随着生活水平的提高，口腔健康教育宣传的开展，越来越多的人意识到洁牙的重要性。目前，临床上大多数医院采用超声波洁牙，但它工作时所发出刺耳的声音，会给患者造成一种心理上的恐惧感。激光清洗技术作为一项新兴清洗技术，已成为传统清洗方法的补充和延伸，因其固有的优点，而在工农业生产、科研、医疗、国防建设等方面得到广泛的应用，激光洁牙设备将成为现代牙科必不可少的工具。与超声波洁牙等技术相比，激光洁牙属于非机械接触，不存在超声波洁牙所具有的振动噪声，不易损伤牙齿表面釉质，不损伤周边组织。按现有的牙科医疗器械，患者是无法了解自己口腔内牙齿的受损程度，是否接受治疗则完全交由医疗人员决定，而且现有牙科医疗器械还无法...As life’s quality improved, oral health propagandized, the importance of teeth cleaning is attracted more and more people’s attention. In clinic, ultrasonic wave is used to clean the tooth, but the noise from the ultrasonic wave would lead a dread to the patients. As a new cleaning technology ， Laser cleaning play the role of complementarity and extendability of traditional cleaning. Due to...学位：工学硕士院系专业：物理与机电工程学院机电工程系_测试计量技术及仪器学号：20032900

陈春华

Xiamen University Institutional Repository

Research of Image Acquisition and Data Management System in Tooth Cleaning Laser Machine

Guadagnoli, D

CERN Document Server

CP violation in models with Minimal Flavour Violation

We shortly describe the framework of Minimal Flavour Violation (MFV), emphasizing that it does not necessarily imply that CP violation be minimal as well. We then reconsider the correlation between the amount of CP violation in the K- and Bd-systems within the Standard Model, quantified by �K vs. sin 2β. We show that, in view of recent improvements in the �K theoretical formula, this

consistency test is in fact less than perfect. Finally, we briefly outline how a solution to a confirmed discrepancy may be found without going beyond MFV

Guadagnoli, D.

