparticle self-interactions. We perform a complete analysis of the most spectacular of these signals at the hadron collider, pp -> 4photon and pp ->2photon,2gluon. These processes can go through the three-point unparticle self interactions as well as through some s and t channel diagrams with one and/or two unparticle exchanges. We study the contributions of individual diagr…

2009-10-28hep-ph

Tensorial NSI and Unparticle physics in neutrino scattering

We have analyzed the electron anti-neutrino scattering off electrons and the electron anti-neutrino-nuclei coherent scattering in order to obtain constraints on tensorial couplings. We have studied the formalism of non-standard interactions (NSI), as well as the case of Unparticle physics. For our analysis we have focused on the recent TEXONO collaboration results and we have obtained current constraints to possible electron anti-neutrino-electron tensorial couplings in both new physics formalisms. The possibility of measuring for the first time electron anti-neutrino-nucleus coherent scatteri…

2012-08-31hep-ph

Investigation of $B_{u,d}\to (π, K) π$ decays within unparticle physics

We investigate the implication of unparticle physics on the B_{u,d}\to (π, K) πdecays under the constraints of the B_{d,s}-\bar B_{d,s} mixing. We found that not only the unparticle parameters that belong to the flavor changing neutral current (FCNC) processes but also scaling dimension d_{\UP} could be constrained by the B_{d,s}-\bar B_{d,s} mixing phenomenology. Employing the minimum χ^2 analysis to the B_{u,d}\to (π, K) πdecays with the constraints of B_{d,s} mixing, we find that the puzzle of large branching ratio for B_{d}\to π^0 π^0 and the discrepancy between the standard model estimati…

2008-12-15hep-ph

Unparticle physics at the photon collider

Recently, a conceptually new physics beyond the Standard Model (SM), unparticle, has been proposed, where a hidden conformal sector is coupled to the SM sector through higher dimensional operators. In this setup, we investigate unparticle physics at the photon collider, in particular, unparticle effects on the gamma gamma to gamma gamma process. Since this process occurs at loop level in the SM, the unparticle effects can be significant even if the cutoff scale is very high. In fact, we find that the unparticle effects cause sizable deviations from the SM results. The scaling dimension of the …

2008-04-03hep-phhep-th

Constraining unparticle physics from $CP$ violation in Cabibbo-favored decays of D mesons

According to the standard model, the Cabibbo-favored (CF) decays are $CP$ conserve at tree level. Observation of any finite $CP$ asymmetry can be received as a signal of new physics. In CF charm meson decays, $ D^0 \rightarrow K^- π^+ $ and $ D^+ \rightarrow K_s^0 π^+ $, the following experimental values for their $CP$ asymmetry are reported, respectively: ($0.3 \pm 0.7$) % and ($-0.41 \pm 0.09$) %. The value of the later can be attributed to the mixing of $ K^0 $ and $ \overline{K^0} $, however, its contribution is about ($-0.332 \pm 0.006 $) %. In this paper, we use these experimental result…

2017-05-17hep-ph

Colored Unparticles

We examine a scenario where the new physics at the LHC includes an approximate conformal field theory, where some of the degrees of freedom (aka "unparticles") carry a color charge. We present a simple argument showing that the production cross section for scalar unparticles mediated by a gauge interaction is given by (2-d) times the standard particle expression, where d is the scaling dimension of the unparticle field. We explicitly check that this is indeed the case, which involves non trivial cancellations between different Feynman diagrams, for the process q qbar to scalar unparticles.

