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This paper reviews the past, present and future status of recoil-isomer tagging at the University of Jyväskylä. The main focus of this research has been to access isomeric states at and beyond the mass ≈140 proton drip line. Recoil-isomer tagging was first used at the University of Jyväskylä in 1998 to establish the prompt rotational band built upon a Kπ = 8- isomeric state in 138Gd. Since that time a series of experiments have been performed which have studied isomeric states in the N = 77 isotones 63140Eu77, 65142Tb77 and 67144Ho77, and in the N = 74 K-isomer chain, 64138Gd74 and 66140Dy74. These experiments have revealed valuable first information about deformations, single-particle excitation energies and hindrance factors in nuclei at and beyond the proton drip line where little or no information previously existed. The results of the most-recent experiments were discussed. These experiments established new isomeric states in 66143Dy77, 61136Pm75, and 64137Gd73 and a further two isomers which are currently unplaced. The paper concludes with a discussion of the future prospects for this research including the increased efficiency of the recoil-isomer tagging technique with a new Multi-Wire Proportional Counter (MWPC) detector which was designed and built at the University of Manchester. The first results from this new setup were shown. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Two-proton radioactivity was predicted more than 40 years ago. According to recent theoretical predictions, proton drip-line nuclei in the A=40–55 region were identified as the most promising candidates. The recent observation of two-proton radioactivity of 45Fe confirmed these predictions nicely. In the present paper, we will summarize experimental results for the decay of 45Fe, which include data from the 2002 discovery of this radcioactivity, but also new data. In addition, we will report on the first observation of 54Zn and its decay by two-proton radioactivity, the second case of this new decay mode. Finally, we will discuss tentative evidence for a small two-proton radioactivity branch for 48Ni. These experimental results are confronted to modern theories which succeed in describing reasonably well this decay mode. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Proton and neutron data as well as photon data are necessary in various intermediate energy applications. To meet these requirements, many groups in the world continue some activities concerning nuclear data evaluation in the energy range above 20 MeV, which is the upper limit of conventional general-purpose evaluated nuclear data files. In this paper, reviewed is brief history of intermediate energy nuclear data development as well as Pearlstein’s contribution for it. Present status of world evaluated nuclear data files in the intermediate energy region is reported as well as evaluation methodology and sample results of evaluation and integral benchmark tests by using the case of JENDL High Energy File as an example. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

A new evaluated nuclear data library has been created. The library consists of two sub-libraries for neutron and proton incident particles. The first version of neutron sub-library has been completed and described in the present paper. The library contains nuclear data for transport, heating, and shielding applications for 242 nuclides ranging in atomic number from 8 to 82 in the energy region of primary neutrons from 10-5 eV to 150 MeV. Data below 20 MeV are taken mainly from ENDF/B-VI (Revision 8) and for some nuclides, from the JENDL-3.3 and JEFF-3.0 libraries. The evaluation of emitted particle energy and angular distributions at the energies above 20 MeV was performed with the help of the ALICE/ASH code and the analysis of available experimental data. The total cross sections, elastic cross sections, and elastic scattering angular distributions were calculated with the help of the coupled channel model. The results of the calculation were adjusted to the data from ENDF/B-VI, JENDL-3.3m or JEFF-3.0 at the neutron energy equal to 20 MeV. The library is written in ENDF/B-VI format using the MF=3/MT=5 and MF=6/MT=5 representations. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

The mass distributions of fragments produced by proton-induced fission of 232Th, 235U, 238U, and 237Np at proton energies of 50 and 96 MeV have been measured. The measurements were carried out at The Svedberg Laboratory, Uppsala, Sweden using a high-precision time-of-flight spectrometer for fission fragments and fission neutrons. The measured mass distributions are compared to ones calculated using the TALYS code. Using proton-induced reactions to simulate the outcome of more difficult measurements with neutron beams is discussed. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

A scattering study of ∼ 30 keV neutrons from H2O, D2O and H2O/D2O mixtures was carried out to search for a ∼ 40% anomalous drop in the n-p scattering cross section. Such an anomaly was reported using 10–200eV neutrons scattered from many H-containing compounds. The anomaly was attributed to n-scattering from quantum entangled proton pairs in the sample. In the present measurement no anomaly was observed. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

