Search

Your search keyword '"K. Neichi"' showing total 125 results
Start Over Author "K. Neichi"
125 results on '"K. Neichi"'

1. Measurement of the Michel parameters (η‾, ξκ ) in the radiative leptonic decay of τ

Author

J. E. Fast, D. Dossett, M. Niiyama, L. Pesántez, V. Trusov, Andrey Sokolov, S. Shinomiya, Byeong Rok Ko, M. Feindt, I. Nakamura, V. Babu, Hui Li, Jingxu Wang, T. Aushev, O. Frost, Z. Suzuki, J. Grygier, J. H. Kang, Y. Miyachi, Hikaru Kawai, M. Belhorn, Benjamin Schwenker, T. Zivko, Y. B. Hsiung, K. Neichi, A. Zupanc, C. C. Zhang, E. Nakano, Antonio Limosani, T. Ferber, D. H. Lee, H. Kakuno, H. Shibuya, M. Watanabe, L. S. Peak, C. Niebuhr, O. Nitoh, K. Nishimura, Chawon Park, A. Loos, J. C. Dingfelder, M. V. Purohit, P. Goldenzweig, Rupert Leitner, V. V. Zhulanov, J. Yamaoka, Xiuwan Li, K. Senyo, S. Eidelman, L. Shang, Ihn Sik Seong, S. Sandilya, K. Ueno, M. Heck, M. J. Kim, T. Kawasaki, P. Pakhlov, W. Ostrowicz, U. Tamponi, Anton Poluektov, T. Schlüter, S. Sugihara, M. Starič, Y. Igarashi, M. Masuda, Dipanwita Dutta, A. Sugiyama, T. Kumita, M. Uchida, X. H. He, D. Cinabro, Philip Lewis, G. B. Mohanty, C. H. Li, Massimo Berger, B. H. Kim, Y. Yook, H. Yamamoto, L. K. Li, V.N. Zhilich, Y. Kato, V. Chobanova, Y. Kuroki, Satoshi Tanaka, D. Liventsev, Y. Arita, I. Jaegle, K. Miyabayashi, M. Lubej, G. Inguglia, I. Badhrees, Y. Koga, E. Nedelkovska, F. Breibeck, H. Park, J. Stypula, C. Kiesling, E. J. White, A. Bozek, P. Chang, G. S. Varner, Y.-T. Lai, K. Suzuki, P. Schonmeier, M. Iwabuchi, R. Mussa, H. B. Jeon, O. Grzymkowska, C. H. Wang, M. Grosse Perdekamp, R. Itoh, Jung-Hyun Kim, S. Wehle, T. Keck, S. Paul, L. Li Gioi, Y. Yamashita, C. Z. Yuan, Yukinori Sato, J. G. Shiu, M. Nayak, T. Bloomfield, A. Ishikawa, A. Drutskoy, S. E. Vahsen, A. Bay, C.-L. Hsu, T. Saito, S. Rummel, T. Matsuda, Yu Nakahama, M. Tanaka, T. Peng, G. Schnell, A. Rostomyan, Tsukasa Aso, P. Wang, H. Miyata, Y. Hoshi, M. Barrett, B. Bhuyan, Y.L. Han, A. Frey, H. Ye, P. Križan, T. Iijima, Jun Sasaki, H. G. Moser, M. Bračko, Y. Iwasaki, B. G. Fulsom, Peter Kodys, W. W. Jacobs, T. E. Browder, Y. J. Kwon, K. Nakamura, Ya-Qiu Jin, P. Hamer, K. Hayasaka, A. Bobrov, H. Hayashii, Hyunyong Kim, O. Schneider, K. Prasanth, M. Imamura, T. Nagamine, K. Trabelsi, P. Katrenko, T. Müller, J. Klucar, K. T. Kim, C. P. Shen, S. Di Carlo, Seok Kim, S. Okuno, B. Shwartz, Jamal Rorie, D. Getzkow, C. B. Van Hulse, I. Adachi, A. Ogawa, K. Negishi, T. Kuhr, D. Z. Besson, E. Ribežl, D. Santel, Phillip Urquijo, N. Sasao, Victoria Zhukova, V. Savinov, M. Danilov, H. Nakayama, D. Y. Kim, R. Gillard, R. Mizuk, Eberhard Widmann, J. F. Strube, Matthew Jones, M. Z. Wang, K. Kinoshita, M. Yamauchi, G. Bonvicini, Y. B. Li, Y. Teramoto, I. Tikhomirov, D. Mohapatra, J. B. Singh, A. Chen, K. Hara, S. K. Choi, Sanmay Ganguly, T. Uchida, Y. Ban, N. Zwahlen, Bruce Yabsley, L. Zhao, M. Heider, M. Rozanska, D. Kotchetkov, Y. Yusa, A. Vinokurova, S. Dubey, Rahul Kumar, J. Libby, R. Louvot, Y. Chao, G. N. Taylor, R. Glattauer, V.E. Shebalin, J. Haba, W. Bartel, S. Nishida, S. Al Said, K. Hoshina, Y. Seino, Y. Onuki, K. Vervink, Z. Drásal, Marko Petrič, M. T. Prim, K. Itagaki, Z. Q. Liu, C. Bookwalter, B. G. Cheon, H. J. Hyun, S. Uozumi, P. Smerkol, Tariq Aziz, X. L. Wang, D. Heffernan, T. Morii, C. Boulahouache, J. Hasenbusch, V. Chekelian, J. Li, V. M. Aulchenko, H. Guo, T.-A. Shibata, T. Horiguchi, Y. Ono, S. Koblitz, Seema Bahinipati, Y. Choi, H. Takeichi, K. J. Nath, S. Uno, C. Schwanda, P. Krokovny, M. T. Hedges, Samo Stanič, L.M. Zhang, E. Kurihara, A.E. Bondar, P.A. Lukin, T. Nakano, K. Dutta, A. Garmash, Daniel Greenwald, M. Takizawa, B. Reisert, Y. Sakai, J. Rauch, B. K. Pal, E. L. Barberio, M. Shapkin, Noritaka Shimizu, T. Hara, L. Santelj, J. Dalseno, Robin Wedd, K. M. Williams, V. Bansal, K. Belous, A. M. Bakich, S. Korpar, Jolanta Brodzicka, John Yelton, T. Ohshima, Z. Doležal, K. Chilikin, Y. J. Kim, N. Dash, S. Iwata, H. Ozaki, H. Nakano, C. Ng, K. H. Kang, K. Cho, K. Inami, M. Sumihama, A. Heller, M. D. Peters, Motoki Iwasaki, Y. Ushiroda, N. Taniguchi, Y. M. Goh, S. H. Lee, K. Prothmann, R. Pestotnik, N. Gabyshev, D. Červenkov, A. Abdesselam, M. Steder, M. E. Sevior, I. S. Lee, D. Matvienko, Y. Miyazaki, R. Sinha, P. K. Behera, Yasushi Nagasaka, B. Kronenbitter, Sumio Yamada, E. Kato, M. Leitgab, Tao Luo, K. Tanida, F. Tenchini, T. Sumiyoshi, A. Bala, D. Epifanov, Soumya D. Mohanty, C. Pulvermacher, Martin Ritter, Dmytro Levit, Z. Natkaniec, S. L. Blyth, T. Sanuki, Shigeki Hirose, K. K. Joo, Hirokazu Miyake, R. Seidl, Y. Guan, E. Solovieva, Norihito Muramatsu, M. Huschle, K. Sakai, Y. Watanabe, S. K. Kim, A.L. Sibidanov, H. Kichimi, M. C. Chang, K. S. Park, V. Bhardwaj, T. K. Pedlar, T. Tsuboyama, H. Palka, L. E. Piilonen, G. Pakhlova, J. Wiechczynski, R. Kulasiri, S. U. Kataoka, S. Yashchenko, A. Moll, S. L. Olsen, D. Joffe, T. Julius, Po-Hsun Chen, R. Chistov, A. Vossen, O. Seon, Frank Simon, D. Semmler, Y. Unno, K. F. Chen, R. Ayad, T. Nozaki, S. Uehara, M. N. Wagner, Peter Kvasnicka, A. B. Kaliyar, Sunmin Ryu, C. W. Park, E. Won, C. Oswald, H. Atmacan, P. Vanhoefer, E. Panzenböck, B. Golob, M. Schram, N. K. Nisar, H. K. Moon, J. S. Lange, M. Ziegler, K. Adamczyk, Y. Soloviev, W. S. Hou, K. Arinstein, Y. Mikami, Alexei Kuzmin, V. Vorobyev, Nagao Kobayashi, Y. F. Liu, C. Kleinwort, Z. P. Zhang, H. Sahoo, Tara Nanut, T. Uglov, Yoji Hasegawa, S. Y. Suzuki, Richard T. Kouzes, K. Sumisawa, D. M. Asner, S. Himori, Kevin Varvell, A. Matyja, Jason Crnkovic, T. Mori, H. Aihara, Y. Usov, Jyoti Prakash Biswal, C. Liu, H. Nakazawa, A. J. Schwartz, H. Farhat, J. B. Kim, T. Higuchi, S. Ogawa, V. Gaur, Y. S. Sohn, Ferdinando Giordano, M. Nakao, E. Waheed, S. McOnie, J. MacNaughton, and P. Kapusta

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, 010308 nuclear & particles physics, Maximum likelihood, Electron–positron annihilation, 01 natural sciences, law.invention, Nuclear physics, KEKB, law, 0103 physical sciences, Radiative transfer, Michel parameters, Statistical analysis, 010306 general physics, Collider, Lepton
Abstract

We present the first measurement of the Michel parameters η ‾ and ξκ in the radiative leptonic decay of the τ lepton using 703 fb-1 of data collected with the Belle detector at the KEKB e + e − collider. The Michel parameters are measured by an unbinned maximum likelihood fit to the kinematic information of e + e − → τ + τ − → ( π + π 0 ν ‾ ) ( l − ν ν ‾ γ ) ( l = e or μ ) . The preliminary values of the measured Michel parameters are η ‾ = − 2.0 ± 1.5 ± 0.8 and ξ κ = 0.6 ± 0.4 ± 0.2 , where the first error is statistical and the second is systematic.

Published
2017

2. Induced Charge Profile in a Glass RPC Operated in Avalanche Mode

Author

K. Neichi, Y. Hoshi, S. Narita, and Akira Yamaguchi

Subjects
Avalanche mode, Physics, Nuclear and High Energy Physics, Physics::Instrumentation and Detectors, business.industry, Electrical engineering, Readout electronics, Resistive plate chamber, Charge (physics), Electrostatic induction, Signal, Nuclear Energy and Engineering, Nuclear electronics, Electrode, Optoelectronics, Electrical and Electronic Engineering, business
Abstract

We measured spatial distribution of induced charge on the thin readout wires on RPC operated in avalanche mode with the gas mixture containing SF6, C4H10, and C2H2F4. We found that the induced charge spread on the wires was ~6 mm. According to the time properties of the induced charge, there was a delayed component of the signal and they supposed to be due to propagation of induced charge on a wire to adjacent one. Considering the effect, the intrinsic charge spread by an avalanche was found to be ~2 mm.

Published
2013

3. Effects of high-energy proton and electron irradiation on GaN Schottky diode

Author

Jirohta Kasagi, S. Narita, K. Neichi, M. Itoh, Yasuhiro Sakemi, Hidetomo Yoshida, Eiichi Yamaguchi, and Toshimi Hitora

Subjects
Physics, Nuclear and High Energy Physics, Proton, Electron beam processing, Schottky diode, Breakdown voltage, Electron, Atomic physics, Instrumentation, Fluence, Diode, Dark current
Abstract

We performed high-energy proton and electron irradiation on a GaN Schottky diode and investigated the effects on its electrical properties. No significant changes in the dark current or breakdown voltage of the diode were observed for fluences up to ∼ 10 14 protons / cm 2 . The currents increased by a factor of ∼ 10 3 at a fluence of ∼ 10 15 protons / cm 2 . The currents also fluctuated unstably at these fluences but this unstable behavior was not observed after a few months. Intrinsic defects may have been induced by particle irradiation and some of them annealed through a relaxation process. Under electron irradiation, the dark currents did not show a notable increase even with the fluence of ∼ 10 16 electrons / cm 2 .

Published
2013

4. Development of the application for fitting functions using expression parsing

Author

K. Neichi

Subjects
Theoretical computer science, Parsing, Java, Computer science, computer.software_genre, Expression (mathematics), Development (topology), Simple (abstract algebra), Histogram, Algorithm design, computer, Algorithm, Computer Science::Databases, computer.programming_language
Abstract

To develop an application for fitting functions to data for analysts who do not have programming experience, we apply an expression parsing algorithm to evaluate functions and derivatives. Using the algorithm, arbitrary mathematical expressions for fitting functions are available as inputs. Therefore, we can provide simple interfaces to perform fitting functions easily, and can evaluate the derivatives of arbitrary functions analytically. This application is implemented using Java. We also report the performance of the proposed application.

Published
2016

5. Measurements of Induced Charge Profile in RPC With Submilli-Strips

Author

Y. Kikuchi, M Shoji, K. Neichi, Y. Hoshi, Akira Yamaguchi, S. Narita, and D. Miura

Subjects
Physics, Nuclear and High Energy Physics, Argon, Physics::Instrumentation and Detectors, business.industry, Readout electronics, chemistry.chemical_element, Cosmic ray, Charge (physics), STRIPS, Electrostatic induction, Tracking (particle physics), law.invention, Optics, Nuclear Energy and Engineering, chemistry, law, Scintillation counter, Electrical and Electronic Engineering, business
Abstract

It is necessary to understand the spread and spatial distribution of charge induced on readout strips or pad in RPC to utilize it for a tracking/imaging device. We have measured the profile of induced charge on submilli-size strips for cosmic ray events. The spatial spread of the charge was measured to be about 10 mm in the configuration of our study. The result was verified measuring the lateral size of the streamer using the associated optical images.

Published
2010

6. Performance of Glass RPC in Streamer Mode for Irradiation With Coherent Photons

Author

K. Neichi, Y. Hoshi, N. Saito, S. Narita, and Akira Yamaguchi

Subjects
Physics, Nuclear and High Energy Physics, Photon, business.industry, Laser, Two-photon absorption, law.invention, Optics, Nuclear Energy and Engineering, law, Ionization, Optoelectronics, Irradiation, Electrical and Electronic Engineering, business, Laser light
Abstract

We have tested the RPC operated in streamer mode irradiating the laser light, and investigated its properties. We found that the gas in the RPC can be ionized in two photon absorption process. The laser irradiation method is useful technique to investigate the characteristics of RPC systematically.

Published
2007

7. Performance of the endcap RPC in the Belle detector under high luminosity operation of the KEKB accelerator

Author

Akira Yamaguchi, T. Nagamine, K. Neichi, Y. Hoshi, and N. Kikuchi

Subjects
Physics, Nuclear physics, Nuclear and High Energy Physics, KEKB, Luminosity (scattering theory), business.industry, Detector, Background data, Electrical engineering, business, Atomic and Molecular Physics, and Optics, B-factory
Abstract

The endcap RPCs in the Belle detector at KEK B factory have operated stably with high detection efficiency since the start of the experiment, June 1999. In contrast with high luminosity operation of the KEKB accelerator, however, efficiency reduction due to high background rate has been observed in the outermost RPC layers in the endcap part of the KLM detector. To identify the background source, the background data is compared with simulation result using Geant4 simulation toolkit. Further, for higher luminosity operation of the accelerator, simulation result on the shield design for reducing the background rate is also reported.

Published
2006

8. Quenching properties of gas mixture in glass RPC operated with streamer mode

Author

M. Kumagai, K. Neichi, Kazuo Abe, Y. Hoshi, Takahashi Tatsuto, Akira Yamaguchi, and H. Yuta

Subjects
Physics, Quenching, Optical image, Nuclear and High Energy Physics, Brightness, Physics::Instrumentation and Detectors, business.industry, High Energy Physics::Lattice, Analytical chemistry, Electrostatic induction, Signal, Optics, Pulse waveform, Electron affinity, Oscilloscope, business, Instrumentation
Abstract

Quenching properties of gas mixture in a resistive plate chamber operated with streamer mode were investigated using optical image taken by the CCD camera and signal pulse waveform recorded by the digital oscilloscope. We have tested four quenching gases: C 2 H 2 F 4 , C 2 F 6 , CBrF 3 and SF 6 . Streamer size, brightness and induced charge linearly depend on the ratio of Ar to quenching gas and their slopes are a function of electron affinity for each quenching gas.

Published
2004

9. Optical study of the features of the streamer images in RPC

Author

Y. Hoshi, K. Kumagai, Akira Yamaguchi, K. Onodera, T. Takahashi, K. Neichi, H. Yuta, N. Takahashi, T. Nagamine, and Kazuo Abe

Subjects
Physics, Optical image, Quenching, Nuclear and High Energy Physics, Optics, Ccd camera, business.industry, Electrode, Resistive plate chamber, Halo, business, Instrumentation
Abstract

Optical images of the streamer from a Resistive Plate Chamber (RPC) are observed using a transparent high-voltage electrode in the operation of streamer mode. The optical images are measured using CCD camera system in mixture Ar/C4H10 with and without C2H2F4. Area of typical streamer image is approximately 12 mm 2 in both gas mixtures with its surrounding halo of 2– 4 mm in diameter. We also observed the quenching effect of C4H10 and C2H2F4 on the optical image in the chamber.

