共查询到20条相似文献,搜索用时 31 毫秒
1.
Eisenstein BI Ernst J Gladding GE Gollin GD Hans RM Johnson E Karliner I Marsh MA Plager C Sedlack C Selen M Thaler JJ Williams J Edwards KW Sadoff AJ Ammar R Bean A Besson D Zhao X Anderson S Frolov VV Kubota Y Lee SJ Poling R Smith A Stepaniak CJ Urheim J Ahmed S Alam MS Athar SB Jian L Ling L Saleem M Timm S Wappler F Anastassov A Eckhart E Gan KK Gwon C Hart T Honscheid K Hufnagel D Kagan H Kass R Pedlar TK Thayer JB von Toerne E Zoeller MM Richichi SJ Severini H Skubic P Undrus A Savinov V 《Physical review letters》2001,87(6):061801
Using 12.7 fb(-1) of data collected with the CLEO detector at CESR, we observed two-photon production of the cc states chi(c0) and chi(c2) in their decay to pi(+)pi(-)pi(+)pi(-). We measured gamma(gammagamma)(chi(c))xB(chi(c)-->pi(+)pi(-)pi(+)pi(-)) to be 75+/-13(stat)+/-8(syst) eV for the chi(c0) and 6.4+/-1.8(stat)+/-0.8(syst) eV for the chi(c2), implying gamma(gammagamma)(chi(c0)) = 3.76+/-0.65(stat)+/-0.41(syst)+/-1.69(br) keV and gamma(gammagamma)(chi(c2)) = 0.53+/-0.15(stat)+/-0.06(syst)+/-0.22(br) keV. Also, cancellation of dominant experimental and theoretical uncertainties permits a precise comparison of gamma(gammagamma)(chi(c0))/gamma(gammagamma)(chi(c2)), evaluated to be 7.4+/-2.4(stat)+/-0.5(syst)+/-0.9(br), with QCD-based predictions. 相似文献
2.
Aubert B Barate R Boutigny D Couderc F Karyotakis Y Lees JP Poireau V Tisserand V Zghiche A Grauges E Palano A Pappagallo M Pompili A Chen JC Qi ND Rong G Wang P Zhu YS Eigen G Ofte I Stugu B Abrams GS Battaglia M Breon AB Brown DN Button-Shafer J Cahn RN Charles E Day CT Gill MS Gritsan AV Groysman Y Jacobsen RG Kadel RW Kadyk J Kerth LT Kolomensky YG Kukartsev G Lynch G Mir LM Oddone PJ Orimoto TJ Pripstein M Roe NA Ronan MT Wenzel WA Barrett M Ford KE Harrison TJ Hart AJ Hawkes CM Morgan SE 《Physical review letters》2007,98(21):211804
We present a measurement of the partial branching fractions and mass spectra of the exclusive radiative penguin processes B-->Kpipigamma in the range m(Kpipi)<1.8 GeV/c(2). We reconstruct four final states: K(+)pi(-)pi(+)gamma, K(+)pi(-)pi(0)gamma, K(S)(0)pi(-)pi(+)gamma, and K(S)(0)pi(+)pi(0)gamma, where K(S)(0)-->pi(+)pi(-). Using 232 x 10(6) e(+)e(-)-->BB events recorded by the BABAR experiment at the SLAC PEP-II asymmetric-energy storage ring, we measure the branching fractions B(B(+)-->K(+)pi(-)pi(+)gamma)=[2.95+/-0.13(stat)+/-0.20(syst)] x 10(-5), B(B(0)-->K(+)pi(-)pi(0)gamma)=[4.07+/-0.22(stat)+/-0.31(syst)] x 10(-5), B(B(0)-->K(0)pi(+)pi(-)gamma)=[1.85+/-0.21(stat)+/-0.12(syst)] x 10(-5), and B(B(+)-->K(0)pi(+)pi(0)gamma)=[4.56+/-0.42(stat)+/-0.31(syst)] x 10(-5). 相似文献
3.
