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881.
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R. Henn H. von Falkenhausen W. Kern M. Müller S. Stöppler K. Bohr F. Ferschl H. J. Jaksch K. Kirchgässner H. -H. Bock W. R. Bihn H. Sabel H. Schneeweiss G. Menges 《Mathematical Methods of Operations Research》1968,12(1):281-296
Ohne Zusammenfassung 相似文献
884.
885.
Alavi-Harati A Albuquerque IF Alexopoulos T Arenton M Arisaka K Averitte S Barker AR Bellantoni L Bellavance A Belz J Ben-David R Bergman DR Blucher E Bock GJ Bown C Bright S Cheu E Childress S Coleman R Corcoran MD Corti G Cox B Crisler MB Erwin AR Ford R Glazov A 《Physical review letters》2000,84(3):408-411
We report the first observation of a manifestly CP violating effect in the K(L)-->pi(+)pi(-)e(+)e(-) decay mode. A large asymmetry was observed in the distribution of these decays in the CP-odd and T-odd angle straight phi between the decay planes of the e(+)e(-) and pi(+)pi(-) pairs in the K(L) center of mass system. After acceptance corrections, the overall asymmetry is found to be [13.6+/-2. 5(stat)+/-1.2(syst)]%. This is the largest CP-violating effect yet observed when integrating over the entire phase space of a mode and the first such effect observed in an angular variable. 相似文献
886.
Alavi-Harati A Alexopoulos T Arenton M Arisaka K Averitte S Barker AR Bellantoni L Bellavance A Belz J Ben-David R Bergman DR Blucher E Bock GJ Bown C Bright S Cheu E Childress S Coleman R Corcoran MD Corti G Cox B Crisler MB Erwin AR Ford R Glazov A Golossanov A 《Physical review letters》2000,84(12):2593-2597
We present results of a search for a new form of hadronic matter, a six-quark, dibaryon state called the H0, a state predicted to exist in several theoretical models. Analyzing data collected by experiment E799-II at Fermilab, we searched for the decay H0-->Lambdappi(-) and found no candidate events. We place an upper limit on [B(H0-->Lambdappi(-))dsigma(H)/dOmega]/(dsigma(Xi)/dOmega) and, in the context of published models, exclude the region of lightly bound mass states just below the LambdaLambda mass threshold, 2.194相似文献
887.
Aggarwal MM Agnihotri A Ahammed Z Angelis AL Antonenko V Arefiev V Astakhov V Avdeitchikov V Awes TC Baba PV Badyal SK Barlag C Bathe S Batiounia B Bernier T Bhalla KB Bhatia VS Blume C Bock R Bohne EM Böröcz Z Bucher D Buijs A Büsching H Carlen L Chalyshev V Chattopadhyay S Cherbatchev R Chujo T Claussen A Das AC Decowski MP Delagrange H Djordjadze V Donni P Doubovik I Dutt S Dutta Majumdar MR El Chenawi K Eliseev S Enosawa K Foka P Fokin S Ganti MS Garpman S Gavrishchuk O Geurts FJ Ghosh TK 《Physical review letters》2000,85(14):2895-2899
Three-particle correlations have been measured for identified pi(-) from central 158A GeV Pb+Pb collisions by the WA98 experiment at CERN. A substantial contribution of the genuine three-body correlation has been found as expected for a mainly chaotic and symmetric source. 相似文献
888.
Jaffe AH Ade PA Balbi A Bock JJ Bond JR Borrill J Boscaleri A Coble K Crill BP de Bernardis P Farese P Ferreira PG Ganga K Giacometti M Hanany S Hivon E Hristov VV Iacoangeli A Lange AE Lee AT Martinis L Masi S Mauskopf PD Melchiorri A Montroy T Netterfield CB Oh S Pascale E Piacentini F Pogosyan D Prunet S Rabii B Rao S Richards PL Romeo G Ruhl JE Scaramuzzi F Sforna D Smoot GF Stompor R Winant CD Wu JH 《Physical review letters》2001,86(16):3475-3479
Recent results from BOOMERANG-98 and MAXIMA-1, taken together with COBE DMR, provide consistent and high signal-to-noise measurements of the cosmic microwave background power spectrum at spherical harmonic multipole bands over 2相似文献
889.
Alavi-Harati A Alexopoulos T Arenton M Arisaka K Averitte S Barker AR Bellantoni L Bellavance A Belz J Ben-David R Bergman DR Blucher E Bock GJ Bown C Bright S Cheu E Childress S Coleman R Corcoran MD Corti G Cox B Crisler MB Erwin AR Ford R Glazov A Golossanov A Graham G Graham J Hagan K Halkiadakis E Hamm J Hanagaki K Hidaka S Hsiung YB Jejer V Jensen DA Kessler R Kobrak HG LaDue J Lath A Ledovskoy A McBride PL Mikelsons P Monnier E Nakaya T Nelson KS Nguyen H O'Dell V Pang M Pordes R 《Physical review letters》2001,86(15):3239-3243
We have studied the rare weak radiative hyperon decay Xi degrees -->Sigma degrees gamma in the KTeV experiment at Fermilab. We have identified 4045 signal events over a background of 804 events. The dominant Xi degrees -->Lambdapi degrees decay, which was used for normalization, is the only important background source. An analysis of the acceptance of both modes yields a branching ratio of B(Xi degrees -->Sigma degrees gamma)/B(Xi degrees -->Lambdapi degrees ) = (3.34+/-0.05+/-0.09)x10(-3). By analyzing the final state decay distributions, we have also determined that the Sigma degrees emission asymmetry parameter for this decay is alpha(XiSigma) = -0.63+/-0.09. 相似文献
890.
UV-A breakage sensitivity of human chromosomes as measured by COMET-FISH depends on gene density and not on the chromosome size 总被引:5,自引:0,他引:5
Rapp A Bock C Dittmar H Greulich KO 《Journal of photochemistry and photobiology. B, Biology》2000,56(2-3):109-117
COMET-FISH, a single cell-based combination of COMET-assay (also known as single cell gel electrophoresis (SCGE)) with fluorescence in situ hybridization (FISH) allows region specific studies on DNA stability and damage. COMET-FISH can be used to investigate UV-A-induced DNA damage of selected whole chromosomes. In the present work, a modified COMET-FISH protocol with whole chromosome painting probes was used to study whether UV-A-induced DNA damage is distributed randomly over the whole genome or occurs at preferred sites. The study was performed with 12 different chromosome painting probes (for chromosomes 1, 2, 3, 8, 9, 11, 14, 18, 19, 21, X and Y). The results on human lymphocytes irradiated with 500 kJ/m2 at a wavelength of 365 nm indicate that the induced number of chromatin strand breaks does not correlate with the chromosome size. They therefore are distributed in a non-random manner. For example, fragments of the gene-rich chromosome chromosome 1 were found in the comet tail in only 3% of the examined cells, and thus chromosome 1 is rather stable, whereas fragmentation of the gene-poor chromosome 8 was observed in 25% of all comets. On the basis of all 12 chromosomes analyzed, an inverse correlation between the density of active genes and the sensitivity toward UV-A radiation is found. 相似文献