Published
2003

10. Observation of B→DKK decays

Author

A. Drutskoy, K. Abe, N. Abe, R. Abe, T. Abe, I. Adachi, Byoung Sup Ahn, H. Aihara, M. Akatsu, Y. Asano, T. Aso, V. Aulchenko, T. Aushev, A.M. Bakich, Y. Ban, E. Banas, A. Bay, I. Bedny, P.K. Behera, I. Bizjak, A. Bondar, A. Bozek, T.E. Browder, B.C.K. Casey, M.-C. Chang, P. Chang, Y. Chao, K.-F. Chen, B.G. Cheon, R. Chistov, S.-K. Choi, Y. Choi, Y.K. Choi, M. Danilov, L.Y. Dong, S. Eidelman, V. Eiges, Y. Enari, C.W. Everton, F. Fang, C. Fukunaga, N. Gabyshev, A. Garmash, T. Gershon, R. Guo, J. Haba, T. Hara, Y. Harada, H. Hayashii, M. Hazumi, E.M. Heenan, I. Higuchi, T. Higuchi, L. Hinz, T. Hokuue, Y. Hoshi, W.-S. Hou, S.-C. Hsu, H.-C. Huang, T. Igaki, Y. Igarashi, T. Iijima, K. Inami, A. Ishikawa, H. Ishino, R. Itoh, H. Iwasaki, Y. Iwasaki, H.K. Jang, J.H. Kang, J.S. Kang, P. Kapusta, S.U. Kataoka, N. Katayama, H. Kawai, Y. Kawakami, T. Kawasaki, H. Kichimi, D.W. Kim, Heejong Kim, H.J. Kim, Hyunwoo Kim, T.H. Kim, K. Kinoshita, S. Korpar, P. Križan, P. Krokovny, R. Kulasiri, S. Kumar, A. Kuzmin, Y.-J. Kwon, G. Leder, S.H. Lee, J. Li, D. Liventsev, R.-S. Lu, J. MacNaughton, G. Majumder, F. Mandl, D. Marlow, T. Matsuishi, S. Matsumoto, T. Matsumoto, W. Mitaroff, Y. Miyabayashi, H. Miyake, H. Miyata, G.R. Moloney, T. Mori, T. Nagamine, Y. Nagasaka, T. Nakadaira, E. Nakano, M. Nakao, J.W. Nam, Z. Natkaniec, K. Neichi, S. Nishida, O. Nitoh, S. Noguchi, T. Nozaki, S. Ogawa, F. Ohno, T. Ohshima, T. Okabe, S. Okuno, S.L. Olsen, Y. Onuki, W. Ostrowicz, H. Ozaki, P. Pakhlov, H. Palka, C.W. Park, H. Park, L.S. Peak, J.-P. Perroud, M. Peters, L.E. Piilonen, N. Root, M. Rozanska, K. Rybicki, H. Sagawa, S. Saitoh, Y. Sakai, H. Sakamoto, M. Satapathy, A. Satpathy, O. Schneider, S. Schrenk, S. Semenov, K. Senyo, R. Seuster, M.E. Sevior, H. Shibuya, V. Sidorov, J.B. Singh, N. Soni, S. Stanič, M. Starič, A. Sugi, A. Sugiyama, K. Sumisawa, T. Sumiyoshi, S.Y. Suzuki, T. Takahashi, F. Takasaki, K. Tamai, N. Tamura, J. Tanaka, M. Tanaka, G.N. Taylor, Y. Teramoto, S. Tokuda, M. Tomoto, T. Tomura, S.N. Tovey, K. Trabelsi, T. Tsuboyama, T. Tsukamoto, S. Uehara, K. Ueno, Y. Unno, S. Uno, Y. Ushiroda, G. Varner, K.E. Varvell, C.C. Wang, C.H. Wang, J.G. Wang, M.-Z. Wang, Y. Watanabe, E. Won, B.D. Yabsley, Y. Yamada, A. Yamaguchi, Y. Yamashita, M. Yamauchi, H. Yanai, P. Yeh, Y. Yusa, J. Zhang, Z.P. Zhang, V. Zhilich, and D. Žontar

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, KEKB, law, Invariant mass, Polarization (waves), Collider, law.invention
Abstract

The B -> D^{(*)} K^- K^{(*)0} decays have been observed for the first time. The branching fractions of the B -> D^{(*)} K^- K^{(*)0} decay modes are measured. Significant signals are found for the B -> D^{(*)} K^- K^{*0} and B^- -> D^0 K^- K^0_S decay modes. The invariant mass and polarization distributions for the K^-K^{*0} and K^-K^0_S subsystems have been studied. For the K^-K^{*0} sybsystem these distributions agree well with those expected for two-body B -> D^{(*)} a_1^-(1260) decays, with a_1^-(1260) -> K^- K^{*0}. The analysis was done using 29.4 fb^{-1} of data collected with the Belle detector at the e^+ e^- asymmetric collider KEKB.

Published
2002

11. Study of B→ρπ decays at Belle

Author

A. Gordon, Y. Chao, K. Abe, N. Abe, R. Abe, T. Abe, Byoung Sup Ahn, H. Aihara, M. Akatsu, Y. Asano, T. Aso, V. Aulchenko, T. Aushev, A.M. Bakich, Y. Ban, A. Bay, I. Bedny, P.K. Behera, I. Bizjak, A. Bondar, A. Bozek, M. Bračko, T.E. Browder, B.C.K. Casey, M.-C. Chang, P. Chang, B.G. Cheon, R. Chistov, Y. Choi, Y.K. Choi, M. Danilov, L.Y. Dong, J. Dragic, A. Drutskoy, S. Eidelman, V. Eiges, Y. Enari, C.W. Everton, F. Fang, H. Fujii, C. Fukunaga, N. Gabyshev, A. Garmash, T. Gershon, B. Golob, R. Guo, J. Haba, T. Hara, Y. Harada, N.C. Hastings, H. Hayashii, M. Hazumi, E.M. Heenan, I. Higuchi, T. Higuchi, L. Hinz, T. Hokuue, Y. Hoshi, S.R. Hou, W.-S. Hou, S.-C. Hsu, H.-C. Huang, T. Igaki, Y. Igarashi, T. Iijima, K. Inami, A. Ishikawa, H. Ishino, R. Itoh, H. Iwasaki, Y. Iwasaki, H.K. Jang, J.H. Kang, J.S. Kang, N. Katayama, Y. Kawakami, N. Kawamura, T. Kawasaki, H. Kichimi, D.W. Kim, Heejong Kim, H.J. Kim, H.O. Kim, Hyunwoo Kim, S.K. Kim, T.H. Kim, K. Kinoshita, S. Korpar, P. Krokovny, R. Kulasiri, S. Kumar, A. Kuzmin, Y.-J. Kwon, J.S. Lange, G. Leder, S.H. Lee, J. Li, A. Limosani, D. Liventsev, R.-S. Lu, J. MacNaughton, G. Majumder, F. Mandl, D. Marlow, S. Matsumoto, T. Matsumoto, W. Mitaroff, K. Miyabayashi, Y. Miyabayashi, H. Miyake, H. Miyata, G.R. Moloney, T. Mori, T. Nagamine, Y. Nagasaka, T. Nakadaira, E. Nakano, M. Nakao, J.W. Nam, Z. Natkaniec, K. Neichi, S. Nishida, O. Nitoh, S. Noguchi, T. Nozaki, S. Ogawa, T. Ohshima, T. Okabe, S. Okuno, S.L. Olsen, Y. Onuki, W. Ostrowicz, H. Ozaki, P. Pakhlov, H. Palka, C.W. Park, H. Park, L.S. Peak, J.-P. Perroud, M. Peters, L.E. Piilonen, J.L. Rodriguez, F.J. Ronga, N. Root, M. Rozanska, K. Rybicki, H. Sagawa, S. Saitoh, Y. Sakai, M. Satapathy, A. Satpathy, O. Schneider, S. Schrenk, C. Schwanda, S. Semenov, K. Senyo, R. Seuster, M.E. Sevior, H. Shibuya, V. Sidorov, J.B. Singh, S. Stanič, M. Starič, A. Sugi, A. Sugiyama, K. Sumisawa, T. Sumiyoshi, K. Suzuki, S. Suzuki, S.Y. Suzuki, T. Takahashi, F. Takasaki, K. Tamai, N. Tamura, J. Tanaka, M. Tanaka, G.N. Taylor, Y. Teramoto, S. Tokuda, S.N. Tovey, T. Tsuboyama, T. Tsukamoto, S. Uehara, K. Ueno, Y. Unno, S. Uno, Y. Ushiroda, G. Varner, K.E. Varvell, C.C. Wang, C.H. Wang, J.G. Wang, M.-Z. Wang, Y. Watanabe, E. Won, B.D. Yabsley, Y. Yamada, A. Yamaguchi, Y. Yamashita, M. Yamauchi, H. Yanai, P. Yeh, Y. Yuan, Y. Yusa, J. Zhang, Z.P. Zhang, Y. Zheng, and D. Žontar

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, KEKB, Pi, B meson
Abstract

This paper describes a study of B meson decays to the pseudoscalar-vector final state \rho\pi using 31.9\times 10^6 B\bar{B} events collected with the Belle detector at KEKB. The branching fractions B(B^+ \to \rho^0\pi^+) = (8.0^{+2.3+0.7}_{-2.0-0.7}) \times 10^{-6} and B(B^0 -> \rho^{+-} \pi^{-+}) = (20.8^{+6.0+2.8}_{-6.3-3.1}) \times 10^{-6} are obtained. In addition, a 90% confidence level upper limit of B(B^0 \to \rho^0\pi^0) < 5.3 \times 10^{-6}is reported.

Published
2002

12. Measurement of χ2 production in two-photon collisions

Author

K. Abe, R. Abe, T. Abe, I. Adachi, Byoung Sup Ahn, H. Aihara, M. Akatsu, Y. Asano, T. Aso, V. Aulchenko, T. Aushev, A.M. Bakich, Y. Ban, E. Banas, A. Bay, P.K. Behera, A. Bondar, A. Bozek, M. Bračko, J. Brodzicka, B.C.K. Casey, P. Chang, Y. Chao, B.G. Cheon, R. Chistov, S.-K. Choi, Y. Choi, M. Danilov, L.Y. Dong, A. Drutskoy, S. Eidelman, V. Eiges, Y. Enari, C. Fukunaga, N. Gabyshev, A. Garmash, T. Gershon, R. Guo, F. Handa, T. Hara, Y. Harada, H. Hayashii, M. Hazumi, E.M. Heenan, I. Higuchi, T. Hojo, T. Hokuue, Y. Hoshi, K. Hoshina, S.R. Hou, W.-S. Hou, H.-C. Huang, T. Igaki, Y. Igarashi, K. Inami, A. Ishikawa, R. Itoh, M. Iwamoto, H. Iwasaki, Y. Iwasaki, H.K. Jang, J. Kaneko, J.H. Kang, J.S. Kang, P. Kapusta, S.U. Kataoka, N. Katayama, H. Kawai, Y. Kawakami, N. Kawamura, T. Kawasaki, H. Kichimi, D.W. Kim, Heejong Kim, H.J. Kim, H.O. Kim, Hyunwoo Kim, S.K. Kim, T.H. Kim, P. Krokovny, R. Kulasiri, S. Kumar, A. Kuzmin, Y.-J. Kwon, G. Leder, S.H. Lee, J. Li, D. Liventsev, R.-S. Lu, J. MacNaughton, G. Majumder, F. Mandl, S. Matsumoto, T. Matsumoto, K. Miyabayashi, H. Miyake, H. Miyata, G.R. Moloney, T. Mori, T. Nagamine, Y. Nagasaka, E. Nakano, M. Nakao, J.W. Nam, Z. Natkaniec, K. Neichi, S. Nishida, O. Nitoh, S. Noguchi, T. Nozaki, S. Ogawa, F. Ohno, T. Ohshima, T. Okabe, S. Okuno, S.L. Olsen, Y. Onuki, W. Ostrowicz, H. Ozaki, P. Pakhlov, H. Palka, C.W. Park, H. Park, K.S. Park, L.S. Peak, J.-P. Perroud, M. Peters, L.E. Piilonen, N. Root, K. Rybicki, H. Sagawa, S. Saitoh, Y. Sakai, M. Satapathy, O. Schneider, S. Schrenk, C. Schwanda, S. Semenov, K. Senyo, R. Seuster, M.E. Sevior, H. Shibuya, B. Shwartz, V. Sidorov, J.B. Singh, S. Stanič, M. Starič, A. Sugiyama, K. Sumisawa, T. Sumiyoshi, S. Suzuki, S.K. Swain, T. Takahashi, F. Takasaki, K. Tamai, N. Tamura, M. Tanaka, G.N. Taylor, Y. Teramoto, S. Tokuda, T. Tomura, S.N. Tovey, T. Tsuboyama, T. Tsukamoto, S. Uehara, K. Ueno, S. Uno, S.E. Vahsen, G. Varner, K.E. Varvell, C.C. Wang, C.H. Wang, J.G. Wang, M.-Z. Wang, Y. Watanabe, E. Won, B.D. Yabsley, Y. Yamada, A. Yamaguchi, Y. Yamashita, M. Yamauchi, H. Yanai, J. Yashima, Y. Yuan, Y. Yusa, J. Zhang, Z.P. Zhang, V. Zhilich, and D. Žontar

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, KEKB, Branching fraction, Product (mathematics), High Energy Physics::Experiment, Production (computer science), High Energy Physics - Experiment
Abstract

The production of the \chi_{c2} charmonium state in two-photon collisions has been measured with the Belle detector at the KEKB e^+e^- collider. A clear signal for \chi_{c2} --> \gamma J/\psi, J/\psi --> l^+l^- is observed in a 32.6fb^{-1} data sample accumulated at center-of-mass energies near 10.6GeV, and the product of its two-photon decay width and branching fraction is determined to be \Gamma_{\gamma\gamma}(\chi_{c2})B(\chi_{c2} --> \gamma J/\psi) B(J/\psi --> l^+l^-)= 13.5 +/- 1.3(stat.) +/- 1.1(syst.)eV., Comment: 16 pages, 5 figures, to be submitted to Phys. Lett. B

Published
2002

13. Measurement of (→Dℓ) and determination of |V

Author

Hiroyuki Sagawa, G. Leder, D. W. Kim, Y. Watanabe, H. Kichimi, K. Tamai, M. E. Sevior, T. Tsuboyama, Masashi Hazumi, Shaji Kumar, J. L. Rodriguez, H. Miyake, M. Yamauchi, A. Murakami, Y. Zheng, S. Matsumoto, M. Satapathy, N. Kawamura, R. Abe, M. Rozanska, H. Palka, L. E. Piilonen, K. S. Park, L. S. Peak, Y. Ushiroda, R. Guo, S. Uehara, Shih-Chieh Hsu, M. Tanaka, I. Higuchi, J. Haba, J. W. Nam, S. Behari, S. Yanaka, A. Garmash, Hirokazu Ishino, T. Iijima, D. J. Jackson, S. Noguchi, Byoung Sup Ahn, D. Liventsev, H. K. Jang, R. Kulasiri, T. Aushev, T. Hojo, T. Nakadaira, N. Katayama, I. Adachi, S. Y. Suzuki, H. J. Kim, J. P. Perroud, Y. Sakai, S. R. Hou, H. Kawai, B. C. K. Casey, Yasushi Nagasaka, E.J. Prebys, S. N. Tovey, S. K. Swain, J. Zhang, R. Itoh, R. Chistov, F. Fang, K. Sumisawa, Kevin Varvell, D. Žontar, A. Bondar, S. Korpar, V.N. Zhilich, M. Takita, Masashi Yokoyama, Y. Ban, Tsukasa Aso, Ascelin Gordon, H. Aihara, E. M. Heenan, Y. Chao, B. Shwartz, Y. Iwasaki, Chikara Fukunaga, J. B. Singh, Y. Tanaka, S. K. Choi, A. Kuzmin, S. Semenov, Y. J. Kwon, Y. Igarashi, Hiroshi Sakamoto, K. Miyabayashi, S. Ogawa, Ho Kim, Kyo Yoshida, Hirokazu Ikeda, J. G. Wang, Takahiko Matsubara, T. Sumiyoshi, S. E. Vahsen, T. Tomura, L. Y. Dong, C. W. Park, E. Won, N. Tamura, T. J. Gershon, T. Hokuue, S. K. Kim, J. Yashima, K. Senyo, K. Ueno, T. Kawasaki, S. Stanič, Makoto Tomoto, N.I. Root, Heejong Kim, Kazunori Hanagaki, K. Neichi, Y. Mikami, Hitoshi Yamamoto, M. Nakao, K. Trabelsi, J. S. Kang, P. Chang, T. Takahashi, V. M. Aulchenko, H. Fujii, O. Nitoh, J. Tanaka, Masaki Fukushima, Shigeki Mori, Kazuo Abe, H. Ozaki, Y. Asano, P. Kapusta, S. Okuno, Y. Yusa, J. MacNaughton, W. S. Hou, F. Handa, M. D. Peters, T. Abe, Y. Choi, M. Yamaga, Takuya Higuchi, T. Hara, S. H. Lee, A. Ishikawa, Y. Teramoto, A. M. Bakich, Bruce Yabsley, Elzbieta Banas, T. Okabe, N. C. Hastings, Y. Yamashita, F. Takasaki, Z. Natkaniec, T. Ohshima, H. Konishi, T. Nagamine, S. Nishida, H. C. Huang, P. Križan, T. Nozaki, S. Schrenk, W. Ostrowicz, E. Nakano, C. H. Wang, N. Gabyshev, You-Jin Yuan, A. Yamaguchi, Hyunwoo Kim, C. C. Zhang, H. Shibuya, V. Eiges, Rong-Shyang Lu, J. H. Kang, J. Ryuko, T. E. Browder, Hiroyuki Iwasaki, T. Tsukamoto, A. Sugiyama, C.W. Everton, Byung Gu Cheon, K. Hara, K. Hoshina, T. Mori, S. Uno, S. Eidelman, P. Pakhlov, A. Satpathy, S. L. Olsen, H. Park, A. Bozek, T. Matsumoto, M. Z. Wang, K. Kinoshita, A. Drutskoy, P. Krokovny, Y. Nagashima, G. N. Taylor, J. S. Lange, H. Hayashii, K. Inami, Changwon Park, G. R. Moloney, Y. Unno, P. Jalocha, H. W. Zhao, H. Hamasaki, Yasuhiko Yamada, H. Miyata, Prafulla Kumar Behera, Y. Hoshi, T.H. Kim, C. C. Wang, and M. Akatsu

Subjects
Physics, Nuclear and High Energy Physics, Muon, KEKB, Branching fraction, Cabibbo–Kobayashi–Maskawa matrix, Electron–positron annihilation, Analytical chemistry, Form factor (quantum field theory), Resonance, Electron, Atomic physics
Abstract

We present a measurement of the branching fraction for the semileptonic B decay B 0 →D + l − ν , where l− can be either an electron or a muon. We find Γ( B 0 →D + l − ν )=(13.79±0.76±2.51) ns −1 , and the resulting branching fraction B ( B 0 →D + l − ν )=(2.13±0.12±0.39)% , where the first error is statistical and the second systematic. We also investigate the B 0 →D + l − ν form factor and the implications of the result for |Vcb|. From a fit to the differential decay distribution we obtain the rate normalization |Vcb|FD(1)=(4.11±0.44±0.52)×10−2. Using a theoretical calculation of FD(1), the Cabibbo–Kobayashi–Maskawa matrix element |Vcb|=(4.19±0.45±0.53±0.30)×10−2 is obtained, where the last error comes from the theoretical uncertainty of FD(1). The results are based on a data sample of 10.2fb−1 recorded at the ϒ(4S) resonance with the Belle detector at the KEKB e+e− collider.

