Citation: W.-M.Yaoetal. (ParticleDataGroup),J.Phys.G33,1(2006)(URL:http://pdg.lbl.gov) γ PC −− I(J ) = 0,1(1 ) γγγγ MMMMAAAASSSSSSSS For a review of the photon mass, see BYRNE 77. VALUE (eV) CL% DOCUMENT ID TECN COMMENT <<<< 6666 ××××11110000−−−−11117777 1RYUTOV 97 MHD of solar wind • • • We do not use the following data for averages, fits, limits, etc. • • • < 1.4 ×10−7 ACCIOLY 04 Dispersion of GHz radio waves by sun < 7 ×10−19 2LUO 03 Modulation torsion balance < 1 ×10−17 3LAKES 98 Torque on toroid bal- ance < 9 ×10−16 90 4FISCHBACH 94 Earth magnetic field <(4.73±0.45)×10−12 5CHERNIKOV 92 SQID Ampere-law null test <(9.0 ±8.1 )×10−10 6RYAN 85 Coulomb-law null test < 3 ×10−27 7CHIBISOV 76 Galactic magnetic field < 6 ×10−16 99.7 DAVIS 75 Jupiter magnetic field < 7.3 ×10−16 HOLLWEG 74 Alfven waves < 6 ×10−17 8FRANKEN 71 Low freq. res. cir. < 1 ×10−14 WILLIAMS 71 CNTR Tests Gauss law < 2.3 ×10−15 GOLDHABER 68 Satellite data < 6 ×10−15 8PATEL 65 Satellite data < 6 ×10−15 GINTSBURG 64 Satellite data 1 RYUTOV 97 uses a magnetohydrodynamics argument concerning survival of the Sun’s field to the radius of the Earth’s orbit. “To reconcile observations to theory, one has to reduce [the photon mass] by approximately an order of magnitude compared with” DAVIS 75. 2LUO 03 determine a limit on µ2 AAAA < 1.1×10−11 T m/m2 (with µ−1=characteristic length for photon mass; AAAA=ambient vector potential) — similar to the LAKES 98 tech- nique. UnlikeLAKES98whousedstatic,theauthorsuseddynamictorsion balance. As- sumingAAAAtobe1012Tm,theyobtainµ<1.2×10−51g,equivalentto6.7×10−19eV. The rotating modified Cavendish balance removes dependence on the direction of AAAA. GOLDHABER 03 argue that because plasma current effects are neglected, the LUO 03 limit does not provide the best available limit on µ2AAAA nor a reliable limit at all on µ. Thereason is thattheAAAA associated withclustermagnetic fieldscould become arbitrarily small in plasma voids, whose existence would be compatible with present knowledge. LUO 03B reply that fields of distant clusters are not accurately mapped, but assert that a zero AAAA is unlikely given what we know about the magnetic field in our galaxy. 3 LAKES 98 reports limits on torque on a toroid Cavendish balance, obtaining a limit on µ2AAAA < 2×10−9Tm/m2 via the Maxwell-Proca equations, where µ−1 is the charac- teristic length associated with the photon mass and AAAA is the ambient vector potential in the Lorentz gauge. Assuming AAAA ≈ 1 × 1012Tm due to cluster fields he obtains µ−1 > 2×1010m, corresponding to µ < 1×10−17 eV. A more conservative limit, using AAAA ≈ (1 µG)×(600 pc) based on the galactic field, is µ−1 > 1 × 109m or µ < 2×10−16 eV. 4FISCHBACH 94 report < 8×10−16 with unknown CL. We report Bayesian CL used elsewhere in these Listings and described in the Statistics section. HTTP://PDG.LBL.GOV Page 1 Created: 7/6/2006 16:35 Citation: W.-M.Yaoetal. (ParticleDataGroup),J.Phys.G33,1(2006)(URL:http://pdg.lbl.gov) 5CHERNIKOV92measuresthephotonmass at1.24K,following atheoreticalsuggestion that electromagnetic gauge invariance might break down at some low critical tempera- ture. See the erratum for a correction, included here, to the published result. 6RYAN 85 measures the photon mass at 1.36 K (see the footnote to CHERNIKOV 92). 