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111.
D. Cortina-Gil T. Baumann H. Geissel H. Lenske K. Sümmerer L. Axelsson U. Bergmann M.J.G. Borge L.M. Fraile M. Hellström M. Ivanov N. Iwasa R. Janik B. Jonson K. Markenroth G. Münzenberg F. Nickel T. Nilsson A. Ozawa K. Riisager G. Schrieder W. Schwab H. Simon C. Scheidenberger B. Sitar T. Suzuki M. Winkler 《The European Physical Journal A - Hadrons and Nuclei》2001,10(1):49-56
One-neutron removal cross-sections ( ) of 17, 19C in various targets at about 900 MeV/nucleon, and one-proton removal cross-sections ( ) of 8, 10B at about 1400 MeV/nucleon were measured using the fragment separator FRS at GSI. A significant increase of for 19C compared to its neighbors was observed. The same behavior was found for for the neutron-deficient nucleus 8B compared to the stable isotope 10B. These results support a one-neutron halo structure in 19C and a one-proton halo in 8B.
Received: 26 July 2000 / Accepted: 11 January 2001 相似文献
112.
Lazareva G. G. Popov V. A. Arakcheev A. S. Burdakov A. V. Schwab I. V. Vaskevich V. L. Maksimova A. G. Ivashin N. E. Oksogoeva I. P. 《Journal of Applied and Industrial Mathematics》2021,15(2):292-301
Journal of Applied and Industrial Mathematics - We study a model of the current distribution during heating of the surface of a tungsten sample under pulsed exposure to an electron beam. The model... 相似文献
113.
Rima Laroum Fabienne Berrée Thierry Roisnel Vincent Dorcet Bertrand Carboni Abdelmadjid Debache 《Tetrahedron letters》2019,60(35):150988
The AlCl3-promoted reactions of cycloalkanones with hydrazones are described. This approach represents a mild and operationally simple method to access 2,3-diaryl-4,5,6,7-tetrahydro-1H-indazoles and their analogues in good to moderate yields. 相似文献
114.
U. Gollerthan T. Brohm H. -G. Clerc E. Hanelt M. Horz W. Morawek W. Schwab K. -H. Schmidt F. P. Heßberger G. Münzenberg V. Ninov R. S. Simon J. P. Dufour M. Montoya 《Zeitschrift für Physik A Hadrons and Nuclei》1991,338(1):51-60
For the compound nucleus179Au formed at an excitation energy of 26 MeV in the fusion reaction90Zr+89Y, the energy spectra of promptly emitted protons,α particles andγ rays were measured in concidence with the evaporation residues. On the basis of the measured total decay energy, the 1p and 1α decay channels were separated from all other evaporation-residue channels. The energy spectra and absolute cross sections, together with previously measured excitation functions for various decay channels, are successfully described by statisticalmodel calculations with the Monte Carlo code CODEX. 相似文献
115.
The anomeric hydroxyl of lactose was carbamoylated selectively by treating the free sugar with alkylisocyanates, thus without preliminary protection of the other hydroxyls of the lactose molecule. Moreover, the readily available 1-aminolactose and 1-octyl-aminolactose reacted with isocyanates and isothiocyanates to afford selectively -lactosyl -alkylureas and -lactosyl -alkylthioureas, respectively. 相似文献
116.
Ricardo S. Schwab Juliano B. Azeredo Diogo S. Lüdtke Márcio W. Paixão 《Tetrahedron letters》2008,49(34):5094-5097
In this Letter, a cysteine-derived prolinamide is described to act as a robust and effective organocatalyst for enantioselective aldol reactions. 相似文献
117.
A. Wolf H. Poth W. Schwab B. Seligmann M. Wörtge H. Haseroth C. E. Hill J. -L. Vallet 《Hyperfine Interactions》1989,44(1-4):217-232
The motivation of using electron cooling in low-energy antiproton storage rings and the expected cooling performance are discussed.
Results obtained recently, during the first operation of electron cooling in LEAR at CERN with a 50 MeV proton beam, are summarized,
concerning in particular the equilibrium beam properties, the recombination between cooling electrons and cooled protons,
and the deceleartion of acceleration of protons by friction in the electron beam. Conclusions are drawn for the formation
of antihydrogen with the cooled antiproton beam, and for the deceleration of antiprotons to energies close to or below 1 MeV. 相似文献
118.
G. Münzenberg P. Armbruster S. Hofmann F. P. Heßberger H. Folger J. G. Keller V. Ninov K. Poppensieker A. B. Quint W. Reisdorf K. -H. Schmidt J. R. H. Schneider H. -J. Schött K. Sümmerer I. Zychor M. E. Leino D. Ackermann U. Gollerthan E. Hanelt W. Morawek D. Vermeulen Y. Fujita T. Schwab 《Zeitschrift für Physik A Hadrons and Nuclei》1989,334(2):163-175
A new and transparent method for the analysis of recoil distance Doppler shift data is presented, which we call thedifferentialdecay curve method (DDCM). The DDCM can be used for singles as well as for coincidence plunger data and systematic errors can be discovered with it much easier than in the conventional analysis. In addition we propose a modification of the normal plunger which we call the differential plunger. With the differential plunger in principle it is possible to determine lifetimes from quantities measured at only one target to stopper distance. The DDCM was tested with lifetime data for120Xe and128Ba. 相似文献
119.
R. S. Simon K. -H. Schmidt F. P. Heßberger S. Hlavac M. Honusek G. Münzenberg H. -G. Clerc U. Gollerthan W. Schwab 《Zeitschrift für Physik A Hadrons and Nuclei》1986,325(2):197-202
Theγ decay in the radiative fusion reaction90Zr+90Zr→180Hg+xγ has been observed in an array of NaI detectors. States up to 6+ in the yrast sequence of180Hg are tentatively assigned and suggest the coexistence of weakly oblate and strongly prolate nuclear shapes. The difference in potential energy between the two inferred shapes has dropped to about 200 keV, continuing the downward trend observed in the heavier even isotopes188–182Hg. 相似文献