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テラスケールにおける フレーバーの物理
テラスケールにおける フレーバーの物理 久野純治(名大理) 研究会「先端加速器LHCが切り拓くテラスケールの素粒子物理学」 ~ LHC・ATLAS実験の最新成果とテラスケール物理の夜明け ~ 2012/1/6-7 神戸大学 百年記念館 六甲ホール 1 研究目的 研究課題「テラスケール物理における世代構造の研究 」 LHC フレーバー の物理 テラスケール物理の解明とその背後にある物理探ることを 目的とする。 2 Contents of Talk • 現状分析 – ヒッグスボゾン – ミューオン (g-‐2) – Br(Bs→μ+μ-‐) • 進行中の研究 – 低エネルギーゲージ伝播模型 – 大きな超対称性の破れに感度がある物理量 – 陽子崩壊 3 ヒッグスボゾンの兆候(?) 2011/12/13 Talk by Fabiola GianoA Talk by Guido Tonelli 124-‐126GeVの質量のヒッグスボゾンの兆候。 軽いヒッグスボゾンを予言する超対称模型を示唆。 4 t ond, we see that the Higgs mass depends on Xt /MS as a quartic polynomial, and in general it has two peaks at p Xt /MS ⇡ ± 6, the “maximal mixing scenario” [10]. So we expect that mh = 125 GeV intersects this quartic in up to four places, leading to up to four preferred values for Xt /MS . Finally, we see that for fixed Xt /MS , the Higgs mass only increases logarithmically with MS itself. So we expect a mild lower bound on MS from mh = 125 GeV. Now let’s demonstrate these general points with detailed calculations using FeynHiggs. Shown in fig. 1 are contours of constant Higgs mass in the tan , Xt /MS plane, for mQ = mU = 2 TeV (where mQ and mU are the soft masses of the third-generation left-handed quark and right-handed up-type quark scalar fields). The shaded band corresponds to mh = 123 127 GeV, and S masses 2 the dashed lines indicate the same range of Higgs but with mt = 172 174 GeV. (The central value in all our30 plots will always be mh = 125 GeV at mt = 173.2 GeV.) From all this, we conclude that to be able to get mh25 ⇡ 125 GeV, we have Xmust t /Ms = ± 6 10 MSSM 5 0 -4 -2 0 ヒッグスボゾン質量 (ツリー+1ループ補正) Xt êMS 2 4 as it captures many of theFIG.qualitative 1. Contour plot of m features in the tan vs. Xthat /M plane.we The stops were set at m = m = 2 TeV, and the result is will see. We have characterized the onscale of upsuperpartonly weakly dependent the stop mass to ⇠ 5 TeV. The solid curve is m = 125 GeV with m = 173.2 GeV. The band 1/2 around the curve corresponds to m =123-127 GeV. Finally, ner masses with M ⌘ mthet̃1dashed mt̃2lines correspond . First, ( , ) to varying mwe from see 172-174.that decreasing tan always decreases the Higgs mass, inde3.0 t we partpendent of all the other parameters (keeping in mind that Xt /Ms = ± 6 2.5 that ndetan & tan1.5& 3.5for perturbativity). So we expect to find a (2) that 2.0 20 nd a lower bound on tan coming from the Higgs mass. SecSo this is an absolute lower bound on tan just from the Sec1.5 15 mass measurement. We also find that the Higgs Higgs M as ond, we see that the Higgs mass depends on Xt /MS as mass basically ceases to depend on tan for tan beyond ks at ⇠ 20. for the rest of