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The structure of very heavy and superheavy nuclei (SHN) as well as the location of the next proton and neutron shell closures beyond 208Pb is still one of the most intriguing topics in modern nuclear physics [1]. Worldwide competitive, high beam intensities provided by the accelerator facility SPIRAL2 at GANIL which started operation recently, will cover in future all ions up to uranium thanks to the new injector project NEWGAIN. Combined with the separator-spectrometer installation S3 [3], it will provide the instrumental prerequisites for an ambitious science program. Apart from SHN/SHE research, the envisaged physics case at S3 covers, among other, the structure of N=Z nuclei, low energy physics (fundamental properties of the atomic nucleus etc.), interdisciplinary research, atomic physics and reaction studies (fission, deep inelastic reactions etc.). The state of the art of the field is discussed in this paper with an emphasis on the role of the odd particle(s) in odd-even, even-odd and odd-odd nuclei and the consequences for nuclear structure features like K-isomers, trends of single-particle energies as a function of deformation, and the competition of spontaneous fission (SF) and α decay. As an alternative approach to produce heavy and in particular more neutron-rich nuclear species multi-nucleon transfer reactions are briefly discussed as well. [ABSTRACT FROM AUTHOR]

Reactions of weakly bound stable and unstable nuclei have been extensively investigated for several decades. Unique structural effects and breakup mechanisms of weakly bound nuclei have consistently been focal points in the research of nuclear physics, especially at energies around the Coulomb barrier. This paper will review the recent experimental researches performed by the Nuclear Reaction Group at the China Institute of Atomic Energy on weakly bound nuclear reactions in the near-barrier energy region. A anomalous threshold phenomenon in the optical potentials of the 6He + 208Bi system has been observed. Results indicate that the dispersion relation cannot describe the relation between the real part and imaginary part of the optical potential. Moreover, breakup mechanisms of stable weakly bound nuclei 6,7Li as well as proton-rich nuclei 17F and 8B have been studied. The similarities and differences in breakup mechanisms and their effects are discussed. [ABSTRACT FROM AUTHOR]

The structure of very heavy and superheavy nuclei (SHN) as well as the location of the next proton and neutron shell closures beyond 208Pb is still one of the most intriguing topics in modern nuclear physics [1]. Worldwide competitive, high beam intensities provided by the accelerator facility SPIRAL2 at GANIL which started operation recently, will cover in future all ions up to uranium thanks to the new injector project NEWGAIN. Combined with the separator-spectrometer installation S3 [3], it will provide the instrumental prerequisites for an ambitious science program. Apart from SHN/SHE research, the envisaged physics case at S3 covers, among other, the structure of N=Z nuclei, low energy physics (fundamental properties of the atomic nucleus etc.), interdisciplinary research, atomic physics and reaction studies (fission, deep inelastic reactions etc.). The state of the art of the field is discussed in this paper with an emphasis on the role of the odd particle(s) in odd-even, even-odd and odd-odd nuclei and the consequences for nuclear structure features like K-isomers, trends of single-particle energies as a function of deformation, and the competition of spontaneous fission (SF) and α decay. As an alternative approach to produce heavy and in particular more neutron-rich nuclear species multi-nucleon transfer reactions are briefly discussed as well. [ABSTRACT FROM AUTHOR]

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]

The women physicists whose work will be featured are Marietta Blau, Madelaine Forro Barnothy, Phyllis Freier, and Connie Dilworth. The "gluons" that connected their lives to each other (and to the author) included Georges Lemaitre, Manuel Sandoval Vallarta, Cecil Powell, Guiseppi Occhialini, Ken Greisen, Beatrice Tinsley, Hannelore Sexl, and perhaps Elizabeth Rona. Most of the stories are not entirely happy ones. For instance it was Sandoval Vallarta who offered Blau (and her mother) refuge in Mexico when they had to leave Vienna. Vallarta was also Lemaitre's collaborator in calculations of how cosmic rays got to us through the earth's magnetic field. The sad part there is that somehow Lemaitre was never disabused of the view that cosmic rays were direct remnants of his primordial atom and not primarily protons. The result was his gradual exile from main-stream scientific communities. [ABSTRACT FROM AUTHOR]

