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11.
We show that with the weak topology is not an intersection of Borel sets in its Cech-Stone extension (and hence in any compactification). Assuming (CH), this implies that has no continuous injection onto a Borel set in a compact space, or onto a Lindelöf space. Under (CH), this answers a question of Arhangel'ski.
12.
Angular distributions for the 163Dy(t,p) and 177Hf(t,p) reactions were measured using 17 MeV tritons from the McMaster University Tandem Van de Graaff accelerator. Reaction products were analyzed with a magnetic spectrograph and detected with photographic emulsions. Favored L=0 transitions confirmed assignments of the 5/2−[523] band in 165Dy and 7/2−[514] band in 179Hf. Additional L=0 transitions in each nuclide identified previously unknown 5/2− levels in 165Dy and 7/2− ones in 179Hf. Overall trends of L=0 strengths support the existence of subshell closures at neutron numbers 98 and 108. On the basis of a relatively strong L=2 transition, the Kπ=11/2− γ-vibration based on the 7/2−[514] state is identified at 1689 keV in 179Hf, about 440 keV above its previously-assigned Kπ=3/2− partner. 相似文献
13.
14.
Schumm BA Koetke DS Adolphsen CE Alexander JP Averill D Barish BC Barklow T Barnett BA Blockus D Boyarski A Brabson B Breakstone A Bulos F Burchat PR Burke DL Cence RJ Chapman J Chmeissani M Cords D Coupal DP Dauncey P DeStaebler HC Dorfan JM Drell PS Drewer DC Durrett D Elia R Feldman GJ Field RC Ford WT Fordham C Frey R Fujino D Gan KK Gero E Gidal G Glanzman T Goldhaber G Gomez Cadenas JJ Gratta G Hanson G Harr R Harral B Harris FA Hayes K Hearty C Heusch CA Hildreth MD Himel T Hinshaw DA 《Physical review D: Particles and fields》1992,46(1):453-456
15.
Ong RA Weir AJ Abrams GS 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 Perl ML Petersen A Richter B Riles K Rowson PC Schaad T Schellman H Schmidke WB Sheldon PD Trilling GH Wood DR Yelton JM 《Physical review letters》1988,60(25):2587-2590
16.
de la Vaissiere C Luth V Abrams GS Amidei D Baden AR Barklow T Boyarski AM Boyer J Breidenbach M Burchat P Burke DL Butler F Dillon JW Dorfan JM Feldman GJ Gidal G Gladney L Gold MS Goldhaber G Golding LG Hanson G Haggerty J Herrup D Himel T Hollebeek RJ Innes WR Jaros JA Juricic I Kadyk JA Klein SR Lankford AJ Larsen RR LeClaire BW Levi ME Lockyer NS Matteuzzi C Nelson ME Ong RA Perl ML Richter B Ross MC Rowson PC Schaad T Schellman H Schmidke WB Sheldon PD Trilling GH Yelton JM Wood DR 《Physical review letters》1985,54(19):2071-2074
17.
Gidal G Boyer J Butler F Cords D Abrams GS Amidei D Baden AR Barklow T Boyarski AM Burchat P Burke DL Dorfan JM Feldman GJ Gladney L Gold MS Goldhaber G Golding LJ 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 ME Lockyer NS Lüth V Matteuzzi C Nelson ME Ong RA Perl ML Richter B Riles K Rowson PC Schaad T Schellman H Schmidke WB Sheldon PD Trilling GH de la Vaissière C Wood DR Yelton JM Zaiser C 《Physical review letters》1987,59(18):2016-2019
18.
Klein SR Himel TM 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 Lankford AJ Larsen RR LeClaire BW Levi M Lockyer NS Lüth V Matteuzzi C Nelson ME Ong RA Perl ML Petersen A Richter B Riles K Rowson PC Schaad T Schellman H Schmidke WB Sheldon PD Trilling GH de la Vaissiere C Wood DR Yelton JM 《Physical review letters》1987,58(7):644-647
19.
Proton states in theN = 86 nuclei147Pm and149Eu populated in the (3He,d), (α,t) and (t, α) reactions
The (3He,d) and (α, t) reactions on targets of146Nd and148Sm have been studied, using beams of 24 MeV3He and 27 MeV4He from the McMaster University tandem van de Graaff accelerator. Also the (t, α) reaction on a target of148Sm has been studied, using 17 MeV tritons from the Los Alamos Scientific Laboratory tandem accelerator. The reaction products were analyzed with magnetic spectrographs. Information on thel-values was obtained from (3He,d) angular distributions and from ratios of (α,t) and (3He,d) cross sections. In each nucleus a severe fragmentation of the shell-model strength is found. In particular a total of 13(7)l=2 transitions and 6(6)l=0 transitions have been identified in147Pm(149Eu). The results are analyzed in terms of the spherical shell model, which accounts fairly well for the summed spectroscopic strengths. However, with the existence of the (t, α) data a more detailed investigation of the emptiness of individual levels observed in147Pm gives some indication that a deformed scheme might be more successful in describing these nuclei. 相似文献
20.
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