### Abstract

Recent observations of the spectrum of [Formula Presented] produced in [Formula Presented] collisions at the [Formula Presented] resonance are in conflict with fixed-order calculations using the nonrelativistic QCD effective field theory. One problem is that leading order color-octet mechanisms predict an enhancement of the cross section for [Formula Presented] with a maximal energy that is not observed in the data. However, in this region of phase space large perturbative corrections (Sudakov logarithms) as well as enhanced nonperturbative effects are important. In this paper we use the newly developed soft-collinear effective theory (SCET) to systematically include these effects. We find that these corrections significantly broaden the color-octet contribution to the [Formula Presented] spectrum. Our calculation employs a one-stage renormalization group evolution rather than the two-stage evolution used in previous SCET calculations. We give a simple argument for why the two methods yield identical results to lowest order in the SCET power counting.

Original language | English (US) |
---|---|

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

Volume | 68 |

Issue number | 9 |

DOIs | |

State | Published - Jan 1 2003 |

Externally published | Yes |

### Fingerprint

### ASJC Scopus subject areas

- Nuclear and High Energy Physics
- Physics and Astronomy (miscellaneous)

### Cite this

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

*68*(9). https://doi.org/10.1103/PhysRevD.68.094011

**Resumming the color-octet contribution to [Formula Presented].** / Fleming, Sean P; Leibovich, Adam K.; Mehen, Thomas.

Research output: Contribution to journal › Article

*Physical Review D - Particles, Fields, Gravitation and Cosmology*, vol. 68, no. 9. https://doi.org/10.1103/PhysRevD.68.094011

}

TY - JOUR

T1 - Resumming the color-octet contribution to [Formula Presented]

AU - Fleming, Sean P

AU - Leibovich, Adam K.

AU - Mehen, Thomas

PY - 2003/1/1

Y1 - 2003/1/1

N2 - Recent observations of the spectrum of [Formula Presented] produced in [Formula Presented] collisions at the [Formula Presented] resonance are in conflict with fixed-order calculations using the nonrelativistic QCD effective field theory. One problem is that leading order color-octet mechanisms predict an enhancement of the cross section for [Formula Presented] with a maximal energy that is not observed in the data. However, in this region of phase space large perturbative corrections (Sudakov logarithms) as well as enhanced nonperturbative effects are important. In this paper we use the newly developed soft-collinear effective theory (SCET) to systematically include these effects. We find that these corrections significantly broaden the color-octet contribution to the [Formula Presented] spectrum. Our calculation employs a one-stage renormalization group evolution rather than the two-stage evolution used in previous SCET calculations. We give a simple argument for why the two methods yield identical results to lowest order in the SCET power counting.

AB - Recent observations of the spectrum of [Formula Presented] produced in [Formula Presented] collisions at the [Formula Presented] resonance are in conflict with fixed-order calculations using the nonrelativistic QCD effective field theory. One problem is that leading order color-octet mechanisms predict an enhancement of the cross section for [Formula Presented] with a maximal energy that is not observed in the data. However, in this region of phase space large perturbative corrections (Sudakov logarithms) as well as enhanced nonperturbative effects are important. In this paper we use the newly developed soft-collinear effective theory (SCET) to systematically include these effects. We find that these corrections significantly broaden the color-octet contribution to the [Formula Presented] spectrum. Our calculation employs a one-stage renormalization group evolution rather than the two-stage evolution used in previous SCET calculations. We give a simple argument for why the two methods yield identical results to lowest order in the SCET power counting.

UR - http://www.scopus.com/inward/record.url?scp=85039021818&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85039021818&partnerID=8YFLogxK

U2 - 10.1103/PhysRevD.68.094011

DO - 10.1103/PhysRevD.68.094011

M3 - Article

AN - SCOPUS:85039021818

VL - 68

JO - Physical review D: Particles and fields

JF - Physical review D: Particles and fields

SN - 0556-2821

IS - 9

ER -