thepolynomial, paper we will take tan = 30 ]. So 10 So a quartic and in 1.0general it has two peaks at p ic in for simplicity. alues Fixing , the Higgs mass is then athe function of X /M ⇡ ± 6, “maximal 5 Xtan 0.5 mixing scenario” [10]. So t S , the and M . Shown in fig. 2 are contours of constant m vs tself. M and X . We see that for that large=M we want M =M tan = 30 M ,m =h 2TeV = 125 GeV 0 we expect M = 125 0.0 intersects this quartic in -4 X -2 0 2 4 -6 -4 -2 0 2 4 6 up to four places, leading to up to four preferred values ⇡ 3, 1.7, 1.5, or 3.5 (3) h deX êM X @TeVD M 1 are for X . A-terms Finally, we see that for fixed Xt /MS , the tof/M /M FIG. Contour plot m inS the vs. Xand /M the plane. We1.also see that the smallest thetan SUSYmhand=the(123 127)GeV, mtof = 173.2GeV The stops were set at m be =are m = 2 TeV, result is m グレー: Draper et al FIG. 2. Contours constant m in the M vs.From X plane, scale can absolutely Higgs mass only logarithmically with M itself. only weakly dependent on the stop mass up to increases ⇠ 5 TeV. The nded S with tan = 30 and m = m . The solid/dashed lines and 5 Q S U t h h t MS @TeVD tanb S t h t S S h t Q S Q U U t t S S U The t t h Q S S U 波線:m = (172 solid curve is mh = 125 GeV with mt = 173.2 GeV. The t band 174)GeV h Q gray bands are as in fig. 1. U S t t ond, we see that the Higgs mass depends on Xt /MS as a quartic polynomial, and in general it has two peaks at p Xt /MS ⇡ ± 6, the “maximal mixing scenario” [10]. So we expect that mh = 125 GeV intersects this quartic in up to four places, leading to up to four preferred values for Xt /MS . Finally, we see that for fixed Xt /MS , the Higgs mass only increases logarithmically with MS itself. So we expect a mild lower bound on MS from mh = 125 GeV. Now let’s demonstrate these general points with detailed calculations using FeynHiggs. Shown in fig. 1 are contours of constant Higgs mass in the tan , Xt /MS plane, for mQ = mU = 2 TeV (where mQ and mU are the soft masses of the third-generation left-handed quark and right-handed up-type quark scalar fields). The shaded band corresponds to mh = 123 127 GeV, and S masses 2 the dashed lines indicate the same range of Higgs but with mt = 172 174 GeV. (The central value in all our30 plots will always be mh = 125 GeV at mt = 173.2 GeV.) From all this, we conclude that to be able to get mh25 ⇡ 125 GeV, we have Xmust t /Ms = ± 6 10 MSSM 5 0 -4 -2 0 ヒッグスボゾン質量 (ツリー+1ループ補正) Xt êMS 2 4 as it captures many of theFIG.qualitative 1. Contour plot of m features in the tan vs. Xthat /M plane.we set at m = m = 2o and SSM the result is Large tWe or have large S The stops or wereethe xtension f upsuperpartM will see. characterized scale