Aubert B Barate R Boutigny D Couderc F Gaillard JM Hicheur A Karyotakis Y Lees JP Tisserand V Zghiche A Palano A Pompili A Chen JC Qi ND Rong G Wang P Zhu YS Eigen G Ofte I Stugu B Abrams GS Borgland AW Breon AB Brown DN Button-Shafer J Cahn RN Charles E Day CT Gill MS Gritsan AV Groysman Y Jacobsen RG Kadel RW Kadyk J Kerth LT Kolomensky YG Kukartsev G LeClerc C Levi ME Lynch G Mir LM Oddone PJ Orimoto TJ Pripstein M Roe NA Ronan MT Shelkov VG Telnov AV Wenzel WA Ford K Harrison TJ Hawkes CM 《Physical review letters》2004,92(24):241802
We study B+/ --> J/psi pi(+/-) and B+/ --> J/psi K+/- decays in a sample of about 89 x 10(6) BB pairs collected with the BABAR detector at the PEP-II asymmetric B factory at SLAC. We observe a signal of 244+/-20 B+/ --> J/psi pi(+/-) events and determine the ratio B(B+/ --> J/psi pi(+/-))/B(B+/ --> J/psi K+/-) to be [5.37+/-0.45(stat)+/-0.11(syst)]%. The charge asymmetries for the B+/ --> J/psi pi(+/-) and B+/ --> J/psi K+/- decays are determined to be A(pi)=0.123+/-0.085(stat)+/-0.004(syst) and A(K)=0.030+/-0.015(stat)+/-0.006(syst), respectively. 相似文献
4.
Aubert B Bona M Boutigny D Couderc F Karyotakis Y Lees JP Poireau V Tisserand V Zghiche A Grauges E Palano A Chen JC Qi ND Rong G Wang P Zhu YS Eigen G Ofte I Stugu B Abrams GS Battaglia M Brown DN Button-Shafer J Cahn RN Charles E Gill MS Groysman Y Jacobsen RG Kadyk JA Kerth LT Kolomensky YG Kukartsev G Lynch G Mir LM Orimoto TJ Pripstein M Roe NA Ronan MT Wenzel WA Sanchez Pdel A Barrett M Ford KE Hart AJ Harrison TJ Hawkes CM Watson AT Held T Koch H Lewandowski B Pelizaeus M Peters K 《Physical review letters》2006,97(26):261803
We report measurements of the decays B(+)-->phiphiK(+) and B(0)-->phiphiK(0) using a sample of 231 x 10(6) BB pairs collected with the BABAR detector at the PEP-II asymmetric-energy B factory at the Stanford Linear Accelerator Center. The branching fractions are measured to be B(B(+)-->phiphiK(+))=(7.5+/-1.0(stat)+/-0.7(syst)) x 10(-6) and B(B(0)-->phiphiK(0))=(4.1(-1.4)(+1.7)(stat)+/-0.4(syst)) x 10(-6) for a phiphi invariant mass below 2.85 GeV/c(2). 相似文献
5.
Coan TE Gao YS Liu F Artuso M Blusk S Butt J Li J Menaa N Mountain R Nisar S Randrianarivony K Redjimi R Sia R Skwarnicki T Stone S Wang JC Zhang K Csorna SE Bonvicini G Cinabro D Dubrovin M Lincoln A Asner DM Edwards KW Briere RA Brock I Chen J Ferguson T Tatishvili G Vogel H Watkins ME Rosner JL Adam NE Alexander JP Berkelman K Cassel DG Duboscq JE Ecklund KM Ehrlich R Fields L Galik RS Gibbons L Gray R Gray SW Hartill DL Heltsley BK Hertz D Jones CD Kandaswamy J Kreinick DL Kuznetsov VE 《Physical review letters》2006,96(16):162003
Using data collected with the CLEO detector operating at the CESR e+e- collider at sqrt[s]=3.97-4.26 GeV, we investigate 15 charmonium decay modes of the psi(4040), psi(4160), and Y(4260) resonances. We confirm, at 11 sigma significance, the BABAR Y(4260)-->pi+pi- J/psi discovery, make the first observation of Y(4260)--> pi(0)pi(0) J/psi (5.1 sigma), and find the first evidence for Y(4260)-->K+K- J/psi(3.7 sigma). We measure e+e- cross sections at sqrt[s]=4.26 GeV as sigma(pi+pi- J/psi)=58(+12)(-10)+/-4 pb, sigma(pi(0)pi(0) J/psi)=23(+12)(-8)+/-1 pb, and sigma(K+K- J/psi)=9(+9)(-5)+/-1 pb, in which the uncertainties are statistical and systematic, respectively. Upper limits are placed on other decay rates from all three resonances. 相似文献
6.