Published
2002

14. The Belle detector

Author

A. Abashian, K. Gotow, N. Morgan, L. Piilonen, S. Schrenk, K. Abe, I. Adachi, J.P. Alexander, K. Aoki, S. Behari, Y. Doi, R. Enomoto, H. Fujii, Y. Fujita, Y. Funahashi, J. Haba, H. Hamasaki, T. Haruyama, K. Hayashi, Y. Higashi, N. Hitomi, S. Igarashi, Y. Igarashi, T. Iijima, Hirokazu Ikeda, Hitomi Ikeda, R. Itoh, M. Iwai, H. Iwasaki, Y. Iwasaki, K.K. Joo, K. Kasami, N. Katayama, M. Kawai, H. Kichimi, T. Kobayashi, S. Koike, Y. Kondo, M.H. Lee, Y. Makida, A. Manabe, T. Matsuda, T. Murakami, S. Nagayama, M. Nakao, T. Nozaki, K. Ogawa, R. Ohkubo, Y. Ohnishi, H. Ozaki, H. Sagawa, M. Saito, Y. Sakai, T. Sasaki, N. Sato, T. Sumiyoshi, J. Suzuki, J.I. Suzuki, S. Suzuki, F. Takasaki, K. Tamai, M. Tanaka, T. Tatomi, T. Tsuboyama, K. Tsukada, T. Tsukamoto, S. Uehara, N. Ujiie, S. Uno, B. Yabsley, Y. Yamada, H. Yamaguchi, H. Yamaoka, Y. Yamaoka, M. Yamauchi, Y. Yoshimura, H. Zhao, R. Abe, G. Iwai, T. Kawasaki, H. Miyata, K. Shimada, S. Takahashi, N. Tamura, H. Hanada, T. Nagamine, M. Nakajima, T. Nakajima, S. Narita, M. Sanpei, T. Takayama, M. Ueki, M. Yamaga, A. Yamaguchi, B.S. Ahn, J.S. Kang, Hyunwoo Kim, C.W. Park, H. Park, H.S. Ahn, H.K. Jang, C.H. Kim, S.K. Kim, S.H. Lee, C.S. Park, E. Won, H. Aihara, T. Higuchi, H. Kawai, T. Matsubara, T. Nakadaira, H. Tajima, J. Tanaka, T. Tomura, M. Yokoyama, M. Akatsu, K. Fujimoto, M. Hirose, K. Inami, A. Ishikawa, S. Itami, T. Kani, T. Matsumoto, I. Nagai, T. Okabe, T. Oshima, K. Senyo, A. Sugi, A. Sugiyama, S. Suitoh, M. Tomoto, K. Yoshida, R. Akhmetshin, P. Chang, Y. Chao, Y.Q. Chen, W.S. Hou, S.C. Hsu, H.C. Huang, T.J. Huang, M.C. Lee, R.S. Lu, J.C. Peng, K.C. Peng, S. Sahu, H.F. Sung, K.L. Tsai, K. Ueno, C.C. Wang, M.Z. Wang, G. Alimonti, T.E. Browder, B.C.K. Casey, F. Fang, H. Guler, M. Jones, Y. Li, S.L. Olsen, M. Peters, J.L. Rodriguez, M. Rosen, S. Swain, K. Trabelsi, G. Varner, H. Yamamoto, Y.H. Zheng, Q. An, H.F. Chen, Y.F. Wang, Z.Z. Xu, S.W. Ye, Z.P. Zhang, M. Asai, Y. Asano, S. Mori, S. Stanič, Y. Tsujita, J. Zhang, D. Žontar, T. Aso, V. Aulchenko, D. Beiline, A. Bondar, L. Dneprovsky, S. Eidelman, A. Garmash, A. Kuzmin, L. Romanov, N. Root, B. Shwartz, A. Sidorov, V. Sidorov, Y. Usov, V. Zhilich, A.M. Bakich, L.S. Peak, K.E. Varvell, E. Banas, A. Bozek, P. Jalocha, P. Kapusta, Z. Natkaniec, W. Ostrowicz, H. Palka, M. Rozanka, K. Rybicki, P.K. Behera, A. Mohapatra, M. Satapathy, Y.H. Chang, H.S. Chen, L.Y. Dong, J. Li, H.M. Liu, Z.P. Mao, C.X. Yu, C.C. Zhang, S.Q. Zhang, Z.G. Zhao, Z.P. Zheng, B.G. Cheon, Y. Choi, D.W. Kim, J.W. Nam, S. Chidzik, K. Korotuschenko, C. Leonidopoulos, T. Liu, D. Marlow, C. Mindas, E. Prebys, R. Rabberman, W. Sands, R. Wixted, S. Choi, J. Dragic, C.W. Everton, A. Gordon, N.C. Hastings, E.M. Heenan, L.C. Moffitt, G.R. Moloney, G.F. Moorhead, M.E. Sevior, G.N. Taylor, S.N. Tovey, A. Drutskoy, R. Kagan, P. Pakhlov, S. Semenov, C. Fukunaga, R. Suda, M. Fukushima, V.I. Goriletsky, B.V. Grinyov, V.R. Lyubinsky, A.I. Panova, K.V. Shakhova, L.I. Shpilinskaya, E.L. Vinograd, B.G. Zaslavsky, R.S. Guo, F. Haitani, Y. Hoshi, K. Neichi, K. Hara, T. Hara, M. Hazumi, T. Hojo, D. Jackson, H. Miyake, Y. Nagashima, J. Ryuko, K. Sumisawa, M. Takita, T. Yamanaka, H. Hayashii, K. Miyabayashi, S. Noguchi, S. Hikita, H. Hirano, K. Hoshina, H. Mamada, O. Nitoh, N. Okazaki, T. Yokoyama, H. Ishino, S. Ichizawa, T. Hirai, H. Kakuno, J. Kaneko, T. Nakamura, Y. Ohshima, Y. Watanabe, S. Yanaka, Y. Inoue, E. Nakano, T. Takahashi, Y. Teramoto, J.H. Kang, H.J. Kim, Heejong Kim, Y.-J. Kwon, E. Kurihara, T. Ooba, K. Suzuki, Y. Unno, N. Kawamura, H. Yuta, K. Kinoshita, A. Satpathy, S. Kobayashi, T. Kuniya, A. Murakami, S. Kumar, J. Singh, J. Lange, R. Stock, S. Matsumoto, M. Watanabe, H. Matsuo, S. Nishida, T. Nomura, H. Sakamoto, N. Sasao, Y. Ushiroda, Y. Nagasaka, Y. Tanaka, S. Ogawa, H. Shibuya, K. Hanagaki, S. Okuno, D.Z. Shen, D.S. Yan, Z.W. Yin, N. Tan, C.H. Wang, T. Yamaki, and Y. Yamashita

Subjects
Physics, Nuclear and High Energy Physics, Spectrometer, Meson, Physics::Instrumentation and Detectors, Detector, Particle detector, Particle identification, Belle experiment, Semiconductor detector, Nuclear physics, KEKB, Computer Science::Programming Languages, Physics::Accelerator Physics, High Energy Physics::Experiment, Instrumentation
Abstract

The BELLE detector for experiments at KEKB, a high luminosity, energy asymmetric B-factory, is now being constructed at KEK. An overview of the detector systems and their status is presented.

Published
2002

15. Determination of |V| using the semileptonic decay →De

Author

K. Abe, R. Abe, T. Abe, I. Adachi, Byoung Sup Ahn, H. Aihara, M. Akatsu, Y. Asano, T. Aso, V. Aulchenko, T. Aushev, A.M. Bakich, Y. Ban, E. Banas, S. Behari, P.K. Behera, A. Bondar, A. Bozek, T.E. Browder, B.C.K. Casey, P. Chang, Y. Chao, B.G. Cheon, R. Chistov, S.-K. Choi, Y. Choi, L.Y. Dong, A. Drutskoy, S. Eidelman, V. Eiges, C.W. Everton, F. Fang, H. Fujii, C. Fukunaga, M. Fukushima, N. Gabyshev, A. Garmash, T. Gershon, A. Gordon, R. Guo, J. Haba, H. Hamasaki, K. Hanagaki, F. Handa, K. Hara, T. Hara, N.C. Hastings, H. Hayashii, M. Hazumi, E.M. Heenan, I. Higuchi, T. Higuchi, T. Hojo, T. Hokuue, Y. Hoshi, K. Hoshina, S.R. Hou, W.-S. Hou, S.-C. Hsu, H.-C. Huang, Y. Igarashi, T. Iijima, H. Ikeda, K. Inami, A. Ishikawa, H. Ishino, R. Itoh, H. Iwasaki, Y. Iwasaki, D.J. Jackson, P. Jalocha, H.K. Jang, J.H. Kang, J.S. Kang, P. Kapusta, N. Katayama, H. Kawai, N. Kawamura, T. Kawasaki, H. Kichimi, D.W. Kim, Heejong Kim, H.J. Kim, H.O. Kim, Hyunwoo Kim, S.K. Kim, T.H. Kim, K. Kinoshita, H. Konishi, S. Korpar, P. Križan, P. Krokovny, R. Kulasiri, S. Kumar, A. Kuzmin, Y.-J. Kwon, J.S. Lange, G. Leder, S.H. Lee, D. Liventsev, R.-S. Lu, J. MacNaughton, T. Matsubara, S. Matsumoto, T. Matsumoto, Y. Mikami, K. Miyabayashi, H. Miyake, H. Miyata, G.R. Moloney, S. Mori, T. Mori, A. Murakami, T. Nagamine, Y. Nagasaka, Y. Nagashima, T. Nakadaira, E. Nakano, M. Nakao, J.W. Nam, Z. Natkaniec, K. Neichi, S. Nishida, O. Nitoh, S. Noguchi, T. Nozaki, S. Ogawa, T. Ohshima, T. Okabe, S. Okuno, S.L. Olsen, W. Ostrowicz, H. Ozaki, P. Pakhlov, H. Palka, C.S. Park, C.W. Park, H. Park, K.S. Park, L.S. Peak, J.-P. Perroud, M. Peters, L.E. Piilonen, E. Prebys, J.L. Rodriguez, N. Root, M. Rozanska, J. Ryuko, H. Sagawa, Y. Sakai, H. Sakamoto, M. Satapathy, A. Satpathy, S. Schrenk, S. Semenov, K. Senyo, M.E. Sevior, H. Shibuya, B. Shwartz, J.B. Singh, S. Stanič, A. Sugiyama, K. Sumisawa, T. Sumiyoshi, S. Suzuki, S.Y. Suzuki, S.K. Swain, T. Takahashi, F. Takasaki, M. Takita, K. Tamai, N. Tamura, J. Tanaka, M. Tanaka, Y. Tanaka, G.N. Taylor, Y. Teramoto, M. Tomoto, T. Tomura, S.N. Tovey, K. Trabelsi, T. Tsuboyama, T. Tsukamoto, S. Uehara, K. Ueno, Y. Unno, S. Uno, Y. Ushiroda, S.E. Vahsen, K.E. Varvell, C.C. Wang, C.H. Wang, J.G. Wang, M.-Z. Wang, Y. Watanabe, E. Won, B.D. Yabsley, Y. Yamada, M. Yamaga, A. Yamaguchi, H. Yamamoto, Y. Yamashita, M. Yamauchi, S. Yanaka, J. Yashima, M. Yokoyama, K. Yoshida, Y. Yuan, Y. Yusa, C.C. Zhang, J. Zhang, H.W. Zhao, Y. Zheng, V. Zhilich, and D. Žontar

Subjects
Nuclear physics, Physics, Semileptonic decay, Nuclear and High Energy Physics, KEKB, Branching fraction, Electron–positron annihilation, Form factor (quantum field theory), Value (computer science), Resonance, Storage ring
Abstract

We present a measurement of the Cabibbo–Kobayashi–Maskawa (CKM) matrix element |Vcb| using a 10.2 fb−1 data sample recorded at the ϒ(4S) resonance with the Belle detector at the KEKB asymmetric e+e− storage ring. By extrapolating the differential decay width of the B 0 →D ∗+ e − ν decay to the kinematic limit at which the D ∗+ is at rest with respect to the B 0 , we extract the product of |Vcb| with the normalization of the decay form factor F(1), |Vcb|F(1)=(3.54±0.19±0.18)×10−2, where the first error is statistical and the second is systematic. A value of |Vcb|=(3.88±0.21±0.20±0.19)×10−2 is obtained using a theoretical calculation of F(1), where the third error is due to the theoretical uncertainty in the value of F(1). The branching fraction B ( B 0 →D ∗+ e − ν ) is measured to be (4.59±0.23±0.40)×10−2.

Published
2002

16. Measurement of the branching fraction for B→η′K and search for B→η′π+

Author

K Abe, R Abe, I Adachi, B.S Ahn, H Aihara, M Akatsu, Y Asano, T Aso, V Aulchenko, A.M Bakich, E Banas, S Behari, P.K Behera, D Beiline, A Bondar, A Bozek, T.E Browder, B.C.K Casey, P Chang, Y Chao, B.G Cheon, R Chistov, S.-K Choi, Y Choi, L.Y Dong, J Dragic, S Eidelman, Y Enari, F Fang, H Fujii, C Fukunaga, M Fukushima, N Gabyshev, A Garmash, T Gershon, A Gordon, K Gotow, R Guo, J Haba, H Hamasaki, K Hara, T Hara, N.C Hastings, H Hayashii, M Hazumi, E.M Heenan, I Higuchi, T Higuchi, H Hirano, T Hojo, Y Hoshi, K Hoshina, S.R Hou, W.-S Hou, S.-C Hsu, H.-C Huang, Y Igarashi, T Iijima, H Ikeda, K Inami, A Ishikawa, H Ishino, R Itoh, G Iwai, H Iwasaki, Y Iwasaki, D.J Jackson, P Jalocha, H.K Jang, J Kaneko, J.H Kang, J.S Kang, N Katayama, H Kawai, N Kawamura, T Kawasaki, H Kichimi, D.W Kim, Heejong Kim, H.J Kim, Hyunwoo Kim, S.K Kim, T.H Kim, K Kinoshita, S Kobayashi, H Konishi, P Krokovny, R Kulasiri, S Kumar, A Kuzmin, Y.-J Kwon, J.S Lange, G Leder, S.H Lee, D Liventsev, R.-S Lu, T Matsubara, S Matsumoto, T Matsumoto, J MacNaughton, Y Mikami, K Miyabayashi, H Miyake, H Miyata, G.R Moloney, S Mori, T Mori, A Murakami, T Nagamine, Y Nagasaka, Y Nagashima, T Nakadaira, E Nakano, M Nakao, J.W Nam, S Narita, Z Natkaniec, K Neichi, S Nishida, O Nitoh, S Noguchi, T Nozaki, S Ogawa, T Ohshima, T Okabe, S Okuno, H Ozaki, P Pakhlov, H Palka, C.S Park, C.W Park, H Park, L.S Peak, M Peters, L.E Piilonen, E Prebys, J.L Rodriguez, N Root, M Rozanska, K Rybicki, H Sagawa, Y Sakai, H Sakamoto, M Satapathy, A Satpathy, S Semenov, K Senyo, M.E Sevior, H Shibuya, B Shwartz, S Stanič, A Sugi, A Sugiyama, K Sumisawa, T Sumiyoshi, K Suzuki, S Suzuki, S.Y Suzuki, S.K Swain, T Takahashi, M Takita, K Tamai, N Tamura, J Tanaka, M Tanaka, Y Tanaka, Y Teramoto, M Tomoto, T Tomura, S.N Tovey, K Trabelsi, T Tsuboyama, T Tsukamoto, S Uehara, K Ueno, Y Unno, S Uno, Y Ushiroda, K.E Varvell, C.C Wang, C.H Wang, J.G Wang, M.-Z Wang, Y Watanabe, E Won, B.D Yabsley, Y Yamada, M Yamaga, A Yamaguchi, Y Yamashita, M Yamauchi, S Yanaka, J Yashima, K Yoshida, Y Yusa, H Yuta, C.C Zhang, J Zhang, H.W Zhao, Y Zheng, V Zhilich, and D Žontar

Subjects
Physics, Particle physics, Nuclear and High Energy Physics, Meson, Branching fraction, Pi, High Energy Physics::Experiment, Nuclear Experiment, Confidence interval
Abstract

We report measurements for two-body charmless B decays with an eta' meson in the final state. Using 11.1X10^6 BBbar pairs collected with the Belle detector, we find BF(B^+ ->eta'K^+)=(79^+12_-11 +-9)x10^-6 and BF(B^0 -> eta'K^0)=(55^+19_-16 +-8)x10^-6, where the first and second errors are statistical and systematic, respectively. No signal is observed in the mode B^+ -> eta' pi^+, and we set a 90% confidence level upper limit of BF(B^+-> eta'pi^+) eta'K^+- decays is investigated and a limit at 90% confidence level of -0.20

Published
2001
Full Text
View/download PDF

17. A measurement of the branching fraction for the inclusive B→Xγ decays with the Belle detector

Author

K. Abe, I. Adachi, Byoung Sup Ahn, H. Aihara, M. Akatsu, G. Alimonti, K. Aoki, K. Asai, Y. Asano, T. Aso, V. Aulchenko, T. Aushev, A.M. Bakich, E. Banas, W. Bartel, S. Behari, P.K. Behera, D. Beiline, A. Bondar, A. Bozek, T.E. Browder, B.C.K. Casey, P. Chang, Y. Chao, B.G. Cheon, S.-K. Choi, Y. Choi, Y. Doi, J. Dragic, A. Drutskoy, S. Eidelman, Y. Enari, R. Enomoto, F. Fang, H. Fujii, C. Fukunaga, M. Fukushima, A. Garmash, A. Gordon, K. Gotow, H. Guler, R. Guo, J. Haba, H. Hamasaki, K. Hanagaki, F. Handa, K. Hara, T. Hara, T. Haruyama, N.C. Hastings, K. Hayashi, H. Hayashii, M. Hazumi, E.M. Heenan, Y. Higasino, I. Higuchi, T. Higuchi, H. Hirano, T. Hojo, Y. Hoshi, W.-S. Hou, S.-C. Hsu, H.-C. Huang, S. Ichizawa, Y. Igarashi, T. Iijima, H. Ikeda, K. Ikeda, K. Inami, A. Ishikawa, H. Ishino, R. Itoh, G. Iwai, H. Iwasaki, Y. Iwasaki, D.J. Jackson, P. Jalocha, H.K. Jang, M. Jones, R. Kagan, H. Kakuno, J. Kaneko, J.H. Kang, J.S. Kang, P. Kapusta, N. Katayama, H. Kawai, N. Kawamura, T. Kawasaki, H. Kichimi, D.W. Kim, Heejong Kim, H.J. Kim, Hyunwoo Kim, S.K. Kim, K. Kinoshita, K. Korotushenko, P. Krokovny, R. Kulasiri, S. Kumar, T. Kuniya, E. Kurihara, A. Kuzmin, Y.-J. Kwon, J.S. Lange, M.H. Lee, S.H. Lee, H.B. Li, D. Liventsev, R.-S. Lu, A. Manabe, T. Matsubara, S. Matsui, S. Matsumoto, T. Matsumoto, Y. Mikami, K. Misono, K. Miyabayashi, H. Miyake, H. Miyata, L.C. Moffitt, G.R. Moloney, G.F. Moorhead, S. Mori, A. Murakami, T. Nagamine, Y. Nagasaka, Y. Nagashima, T. Nakadaira, E. Nakano, M. Nakao, J.W. Nam, S. Narita, Z. Natkaniec, K. Neichi, S. Nishida, O. Nitoh, S. Noguchi, T. Nozaki, S. Ogawa, T. Ohshima, Y. Ohshima, T. Okabe, T. Okazaki, S. Okuno, S.L. Olsen, W. Ostrowicz, H. Ozaki, H. Palka, C.S. Park, C.W. Park, H. Park, L.S. Peak, M. Peters, L.E. Piilonen, E. Prebys, J.L. Rodriguez, N. Root, M. Rozanska, K. Rybicki, J. Ryuko, H. Sagawa, Y. Sakai, H. Sakamoto, M. Satapathy, A. Satpathy, S. Schrenk, S. Semenov, K. Senyo, M.E. Sevior, H. Shibuya, B. Shwartz, V. Sidorov, J.B. Singh, S. Stanič, A. Sugi, A. Sugiyama, K. Sumisawa, T. Sumiyoshi, K. Suzuki, S. Suzuki, S.Y. Suzuki, S.K. Swain, H. Tajima, T. Takahashi, F. Takasaki, M. Takita, K. Tamai, N. Tamura, J. Tanaka, M. Tanaka, Y. Tanaka, G.N. Taylor, Y. Teramoto, M. Tomoto, T. Tomura, S.N. Tovey, K. Trabelsi, T. Tsuboyama, Y. Tsujita, T. Tsukamoto, S. Uehara, K. Ueno, N. Ujiie, Y. Unno, S. Uno, Y. Ushiroda, Y. Usov, S.E. Vahsen, G. Varner, K.E. Varvell, C.C. Wang, C.H. Wang, M.-Z. Wang, T.J. Wang, Y. Watanabe, E. Won, B.D. Yabsley, Y. Yamada, M. Yamaga, A. Yamaguchi, H. Yamamoto, H. Yamaoka, Y. Yamaoka, Y. Yamashita, M. Yamauchi, S. Yanaka, M. Yokoyama, K. Yoshida, Y. Yusa, H. Yuta, C.C. Zhang, J. Zhang, Y. Zheng, V. Zhilich, and D. Žontar

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, KEKB, Branching fraction, Detector, Radiative transfer, Resonance, B meson, Storage ring, High Energy Physics - Experiment
Abstract

We have measured the branching fraction of the inclusive radiative B meson decay B --> X(s) gamma to be Br(B->X(s)gamma)=(3.36 +/- 0.53(stat) +/- 0.42(sys) +0.50-0.54(th)) x 10^{-4}. The result is based on a sample of 6.07 x 10^6 BBbar events collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric e^+e^- storage ring., Comment: 14 pages, 6 Postsript figures, uses elsart.cls

Published
2001

18. A search for a freonless gas mixture for glass RPC

Author

F. Handa, Y. Yusa, N. Murono, Koji Abe, I. Higuchi, M. Yamaga, T. Nagamine, K. Watanabe, Y. Hoshi, K. Kumagai, Y. Mikami, Akira Yamaguchi, S. Narita, N. Kawamura, H. Yuta, N. Takahashi, and K. Neichi

Subjects
Nuclear and High Energy Physics, Resistive touchscreen, Materials science, Argon, Freon, Analytical chemistry, chemistry.chemical_element, Butane, Particle detector, Belle experiment, Sulfur hexafluoride, chemistry.chemical_compound, Nuclear Energy and Engineering, chemistry, Electrode, Electrical and Electronic Engineering
Abstract

We have operated successfully glass resistive plate counters in the streamer mode at the BELLE experiment by using a nonflammable gas mixture of argon 30%, butane-silver 8%, and freon, HFC-134a 62%. This freon is non-ozone-depleting but has a high global warming potential (1300 times higher than that of CO/sub 2/). Thus freon gases might be unusable in the near future. We tested the performance of a glass resistive plate counter operated in the streamer mode with an alternative gas mixtures of argon, butane, CO/sub 2/, and/or O/sub 2/ gases and found an efficiency of about 90%.