7 CHIBISOV 76 depends in critical way on assumptions such as applicability of virial the- orem. Some of the arguments given only in unpublished references. 8 See criticism questioningthe validityof these results in GOLDHABER 71, PARK 71 and KROLL 71. See also review GOLDHABER 71B. γγγγ CCCCHHHHAAAARRRRGGGGEEEE VALUE(e) DOCUMENT ID TECN COMMENT <<<<5555 ××××11110000−−−−33330000 9RAFFELT 94 TOF Pulsar f −f 1 2 • • • We do not use the following data for averages, fits, limits, etc. • • • <8.5×10−17 10SEMERTZIDIS03 Laser light deflection in B-field <2 ×10−28 11COCCONI 92 VLBA radio telescope resolution <2 ×10−32 COCCONI 88 TOF Pulsar f − f TOF 1 2 9 RAFFELT94notesthatCOCCONI88neglectsthefactthatthetimedelayduetodisper- sion byfreeelectronsin theinterstellarmediumhasthesamephoton energydependence as that due to bending of a charged photon in the magnetic field. His limit is based on theassumption thattheentireobserveddispersion isduetophotoncharge. Itisafactor of 200 less stringent than the COCCONI 88 limit. 10 SEMERTZIDIS 03 reports the first laboratory limit on the photon charge in the last 30 years. Straightforward improvements in the apparatus could attain a sensitivity of −20 10 e. 11 See COCCONI 92 for less stringent limits in other frequency ranges. Also see RAF- FELT 94 note. γγγγ RRRREEEEFFFFEEEERRRREEEENNNNCCCCEEEESSSS ACCIOLY 04 PR D69 107501 A. Accioly, R. Paszko GOLDHABER 03 PRL 91 149101 A.S. Goldhaber, M.M. Nieto LUO 03 PRL 90 081801 J. Luo et al. LUO 03B PRL 91 149102 J. Luo et al. SEMERTZIDIS 03 PR D67 017701 Y.K. Semertzidis, G.T. Danby, D.M. Lazarus LAKES 98 PRL 80 1826 R. Lakes (WISC) RYUTOV 97 PPCF 39 A73 D.D. Ryutov (LLNL) FISCHBACH 94 PRL 73 514 E. Fischbach et al. (PURD, JHU+) RAFFELT 94 PR D50 7729 G. Raffelt (MPIM) CHERNIKOV 92 PRL 68 3383 M.A. Chernikov et al. (ETH) Also PRL 69 2999 (erratum) M.A. Chernikov et al. (ETH) COCCONI 92 AJP 60 750 G. Cocconi (CERN) COCCONI 88 PL B206 705 G. Cocconi (CERN) RYAN 85 PR D32 802 J.J. Ryan, F. Accetta, R.H. Austin (PRIN) BYRNE 77 Ast.Sp.Sci. 46 115 J. Byrne (LOIC) CHIBISOV 76 SPU 19 624 G.V. Chibisov (LEBD) DAVIS 75 PRL 35 1402 L. Davis, A.S. Goldhaber, M.M. Nieto (CIT, STON+) HOLLWEG 74 PRL 32 961 J.V. Hollweg (NCAR) FRANKEN 71 PRL 26 115 P.A. Franken, G.W. Ampulski (MICH) GOLDHABER 71 PRL 26 1390 A.S. Goldhaber, M.M. Nieto (STON, BOHR, UCSB) GOLDHABER 71B RMP 43 277 A.S. Goldhaber, M.M. Nieto (STON, BOHR, UCSB) KROLL 71 PRL 26 1395 N.M. Kroll (SLAC) PARK 71 PRL 26 1393 D. Park, E.R. Williams (WILC) WILLIAMS 71 PRL 26 721 E.R. Williams, J.E. Faller, H.A. Hill (WESL) GOLDHABER 68 PRL 21 567 A.S. Goldhaber, M.M. Nieto (STON) PATEL 65 PL 14 105 V.L. Patel (DUKE) GINTSBURG 64 Sov. Astr. AJ7 536 M.A. Gintsburg (ASCI) HTTP://PDG.LBL.GOV Page 2 Created: 7/6/2006 16:35 Citation: W.-M.Yaoetal. (ParticleDataGroup),J.Phys.G33,1(2006)(URL:http://pdg.lbl.gov) g P − I(J ) = 0(1 ) or gluon SU(3) color octet Mass m = 0. Theoretical value. A mass as large as a few MeV may not be precluded, see YNDURAIN 95. VALUE DOCUMENT ID TECN COMMENT • • • We do not use the following data for averages, fits, limits, etc. • • • ABREU 92E DLPH Spin 1, not 0 ALEXANDER 91H OPAL Spin 1, not 0 BEHREND 82D CELL Spin 1, not 0 BERGER 80D PLUT Spin 1, not 0 BRANDELIK 80C TASS Spin 1, not 0 gggglllluuuuoooonnnn RRRREEEEFFFFEEEERRRREEEENNNNCCCCEEEESSSS YNDURAIN 95 PL B345 524 F.J. Yndurain (MADU) ABREU 92E PL B274 498 P. Abreu et al. (DELPHI Collab.) ALEXANDER 91H ZPHY C52 543 G. Alexander et al. (OPAL Collab.) BEHREND 82D PL B110 329 H.J. Behrend et al. (CELLO Collab.) BERGER 80D PL B97 459 C. Berger et al. (PLUTO Collab.) BRANDELIK 80C PL B97 453 R. Brandelik et al. (TASSO Collab.) HTTP://PDG.LBL.GOV Page 1 Created: 7/6/2006 16:34 Citation: W.