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1.
For the determination of the bound-electron g factor
in hydrogen-like heavy ions the mass of the ion is needed at a
relative uncertainty of at least 1 ppb. With the
SMILETRAP Penning trap mass spectrometer at the Manne
Siegbahn Laboratory in Stockholm several mass measurements of ions
with even-even nuclei at this level of precision have been
performed so far, exploiting the fact that the mass precision
increases linearly with the ion charge. Measurements of masses of
the hydrogen-like ions of the two Mg-isotopes 24Mg and
26Mg are reported. The masses of the hydrogen-like ions are
23.979011054(14) u and 25.976562354(34) u,
corresponding to the atomic masses 23.985041690(14) u and
25.982592986(34) u, respectively. The possibility to use
these two isotopes for the first observation of an isotope effect
in the bound-electron g factor in hydrogen-like heavy ions is
discussed. 相似文献
2.
A.B. Mundt A. Kreuter C. Russo C. Becher D. Leibfried J. Eschner F. Schmidt-Kaler R. Blatt 《Applied physics. B, Lasers and optics》2003,76(2):117-124
We demonstrate coherent coupling of the quadrupole S1/2D5/2 optical transition of a single trapped 40Ca+ ion to the standing wave field of a high-finesse cavity. The dependence of the coupling on temporal dynamics and spatial
variations of the intracavity field is investigated in detail. By precisely controlling the position of the ion in the cavity
standing wave field and by selectively exciting vibrational state-changing transitions the ion’s quantized vibration in the
trap is deterministically coupled to the cavity mode. We confirm coherent interaction of ion and cavity field by exciting
Rabi oscillations with short resonant laser pulses injected into the cavity, which is frequency-stabilized to the atomic transition.
Received: 23 August 2002 / Published online: 8 January 2003
RID="*"
ID="*"Corresponding author. E-mail: christoph.becher@uibk.ac.at
RID="**"
ID="**"Present address: Time and Frequency Division, National Institute of Standards and Technology, Boulder, CO 80305, USA 相似文献
3.
A. Merli F. Sauer L. Wöste A. Lindinger 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,42(2):217-220
We report on isotope selective three-photon ionization of
two isotopomers of KRb by applying evolution strategies. The
particularity of this experiment is based on the high resolution
phase and amplitude modulation of the fs-laser pulses provided by a
2 × 640 pixel pulse shaper. The optimization in a closed feedback
loop performed with spectrally broad pulses centered at 840 nm shows
high enhancements of one isotopomer at the expense of the other
isotopomer and vice versa. From the optimal laser field we aim to
gain details about the selective ionization sequence and the
wavepacket evolution on the involved vibrational states. 相似文献
4.
The norm kernel of the A=12 system composed of two 6He clusters, and the L=0 basis functions (in the SU(3) and angular momentum-coupled schemes) are analytically obtained in the Fock-Bargmann space. The norm kernel has a diagonal form in the former basis, but the asymptotic conditions are naturally defined in the latter one. The system is a good illustration for the method of projection of the norm kernel to the basis functions in the presence of SU(3) degeneracy that was proposed by the authors. The coupled-channel problem is considered in the algebraic version of the resonating-group method, with the multiple decay thresholds being properly accounted for. The structure of the ground state of 12Be obtained in the approximation of zero-range nuclear force is compared with the shell-model predictions. In the continuum part of the spectrum, the S-matrix is constructed, the asymptotic normalization coefficients are deduced and their energy dependence is analyzed. 相似文献
5.
T. Shizuma T. Ishii H. Makii T. Hayakawa S. Shigematsu M. Matsuda E. Ideguchi Y. Zheng M. Liu T. Morikawa 《The European Physical Journal A - Hadrons and Nuclei》2007,32(1):1-4
In this paper we present for the first time the measured delayed neutron (DN) yields and time spectra from high-energy protons
interacting with thick natPb targets. The 1GeV protons from the accelerator impinged on targets of different thicknesses producing a huge number of
spallation-fission products, some of which can be DN precursors. After the beam is switched off, the DNs were detected with
optimized 3He counter. The production yields of light DN precursors as 17N and “usual” fission products as 87Br and 88Br, which dominate the total DN activity, are obtained both for thin and thick targets. These new data are of great interest
for the new generation high-power spallation targets based on liquid-metal technologies. Our findings also should help to
constrain the physics models within the simulations codes. 相似文献
6.
In this paper we present an expression relating the cohesive energy (E coh in kcal/mol) of AIIIBV and AIIBVI semiconductors with the product of ionic charges (Z 1 Z 2) and nearest-neighbour distance d (Å). The cohesive energy values of these solids exhibit a linear relationship when plotted on a log-log scale against the nearest-neighbour distance d (Å), but fall on different straight lines according to the ionic charge product of the solids. A good agreement has been found between the experimental and calculated values of the cohesive energy of AIIIBV and AIIBVI semiconductors. 相似文献
7.
8.