Published
2001

19. Measurement ofBd0−B¯d0Mixing Rate from the Time Evolution of Dilepton Events at theϒ(4S)

Author

K. Abe, I. Adachi, Byoung Sup Ahn, H. Aihara, M. Akatsu, G. Alimonti, K. Aoki, K. Asai, M. Asai, Y. Asano, T. Aso, V. Aulchenko, T. Aushev, A. M. Bakich, E. Banas, S. Behari, P. K. Behera, D. Beiline, A. Bondar, A. Bozek, T. E. Browder, B. C. K. Casey, P. Chang, Y. Chao, B. G. Cheon, S.-K. Choi, Y. Choi, Y. Doi, J. Dragic, S. Eidelman, Y. Enari, R. Enomoto, C. W. Everton, F. Fang, H. Fujii, Y. Fujita, C. Fukunaga, M. Fukushima, A. Garmash, A. Gordon, K. Gotow, H. Guler, R. Guo, J. Haba, T. Haji, H. Hamasaki, K. Hanagaki, F. Handa, K. Hara, T. Hara, N. C. Hastings, K. Hayashi, H. Hayashii, M. Hazumi, E. M. Heenan, I. Higuchi, T. Higuchi, T. Hirai, H. Hirano, T. Hojo, Y. Hoshi, W.-S. Hou, S.-C. Hsu, H.-C. Huang, Y.-C. Huang, S. Ichizawa, Y. Igarashi, T. Iijima, H. Ikeda, K. Ikeda, K. Inami, Y. Inoue, A. Ishikawa, H. Ishino, R. Itoh, G. Iwai, H. Iwasaki, Y. Iwasaki, D. J. Jackson, P. Jalocha, H. K. Jang, M. Jones, R. Kagan, H. Kakuno, J. Kaneko, J. H. Kang, J. S. Kang, P. Kapusta, K. Kasami, N. Katayama, H. Kawai, M. Kawai, N. Kawamura, T. Kawasaki, H. Kichimi, D. W. Kim, Heejong Kim, H. J. Kim, Hyunwoo Kim, S. K. Kim, K. Kinoshita, S. Kobayashi, S. Koike, S. Koishi, H. Konishi, K. Korotushenko, P. Krokovny, R. Kulasiri, S. Kumar, T. Kuniya, E. Kurihara, A. Kuzmin, Y.-J. Kwon, M. H. Lee, S. H. Lee, C. Leonidopoulos, H.-B. Li, R.-S. Lu, Y. Makida, A. Manabe, D. Marlow, T. Matsubara, T. Matsuda, S. Matsui, S. Matsumoto, T. Matsumoto, K. Miyabayashi, H. Miyake, H. Miyata, L. C. Moffitt, A. Mohapatra, G. R. Moloney, G. F. Moorhead, S. Mori, T. Mori, A. Murakami, T. Nagamine, Y. Nagasaka, Y. Nagashima, T. Nakadaira, E. Nakano, M. Nakao, H. Nakazawa, J. W. Nam, S. Narita, Z. Natkaniec, K. Neichi, S. Nishida, O. Nitoh, S. Noguchi, T. Nozaki, S. Ogawa, T. Ohshima, Y. Ohshima, T. Okabe, T. Okazaki, S. Okuno, S. L. Olsen, H. Ozaki, P. Pakhlov, H. Palka, C. S. Park, C. W. Park, H. Park, L. S. Peak, M. Peters, L. E. Piilonen, E. Prebys, J. Raaf, J. L. Rodriguez, N. Root, M. Rozanska, K. Rybicki, J. Ryuko, H. Sagawa, Y. Sakai, H. Sakamoto, H. Sakaue, M. Satapathy, N. Sato, A. Satpathy, S. Schrenk, S. Semenov, M. E. Sevior, H. Shibuya, B. Shwartz, A. Sidorov, V. Sidorov, S. Stanic̆, A. Sugi, A. Sugiyama, K. Sumisawa, T. Sumiyoshi, J. Suzuki, K. Suzuki, S. Suzuki, S. Y. Suzuki, S. K. Swain, H. Tajima, T. Takahashi, F. Takasaki, M. Takita, K. Tamai, N. Tamura, J. Tanaka, M. Tanaka, Y. Tanaka, G. N. Taylor, Y. Teramoto, M. Tomoto, T. Tomura, S. N. Tovey, K. Trabelsi, T. Tsuboyama, Y. Tsujita, T. Tsukamoto, S. Uehara, K. Ueno, N. Ujiie, Y. Unno, S. Uno, Y. Ushiroda, Y. Usov, S. E. Vahsen, G. Varner, K. E. Varvell, C. C. Wang, C. H. Wang, M.-Z. Wang, T. J. Wang, Y. Watanabe, E. Won, B. D. Yabsley, Y. Yamada, M. Yamaga, A. Yamaguchi, H. Yamaguchi, H. Yamaoka, Y. Yamaoka, Y. Yamashita, M. Yamauchi, S. Yanaka, M. Yokoyama, K. Yoshida, Y. Yusa, H. Yuta, C. C. Zhang, H. W. Zhao, Y. Zheng, V. Zhilich, and D. Z̆ontar

Subjects
Physics, Nuclear physics, Particle physics, KEKB, Muon, Mixing (mathematics), Time evolution, General Physics and Astronomy
Abstract

We report a determination of the ${B}_{d}^{0}\ensuremath{-}{\overline{B}}_{d}^{0}$ mixing parameter $\ensuremath{\Delta}{m}_{d}$ based on the time evolution of dilepton yields in $\ensuremath{\Upsilon}(4S)$ decays. The measurement is based on a $5.9{\mathrm{fb}}^{\ensuremath{-}1}$ data sample collected by the Belle detector at KEKB. The proper-time difference distributions for same-sign and opposite-sign dilepton events are simultaneously fitted to an expression containing $\ensuremath{\Delta}{m}_{d}$ as a free parameter. Using both muons and electrons, we obtain $\ensuremath{\Delta}{m}_{d}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0.463\ifmmode\pm\else\textpm\fi{}0.008(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.016(\mathrm{syst}){\mathrm{ps}}^{\ensuremath{-}1}$. This is the first determination of $\ensuremath{\Delta}{m}_{d}$ from time evolution measurements at the $\ensuremath{\Upsilon}(4S)$. We also place limits on possible $\mathrm{CPT}$ violations.

Published
2001

20. Measurement of theCPViolation Parametersin2φ1inBd0Meson Decays

Author

A. Abashian, K. Abe, I. Adachi, Byoung Sup Ahn, H. Aihara, M. Akatsu, G. Alimonti, K. Aoki, K. Asai, M. Asai, Y. Asano, T. Aso, V. Aulchenko, T. Aushev, A. M. Bakich, E. Banas, S. Behari, P. K. Behera, D. Beiline, A. Bondar, A. Bozek, T. E. Browder, B. C. K. Casey, P. Chang, Y. Chao, B. G. Cheon, S.-K. Choi, Y. Choi, Y. Doi, J. Dragic, A. Drutskoy, S. Eidelman, Y. Enari, R. Enomoto, C. W. Everton, F. Fang, H. Fujii, K. Fujimoto, Y. Fujita, C. Fukunaga, M. Fukushima, A. Garmash, A. Gordon, K. Gotow, H. Guler, R. Guo, J. Haba, T. Haji, H. Hamasaki, K. Hanagaki, F. Handa, K. Hara, T. Hara, T. Haruyama, N. C. Hastings, K. Hayashi, H. Hayashii, M. Hazumi, E. M. Heenan, Y. Higashi, Y. Higashino, I. Higuchi, T. Higuchi, T. Hirai, H. Hirano, M. Hirose, T. Hojo, Y. Hoshi, K. Hoshina, W.-S. Hou, S.-C. Hsu, H.-C. Huang, Y.-C. Huang, S. Ichizawa, Y. Igarashi, T. Iijima, H. Ikeda, K. Ikeda, K. Inami, Y. Inoue, A. Ishikawa, H. Ishino, R. Itoh, G. Iwai, M. Iwai, M. Iwamoto, H. Iwasaki, Y. Iwasaki, D. J. Jackson, P. Jalocha, H. K. Jang, M. Jones, R. Kagan, H. Kakuno, J. Kaneko, J. H. Kang, J. S. Kang, P. Kapusta, K. Kasami, N. Katayama, H. Kawai, M. Kawai, N. Kawamura, T. Kawasaki, H. Kichimi, D. W. Kim, Heejong Kim, H. J. Kim, Hyunwoo Kim, S. K. Kim, K. Kinoshita, S. Kobayashi, S. Koike, S. Koishi, Y. Kondo, H. Konishi, K. Korotushenko, P. Krokovny, R. Kulasiri, S. Kumar, T. Kuniya, E. Kurihara, A. Kuzmin, Y.-J. Kwon, M. H. Lee, S. H. Lee, C. Leonidopoulos, H.-B. Li, R.-S. Lu, Y. Makida, A. Manabe, D. Marlow, T. Matsubara, T. Matsuda, S. Matsui, S. Matsumoto, T. Matsumoto, Y. Mikami, K. Misono, K. Miyabayashi, H. Miyake, H. Miyata, L. C. Moffitt, A. Mohapatra, G. R. Moloney, G. F. Moorhead, N. Morgan, S. Mori, T. Mori, A. Murakami, T. Nagamine, Y. Nagasaka, Y. Nagashima, T. Nakadaira, T. Nakamura, E. Nakano, M. Nakao, H. Nakazawa, J. W. Nam, S. Narita, Z. Natkaniec, K. Neichi, S. Nishida, O. Nitoh, S. Noguchi, T. Nozaki, S. Ogawa, T. Ohshima, Y. Ohshima, T. Okabe, T. Okazaki, S. Okuno, S. L. Olsen, W. Ostrowicz, H. Ozaki, P. Pakhlov, H. Palka, C. S. Park, C. W. Park, H. Park, L. S. Peak, M. Peters, L. E. Piilonen, E. Prebys, J. L. Rodriguez, N. Root, M. Rozanska, K. Rybicki, J. Ryuko, H. Sagawa, S. Saitoh, Y. Sakai, H. Sakamoto, H. Sakaue, M. Satapathy, N. Sato, A. Satpathy, S. Schrenk, S. Semenov, Y. Settai, M. E. Sevior, H. Shibuya, B. Shwartz, A. Sidorov, V. Sidorov, J. B. Singh, S. Stanič, A. Sugi, A. Sugiyama, K. Sumisawa, T. Sumiyoshi, J. Suzuki, J.-I. Suzuki, K. Suzuki, S. Suzuki, S. Y. Suzuki, S. K. Swain, H. Tajima, T. Takahashi, F. Takasaki, M. Takita, K. Tamai, N. Tamura, J. Tanaka, M. Tanaka, Y. Tanaka, G. N. Taylor, Y. Teramoto, M. Tomoto, T. Tomura, S. N. Tovey, K. Trabelsi, T. Tsuboyama, Y. Tsujita, T. Tsukamoto, S. Uehara, K. Ueno, N. Ujiie, Y. Unno, S. Uno, Y. Ushiroda, Y. Usov, S. E. Vahsen, G. Varner, K. E. Varvell, C. C. Wang, C. H. Wang, M.-Z. Wang, T. J. Wang, Y. Watanabe, E. Won, B. D. Yabsley, Y. Yamada, M. Yamaga, A. Yamaguchi, H. Yamaguchi, H. Yamamoto, T. Yamanaka, H. Yamaoka, Y. Yamaoka, Y. Yamashita, M. Yamauchi, S. Yanaka, M. Yokoyama, K. Yoshida, Y. Yusa, H. Yuta, C. C. Zhang, H. W. Zhao, J. Zhang, Y. Zheng, V. Zhilich, and D. Žontar

Subjects
Physics, Particle physics, KEKB, Meson, Electron–positron annihilation, General Physics and Astronomy, Resonance, CP violation, High Energy Physics::Experiment, Standard Model
Abstract

We present a measurement of the standard model $\mathrm{CP}$ violation parameter $\mathrm{sin}2{\ensuremath{\varphi}}_{1}$ (also known as $\mathrm{sin}2\ensuremath{\beta}$) based on a $10.5{\mathrm{fb}}^{\ensuremath{-}1}$ data sample collected at the $\ensuremath{\Upsilon}(4S)$ resonance with the Belle detector at the KEKB asymmetric ${e}^{+}{e}^{\ensuremath{-}}$ collider. One neutral $B$ meson is reconstructed in the $J/\ensuremath{\psi}{K}_{S}$, $\ensuremath{\psi}(2S){K}_{S}$, ${\ensuremath{\chi}}_{c1}{K}_{S}$, ${\ensuremath{\eta}}_{c}{K}_{S}$, $J/\ensuremath{\psi}{K}_{L}$, or $J/\ensuremath{\psi}{\ensuremath{\pi}}^{0}$ $\mathrm{CP}$-eigenstate decay channel and the flavor of the accompanying $B$ meson is identified from its charged particle decay products. From the asymmetry in the distribution of the time interval between the two $B$-meson decay points, we determine $\mathrm{sin}2{\ensuremath{\varphi}}_{1}{\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0.58}_{\ensuremath{-}0.34}^{+0.32}(\mathrm{stat}{)}_{\ensuremath{-}0.10}^{+0.09}(\mathrm{syst})$.

Published
2001

21. Performance of glass RPC operated in streamer mode with SF6 gas mixture

Author

N. Kawamura, K. Neichi, Akira Yamaguchi, Y. Hoshi, H. Yuta, M. Yamaga, T. Nagamine, Y. Mikami, F. Handa, M. Ueki, Koji Abe, Y. Yusa, S. Narita, and I. Higuchi

Subjects
Physics, Nuclear and High Energy Physics, Freon, Analytical chemistry, Mode (statistics), High voltage, Plateau (mathematics), Instrumentation
Abstract

We have tested the performance of glass RPC operated in streamer mode with the gas mixture containing SF 6 instead of freon, HFC-134a. By using a small amount of SF 6 , we could operate the RPCs at a much lower high voltage with comparable performance to the HFC-134a mixture except for having a narrower efficiency plateau. The feasibility for using the SF 6 mixture is discussed.

Published
2000

22. Detection of Muons, and K0L Mesons from e+e- collisions using the endcap RPC module in the Belle detector

Author

F. Handa, Kazuo Abe, T. Takahashi, S. Chinomi, M. Yamaga, H. Hanada, H. Yuta, T. Takayama, Y. Teramoto, Akira Yamaguchi, M. Nakajima, Y. Inoue, Y. Igarashi, N. Kawamura, T. Nakajima, N. Murono, I. Higuchi, T. Nagamine, S. Narita, S. Azuchi, H. Sakaue, Y. Hoshi, E. Nakano, K. Watanabe, and K. Neichi

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Luminosity (scattering theory), Muon, Meson, Hadron, Detector, Particle detector, Belle experiment, Nuclear physics, KEKB, Nuclear Energy and Engineering, Electrical and Electronic Engineering
Abstract

The Belle experiment at the KEKB has collected beam collision data from June 1st through August 4th, 1999, integrated luminosity during this period is 25 pb/sup -1/, and the data contain approximately 10,000 e/sup +/e/sup -//spl rarr//spl mu//sup +//spl mu//sup $/events and 50,000 hadronic events. Using those events, we study the performance of endcap RPC modules in the Belle detector. The study shows that the endcap RPC modules perform quite well in detecting muons and K/sub L//sup 0/ mesons.

Published
2000

23. RPC systems for BELLE detector at KEKB

Author

M Yamaga, A Abashian, K Abe, P.K Behera, S Chidzik, K Gotow, K Hanagaki, Y Hoshi, Y Inoue, N Kawamura, K Korotushenko, D Marlow, N Morgan, T Nagamine, E Nakano, S Narita, K Neichi, L Piilonen, E Prebys, W Sands, S Schrenk, T Takahashi, Y Teramoto, A Yamaguchi, and H Yuta

Subjects
Physics, Nuclear and High Energy Physics, Muon, Physics::Instrumentation and Detectors, Detector, Readout electronics, Cosmic ray, Belle experiment, Nuclear physics, KEKB, Data acquisition, High Energy Physics::Experiment, Instrumentation, Yoke
Abstract

We constructed glass RPC modules for detecting K L and muon in BELLE experiment. The modules have been installed in the instrumented iron yoke outside of the solenoid coil and cover about 2000 m 2 of detectors. We report the design and construction of the detectors, including the gas distribution and exhaust system, the HV system, the readout electronics and DAQ system. The performance with cosmic ray and the e + e − collision data are presented.

Published
2000

24. Construction and performance of multigap RPC in streamer and avalanche modes

Author

K. Neichi, Akira Yamaguchi, Y. Hoshi, and S. Narita

Subjects
Physics, Avalanche mode, Nuclear and High Energy Physics, Multigap, Muon, Physics::Instrumentation and Detectors, business.industry, Counting efficiency, Resistive plate chamber, Time resolution, Signal, Optics, Time response, RPC, Avalanche, business, Streamer, Instrumentation
Abstract

We have constructed the multigap RPC and investigated its performance in counting efficiency and the time response for the cosmic-ray muons. The multigap structure of resistive plate chamber (RPC) is supposed to be helpful to obtain reasonably large signal without degrading the time resolution. We found that an average time resolution for 3 gap RPC in avalanche mode was about 0.48 ns. The time resolution is considered to be inversely proportional to the gap size.