The challenging task of predicting nuclear masses is analyzed as a pattern recognition problem on the N-Z plane. A well defined pattern is built by taking the differences between measured masses and Liquid Drop Model (LDM) predictions. After removing the smooth LDM mass contributions, what remains are the microscopic components, which have proved to be extremely hard to model and predict. These contain the information related with shell closures, nuclear deformations, and the residual nuclear interactions. In the present work the more than 2000 known nuclear masses are studied as an array in the N-Z plane viewed through a mask, behind which are hidden the unknown 7000 unstable nuclei that can exist between the proton and neutron drip lines. Employing a Fourier transform deconvolution method these masses are predicted. Measured masses are reconstructed with and r.m.s. error of less than 200 keV . The existence of an island of stability around (Z≈ 116, N≈ 194) is strongly suggested. Different potential applications of the present approach are outlined. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

The discovery of the currently known most neutron- and proton-rich nuclei is compiled. The compilation includes the year and method of discovery of the last known bound and the first unbound nuclei along the neutron and proton driplines. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

We study both polarized and unpolarized proton structure functions in the kinematical region of large Bjorken x and four-momentum tranfer of few GeV2, characterized by the phenomenon of parton-hadron duality between the smooth continuation of the deep inelastic scattering curve and the average of the nucleon resonances which dominate this region. We present results on a perturbative-QCD analysis using recent accurate data aimed at extracting the infrared behavior of the nucleon structure functions. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

Polarized antiprotons produced by spin filtering with an internal polarized gas target provide access to a wealth of single- and double-spin observables, thereby opening a window to physics uniquely accessible with the HESR at FAIR. This includes a first measurement of the transversity distribution of the valence quarks in the proton, and a first measurement of the moduli and the relative phase of the time-like electric and magnetic form factors GE,M of the proton. In polarized and unpolarized pp elastic scattering open questions like the contribution from the odd charge-symmetry Landshoff-mechanism at large |t| and spin-effects in the extraction of the forward scattering amplitude at low |t| can be addressed. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

One of the signature features of Raman’s work was the love and exploitation of nuclear systematics as a tool to discern interesting structural phenomena and to understand better the evolution of structure with nucleon number. Such a tool, properly used, can be extremely powerful, especially when data are correlated with a physically meaningful variable that yields simple and compact trajectories. It can reveal trends that reflect basic elements of nucleonic interactions, it can reveal nuclei with special symmetries, or anomalous nuclei, and it can point to possibly incorrect measurements. We focus on several uses of correlations of nuclear data, illustrating the above ideas. Particular aspects are proton-neutron interactions, quadrupole collectivity, the search for phase transitional behavior and critical point nuclei, and a new mapping of collective nuclear structure across large parts of the nuclear chart, leading to a discovery of an “arc of regularity” characterizing certain nuclei while others nearby in Z and N exhibit chaotic spectra. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

Excitation functions of proton (natPt(p,xn)191,192,193,194,195,196m,g,196m2,198gAu, natPt(p,x)188,189,191,195mPt, natPt(p,x)188,189,190,192,194mIr), deuteron (natPt(d,xn)192,193,194,195,196m,196Au, natPt(d,x)195m,197Pt, natPt(d,x)192Ir) and alpha induced (natPt(α,xn)192g,193m,193g,195m,195g,197m,197g,199mHg, natPt(α,x)194,195g,196m,196g,198m,198g,199,200m,200gAu, natPt(α,x)195m,197m,197gPt) nuclear reactions on platinum target were measured for the first time. The experimental results were compared with the theoretical calculations using the ALICE-IPPE code. The possible applications of the data are discussed. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

Two-proton removal in 17Ne at energies from 60 to 710 A MeV in the carbon target is studied in the eikonal approximation of the Glauber model. The excitation of the 15O core fragment is taken into account. The calculated proton removal cross section in 17Ne, the 17Ne and 15O interaction cross sections are compared to the available experimental data. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]