Abstract
We present standard model (SM) estimates for exclusive c → uγ processes in heavy quark and hybrid frameworks. Measured branching ratios \( \mathrm{\mathcal{B}}\left({D}^0\to\ \left(\phi, {\overline{K}}^{\ast 0}\right)\gamma \right) \) are at or somewhat exceeding the upper range of the SM and suggest slow convergence of the 1/m D , α s -expansion. Model-independent constraints on |ΔC| = | ΔU | = 1 dipole operators from ℬ(D 0 → ρ 0 γ) data are obtained. Predictions and implications for leptoquark models are worked out. While branching ratios are SM-like CP asymmetries ≲ 10% can be induced. In SUSY deviations from the SM can be even larger with CP asymmetries of O(0.1). If Λ c -baryons are produced polarized, such as at the Z-pole, an angular asymmetry in Λ c → pγ decays can be studied that is sensitive to chirality-flipped contributions.
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J.L. Hewett et al., The discovery potential of a super B factory, hep-ph/0503261 [INSPIRE].
T. Aushev et al., Physics at super B factory, arXiv:1002.5012 [INSPIRE].
C. Greub, T. Hurth, M. Misiak and D. Wyler, The c → uγ contribution to weak radiative charm decay, Phys. Lett. B 382 (1996) 415 [hep-ph/9603417] [INSPIRE].
G. Isidori and J.F. Kamenik, Shedding light on CP-violation in the charm system via D→Vγ decays, Phys. Rev. Lett. 109(2012)171801 [arXiv:1205.3164] [INSPIRE].
S. Fajfer and P. Singer, Long distance c → uγ effects in weak radiative decays of D mesons, Phys. Rev. D 56 (1997) 4302 [hep-ph/9705327] [INSPIRE].
S. Fajfer, S. Prelovsek and P. Singer, Long distance contributions in D → V γ decays, Eur. Phys. J. C 6 (1999) 471 [hep-ph/9801279] [INSPIRE].
S. Fajfer, S. Prelovsek, P. Singer and D. Wyler, A possible arena for searching new physics: the Γ(D 0 → ρ 0 γ)/Γ(D 0 → ωγ) ratio, Phys. Lett. B 487 (2000) 81 [hep-ph/0006054] [INSPIRE].
G. Burdman, E. Golowich, J.L. Hewett and S. Pakvasa, Radiative weak decays of charm mesons, Phys. Rev. D 52 (1995) 6383 [hep-ph/9502329] [INSPIRE].
A. Khodjamirian, G. Stoll and D. Wyler, Calculation of long distance effects in exclusive weak radiative decays of B meson, Phys. Lett. B 358 (1995) 129 [hep-ph/9506242] [INSPIRE].
S. Fajfer, S. Prelovsek and P. Singer, FCNC transitions c → uγ and s → dγ in B c → B * u γ and B s → B * d γ decays, Phys. Rev. D 59 (1999) 114003 [Erratum ibid. D 64 (2001) 099903] [hep-ph/9901252] [INSPIRE].
S. de Boer and G. Hiller, Flavor and new physics opportunities with rare charm decays into leptons, Phys. Rev. D 93 (2016) 074001 [arXiv:1510.00311] [INSPIRE].
A. Paul, I.I. Bigi and S. Recksiegel, On D → X u ℓ + ℓ − within the Standard Model and frameworks like the littlest Higgs model with T parity, Phys. Rev. D 83 (2011) 114006 [arXiv:1101.6053] [INSPIRE].
S. Fajfer, S. Prelovsek and P. Singer, Rare charm meson decays D → P ℓ + ℓ − and c → uℓ + ℓ − in SM and MSSM, Phys. Rev. D 64 (2001) 114009 [hep-ph/0106333] [INSPIRE].
S.W. Bosch and G. Buchalla, The radiative decays B → V γ at next-to-leading order in QCD, Nucl. Phys. B 621 (2002) 459 [hep-ph/0106081] [INSPIRE].
