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1.
V. R. Brown B. F. Gibson J. A. Carlson R. Schiavilla 《The European Physical Journal A - Hadrons and Nuclei》2003,18(2-3):289-291
The parity-non-conserving longitudinal asymmetry in proton-proton (p
p) elastic scattering is calculated in the lab energy range 0-350 MeV using contemporary, realistic strong-interaction potentials combined with a weak-interaction potential comprised of
- and
-meson exchanges as exemplified by the DDH model. Values for the
- and
-meson coupling constants,
and
, are determined from comparison with the measured asymmetries at 13.6 MeV, 45 MeV, and 221 MeV.Received: 30 September 2002, Published online: 22 October 2003PACS:
21.30.-x Nuclear forces - 24.80. + y Nuclear tests of fundamental interactions and symmetries - 25.40.Cm Elastic proton scattering 相似文献
2.
X. Z. Cai C. Zhong W. Q. Shen Y. G. Ma H. Y. Zhang Y. B. Wei J. G. Chen W. Guo K. Wang G. L. Ma X. F. Zhou 《The European Physical Journal A - Hadrons and Nuclei》2004,20(2):263-267
,
and
have been calculated via the BUU model with soft EOS and 0.8 times of
. The density distribution without any adjustable parameters which comes from the RMF model has been introduced into the BUU calculation to replace the normally used one-parameter square-type distribution. The calculated results can reproduce the experimental data well for both halo- and stable-nuclei-induced reactions. Here
or
is calculated as the difference between
of halo nucleus and core nucleus, by assuming
. It indicates that this assumption works very well at high energy in the BUU calculation. More experimental measurements are necessary to test the validity of this assumption at intermediate energy.Received: 12 June 2003, Revised: 29 September 2003, Published online: 27 April 2004PACS:
24.10.-i Nuclear reaction models and methods - 25.60.Dz Interaction and reaction cross-sections - 25.60.Gc Breakup and momentum distributions - 27.20. + n
相似文献
3.
Exotic, neutron-rich proton-induced spallation products of 232Th and 238U obtained from the PS Booster ISOLDE facility have been investigated by
-
,
-
coincidence and spectrum-multiscaling measurements. A new method for the reduction of isobaric contamination enabled to study the unknown region beyond 208Pb for the decay chain A = 217. A new isotope 217Bi with a half-life of
s was discovered and its
-decay studied. For the first time, a half-life value of
s for the
-decay of 217Po was measured.Received: 3 March 2003, Revised: 13 May 2003, Published online: 30 September 2003PACS:
23.20.Lv
transitions and level energies - 23.60.+e
decay - 27.80.+w 190
A
219 - 29.30.Kv X- and
-ray spectroscopyV. Fedoseyev: Present address: ISOLDE, CERN-PPE, CH-1211, Geneva 23, Switzerland.M. Górska: Present address: GSI, Darmstadt, D-64220, Germany.M. Huhta: Present address: Nokia, Tampere, Finland. 相似文献
4.
P. Kowina M. Wolke H. -H. Adam A. Budzanowski R. Czyżykiewicz D. Grzonka J. Haidenbauer M. Janusz L. Jarczyk A. Khoukaz K. Kilian P. Moskal W. Oelert C. Piskor-Ignatowicz J. Przerwa C. Quentmeier T. Rożek R. Santo G. Schepers T. Sefzick M. Siemaszko J. Smyrski S. Steltenkamp A. Strzałkowski P. Winter P. Wüstner W. Zipper 《The European Physical Journal A - Hadrons and Nuclei》2004,22(2):293-299
The production of the
- and
-hyperons has been measured via the
reaction at the internal COSY-11 facility in the excess energy range between 14 and 60 MeV. The transition of the
cross-section ratio from about 28 at
MeV to the high-energy level of about 2.5 is covered by the data showing a strong decrease of the ratio between 10 and 20 MeV excess energy. Effects from the final-state interactions in the p-
channel seem to be much smaller than in the p-
channel. Estimates of the effective range parameters are given for the
and the
systems.PACS:
13.75.-n Hadron-induced low- and intermediate-energy reactions and scattering (energy
GeV) - 13.75.Ev Hyperon-nucleon interactions - 13.85.Lg Total cross-sections - 25.40.Ep Inelastic proton scattering 相似文献
5.