2007-08-01hep-ph

Constraining Unparticles from Top Physics at TeVatron

We study and analyze the recent observations of the top pair production $σ(p\bar p\to t \bar t)$ at TeVatron through flavor conserving and flavor violating channels ${\it via}$ vector and tensor unparticles. The unparticle sector is considered with the possibility of being a color singlet or octet. The modified unparticle propagator is used to investigate the contribution of these unparticles to the observed $A_{FB}^{t\bar t}$ (forward backward asymmetry in top pair production) and the spin correlation at TeVatron. We have also studied the impact of the flavor violating couplings of unparticle…

2012-11-27hep-ph

Unparticles in Gluodynamics

The virtual effects of unparticle physics on the two-gluon jets production are explored for CERN LHC. It is found that depending on the scale dimension, unparticles can give rise to substantial enhancements in the transverse momentum and pseudo-rapidity distributions of hadronic cross sections, up to a factor of four-orders of magnitude.

2008-05-12hep-ph

Unraveling unparticles through violation of atomic parity and rare beauty

We put constraints on unparticle physics, specifically on the scale $Λ_\U$ and the scale dimension $d_\U$ of unparticle operators, using (i) measurements of atomic parity violation as well as (ii) branching ratio and CP asymmetry measurements in some rare non-leptonic B decay channels.

2007-10-08hep-ph

Collider Phenomenology of Unparticle Physics

Low energy phenomenology of the unparticle physics associated with an exact scale invariant sector possessing a non-trivial infrared fixed point at a higher energy scale is explored for both electron-positron and hadronic colliders. Feynman rules for a spin 0, 1 or 2 unparticle coupled to a variety of standard model gauge invariant operators that are relevant to many low energy processes involving either real emissions of unparticles or their virtual propagator effects are presented. Missing energy and/or recoil mass distributions of the unparticle in the associated production of unparticle to…

2007-07-01hep-phhep-th

Constraining Unparticle Physics with Cosmology and Astrophysics

It has recently been suggested that a scale invariant "unparticle" sector with a non-trivial infrared fixed point may couple to the Standard Model (SM) via higher dimensional operators. The weakness of such interactions hides the the unparticle phenomena at low energies. We demonstrate how cosmology and astrophysics can place significant bounds on the strength of unparticle-SM interactions. We also discuss the possibility of a having a non-negligible unparticle relic density today.

2007-09-21astro-phhep-ph

Flavors and Phases in Unparticle Physics

Inspired by the recent Georgi's unparticle proposal, we study the flavor structures of the standard model (SM) particles when they couple to unparticles. At a very high energy scale, we introduce $\BZ$ charges for the SM particles, which are universal for each generation and allow $\BZ$ fields to distinguish flavor generations. At the $Λ_{\UP}$ scale, $\BZ$ operators and charges are matched onto unparticle operators and charges, respectively. In this scenario, we find that tree flavor changing neutral currents (FCNCs) can be induced by the rediagonalizations of the SM fermions. As an illustrat…

2008-01-30hep-ph

Some Issues in a Gauge Model of Unparticles

We address in a recent gauge model of unparticles the issues that are important for consistency of a gauge theory, i.e., unitarity and Ward identity of physical amplitudes. We find that non-integrable singularities arise in physical quantities like cross section and decay rate from gauge interactions of unparticles. We also show that Ward identity is violated due to the lack of a dispersion relation for charged unparticles although the Ward-Takahashi identity for general Green functions is incorporated in the model. A previous observation that the unparticle's (with scaling dimension d) contri…

2008-12-16hep-ph

Unparticle physics effects in B_s mixing

We investigate unparticle effects in B_s mixing. In particular we discuss the possibility of reproducing the experimental result of ΔM_s, while having large effects on the mixing phase ϕ_s, which might be visible in current experiments.

2007-07-17hep-exhep-ph

Unparticle physics at hadron collider via dilepton production

The scale invariant unparticle physics recently proposed by Georgi could manifest at low energies as non integral number d_U of invisible particles. Unparticles if existing, could couple to the Standard Model fields and consequently affect the collider phenomenology. We consider the DY process to explore effects of the peculiar propagator of the scalar and tensor unparticle operators. To probe these effects at hadron collider one needs to go beyond LO in QCD and hence the quantitative impact of QCD corrections for unparticle physics at LHC is investigated. We present the K-factors at LHC. Incl…

2007-10-24hep-exhep-ph