Mikami Y Abe K Abe T Aihara H Akemoto M Asano Y Aso T Aushev T Bahinipati S Bakich AM Ban Y Bay A Bizjak I Bondar A Bozek A Bracko M Browder TE Chao Y Cheon BG Chistov R Choi SK Choi Y Choi YK Chuvikov A Danilov M Dong LY Dragic J Eidelman S Eiges V Fukunaga C Furukawa K Gabyshev N Garmash A Gershon T Gokhroo G Golob B Handa F Hara T Hayashii H Hazumi M Higuchi I Hinz L Hokuue T Hoshi Y Hou WS Huang HC Iijima T Ikeda H Inami K Ishikawa A Iwasaki H Iwasaki M Iwasaki Y Kang JH Kang JS Kapusta P 《Physical review letters》2004,92(1):012002
We report measurements of the properties of the D(+)(sJ)(2317) and D(+)(sJ)(2457) resonances produced in continuum e(+)e(-) annihilation near sqrt[s]=10.6 GeV. The analysis is based on an 86.9 fb(-1) data sample collected with the Belle detector at KEKB. We determine the masses to be M(D(+)(sJ)(2317))=2317.2+/-0.5(stat)+/-0.9(syst) MeV/c(2) and M(D(+)(sJ)(2457))=2456.5+/-1.3(stat)+/-1.3(syst) MeV/c(2). We observe the radiative decay mode D(+)(sJ)(2457)-->D(+)(s)gamma and the dipion decay mode D(+)(sJ)(2457)-->D(+)(s)pi(+)pi(-) and determine their branching fractions. No corresponding decays are observed for the D(sJ)(2317) state. These results are consistent with the spin-parity assignments of 0(+) for the D(sJ)(2317) and 1(+) for the D(sJ)(2457). 相似文献
7.
Ammar R Besson D Zhao X Anderson S Frolov VV Kubota Y Lee SJ Li SZ Poling R Smith A Stepaniak CJ Urheim J Ahmed S Alam MS Jian L Saleem M Wappler F Eckhart E Gan KK Gwon C Hart T Honscheid K Hufnagel D Kagan H Kass R Pedlar TK Thayer JB von Toerne E Wilksen T Zoeller MM Muramatsu H Richichi SJ Severini H Skubic P Dytman SA Nam S Savinov V Chen S Hinson JW Lee J Miller DH Pavlunin V Shibata EI Shipsey IP Cronin-Hennessy D Lyon AL Park CS Park W Thorndike EH Coan TE Gao YS Liu F Maravin Y 《Physical review letters》2002,89(17):171803
Using the CLEO detector at the Cornell Electron Storage Ring we have observed the Omega(0)(c) (css ground state) in the decay Omega(0)(c)-->Omega(-)e(+)nu(e). We find a signal of 11.4+/-3.8(stat) events. The probability that we have observed a background fluctuation is 7.6x10(-5). We measure B(Omega(0)(c)-->Omega(-)e(+)nu(e)).sigma(e(+)e(-)-->Omega(0)(c)X)=(42.2+/-14.1(stat)+/-5.7(syst)) fb and R=[Gamma(Omega(0)(c)-->Omega(-)pi(+))]/[Gamma(Omega(0)(c)-->Omega(-)enu(e))]=00.41+/-0.19(stat)+/-0.04(syst). This is the first statistically significant observation of an individual decay mode of the Omega(0)(c) in e(+)e(-) annihilation and the first example of a baryon decaying via beta emission, where no quarks from the first generation participate in the reaction. 相似文献
8.