ofTeV, only weakly dependent on the stop mass to ⇠ 5 TeV. The solid curve is m = 125 GeV with m = 173.2 GeV. The band 1/2 around the curve corresponds to m =123-127 GeV. Finally, ner masses with M ⌘ mthet̃1dashed mt̃2lines correspond . First, ( , ) to varying mwe from see 172-174.that decreasing tan always decreases the Higgs mass, inde3.0 t we partpendent of all the other parameters (keeping in mind that Xt /Ms = ± 6 2.5 that ndetan & tan1.5& 3.5for perturbativity). So we expect to find a (2) that 2.0 20 nd a lower bound on tan coming from the Higgs mass. SecSo this is an absolute lower bound on tan just from the Sec1.5 15 mass measurement. We also find that the Higgs Higgs M as ond, we see that the Higgs mass depends on Xt /MS as mass basically ceases to depend on tan for tan beyond ks at ⇠ 20. for the rest of thepolynomial, paper we will take tan = 30 ]. So 10 So a quartic and in 1.0general it has two peaks at p ic in for simplicity. alues Fixing , the Higgs mass is then athe function of X /M ⇡ ± 6, “maximal 5 Xtan 0.5 mixing scenario” [10]. So t S , the and M . Shown in fig. 2 are contours of constant m vs tself. M and X . We see that for that large=M we want M =M tan = 30 M ,m =h 2TeV = 125 GeV 0 we expect M = 125 0.0 intersects this quartic in -4 X -2 0 2 4 -6 -4 -2 0 2 4 6 up to four places, leading to up to four preferred values ⇡ 3, 1.7, 1.5, or 3.5 (3) h deX êM X @TeVD M 1 are for X . A-terms Finally, we see that for fixed Xt /MS , the tof/M /M FIG. Contour plot m inS the vs. Xand /M the plane. We1.also see that the smallest thetan SUSYmhand=the(123 127)GeV, mtof = 173.2GeV The stops were set at m be =are m = 2 TeV, result is m グレー: Draper et al FIG. 2. Contours constant m in the M vs.From X plane, scale can absolutely Higgs mass only logarithmically with M itself. only weakly dependent on the stop mass up to increases ⇠ 5 TeV. The nded S with tan = 30 and m = m . The solid/dashed lines and 6 A M Q S U t h h t MS @TeVD tanb S t h t S S h t Q S Q U U t t S S U The t t h Q S S U 波線:m = (172 solid curve is mh = 125 GeV with mt = 173.2 GeV. The t band 174)GeV h Q gray bands are as in fig. 1. U S t ared Evans, on Park for he DOE unk of PM is NSF-PHYtal Laws Iniws of Nature, s supported Y” scenarios s which can let us briefly For small FeynHiggs. o evolve the , computing persymmetry [40, 41], in which gauginos and higgsinos have masses well below MS and influence the running of . In this case, the running below MS is modified by the light superpartners, and the preferred scalar mass scale for a 125 GeV Higgs can be even larger [42–44]. Xtがゼロの時 135 1loop RGEで評価 130 125 mh @GeVD may be posn [37] where 120 115 FeynHiggsで評価 110 From Draper et al (1112.3068) 105 1 2 5 10 20 MS @TeVD 50 100 FIG. 6. Higgs mass as a function of MS , with Xt = 0. The 7 SUSY breaking models スキャンしたパラメータの99%が満たす上限値 From Arbey et al (1112.3028) 8 MSSMからの拡張 理由:自然さの問題、フレーバー問題、ミューオン (g-‐2) • Introduc[on of singlet (NMSSM) • Introduc[on of extra genera[on – Moroi et al – Endo et al • Introduc[on of new gauge interac[on – Endo et al 9 ミューオン (g-‐2) ミューオン(g-‐2)への様々な寄与: QED Hadronic vacuum Up to 5-‐loop leading polariza[on (HVP) Kinoshita et al Light-‐by-‐light scaeering (LbyL) Electroweak at two-‐loop level Beyond SM 実験値(BNK-‐E821) 10 ミューオン (g-‐2) ミューオン(g-‐2)への様々な寄与: QED Hadronic vacuum Up to 5-‐loop leading polariza[on (HVP) Kinoshita et al Light-‐by-‐light scaeering (LbyL) Electroweak at two-‐loop level Beyond SM 実験値(BNK-‐E821) Experimental value(BNK-‐E821) SMの予言は実験値から3σ強のズ レ (from Hagiwara et al) SMの予言の不定性:HVPとLbyLの 寄与 1111 標準模型を超える理論におけるミューオン (g-‐2) ミューオン(g-‐2)の有効演算子: MSSMは、2つヒッグス二重項を持つことから、比較的軽いwino, sleptonがあれば大きな補正が可能。 5 2 + Y m2µ ⇤aµ tan ⇥ 2 48⌅ M ) 9 ) Reference value: a(EW =SUSY 1.5 10a(EW = 1.5 10 9 µ (参照値)W/Zボゾンの寄与: µ ⇥ ⇥ 2 tan MSUSY = 3 10 9 10 200GeV Mwino Mgluino /3.4 , m CMSSMでは slepton > M gluino /3.9 (GUT rela[onより)なので, 軽いwino, sleptonは難しい(?) 12 Hadronic vacuum polariza[on (HVP) • R比からのHVPの評価 R比 • HVPの最新の評価 (leading order): aµ |HVP,LO = (694.91 ± 3.65exp ± 2.10rad ) (692.3 ± 4.2) 10 (690.75 ± 4.72) e+ e hardrons 10 10 (Hagiwara et al, 11) 10 10 (Davier al, 10) 10 e+ e (Jegerlehner and Szafran, 11) IRS + hardrons 13 Light-‐by-‐light scaeering(LbyL) • LbyLの寄与の評価は“模型”に依存。 • Prades, Rafael, Vainshteinが複数の模型の評価とその誤差を比較 検討。 aµ |LBL = (10.5 ± 2.6) • 格子ゲージ理論による評価? 10 10 14 ミューオン (g-‐2)測定の将来計画 BNL-E821 Fermilab J-PARC pµ 3.09 GeV/c 0.3 GeV/c γ 29.3 3 storage field B = 1.45 T 3T focusing field Electric Quadrupole None # of detected µ+ decays 5.0 × 109 1.8 × 1011 1.5 × 1012 # of detected µ− decays 3.6 × 109 − − achieved/expected precision (stat) 0.46 ppm 0.1 ppm 0.11 ppm (From Leeer of Intent: New Measurement of Muon Anomalous Magne[c Moment g-‐2 and Electric Dipole Moment at J-‐PARC) TABLE II: Key parameters of the previous and proposed experiments relevant for the statistical precision factors which distort positron time spectrum (wiggle plot) in Eq. 16, and may be origins of systematic uncertainty. " ! t × [1 − A cos(ωa × t + δ0 )], N(t) = N0 · exp − γτ (16) possible factors of wiggle distortion are listed below: 1. Energy dependent efficiency of positron detection, as well as energy resolution, 2. Time dependent efficiency of positron detection: 15 Br(Bs→μ+μ-‐) MSSMの重いヒッグスボゾンに感度がある。 