-M.Yaoetal. (ParticleDataGroup),J.Phys.G33,1(2006)(URL:http://pdg.lbl.gov) graviton J = 2 OMITTED FROM SUMMARY TABLE ggggrrrraaaavvvviiiittttoooonnnn MMMMAAAASSSSSSSS All of the following limits are obtained assuming Yukawa potential in weak field limit. VANDAM 70 argue that a massive field cannot ap- proach general relativity in the zero-mass limit; however, see GOLD- HABER 74 and references therein. h is the Hubble constant in units 0 −1 −1 of 100 kms Mpc . VALUE(eV) DOCUMENT ID COMMENT • • • We do not use the following data for averages, fits, limits, etc. • • • <7 ×10−32 1CHOUDHURY 04 Weak gravitational lensing <7.6×10−20 2FINN 02 Binary Pulsars 3 DAMOUR 91 Binary pulsar PSR 1913+16 <2×10−29 h−1 GOLDHABER 74 Rich clusters 0 <7 ×10−28 HARE 73 Galaxy <8 ×104 HARE 73 2γ decay 1 CHOUDHURY 04 sets limits based on nonobservation of a distortion in the measured values of the variance of the power spectrum. 2 FINN 02 analyze the orbital decay rates of PSRB1913+16 and PSRB1534+12 with a possiblegravitonmassasaparameter. Thecombinedfrequentistmasslimitisat90%CL. 3 DAMOUR 91 is an analysis of the orbital period change in binary pulsar PSR1913+16, and confirms the general relativity prediction to 0.8%. “The theoretical importance of the [rate of orbital period decay] measurement has long been recognized as a direct confirmation that the gravitational interaction propagates with velocity c (which is the immediate cause of the appearance of a damping force in the binary pulsar system) and thereby as a test of the existence of gravitational radiation and of its quadrupolar nature.” TAYLOR93addsthatorbitalparameterstudiesnowagreewithgeneralrelativity to 0.5%, and set limits on the level of scalar contribution in the context of a family of tensor [spin2]-biscalar theories. ggggrrrraaaavvvviiiittttoooonnnn RRRREEEEFFFFEEEERRRREEEENNNNCCCCEEEESSSS CHOUDHURY 04 ASP 21 559 S.R. Choudhury et al. (DELPH, MELB) FINN 02 PR D65 044022 L.S. Finn, P.J. Sutton TAYLOR 93 NAT 355 132 J.N. Taylor et al. (PRIN, ARCBO, BURE+)J DAMOUR 91 APJ 366 501 T. Damour, J.H. Taylor (BURE, MEUD, PRIN) GOLDHABER 74 PR D9 1119 A.S. Goldhaber, M.M. Nieto (LANL, STON) HARE 73 CJP 51 431 M.G. Hare (SASK) VANDAM 70 NP B22 397 H. van Dam, M. Veltman (UTRE) HTTP://PDG.LBL.GOV Page 1 Created: 7/6/2006 16:34 Citation: W.-M.Yaoetal. (ParticleDataGroup),J.Phys.G33,1(2006)(URL:http://pdg.lbl.gov) W J = 1 THE MASS OF THE W BOSON Revised March 2006 by C. Caso (University of Genova) and A. Gurtu (Tata Institute). Till 1995 the production and study of the W boson was the exclusive domain of the pp colliders at CERN and FNAL. W production in these hadron colliders is tagged by a high p lepton from W decay. Owing to unknown parton–parton T effective energy and missing energy in the longitudinal direction, the