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521.
Abe K Abe K Abe T Adachi I Ahn BS Aihara H Akai K Akatsu M Akemoto M Asano Y Aso T Aulchenko V Aushev T Bakich AM Ban Y Banerjee S Bay A Bedny I Bizjak I Bondar A Bozek A Bracko M Browder TE Chao Y Chen KF Cheon BG Chistov R Choi SK Choi Y Choi YK Chuvikov A Danilov M Dong LY Drutskoy A Eidelman S Eiges V Enari Y Flanagan J Fukunaga C Furukawa K Gabyshev N Garmash A Gershon T Guo R Haba J Hagner C Handa F Hayashii H Hazumi M Hokuue T Hoshi Y Hou WS Huang HC Iijima T Ikeda H Inami K Ishikawa A 《Physical review letters》2004,92(17):171802
We have performed a search for the lepton-flavor-violating decay tau-->microgamma using a data sample of 86.3 fb(-1) accumulated by the Belle detector at KEK. No evidence for a signal is seen, and we set an upper limit for the branching fraction of B(tau-->microgamma)<3.1 x 10(-7) at the 90% confidence level. 相似文献
522.
Wang MZ Abe K Abe K Abe T Adachi I Aihara H Asano Y Aso T Aulchenko V Aushev T Bakich AM Bay A Bizjak I Bondar A Bozek A Bracko M Browder TE Chang MC Chang P Chao Y Chen KF Cheon BG Chistov R Choi SK Choi Y Choi YK Chu PH Chuvikov A Danilov M Dong LY Drutskoy A Eidelman S Eiges V Fukunaga C Gabyshev N Garmash A Gershon T Gokhroo G Golob B Hara T Hayashii H Hazumi M Hokuue T Hoshi Y Hou WS Huang HC Inami K Ishikawa A Itoh R Iwasaki H Iwasaki M Iwasaki Y Kang JH Katayama N Kawai H Kawasaki T 《Physical review letters》2004,92(13):131801
We report the first observation of a b-->u type charmless baryonic B decay, B+-->pppi(+), as well as b-->s type B0-->ppK0 and B+-->ppK(*+) decays. The analysis is based on a 78 fb(-1) data sample recorded on the Upsilon(4S) resonance with the Belle detector at KEKB. We find B(B+-->pppi(+))=(3.06(+0.73)(-0.62)+/-0.37)x10(-6), B(B0-->ppK0)=(1.88(+0.77)(-0.60)+/-0.23)x10(-6), and B(B+-->ppK(*+))=(10.3(+3.6+1.3)(-2.8-1.7))x10(-6). We also update B(B+-->ppK+)=(5.66(+0.67)(-0.57)+/-0.62)x10(-6) and present an upper limit on B(B0-->ppK(*0)) at the 90% confidence level. A common feature of the observed decay modes is threshold peaking in baryon pair invariant mass. 相似文献
523.
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
524.
Sarangi TR Abe K Abe K Abe T Aihara H Asano Y Aulchenko V Aushev T Bahinipati S Bakich AM Ban Y Banerjee S Bitenc U Bizjak I Blyth S Bondar A Bracko M Browder TE Chang MC Chang P Chen KF Cheon BG Chistov R Choi SK Choi Y Chuvikov A Cole S Danilov M Dash M Dong LY Drutskoy A Eidelman S Eiges V Fratina S Gabyshev N Garmash A Gershon T Gokhroo G Haba J Hara K Hastings NC Hayashii H Hazumi M Higuchi T Hinz L Hokuue T Hoshi Y Hou WS Inami K Ishikawa A Ishino H Itoh R Iwasaki H Iwasaki M Kang JH 《Physical review letters》2004,93(3):031802
We report measurements of time dependent decay rates for B0(B(0))-->D((*)-/+)pi(+/-) decays and extraction of CP violation parameters containing phi(3). Using fully reconstructed D((*))pi events from a 140 fb(-1) data sample collected at the Upsilon(4S) resonance, we obtain the CP violation parameters for D(*)pi and Dpi decays, 2R(D((*))pi)sin((2phi(1)+phi(3)+/-delta(D((*))pi)), where R(D((*))pi) is the ratio of the magnitudes of the doubly Cabibbo-suppressed and Cabibbo-favored amplitudes, and delta(D((*))pi) is the strong phase difference between them. Under the assumption of delta(D((*))pi) being close to either 0 degrees or 180 degrees, we obtain |2R(D(*)pi)sin((2phi(1)+phi(3))|=0.060+/-0.040(stat)+/-0.019(syst) and |2R(Dpi)sin((2phi(1)+phi(3))|=0.061+/-0.037(stat)+/-0.018(syst). 相似文献
525.