Belle collaboration, A. Abdesselam et al., Observation of D 0 → ρ 0 γ and search for CP violation in radiative charm decays, Phys. Rev. Lett. 118 (2017) 051801 [arXiv:1603.03257] [INSPIRE].
LHCb collaboration, Measurement of the difference of time-integrated CP asymmetries in D 0 → K − K + and D 0 → π − π + decays, Phys. Rev. Lett. 116 (2016) 191601 [arXiv:1602.03160] [INSPIRE].
S. de Boer, B. Müller and D. Seidel, Higher-order Wilson coefficients for c → u transitions in the Standard Model, JHEP 08 (2016) 091 [arXiv:1606.05521] [INSPIRE].
Z.-G. Zhao et al., Report of Snowmass 2001 working group E2: electron-positron colliders from the φ to the Z, eConf C 010630 (2001) E2001 [hep-ex/0201047] [INSPIRE].
D. d’Enterria, Physics case of FCC-ee, Frascati Phys. Ser. 61 (2016) 17 [arXiv:1601.06640] [INSPIRE].
A. Ali and A.Y. Parkhomenko, Branching ratios for B → K ∗ γ and B → ργ decays in next-to-leading order in the large energy effective theory, Eur. Phys. J. C 23 (2002) 89 [hep-ph/0105302] [INSPIRE].
M. Beneke, T. Feldmann and D. Seidel, Systematic approach to exclusive B → V ℓ + ℓ − , V γ decays, Nucl. Phys. B 612 (2001) 25 [hep-ph/0106067] [INSPIRE].
M. Beneke, T. Feldmann and D. Seidel, Exclusive radiative and electroweak b → d and b → s penguin decays at NLO, Eur. Phys. J. C 41 (2005) 173 [hep-ph/0412400] [INSPIRE].
Belle collaboration, A. Heller et al., Search for B + → ℓ + ν ℓ γ decays with hadronic tagging using the full Belle data sample, Phys. Rev. D 91 (2015) 112009 [arXiv:1504.05831] [INSPIRE].
G.P. Korchemsky, D. Pirjol and T.-M. Yan, Radiative leptonic decays of B mesons in QCD, Phys. Rev. D 61 (2000) 114510 [hep-ph/9911427] [INSPIRE].
P. Ball and E. Kou, B → γeν transitions from QCD sum rules on the light cone, JHEP 04 (2003) 029 [hep-ph/0301135] [INSPIRE].
A. Khodjamirian, T. Mannel and N. Offen, B-meson distribution amplitude from the B → π form-factor, Phys. Lett. B 620 (2005) 52 [hep-ph/0504091] [INSPIRE].
V. Pilipp, Matching of λ B onto HQET, hep-ph/0703180 [INSPIRE].
S.W. Bosch and G. Buchalla, Constraining the unitarity triangle with B → V γ, JHEP 01 (2005) 035 [hep-ph/0408231] [INSPIRE].
P. Ball, G.W. Jones and R. Zwicky, B → V γ beyond QCD factorisation, Phys. Rev. D 75 (2007) 054004 [hep-ph/0612081] [INSPIRE].
A.L. Kagan and M. Neubert, Isospin breaking in B → K ∗ γ decays, Phys. Lett. B 539 (2002) 227 [hep-ph/0110078] [INSPIRE].
B. Grinstein, Y. Grossman, Z. Ligeti and D. Pirjol, The photon polarization in B → Xγ in the Standard Model, Phys. Rev. D 71 (2005) 011504 [hep-ph/0412019] [INSPIRE].
B. Grinstein and D. Pirjol, Long distance effects in B → V γ radiative weak decays, Phys. Rev. D 62 (2000) 093002 [hep-ph/0002216] [INSPIRE].
M. Dimou, J. Lyon and R. Zwicky, Exclusive chromomagnetism in heavy-to-light FCNCs, Phys. Rev. D 87 (2013) 074008 [arXiv:1212.2242] [INSPIRE].