Published
2009

25. Cosmic-ray test of the installed endcap RPC modules in BELLE detector

Author

K. Abe, S. Azuchi, H. Hanada, F. Haitani, Y. Hoshi, Y. Igarashi, Y. Inoue, N. Kawamura, T. Nagamine, M. Nakajima, T. Nakajima, E. Nakano, S. Narita, K. Neichi, H. Sakai, T. Takahashi, T. Takayama, Y. Teramoto, M. Ueki, M. Yamaga, A. Yamaguchi, and H. Yuta

Subjects
Physics, Nuclear and High Energy Physics, Resistive touchscreen, Muon, Detector, Particle accelerator, Cosmic ray, Particle detector, Particle identification, law.invention, Nuclear physics, KEKB, Nuclear Energy and Engineering, law, Electrical and Electronic Engineering
Abstract

In BELLE detector at KEKB, the resistive plate counter (RPC) modules were constructed for the muon trigger and K/sub L//sup 0/ detection. The endcap quadrant consisting of 14 superlayer RPC modules alternating with 47 mm thick iron plates and the 112 endcap modules have been installed in BELLE detector. We study on the tracking performance of the installed endcap RPC modules using by cosmic-ray test for the whole BELLE detector system.

Published
1999

26. Performance of resistive plate counter with non-ozone depletion freon

Author

Akira Yamaguchi, T. Nakajima, K. Neichi, K. Nanba, T. Nagamine, Y. Hoshi, H. Kawasaki, M. Ichinose, M. Yamada, T. Takayama, N. Kawamura, M. Sanpei, H. Yuta, Kazuo Abe, and M. Yamaga

Subjects
Quenching, Nuclear and High Energy Physics, Argon, Freon, Materials science, Analytical chemistry, chemistry.chemical_element, Ozone depletion potential, Ozone depletion, Particle detector, Nuclear physics, chemistry.chemical_compound, Nuclear Energy and Engineering, chemistry, Isobutane, Electrical and Electronic Engineering, Dark current
Abstract

The standard gas mixture used for RPCs contains /spl sim/60% Ar, /spl sim/40% isoC/sub 4/H/sub 10/ and several percent of CF/sub 3/Br (Haron1301) as quenching agent. CF/sub 3/Br is known to destroy the atmospheric ozone layer. For this reason its use is discouraged, and prohibited by law in the near future. C/sub 2/F/sub 6/ (FC116) and C/sub 2/H/sub 2/F/sub 4/ (HFC134A) seem to be an ideal candidate from an environment point of view since its ozone depletion potential is very low. We present the results of a test performance on RPC (glass) operating with non-ozone depletion freon gas and butane-silver.

Published
1997

27. A study of non-flammable gas mixture for resistive plate counter

Author

K. Neichi, Y. Hoshi, H. Yuta, T. Nakajima, N. Kawamura, T. Takayama, H. Kawasaki, H. Takamatsu, M. Ishikawa, T. Nagamine, Akira Yamaguchi, and Kazuo Abe

Subjects
Flammable liquid, Physics, Nuclear and High Energy Physics, Resistive touchscreen, Freon, Muon, Argon, Analytical chemistry, chemistry.chemical_element, Conductivity, Spectral line, Nuclear physics, chemistry.chemical_compound, Nuclear Energy and Engineering, chemistry, Electrode, Electrical and Electronic Engineering
Abstract

The RPC (resistive plate counter) has good time and position resolution. These factors make it an attractive candidate for trigger system at collider experiment. The standard gas mixtures (Ar+iso-C/sub 4/H/sub 10/+Freon) used in RPC are very flammable when leaked into air. In view of safety issue,we have studied non-flammable gas of Ar+CO/sub 2/+iso-C/sub 4/H/sub 10/+Freon as a function of ratio Ar:CO/sub 2/ allowed in non-flammable gas mixtures for the RPC with ABS electrodes. The basic performance of the various mixtures have been measured; singles (untriggered) count rate, detection efficiency and charge spectra versus operating voltage. We have found a set of non-flammable mixtures of the kind of Ar+CO/sub 2/+Freon contained less than /spl sim/8.4% of iso-C/sub 4/H/sub 10/ for K/sub L//muon counter of KEK B-factory at KEK.

Published
1996

29. Characteristics of an ionization chamber using tetramethylgermanium

Author

Nobuaki Kawamura, F. Suekane, Y. Hasegawa, Kazuo Hasegawa, Y. Iwasaki, H. Hanada, K. Neichi, H. Yuta, J. Katayama, Koji Abe, K. Suzuki, Ryusaburo Kikuchi, K. Ishimaru, Masato Higuchi, M. Kuriki, Kimiaki Masuda, T. Nakajima, Kazumasa Miyano, Y. Hoshi, H. Iso, and M. Sakamoto

Subjects
Physics, Nuclear and High Energy Physics, Yield (engineering), Electron lifetime, macromolecular substances, Radiation, law.invention, Magazine, law, Electrical resistivity and conductivity, Ionization, Ionization chamber, Irradiation, Atomic physics, Instrumentation
Abstract

The material compatibility and the radiation resistivity of liquid tetramethylgermanium have been examined by monitoring the ionization yield and the electron lifetime in a pulse ionization chamber. There is no deterioration of the liquid quality with hardened lead during one year. Irradiation with 1000 Gy of γ-rays causes some deterioration of the liquid. The electron lifetime for the damage liquid was almost restored to its initial value by repeating the purification several times.

Published
1993

30. Measurements of streamer and avalanche size by using RPC with submilli-strips

Author

Y. Hoshi, D. Miura, S. Narita, Y. Kikuchi, Akira Yamaguchi, and K. Neichi

Subjects
Physics, Argon, Physics::Instrumentation and Detectors, business.industry, chemistry.chemical_element, Cosmic ray, STRIPS, Tracking (particle physics), law.invention, Distance measurement, Optics, chemistry, Physics::Plasma Physics, law, Electrode, Scintillation counter, business, Image resolution
Abstract

The study of streamer and avalanche size can give us information on the spatial distribution of the charge on the electrode. It is necessary to understand the charge spread to design and develop a new tracking/imaging device with RPC. We have measured the size of streamer and avalanche induced by cosmic rays in the RPC using the submilli-size readout strips. In the configuration used in this study, the streamer size was measured to be about 10 mm. This spatial distribution somewhat depends on the gas mixtures.

Published
2008

31. Experimental Constraints on the Spin and Parity of theΛc(2880)+

Author

Masashi Hazumi, S. Cole, Masahiro Fujikawa, L. S. Peak, K. Tanabe, P. Goldenzweig, J. S. H. Lee, R. Dowd, J. S. Kang, Takashi Kubota, Y. Uchida, G. R. Moloney, M. Grosse Perdekamp, N. Tamura, H. Stoeck, P. Krizan, H. Sahoo, B. Golob, James Mueller, A.E. Bondar, P. Krokovny, Z. Natkaniec, T. Uglov, Yoji Hasegawa, C. W. Park, E. Won, H. Sakaue, Y.T. Tsai, Yu Nakahama, Daniel Robert Marlow, Marco Barbero, K. Trabelsi, S. Banerjee, A. Murakami, Y. Iwasaki, V.N. Zhilich, W. A. Mitaroff, Young-Il Choi, K. Miyabayashi, B. Shwartz, T. Ziegler, Y. J. Kwon, O. Schneider, M. Yamauchi, Tariq Aziz, N. Kikuchi, Seema Bahinipati, R. Seidl, K. Hoshina, S. Nishida, Tapas Sarangi, M. Rozanska, Kevin Varvell, M. Shapkin, K. Aoki, M. Dash, J.H. Choi, Y. Choi, M. Iwabuchi, D. Epifanov, M. Starič, Yuji Enari, T. Higuchi, T. Seki, H. Nakazawa, G. Gokhroo, T. Hara, A. J. Schwartz, A. Matyja, Ilija Bizjak, V.A. Sidorov, M. Z. Wang, K. Kinoshita, S. Saitoh, Y.-T. Shen, K. Uchida, T. Aushev, R. Mizuk, Y.-J. Lee, V. M. Aulchenko, D. Anipko, H. Guler, S. Yoshino, K. S. Park, Antonio Limosani, N. Soni, M. C. Chang, Kimitaka Itoh, A. Kuzmin, J. S. Lange, J. Dragic, Vladislav Balagura, S. L. Olsen, H. Fujii, T. Mori, E. L. Barberio, Rakesh Kumar, Y. Usov, Y. F. Liu, Hiroshi Sakamoto, N. Takada, H. Palka, L. E. Piilonen, M. Bračko, S. Fratina, G. N. Taylor, T. Schietinger, Z. P. Zhang, G. Pakhlova, R. Kulasiri, S. Ogawa, S. Ono, Y. Igarashi, C. C. Wang, M. Pernicka, T. Matsumoto, W. S. Hou, W. Ostrowicz, A. Go, I. Adachi, K. Arinstein, Y. Mikami, E. Nakano, Y. Ushiroda, Y. Sakai, Sadaharu Uehara, E. Kurihara, Akito Kusaka, H. Miyake, R. Chistov, H. O. Kim, Y.F. Tse, A. Somov, Jie Zhang, A. Yamaguchi, Samo Stanič, A. Kibayashi, S. Uno, C. Schwanda, K. Inami, A. Imoto, S. R. Hou, M. Nakao, I. Bedny, J. Li, Gobinda Majumder, S. Noguchi, S. McOnie, S. Y. Suzuki, A. M. Bakich, T. Ohshima, J. MacNaughton, Anton Poluektov, Osamu Tajima, K. Nishimura, T. Tsukamoto, J. B. Singh, S. K. Choi, T. E. Browder, N. Gabyshev, You-Jin Yuan, K. Sumisawa, S. Villa, Y. Miyazaki, N. Satoyama, P. Schonmeier, T. J. Gershon, K. Neichi, A. Zupanc, A. Chuvikov, L. Hinz, H. Hayashii, Hyunyong Kim, S. L. Blyth, T. Hokuue, A. Sokolov, K. Ikado, M. Danilov, C. C. Kuo, O. Nitoh, I. Nakamura, Y. Kozakai, Y. Ban, K. Hara, Y. Yusa, S. U. Kataoka, T. Sumiyoshi, Jeremy Dalseno, Y. B. Hsiung, K. Sayeed, S. Eidelman, C.Y. Lin, N. Parslow, L. Widhalm, P. Pakhlov, H. Miyata, N. C. Hastings, Y. Hoshi, J. Schümann, Matthew Jones, K. Hayasaka, H. Park, A. Bozek, M. H. Tanaka, C. H. Wang, U. Bitenc, T.H. Kim, A. Drutskoy, Y. J. Kim, Hiroaki Aihara, Tatiana Medvedeva, Phillip Urquijo, H. Ozaki, C. Z. Yuan, Rainer Stamen, D. Mohapatra, I. Tikhomirov, H. Ha, M. Iwasaki, N. Katayama, C. C. Zhang, B. G. Cheon, H. Shibuya, M. Watanabe, M. D. Peters, J. Haba, L.M. Zhang, Frederic Jean Ronga, Y. Yamashita, R. Pestotnik, K. Belous, S. Korpar, Jolanta Brodzicka, H. Yamamoto, T. Nagamine, Nobuaki Sato, Shimpei Yamamoto, Y. Chao, C. Jacoby, N. Kishimoto, H. R. Khan, S. K. Kim, A. Chen, Toru Iijima, Y. Unno, Kazuo Abe, Y. Asano, P. Kapusta, S. Okuno, A. Ogawa, Andrej Gorišek, A. Garmash, Hirokazu Ishino, A. Ishikawa, Y. Teramoto, Bruce Yabsley, A. Bay, S.L. Zang, T. Okabe, Yasushi Nagasaka, S. E. Lee, T. Nozaki, S. W. Lin, F. Takasaki, D. Liventsev, N.I. Root, G. S. Varner, W. T. Chen, P. Chang, J. Wicht, Jung-Hyun Kim, R. Itoh, Q. L. Xie, Tsukasa Aso, T. Nakagawa, T. Arakawa, H. Kakuno, Kai-Feng Chen, K. Senyo, K. Ueno, T. Kawasaki, D. Zurcher, J. H. Kang, A. Sugiyama, Jamal Rorie, X. C. Tian, D. Heffernan, C.-H. Wu, Y. Watanabe, H. Kichimi, T. Tsuboyama, T. Lesiak, J. Wiechczynski, G. Leder, F. Mandl, K. Tamai, and M. E. Sevior

Subjects
Physics, Particle decay, Crystallography, Annihilation, KEKB, TheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITY, Electron–positron annihilation, General Physics and Astronomy, Resonance, Continuum (set theory), Lambda, Quantum number
Abstract

We report the results of several studies of the {lambda}{sub c}{sup +}{pi}{sup +}{pi}{sup -}X final state in continuum e{sup +}e{sup -} annihilation data collected by the Belle detector. An analysis of angular distributions in {lambda}{sub c}(2880){sup +}{yields}{sigma}{sub c}(2455){sup 0,++}{pi}{sup +,-} decays strongly favors a {lambda}{sub c}(2880){sup +} spin assignment of (5/2) over (3/2) or (1/2). We find evidence for {lambda}{sub c}(2880){sup +}{yields}{sigma}{sub c}(2520){sup 0,++}{pi}{sup +,-} decay and measure the ratio of {lambda}{sub c}(2880){sup +} partial widths {gamma}({sigma}{sub c}(2520){pi})/{gamma}({sigma}{sub c}(2455){pi})=0.225{+-}0.062{+-}0.= 025. This value favors the {lambda}{sub c}(2880){sup +} spin-parity assignment of (5/2){sup +} over (5/2){sup -}. We also report the first observation of {lambda}{sub c}(2940){sup +}{yields}{sigma}{sub c}(2455){sup 0,++}{pi}{sup +,-} decay and measure {lambda}{sub c}(2880){sup +} and {lambda}{sub c}(2940){sup +} mass and width parameters. These studies are based on a 553 fb{sup -1} data sample collected at or near the {upsilon}(4S) resonance at the KEKB collider.

Published
2007

32. Optical observation of 3D streamer image in resistive plate counter

Author

K. Neichi, H. Yuta, K. Onodera, Y. Hoshi, T. Nagamine, K. Kumagai, N. Takahashi, Takahashi Tatsuto, Akira Yamaguchi, and Kazuo Abe

Subjects
Physics, Resistive touchscreen, Optics, Ccd camera, law, business.industry, Image intensifier, Pickup, business, Gas mixing, Optical observation, law.invention, Image (mathematics)
Abstract

3D streamer image in a resistive plate counter (RPC) were taken by using a glass RPC, an image intensifier and a CCD camera. Observations were simultaneously made for self-discharge in top and side view, operated in the streamer mode with various gas mixtures(Ar/butane/HFC134a). The analysis of the streamer image might be useful for us to design the pickup strip width for the readout. We report on a shape of the streamer in the top and side view as a function of gas mixing ratio.

Published
2005

33. Performance of rate capability for glass RPC operated in streamer mode with nitrogen laser beam

Author

K. Neichi, M. Kumagai, Y. Hoshi, Kazuo Abe, Akira Yamaguchi, H. Yuta, and H. Hayasaka

Subjects
Physics, Optics, Drift velocity, Physics::Instrumentation and Detectors, business.industry, Nitrogen laser, Electronics, Diffusion (business), business, Tracking (particle physics), Signal, Belle experiment, Beam (structure)
Abstract

Resistive plate chamber (RPC) has attracted high-energy and cosmic-ray experiment since its introduction in early 1980's because of high efficiency, good time resolution, tracking capability and low cost. From these features, RPCs have been chosen as the muon detector for Belle experiment at KEK. The RPCs have two operation mode; avalanche and streamer mode. The avalanche mode has an advantage that it offers in terms of rate capability to compare with the streamer mode. But, the streamer mode is still preferred for high-energy experiment, mainly for its characteristics of giving large and saturated signal that makes the front-end electronics simple and the experiment operation easy. From this point of view, we have to study the rate capability of the streamer for a glass RPC with nitrogen laser beam. Furthermore, we are going to study the fundamental gas properties of streamer, drift velocity, diffusion, and electron attachment in the glass RPC. In this conference, we report the preliminary results of the rate capability of the glass RPC operated in streamer mode with nitrogen laser beam. The results provide us more knowledge of the rate capability for the streamer mode operation.

Published
2005

34. A high rate gas mixture for glass RPC operated in streamer mode

Author

M. Kumagai, S. Ando, T. Fujikawa, K. Neichi, T. Nagamine, H. Hayasaka, Y. Hoshi, Akira Yamaguchi, and N. Kikuchi

Subjects
High rate, Physics, Argon, KEKB, chemistry, Ionization chamber, Electrode, Analytical chemistry, chemistry.chemical_element, Neutron, Beam (structure), Helium
Abstract

In Belle, glass RPCs have operated in streamer mode with the Belle standard gas mixture. However, efficiencies of RPCs for the outermost few layers of the endcap region decrease from /spl sim/95% to /spl sim/50% due to hit-rate of 1.4 Hz/cm/sup 2/ from neutron background originated from KEKB with higher beam current operation. To operate efficiently glass RPCs at this high background rate, high rate gas mixtures using SF/sub 6/ have been tested. We report the performance of glass RPC.