Abe K Abe K Abe N Abe T Adachi I Aihara H Akai K Akatsu M Akemoto M Asano Y Aso T Aulchenko V Aushev T Bakich AM Ban Y Banerjee S Bay A Bedny I Bizjak I Bondar A Bozek A Bracko M Browder TE Chao Y Chen KF Cheon BG Chistov R Choi SK Choi Y Chuvikov A Cole S Danilov M Dragic J Drutskoy A Eidelman S Eiges V Enari Y Epifanov D Flanagan J Furukawa K Gabyshev N Garmash A Gershon T Golob B Haba J Hara K Hastings NC Hayashii H Hazumi M Hinz L Hokuue T Hoshi Y Hou WS Hsiung YB Huang HC Iijima T Ikeda H 《Physical review letters》2004,93(2):021601
We report the first observation of CP violation in B0-->pi(+)pi(-) decays based on 152x10(6) gamma (4S)-->BB decays collected with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. We reconstruct a B0-->pi(+)pi(-) CP eigenstate and identify the flavor of the accompanying B meson from its decay products. From the distribution of the time intervals between the two B meson decay points, we obtain A(pipi)=+0.58+/-0.15(stat)+/-0.07(syst) and S(pipi)=-1.00+/-0.21(stat)+/-0.07(syst). We rule out the CP-conserving case, A(pipi)=S(pipi)=0, at a level of 5.2 standard deviations. We also find evidence for direct CP violation with a significance at or greater than 3.2 standard deviations for any S(pipi) value. 相似文献
526.
Chistov R Abe K Abe K Abe T Aihara H Akatsu M Asano Y Aushev T Bakich AM Ban Y Banerjee S Bay A Bedny I Bizjak I Bondar A Bozek A Bracko M Brodzicka J Browder TE Chao Y Chen KF Cheon BG Choi Y Choi YK Danilov M Dash M Dong LY Drutskoy A Eidelman S Eiges V Epifanov D Gabyshev N Garmash A Gershon T Golob B Guo R Haba J Hara T Hayashii H Hazumi M Hinz L Hokuue T Hoshi Y Hou WS Huang HC Iijima T Inami K Ishikawa A Iwasaki H Iwasaki M Kagan R Kang JH Kang JS Kapusta P Katayama N Kawai H Kawasaki T 《Physical review letters》2004,93(5):051803
We report the first observation of the decay B+-->psi(3770)K+ where the psi(3770) is reconstructed in the D0(-)D(0) and D+D- decay channels. The obtained branching fraction is B(B+-->psi(3770)K+)=(0.48+/-0.11+/-0.07)x10(-3). We have measured the branching fraction for the decay B+-->D0(-)D0K+ to be (1.17+/-0.21+/-0.15)x10(-3) and set a 90% confidence level upper limit of 0.90 x 10(-3) for the decay B+-->D+D-K+. We also present the results of a search for possible decays to D(-)D and D0(-)D(0)pi(0) of the recently observed X(3872) particle. The analysis is based on 88 fb(-1) of data collected at the Upsilon(4S) resonance by the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. 相似文献
527.
Fujioka S Nishimura H Nishihara K Sasaki A Sunahara A Okuno T Ueda N Ando T Tao Y Shimada Y Hashimoto K Yamaura M Shigemori K Nakai M Nagai K Norimatsu T Nishikawa T Miyanaga N Izawa Y Mima K 《Physical review letters》2005,95(23):235004
Opacity effects on extreme ultraviolet (EUV) emission from laser-produced tin (Sn) plasma have been experimentally investigated. An absorption spectrum of a uniform Sn plasma generated by thermal x rays has been measured in the EUV range (9-19 nm wavelength) for the first time. Experimental results indicate that control of the optical depth of the laser-produced Sn plasma is essential for obtaining high conversion to 13.5 nm-wavelength EUV radiation; 1.8% of the conversion efficiency was attained with the use of 2.2 ns laser pulses. 相似文献
528.