Within the framework of the single-channel approximation, an {αtd} model of the 9
Be nucleus is presented. A comparative analysis of the t 6
Li wave functions describing relative motion of bound states constructed in {ααn} and {αtd} cluster representations is carried out on the example of calculations of the 9
Be(γ,t0)6
Li process characteristics.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 1, pp. 85–89, January, 2008. 相似文献
9.
10.
N. G. Peresadko Yu. A. Alexandrov S. G. Gerasimov V. A. Dronov V. G. Larionova A. V. Pisetskaya E. I. Tamm V. N. Fetisov S. P. Kharlamov L. N. Shesterkina 《Physics of Atomic Nuclei》2010,73(11):1942-1947
In a track nuclear photoemulsion exposed to a beam of 7Li nuclei accelerated to a momentum of 3 GeV/c per nucleon at the synchrophasotron of the Joint Institute for Nuclear Research (JINR, Dubna), 13 events in which 7Li nuclei interacting with protons break up into 3H and 4He fragments were detected among 3730 inelastic-interaction events. For this fragmentation channel, the cross section was
found to be 8 ± 2 mb. The average value of the fragment total transverse momentum was 214 ± 5 MeV/c. This value exceeds markedly the average value of the transverse-momentum transfer in the coherent dissociation of 7Li nuclei on track-emulsion nuclei (166±5MeV/c). The recoil-proton transverse momentum was on average 98% of the total proton momentum. The longitudinal-momentum distribution
of protons was characterized by a variance of 16 MeV/c and a mean value of 37 ± 2MeV/c. 相似文献
11.
A. Gay 《The European Physical Journal C - Particles and Fields》2007,49(2):489-497
Understanding the mechanism of electroweak symmetry breaking and the origin of boson and fermion masses is among the most
pressing questions raised in contemporary particle physics. If these issues involve one (several) Higgs boson(s), a precise
measurement of all its (their) properties will be of prime importance. Among those, the Higgs coupling to matter fermions
(the Yukawa coupling). At a linear collider, the process e+e-→tt̄H will allow a direct measurement of the top-Higgs Yukawa coupling. We present a realistic feasibility study of the measurement
in the context of the TESLA collider. Four channels are studied and the analysis is repeated for several Higgs mass values
within the range 120–200 GeV/c
2.
PACS 13.66.Jn; 14.65.Ha; 14.80.Bn 相似文献
12.
Y. Hashimoto M. Kitaoka T. Yoshida S. Hasegawa 《Applied physics. B, Lasers and optics》2011,103(2):339-344
We report the observation of sympathetically cooled 43Ca+ (natural abundance 0.135%) in a linear ion trap utilizing simultaneously trapped isotope ions as coolant. We investigated
different possibilities of realizing efficient sympathetic cooling and observed the peaks of the hyperfine transitions of
43Ca+ under various experimental conditions. 相似文献
13.
Aparajita Dey S. Bhattacharya C. Bhattacharya K. Banerjee T. K. Rana S. Kundu S. R. Banerjee S. Mukhopadhyay D. Gupta R. Saha 《The European Physical Journal A - Hadrons and Nuclei》2009,41(1):39-51
Inclusive energy distributions for light charged particles (p , d , t and have been measured in the 20Ne (158, 170, 180, 200 MeV) + 12C
reactionsintheangularrange$10°$ - - $50°$.Exclusivelight-charged-particleenergydistributionmeasurementswerealsodoneforthesamesystemat158 MeVbombardingenergybyin - planelightchargedparticle - - fragmentcoincidence.Pre - equilibriumcomponentshavebeenseparatedoutfromprotonenergyspectrausingthemovingsourcemodelconsideringtwosources.ThedatahavebeencomparedwiththepredictionsofthestatisticalmodelcodeCASCADE.Ithasbeenobservedthatsignificantdeformationeffectswereneededtobeintroducedinthecompoundnucleusinordertoexplaintheshapeoftheevaporated$d$,$t$energyspectra.Forprotons, evaporatedenergyspectrawereratherinsensitivetonucleardeformation, thoughangulardistributionscouldnotbeexplainedwithoutdeformation.Thedecaysequenceofthehot$32S$nucleushasbeeninvestigatedthroughexclusivelight - - charged - particlemeasurementsusingthe$20Ne$$(158 MeV) + $12C
reaction. Information on the sequential decay chain has been extracted through a comparison of the experimental data with
the predictions of the statistical model. It is observed from the present analysis that exclusive light-charged-particle data
may be used as a powerful tool to probe the decay sequence of hot light compound systems. 相似文献
14.
A. Basu 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2011,61(1):51-55
Electron-hydrogen scattering has been investigated in
Debye plasma environment employing the close-coupling approximation. Two
models, viz., 6-state CCA and 9-state CCA have been used. Plasma screening
has been taken into account via Debye-Hückel model potential. The
lowest lying 1De^1{\rm D}^{{\rm e}} auto-detaching resonance of the hydrogen negative
ion has been successfully predicted for various plasma conditions. The
resonant state changes to shape resonance for Debye scattering lengths less
than a critical value. 相似文献
15.