Published
2005

35. Evidence for DirectCPViolation inB0→K+π−Decays

Author

Y. Chao, P. Chang, K. Abe, N. Abe, I. Adachi, H. Aihara, K. Akai, M. Akatsu, M. Akemoto, Y. Asano, T. Aso, V. Aulchenko, T. Aushev, T. Aziz, S. Bahinipati, A. M. Bakich, Y. Ban, M. Barbero, A. Bay, I. Bedny, U. Bitenc, I. Bizjak, S. Blyth, A. Bondar, A. Bozek, M. Bračko, J. Brodzicka, T. E. Browder, M.-C. Chang, A. Chen, K.-F. Chen, W. T. Chen, B. G. Cheon, R. Chistov, S.-K. Choi, Y. Choi, Y. K. Choi, A. Chuvikov, S. Cole, M. Danilov, M. Dash, L. Y. Dong, R. Dowd, J. Dragic, A. Drutskoy, S. Eidelman, V. Eiges, Y. Enari, D. Epifanov, C. W. Everton, F. Fang, J. Flanagan, S. Fratina, H. Fujii, Y. Funakoshi, K. Furukawa, N. Gabyshev, A. Garmash, T. Gershon, A. Go, G. Gokhroo, B. Golob, M. Grosse Perdekamp, H. Guler, R. Guo, J. Haba, C. Hagner, F. Handa, K. Hara, T. Hara, N. C. Hastings, K. Hasuko, K. Hayasaka, H. Hayashii, M. Hazumi, E. M. Heenan, I. Higuchi, T. Higuchi, L. Hinz, T. Hojo, T. Hokuue, Y. Hoshi, K. Hoshina, S. Hou, W.-S. Hou, Y. B. Hsiung, H.-C. Huang, T. Igaki, Y. Igarashi, T. Iijima, H. Ikeda, A. Imoto, K. Inami, A. Ishikawa, H. Ishino, K. Itoh, R. Itoh, M. Iwamoto, M. Iwasaki, Y. Iwasaki, R. Kagan, H. Kakuno, T. Kamitani, J. H. Kang, J. S. Kang, P. Kapusta, S. U. Kataoka, N. Katayama, H. Kawai, Y. Kawakami, N. Kawamura, T. Kawasaki, N. Kent, H. R. Khan, A. Kibayashi, H. Kichimi, M. Kikuchi, E. Kikutani, H. J. Kim, H. O. Kim, Hyunwoo Kim, J. H. Kim, S. K. Kim, T. H. Kim, K. Kinoshita, S. Kobayashi, H. Koiso, P. Koppenburg, S. Korpar, P. Križan, P. Krokovny, T. Kubo, R. Kulasiri, S. Kumar, C. C. Kuo, H. Kurashiro, E. Kurihara, A. Kusaka, A. Kuzmin, Y.-J. Kwon, J. S. Lange, G. Leder, S. E. Lee, S. H. Lee, Y.-J. Lee, T. Lesiak, J. Li, A. Limosani, S.-W. Lin, D. Liventsev, J. MacNaughton, G. Majumder, F. Mandl, D. Marlow, M. Masuzawa, T. Matsuishi, H. Matsumoto, S. Matsumoto, T. Matsumoto, A. Matyja, S. Michizono, Y. Mikami, T. Mimashi, W. Mitaroff, K. Miyabayashi, Y. Miyabayashi, H. Miyake, H. Miyata, R. Mizuk, D. Mohapatra, G. R. Moloney, G. F. Moorhead, T. Mori, J. Mueller, A. Murakami, T. Nagamine, Y. Nagasaka, T. Nakadaira, I. Nakamura, T. T. Nakamura, E. Nakano, M. Nakao, H. Nakayama, H. Nakazawa, Z. Natkaniec, K. Neichi, S. Nishida, O. Nitoh, S. Noguchi, T. Nozaki, A. Ogawa, S. Ogawa, Y. Ogawa, K. Ohmi, Y. Ohnishi, T. Ohshima, N. Ohuchi, K. Oide, T. Okabe, S. Okuno, S. L. Olsen, Y. Onuki, W. Ostrowicz, H. Ozaki, P. Pakhlov, H. Palka, C. W. Park, H. Park, K. S. Park, N. Parslow, L. S. Peak, M. Pernicka, J.-P. Perroud, M. Peters, L. E. Piilonen, A. Poluektov, F. J. Ronga, N. Root, M. Rozanska, H. Sagawa, M. Saigo, S. Saitoh, Y. Sakai, H. Sakamoto, H. Sakaue, T. R. Sarangi, M. Satapathy, N. Sato, T. Schietinger, O. Schneider, J. Schümann, C. Schwanda, A. J. Schwartz, T. Seki, S. Semenov, K. Senyo, Y. Settai, R. Seuster, M. E. Sevior, T. Shibata, H. Shibuya, T. Shidara, B. Shwartz, V. Sidorov, V. Siegle, J. B. Singh, A. Somov, N. Soni, R. Stamen, S. Stanič, M. Starič, R. Sugahara, A. Sugi, T. Sugimura, A. Sugiyama, K. Sumisawa, T. Sumiyoshi, S. Suzuki, S. Y. Suzuki, S. K. Swain, O. Tajima, F. Takasaki, K. Tamai, N. Tamura, K. Tanabe, M. Tanaka, M. Tawada, G. N. Taylor, Y. Teramoto, X. C. Tian, S. Tokuda, S. N. Tovey, K. Trabelsi, T. Tsuboyama, T. Tsukamoto, K. Uchida, S. Uehara, T. Uglov, K. Ueno, Y. Unno, S. Uno, Y. Ushiroda, G. Varner, K. E. Varvell, S. Villa, C. C. Wang, C. H. Wang, J. G. Wang, M.-Z. Wang, M. Watanabe, Y. Watanabe, L. Widhalm, Q. L. Xie, B. D. Yabsley, A. Yamaguchi, H. Yamamoto, N. Yamamoto, S. Yamamoto, T. Yamanaka, Y. Yamashita, M. Yamauchi, Heyoung Yang, P. Yeh, J. Ying, K. Yoshida, M. Yoshida, Y. Yuan, Y. Yusa, H. Yuta, S. L. Zang, C. C. Zhang, J. Zhang, L. M. Zhang, Z. P. Zhang, Y. Zheng, V. Zhilich, T. Ziegler, D. Žontar, and D. Zürcher

Subjects
Physics, Nuclear physics, Particle physics, KEKB, law, Electron–positron annihilation, General Physics and Astronomy, CP violation, Collider, Mixing (physics), Charged particle, law.invention
Abstract

The evidence for direct charged particles (CP) violation in the decay B0→K+ π- was investigated with 253 fb-1 of data collected with the Belle detector at the KEKB e + e- collider. 275 x 106 BB pairs were used to observe a B→K±π∓ signal with 2140 ±53 events. Mixing induced CP violation in the B sector was established in b → ccs transitions. The result suggests large interference between tree and penguin diagrams and the existence of final state interactions.

Published
2004

36. Inclusive Measurement of the Photon Energy Spectrum inb→sγDecays

Author

P. Koppenburg, K. Abe, T. Abe, I. Adachi, H. Aihara, M. Akatsu, Y. Asano, V. Aulchenko, T. Aushev, A. M. Bakich, Y. Ban, A. Bay, U. Bitenc, I. Bizjak, A. Bondar, A. Bozek, M. Bračko, T. E. Browder, P. Chang, Y. Chao, K.-F. Chen, B. G. Cheon, Y. Choi, A. Chuvikov, S. Cole, M. Danilov, M. Dash, L. Y. Dong, A. Drutskoy, S. Eidelman, V. Eiges, Y. Enari, F. Fang, S. Fratina, N. Gabyshev, A. Garmash, T. Gershon, G. Gokhroo, B. Golob, J. Haba, H. Hayashii, M. Hazumi, T. Higuchi, L. Hinz, T. Hokuue, Y. Hoshi, W.-S. Hou, Y. B. Hsiung, T. Iijima, K. Inami, A. Ishikawa, R. Itoh, H. Iwasaki, M. Iwasaki, J. H. Kang, J. S. Kang, N. Katayama, H. Kawai, T. Kawasaki, H. Kichimi, H. J. Kim, J. H. Kim, S. K. Kim, T. H. Kim, S. Korpar, P. Križan, P. Krokovny, S. Kumar, A. Kuzmin, Y.-J. Kwon, J. S. Lange, G. Leder, S. H. Lee, T. Lesiak, J. Li, A. Limosani, S.-W. Lin, J. MacNaughton, G. Majumder, F. Mandl, T. Matsumoto, Y. Mikami, W. Mitaroff, K. Miyabayashi, H. Miyake, H. Miyata, D. Mohapatra, G. R. Moloney, T. Mori, T. Nagamine, Y. Nagasaka, T. Nakadaira, E. Nakano, M. Nakao, Z. Natkaniec, K. Neichi, S. Nishida, O. Nitoh, T. Nozaki, S. Ogawa, T. Ohshima, T. Okabe, S. Okuno, S. L. Olsen, W. Ostrowicz, H. Ozaki, P. Pakhlov, H. Palka, C. W. Park, H. Park, N. Parslow, L. S. Peak, L. E. Piilonen, F. J. Ronga, M. Rozanska, H. Sagawa, S. Saitoh, Y. Sakai, T. R. Sarangi, O. Schneider, C. Schwanda, A. J. Schwartz, S. Semenov, K. Senyo, R. Seuster, M. E. Sevior, H. Shibuya, N. Soni, R. Stamen, S. Stanič, M. Starič, T. Sumiyoshi, S. Suzuki, O. Tajima, F. Takasaki, N. Tamura, M. Tanaka, G. N. Taylor, T. Tomura, K. Trabelsi, T. Tsuboyama, T. Tsukamoto, S. Uehara, T. Uglov, K. Ueno, S. Uno, Y. Ushiroda, G. Varner, K. E. Varvell, C. C. Wang, C. H. Wang, M. Watanabe, B. D. Yabsley, Y. Yamada, A. Yamaguchi, Y. Yamashita, M. Yamauchi, H. Yanai, Heyoung Yang, J. Ying, Y. Yusa, C. C. Zhang, Z. P. Zhang, T. Ziegler, and D. Žontar

Subjects
Combinatorics, Physics, Particle physics, Electron–positron annihilation, Spectrum (functional analysis), General Physics and Astronomy, B meson, Photon energy, Energy (signal processing)
Abstract

We report a fully inclusive measurement of the flavor changing neutral current decay $b\ensuremath{\rightarrow}s\ensuremath{\gamma}$ in the energy range $1.8\text{ }\mathrm{G}\mathrm{e}\mathrm{V}\ensuremath{\le}{E}_{\ensuremath{\gamma}}^{*}\ensuremath{\le}2.8\text{ }\mathrm{G}\mathrm{e}\mathrm{V}$, covering 95% of the total spectrum. Using $140\text{ }\mathrm{f}{\mathrm{b}}^{\mathrm{\ensuremath{-}}\mathrm{1}}$, we obtain $\mathcal{B}(b\ensuremath{\rightarrow}s\ensuremath{\gamma})=(3.55\ifmmode\pm\else\textpm\fi{}{0.32}_{\ensuremath{-}0.31\ensuremath{-}0.07}^{+0.30+0.11})\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$, where the errors are statistical, systematic, and from theory corrections. We also measure the first and second moments of the photon energy spectrum above $1.8\text{ }\mathrm{G}\mathrm{e}\mathrm{V}$ and obtain $\ensuremath{\langle}{E}_{\ensuremath{\gamma}}\ensuremath{\rangle}=2.292\ifmmode\pm\else\textpm\fi{}0.026\ifmmode\pm\else\textpm\fi{}0.034\text{ }\mathrm{G}\mathrm{e}\mathrm{V}$ and $\ensuremath{\langle}{E}_{\ensuremath{\gamma}}^{2}\ensuremath{\rangle}\ensuremath{-}\ensuremath{\langle}{E}_{\ensuremath{\gamma}}{\ensuremath{\rangle}}^{2}=0.0305\ifmmode\pm\else\textpm\fi{}0.0074\ifmmode\pm\else\textpm\fi{}0.0063\text{ }{\mathrm{G}\mathrm{e}\mathrm{V}}^{2}$, where the errors are statistical and systematic.

Published
2004

37. Observation of LargeCPViolation and Evidence for DirectCPViolation inB0→π+π−Decays

Author

K. Abe, N. Abe, T. Abe, I. Adachi, H. Aihara, K. Akai, M. Akatsu, M. Akemoto, Y. Asano, T. Aso, V. Aulchenko, T. Aushev, A. M. Bakich, Y. Ban, S. Banerjee, A. Bay, I. Bedny, I. Bizjak, A. Bondar, A. Bozek, M. Bračko, T. E. Browder, Y. Chao, K.-F. Chen, B. G. Cheon, R. Chistov, S.-K. Choi, Y. Choi, A. Chuvikov, S. Cole, M. Danilov, J. Dragic, A. Drutskoy, S. Eidelman, V. Eiges, Y. Enari, D. Epifanov, J. Flanagan, K. Furukawa, N. Gabyshev, A. Garmash, T. Gershon, B. Golob, J. Haba, K. Hara, N. C. Hastings, H. Hayashii, M. Hazumi, L. Hinz, T. Hokuue, Y. Hoshi, W.-S. Hou, Y. B. Hsiung, H.-C. Huang, T. Iijima, H. Ikeda, K. Inami, A. Ishikawa, H. Ishino, R. Itoh, H. Iwasaki, M. Iwasaki, Y. Iwasaki, H. Kakuno, T. Kamitani, J. H. Kang, J. S. Kang, P. Kapusta, S. U. Kataoka, N. Katayama, H. Kawai, T. Kawasaki, A. Kibayashi, H. Kichimi, E. Kikutani, H. J. Kim, J. H. Kim, S. K. Kim, K. Kinoshita, P. Koppenburg, S. Korpar, P. Križan, P. Krokovny, S. Kumar, A. Kuzmin, Y.-J. Kwon, J. S. Lange, G. Leder, S. H. Lee, Y.-J. Lee, T. Lesiak, J. Li, A. Limosani, S.-W. Lin, D. Liventsev, J. MacNaughton, F. Mandl, D. Marlow, H. Matsumoto, T. Matsumoto, A. Matyja, S. Michizono, T. Mimashi, W. Mitaroff, K. Miyabayashi, H. Miyake, H. Miyata, D. Mohapatra, G. R. Moloney, A. Murakami, T. Nagamine, Y. Nagasaka, T. Nakadaira, T. T. Nakamura, E. Nakano, M. Nakao, H. Nakazawa, Z. Natkaniec, K. Neichi, S. Nishida, O. Nitoh, S. Noguchi, T. Nozaki, S. Ogawa, Y. Ogawa, K. Ohmi, T. Ohshima, N. Ohuchi, K. Oide, T. Okabe, S. Okuno, S. L. Olsen, W. Ostrowicz, H. Ozaki, P. Pakhlov, H. Palka, C. W. Park, H. Park, N. Parslow, L. E. Piilonen, N. Root, M. Rozanska, H. Sagawa, Y. Sakai, O. Schneider, J. Schümann, C. Schwanda, A. J. Schwartz, S. Semenov, K. Senyo, H. Shibuya, T. Shidara, B. Shwartz, V. Sidorov, J. B. Singh, N. Soni, R. Stamen, S. Stanič, M. Starič, R. Sugahara, K. Sumisawa, T. Sumiyoshi, K. Suzuki, S. Suzuki, O. Tajima, F. Takasaki, K. Tamai, N. Tamura, M. Tanaka, M. Tawada, Y. Teramoto, T. Tomura, T. Tsuboyama, T. Tsukamoto, S. Uehara, T. Uglov, K. Ueno, Y. Unno, S. Uno, G. Varner, K. E. Varvell, C. C. Wang, C. H. Wang, M.-Z. Wang, Y. Watanabe, B. D. Yabsley, Y. Yamada, A. Yamaguchi, Y. Yamashita, M. Yamauchi, H. Yanai, Heyoung Yang, J. Ying, M. Yokoyama, M. Yoshida, Y. Yusa, C. C. Zhang, Z. P. Zhang, T. Ziegler, D. Žontar, and D. Zürcher

Subjects
Nuclear physics, Physics, Particle physics, Electron–positron annihilation, General Physics and Astronomy, CP violation, B meson
Abstract

The CP violation parameters in Bo → π +π- decay were investigated. The flavor of the accompanying B meson was identified by reconstructing B o→π+π- CP eigenstate. It was observed that the expected sensitivity was optimized using the ratio LR. The study showed that there was a direct CP violation with a significance at or greater than 3.2σ.

Published
2004

38. Measurement of theB→K*γbranching fractions and asymmetries

Author

M. Nakao, K. Abe, T. Abe, I. Adachi, H. Aihara, M. Akatsu, Y. Asano, T. Aso, V. Aulchenko, T. Aushev, S. Bahinipati, A. M. Bakich, Y. Ban, A. Bay, U. Bitenc, I. Bizjak, A. Bondar, A. Bozek, M. Bračko, T. E. Browder, P. Chang, Y. Chao, K.-F. Chen, B. G. Cheon, R. Chistov, Y. Choi, A. Chuvikov, S. Cole, M. Danilov, M. Dash, L. Y. Dong, J. Dragic, A. Drutskoy, S. Eidelman, V. Eiges, Y. Enari, F. Fang, S. Fratina, N. Gabyshev, A. Garmash, T. Gershon, G. Gokhroo, B. Golob, H. Hayashii, M. Hazumi, T. Higuchi, L. Hinz, T. Hokuue, Y. Hoshi, W.-S. Hou, Y. B. Hsiung, T. Iijima, K. Inami, A. Ishikawa, H. Ishino, R. Itoh, H. Iwasaki, M. Iwasaki, J. H. Kang, J. S. Kang, N. Katayama, H. Kawai, T. Kawasaki, H. Kichimi, H. J. Kim, J. H. Kim, S. K. Kim, T. H. Kim, K. Kinoshita, P. Koppenburg, S. Korpar, P. Križan, P. Krokovny, A. Kuzmin, Y.-J. Kwon, J. S. Lange, S. H. Lee, T. Lesiak, J. Li, A. Limosani, S.-W. Lin, J. MacNaughton, G. Majumder, F. Mandl, T. Matsumoto, Y. Mikami, W. Mitaroff, K. Miyabayashi, H. Miyake, H. Miyata, D. Mohapatra, G. R. Moloney, T. Mori, T. Nagamine, Y. Nagasaka, E. Nakano, H. Nakazawa, K. Neichi, S. Nishida, O. Nitoh, T. Nozaki, S. Ogawa, T. Ohshima, T. Okabe, S. Okuno, S. L. Olsen, W. Ostrowicz, P. Pakhlov, H. Palka, H. Park, N. Parslow, L. S. Peak, L. E. Piilonen, F. J. Ronga, M. Rozanska, H. Sagawa, S. Saitoh, Y. Sakai, T. R. Sarangi, O. Schneider, J. Schümann, C. Schwanda, A. J. Schwartz, S. Semenov, K. Senyo, R. Seuster, M. E. Sevior, B. Shwartz, J. B. Singh, N. Soni, R. Stamen, S. Stanič, M. Starič, T. Sumiyoshi, S. Suzuki, O. Tajima, F. Takasaki, M. Tanaka, G. N. Taylor, Y. Teramoto, T. Tomura, T. Tsuboyama, T. Tsukamoto, S. Uehara, T. Uglov, S. Uno, Y. Ushiroda, G. Varner, K. E. Varvell, C. C. Wang, C. H. Wang, M.-Z. Wang, M. Watanabe, Y. Yamada, A. Yamaguchi, Y. Yamashita, M. Yamauchi, Heyoung Yang, J. Ying, Y. Yusa, C. C. Zhang, J. Zhang, Z. P. Zhang, V. Zhilich, T. Ziegler, and D. Žontar

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, KEKB, Electron–positron annihilation, media_common.quotation_subject, Isospin, Radiative decay, B meson, Branching (polymer chemistry), Asymmetry, media_common
Abstract

We report measurements of the radiative decay B --> K^*\gamma. The analysis is based on a data sample containing 85.0*10^6 B meson pairs collected by the Belle detector at the KEKB storage ring. We measure branching fractions of Br(B^0 --> K^{*0}\gamma) = (4.01 \pm 0.21 \pm 0.17)*10^{-5} and Br(B^+ --> K^{*+}\gamma) = (4.25 \pm 0.31 \pm 0.24)*10^{-5}, where the first and second errors are statistical and systematic, respectively. The isospin asymmetry between B^0 and B^+ decay widths is measured to be \Delta_{0+} = +0.012 \pm 0.044 \pm 0.026. We search for a partial rate asymmetry between CP conjugate modes, and find A_{cp}(B --> K^*\gamma) = =0.015 \pm 0.044 \pm 0.012.