M. Bauer, B. Stech and M. Wirbel, Exclusive nonleptonic decays of D, D s and B mesons, Z. Phys. C 34 (1987) 103 [INSPIRE].
CLEO collaboration, D.M. Asner et al., Radiative decay modes of the D 0 meson, Phys. Rev. D 58 (1998) 092001 [hep-ex/9803022] [INSPIRE].
Particle Data Group collaboration, C. Patrignani et al., Review of particle physics, Chin. Phys. C 40 (2016) 100001 [INSPIRE].
A.J. Buras, QCD factors a 1 and a 2 beyond leading logarithms versus factorization in nonleptonic heavy meson decays, Nucl. Phys. B 434 (1995) 606 [hep-ph/9409309] [INSPIRE].
H.-Y. Cheng, Weak annihilation and the effective parameters a 1 and a 2 in nonleptonic D decays, Eur. Phys. J. C 26 (2003) 551 [hep-ph/0202254] [INSPIRE].
BaBar collaboration, B. Aubert et al., Measurement of the branching fractions of the radiative charm decays \( {D}^0\to {\overline{K}}^{\ast 0}\gamma \) and D 0 → \( \phi \) γ, Phys. Rev. D 78 (2008) 071101 [arXiv:0808.1838] [INSPIRE].
J. Lyon and R. Zwicky, Anomalously large \( {\mathcal{O}}_8 \) and long-distance chirality from A CP[D 0 → (ρ 0 , ω)γ](t), arXiv:1210.6546 [INSPIRE].
G.F. Giudice, G. Isidori and P. Paradisi, Direct CP-violation in charm and flavor mixing beyond the SM, JHEP 04 (2012) 060 [arXiv:1201.6204] [INSPIRE].
Y. Amhis et al., Averages of b-hadron, c-hadron and τ -lepton properties as of summer 2016, arXiv:1612.07233 [INSPIRE].
W. Buchmüller, R. Ruckl and D. Wyler, Leptoquarks in lepton-quark collisions, Phys. Lett. B 191 (1987) 442 [Erratum ibid. B 448 (1999) 320] [INSPIRE].
S. Davidson, D.C. Bailey and B.A. Campbell, Model independent constraints on leptoquarks from rare processes, Z. Phys. C 61 (1994) 613 [hep-ph/9309310] [INSPIRE].
I. Doršner, S. Fajfer, A. Greljo, J.F. Kamenik and N. Košnik, Physics of leptoquarks in precision experiments and at particle colliders, Phys. Rept. 641 (2016) 1 [arXiv:1603.04993] [INSPIRE].
G. Hiller, D. Loose and K. Schönwald, Leptoquark flavor patterns & B decay anomalies, JHEP 12 (2016) 027 [arXiv:1609.08895] [INSPIRE].
M. Carpentier and S. Davidson, Constraints on two-lepton, two quark operators, Eur. Phys. J. C 70 (2010) 1071 [arXiv:1008.0280] [INSPIRE].
C. Greub, T. Hurth and D. Wyler, Virtual O(α s ) corrections to the inclusive decay b → sγ, Phys. Rev. D 54 (1996) 3350 [hep-ph/9603404] [INSPIRE].
L. Lavoura, General formulae for f 1 → f 2 γ, Eur. Phys. J. C 29 (2003) 191 [hep-ph/0302221] [INSPIRE].
F. Gabbiani, E. Gabrielli, A. Masiero and L. Silvestrini, A complete analysis of FCNC and CP constraints in general SUSY extensions of the Standard Model, Nucl. Phys. B 477 (1996) 321 [hep-ph/9604387] [INSPIRE].
S. Prelovsek and D. Wyler, c → uγ in the minimal supersymmetric Standard Model, Phys. Lett. B 500 (2001) 304 [hep-ph/0012116] [INSPIRE].
