Abstract
We present the first full-fledged study of the flavor-exotic isoscalar Tbb−≡bbu¯d¯ tetraquark with spin and parity JP=1+. We report accurate solutions of the four-body problem in a quark model, characterizing the structure of the state as a function of the ratio MQ/mq of the heavy to light quark masses. For such a standard constituent model, Tbb− lies approximately 150 MeV below the strong decay threshold B−B⁎¯0 and 105 MeV below the electromagnetic decay threshold B−B¯0γ. We evaluate the lifetime of Tbb−, identifying the promising decay modes where the tetraquark might be looked for in future experiments. Its total decay width is Γ≈87×10−15 GeV and therefore its lifetime τ≈ 7.6 ps. The promising final states are B⁎−D⁎+ℓ−ν¯ℓ and B⁎¯0D⁎0ℓ−ν¯ℓ among the semileptonic decays, and B⁎−D⁎+Ds⁎−, B⁎¯0D⁎0Ds⁎−, and B⁎−D⁎+ρ− among the nonleptonic ones. The semileptonic decay to the isoscalar JP=0+ tetraquark Tbc0 is also relevant but it is not found to be dominant. There is a broad consensus about the existence of this tetraquark, and its detection will validate our understanding of the low-energy realizations of Quantum Chromodynamics (QCD) in the multiquark sector.
Highlights
Hadronic physics has been much stimulated during the last two decades by the experimental discovery of several new resonances in the hidden-charm sector, resonances that are hardly accommodated in the traditional quark-antiquark or three-quark picture [1]
The promising final states are B∗− D∗+ l− νl and B∗0 D∗0 l− νl among the semileptonic decays, and B∗− D∗+ Ds∗−, B∗0 D∗0 Ds∗−, and B∗− D∗+ ρ− among the nonleptonic ones
There is a broad consensus about the existence of this tetraquark, and its detection will validate our understanding of the low-energy realizations of Quantum Chromodynamics (QCD) in the multiquark sector
Summary
Hadronic physics has been much stimulated during the last two decades by the experimental discovery of several new resonances in the hidden-charm sector, resonances that are hardly accommodated in the traditional quark-antiquark or three-quark picture [1]. [7], tetbhhneeeelormwgccyatsdohsifeqoaufsattQhrrokeQndignoduidqtbehulceyaa-rycΞkh.+ctach+rArmesbsshbauroamylrdoyinnoBgn, ̄BtΞthh∗+ceac.+tm,ItndahisesRscboeobvff.edtr[i8heqd]eu, ab(try0hk)et1hb+heienLaddvHoinyuCg-bqblueyCna-berorkolgl-tasytbyomoimnrmaatteeiottTrrnby−ab[q1mut5eaa]t,rsrkisasqriuusesaleaerdstktitoiimonsscatathlelieindbksritaanomtgebethehaeeas2vb1ty5ihn-MalditgienhoVgtf and doubly-heavy-light mesons and baryons are combined with leading-order corrections for finite heavy-quark mass, corresponding to hyperfine spin-dependent terms and kinetic energy shift that depends only on the light degrees of freedom This leads to predict that the Tb−b state is stable against strong decays. [9], the Schrodinger equation is solved with a potential extracted from a lattice QCD calculation for static heavy quarks, in a regime where the pion mass is mπ ∼ 340 MeV, and again, evidence is found for a stable isoscalar doubly-bottom axial-vector tetraquark. The compelling theoretical evidence for the existence of a Tb−b tetraquark has led to preliminary studies of its lifetime and weak decay modes
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
