### Abstract

It has been suggested in Ref. that the disagreement between theoretical calculations and experimental observations for the rate for the process e+e-→J/ψ+ηc at the B factories might be resolved by using the light-cone method to take into account the relative momentum of the heavy-quark and antiquark in the quarkonia. The light-cone result for the production cross section in Ref. is almost an order-of-magnitude larger than existing NRQCD factorization results. We investigate this apparent theoretical discrepancy. We compute light-cone distribution functions by making use of quarkonium wave functions from the Cornell potential model. Our light-cone distribution functions are similar in shape to those of Ref. and yield a similar cross section. However, when we subtract parts of the light-cone distribution functions that correspond to corrections of relative-order αs in the NRQCD approach, we find that the cross section decreases by about a factor of three. When we set certain renormalization factors Zi in the light-cone calculation equal to unity, we find a further reduction in the cross section of about a factor of two. The resulting light-cone cross section is similar in magnitude to the NRQCD factorization cross sections and shows only a modest enhancement over the light-cone cross section in which the relative momentum of the heavy-quark and antiquark is neglected.

Original language | English |
---|---|

Article number | 114028 |

Journal | Physical Review D - Particles, Fields, Gravitation and Cosmology |

Volume | 74 |

Issue number | 11 |

DOIs | |

Publication status | Published - 2006 Dec 1 |

### Fingerprint

### ASJC Scopus subject areas

- Physics and Astronomy(all)
- Nuclear and High Energy Physics
- Mathematical Physics

### Cite this

*Physical Review D - Particles, Fields, Gravitation and Cosmology*,

*74*(11), [114028]. https://doi.org/10.1103/PhysRevD.74.114028

**Reconciling the light-cone and nonrelativistic QCD approaches to calculating e+e-→J/ψ+ηc.** / Bodwin, Geoffrey T.; Kang, Daekyoung; Lee, Jungil.

Research output: Contribution to journal › Article

*Physical Review D - Particles, Fields, Gravitation and Cosmology*, vol. 74, no. 11, 114028. https://doi.org/10.1103/PhysRevD.74.114028

}

TY - JOUR

T1 - Reconciling the light-cone and nonrelativistic QCD approaches to calculating e+e-→J/ψ+ηc

AU - Bodwin, Geoffrey T.

AU - Kang, Daekyoung

AU - Lee, Jungil

PY - 2006/12/1

Y1 - 2006/12/1

N2 - It has been suggested in Ref. that the disagreement between theoretical calculations and experimental observations for the rate for the process e+e-→J/ψ+ηc at the B factories might be resolved by using the light-cone method to take into account the relative momentum of the heavy-quark and antiquark in the quarkonia. The light-cone result for the production cross section in Ref. is almost an order-of-magnitude larger than existing NRQCD factorization results. We investigate this apparent theoretical discrepancy. We compute light-cone distribution functions by making use of quarkonium wave functions from the Cornell potential model. Our light-cone distribution functions are similar in shape to those of Ref. and yield a similar cross section. However, when we subtract parts of the light-cone distribution functions that correspond to corrections of relative-order αs in the NRQCD approach, we find that the cross section decreases by about a factor of three. When we set certain renormalization factors Zi in the light-cone calculation equal to unity, we find a further reduction in the cross section of about a factor of two. The resulting light-cone cross section is similar in magnitude to the NRQCD factorization cross sections and shows only a modest enhancement over the light-cone cross section in which the relative momentum of the heavy-quark and antiquark is neglected.

AB - It has been suggested in Ref. that the disagreement between theoretical calculations and experimental observations for the rate for the process e+e-→J/ψ+ηc at the B factories might be resolved by using the light-cone method to take into account the relative momentum of the heavy-quark and antiquark in the quarkonia. The light-cone result for the production cross section in Ref. is almost an order-of-magnitude larger than existing NRQCD factorization results. We investigate this apparent theoretical discrepancy. We compute light-cone distribution functions by making use of quarkonium wave functions from the Cornell potential model. Our light-cone distribution functions are similar in shape to those of Ref. and yield a similar cross section. However, when we subtract parts of the light-cone distribution functions that correspond to corrections of relative-order αs in the NRQCD approach, we find that the cross section decreases by about a factor of three. When we set certain renormalization factors Zi in the light-cone calculation equal to unity, we find a further reduction in the cross section of about a factor of two. The resulting light-cone cross section is similar in magnitude to the NRQCD factorization cross sections and shows only a modest enhancement over the light-cone cross section in which the relative momentum of the heavy-quark and antiquark is neglected.

UR - http://www.scopus.com/inward/record.url?scp=33846344285&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33846344285&partnerID=8YFLogxK

U2 - 10.1103/PhysRevD.74.114028

DO - 10.1103/PhysRevD.74.114028

M3 - Article

AN - SCOPUS:33846344285

VL - 74

JO - Physical review D: Particles and fields

JF - Physical review D: Particles and fields

SN - 0556-2821

IS - 11

M1 - 114028

ER -