Ablikim M Bai JZ Ban Y Bian JG Cai X Chen HF Chen HS Chen HX Chen JC Chen J Chen YB Chi SP Chu YP Cui XZ Dai YS Deng ZY Dong LY Dong QF Du SX Du ZZ Fang J Fang SS Fu CD Gao CS Gao YN Gu SD Gu YT Guo YN Guo YQ Guo ZJ Harris FA He KL He M Heng YK Hu HM Hu T Huang GS Huang XP Huang XT Ji XB Jiang XS Jiao JB Jin DP Jin S Jin Y Lai YF Li G Li HB Li HH Li J Li RY Li SM Li WD Li WG Li XL Li XQ Li YL Liang YF Liao HB Liu CX Liu F Liu F Liu HH Liu HM Liu J Liu JB Liu JP Liu RG Liu ZA Lu F Lu GR Lu HJ 《Physical review letters》2005,95(26):262001
The decay channel J/psi --> gamma(pi)(+)pi(-)eta is analyzed using a sample of 5.8 x 10(7) J/psi events collected with the BESII detector. A resonance, the Chi(1835), is observed in the pi(+)pi(-)eta invariant-mass spectrum with a statistical significance of 7.7 sigma. A fit with a Breit-Wigner function yields a mass M = 1833.7 +/- 6.1(stat) +/- 2.7(syst) MeV/c(2), a width Tau = 67.7 +/- 20.3(stat) +/- 7.7(syst) MeV/c(2), and a product branching fraction B(J/psi --> gammaChi) . B(Chi --> pi(+)pi(-)eta) = [2.2 +/- 0.4(stat) +/- 0.4(syst)] x 10(-4). The mass and width of the Chi(1835) are not compatible with any known meson resonance. Its properties are consistent with expectations for the state that produces the strong pp mass threshold enhancement observed in the J/psi --> gammapp process at BESII. 相似文献
9.
Artuso M Blusk S Butt J Li J Menaa N Mountain R Nisar S Randrianarivony K Sia R Skwarnicki T Stone S Wang JC Zhang K Bonvicini G Cinabro D Dubrovin M Lincoln A Asner DM Edwards KW Naik P Briere RA Ferguson T Tatishvili G Vogel H Watkins ME Rosner JL Adam NE Alexander JP Cassel DG Duboscq JE Ehrlich R Fields L Galik RS Gibbons L Gray R Gray SW Hartill DL Heltsley BK Hertz D Jones CD Kandaswamy J Kreinick DL Kuznetsov VE Mahlke-Krüger H Mohapatra D Onyisi PU Patterson JR Peterson D Pivarski J 《Physical review letters》2007,99(19):191801
Using a 281 pb{-1} data sample collected at the psi(3770) with the CLEO-c detector, we present the first absolute branching fraction measurement of the decay D0-->K(-)pi(+)pi(-)e(+)nu(e) at a statistical significance of about 4.0 standard deviations. We find 10 candidates consistent with the decay D0-->K(-)pi(+)pi(-)e(+)nu(e). The probability that a background fluctuation accounts for this signal is less than 4.1 x 10{-5}. We find B(D0-->K(-)pi(+)pi(-)e(+)nu(e)) = [2.8{-1.1}{+1.4}(stat)+/-0.3(syst)]x10{-4}. By restricting the invariant mass of the hadronic system to be consistent with K1(1270), we obtain the product of branching fractions B(D{0}-->K{1}{-}(1270)e{+}nu{e})xB(K1-(1270)-->K{-}pi{+}pi{-})=[2.5{-1.0}{+1.3}(stat)+/-0.2(syst)]x10{-4}. Using B(K1-(1270)-->K{-}pi{+}pi{-})=(33+/-3)%, we obtain B(D{0}-->K{1}{-}(1270)e{+}nu{e})=[7.6{-3.0}{+4.1}(stat)+/-0.6(syst)+/-0.7]x10{-4}. The last error accounts for the uncertainties in the measured K1-(1270)-->K{-}pi{+}pi{-} branching fractions. 相似文献
10.