M. J. Vicente Vacas 《The European Physical Journal A - Hadrons and Nuclei》2003,18(2-3):479-481
The
interaction in the scalar isoscalar channel is studied as a function of the baryonic density in the framework of a chiral unitary approach which successfully reproduces vacuum
-
phase shifts. We present some results on the
-meson pole, which is generated dynamically in our model, in nuclear matter. Finally, we analyze the (
) reaction on nucleons and nuclei in the kinematical region where the scalar isoscalar
scattering amplitude is influenced by the low mass of the
in nuclei, and thus, presents a large enhancement close to the position of its pole. Indeed, we find, that the final-state interaction of the pions modified by the nuclear medium produces a large shift of strength of the two-pion invariant-mass distribution in the (
) channel consistent with recent experimental data.Received: 30 September 2002, Published online: 22 October 2003PACS:
14.40.-n Properties of specific particles: Mesons - 25.20.-x Photonuclear reactions - 21.65. + f Nuclear matter 相似文献
6.
Isomeric states in 210-215Ra have been populated by the decay of the compound nuclei 216,220Ra produced in irradiations of 204,208Pb with 12C at
MeV. Published values for
-ray energies and half-lives were confirmed for
Ra. Our data for
Ra agree with the
-energies and the half-life measured at the RITU separator, University of Jyväskylä (Finland). Its decay pattern is complex. Two series of
-rays of
keV and
keV were observed. A half-life of
s was measured. The isomeric state is attributed to an 8 + state at E
* = 2053.8keV. A previously unknown isomeric state was assigned to
Ra. It has a half-life of (
)
and it decays by emission of
-rays with energies of 396.1keV and 802.0keV. It is attributed to a 13/2 + state at E
* = 1198.1 keV.PACS:
23.60. + e
decay - 27.90. + b
相似文献
7.
W. Cassing 《The European Physical Journal A - Hadrons and Nuclei》2003,18(2-3):467-470
The production and decay of vector mesons (
) in pA and AA reactions is studied with particular emphasis on their in-medium spectral functions. It is explored within transport calculations if hadronic in-medium decays like
or
might provide complementary information to their dilepton (e
+
e
-) decays. Whereas the
signal from the
-meson is found to be strongly distorted by pion rescattering, the
-meson Dalitz decay to
appears promising even for more heavy nuclei in
and pA reactions. Furthermore, the influence of nucleon and kaon/antikaon potentials on the
yields and spectra in pA collisions is calculated and compared to the recent data from the ANKE Collaboration.Received: 30 September 2002, Published online: 22 October 2003PACS:
13.60.Le Meson production - 13.75.Jz Kaon-baryon interactions - 14.40.Aq
, K, and
mesons - 25.40.-h Nucleon-induced reactionsW. Cassing: In collaboration with E.L. Bratkovskaya, M. Büscher, Ye.S. Golubeva, V. Grishina, V. Hejny, V. Metag, J. Messchendorp, B. Kamys, L.A. Kondratyuk, P. Kulessa, Z. Rudy, S. Schadmand, A.A. Sibirtsev, H. Ströher 相似文献
8.
The
-decay of 149Ba to 149La has been investigated by means of
- and X-ray spectroscopy, and a partial level scheme of 149La has been constructed for the first time. It includes thirteen
-rays and ten excited states. The exotic 149La is the heaviest lanthanum for which spectroscopic information is now available. We have applied the shell correction approach with the axially deformed Woods-Saxon potential in order to calculate the deformation energy for the 149La ground state. The deformed ground state was found at
0.23,
0 and
0.12.Received: 18 July 2003, Revised: 12 January 2004, Published online: 26 May 2004PACS:
27.60. + j
- 29.30.Kv X- and
-ray spectroscopy 相似文献
9.