A. V. Eliseev I. N. Meshkov V. A. Mikhailov A. O. Sidorin 《Physics of Particles and Nuclei Letters》2010,7(7):473-477
The main objective of the NICA project developed at the Joint Institute for Nuclear Research (JINR) is to conduct experimental
studies with colliding heavy ion beams in an energy range of 1–4.5 GeV/nucleonucleon with luminosity on the level of 1 × 1027 cm−2 s−1. In this paper the operation regime of the collider injection chain providing the bunch with experimentally desirable parameters
at the output of the Nuclotron is considered for gold ions as an example. 相似文献
16.
B. V. Zhuravlev A. A. Lychagin N. N. Titarenko V. G. Demenkov V. I. Trykova 《Physics of Atomic Nuclei》2011,74(3):335-340
The spectra of neutrons from the (p, n) reactions on 47Ti, 48Ti, 49Ti, 53Cr, and 54Cr nuclei were measured in the proton-energy range 7–11 MeV. The measurements were performed with the aid of a fast-neutron
spectrometer by the time-of-flight method over the base of the EGP-15 tandem accelerator of the Institute for Physics and
Power Engineering (IPPE, Obninsk). Owing to a high resolution and a high stability of the time-of-flight spectrometer used,
low-lying discrete levels could be identified reliably along with a continuum section of neutron spectra. An analysis of measured
data was performed within the statistical equilibrium and preequilibrium models of nuclear reactions. The relevant calculations
were performed by using the exact formalism of Hauser-Feshbach statistical theory supplemented with the generalized model
of a superfluid nucleus, the back-shifted Fermi gas model, and the Gilbert-Cameron composite formula for the nuclear level
density. The nuclear level densities for 47V, 48V, 49V, 53Mn, and 54Mn were determined along with their energy dependences and model parameters. The results are discussed together with available
experimental data and recommendations of model systematics. 相似文献
17.
Roland Beyer Arnd R. Junghans Peter Schillebeeckx Ivan Sirakov Tae-Yung Song Daniel Bemmerer Roberto Capote Anna Ferrari Andreas Hartmann Ronald Hannaske Jan Heyse Hyeon Il Kim Jong Woon Kim Toni Kögler Cheol Woo Lee Young-Ouk Lee Ralph Massarczyk Stefan E. Müller Tobias P. Reinhardt Marko Röder Konrad Schmidt Ronald Schwengner Tamás Szücs Marcell P. Takács Andreas Wagner Louis Wagner Sung-Chul Yang 《The European Physical Journal A - Hadrons and Nuclei》2018,54(5):81
18.
A.E. Dorokhov E.A. Kuraev Yu.M. Bystritskiy M. Sečanský 《The European Physical Journal C - Particles and Fields》2008,55(2):193-198
We reconsider QED radiative corrections (RC) to the π0→e+e- decay width. One kind of RC investigated earlier has a renormalization group origin and can be associated with the final
state interaction of electron and positron. It determines the distribution of lepton pair invariant masses in the whole kinematic
region. The other type of RC has a double-logarithmic character and is related to almost on-mass-shell behavior of the lepton
form factors. The total effect of RC for π0→e+e- decay is estimated to be 3.2%, and for η→e+e- decay it is 4.3%.
PACS 13.25.Cq; 12.38.Lg; 12.38.-t 相似文献
19.
O. V. Bespalova I. N. Boboshin V. V. Varlamov T. A. Ermakova B. S. Ishkhanov E. A. Romanovskii T. I. Spasskaya T. P. Timokhina 《Bulletin of the Russian Academy of Sciences: Physics》2007,71(3):428-433
The change in the neutron single-particle structure of (1f?2p)-shell magic nuclei near the Fermi energy with an increase in the number of protons in the 1f 7/2 subshell from 0 for 48Ca to 8 for 56Ni has been investigated. Good agreement of the experimental and estimated values of the single-particle energies E nlj of the bound states of neutrons in these nuclei with the results of calculations within the dispersive optical model is obtained. 相似文献
20.
Wei Jiang YanLin Ye ZhiHuan Li ChengJian Lin QiTe Li YuCheng Ge JianLing Lou DongXing Jiang Jing Li ZhengYang Tian Jun Feng Biao Yang ZaiHong Yang Jie Chen HongLiang Zang Qiang Liu PengJie Li ZhiQiang Chen Yun Zhang Yang Liu XiaoHui Sun Jing Ma HuiMing Jia XinXing Xu Lei Yang NanRu Ma LiJie Sun 《中国科学:物理学 力学 天文学(英文版)》2017,60(6):062011
A transfer-reaction experiment of 9Be(9Be, 10Be)8Be was performed at a beam energy of 45 MeV. Excited states in 10Be up to 18.80 MeV are produced using missing mass and invariant mass methods. Most of the observed high-lying resonant states, reconstructed from the α + 6He and t + 7Li decay channels, agree with the previously reported results. In addition, two new resonances at 15.6 and 18.8 MeV are identified from the present measurement. The 18.55 MeV state is found to decay into both the t + 7Lig.s. and t + 7Li* (0.478 MeV) channels, with a relative branching ratio of 0.93 ± 0.33. Further theoretical investigations are encouraged to interpret this new information on cluster structure in neutron-rich light nuclei. 相似文献