Chao Y Chang P Abe K Abe K Abe N Adachi I Aihara H Akai K Akatsu M Akemoto M Asano Y Aso T Aulchenko V Aushev T Aziz T Bahinipati S Bakich AM Ban Y Barbero M Bay A Bedny I Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Brodzicka J Browder TE Chang MC Chen A Chen KF Chen WT Cheon BG Chistov R Choi SK Choi Y Choi YK Chuvikov A Cole S Danilov M Dash M Dong LY Dowd R Dragic J Drutskoy A Eidelman S Eiges V Enari Y Epifanov D Everton CW Fang F Flanagan J Fratina S Fujii H Funakoshi Y Furukawa K 《Physical review letters》2004,93(19):191802
We report evidence for direct CP violation in the decay B0-->K+pi(-) with 253 fb(-1) of data collected with the Belle detector at the KEKB e(+)e(-) collider. Using 275x10(6) BB pairs we observe a B-->K+/-pi(-/+) signal with 2140+/-53 events. The measured CP violating asymmetry is A(CP)(K+pi(-))=-0.101+/-0.025(stat)+/-0.005(syst), corresponding to a significance of 3.9sigma including systematics. We also search for CP violation in the decays B+-->K+pi(0) and B+-->pi(+)pi(0). The measured CP violating asymmetries are A(CP)(K+pi(0))=0.04+/-0.05(stat)+/-0.02(syst) and A(CP)(pi(+)pi(0))=-0.02+/-0.10(stat)+/-0.01(syst), corresponding to the intervals -0.05相似文献
11.
Aubert B Boutigny D Gaillard JM Hicheur A Karyotakis Y Lees JP Robbe P Tisserand V Zghiche A Palano A Pompili A Chen JC Qi ND Rong G Wang P Zhu YS Eigen G Ofte I Stugu B Abrams GS Borgland AW Breon AB Brown DN Button-Shafer J Cahn RN Charles E Gill MS Gritsan AV Groysman Y Jacobsen RG Kadel RW Kadyk J Kerth LT Kolomensky YG Kral JF LeClerc C Levi ME Lynch G Mir LM Oddone PJ Orimoto TJ Pripstein M Roe NA Romosan A Ronan MT Shelkov VG Telnov AV Wenzel WA Harrison TJ Hawkes CM Knowles DJ 《Physical review letters》2003,90(18):181803
We report evidence for the decays B0-->D(+)(s)pi(-) and B0-->D(-)(s)K+ and the results of a search for B0-->D(*+)(s)pi(-) and B0-->D(*-)(s)K+ in a sample of 84 x 10(6) upsilon(4S) decays into BB pairs collected with the BABAR detector at the PEP-II asymmetric-energy e(+)e(-) storage ring. We measure the branching fractions B(B0-->D(+)(s)pi(-))=[3.2+/-0.9(stat)+/-1.0(syst)] x 10(-5) and B(B0-->D(-)(s)K+)=[3.2+/-1.0(stat)+/-1.0(syst)] x 10(-5). We also set 90% C.L. limits B(B0-->D(*+)(s)pi(-))<4.1 x 10(-5) and B(B0-->D(*-)(s)K+)<2.5 x 10(-5). 相似文献
12.
Aubert B Barate R Boutigny D Gaillard JM Hicheur A Karyotakis Y Lees JP Robbe P Tisserand V Zghiche A Palano A Pompili A Chen JC Qi ND Rong G Wang P Zhu YS Eigen G Ofte I Stugu B Abrams GS Borgland AW Breon AB Brown DN Button-Shafer J Cahn RN Charles E Gill MS Gritsan AV Groysman Y Jacobsen RG Kadel RW Kadyk J Kerth LT Kolomensky YG Kral JF Kukartsev G LeClerc C Levi ME Lynch G Mir LM Oddone PJ Orimoto TJ Pripstein M Roe NA Romosan A Ronan MT Shelkov VG Telnov AV Wenzel WA Harrison TJ Hawkes CM 《Physical review letters》2003,91(6):061802
We present the first study of the time-dependent CP-violating asymmetry in B0-->J/psi pi(0) decays using e(+)e(-) annihilation data collected with the BABAR detector at the Upsilon(4S) resonance during the years 1999-2002 at the PEP-II asymmetric-energy B Factory at SLAC. Using approximately 88 x 10(6) BB; pairs, our results for the coefficients of the cosine and sine terms of the CP asymmetry are C(J/psi pi(0))=0.38+/-0.41(stat)+/-0.09(syst) and S(J/psi pi(0))=0.05+/-0.49(stat)+/-0.16(syst). 相似文献
13.