Gamma-ray bursts (GRBs) are possible sources of ultra-high-energy cosmic rays (UHE-CRs). To test the GRB origin of UHECRs, it is essential to search for characteristic, proton-induced signatures of secondary radiation. In this paper we present our recent results of Monte Carlo simulations that model the broadband prompt emission of GRBs including various processes associated with electrons and protons accelerated to high energies. The most notable effect of accelerated protons on the high-energy spectra is the synchrotron emission from secondary electron-positron pairs injected by photomeson interactions. Secondary photons tend to make the spectra flat, so a spectral flattening in the GeV-TeV bands may serve as a signature of UHECR acceleration. In some cases, the proton-induced photons overwhelm the photon field, resulting in a spectral peak due to inverse Compton emission from secondary pairs located around 107 eV. We can expect to detect synchrotron photons from protons or muons. Observations with GLAST or with atmospheric Cerenkov telescopes can provide useful estimates of the bulk Lorents factor and can constrain the proton acceleration efficiency. [ABSTRACT FROM AUTHOR]

Some of the most fascinating questions about the limits of nuclear stability are confronted in the heaviest nuclei. How many more new elements can be synthesized? What are the nuclear and chemical properties of these exotic nuclei? Does the “Island of Stability” exist and can we ever explore the isotopes inhabiting that nuclear region? This paper will focus on the current experimental research on the synthesis and characterization of superheavy nuclei with Z>112 from the Dubna/Livermore collaboration. Reactions using 48Ca projectiles from the U400 cyclotron and actinide targets (233,238U, 237Np, 242,244Pu, 243Am, 245,248Cm, 249Cf) have been investigated using the Dubna Gas Filled Recoil Separator in Dubna over the last 8 years. In addition, several experiments have been performed to investigate the chemical properties of some of the observed longer-lived isotopes produced in these reactions. Some comments will be made on nuclear reactions used for the production of the heaviest elements. A summary of the current status of the upper end of the chart of nuclides will be presented. [ABSTRACT FROM AUTHOR]

The first results from the Stopped Beam RISING experimental campaign performed at the GSI laboratory in Darmstadt, Germany, are presented. RISING (Rare ISotope INvestigations at GSI) constitutes a major new experimental program in European nuclear structure physics research aimed at using relativistic-energy, projectile-fragmentation reactions to study nuclei with exotic proton-to-neutron ratios. This paper introduces the physics aims of the Stopped RISING collaboration and presents some technical details and initial results from experiments using the RISING array to study decays from metastable nuclear states in both proton and neutron-rich nuclei. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

High energy neutrino emission from GRBs is discussed. In this paper, by using the simulation kit GEANT4, we calculate proton cooling efficiency including pion-multiplicity and proton-inelasticity in photomeson production. First, we estimate the maximum energy of accelerated protons in GRBs. Using the obtained results, neutrino flux from one burst and a diffuse neutrino background are evaluated quantitatively. We also take account of cooling processes of pion and muon, which are crucial for resulting neutrino spectra. We confirm the validity of analytic approximate treatments on GRB fiducial parameter sets, but also find that the effects of multiplicity and high-inelasticity can be important on both proton cooling and resulting spectra in some cases. Finally, assuming that the GRB rate traces the star formation rate, we obtain a diffuse neutrino background spectrum from GRBs for specific parameter sets. We introduce the nonthermal baryon-loading factor, rather than assume that GRBs are main sources of UHECRs. We find that the obtained neutrino background can be comparable with the prediction of Waxman & Bahcall, although our ground in estimation is different from theirs. In this paper, we study on various parameters since there are many parameters in the model. The detection of high energy neutrinos from GRBs will be one of the strong evidences that protons are accelerated to very high energy in GRBs. Furthermore, the observations of a neutrino background has a possibility not only to test the internal shock model of GRBs but also to give us information about parameters in the model and whether GRBs are sources of UHECRs or not. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

In this paper we show how effective parameters such as effective binding energies can be defined for a proton in the combined nuclear-Coulomb potential, including also the target potential, in the case in which the proton is bound in a nucleus which is partner of a nuclear reaction. Using such effective parameters the proton behaves similarly to a neutron. In this way some unexpected results obtained from dynamical calculations for reactions initiated by very weakly bound proton halo nuclei can be interpreted. Namely the fact that stripping dominates the nuclear breakup cross section which in turn dominates over the Coulomb breakup even when the target is heavy at medium to high incident energies. Our interpretation helps also clarifying why the existence and characteristics of a proton halo extracted from different types of data have sometimes appeared contradictory. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

