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Definition and Extraction of Bottom and Charm Quark Masses. TexPoint fonts used in EMF. Read the TexPoint manual before you delete this box.: A A A A A A A A A. Outline. Remarks on Quark Masses bottom charm Incl. B decay moments vs. Sum Rules. Remarks on Quark Masses. possible.
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Definition and Extraction of Bottom and Charm Quark Masses Joint WS on Vxb at B-factories, Heidelberg , Dec 14-16 2007 TexPoint fonts used in EMF. Read the TexPoint manual before you delete this box.: AAAAAAAAA
Outline • Remarks on Quark Masses • bottom • charm • Incl. B decay moments vs. Sum Rules Joint WS on Vxb at B-factories, Heidelberg , Dec 14-16 2007
Remarks on Quark Masses possible We only want to use short-distance mass scheme that do not suffer from the renormalon inherent to the pole scheme! Joint WS on Vxb at B-factories, Heidelberg , Dec 14-16 2007
Classes of Short Distance Masses Different classes are “optimal” schemes for different types of processes. MS schemes: • subtraction of UV-div’s in dim reg ( ), running • for processes where quark is energetic or off-shell Jet schemes: • moments of jet functions describing collinear gluon radiation • for jet observables (e.g. thrust in the dijet limit) Threshold schemes: • for processes where quarks are close to mass-shell Also note: The issue of defining a short-distance mass is independent of defining renormalon-free matrix elements for power corrections ! (“1S” scheme, “kinetic” scheme, “shape fct” scheme) Joint WS on Vxb at B-factories, Heidelberg , Dec 14-16 2007
Threshold Masses Threshold schemes: • for processes where quarks are close to mass-shell Kinetic mass: • from B meson form factor sum rules • cut-off dependent Bigi, Uraltsev 1S mass: • from mass • scale independent Ligeti, Manohar, AHH Shape fct mass: • from moments of B-decay shape function • cut-off + renormalization scale dependent Neubert Joint WS on Vxb at B-factories, Heidelberg , Dec 14-16 2007
Threshold Masses Threshold schemes: • for processes where quarks are close to mass-shell PS mass: • from oth moment of static potential in mom space • cut-off dependent Beneke Renormalon subtracted masses: Pineda There is no “optimal” threshold mass. All can do a good job when used and defined correctly. Relating masses from different classes can introduce correlations to other parameters. (3-loop) hep-ph/0008102 1S mass Joint WS on Vxb at B-factories, Heidelberg , Dec 14-16 2007
… mass issue has big impact Heavy Quark Effective Theory: Joint WS on Vxb at B-factories, Heidelberg , Dec 14-16 2007
Quark Mass Tables CKM-WS Yellow Report hep-ph/030432 • numerical program • include shape fct mass Joint WS on Vxb at B-factories, Heidelberg , Dec 14-16 2007
Bottom Quark Mass • Spectral Moments of Inclusive B Decays • Sum Rules • relativistic • non-relativistic Joint WS on Vxb at B-factories, Heidelberg , Dec 14-16 2007
Global Fits Experimental Data: Joint WS on Vxb at B-factories, Heidelberg , Dec 14-16 2007
Global Fits Theoretical Moments: technology for full exists: (Anastasiou, Melnikov, Petriello) • theory input: perturbative QCD power corrections are done ! (Becher, Boos, Lunghi) • Gambino, Uraltsev (2004) • Bauer, Ligeti, Manohar, Trott (2004) • expansion • expansion • input: meson mass difference • expansion scheme: • mass scheme: threshold mass ( (A) kinetic, (B) 1S ) • short-distance mass (MSbar) • eliminated Joint WS on Vxb at B-factories, Heidelberg , Dec 14-16 2007
Global Fits Fit Results: (2007) ? • expansion scheme? • mass scheme ? • uncertainties underestimated ? Number for kinetic mass without seem to be incompatible with sum rules. Joint WS on Vxb at B-factories, Heidelberg , Dec 14-16 2007
Global Fits Fit Results: (2007) ? (2007, only BELLE) Joint WS on Vxb at B-factories, Heidelberg , Dec 14-16 2007
Sum Rules nonperturbative power corrections very small Joint WS on Vxb at B-factories, Heidelberg , Dec 14-16 2007
Sum Rules Relativistic: Kühn, Steinhauser, Sturm (2006) 3-loop for n=1 (update) Boughezal, Czakon, Schutzmeier (2006) 3-loop for n=1 (update) Joint WS on Vxb at B-factories, Heidelberg , Dec 14-16 2007
Sum Rules Non-Relativistic: NNLL RG-improved analyis (w.i.p.) partial result: Pineda, Signer Joint WS on Vxb at B-factories, Heidelberg , Dec 14-16 2007
Charm Quark Mass • Spectral Moments of Inclusive B Decays • Sum Rules • relativistic Joint WS on Vxb at B-factories, Heidelberg , Dec 14-16 2007
Charm mass from B decays Buchmüller etal. Joint WS on Vxb at B-factories, Heidelberg , Dec 14-16 2007
Charm Mass from Sum Rules AH,Jamin, 2004 usual fixed order: fixed RGI-A : RGI-B : pert. Behavior of moments: (2-loops) Joint WS on Vxb at B-factories, Heidelberg , Dec 14-16 2007
Charm Mass from Sum Rules Contour analysis should be done (w.i.p.) AH,Jamin, 2004 (2-loops, accounting for countour analysis) Kühn, Steinhauser, (Sturm) (2001/2006) (3-loops fixed o.) (2-loops fixed o.) Boughezal, Czakon, Schutzmeier (2006) (3-loops fixed o.) Joint WS on Vxb at B-factories, Heidelberg , Dec 14-16 2007