共查询到20条相似文献,搜索用时 31 毫秒
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Partial wave analysis of the reactions $p\bar p \to \pi \pi ,\eta \eta ,\eta \eta '$ in the region of invariant masses 1900–2400 MeV indicates the existence of four relatively narrow tensor-isoscalar resonances ? 2(1920), ? 2(2020), ? 2(2240), ? 2(2300), as well as the broad state ? 2(2000). The determined decay couplings of the broad resonance ? 2(2000) → π0π0, ηη, ηη′ satisfy the relations appropriate to those of a tensor glueball, while the couplings of other tensor states do not, thus verifying the glueball nature of ? 2(2000). 相似文献
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Aihara H Alston-Garnjost M Avery RE Barbaro-Galtieri A Barker AR Barnett BA Bauer DA Bay A Bobbink GJ Buchanan CD Buijs A Caldwell DO Chao HY Chun SB Clark AR Cowan GD Crane DA Dahl OI Daoudi M Derby KA Eastman JJ Eberhard PH Edberg TK Eisner AM Erné FC Fairfield KH Hauptman JM Hofmann W Hylen J Kamae T Kaye HS Kenney RW Khacheryan S Kofler RR Langeveld WG Layter JG Lin WT Linde FL Loken SC Lu A Lynch GR Madaras RJ Magnuson BD Masek GE Mathis LG Matthews JA Maxfield SJ Miller ES Moses W 《Physical review letters》1990,64(2):172-175
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Daoudi M Ford WT Johnson DR Lingel K Lohner M Rankin P Smith JG Alexander J Bebek C Berkelman K Besson D Browder TE Cassel DG Cheu E Coffman DM Drell PS Ehrlich R Galik RS Garcia-Sciveres M Geiser B Gittelman B Gray SW Hartill DL Heltsley BK Honscheid K Kandaswamy J Katayama N Kim PC Kreinick DL Lewis JD Ludwig GS Masui J Mevissen J Mistry NB Nandi S Ng CR Nordberg E O'Grady C Patterson JR Peterson D Pisharody M Riley D Sapper M Selen M Worden H Worris M Avery P Freyberger A Rodriguez J 《Physical review D: Particles and fields》1992,45(11):3965-3975
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John Lott 《Communications in Mathematical Physics》1984,93(4):533-558
The vacuum charge of a second quantized spinor field in a static classical background field on a static spacetime is studied. Wheng
00=1 the vacuum charge is shown to be essentially the eta function of the spinor Hamiltonian ats=0. This is computed for compact and noncompact spaces and a boundary dependence is derived in the latter case. 相似文献
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Richichi SJ Severini H Skubic P Undrus A Chen S Fast J Hinson JW Lee J Menon N Miller DH Shibata EI Shipsey IP Pavlunin V Cronin-Hennessey D Kwon Y Lyon AL Thorndike EH Jessop CP Marsiske H Perl ML Savinov V Ugolini D Zhou X Coan TE Fadeyev V Maravin Y Narsky I Stroynowski R Ye J Wlodek T Artuso M Ayad R Boulahouache C Bukin K Dambasuren E Karamnov S Kopp S Majumder G Moneti GC Mountain R Schuh S Skwarnicki T Stone S Viehauser G Wang JC Wolf A Wu J Csorna SE Danko I Zhou GJ 《Physical review letters》2000,85(3):520-524
In a sample of 19 x 10(6) produced B mesons, we have observed the decays B-->eta K(*) and improved our previous measurements of B-->eta'K. The branching fractions we measure for these decay modes are B(B+-->eta K(*+)) = (26.4(+9.6)(-8.2)+/-3.3)x10(-6), B(B(0)-->eta K(*0)) = (13.8(+5.5)(-4.6)+/-1.6)x10(-6), B(B(+)-->eta'K(+) = (80(+10)(-9)+/-7)x10(-6), and B(B(0)-->eta'K0) = (89(+18)(-16)+/-9)x10(-6). We have searched with comparable sensitivity for related decays and report upper limits for these branching fractions. 相似文献
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Georgi H 《Physical review D: Particles and fields》1994,49(3):1666-1667
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White DB Tippens WB Abegg R Baldisseri A Boudard A Briscoe W Fabbro B Garçon M Hermes EA Jacobs WW Kessler RS Lytkin L Mayer B Nefkens BM Niebuhr C Petrov AM Poitou J Saudinos J Tomasi-Gustafsson E van der Schaaf A van Oers WT Vigdor SE Wang M 《Physical review D: Particles and fields》1996,53(11):6658-6661