We demonstrate the different effect of strange impurities (
and
) on the static properties of nuclei within the framework of the relativistic mean-field model. Systematic calculations show that the glue-like role of the
-hyperon is universal for all
-hypernuclei considered. However, the
-hyperon has a glue-like role only for the protons distribution in nuclei, while for the neutrons distribution it plays a repulsive role. On the other hand, the
-hyperon attracts the surrounding neutrons and reveals a repulsive force to the protons. Possible explanations of the above observation are discussed.Received: 10 March 2003, Revised: 6 November 2003, Published online: 5 May 2004PACS:
21.80. + a Hypernuclei - 24.10.Cn Many-body theory 相似文献
10.
We study kaonic hydrogen, the bound K
-
p state A
K p
. Within a quantum field theoretic and relativistic covariant approach we derive the energy level displacement of the ground state of kaonic hydrogen in terms of the amplitude of K
-
p scattering for arbitrary relative momenta. The amplitude of low-energy K
-
p scattering near threshold is defined by the contributions of three resonances
,
and
and a smooth elastic background. The amplitudes of inelastic channels of low-energy K
-
p scattering fit experimental data on the near-threshold behaviour of the cross-sections and the experimental data by the DEAR Collaboration. We use the soft-pion technique (leading order in Chiral Perturbation Theory) for the calculation of the partial width of the radiative decay of pionic hydrogen
and the Panofsky ratio. The theoretical prediction for the Panofsky ratio agrees well with experimental data. We apply the soft-kaon technique (leading order in Chiral Perturbation Theory) to the calculation of the partial widths of radiative decays of kaonic hydrogen
and
. We show that the contribution of these decays to the width of the energy level of the ground state of kaonic hydrogen is less than 1
.Received: 7 October 2003, Revised: 29 November 2003, Published online: 22 June 2004PACS:
11.10.Ef Lagrangian and Hamiltonian approach - 13.75.Gx Pion-baryon interactions - 21.10.-k Properties of nuclei; nuclear energy levels - 36.10.-k Exotic atoms and molecules (containing mesons, muons, and other unusual particles)A.N. Ivanov: Permanent address: State Polytechnical University, Department of Nuclear Physics, 195251 St. Petersburg, Russian FederationN.I. Troitskaya: Permanent address: State Polytechnical University, Department of Nuclear Physics, 195251 St. Petersburg, Russian Federation. 相似文献
11.
A. Sibirtsev 《The European Physical Journal A - Hadrons and Nuclei》2003,18(2-3):475-478
We investigate the
decay width of excited charmonium states at finite nuclear density with simultaneous modification of both D- and
-mesons in nuclear matter. The strongest effect is found for the
-meson. The medium modification can be detected by dilepton spectroscopy as substantial
broadening and anomalous
absorption.Received: 30 September 2002, Published online: 22 October 2003PACS:
13.25.Gv Decays of
,
, and other quarkonia - 14.40.Lb Charmed mesons - 14.65.Dw Charmed quarks - 24.85. + p Quarks, gluons, and QCD in nuclei and nuclear processes 相似文献
12.
Ts Venkova R. M. Lieder W. Gast D. Bazzacco G. de Angelis E. Podsvirova H. M. Jäger L. Mihailescu R. Menegazzo S. Lunardi C. Rossi Alvarez C. Ur T. Martinez M. Axiotis D. Napoli W. Urban T. Rzaca-Urban 《The European Physical Journal A - Hadrons and Nuclei》2003,18(4):577-581
High-spin states in the odd-proton nucleus 173Lu have been populated in a 170Er(7Li,4n) reaction and the emitted
-radiation was detected with the GASP array. The favoured and unfavoured sequences of the
band have been considerably extended. The favoured sequence does not show any indication of a band crossing up to a rotational frequency of
0.45 MeV. This is the largest crossing frequency ever observed for 1/2- [541] bands of odd-proton nuclei with
and
. Previous Cranked Shell Model (CSM) calculations underestimate the crossing frequency by 100 keV.Received: 19 May 2003, Published online: 11 November 2003PACS:
21.10.-k Properties of nuclei; nuclear energy levels - 21.10.Re Collective levels - 23.20.Lv
transitions and level energies - 27.70. + q
相似文献
13.
