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91.
R. E. Ansorge B. ?sman C. N. Booth L. Burow P. Carlson R. S. De Wolf B. Eckart G. Ekspong C. Fuglesang J. Gaudaen C. Geich-Gimbel B. Holl R. Hospes K. Jon-And D. P. Johnson F. Lotse N. Manthos D. J. Munday J. E. V. Ovens W. Pelzer J. G. Rushbrooke F. Triantis L. Van hamme C. Walck C. P. Ward D. R. Ward C. J. S. Webber T. O. White G. Wilquet N. Yamdagni UA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1988,41(2):179-190
A detailed analysis ofK s 0 production in \(\bar pp\) |<2.5 the average transverse momentum is found to be 0.53±0.07 GeV/c at 200 GeV and 0.62±0.08 GeV/c at 900 GeV, which is an increase with respect to data at c.m. energies below 60 GeV. TheK s 0 production cross sections in inelastic collisions are 29±4 mb at 200 GeV and 63±6 mb at 900 GeV, showing an increase compared to lower energy data. The central kaon density is found to increase as a logarithmic function of energy. At 900 GeV, where statistics are sufficient to allow one to draw conclusions, the average transverse momentum is higher in events with large charged multiplicity than in events with low multiplicity. 相似文献
92.
Wong KL Bitter M Hammett GW Heidbrink W Hendel H Kaita R Scott S Strachan JD Tait G Bell MG Budny R Bush C Chan A Coonrod J Efthimion PC England AC Eubank HP Fredrickson E Furth HP Goldston RJ Grek B Grisham L Hawryluk RJ Hill KW Johnson D Kamperschroer J Kugel H Ma C Mansfield D Manos D McCune DC McGuire K Medley SS Mueller D Nieschmidt E Owens DK Paré VK Park H Ramsey A Rasmussen D Roquemore AL Schivell J Sesnic S Taylor G Williams MD Zarnstorff MC 《Physical review letters》1985,55(23):2587-2590
93.
94.
Using a triple plasma device, strong double layers (Δ 20 Te/e) have been produced in an axial magnetic field of 50 G. Numerical results indicate that suppression of plasma generation in the region of a double layer is necessary for its existence. 相似文献
95.
Fernandez E Ford WT Qi N Read AL Smith JG Camporesi T De Sangro R Marini A Peruzzi I Piccolo M Ronga F Blume HT Hurst RB Venuti JP Wald HB Weinstein R Band HR Gettner MW Goderre GP Meyer OA Moromisato JH Shambroom WD Sleeman JC von Goeler E Ash WW Chadwick GB Clearwater SH Coombes RW Kaye HS Lau KH Leedy RE Lynch HL Messner RL Moss LJ Muller F Nelson HN Ritson DM Rosenberg LJ Wiser DE Zdarko RW Groom DE Lee H Delfino MC Heltsley BK Johnson JR Lavine TL Maruyama T Prepost R 《Physical review letters》1985,54(15):1620-1623
96.
Ash WW Band HR Blume HT Camporesi T Chadwick GB Coombes RW Delfino MC Fernandez E Ford WT Gettner MW Goderre GP Groom DE Heltsley BK Hurst RB Johnson JR Lau KH Lavine TL Leedy RE Lippi I Maruyama T Messner RL Moromisato JH Moss LJ Muller F Nelson HN Peruzzi I Piccolo M Prepost R Qi N Read AL Ritson DM Rosenberg LJ Shambroom WD Sleeman JC Smith JG Venuti JP von Goeler E Verdini P Wald HB Weinstein R Wiser DE Zdarko RW 《Physical review letters》1985,55(20):2118-2121
97.