N. Carrasco et al., \( {D}^0-{\overline{D}}^0 \) mixing in the Standard Model and beyond from N f = 2 twisted mass QCD, Phys. Rev. D 90 (2014) 014502 [arXiv:1403.7302] [INSPIRE].
M. Frank and S.-Q. Nie, Chargino contributions to ϵ ′ /ϵ in the left right supersymmetric model, J. Phys. G 30 (2004) 181 [hep-ph/0306020] [INSPIRE].
G. Hiller and A. Kagan, Probing for new physics in polarized Λ b decays at the Z, Phys. Rev. D 65 (2002) 074038 [hep-ph/0108074] [INSPIRE].
A.F. Falk and M.E. Peskin, Production, decay and polarization of excited heavy hadrons, Phys. Rev. D 49 (1994) 3320 [hep-ph/9308241] [INSPIRE].
P. Singer and D.-X. Zhang, Two-body Cabibbo suppressed decays of charmed baryons into vector mesons and into photons, Phys. Rev. D 54 (1996) 1225 [hep-ph/9603426] [INSPIRE].
P. Böer, T. Feldmann and D. van Dyk, Angular analysis of the decay Λ b → Λ(→ N π)ℓ + ℓ −, JHEP 01 (2015) 155 [arXiv:1410.2115] [INSPIRE].
A. Khodjamirian, C. Klein, T. Mannel and Y.-M. Wang, Form factors and strong couplings of heavy baryons from QCD light-cone sum rules, JHEP 09 (2011) 106 [arXiv:1108.2971] [INSPIRE].
C.-F. Li, Y.-L. Liu, K. Liu, C.-Y. Cui and M.-Q. Huang, Analysis of the semileptonic decay Λ c → ne + ν e , J. Phys. G 44 (2017) 075006 [arXiv:1610.05418] [INSPIRE].
T. Gutsche, M.A. Ivanov, J.G. Körner, V.E. Lyubovitskij and P. Santorelli, Heavy-to-light semileptonic decays of Λ b and Λ c baryons in the covariant confined quark model, Phys. Rev. D 90 (2014) 114033 [Erratum ibid. D 94 (2016) 059902] [arXiv:1410.6043] [INSPIRE].
R.N. Faustov and V.O. Galkin, Semileptonic decays of Λ c baryons in the relativistic quark model, Eur. Phys. J. C 76 (2016) 628 [arXiv:1610.00957] [INSPIRE].
T. Uppal and R.C. Verma, Weak electromagnetic decays of charm baryons, Phys. Rev. D 47 (1993) 2858 [INSPIRE].
M. Lisovyi, A. Verbytskyi and O. Zenaiev, Combined analysis of charm-quark fragmentation-fraction measurements, Eur. Phys. J. C 76 (2016) 397 [arXiv:1509.01061] [INSPIRE].
M. Galanti, A. Giammanco, Y. Grossman, Y. Kats, E. Stamou and J. Zupan, Heavy baryons as polarimeters at colliders, JHEP 11 (2015) 067 [arXiv:1505.02771] [INSPIRE].
Y. Kats, Measuring c-quark polarization in W + c samples at ATLAS and CMS, JHEP 11 (2016) 011 [arXiv:1512.00438] [INSPIRE].
E791 collaboration, E.M. Aitala et al., Mass splitting and production of Σ 0 c and \( {\varSigma}_{{}^c}^{{{}^{+}}^{+}} \) measured in 500 GeV π − n interactions, Phys. Lett. B 379 (1996) 292 [hep-ex/9604007] [INSPIRE].
CLEO collaboration, G. Brandenburg et al., Observation of two excited charmed baryons decaying into \( {\varLambda}_{{}^c}^{+}{\pi}^{\pm } \), Phys. Rev. Lett. 78 (1997) 2304 [INSPIRE].
J.G. Korner, A. Pilaftsis and M.M. Tung, One loop QCD mass effects in the production of polarized bottom and top quarks, Z. Phys. C 63 (1994) 575 [hep-ph/9311332] [INSPIRE].