Scientific Open-access Literature Archive and Repository

DOI 10.1393/ncc/i2009-10449-9Colloquia: IFAE 2009IL NUOVO CIMENTO Vol. 32 C, N. 3-4 Maggio-Agosto 2009CP violation in models with Minimal Flavour ViolationD. GuadagnoliPhysik-Department, Technische Universita¨t Mu¨nchen - D-85748 Garching, GermanyCERN, Theory Division - CH-1211, Geneva 23, Switzerland(ricevuto il 19 Settembre 2009; pubblicato online il 10 Novembre 2009)Summary. — We shortly describe the framework of Minimal Flavour Violation(MFV), emphasizing that it does not necessarily imply that CP violation be minimalas well. We then reconsider the correlation between the amount of CP violationin the K- and Bd-systems within the Standard Model, quantified by K vs. sin 2β.We show that, in view of recent improvements in the K theoretical formula, thisconsistency test is in fact less than perfect. Finally, we briefly outline how a solutionto a confirmed discrepancy may be found without going beyond MFV.PACS 12.15.Ji – Applications of electroweak models to specific processes.PACS 14.40.Aq – π, K, and η mesons.PACS 14.40.Nd – Bottom mesons.1. – IntroductionAa is well known, within the Standard Model (SM) all the flavour and CP viola-tion originates from the “misalignment” between the up-quark and down-quark Yukawacouplings Yu, Yd when they are diagonalized via chiral unitary transformations on thequark fields. These transformations leave a physical remnant in that the CKM matrixappears in W -quark-quark interactions, but not on those with the Z. As a consequence,neutral-current interactions can change flavour only at the loop level. Hence, within theSM, flavour-changing neutral current effects are generally and naturally small, due to theloop suppression, and to the fact that they must be proportional to quark squared-massdifferences. In fact, the misalignment between the transformations on uL and dL be-comes immaterial if either u- or d-quarks are degenerate. This mechanism of flavour andCP violation leads to highly non-generic patterns of experimental predictions, that havebeen widely tested, with no established discrepancy to date. One can make this piece ofinformation useful in the construction of SM extensions by addressing the question: Cana SM-like mechanism of near-flavour-conservation be embedded in a generic, Fermi-scaleextension of the SM?The crucial observation [1] is that, in the absence of the Yukawa interactions, the SMis invariant under an SU(3)5 group of global, chiral transformations, called the flavourc© Societa` Italiana di Fisica 179180 D. GUADAGNOLIgroup. One can then postulate (“Minimal Flavour Violation principle” [2]) that the SMYukawas are the only source of flavour violation even beyond the SM. This implies thatany new, potential source M of flavour violation must inherit from the SM Yukawas,i.e. effectively be a function M(Yu, Yd, . . .), the functional form being fixed by treatingthe Yukawas as spurions of the flavour group. If one thinks of the functional form as apolynomial expansion in the Yukawas, the coefficients will in general not be fixed by theMFV principle itself, and may be free complex numbers where applicable. This impliesthat, within MFV, CP violation is actually not necessarily minimal, i.e. is not describedby exclusively the CKM phase.It is clear that MFV is not the easiest scenario where to search for non-SM effects.Recent phenomenological analyses within the MSSM, adopting the MFV definition of [2],can be found in [3] and show that resolving discrepancies with respect to the sheer SMoften requires high accuracies. On the other hand, the fact that data seem to point toMFV would induce to take MFV at the very least as a good approximation to reality. Arealistic strategy seems then to look for instances where MFV is distinguishable from theplain SM. In the next section, I will present one such instance, where new physics maybe of MFV type and, nonetheless, could be already manifesting itself. Reaching firmerconclusions depends, as often in MFV, on improvements in the control of the theoreticalinput. The main point is that the required improvement may well be feasible in this case.2. – CP violation in the K- vs. Bd-systemsWithin the K-meson system, indirect CP violation is described by the parameter K ,which can be calculated with the following theoretical formula [4]:(1) K = eiφ sinφ(Im(MK12)ΔMK+ ξ),with ξ = ImA0/ReA0, A0 the 0-isospin amplitude in K → ππ decays, MK12 =〈K|HfullΔF=2|K〉 and ΔMK the K − K system mass difference. The phase φ is mea-sured to be φ = (43.5 ± 0.7)◦ [5]. In contrast with the K formula used in basicallyall phenomenological applications, eq. (1) takes into account φ = π/4 and ξ = 0. Inorder to make the impact of these two corrections transparent, we will parameterize themthrough an overall factor κ in K :(2) κ =√2 sinφκ,with κ parameterizing the effect of ξ = 0 through κ = 1 + ξ√2|K | ≡ 1 + Δ, where Δhas been introduced for later convenience. It turns out that both ξ = 0 and φ < π/4imply suppression effects in K relative to the approximate formula, with the correctionfrom ξ = 0 being of O(5%) by itself. For the total correction factor one finds, within theSM [4](3) κ = 0.92± 0.02.Hence the like sign of the two corrections in eq. (2) turns out to build up a −8% totalshift with respect to the approximate K formula.Before discussing the phenomenological impact of κ, it is worth shortly describinghow ξ can actually be estimated. As discussed in detail in [4,6], a direct calculation of ξ isCP VIOLATION IN MODELS WITH MINIMAL FLAVOUR VIOLATION 181Fig. 1. – (Colour on-line) |SMK | vs. sin 2β with only BˆK errors included. BˆK ∈{0.65, 0.70, 0.75, 0.80} ± 3% are shown as blue areas (darker to lighter). Vertical green areasdisplay sin 2β ∈ {0.681, 0.75, 0.88} ± 3.7% (from [4]).subject at present to very large hadronic uncertainties, as no consensus exists on the valueof the non-perturbative parameter B6, describing QCD-penguin operators, that dominateξ. Much more reliable is the indirect strategy [7] of estimating ξ from the experimentalvalue of ′/, through the relation ′/ = −ωΔ(1− Ω). Here ω = ReA2/ReA0 = 0.045the well-known ΔI = 1/2 rule, and Ω the ratio between EW-penguin and QCD-penguincontributions to ′/. Ω represents the main theoretical input in this procedure, but isin much better theoretical control than ξ. The