Published
2004

39. Observation of large CP violation and evidence for direct CP violation in B0--pi(+)pi(-) decays

Author

K, Abe, N, Abe, T, Abe, I, Adachi, H, Aihara, K, Akai, M, Akatsu, M, Akemoto, Y, Asano, T, Aso, V, Aulchenko, T, Aushev, A M, Bakich, Y, Ban, S, Banerjee, A, Bay, I, Bedny, I, Bizjak, A, Bondar, A, Bozek, M, Bracko, T E, Browder, Y, Chao, K F, Chen, B G, Cheon, R, Chistov, S K, Choi, Y, Choi, A, Chuvikov, S, Cole, M, Danilov, J, Dragic, A, Drutskoy, S, Eidelman, V, Eiges, Y, Enari, D, Epifanov, J, Flanagan, K, Furukawa, N, Gabyshev, A, Garmash, T, Gershon, B, Golob, J, Haba, K, Hara, N C, Hastings, H, Hayashii, M, Hazumi, L, Hinz, T, Hokuue, Y, Hoshi, W S, Hou, Y B, Hsiung, H C, Huang, T, Iijima, H, Ikeda, K, Inami, A, Ishikawa, H, Ishino, R, Itoh, H, Iwasaki, M, Iwasaki, Y, Iwasaki, H, Kakuno, T, Kamitani, J H, Kang, J S, Kang, P, Kapusta, S U, Kataoka, N, Katayama, H, Kawai, T, Kawasaki, A, Kibayashi, H, Kichimi, E, Kikutani, H J, Kim, J H, Kim, S K, Kim, K, Kinoshita, P, Koppenburg, S, Korpar, P, Krizan, P, Krokovny, S, Kumar, A, Kuzmin, Y J, Kwon, J S, Lange, G, Leder, S H, Lee, Y J, Lee, T, Lesiak, J, Li, A, Limosani, S W, Lin, D, Liventsev, J, MacNaughton, F, Mandl, D, Marlow, H, Matsumoto, T, Matsumoto, A, Matyja, S, Michizono, T, Mimashi, W, Mitaroff, K, Miyabayashi, H, Miyake, H, Miyata, D, Mohapatra, G R, Moloney, A, Murakami, T, Nagamine, Y, Nagasaka, T, Nakadaira, T T, Nakamura, E, Nakano, M, Nakao, H, Nakazawa, Z, Natkaniec, K, Neichi, S, Nishida, O, Nitoh, S, Noguchi, T, Nozaki, S, Ogawa, Y, Ogawa, K, Ohmi, T, Ohshima, N, Ohuchi, K, Oide, T, Okabe, S, Okuno, S L, Olsen, W, Ostrowicz, H, Ozaki, P, Pakhlov, H, Palka, C W, Park, H, Park, N, Parslow, L E, Piilonen, N, Root, M, Rozanska, H, Sagawa, Y, Sakai, O, Schneider, J, Schümann, C, Schwanda, A J, Schwartz, S, Semenov, K, Senyo, H, Shibuya, T, Shidara, B, Shwartz, V, Sidorov, J B, Singh, N, Soni, R, Stamen, S, Stanic, M, Staric, R, Sugahara, K, Sumisawa, T, Sumiyoshi, K, Suzuki, S, Suzuki, O, Tajima, F, Takasaki, K, Tamai, N, Tamura, M, Tanaka, M, Tawada, Y, Teramoto, T, Tomura, T, Tsuboyama, T, Tsukamoto, S, Uehara, T, Uglov, K, Ueno, Y, Unno, S, Uno, G, Varner, K E, Varvell, C C, Wang, C H, Wang, M Z, Wang, Y, Watanabe, B D, Yabsley, Y, Yamada, A, Yamaguchi, Y, Yamashita, M, Yamauchi, H, Yanai, Heyoung, Yang, J, Ying, M, Yokoyama, M, Yoshida, Y, Yusa, C C, Zhang, Z P, Zhang, T, Ziegler, D, Zontar, and D, Zürcher

Abstract

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.

Published
2004

40. Evidence forB0→π0π0

Author

J. Tanaka, Osamu Tajima, Gobinda Majumder, Hiroyuki Iwasaki, H. Ozaki, K. Neichi, T. Tsukamoto, M. D. Peters, O. Nitoh, S. H. Lee, T. Igaki, Hiroshi Sakamoto, Hiroaki Aihara, Y. Yamashita, S. Schrenk, K. Korotushenko, A. Tchouvikov, Rong-Shyang Lu, G. R. Moloney, T. Nagamine, H. C. Huang, M. Grosse Perdekamp, N. Tamura, K. Hoshina, S. Noguchi, Y. Ushiroda, M. H. Tanaka, M. Shimoyama, S. Uno, S. E. Vahsen, C. Schwanda, N.I. Root, Y. Miyabayashi, Hiroyuki Sagawa, J. Kaneko, H. Yamamoto, Y. Kawakami, R. Guo, M. C. Chang, S. Nishida, Ascelin Gordon, S. U. Kataoka, A. Sugi, H. Fujii, J. P. Perroud, K. Hasuko, T. Iijima, Y. Onuki, L. Y. Dong, H. Kakuno, Hikaru Kawai, T. Nakadaira, E. Kurihara, Akito Kusaka, M. Kataoka, F. Ohno, C. W. Park, E. Won, P. Chang, Hyun Woo Kim, Jie Zhang, Masashi Yokoyama, E. Nakano, V.A. Sidorov, V. M. Aulchenko, Y. Ban, Jung-Hyun Kim, Y. Yusa, Daniel Robert Marlow, G. F. Moorhead, K. Trabelsi, H. K. Jang, P. Krokovny, T. Tomura, K. Senyo, Patrick Koppenburg, K. Inami, D. Mohapatra, Kyo Yoshida, J. B. Singh, Masashi Hazumi, S. K. Choi, K. Ueno, T. Kawasaki, D. Zurcher, Y. Iwasaki, V. Siegle, Y. J. Kwon, T. Sumiyoshi, H. O. Kim, R. Kagan, A. Yamaguchi, Tapas Sarangi, Frederic Jean Ronga, Takahiko Matsubara, D. Epifanov, Shaji Kumar, S. Tokuda, Kevin Varvell, Y. Chao, F. Handa, H. Miyake, S. Eidelman, Y. Settai, I. Bedny, J. Li, S. W. Lin, J. Yashima, N. Parslow, M. Iwamoto, B. Shwartz, Chikara Fukunaga, Seema Bahinipati, J. W. Nam, T. J. Gershon, P. Krizan, P. Pakhlov, D. Liventsev, O. Schneider, Z.M. Zhu, Yasuhiko Yamada, K. S. Park, Y. Choi, M. Yamauchi, T. Hojo, J. G. Wang, A. Satpathy, A. Matyja, Ilija Bizjak, T. Hara, H. Hayashii, N. Abe, Hyunyong Kim, R. Abe, M. Rozanska, H. Guler, M. Iwasaki, A.E. Bondar, H. Palka, T. Uglov, H. Sakaue, L. E. Piilonen, S. L. Olsen, G. S. Varner, B. G. Cheon, A. Ishikawa, T. Aushev, W. S. Hou, N. Soni, R. Kulasiri, A. Bay, Kazuo Abe, M. Z. Wang, K. Kinoshita, S. Saitoh, H. Yanai, Y. Asano, P. Kapusta, N. Kawamura, S. Okuno, S. K. Kim, J. Dragic, R. Itoh, Y. Mikami, E. M. Heenan, T. Mori, Makoto Tomoto, H. Park, A. Ogawa, A. Bozek, F. Fang, Tsukasa Aso, S. K. Swain, Heejong Kim, G. N. Taylor, T. Abe, R. Dowd, J. S. Kang, J. Haba, Takuya Higuchi, Antonio Limosani, S. Narita, T. Nozaki, M. Starič, Kei Suzuki, James Mueller, A. Drutskoy, Y. Teramoto, Bruce Yabsley, F. Takasaki, S. Korpar, R. Chistov, S. Y. Suzuki, Jolanta Brodzicka, Elzbieta Banas, T. Okabe, S. Banerjee, S. Kobayashi, L. Widhalm, T. E. Browder, Yuji Enari, A. Kibayashi, M. Dash, L. S. Peak, Y. Unno, K. Sumisawa, Y. Igarashi, M. Asai, L.C. Moffitt, K. Takahashi, B. Golob, K. Tanabe, K. Uchida, K. F. Chen, Y. Zheng, J. S. Lange, L. Hinz, Heyoung Yang, N. Uozaki, J. MacNaughton, M. Danilov, Byoung Sup Ahn, P. Yeh, A. Garmash, Hirokazu Ishino, T. Hokuue, K. Hara, C. C. Wang, Z. P. Zhang, B. Takeshita, A. Kuzmin, N. Katayama, Rolf Seuster, T. Matsumoto, M. Pernicka, T. Seki, Yasushi Nagasaka, S. Ogawa, I. Adachi, H. Yuta, H. Nakazawa, G. Gokhroo, M. Akatsu, A. J. Schwartz, E.A. Dodson, C.W. Everton, D. Zontar, V.N. Zhilich, S. Semenov, W. A. Mitaroff, I. Higuchi, Y. Tamai, Young-Il Choi, K. Miyabayashi, Y. B. Hsiung, Hideyuki Kawai, H. Matsumoto, T. A. Shibata, H. Miyata, M. Nakao, Prafulla Kumar Behera, N. C. Hastings, Y. Hoshi, Y. Sakai, J. Schümann, T.H. Kim, D. W. Kim, N. Kent, Y. Watanabe, J. H. Kang, H. Kichimi, Caren Hagner, T. Tsuboyama, T. Lesiak, A. Sugiyama, T. Matsuishi, G. Leder, F. Mandl, K. Tamai, M. E. Sevior, S. Matsumoto, M. Satapathy, A. Murakami, T. Ziegler, Y. Harada, M. Bračko, Sadaharu Uehara, T. Yamanaka, Samo Stanič, Shigeki Mori, A. M. Bakich, Z. Natkaniec, T. Ohshima, S.N. Tovey, Koya Abe, N. Gabyshev, You-Jin Yuan, W. Ostrowicz, C. H. Wang, C. C. Zhang, H. Shibuya, M. Watanabe, and V. Eiges

Subjects
Physics, Particle physics, KEKB, Branching fraction, Electron–positron annihilation, Pi, General Physics and Astronomy, Resonance
Abstract

We report evidence for the decay $B^0 \to \pi^0 \pi^0$. The analysis is based on a data sample of 152 million $B\bar{B}$ pairs collected at the $\Upsilon(4s)$ resonance with the Belle detector at the KEKB $e^+ e^-$ storage ring. We find $25.6^{+ 9.3}_{-8.4}(stat)^{+1.6}_{-1.4}(syst)$ $B^0 \to \pi^0 \pi^0$ signal events with a significance of 3.4 standard deviations. We measure the branching fraction to be ($1.7 \pm 0.6 (stat) \pm 0.2 (syst))*10^{-6}$.

Published
2003

41. Neutron sensitivity of the endcap RPC modules in Belle detector

Author

Y. Hoshi, T. Nagamine, K. Neichi, T. Takahashi, H. Yuta, Akira Yamaguchi, Kazuo Abe, and K. Onodera

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Muon, Meson, Physics::Instrumentation and Detectors, Detector, Belle experiment, B-factory, Nuclear physics, Nuclear Energy and Engineering, Physics::Accelerator Physics, Neutron detection, High Energy Physics::Experiment, Neutron, B meson, Electrical and Electronic Engineering
Abstract

The primary purpose in the Belle experiment at the asymmetric-energy e/sup =/e/sup -/ collider at the High-Energy Accelerator Research Organization (KEK B factory) is the measurement of charge conjugation and parity (CP) violation in B meson decays. The K/sub L/ mesons and muons (KLM) detector was designed to identify K/sub L/'s and muons in this experiment. Since October 2001, the luminosity in the KEK B accelerator has been remarkably improved. The data on B meson decay are successfully collected in the Belle detector. In contrast with the high luminosity operations of the accelerator, however, the high background rate leading to a lower detection efficiency has been observed in the endcap KLM detector. For present and future high luminosity operations, we have to identify the background source and consider the shielding. To identify the background source, the background data sampled from e/sup +/e/sup -//spl rarr//spl mu//sup +//spl mu//sup -/ events were investigated and the simulations of the sensitivity of the endcap KLM detector to neutrons and /spl gamma/'s as the background sources were performed using the Geant4 simulation toolkit. The comparisons of the simulations with the experimental data are presented.

Published
2003

42. Evidence forCP-violating asymmetries inB0→π+π−decays and constraints on the CKM angleφ2

Author

K. Abe, N. Abe, T. Abe, I. Adachi, H. Aihara, K. Akai, M. Akatsu, M. Akemoto, Y. Asano, T. Aushev, A. M. Bakich, Y. Ban, E. Banas, A. Bay, I. Bedny, P. K. Behera, I. Bizjak, A. Bondar, A. Bozek, M. Bračko, J. Brodzicka, T. E. Browder, B. C. K. Casey, P. Chang, K.-F. Chen, B. G. Cheon, R. Chistov, S.-K. Choi, Y. Choi, Y. K. Choi, M. Danilov, J. Dragic, A. Drutskoy, S. Eidelman, V. Eiges, C. W. Everton, J. Flanagan, C. Fukunaga, K. Furukawa, N. Gabyshev, A. Garmash, T. Gershon, B. Golob, R. Guo, C. Hagner, K. Hara, N. C. Hastings, K. Hasuko, H. Hayashii, M. Hazumi, T. Higuchi, L. Hinz, T. Hojo, T. Hokuue, Y. Hoshi, W.-S. Hou, Y. B. Hsiung, H.-C. Huang, T. Igaki, Y. Igarashi, T. Iijima, H. Ikeda, K. Inami, A. Ishikawa, H. Ishino, R. Itoh, H. Iwasaki, Y. Iwasaki, H. K. Jang, J. S. Kang, P. Kapusta, S. U. Kataoka, N. Katayama, G. Katano, H. Kawai, N. Kawamura, T. Kawasaki, H. Kichimi, M. Kikuchi, E. Kikutani, D. W. Kim, H. J. Kim, H. O. Kim, Hyunwoo Kim, J. H. Kim, S. K. Kim, S. Kobayashi, S. Korpar, P. Križan, P. Krokovny, T. Kubo, R. Kulasiri, S. Kumar, A. Kuzmin, Y.-J. Kwon, J. S. Lange, G. Leder, S. H. Lee, J. Li, S.-W. Lin, J. MacNaughton, F. Mandl, D. Marlow, S. Matsumoto, T. Matsumoto, S. Michizono, T. Mimashi, W. Mitaroff, K. Miyabayashi, H. Miyake, H. Miyata, G. R. Moloney, T. Mori, A. Murakami, Y. Nagasaka, T. Nakadaira, T. T. Nakamura, E. Nakano, M. Nakao, H. Nakayama, J. W. Nam, K. Neichi, S. Nishida, O. Nitoh, S. Noguchi, T. Nozaki, S. Ogawa, Y. Ogawa, K. Ohmi, Y. Ohnishi, T. Ohshima, N. Ohuchi, T. Okabe, S. Okuno, S. L. Olsen, Y. Onuki, W. Ostrowicz, H. Ozaki, H. Palka, C. W. Park, H. Park, K. S. Park, L. S. Peak, J.-P. Perroud, M. Peters, L. E. Piilonen, M. Rozanska, K. Rybicki, H. Sagawa, S. Saitoh, Y. Sakai, T. R. Sarangi, M. Satapathy, A. Satpathy, O. Schneider, S. Schrenk, J. Schümann, C. Schwanda, S. Semenov, K. Senyo, M. E. Sevior, H. Shibuya, T. Shidara, B. Shwartz, V. Sidorov, J. B. Singh, S. Stanič, M. Starič, R. Sugahara, A. Sugiyama, K. Sumisawa, T. Sumiyoshi, K. Suzuki, S. Suzuki, T. Takahashi, F. Takasaki, K. Tamai, N. Tamura, J. Tanaka, M. Tanaka, M. Tawada, G. N. Taylor, Y. Teramoto, S. Tokuda, T. Tomura, K. Trabelsi, T. Tsuboyama, T. Tsukamoto, S. Uehara, Y. Unno, S. Uno, N. Uozaki, S. E. Vahsen, G. Varner, K. E. Varvell, C. C. Wang, C. H. Wang, J. G. Wang, M.-Z. Wang, Y. Watanabe, E. Won, B. D. Yabsley, Y. Yamada, A. Yamaguchi, H. Yamamoto, Y. Yamashita, M. Yamauchi, M. Yokoyama, M. Yoshida, C. C. Zhang, Z. P. Zhang, V. Zhilich, and D. Žontar

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Electron–positron annihilation, media_common.quotation_subject, High Energy Physics::Phenomenology, Monte Carlo method, Resonance (particle physics), Asymmetry, law.invention, Nuclear physics, KEKB, law, CP violation, High Energy Physics::Experiment, B meson, Collider, media_common
Abstract

We present an improved measurement of CP-violating asymmetries in B 0→π+π- decays based on a 78 fb -1 data sample collected at the Y(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+ e- collider. We reconstruct one neutral B meson as a B0→π+π - CP eigenstate and identify the flavor of the accompanying B meson from inclusive properties of its decay products. We apply an unbinned maximum likelihood fit to the distribution of the time intervals between the two B meson decay points. The fit yields the CP-violating asymmetry amplitudes A ππ= +0.77 ±0.27(stat) ±0.08(syst) and S ππ=-1.23 ±0.41(stat) -0.07 +0.08(syst), where the statistical uncertainties are determined from the Monte Carlo pseudoexperiments. We obtain confidence intervals for CP-violating asymmetry parameters Aππ and Sππ based on a frequentist approach. We rule out the CP-conserving case, A ππ=Sππ=0, at the 99.93% confidence level. We discuss how these results constrain the value of the Cabibbo-Kobayashi-Maskawa (CKM) angle φ2. © 2003 The American Physical Society.

Published
2003

43. Studies of the DecayB±→DCPK±

Author

K. Abe, N. Abe, R. Abe, T. Abe, Byoung Sup Ahn, H. Aihara, M. Akatsu, Y. Asano, T. Aso, V. Aulchenko, T. Aushev, A. M. Bakich, Y. Ban, P. K. Behera, I. Bizjak, A. Bondar, A. Bozek, M. Bračko, T. E. Browder, B. C. K. Casey, M.-C. Chang, P. Chang, Y. Chao, B. G. Cheon, R. Chistov, Y. Choi, Y. K. Choi, M. Danilov, L. Y. Dong, A. Drutskoy, S. Eidelman, V. Eiges, Y. Enari, F. Fang, H. Fujii, C. Fukunaga, N. Gabyshev, A. Garmash, T. Gershon, B. Golob, A. Gordon, R. Guo, J. Haba, T. Hara, Y. Harada, H. Hayashii, M. Hazumi, E. M. Heenan, I. Higuchi, T. Higuchi, L. Hinz, T. Hokuue, Y. Hoshi, S. R. Hou, W.-S. Hou, S.-C. Hsu, H.-C. Huang, T. Igaki, Y. Igarashi, T. Iijima, K. Inami, A. Ishikawa, H. Ishino, R. Itoh, H. Iwasaki, Y. Iwasaki, H. K. Jang, J. H. Kang, J. S. Kang, N. Katayama, Y. Kawakami, N. Kawamura, T. Kawasaki, H. Kichimi, D. W. Kim, Heejong Kim, H. J. Kim, H. O. Kim, Hyunwoo Kim, S. K. Kim, T. H. Kim, K. Kinoshita, S. Korpar, P. Križan, P. Krokovny, R. Kulasiri, S. Kumar, A. Kuzmin, Y.-J. Kwon, J. S. Lange, G. Leder, S. H. Lee, J. Li, A. Limosani, D. Liventsev, R.-S. Lu, J. MacNaughton, G. Majumder, F. Mandl, D. Marlow, T. Matsuishi, S. Matsumoto, T. Matsumoto, W. Mitaroff, K. Miyabayashi, Y. Miyabayashi, H. Miyake, H. Miyata, G. R. Moloney, T. Mori, A. Murakami, T. Nagamine, Y. Nagasaka, T. Nakadaira, E. Nakano, M. Nakao, J. W. Nam, Z. Natkaniec, K. Neichi, S. Nishida, O. Nitoh, S. Noguchi, T. Nozaki, S. Ogawa, T. Ohshima, T. Okabe, S. Okuno, S. L. Olsen, Y. Onuki, W. Ostrowicz, H. Ozaki, P. Pakhlov, H. Palka, C. W. Park, H. Park, L. S. Peak, J.-P. Perroud, M. Peters, L. E. Piilonen, J. L. Rodriguez, F. J. Ronga, N. Root, M. Rozanska, K. Rybicki, H. Sagawa, S. Saitoh, Y. Sakai, M. Satapathy, A. Satpathy, O. Schneider, S. Schrenk, C. Schwanda, S. Semenov, K. Senyo, R. Seuster, M. E. Sevior, H. Shibuya, B. Shwartz, V. Sidorov, J. B. Singh, S. Stanič, M. Starič, A. Sugi, A. Sugiyama, K. Sumisawa, T. Sumiyoshi, K. Suzuki, S. Suzuki, S. Y. Suzuki, S. K. Swain, T. Takahashi, F. Takasaki, K. Tamai, N. Tamura, J. Tanaka, M. Tanaka, G. N. Taylor, Y. Teramoto, S. Tokuda, S. N. Tovey, K. Trabelsi, T. Tsuboyama, T. Tsukamoto, S. Uehara, K. Ueno, Y. Unno, S. Uno, Y. Ushiroda, G. Varner, K. E. Varvell, C. C. Wang, C. H. Wang, J. G. Wang, M.-Z. Wang, Y. Watanabe, E. Won, B. D. Yabsley, Y. Yamada, A. Yamaguchi, Y. Yamashita, M. Yamauchi, H. Yanai, P. Yeh, Y. Yuan, Y. Yusa, J. Zhang, Z. P. Zhang, Y. Zheng, V. Zhilich, and D. Žontar

Subjects
Physics, Particle decay, Particle physics, KEKB, Branching fraction, Electron–positron annihilation, Hadron, Analytical chemistry, Pi, General Physics and Astronomy, CP violation, B meson
Abstract

We report studies of the Cabibbo-suppressed decay B+/- --> DCPK+/-, where D-CP denotes CP eigenstates of the D-0 - (D) over bar (0) system. The analysis is based on a 29.1 fb(-1) sample collected at the Y(4S) resonance with the Belle detector at the KEKB asymmetric e(+)e(-) storage ring. We measure ratios of branching fractions, relative to Cabibbo-favored B+/--->D(CP)pi+/-, of B>(B- --> D1K-)/B(B- --> D(1)pi(-)) = 0.125 +/-0.036 +/- 0.010 and B(B- --> D2K-)/B(B- --> D(2)pi(-)) = 0.119 +/- 0.028 +/- 0.006; the index 1 (2) denotes the CP = +1 (-1) eigenstate. We also extract the partial rate asymmetries for B+/- --> DCPK+/-, finding A(1) = 0.29 +/- 0.26 +/- 0.05 and A(2) = -0.22 +/- 0.24 +/- 0.04.

