Rare<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msup><mml:mi>B</mml:mi><mml:mo>−</mml:mo></mml:msup><mml:mo>→</mml:mo><mml:mi>Λ</mml:mi><mml:mover accent="true"><mml:mi>p</mml:mi><mml:mo>¯</mml:mo></mml:mover><mml:mi>ν</mml:mi><mml:mover accent="true"><mml:mi>ν</mml:mi><mml:mo>¯</mml:mo></mml:mover></mml:math>decay

Geng, C. Q.; Hsiao, Y. K.

doi:10.1103/physrevd.85.094019

“…By setting n = 3 to count the number of the hard gluons for the B → pp transition [28], the form of 1/t n that peaks at t → (m p + mp) 2 and decreases with increasing t corresponds with the threshold enhancement. It is interesting to note that we have succeeded in explaining the experimental data observed in baryonic B decays, in particular the branching ratios [24,25,29,30]…”

mentioning

confidence: 71%

Identifying glueball at 3.02 GeV in baryonic B decays

Hsiao

¹

,

Geng

²

2013

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We examine the nature of the unknown enhancement around 3 GeV observed by the BABAR collaboration in the m pp spectrum of theB 0 → ppD 0 decay. Suspecting that the peak is a resonance, which can be neither identified as a charmonium state, such as η c or J/ψ, nor classified as one of the light-flavor mesons, we conclude that it corresponds to a glueball fitted as X (3020) with (m X , Γ X ) = (3020 ± 8, 107 ± 30) MeV, which could be the first glueball state above 3 GeV.This state also appears in the m pp spectrum of theB 0 → ppD * 0 decay.Introduction-The glueball (G) is a bound state that contains no valence quark but gluons only. This is because gluons, which are charged with colors in QCD and force carriers to bind quarks becoming mesons and baryons, can also glue themselves together to form a bound state. Since it is a unique feature purely for the non-Abelian gauge fields, whether the existence of the gluon condensates can be well established or not appears to be a real test for QCD.In principle, the searches for glueballs depend on gluon-rich processes, such as the radiative J/Ψ decays via cc → γgg. However, the glueball identifications are inconclusive [1-3], which may be illustrated by the following discussions on the scalar, tensor, and pseudoscalar glueballs. With the predicted mass around 1.7 GeV [4,5], the lightest scalar glueball with the quantum number of J P C = 0 ++ is allowed to mix with nearby qq mesons in the spectrum.Since there are two states, f 0 (1500) and f 0 (1710), proposed to be composed of the glueball in different mixing scenarios [6], the identification is obscure. The lightest tensor glueball with J P C = 2 ++ is believed to have a mass close to 1.3 GeV in the MIT bag model [7] and 2.4 GeV in the lattice QCD calculation [4,5]. For the former, both f 2 (1270) and f ′ 2 (1525) as the ground states of the 2 ++ mesons are argued to have the 2 ++ glueball content [8], while for the later [2], f J (2220) (J = 2 or 4) [9, 10] and f 2 (2340) [11] are considered to be the candidates, in which the existence of f J (2220) is still questionable [12]. Unlike 0 ++ and 2 ++ , the difficulty to establish the lightest 0 −+ pseudoscalar glueball is that the predicted mass around 2.6 GeV in the lattice QCD calculation [4,5] has no correspondence with the data.Nonetheless, η(1405) seems to be a perfect candidate [13]. Particularly, the unseen in γγ reactions [14] reflects that its components are gluons. In addition, X(1835), measured first in the J/Ψ → γpp decays [15], is another possible glueball state [16] at a mass below 2 GeV.

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“…We are able to relate different B b → B n transition form factors based on SU(3) flavor and SU(2) spin symmetries, which have been used to connect the space-like B n → B ′ n transition form factors in the neutron decays [27], and the time-like 0 → B nB ′ n baryonic as well as B → B nB ′ n transition form factors in the baryonic B decays [28][29][30][31][32]. As a result, we obtain (f 1 (0), g 1 (0)) = (C, C), (− 2/3C, − 2/3C), and (0, 0) with C a constant for p|ūγ µ (γ 5 )b|Λ b , Λ|sγ µ (γ 5 )b|Λ b , and Σ 0 |sγ µ (γ 5 )b|Λ b , which are the same as those in Ref.…”

Section: Introductionmentioning

confidence: 99%

Fragmentation fractions of two-body b -baryon decays

Hsiao

¹

,

Lin

²

,

Luo

³

et al. 2015

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“…is the momentum of one of the Kπ pairs in the B (s) meson rest frame. The four-body phase space has been derived in the analyses of the K → ππlν decay [108], the semileptonicB → D(D * )πlν decays [109], semileptonic baryonic decays [110,111], and four-body baryonic decays [112]. One can confirm that eq.…”

Section: Helicity Amplitudesmentioning

confidence: 63%

“…(3.1) is equivalent to those in refs. [110,112] by appropriate variable changes. Replacing the helicity angles θ i by the meson momentum fractions ζ i via eq.…”

Section: Helicity Amplitudesmentioning

confidence: 99%

Four-body decays B(s) → (Kπ)S/P(Kπ)S/P in the perturbative QCD approach

Rui

¹

,

Li

²

,

Li

³

2021

J. High Energ. Phys.

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We investigate the four-body decays B(s) → (Kπ)S/P(Kπ)S/P in the Kπ-pair invariant mass region around the K*(892) resonance in the perturbative QCD (PQCD) approach, where (Kπ)S/P denotes a S- or P-wave Kπ configuration. The contributions from the P-wave resonance K*(892) and from possible S-wave components are included into the parametrization of the Kπ two-meson distribution amplitudes, which are the non-perturbative inputs in this formalism. We calculate the branching ratio for each resonance and observe sizable S-wave contributions to the Bs modes, well consistent with recently available LHCb data. We also deduce the polarization fractions for the $$ {K}^{\ast }{\overline{K}}^{\ast } $$ K ∗ K ¯ ∗ final states, and compare our predictions to those in previous PQCD analyses of the corresponding two-body B → $$ {K}^{\ast }{\overline{K}}^{\ast } $$ K ∗ K ¯ ∗ decays. The polarization puzzle associated with the two U-spin related channels B0 → $$ {K}^{\ast 0}{\overline{K}}^{\ast 0} $$ K ∗ 0 K ¯ ∗ 0 and $$ {B}_s^0\to {K}^{\ast 0}{\overline{K}}^{\ast 0} $$ B s 0 → K ∗ 0 K ¯ ∗ 0 still exists. In addition to direct CP asymmetries, triple-product asymmetries and S-wave induced direct CP asymmetries originating from the interference among various helicity amplitudes, are presented. It is shown that true triple-product asymmetries are rather small, while direct CP asymmetries and S-wave-induced direct CP asymmetries are significant in some decays. Our results will be subject to stringent tests with precise data from B factories in the near future.

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RareB−→Λp¯νν¯decay

Cited by 24 publications

References 48 publications

Identifying glueball at 3.02 GeV in baryonic B decays

Identifying glueball at 3.02 GeV in baryonic B decays

Fragmentation fractions of two-body b -baryon decays

Four-body decays B(s) → (Kπ)S/P(Kπ)S/P in the perturbative QCD approach

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