《Physical review letters》2007,99(2):021603
We report observations of CP violation in the decays B(0) --> K(+)pi(-) and B(0) --> pi(+)pi(-) in a sample of 383 x 10(6) Upsilon(4S) --> BB[over] events. We find 4372+/-82 B(0) --> K(+)pi(-) decays and measure the direct CP-violating charge asymmetry A(Kpi) = -0.107+/-0.018(stat)(-0.004)(+0.007)(syst), which excludes the CP-conserving hypothesis with a significance of 5.5 standard deviations. In the same sample, we find 1139+/-49 B(0) --> pi(+)pi(-) decays and measure the CP-violating asymmetries S(pipi) = -0.60+/-0.11(stat)+/-0.03(syst) and C(pipi) = -0.21+/-0.09(stat)+/-0.02(syst). CP conservation in B(0) --> pi(+)pi(-) (S(pipi) = C(pipi) = 0) is excluded at a confidence level 1-C.L. = 8 x 10(-8), corresponding to 5.4 standard deviations. 相似文献
14.
Aubert B Barate R Boutigny D Couderc F Gaillard JM Hicheur A Karyotakis Y Lees JP Tisserand V Zghiche A Palano A Pompili A Chen JC Qi ND Rong G Wang P Zhu YS Eigen G Ofte I Stugu B Abrams GS Borgland AW Breon AB Brown DN Button-Shafer J Cahn RN Charles E Day CT Gill MS Gritsan AV Groysman Y Jacobsen RG Kadel RW Kadyk J Kerth LT Kolomensky YG Kukartsev G LeClerc C Lynch G Merchant AM Mir LM Oddone PJ Orimoto TJ Pripstein M Roe NA Ronan MT Shelkov VG Wenzel WA Ford K Harrison TJ Hawkes CM 《Physical review letters》2004,93(8):081802
We measure the branching fraction for the flavor-changing neutral-current process B-->X(s)l(+)l(-) with a sample of 89x10(6) Upsilon(4S)-->BBmacr; events recorded with the BABAR detector at the PEP-II e(+)e(-) storage ring. The final state is reconstructed from e(+)e(-) or micro(+)micro(-) pairs and a hadronic system X(s) consisting of one K+/- or K(0)(S) and up to two pions, with at most one pi(0). We observe a signal of 40+/-10(stat)+/-2(syst) events and extract the inclusive branching fraction B(B-->X(s)l(+)l(-))=(5.6+/-1.5(stat)+/-0.6(exp syst)+/-1.1(model syst))x10(-6) for ml(+)(l(-))>0.2 GeV/c(2). 相似文献
15.
Cronin-Hennessy D Lyon AL Thorndike EH Savinov V Coan TE Fadeyev V Gao YS Maravin Y Narsky I Stroynowski R Ye J Wlodek T Artuso M Ayad R Boulahouache C Bukin K Dambasuren E Karamov S Majumder G Moneti GC Mountain R Schuh S Skwarnicki T Stone S Wang JC Wolf A Wu J Kopp S Kostin M Mahmood AH Csorna SE Danko I McLean KW Xu Z Godang R Bonvicini G Cinabro D Dubrovin M McGee S Zhou GJ Lipeles E Pappas SP Schmidtler M Shapiro A Sun WM Weinstein AJ Würthwein F Jaffe DE Masek G Paar HP Potter EM Prell S 《Physical review letters》2001,86(17):3730-3734
The CLEO experiment at the CESR collider has used 13.7 fb(-1) of data to search for the production of the Omega(0)(c) (css ground state) in e(+)e(-) collisions at square root of (s) approximately 10.6 GeV. The modes used to study the Omega(0)(c) are Omega(-)pi(+), Omega(-)pi(+)pi(0), Xi-K-pi(+)pi(+), Xi0K-pi(+), and Omega(-)pi(+)pi(+)pi(-). We observe a signal of 40.4+/-9.0(stat) events at a mass of 2694.6+/-2.6(stat)+/-1.9(syst) MeV/c(2), for all modes combined. 相似文献
16.