Johnson TA Neely ST Kopun JG Gorga MP 《The Journal of the Acoustical Society of America》2006,119(6):3896-3907
Distortion product otoacoustic emission (DPOAE) fine structure has been attributed to the interaction of two cochlear-source mechanisms (distortion and reflection sources). A suppressor presented near the 2f1-f2 frequency reduces the reflection-source contribution and, therefore, DPOAE fine structure. Optimal relationships between stimulus and suppressor conditions, however, have not been described. In this study, the relationship between suppressor level (L3) and stimulus level (L2) was evaluated to determine the L3 that was most effective at reducing fine structure. Subjects were initially screened to find individuals who produced DPOAE fine structure. A difference in the prevalence of fine structure in two frequency intervals was observed. At 2 kHz, 11 of 12 subjects exhibited fine structure, as compared to 5 of 22 subjects at 4 kHz. Only subjects demonstrating fine structure participated in subsequent measurements. DPOAE responses were evaluated in 1/3-octave intervals centered at 2 or 4 kHz, with 4 subjects contributing data at each interval. Multiple L3's were evaluated for each L2, which ranged from 20 to 80 dB SPL. The results indicated that one or more L3's at each L2 were roughly equally effective at reducing DPOAE fine structure. However, no single L3 was effective at all L2's in every subject. 相似文献
98.
What implications do the ranges of traditional and non-traditional media used by contemporary artists have for understanding the selection and specification of coloured materials? Interviews with prominent artists explore their use of colour and their views on the role of colour in their work. The paper establishes that the interview respondents operate successfully within a professional and permeable frame of reference, with different approaches to determination of colour meaning. The colour propositions of neuroscience, psychophysics and anthropological linguistics appear to have little impact on the respondents’ practice, and the paper concludes by suggesting the need to explore boundaries between disciplines. 相似文献
99.
J.R. Petta A.C. Johnson J.M. Taylor E.A. Laird A. Yacoby M.D. Lukin C.M. Marcus M.P. Hanson A.C. Gossard 《Physica E: Low-dimensional Systems and Nanostructures》2006,35(2):251
We use gate voltage control of the exchange interaction to prepare, manipulate, and measure two-electron spin states in a GaAs double quantum dot. By placing two electrons in a single dot at low temperatures we prepare the system in a spin singlet state. The spin singlet is spatially separated by transferring an electron to an adjacent dot. The spatially separated spin singlet state dephases in due to the contact hyperfine interaction with the GaAs host nuclei. To combat the hyperfine dephasing, we develop quantum control techniques based on fast electrical control of the exchange interaction. We demonstrate coherent spin-state rotations in a singlet–triplet qubit and harness the coherent rotations to implement a singlet–triplet spin echo refocusing pulse sequence. The singlet–triplet spin echo extends the spin coherence time to . 相似文献
100.
Abe K Abe K Abe T Adam I Akimoto H Aston D Baird KG Baltay C Band HR Barklow TL Bauer JM Bellodi G Berger R Blaylock G Bogart JR Bower GR Brau JE Breidenbach M Bugg WM Burke D Burnett TH Burrows PN Calcaterra A Cassell R Chou A Cohn HO Coller JA Convery MR Cook V Cowan RF Crawford G Damerell CJ Daoudi M de Groot N de Sangro R Dong DN Doser M Dubois R Erofeeva I Eschenburg V Fahey S Falciai D Fernandez JP Flood K Frey R Hart EL Hasuko K Hertzbach SS Huffer ME Huynh X Iwasaki M Jackson DJ 《Physical review letters》2003,90(14):141804
We present an improved direct measurement of the parity-violation parameter A(b) in the Z boson-b-quark coupling using a self-calibrating track-charge technique applied to a sample enriched in Z-->bb events via the topological reconstruction of the B hadron mass. Manipulation of the Stanford Linear Collider electron-beam polarization permits the measurement of A(b) to be made independently of other Z-pole coupling parameters. From the 1996-1998 sample of 400,000 hadronic Z decays, produced with an average beam polarization of 73.4%, we find A(b)=0.906+/-0.022(stat)+/-0.023(syst). 相似文献