Published
2003

44. Measurement of the Electroweak Penguin ProcessB→Xsℓ+ℓ−

Author

J. Kaneko, K. Abe, T. Abe, I. Adachi, Byoung Sup Ahn, H. Aihara, M. Akatsu, Y. Asano, T. Aso, V. Aulchenko, T. Aushev, A. M. Bakich, Y. Ban, E. Banas, W. Bartel, A. Bay, P. K. Behera, A. Bondar, A. Bozek, M. Bračko, J. Brodzicka, T. E. Browder, B. C. K. Casey, P. Chang, Y. Chao, K.-F. Chen, B. G. Cheon, R. Chistov, Y. Choi, Y. K. Choi, M. Danilov, L. Y. Dong, S. Eidelman, V. Eiges, Y. Enari, C. W. Everton, F. Fang, H. Fujii, C. Fukunaga, N. Gabyshev, A. Garmash, T. Gershon, R. Guo, J. Haba, F. Handa, T. Hara, Y. Harada, N. C. Hastings, H. Hayashii, M. Hazumi, E. M. Heenan, I. Higuchi, T. Higuchi, L. Hinz, T. Hojo, Y. Hoshi, W.-S. Hou, H.-C. Huang, T. Igaki, Y. Igarashi, T. Iijima, K. Inami, A. Ishikawa, H. Ishino, R. Itoh, H. Iwasaki, Y. Iwasaki, H. K. Jang, J. H. Kang, J. S. Kang, N. Katayama, H. Kawai, Y. Kawakami, N. Kawamura, T. Kawasaki, H. Kichimi, D. W. Kim, Heejong Kim, H. J. Kim, H. O. Kim, Hyunwoo Kim, S. K. Kim, K. Kinoshita, S. Kobayashi, S. Korpar, P. Križan, P. Krokovny, R. Kulasiri, S. Kumar, Y.-J. Kwon, J. S. Lange, G. Leder, S. H. Lee, J. Li, A. Limosani, R.-S. Lu, J. MacNaughton, G. Majumder, F. Mandl, D. Marlow, S. Matsumoto, T. Matsumoto, W. Mitaroff, K. Miyabayashi, Y. Miyabayashi, H. Miyake, G. R. Moloney, T. Mori, T. Nagamine, Y. Nagasaka, T. Nakadaira, E. Nakano, M. Nakao, J. W. Nam, K. Neichi, S. Nishida, O. Nitoh, S. Noguchi, T. Nozaki, S. Ogawa, T. Ohshima, T. Okabe, S. Okuno, S. L. Olsen, Y. Onuki, W. Ostrowicz, H. Ozaki, P. Pakhlov, H. Palka, C. W. Park, H. Park, K. S. Park, J.-P. Perroud, M. Peters, L. E. Piilonen, N. Root, K. Rybicki, H. Sagawa, Y. Sakai, H. Sakamoto, M. Satapathy, A. Satpathy, O. Schneider, S. Schrenk, C. Schwanda, S. Semenov, K. Senyo, R. Seuster, H. Shibuya, B. Shwartz, V. Sidorov, J. B. Singh, N. Soni, S. Stanič, K. Sumisawa, T. Sumiyoshi, K. Suzuki, S. Suzuki, S. Y. Suzuki, S. K. Swain, H. Tajima, T. Takahashi, F. Takasaki, K. Tamai, N. Tamura, J. Tanaka, M. Tanaka, G. N. Taylor, Y. Teramoto, S. Tokuda, M. Tomoto, T. Tomura, K. Trabelsi, W. Trischuk, T. Tsuboyama, T. Tsukamoto, S. Uehara, K. Ueno, S. Uno, Y. Ushiroda, G. Varner, K. E. Varvell, C. C. Wang, C. H. Wang, J. G. Wang, M.-Z. Wang, Y. Watanabe, E. Won, B. D. Yabsley, Y. Yamada, A. Yamaguchi, Y. Yamashita, M. Yamauchi, H. Yanai, J. Yashima, M. Yokoyama, Y. Yuan, Y. Yusa, C. C. Zhang, J. Zhang, Z. P. Zhang, Y. Zheng, V. Zhilich, and D. Žontar

Subjects
Physics, Particle physics, Strange quark, Muon, Branching fraction, Electron–positron annihilation, Hadron, Electroweak interaction, General Physics and Astronomy, Nuclear physics, KEKB, High Energy Physics::Experiment, B meson, Nuclear Experiment
Abstract

We report the first measurement of the branching fraction for the inclusive decay B → X s l + l - , where l is either an electron or a muon, and X s is a hadronic recoil system that contains an s quark. We analyzed a data sample of 65.4 x 10 6 B meson pairs collected with the Belle detector at the KEKB e + e - asymmetric-energy collider. We find B(B → X s l + l - ) = [6.1 ′ 1.4(stat) + 1 . 4 - 1 . 1 (syst)] × 10 - 6 for dilepton masses greater than 0.2 GeV/c 2 .

Published
2003

45. Free ion yields for tetramethylsilane and tetramethylgermanium

Author

K. Neichi, Kazuo Hasegawa, K. Masuda, H. Yuta, Ryusaburo Kikuchi, K. Suzuki, Masato Higuchi, Y. Hoshi, H. Iso, M. Sakamoto, Koji Abe, N. Kawamura, Kazumasa Miyano, F. Suekane, and K. Oyama

Subjects
chemistry.chemical_compound, Thermalisation, Materials science, chemistry, Impurity, Electric field, Ionization, Analytical chemistry, Electron, Dielectric, Tetramethylsilane, Ion
Abstract

The free ion yields from /sup 207/Bi conversion electrons were measured as a function of applied electric field using ionization chambers filled with tetramethylsilane (TMS) and tetramethylgermanium (TMG). The distributions for thermalization lengths of electrons were calculated by using Gaussian and exponential forms. The total free ion yields considering the impurity effect in liquid, and the thermalization lengths of electrons in TMS and TMG were determined to be 3.35+or-0.49, 3.42+or-0.56 and 165+or-18 AA, 185+or-24 AA, respectively. >

Published
2003

46. Radiation damage to tetramethlysilane and tetramethlygermanium ionization chambers

Author

K. Neichi, K. Hasegawa, H. Akaishi, K. Miyano, Y. Hoshi, K. Masuda, R. Kikuchi, T. Nagamine, J. Katayama, Masato Higuchi, K. Abe, K. Oyama, T. Nakajima, N. Kawamura, F. Suekane, and H. Yuta

Subjects
Nuclear and High Energy Physics, Dosimeter, Materials science, Analytical chemistry, Particle detector, Ion, Nuclear physics, chemistry.chemical_compound, Nuclear Energy and Engineering, chemistry, Ionization, Ionization chamber, Radiation damage, Electrical and Electronic Engineering, Cobalt-60, Tetramethylsilane
Abstract

Two detector media suitable for a warm liquid ionization chamber filled with tetramethylsilane (TMS) and tetramethylgermanium (TMG) were exposed to /spl gamma/-radiation from a /sup 60/Co source up to a dose of 579 Gray and 902 Gray, respectively. The electron lifetimes and the free ion yields were measured as a function of accumulated radiation dose. A similar behavior of the electron lifetimes and the free ion yields with increasing radiation dose was observed between the TMS and TMG ionization chambers. >

Published
1994

47. Observation ofDs+K−and Evidence forDs+π−Final States in NeutralBDecays

Author

P. Krokovny, K. Abe, T. Abe, I. Adachi, Byoung Sup Ahn, H. Aihara, M. Akatsu, Y. Asano, T. Aso, V. Aulchenko, T. Aushev, A. M. Bakich, Y. Ban, E. Banas, A. Bay, I. Bedny, P. K. Behera, I. Bizjak, A. Bondar, A. Bozek, M. Bračko, J. Brodzicka, T. E. Browder, B. C. K. Casey, P. Chang, Y. Chao, K.-F. Chen, B. G. Cheon, R. Chistov, S.-K. Choi, Y. Choi, M. Danilov, L. Y. Dong, A. Drutskoy, S. Eidelman, V. Eiges, Y. Enari, C. W. Everton, F. Fang, C. Fukunaga, N. Gabyshev, A. Garmash, T. Gershon, B. Golob, A. Gordon, R. Guo, J. Haba, K. Hanagaki, F. Handa, Y. Harada, H. Hayashii, M. Hazumi, E. M. Heenan, T. Higuchi, L. Hinz, T. Hojo, T. Hokuue, Y. Hoshi, W.-S. Hou, H.-C. Huang, T. Igaki, T. Iijima, K. Inami, A. Ishikawa, H. Ishino, R. Itoh, H. Iwasaki, H. K. Jang, J. Kaneko, J. H. Kang, J. S. Kang, N. Katayama, H. Kawai, Y. Kawakami, N. Kawamura, T. Kawasaki, H. Kichimi, D. W. Kim, Heejong Kim, H. J. Kim, H. O. Kim, Hyunwoo Kim, S. K. Kim, K. Kinoshita, S. Kobayashi, S. Korpar, P. Križan, R. Kulasiri, S. Kumar, A. Kuzmin, Y.-J. Kwon, J. S. Lange, G. Leder, S. H. Lee, J. Li, A. Limosani, D. Liventsev, R.-S. Lu, J. MacNaughton, G. Majumder, F. Mandl, D. Marlow, T. Matsuishi, S. Matsumoto, T. Matsumoto, W. Mitaroff, K. Miyabayashi, Y. Miyabayashi, H. Miyake, H. Miyata, G. R. Moloney, T. Mori, A. Murakami, T. Nagamine, Y. Nagasaka, T. Nakadaira, E. Nakano, M. Nakao, H. Nakazawa, J. W. Nam, Z. Natkaniec, K. Neichi, S. Nishida, O. Nitoh, T. Nozaki, S. Ogawa, T. Ohshima, T. Okabe, S. L. Olsen, Y. Onuki, W. Ostrowicz, H. Ozaki, P. Pakhlov, C. W. Park, H. Park, J.-P. Perroud, M. Peters, L. E. Piilonen, F. J. Ronga, N. Root, K. Rybicki, H. Sagawa, S. Saitoh, Y. Sakai, H. Sakamoto, M. Satapathy, A. Satpathy, O. Schneider, C. Schwanda, S. Semenov, K. Senyo, H. Shibuya, B. Shwartz, V. Sidorov, J. B. Singh, S. Stanič, M. Starič, A. Sugi, A. Sugiyama, K. Sumisawa, T. Sumiyoshi, K. Suzuki, S. Suzuki, S. Y. Suzuki, S. K. Swain, T. Takahashi, F. Takasaki, K. Tamai, N. Tamura, J. Tanaka, M. Tanaka, G. N. Taylor, Y. Teramoto, S. Tokuda, T. Tomura, K. Trabelsi, T. Tsuboyama, T. Tsukamoto, S. Uehara, K. Ueno, Y. Unno, S. Uno, Y. Ushiroda, G. Varner, K. E. Varvell, C. C. Wang, C. H. Wang, J. G. Wang, M.-Z. Wang, Y. Watanabe, E. Won, B. D. Yabsley, Y. Yamada, A. Yamaguchi, Y. Yamashita, M. Yamauchi, H. Yanai, J. Yashima, Y. Yuan, Y. Yusa, C. C. Zhang, J. Zhang, Z. P. Zhang, Y. Zheng, V. Zhilich, and D. Žontar

Subjects
Physics, Nuclear magnetic resonance, KEKB, Annihilation, Branching fraction, Electron–positron annihilation, Pi, Analytical chemistry, General Physics and Astronomy, Value (computer science), B meson
Abstract

We report the first observation of a B meson decay that is not accessible by a direct spectator process. The channel B(0)-->D(+)(s)K- is found in a sample of 85 x 10(6) BB; events, collected with the Belle detector at KEKB, with a branching fraction B(B(0)-->D(+)(s)K-)=(4.6(+1.2)(-1.1)+/-1.3) x 10(-5). We also obtain evidence for the B0-->D(+)(s)pi(-) decay with branching fraction B(B0-->D(+)(s)pi(-))=(2.4(+1.0)(-0.8)+/-0.7) x 10(-5). This value may be used to extract a model-dependent value of |V(ub)|.

Published
2002

48. RadiativeBMeson Decays intoKπγandKππγFinal States

Author

S. Nishida, M. Nakao, K. Abe, T. Abe, Byoung Sup Ahn, H. Aihara, M. Akatsu, Y. Asano, T. Aushev, A. M. Bakich, Y. Ban, E. Banas, W. Bartel, A. Bay, I. Bedny, A. Bondar, A. Bozek, M. Bračko, J. Brodzicka, T. E. Browder, B. C. K. Casey, P. Chang, Y. Chao, B. G. Cheon, R. Chistov, S.-K. Choi, Y. Choi, M. Danilov, L. Y. Dong, A. Drutskoy, S. Eidelman, V. Eiges, Y. Enari, C. Fukunaga, N. Gabyshev, T. Gershon, A. Gordon, K. Gotow, R. Guo, J. Haba, T. Hara, H. Hayashii, M. Hazumi, E. M. Heenan, I. Higuchi, T. Higuchi, T. Hojo, T. Hokuue, Y. Hoshi, S. R. Hou, W.-S. Hou, S.-C. Hsu, H.-C. Huang, T. Igaki, T. Iijima, K. Inami, A. Ishikawa, H. Ishino, R. Itoh, M. Iwamoto, H. Iwasaki, Y. Iwasaki, P. Jalocha, H. K. Jang, J. H. Kang, P. Kapusta, S. U. Kataoka, N. Katayama, H. Kawai, Y. Kawakami, N. Kawamura, T. Kawasaki, H. Kichimi, D. W. Kim, Heejong Kim, H. J. Kim, H. O. Kim, Hyunwoo Kim, T. H. Kim, K. Kinoshita, P. Križan, P. Krokovny, R. Kulasiri, S. Kumar, Y.-J. Kwon, J. S. Lange, G. Leder, S. H. Lee, J. Li, R.-S. Lu, J. MacNaughton, G. Majumder, F. Mandl, S. Matsumoto, T. Matsumoto, Y. Mikami, W. Mitaroff, K. Miyabayashi, H. Miyake, H. Miyata, G. R. Moloney, S. Mori, T. Nagamine, Y. Nagasaka, T. Nakadaira, E. Nakano, J. W. Nam, Z. Natkaniec, K. Neichi, O. Nitoh, S. Noguchi, T. Nozaki, S. Ogawa, F. Ohno, T. Ohshima, T. Okabe, S. Okuno, S. L. Olsen, W. Ostrowicz, H. Ozaki, P. Pakhlov, H. Palka, C. W. Park, H. Park, K. S. Park, L. S. Peak, J.-P. Perroud, M. Peters, L. E. Piilonen, M. Rozanska, K. Rybicki, H. Sagawa, S. Saitoh, Y. Sakai, H. Sakamoto, M. Satapathy, A. Satpathy, O. Schneider, S. Schrenk, C. Schwanda, S. Semenov, K. Senyo, R. Seuster, M. E. Sevior, H. Shibuya, B. Shwartz, V. Sidorov, J. B. Singh, S. Stanič, A. Sugi, A. Sugiyama, K. Sumisawa, T. Sumiyoshi, K. Suzuki, S. Suzuki, T. Takahashi, F. Takasaki, K. Tamai, N. Tamura, M. Tanaka, G. N. Taylor, Y. Teramoto, S. Tokuda, M. Tomoto, T. Tomura, S. N. Tovey, K. Trabelsi, T. Tsuboyama, T. Tsukamoto, S. Uehara, K. Ueno, S. Uno, Y. Ushiroda, G. Varner, K. E. Varvell, C. C. Wang, C. H. Wang, J. G. Wang, M.-Z. Wang, Y. Watanabe, E. Won, B. D. Yabsley, Y. Yamada, A. Yamaguchi, H. Yamamoto, Y. Yamashita, M. Yamauchi, Y. Yuan, Y. Yusa, J. Zhang, Z. P. Zhang, V. Zhilich, and D. Žontar

Subjects
Physics, General Physics and Astronomy
Published
2002

49. A search for freonless gas mixture for glass RPC

Author

S. Narita, K. Watanabe, K. Abe, F. Handa, I. Higuchi, Y. Hoshi, N. Kawamura, K. Kumagai, Y. Mikami, N. Murono, T. Nagamine, K. Neichi, T. Takahashi, M. Yamaga, A. Yamaguchi, Y. Yusa, and H. Yuta

Published
2002

50. Study of streamer size measurements using CCD camera system

Author

N. Murono, T. Nagamine, K. Watanabe, K. Neichi, Koji Abe, K. Higuchi, T. Kawamura, Y. Teramoto, Akira Yamaguchi, H. Mikami, H. Yuta, N. Takahashi, Y. Hoshi, S. Handa, K. Kumagai, M. Yamaga, Y. Yusa, and S. Narita

Subjects
Physics, Argon, Ccd camera, business.industry, Image intensifier, chemistry.chemical_element, law.invention, Pulse (physics), Optics, chemistry, law, Mixing ratio, Pickup, Oscilloscope, business, Intensity (heat transfer)
Abstract

We report on a study of correlation between readout pulses and lights of streamer produced in the glass resistive plate chamber (RPC) with six Ar gas mixtures (Ar/butane-silver/HFC134a). The streamer pulse produced by cosmic-ray are analyzed as a function of Ar/HFC134a mixing ratio using a digital oscilloscope. The streamer image due to the lights from the streamer is taken by using an image intensifier and a CCD camera. The average streamer size become larger linearly with increase Ar gas mixing ratio. The Ar/HFC134a ratio dependence of the charge and intensity were studied. The analysis of the light image of streamer might be useful for us to design the pickup pad width for the readout.

Published
2002

Catalog

Books, media, physical & digital resources
See catalog results