experiments reconstruct only the transverse mass of the W and derive the W mass from comparing the transverse mass distribution with Monte Carlo predictions as a function of M . W Beginning 1996 the energy of LEP increased to above 161 GeV, the threshold for W–pair production. A precise knowledge of the e+e− center-of-mass energy enables one to reconstruct the W mass even if one of them decays leptonically. At LEP two methods have been used to obtain the W mass. In the first method the measured W–pair production cross sections, σ(e+e− → W+W−), have been used to determine the W mass using the predicted dependence of this cross section on M (see Fig. 1). At 161 GeV, which is just above the W W–pair production threshold, this dependence is a much more sensitive function of the W mass than at the higher energies (172 to 209 GeV) at which LEP has run during 1996–2000. In the second method, which is used at the higher energies, the W mass has been determined by directly reconstructing the W from its decay products. HTTP://PDG.LBL.GOV Page 1 Created: 7/6/2006 16:36 Citation: W.-M.Yaoetal. (ParticleDataGroup),J.Phys.G33,1(2006)(URL:http://pdg.lbl.gov) ) b 20 LEP PRELIMINARY p ( W YFSWW and RacoonWW W σ 18 10 17 16 0 190 195 200 205 160 180 200 √s (GeV) Figure 1: Measurement of the W-pair pro- duction cross section as a function of the center– of–mass energy [1], compared to the predictions of RACOONWW [3] and YFSWW [4]. The shaded area represents the uncertainty on the theoretical predictions, estimated to be ±2% for √ s < 170 GeV and ranging from 0.7 to 0.4% above 170 GeV. See full-color version on color pages at end of book. Each LEP experiment has combined their own mass values properly taking into account the common systematic errors. HTTP://PDG.LBL.GOV Page 2 Created: 7/6/2006 16:36 Citation: W.-M.Yaoetal. (ParticleDataGroup),J.Phys.G33,1(2006)(URL:http://pdg.lbl.gov) In order to compute the LEP average W mass each exper- iment has provided its measured W mass for the qqqq and qq(cid:2)ν channels at each center-of-mass energy along with a de- (cid:1) tailed break-up of errors (statistical and uncorrelated, partially correlated and fully correlated systematics [1]) . These have been properly combined to obtain a preliminary LEP W mass = 80.388±0.035 GeV [2], which includes W mass determina- tion from W-pair producton cross section variation at threshold. Errors due to uncertainties in LEP energy (9 MeV) and possible effect of color reconnection (CR) and Bose–Einstein correlations (BEC) between quarks from different W’s (7 MeV) are included. The mass difference between qqqq and qq(cid:2)ν final states (due to (cid:1) possible CR and BEC effects) is −4 ± 44 MeV. For completeness we give here also the preliminary LEP value for the W width: Γ(W) = 2.134± 0.079 GeV [2]. The two Tevatron experiments have also carried out the exercise of identifying common systematic errors and averag- ing with CERN UA2 data obtain an average W mass [5]= 80.454±0.059 GeV. Combining the above W mass values from LEP and hadron colliders, which are based on all published and unpublished results, and assuming no common systematics between them, yields a preliminary average W mass of 80.405± 0.030 GeV. Finally a fit to this directly determined W mass together with measurements on the ratio of W to Z mass (M /M ) W Z and on their mass difference (M –M ) yields a world average Z W W-boson mass of 80.406± 0.029 GeV. The Standard Model prediction from the electroweak fit, using Z-pole data plus mtop measurement, gives a W–boson mass of 80.364± 0.021 GeV [1,2]. HTTP://PDG.LBL.GOV Page 3 Created: 7/6/2006 16:36 Citation: W.