====== TTP97-04 HQET chromomagnetic interaction at two loops  ======
 
 
   <hidden TTP97-04  HQET chromomagnetic interaction at two loops  > We present the coefficient of the chromomagnetic interaction operator,
 the only unknown coefficient in the Heavy Quark Effective Theory
 (HQET) lagrangian up to the $1/m$ level,
 with the two--loop accuracy by matching scattering amplitudes
 of an on--shell heavy quark in an external field in full QCD and HQET,
 and obtain the two--loop anomalous dimension of this operator in HQET.
 
 </hidden>
|**Andrzej Czarnecki and Andrey Grozin**  | 
|** Phys. Lett. B405 142 1997  **  |
| {{preprints:1997:ttp97-04.pdf|PDF}} {{preprints:1997:ttp97-04.ps|PostScript}} [[http://arxiv.org/abs/hep-ph/9701415|arXiv]]   |
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