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Wormser G Abrams G Amidei D Baden AR Barklow T Boyarski AM Boyer J Burchat PR Burke DL Butler F Dorfan JM Feldman GJ Gidal G Gladney L Gold MS Goldhaber G Golding L Haggerty J Hanson G Hayes K Herrup D Hollebeek RJ Innes WR Jaros JA Juricic I Kadyk JA Karlen D Klein SR Lankford AJ Larsen RR LeClaire BW Levi M Lockyer NS Lüth V Nelson ME Ong RA Perl ML Richter B Riles K Rowson PC Schaad T Schellman H Schmidke WB Sheldon PD Trilling GH Wood DR Yelton JM 《Physical review letters》1988,61(9):1057-1060
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M.R. Jane P. Grannis B.D. Jones N.H. Lipman D.P. Owen V.Z. Peterson W.T. Toner E.H. Bellamy M.G. Green J. Kirkby C. Solomonides J.A. Strong D.H. Thomas 《Physics letters. [Part B]》1975,59(1):103-105
In an optical spark chamber experiment we have obtained a sample of 80 eta Dalitz decays (η → e+e?γ) and have measured the eta electromagnetic form factor to be F(X) = 1.0?(0.22 ±0.45)X, where X=Mee2/Mη2, and the branching ratio (η→e+e?γ/(η→π+π?π0)= (0.0082 ± 0.0020). 相似文献
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Czyzykiewicz R Moskal P Adam HH Budzanowski A Czerwiński E Gil D Grzonka D Hodana M Janusz M Jarczyk L Kamys B Khoukaz A Kilian K Klaja P Lorentz B Oelert W Piskor-Ignatowicz C Przerwa J Rejdych B Ritman J Sefzick T Siemaszko M Smyrski J Täschner A Ulbrich K Winter P Wolke M Wüstner P Zipper W 《Physical review letters》2007,98(12):122003
Measurements of the analyzing power for the pp-->pp eta reaction have been performed at excess energies of Q=10 and 36 MeV. The determined analyzing power is essentially consistent with zero, implying dominance of the s wave at both excess energies. The angular dependence of the analyzing power, combined with the isospin dependence of the total cross section for the eta meson production in nucleon-nucleon collisions, reveal that the excitation of the nucleon to the S11(1535) resonance is predominantly due to the exchange of the pi meson between the colliding nucleons. 相似文献
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S. Della Pietra V. Della Pietra L. Alvarez-Gaumé 《Communications in Mathematical Physics》1987,109(4):691-700
For {
y
},y, a one parameter family of invertible Weyl operators of possibly non-zero index acting on spinors over an even dimensional compact manifoldX, we express the phase of the chiral determinant det
–
in terms of the invariant of a Dirac operator acting on spinors over ×X.Supported in part by NSF Grant No. PHY-82-15249Supported in part by NSF Grant PHY 8605978 and the Robert A. Welch Foundation 相似文献
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Brandenburg G Cinabro D Liu T Saulnier M Wilson R Yamamoto H Bergfeld T Eisenstein BI Ernst J Gladding GE Gollin GD Palmer M Selen M Thaler JJ Edwards KW McLean KW Ogg M Bellerive A Britton DI Hyatt ER Janicek R MacFarlane DB Patel PM Spaan B Sadoff AJ Ammar R Baringer P Bean A Besson D Coppage D Copty N Davis R Hancock N Kotov S Kravchenko I Kwak N Kubota Y Lattery M Momayezi M Nelson JK Patton S Poling R Savinov V Schrenk S Wang R Alam MS Kim IJ Ling Z Mahmood AH O'Neill JJ Severini H Sun CR 《Physical review letters》1995,75(21):3804-3808
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Nimai C. Mukhopadhyay J. -F. Zhang R. M. Davidson M. Benmerrouche 《Physics letters. [Part B]》1997,410(2-4):73-78
We examine theoretical implications of studying the differential cross-section and some key polarization observables in the η′ photoproduction reaction off protons, from its threshold to about 2 GeV of cm energy, the region of the so-called “missing baryon resonances”. We compare implications of different models all of which generate the observed peak in the total η′ photproduction cross section, but have very different differential cross section and polarization profields. Their measurements are thus crucial in distinguishing these reaction mechanisms, of interest to understanding QCD in its nonperturbative domain. 相似文献
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