-M.Yaoetal. (ParticleDataGroup),J.Phys.G33,1(2006)(URL:http://pdg.lbl.gov) OUR FIT in the listing below is obtained by combining only published LEP and p–p Collider results using the same procedure as above. References 1. The LEP Collaborations: ALEPH, DELPHI, L3, OPAL, the LEP Electroweak Working Group, CERN-PH-EP/2005- 051, hep-ex/0511027 (9 November 2005). 2. A. Venturi, “New (almost final) W mass and width results from LEP”, talk given at “Les Rencontres de Physique de la Vall´ee d’Aoste”, La Thuile (Italy), 5–11 March 2006. 3. A. Denner et al., Nucl. Phys. B587 67, (2000). 4. S. Jadach et al., Comput. Phys. Comm. 140, 432 (2001). 5. V.M. Abazov et al., Phys. Rev. D70, 092008 (2004). WWWW MMMMAAAASSSSSSSS To obtain the world average, common systematics between experiments are properly taken into account. The LEP average W mass based on published results is 80.383 ± 0.035 GeV. The combined pp collider data yields an average W mass of 80.454 ± 0.059 GeV (ABAZOV 04D). OURFITusestheseaverageLEPandpp colliderW massvaluestogether with the Z mass, the W to Z mass ratio, and mass difference measure- ments. VALUE(GeV) EVTS DOCUMENT ID TECN COMMENT 88880000....444400003333±±±± 0000....000022229999OOOOUUUURRRRFFFFIIIITTTT 80.415± 0.042±0.031 11830 1ABBIENDI 06 OPAL Eecem = 170–209 GeV 80.270± 0.046±0.031 9909 2ACHARD 06 L3 Eecem = 161–209 GeV 80.440± 0.043±0.027 8692 3SCHAEL 06 ALEP Eecem = 161–209 GeV pp 80.483± 0.084 49247 4ABAZOV 02D D0 Ecm= 1.8 TeV 80.359± 0.074±0.049 3077 5ABREU 01K DLPH Eecem= 161+172+183 +189 GeV pp 80.433± 0.079 53841 6AFFOLDER 01E CDF Ecm= 1.8 TeV • • • We do not use the following data for averages, fits, limits, etc. • • • 82.87 ± 1.82 +−00..1360 1500 7AKTAS 06 H1 e±√p → νe(νe)X, s≈300 GeV 80.41 ± 0.41 ±0.13 1101 8ABBIENDI 03C OPAL Repl. by ABBIE√NDI 06 80.3 ± 2.1 ± 1.2 ± 1.0 645 9CHEKANOV 02C ZEUS e−p → νeX, s= 318 GeV 80.432± 0.066±0.045 2789 10ABBIENDI 01F OPAL Repl. by ABBIENDI 06 80.482± 0.091 45394 11ABBOTT 00 D0 Repl. by ABAZOV 02D 80.418± 0.061±0.047 2977 12BARATE 00T ALEP Repl. by SCHAEL 06 HTTP://PDG.LBL.GOV Page 4 Created: 7/6/2006 16:36 Citation: W.-M.Yaoetal. (ParticleDataGroup),J.Phys.G33,1(2006)(URL:http://pdg.lbl.gov) 81.4−+22..67 ± 2.0−+33..03 1086 13BREITWEG 00D ZEUS e+p → νeX, √s ≈ 300 GeV 80.270± 0.137±0.048 809 14ABREU 99T DLPH Repl. by ABREU 01K 80.61 ± 0.15 801 15ACCIARRI 99 L3 Repl. by ACHARD 06 80.41 ± 0.18 8986 16ABE 95P CDF Repl. by AF- FOLDER 01E 80.84 ± 0.22 ±0.83 2065 17ALITTI 92B UA2 See W/Z ratio below pp 80.79 ± 0.31 ±0.84 18ALITTI 90B UA2 Ecm= 546,630 GeV pp 80.0 ± 3.3 ±2.4 22 19ABE 89I CDF Ecm= 1.8 TeV pp 82.7 ± 1.0 ±2.7 149 20ALBAJAR 89 UA1 Ecm= 546,630 GeV 81.8 −+ 56..30 ±2.6 46 21ALBAJAR 89 UA1 Epcmp= 546,630 GeV pp 89 ± 3 ±6 32 22ALBAJAR 89 UA1 Ecm= 546,630 GeV ee 81. ± 5. 6 ARNISON 83 UA1 Ecm= 546 GeV 80. +−160.. 