Abazov VM Abbott B Abolins M Acharya BS Adams M Adams T Aguilo E Ahn SH Ahsan M Alexeev GD Alkhazov G Alton A Alverson G Alves GA Anastasoaie M Ancu LS Andeen T Anderson S Andrieu B Anzelc MS Aoki M Arnoud Y Arov M Arthaud M Askew A Asman B Assis Jesus AC Atramentov O Avila C Ay C Badaud F Baden A Bagby L Baldin B Bandurin DV Banerjee P Banerjee S Barberis E Barfuss AF Bargassa P Baringer P Barreto J Bartlett JF Bassler U Bauer D Beale S Bean A Begalli M Begel M Belanger-Champagne C 《Physical review letters》2008,100(21):211802
We present a search for direct CP violation in B(+/-)-->J/psiK(+/-)(pi(+/-)) decays. The event sample is selected from 2.8 fb(-1) of pp collisions recorded by D0 experiment in run II of the Fermilab Tevatron Collider. The charge asymmetry A_(CP)(B(+)-->J/psiK(+))= + 0.0075 +/- 0.0061(stat)+/-0.0030(syst) is obtained using a sample of approximately 40, 000 B(+/-)-->J/psiK(+/-) decays. The achieved precision is of the same level as the expected deviation predicted by some extensions of the standard model. We also measured the charge asymmetry A(CP)(B(+)-->J/psipi(+))=-0.09+/-0.08(stat)+/-0.03(syst). 相似文献
17.
Aubert B Bona M Boutigny D Karyotakis Y Lees JP Poireau V Prudent X Tisserand V Zghiche A Garra Tico J Grauges E Lopez L Palano A Pappagallo M Eigen G Stugu B Sun L Abrams GS Battaglia M Brown DN Button-Shafer J Cahn RN Groysman Y Jacobsen RG Kadyk JA Kerth LT Kolomensky YG Kukartsev G Lopes Pegna D Lynch G Mir LM Orimoto TJ Osipenkov IL Ronan MT Tackmann K Tanabe T Wenzel WA Del Amo Sanchez P Hawkes CM Watson AT Koch H Schroeder T Walker D Asgeirsson DJ Cuhadar-Donszelmann T Fulsom BG Hearty C 《Physical review letters》2008,100(6):061803
We measure time-integrated CP-violating asymmetries of neutral charmed mesons in the modes D0 --> K(-) K(+) and D0 --> pi(-) pi(+) with the highest precision to date by using D0 --> K(-) pi(+) decays to correct detector asymmetries. An analysis of 385.8 fb(-1) of data collected with the BABAR detector yields values of a(CP)(KK)=(0.00+/-0.34(stat)+/-0.13(syst))% and a(CP)(pipi)=(-0.24+/-0.52(stat)+/-0.22(syst))%, which agree with standard model predictions. 相似文献
18.