K.G. Chetyrkin, J.H. Kuhn and M. Steinhauser, RunDec: a Mathematica package for running and decoupling of the strong coupling and quark masses, Comput. Phys. Commun. 133 (2000) 43 [hep-ph/0004189] [INSPIRE].
UTfit collaboration webpage, http://www.utfit.org/UTfit/.
S. Aoki et al., Review of lattice results concerning low-energy particle physics, Eur. Phys. J. C 77 (2017) 112 [arXiv:1607.00299] [INSPIRE].
A. Bharucha, D.M. Straub and R. Zwicky, B → V ℓ + ℓ − in the Standard Model from light-cone sum rules, JHEP 08 (2016) 098 [arXiv:1503.05534] [INSPIRE].
CLEO collaboration, S. Dobbs et al., First measurement of the form factors in the decays D 0 → ρ − e + ν e and D + → ρ 0 e + ν e , Phys. Rev. Lett. 110 (2013) 131802 [arXiv:1112.2884] [INSPIRE].
J.M. Flynn and C.T. Sachrajda, Heavy quark physics from lattice QCD, Adv. Ser. Direct. High Energy Phys. 15 (1998) 402 [hep-lat/9710057] [INSPIRE].
UKQCD collaboration, J. Gill, Semileptonic decay of a heavy light pseudoscalar to a light vector meson, Nucl. Phys. Proc. Suppl. 106 (2002) 391 [hep-lat/0109035] [INSPIRE].
BESIII collaboration, M. Ablikim et al., Measurement of the form factors in the decay D + → ωe + ν e and search for the decay D + → \( \phi \) e + ν e , Phys. Rev. D 92 (2015) 071101 [arXiv:1508.00151] [INSPIRE].
Y.-L. Wu, M. Zhong and Y.-B. Zuo, B (s) , D (s) → pi, K, η, ρ, K ∗ , ω, \( \phi \) transition form factors and decay rates with extraction of the CKM parameters |V ub |, |V cs |, |V cd |, Int. J. Mod. Phys. A 21 (2006) 6125 [hep-ph/0604007] [INSPIRE].
D. Melikhov and B. Stech, Weak form-factors for heavy meson decays: an update, Phys. Rev. D 62 (2000) 014006 [hep-ph/0001113] [INSPIRE].
R.C. Verma, Decay constants and form factors of s-wave and p-wave mesons in the covariant light-front quark model, J. Phys. G 39 (2012) 025005 [arXiv:1103.2973] [INSPIRE].
S. Fajfer and J.F. Kamenik, Charm meson resonances and D → V semileptonic form-factors, Phys. Rev. D 72 (2005) 034029 [hep-ph/0506051] [INSPIRE].
J. Charles, A. Le Yaouanc, L. Oliver, O. Pene and J.C. Raynal, Heavy to light form-factors in the heavy mass to large energy limit of QCD, Phys. Rev. D 60 (1999) 014001 [hep-ph/9812358] [INSPIRE].
R. Casalbuoni, A. Deandrea, N. Di Bartolomeo, R. Gatto, F. Feruglio and G. Nardulli, Effective Lagrangian for heavy and light mesons: semileptonic decays, Phys. Lett. B 299 (1993) 139 [hep-ph/9211248] [INSPIRE].
P.L. Cho and M.B. Wise, Comment on D * s → D s π 0 decay, Phys. Rev. D 49 (1994) 6228 [hep-ph/9401301] [INSPIRE].
A.J. Buras, A. Czarnecki, M. Misiak and J. Urban, Completing the NLO QCD calculation of \( \overline{B}\to {X}_s\gamma \), Nucl. Phys. B 631 (2002) 219 [hep-ph/0203135] [INSPIRE].
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de Boer, S., Hiller, G. Rare radiative charm decays within the standard model and beyond. J. High Energ. Phys. 2017, 91 (2017). https://doi.org/10.1007/JHEP08(2017)091
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DOI: https://doi.org/10.1007/JHEP08(2017)091