16 Br(Bs + -‐ →μ μ ) 標準模型の予言:Br(Bs→μ+μ-‐) =(3.2±0.2)×10-‐9 実験値:Br(Bs→μ+μ-‐) <1.3×10-‐8 (LHCb) ,1.9×10-‐8 (CMS) ,5.1×10-‐8 (D0) Br(Bs→μ+μ-‐) =(1.8+1.1-‐0.9)×10-‐8 (CDF) From Hooper and Kelso 17 低エネルギーゲージ伝播模型 グラビティーノ質量M3/2<16eVを実現する模型: 准安定真空 W = M)¯ µ2 S + ( S K = |S| + | ¯ | + | | 2 2 2 |S|4 4 2 超対称粒子の質量(N:メッセンジャーの数) を小さくすると真空が不安定になる。 ¯ /µ(= /µ) 18 低エネルギーゲージ伝播模型 超対称性の破れ:IYIT模型 超対称性を破る真空の量子的、熱的安定性からの制限 (メッセンジャーはSU(5)の10次元表現) From JH, Nagai, Sugiyama,Yanagida メッセンジャークォーク・レプトンのSとの結合を変えるとさら 19 にスクォークを重くできる(軽いスレプトンを予言)。 重い超対称粒子に感度ある観測量 近似的大域的対称性の破れ • CP対称性の破れ (CKM行列) 電気双極子能率(EDM) • レプトンフレーバー対称性の破れ (ニュート リノ振動) 荷電レプトンフレーバー数非保存過程(cLFV) 20 MSSMにおけるcLFV (m2l̃ )ij = (ml m†l )ij + (m̃2l )ij スレプトン 質量行列 レプトン 質量行列 (i, j = 1 3) スレプトンの超対 称性を破る質量 項の寄与 • SUSYフレーバー問題 Br(µ ⇥ e⇥) Br(µ ⇥ e⇥) 4⇤ < 2.4 m 4⇤ W mSU SY 10 12 ⇥4 sin2 ẽµ̃ ⇤ m2l̃ m2SU SY ⌅2 (MEG) 2 1) Universal scalar mass hypothesis: m2 m l̃ l̃ 2 2) Alignment hypothesis: sin ẽµ̃ 1 mW 3) Decoupling hypothesis: mSU SY cLFVの研究により超対称性の破れの起源や超対称標準模型を越える相互 21 作用を探ることができる。 section IV), it turns out that the required right handed paramet neutrino masses are close to the GUT scale, which fits our scheme naturally. II GUTsや右巻ニュートリノの相互作用を起源とするcLFV MPlanck MX MGU T M Rk MSUSY ! LFVを持つ In the スレプトン tribution 質量項 SO(10) SO(10) SU(5)RN MSSMRN MSSM SM to under rameters 右巻ニュートリノの湯川にある混合行列がCKMかPMNSか notation of the sl FIG. 1: Schematic picture of the energy scales involved in the model. tries are soft scal Before proceeding in to next section where we detail universa the various lepton flavour violating terms generated in slepton s 超対称性 破れの起源 M2"˜ = ! m2"˜(1 + δLL ) + Ye Ye† vd2 + O(g 2 ) vd (A†e 2 2 vd (Ae − Ye µ tan β) + δ m̂ m (1 + RL ˜ 22 From Calibbi et a"˜l. " Decoupling hypothesisにおけるHiggs media[on SUSY粒子の質量がO(1-‐10)TeV以上の場合SUSY粒子の 1ループの寄与は無視できる一方で、Higgs media[onの 寄与により観測可能になり得る。 Contour plot of BR(µAl → eAl) / BR(µ → eγ), tan β vs MSUSY /mA0 including Higgs- and gaugino-mediated contributions. ∼ (10 − 50) and tan β > ∼ 10, both Higgs- and gaugino-mediated diagrams to those processes in different way and we could give constraints MSUSY /mA0 from BR(µAl → eAl)/BR(µ → eγ) . A0 , t, b nclusions and discussion er, we reevaluated µ-e transition processes induced by non-holomorphic Yukawa ns in the MSSM. We discussed correlation among branching ratios for µ → eγ, and µ-e conversion in nuclei in the MSSM, including both the gauginoFrom JH, by Sugiyama, Yang, Yamanaka. 0 including our plot of contributions BR(µAl → eAl) / BR(µ → eγ),Ittan β vs M /m -mediated to the processes. was assumed in this letter that 23 超対称性の破れ 超対称粒子:超対称性の自発的対称性の破れにより質量を獲得 超対称標準模型における超対称性の破れ • ゲージーノの質量項: • ヒグシーノの質量項: Ma a a (a = 1, 2, 3) µ H̃u H̃d • スクォーク、スレプトン、ヒッグスボゾンの質量項 (m2f˜)ij f˜i† f˜j (f˜ = q̃L , ũR , d˜R , ˜lL , ẽR , i, j = 1, 2, 3) • ヒッグスボゾンの混合質量項(B項) Bµ Hu Hd • スクォーク、スレプトンの混合質量項(A項) (mf Af )ij f˜Li f˜Ri (f = u, d, e) 24 超対称性の破れ 超対称粒子:超対称性の自発的対称性の破れにより質量を獲得 超対称標準模型における超対称性の破れ • ゲージーノの質量項: • ヒグシーノの質量項: Ma a a (a = 1, 2, 3) µ H̃u H̃d • スクォーク、スレプトン、ヒッグスボゾンの質量項 (m2f˜)ij f˜i† f˜j (f˜ = q̃L , ũR , d˜R , ˜lL , ẽR , i, j = 1, 2, 3) • ヒッグスボゾンの混合質量項(B項) Bµ Hu Hd 一般に複素数で、そ の位相はCPの破れの 起源となる。 • スクォーク、スレプトンの混合質量項(A項) (mf Af )ij f˜Li f˜Ri (f = u, d, e) 25 CMSSM(MSUGRA)におけるEDM CMSSMではSUSYの破れの項がGUTスケールで与えられる。 Af = A0 Ma = M1/2 (a = 1, 2, 3) 物理的なCP対称性の破れの位相で現れる。 B = ang(M1/2 B ) A (f = u, d, e) = ang(M1/2 A0 ) 超対称粒子の1ループダイアグラムにより、EDMおよびCEDMが 生成される。 • 電子EDMからの制限 • 中性子EDMからの制限 26 (Pospelov&Ritz) CMSSM(MSUGRA)におけるEDM CMSSMではSUSYの破れの項がGUTスケールで与えられる。 Af = A0 Ma = M1/2 (a = 1, 2, 3) 物理的なCP対称性の破れの位相で現れる。 B = ang(M1/2 B ) A (f = u, d, e) = ang(M1/2 A0 ) 超対称粒子の1ループダイアグラムにより、EDMおよびCEDMが 生成される。 SUSY CP問題はどこまで問題なのか? 中性子EDMの評価:QCD和則 保守的制限をどこまで緩くできるのか? • 電子EDMからの制限 • 中性子EDMからの制限 27 (Pospelov&Ritz) 様々なEDMへの寄与 28 様々なEDMへの寄与 有効理論の立場で EDMの理論の整理 29 j i 2 1 2 µ 1+ √ g5 VijC (eCj · X µ µ )γ Qi + h.c.. + √ g5 V · X )γ Qi + h.c.. (e µ ij 2 j 2 大統一模型における陽子崩壊 (10) This interaction leads to the following baryon-number violating operators, This interaction leads to the following baryon-number violating operators, which w TeVスケールの全貌がわかることで、よりよい推測ができる。 0 + 0 π + e , contribute to p → ontribute to p → π e , ・ Xボゾンによる陽子崩壊。 2 g52 giϕ iϕ1 Lfef f = =ARAR2 e 52 1e× × Lef MXMX 2 α C γ β C α)β (uCβ)γ (e C γ (1 + |V |2 )(dC )α )α (u (uLCR)β)(u (eR(u))CL )γ(11) #αβγ#αβγ ((dCL((d (eL ) + (1ud+ |Vud (u (eR )) R | )(d L )L ) L )R (uR )R (uRL)) + 36 10 16 MX = 1 10 GeV 6 M=10anomalous GeV where renormalization factor from from the dimensions to theseto whereARARis isthethe renormalization factor the anomalous dimensions M=104 GeV Extra maeer の 10 導入は、高エネ (SD) The renormalization factor A has the short-distance contribution (A ) (A and(SD) ) R A has the short-distance contribution α =20 R The renormalization factor R ルギーのゲー R (LD) (SD) =15 (LD) (SD) he long-distance contribution α(A AR at one-loop levelジ結合定数を is given as R (A). the long-distance contribution ). A at one-loop level is given as 34 R R 10 ! " 4 ! " 3 大きくする。 α =10 3b3 " 4 ! ! α (m ) α (m ) 2b2 " 3 τ (p π 0 e+ ) (years) perators. operators. 2 35 M=10 GeV -1 5 -1 5 -1 5 (SD) AR 33 10 0 0.5 = (SD) AR 1 3 Z α3 (mZ ) = α5 α5 1.5 2 2.5 #(5+5 * ) +3 #(10+10* ) 3 2 3b 3 Z α (m ) α5 2 Z α5 3.5 2b2 (12) 4 From JH. 30 まとめ • 124-‐126GeVのヒッグスボゾンの存在は、超対称模 型の模型に対して、 重いストップ/大きなAt/MSSM からの拡張を意味する。 • 軽い超対称粒子を意味するミューオンg-‐2の結果と 124-‐126GeVのヒッグスボゾンの間に緊張がある。 • Br(Bs→μ+μ-‐) は、MSSMの重いヒッグスボゾンに高い 感度があり、またAtが大きいのであれば、SMから大 きなズレが期待される。 31 まとめ • M3/2<16eVを実現する低エネルギーゲージ伝搬模型 はどこまでスクォーク重くできるか。 • 中性子のEDMのQCD和則の評価における不定性は どれくらいか。 • EDMの系統的評価 • 陽子崩壊の高次補正(?) 32