The discrepancy between the proton charge radius extracted from the muonic hydrogen Lamb shift measurement and the best present value obtained from the elastic scattering experiments, remains unexplained and represents a burning problem of today's nuclear physics: after more than 50 years of research the radius of a basic constituent of matter is still not understood. This paper presents a summary of the best existing proton radius measurements, followed by an overview of the possible explanations for the observed inconsistency between the hydrogen and the muonic-hydrogen data. In the last part the upcoming experiments, dedicated to remeasuring the proton radius, are described. [ABSTRACT FROM AUTHOR]

The LHCf experiment is a CERN experiment dedicated to forward physics which is optimized to measure the neutral particle flow at extreme pseudo-rapidity values, ranging from 8.4 up to infinity. LHCf results are extremely important for the calibration of the hadronic interaction models used for the study of the development of atmospheric showers in the Earth atmosphere. Starting from the recent run of proton- Lead nucleus interactions at LHC, the LHCf and ATLAS collaborations have performed a common data taking which allows a combined study of the central and forward regions of the interaction. The latest results of LHCf, the upgrade of the detectors for the next 6.5 TeV+ 6.5 TeV proton--proton run and the status of the LHCf-ATLAS common activities are summarized in this paper. [ABSTRACT FROM AUTHOR]

The Large Hadron Collider, designed to collide protons and ions at unprecedented center-of-mass energies, will offer new opportunities for the study of the properties of strongly interacting matter at high energy density and temperature. Such complex investigation will be carried out by three experiments, ALICE, explicitly dedicated to this purpose, ATLAS and CMS, through the analysis of several observables. Among them, an important role is expected to be played by heavy-flavor and heavy quarkonium state measurements. The motivations for measuring open and hidden charm and beauty will be provided in this paper, together with a discussion on the expected performances of the experiments, based on the results of Monte Carlo simulations for a selection of physics channels. [ABSTRACT FROM AUTHOR]

Charge-exchange reactions of (n, p) and (p, n) type at intermediate energies are a powerful tool for the study of nuclear matrix element in ββ decay. The present paper reviews some of the most recent experiments in this context. Here, the (n, p) type reactions are realized through (d, 2He), where 2He refers to two protons in a singlet 1S0 state and where both of these are momentum analyzed and detected by the same spectrometer and detector. These reactions have been developed and performed exclusively at KVI, Groningen (NL), using an incident deuteron energy of 183 MeV. Final state resolutions of about 100 keV have routinely been available. On the other hand, the (3He, t) reaction is of (p, n) type and was developed at the RCNP facility in Osaka (JP). Measurements with an unprecedented high resolution of 30 keV at incident energies of 420 MeV are now readily possible. Using both reaction types one can extract the Gamow-Teller transition strengths B(GT+) and B(GT-), which define the two “legs” of the ββ decay matrix elements for the 2vββ decay The high resolution available in both reactions allows a detailed insight into the excitations of the intermediate odd-odd nuclei and, as will be shown, some unexpected features are being unveiled. [ABSTRACT FROM AUTHOR]

We report on a study of exotic nuclei around doubly magic 132Sn in terms of the shell model employing a realistic effective interaction derived from the CD-Bonn nucleon-nucleon potential. The short-range repulsion of the latter is renormalized by constructing a smooth low-momentum potential, Vlow-k, that is used directly as input for the calculation of the effective interaction. In this paper, we focus attention on proton-neutron multiplets in the odd-odd nuclei 134Sb, 136Sb. We show that the behavior of these multiplets is quite similar to that of the analogous multiplets in the counterpart nuclei in the 208Pb region, 210Bi and 212Bi. [ABSTRACT FROM AUTHOR]

We use recently calculated next-to-next-to-leading order (NNLO) anomalous dimension coefficients for the moments of the F2 structure function in eN scattering, together with the corresponding two-loop Wilson coefficients, to obtain improved QCD predictions for non-singlet structure function. The Jacobi polynomial method is used to parameterize parton distribution up to NNLO. Target mass corrections is also consider in our calculations. [ABSTRACT FROM AUTHOR]

The Large Hadron Collider (LHC) at CERN will start running 2008 producing proton-proton collisions with a center-of-mass energy of 14 TeV. Four large experiments will operate together with this accelerator: ALICE, ATLAS, CMS and LHCb. The main scientific goal of this project is to understand in detail the mechanism for electro-weak symmetry breaking and to search for physics beyond the standard model of particles. ATLAS and CMS are general purpose detectors designed for search and discovery of new physics, and optimized to search for Higgs and signals of supersymmetric matter (SUSY). In this paper the main features of the CMS detector will be presented and its potential for Higgs and SUSY discoveries will be discussed. [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]