A. N. Andreyev D. Ackermann F. P. Heßberger S. Hofmann M. Huyse I. Kojouharov B. Kindler B. Lommel G. Münzenberg R. D. Page K. Van de Vel P. Van Duppen K. Heyde 《The European Physical Journal A - Hadrons and Nuclei》2003,18(1):55-64
Alpha-decay of the new nuclide 184Bi has been studied in the complete-fusion reaction 93Nb(94Mo, 3n)184Bi at the velocity filter SHIP. The evaporation residues were separated in-flight and subsequently identified on the basis of recoil-
, recoil-
-
analysis and excitation functions measurements. Two
-decaying isomeric states in 184Bi with half-life values of 13(2) ms and 6.6(1.5) ms were identified. The
-branching ratio of 180Tl was deduced for the first time as
. Improved data on the fine-structure
-decay of 186Bi were obtained in the 93Nb(95Mo, 2n)186Bi reaction. A similarity of the decay energies and half-life values of 184,186Bi is pointed out and a possible explanation for this effect is suggested.Received: 14 March 2003, Revised: 29 April 2003, Published online: 2 September 2003PACS:
23.60.+e
decay - 27.70.+q
- 27.80.+w
K. Heyde: Present address: EP-ISOLDE, CERN, CH-1211, Geneva 23, Switzerland. 相似文献
15.
A. N. Andreyev D. Ackermann S. Antalic H. J. Boardman P. Cagarda J. Gerl F. P. Heßberger S. Hofmann M. Huyse D. Karlgren A. Keenan H. Kettunen A. Kleinböhl B. Kindler I. Kojouharov A. Lavrentiev C. D. O’Leary M. Leino B. Lommel M. Matos C. J. Moore G. Münzenberg R. D. Page S. Reshitko S. Saro H. Schaffner C. Schlegel M. J. Taylor K. Van de Vel P. Van Duppen L. Weissman K. Heyde 《The European Physical Journal A - Hadrons and Nuclei》2003,18(1):39-54
Detailed fine-structure
-decay studies of 188,190Bi were performed using the complete-fusion reactions of 50,52Cr ions with a 142Nd target at the velocity filter SHIP. The evaporation residues were separated in-flight and subsequently identified on the basis of recoil-
, recoil-
-
/X-ray and excitation function measurements. Improved data on the
-decay of 188,190Bi were obtained and a number of new low-lying excited states in the daughters 184,186Tl were observed. An intruder, presumably 10- state was identified in 184Tl, extending the systematics of such states in the odd-odd Tl nuclei beyond the neutron mid-shell at N = 104. Some technical aspects of experiment at recoil separators are also discussed.Received: 14 March 2003, Revised: 1 May 2003, Published online: 2 September 2003PACS:
23.60.+e
decay - 27.70.+q
- 27.80.+w
C.D. OLeary: Present address: Department of Physics, University of York, York, UK.M.J. Taylor: Present address: Department of Physics and Astronomy, Rutgers Univesity, NJ, USA.L. Weissman: Present address: NSCL, Michigan State University, East Lansing, MI 48824-1321 USA.K. Heyde: Present address: EP-ISOLDE, CERN, CH-1211, Geneva 23, Switzerland. 相似文献
16.
A high-quality double-polarization data set for the helicity dependence of the total and differential cross-sections for both
channels in the
region has been obtained in the framework of the GDH experiment. The experiment, performed at the Mainz microtron MAMI, used a 4
detection system, a circularly polarized photon beam, and a longitudinally polarized frozen-spin target. These data are included in the database to perform a multipole analysis to determine the properties of the
-resonance. For the resonant
(1232) multipoles we find a very good agreement with previous analyses, while the nonresonant ones show significant deviations.Received: 11 July 2003, Revised: 16 January 2004, Published online: 17 August 2004PACS:
13.60.Le Meson production - 14.20.Gk Baryon resonances with S = 0 - 25.20.Lj Photoproduction reactions 相似文献
17.