Chen KF Abe K Abe K Aihara H Asano Y Aulchenko V Aushev T Bahinipati S Bakich AM 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 WT Cheon BG Chistov R Choi SK Choi Y Chuvikov A Dalseno J Danilov M Dash M Drutskoy A Eidelman S Enari Y Fang F Fratina S Gabyshev N Garmash A Gershon T Gokhroo G Golob B Gorisek A Haba J Hastings NC Hayasaka K Hayashii H Hazumi M Hinz L Hokuue T Hoshi Y Hou S Hou WS Hsiung YB Iijima T Imoto A 《Physical review letters》2005,94(22):221804
We present measurements of decay amplitudes and triple-product correlations in B-->phiK* decays based on 253 fb(-1) of data recorded at the Upsilon(4S) resonance with the Belle detector at the KEKB e(+)e(-) storage ring. The decay amplitudes for the three different helicity states are determined from the angular distributions of final-state particles. The longitudinal polarization amplitudes are found to be 0.45 +/- 0.05 +/- 0.02 for B0-->phiK(*0) and 0.52 +/- 0.08 +/- 0.03 for B+ -->phiK(*+) decays. CP- and T-odd CP-violating triple-product asymmetries are measured to be consistent with zero. 相似文献
529.
Yang H Nakao M Abe K Abe K Aihara H Asano Y Aushev T Bahinipati S Bakich AM Ban Y 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 WT Cheon BG Chistov R Choi SK Choi Y Choi YK Chuvikov A Cole S Dalseno J Dash M Eidelman S Enari Y Fang F Gabyshev N Garmash A Gershon T Gokhroo G Golob B Haba J Hayasaka K Hayashii H Hazumi M Hinz L Hokuue T Hoshi Y Hsiung YB Iijima T Imoto A Inami K Iwasaki Y Kang JH Kang JS Kataoka SU 《Physical review letters》2005,94(11):111802
We report the observation of the radiative decay B+-->K1(1270)(+) gamma using a data sample of 140 fb(-1) taken at the Upsilon(4S) resonance with the Belle detector at the KEKB e+e- collider. We find the branching fraction to be B(B+-->K1(1270)(+)gamma)=(4.3+/-0.9(stat.)+/-0.9(syst.))x10(-5) with a significance of 7.3sigma. We find no significant signal for B+-->K1(1400)(+)gamma and set an upper limit B(B+-->K1(1400)(+)gamma)<1.5 x 10(-5) at the 90% confidence level. We also measure inclusive branching fractions for B+-->K+pi+pi-gamma and B0-->K0pi+pi-gamma in the mass range 1 GeV/c(2)相似文献
530.
Mibe T Chang WC Nakano T Ahn DS Ahn JK Akimune H Asano Y Daté S Ejiri H Fujimura H Fujiwara M Hicks K Hotta T Imai K Ishikawa T Iwata T Kawai H Kim ZY Kino K Kohri H Kumagai N Makino S Matsuda T Matsumura T Matsuoka N Miwa K Miyabe M Miyachi Y Morita M Muramatsu N Niiyama M Nomachi M Ohashi Y Ooba T Ohkuma H Oshuev DS Rangacharyulu C Sakaguchi A Sasaki T Shagin PM Shiino Y Shimizu H Sugaya Y Sumihama M Titov AI Toi Y Toyokawa H Wakai A Wang CW Wang SC Yonehara K Yorita T Yoshimura M Yosoi M 《Physical review letters》2005,95(18):182001
Photoproduction of a phi meson on protons was studied by means of linearly polarized photons at forward angles in the low-energy region from threshold to Egamma = 2.37 GeV. The differential cross sections at t = -|t|min do not increase smoothly as Egamma increases but show a local maximum at around 2.0 GeV. The angular distributions demonstrate that phi mesons are photoproduced predominantly by helicity-conserving processes, and the local maximum is not likely due to unnatural-parity processes. 相似文献