4 BANNER 83B UA2 Repl. by ALITTI 90B 1ABBIENDI 06 use direct reconstruction of the kinematics of W+W− → qq(cid:2)ν(cid:2) and W+W− → qqqq events. The result quoted here is obtained combining this mass value with the results using W+W− → (cid:2)ν(cid:2)(cid:2)(cid:4)ν(cid:2)(cid:3) events in the energy range 183–207 GeV(ABBIENDI03C) andthedependenceoftheWW productioncross-sectiononmW at threshold. The systematic error includes ±0.009 GeV due to the uncertainty on the LEP beam energy. 2ACHARD 06 use direct reconstruction of the kinematics of W+W− → qq(cid:2)ν(cid:2) and W+W− → qqqq events in the C.M. energy range 189–209 GeV. The result quoted here is obtained combining this mass value with the results obtained from a direct W mass reconstruction at 172 and 183 GeV and with those from the dependence of the WW production cross-section on mW at 161 and 172 GeV (ACCIARRI 99). 3SCHAEL 06 use direct reconstruction of the kinematics of W+W− → qq(cid:2)ν(cid:2) and W+W− → qqqq events in the C.M. energy range 183–209 GeV. The result quoted here is obtained combining this mass value with those obtained from the dependence of the W pair production cross-section on mW at 161 and 172 GeV (BARATE 97 and BARATE 97S respectively). The systematic error includes ±0.009 GeV due to possible effects of final state interactions in the qqqq channel and ±0.009 GeV due to the uncertaintyon the LEP beam energy. 4ABAZOV 02D improve the measurement of the W-boson mass including W → eνe eventsinwhichtheelectronisclosetoaboundaryofacentralelectromagneticcalorimeter module. ProperlycombiningtheresultsobtainedbyfittingmT(W),pT(e),andpT(ν), this sample provides a mass value of 80.574 ± 0.405 GeV. The value reported here is a combination of this measurement with all previous DØ W-boson mass measurements. 5ABREU 01K obtain this value properly combining results obtained from a direct W mass reconstruction at 172, 183, and 189 GeV with those from measurements of W- pair production cross sections at 161, 172, and 183 GeV. The systematic error includes ±0.017 GeV due to thebeam energyuncertaintyand ±0.033 GeV due to possible color reconnection and Bose-Einstein effects in the purely hadronic final state. 6AFFOLDER 01E fit the transverse mass spectrum of 30115 W → eνe events (MW= 80.473±0.065±0.092GeV)andof14740W → µνµ events(MW=80.465±0.100± 0.103GeV) obtainedin therunIB(1994-95). Combiningtheelectronandmuonresults, accountingforcorrelateduncertainties,yieldsMW=80.470±0.089GeV.Theycombine this value with their measurement of ABE 95P reported in run IA (1992-93) to obtain the quoted value. 7AKTAS 06 fit the Q2 dependence (300 < Q2 < 30,000 GeV2) of the charged-current differentialcross section with a propagator mass. The first error is experimentaland the second corresponds to uncertainties due to input parameters and model assumptions. HTTP://PDG.LBL.GOV Page 5 Created: 7/6/2006 16:36 Citation: W.-M.Yaoetal. (ParticleDataGroup),J.Phys.G33,1(2006)(URL:http://pdg.lbl.gov) 8ABBIENDI 03C determine the mass of the W boson using fully leptonic decays W+W− → (cid:2)ν(cid:2)(cid:2)(cid:4)ν(cid:2)(cid:3). They use the measured energies of the charged leptons and an approximate kinematic reconstruction of the event (both neutrinos are assumed in the same plane as the charged leptons) to get a W pseudo-mass. All these variables are combined in a simultaneous maximum likelihood fit. The systematic error is dominated by the uncertaintyon the lepton energy. 