analysis by [8] finds Ω = 0.4± 0.1 withinthe SM and this 25% error translates into Δ = −0.061 ± 0.014, whence one arrives atthe estimate (3).It should be noted that Ω is in general sensitive to non-SM contributions, becauseEW penguins are. However, a shift in Ω due to non-SM EW-penguin contributionscan be parameterized most generally [6], and Δ be accordingly estimated through ageneralization of the above-mentioned strategy. It turns out that realistic EW-penguinshifts below 50% of the SM contribution typically lead to Δ  −0.04 (see [6] for thedetails). This speaks for the robustness of the estimate (3) beyond the SM.Let us now turn to the consequences of a −8% suppression effect on SMK . Once therest of the input is fixed, the formula for SMK allows to predict sin 2β, that measures CPviolation in the Bd system. In fact, it is easy to see that the top-top contribution toSMK , amounting to roughly 75% of the SM prediction, is directly proportional to sin 2β.It obviously follows that, being the K experimental result fixed, a suppression from κimplies a larger predicted value for sin 2β. The situation is quantitatively illustratedin fig. 1, reporting the |SMK | prediction as a function of sin 2β for various values of theBˆK parameter (see figure caption for more details). Since a realistic range for BˆK isBˆK = 0.72 ± 5% (see, e.g., the unquenched result of [9], and the caption of their fig. 4for more details on the error components), fig. 1 points, for sin 2β = sin 2βJ/ψKs , to acentral value for |SMK | about 20% below experiment. Even if fig. 1 does not include allcomponents of the K error, we believe the above issue warrants further attention. Inparticular, one can investigate whether the value of sin 2β required to accommodate |K |within the SM may be too high with respect to the sin 2β determination from Bd physics,as pointed out in [10] for κ = 1. As emphasized in [4], the above could more generallyentail the presence of a new phase either dominantly in the Bd system, or respectively in182 D. GUADAGNOLIthe K system, or, alternatively, of two smaller phases in both systems, defining in turnthree new-physics scenarios. The vertical sin 2β ranges in fig. 1, with a relative errorchosen at 3.7% as in the sin 2βψKs case, define the scenarios in question. Addressingthe significance of either scenario crucially depends on the errors associated with thetheoretical input entering the SMK formula.Indeed, let us now focus on the first scenario, where no new phase is assumed in the Bdsystem, so that sin 2β = sin 2βψKs . In this case, varying all the K input with Gaussiandistributions around their respective determinations (see input table in [6]), one obtains|SMK | = (1.78± 0.25)× 10−3 [6], to be compared with |SMK | = (2.229± 0.012)× 10−3 [5].In this case, the most straightforward kind of new physics that may fix K is a shift inthe ΔF = 2 loop function, which is of MFV type [11]. In particular, barring non-SMoperators mediating meson mixings, this shift would be universal, i.e. proportionallyaffect also Bd and Bs mass differences Δmd,s. In particular, it would cancel in theirratio Δmd/Δms, the combination actually relevant in Unitarity Triangle fits.Conversely, in the third scenario [10], one assumes new physics to mostly affect thesin 2β determination, with K being essentially SM-like. Since in this case one hassin 2βJ/ψKs = sin 2(β + φNP), with φNP a non-SM phase, it is clear that β cannot beaccessed from the J/ψKs mode alone. One possible strategy is to determine β from theK , Δmd and ΔMs constraints. With this procedure, we get sin 2β = 0.88+0.11−0.12 [4], tobe compared with the (2007) HFAG average sin 2β = 0.681 ± 0.025 [12]. One gathersthat the φNP phase, negative, may be correlated, even in size, with the (again negative)new phase in Bs hinted at by Fermilab [13]. In spite of the presence of a new phase, thenon-SM physics resposible for it does not need to be beyond MFV. However, the answeris highly model-dependent in this case.3. – ConclusionsThe K vs. sin 2β correlation is a fundamental consistency test of SM CP violation, infact the only one available at present. Our analysis shows that an accurate SM formulafor K implies a −8% shift in its central value. Looking at the entailed prediction forsin 2β, the above shift hints at a tension with respect to sin 2βJ/ψKs . Reaching firmerconclusions about this tension requires improvement in the SMK theoretical input. Togive an idea, the dominant (75%) top-top contribution to K leads to the following errorbudget (see [6]):(4)δ|SMK ||SMK |≈ 5%BˆK ⊕ 11%|Vcb|4 ⊕ 8%R2t ≈ 15%.The Rt error should drastically improve after a precise γ determination at LHCb andsome room for improvement can be expected also on BˆK from lattice QCD. Thereforethe fate of the bulk of the error in eq. (4) is arguably in the hands of |Vcb|.REFERENCES[1] Chivukula R. S. and Georgi H., Phys. Lett. B, 188 (1987) 99.[2] D’Ambrosio G., Giudice G. F., Isidori G. and Strumia A., Nucl. Phys. B, 645 (2002)155.[3] Isidori G., Mescia F., Paradisi P., Smith C. and Trine S., JHEP, 0608 (2006) 064;Altmannshofer W., Buras A. J. and Guadagnoli D., JHEP, 0711 (2007) 065.CP VIOLATION IN MODELS WITH MINIMAL FLAVOUR VIOLATION 183[4] Buras A. J. and Guadagnoli D., Phys. Rev. D, 78 (2008) 033005.[5] Amsler C. et al. (Particle Data Group), Phys. Lett. B, 667 (2008) 1.[6] Buras A. J. and Guadagnoli D., arXiv:0901.2056 [hep-ph].[7] Anikeev K. et al., arXiv:hep-ph/0201071; Andriyash E. A., Ovanesyan G. G. andVysotsky M. I., Phys. Lett. B, 599 (2004) 253; Phys. Atom. Nucl., 69 (2006) 286.[8] Buras A. J. and Jamin M., JHEP, 0401 (2004) 048.[9] Antonio D. J. et al. (RBC Collaboration and UKQCD Collaboration), Phys. Rev.Lett., 100 (2008) 032001.[10] Lunghi E. and Soni A., Phys. Lett. B, 666 (2008) 162.[11] Buras A. J., Gambino P., Gorbahn M., Jager S. and Silvestrini L., Phys. Lett. B,500 (2001) 161.[12] Barberio E. et al. (Heavy Flavor Averaging Group (HFAG) Collaboration),arXiv:0704.3575 [hep-ex].[13] Aaltonen T. et al. (CDF Collaboration), Phys. Rev. Lett., 100 (2008) 161802;Abazov V. M. et al. (D0 Collaboration), Phys. Rev. Lett., 101 (2008) 241801.

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Research of Image Acquisition and Data Management System in Tooth Cleaning Laser Machine

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