Gyürky Gy. Fülöp Zs. Somorjai E. Kiss G. Rolfs C. 《The European Physical Journal A - Hadrons and Nuclei》2004,20(2):355-358
The absolute strengths of the
keV resonance in the
reaction and of the
keV resonance in the
reaction have been measured to
meV and
meV, respectively, in good agreement with previous values. These resonances can be used to measure the absolute acceptance of the recoil separator ERNA to a precision of about 10%.Received: 12 December 2003, Revised: 10 February 2004, Published online: 3 August 2004PACS:
24.30.-v Resonance reactions - 25.40.Lw Radiative capture - 26.20. + f Hydrostatic stellar nucleosynthesis 相似文献
18.
A short summary of the present status of prompt particle decays in the mass
region is presented. It includes recent results from a GAMMASPHERE experiment, which aimed at the combined high-resolution spectroscopy of light charged particles and
-rays to allow for more detailed studies of known decays and the identification of new cases of discrete prompt proton and
-particle emission from highly and superdeformed states.Received: 10 October 2002, Published online: 17 February 2004PACS:
23.50. + z Decay by proton emission - 23.60. + e
decay - 27.40. + z
- 27.50. + e
相似文献
19.
J. Kurpeta A. Plochocki A. N. Andreyev J. Äystö A. De Smet H. De Witte A.-H. Evensen V. Fedoseyev S. Franchoo M. Górska H. Grawe M. Huhta M. Huyse Z. Janas A. Jokinen M. Karny E. Kugler W. Kurcewicz U. Köster J. Lettry A. Nieminen K. Partes M. Ramdhane H. L. Ravn K. Rykaczewski J. Szerypo K. Van de Vel P. Van Duppen L. Weissman G. Walter A. Wöhr 《The European Physical Journal A - Hadrons and Nuclei》2003,18(1):31-37
A new high-spin isomer in 215Bi, with a half-life of 36.9(6) s, has been identified at the PSB-ISOLDE on-line mass separator using the pulsed-release technique combined with the element selective RILIS source. A decay scheme of
Bi was constructed and complemented with the low-spinstructure observed in
Bi decay. The population of a cascade on top of the
level in 215Poprovides evidence for Gamow-Teller
-decay of the high-spin 215Bi isomer.Received: 3 March 2003, Revised: 10 June 2003, Published online: 9 October 2003PACS:
23.20.Lv
transitions and level energies - 27.80.+w
- 29.30.Kv X- and
-ray spectroscopyV. Fedoseyev: Present address: ISOLDE, CERN-PPE, CH-1211, Geneva 23, Switzerland.M. Górska: Present address: GSI, Darmstadt, D-64220, Germany.M. Huhta: Present address: Nokia, Tampere, Finland. 相似文献
20.
F. P. Heßberger S. Hofmann D. Ackermann P. Cagarda R. -D. Herzberg I. Kojouharov P. Kuusiniemi M. Leino R. Mann 《The European Physical Journal A - Hadrons and Nuclei》2004,22(3):417-427
The isotopes 251No and 253No were produced in nuclear reactions 206Pb(48Ca,3n)251No and 207Pb (48Ca,2n)253No. Radioactive decay of these isotopes and their daughter products has been investigated by means of
- and
-
- spectroscopy. An isomeric state 251m
No, having a half-life of
s and decaying by emission of
particles of
keV was identified. The measured decay data allowed for the construction of partial level schemes for 251No, 247,249Fm and 243,245Cf and an extrapolation of energy systematics of single particle levels of N = 145, 147 and 149 isotones with even Z towards higher atomic numbers up to Z = 102.PACS:
23.60. + e
decay - 27.90. + b
- 21.10.-k Properties of nuclei; nuclear energy levels 相似文献