9CHEKANOV02CfittheQ2 dependence(200<Q2 <60000GeV2)ofthecharged-current differential cross sections with a propagator mass fit. The last error is due to the uncer- tainty on the probability density functions. 10 ABBIENDI 01F obtain this value properly combining results obtained from a direct W mass reconstruction at 172, 183, and 189 GeV with that from measurement of the W-pair productioncrosssection at 161 GeV. Thesystematic errorincludes ±0.017GeV due to LEP energy uncertaintyand ±0.028 GeV due to possible color reconnection and Bose-Einstein effects in the purely hadronic final state. 11ABBOTT 00 use W → eνe events to measure the W mass with a fit to the transverse mass distribution. The result quoted here corresponds to electrons detected both in the forwardandinthecentralcalorimetersforthedatarecordedin1992–1995. Forthelarge rapidity electrons recorded in 1994–1995, the analysis combines results obtained from mT, pT(e), and pT(ν). 12BARATE00TobtainthisvalueproperlycombiningresultsobtainedfromadirectW mass reconstruction at 172, 183, and 189 GeV with those from measurements of W-pair production cross sections at 161 and 172 GeV. The systematic error includes ±0.017 GeV due to LEP energyuncertaintyand ±0.019 GeV due to possible color reconnection and Bose-Einstein effects in the purely hadronic final state. 13BREITWEG 00D fit the Q2 dependence (200<Q2 <22500 GeV2) of the charged- currentdifferentialcross sections witha propagatormass fit. The last error is duetothe uncertaintyon the probability density functions. 14ABREU 99T obtainthis valueproperlycombiningresults obtainedfroma directW mass reconstruction at 172 and 183 GeV with those from measurement of W-pair production crosssectionsat161, 172, and183 GeV. Thesystematic errorincludes ±0.021 GeVdue tothebeam energyuncertaintyand ±0.030 GeV due topossible color reconnectionand Bose-Einstein effects in the purely hadronic final state. 15ACCIARRI99obtainthisvalueproperlycombiningresultsobtainedfromadirectW mass reconstruction at 172 and 183 GeV with those from the measurements of the total W- pairproductioncrosssectionsat161 and172GeV. Thevalueof themassobtainedfrom the direct reconstruction at 172 and 183 GeV is M(W)= 80.58 ± 0.14 ± 0.08 GeV. 16ABE 95P use 3268 W → µνµ events to find M = 80.310 ± 0.205 ± 0.130 GeV and 5718 W → eνe eventstofindM = 80.490±0.145±0.175 GeV. Theresultgiven here combines these while accounting for correlated uncertainties. 17ALITTI 92B res(cid:1)ult has two contributions to the systematic error (±0.83); one (±0.81) cancelsinmW mZ andone(±0.17)isnoncancelling. Thesewereaddedinquadrature. We choose theALITTI 92B valuewithout using the LEPmZ value, because weperform our own combined fit. 18Therearetwocontributionstothesystematicerror(±0.84): one(±0.81)whichcancels inmW/mZ andone(±0.21) whichisnon-cancelling. Thesewereaddedinquadrature. 19 ABE 89I systematic error dominated by the uncertainty in the absolute energy scale. 20ALBAJAR 89 result is from a total sample of 299 W → eν events. 21ALBAJAR 89 result is from a total sample of 67 W → µν events. 22ALBAJAR 89 result is from W → τν events. HTTP://PDG.LBL.GOV Page 6 Created: 7/6/2006 16:36