Ablikim M Bai JZ Ban Y Bian JG Cai X Chen HF Chen HS Chen HX Chen JC Chen J Chen YB Chi SP Chu YP Cui XZ Dai YS Diao LY Deng ZY Dong QF Du SX Fang J Fang SS Fu CD Gao CS Gao YN Gu SD Gu YT Guo YN Guo YQ Guo ZJ Harris FA He KL He M Heng YK Hu HM Hu T Huang GS Huang XT Ji XB Jiang XS Jiang XY Jiao JB Jin DP Jin S Jin Y Lai YF Li G Li HB Li HH Li J Li RY Li SM Li WD Li WG Li XL Li XN Li XQ Li YL Liang YF Liao HB Liu BJ Liu CX Liu F Liu F Liu HH Liu HM Liu J Liu JB Liu JP Liu Q Liu RG Liu ZA Lou YC 《Physical review letters》2006,96(16):162002
An enhancement near threshold is observed in the omega(phi) invariant mass spectrum from the doubly Okubo-Zweig-Iizuka-suppressed decays of J/psi-->gamma(omega)phi, based on a sample of 5.8 x 10(7) J/psi events collected with the BESII detector. A partial wave analysis shows that this enhancement favors JP=0+, and its mass and width are M=1812(+19)(-26)(stat)+/-18(syst) MeV/c2 and Gamma=105+/-20(stat)+/-28(syst) MeV/c2. The product branching fraction is determined to be B(J/psi-->gammaX)B(X-->omega(phi))=[2.61+/-0.27(stat)+/-0.65(syst)]x10(-4). 相似文献
19.
Toyoda H Trischuk W de Troconiz JF Truitt S Tseng J Turini N Ukegawa F Valls J Vejcik S Velev G Vidal R Vilar R Vologouev I Vucinic D Wagner RG Wagner RL Wahl J Wallace NB Walsh AM Wang C Wang CH Wang MJ Watanabe T Waters D Watts T Webb R 《Physical review letters》2000,84(10):2094-2099
We have reconstructed the radiative decays chi(b)(1P)-->Upsilon(1S)gamma and chi(b)(2P)-->Upsilon(1S)gamma in p&pmacr; collisions at sqrt[s] = 1.8 TeV, and measured the fraction of Upsilon(1S) mesons that originate from these decays. For Upsilon(1S) mesons with p(Upsilon)(T)>8.0 GeV/c, the fractions that come from chi(b)(1P) and chi(b)(2P) decays are [27.1+/-6.9(stat)+/-4. 4(syst)]% and [10.5+/-4.4(stat)+/-1.4(syst)]%, respectively. We have derived the fraction of directly produced Upsilon(1S) mesons to be [50.9+/-8.2(stat)+/-9.0(syst)]%. 相似文献
20.
Ushiroda Y Sumisawa K Hazumi M Abe K Abe K Adachi I Aihara H Asano Y Aulchenko V Aushev T Bakich AM Bay A Bedny I Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Brodzicka J Browder TE Chang MC Chang P Chao Y Chen A Chen KF Chen WT Cheon BG Choi SK Choi Y Chuvikov A Cole S Dalseno J Danilov M Dash M Dragic J Eidelman S Fang F Fratina S Gabyshev N Gershon T Gokhroo G Gorisek A Haba J Hara K Hastings NC Hayasaka K Hayashii H Higuchi T Hinz L Hokuue T Hoshi Y Hou S Hou WS Hsiung YB Iijima T 《Physical review letters》2005,94(23):231601
We present a new measurement of CP-violation parameters in B(0)-->K(0)(S)pi(0)gamma decay based on a sample of 275 x 10(6) BB pairs collected at the Gamma(4S) resonance with the Belle detector at the KEKB energy-asymmetric e(+)e(-) collider. One of the B mesons is fully reconstructed in the B(0)-->K(0)(S)pi(0)gamma decay. The flavor of the accompanying B meson is identified from its decay products. CP-violation parameters are obtained from the asymmetry in the distribution of the proper time intervals between the two B decays. We obtain SK(0)(S)(pi(0)gamma) = -0.58(+0.46)(-0.38)(stat) +/- 0.11(syst) and AK(0)(S)(pi(0)gamma) = +0.03 +/- 0.34(stat) +/- 0.11(syst), for the K(0)(S)pi(0) invariant mass covering the full range up to 1.8 GeV/c2. We also measure the CP-violation parameters for the case B(0)-->K(*0)(-->K(0)(S)pi(0))gamma and obtain S(K(*0)gamma) = -0.79(+0.63)(-0.50)(stat) +/- 0.10(syst) for A(K(*0)gamma) fixed at 0. 相似文献