Super-Kamiokande is the world’s largest water Cherenkov detector, with a net mass of 50,000 tons. The scientific goals of the experiment include searches for proton decays, and studies of neutrinos from various sources. In this paper we review some of the latest results from our neutrino oscillations studies using atmospheric neutrinos, solar neutrinos and neutrinos from the KEK neutrino beam. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

The new FAIR facility which comes into operation at GSI in the upcoming years has a dedicated program of utilizing antiprotons for hadron physics. In particular, the planned PANDA experiment belongs to the group of core experiments at the new FAIR facility in Darmstadt/Germany. PANDA will be a universal detector to study the strong interaction by utilizing the annihilation process of antiprotons with protons and nuclear matter. The current paper gives an introduction into the hadron physics with antiprotons and part of the planned physics program with PANDA. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

In this paper we discuss the anti-GZK effect that arises in the framework of the diffusive propagation of Ultra High Energy (UHE) protons. This effect consists in a jump-like increase of the maximum distance from which UHE protons can reach the observer. The position of the jump is independent of the Intergalactic Magnetic Field (IMF) strength and depends only on the energy losses of protons, namely on the transition energy from adiabatic and pair-production energy losses. The Ultra High Energy Cosmic Rays (UHECR) spectrum presents a low-energy steepening approximately at this energy, which is very close to the position of the observed second knee. The dip, seen in the universal spectrum as a signature of the proton interaction with the Cosmic Microwave Background (CMB) radiation, is also present in the case of diffusive propagation in magnetic fields. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

Recent measurements of the proton structure function F2 and determination of the structure function FL in e+p deep inelastic scattering (DIS) by the H1 Collaboration are summarized. The F2 results presented here extend the previous measurements at HERA into the Q2 region below 1 GeV2 by also using Initial State Radiation (ISR) events. The FL structure function determined in the current analysis is more precise and accesses lower Q2 values as compared to previous determinations published by H1. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

High Power Proton Accelerators (HPPAs) are studied for several projects based on high-flux neutron sources driven by proton or deuteron beams. Since the front end is considered as the most critical part of such accelerators, the two French national research agencies CEA and CNRS decided to collaborate in 1997 to study and build a High-Intensity Proton Injector (IPHI). The main objective of this project is to master the complex technologies used and the concepts of manufacturing and controlling the HPPAs. Recently, a collaboration agreement was signed with CERN and led to some evolutions in the design and in the schedule. The IPHI design current was maintained at 100 mA in Continuous Wave mode. This choice should allow to produce a high reliability beam at reduced intensity (typically 30 mA) tending to fulfill the Accelerator Driven System requirements. The output energy of the Radio Frequency Quadrupole (RFQ), was reduced from 5 to 3 MeV, allowing then the adjunction and the test, in pulsed operation of a chopper line developed by CERN for the Superconducting Proton Linac (SPL). In a final step, the IPHI RFQ and the chopper line should become parts of the SPL injector. In this paper, the IPHI project and the recent evolutions are reported together with the construction and operation schedule. © 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]

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]

We present the core architecture of XIA‘s digital pulse processors and show how digital filtering and pile up inspection are performed in real time. XIA‘s pulse processors can simultaneously extract energy and pulse shape information from the detector pulses provided to its inputs. Two applications of this novel technology are discussed in the paper. High resolution for γ-rays was achieved at very short peaking times with digital ballistic deficit correction. Sequences of pulses characteristic of radioactive decay via proton emission can be recognized online with the real-time pileup inspector operated in the reversed logic mode [ABSTRACT FROM AUTHOR]

Beta-delayed proton emission was first observed thirty-six years ago. At the time, its unique signature opened a window onto a new world of exotic nuclei: on-line isotope separation was not yet available to isolate newly produced nuclei, but a readily separable decay mode was a fine alternative. In the first two decades after its discovery, beta-delayed proton decay was a rich source of spectroscopic information on nuclei far from stability, yielding everything from analog states and atomic masses to level densities and excited-state lifetimes in the femtosecond region. However, with the advent of more sophisticated methods for the production and isolation of exotic nuclei, the importance of beta-delayed protons as an identifier of new nuclei effectively disappeared. Nevertheless, the potential spectroscopic value of the process remains undiminished. In fact, as the number of known beta-decaying nuclei steadily increases, beta-delayed proton emission is seen to be a widely occurring phenomenon. Its usefulness needs to be rediscovered. This paper presents an overview of beta-delayed proton emission, its occurrence, its usefulness and its potential for the future [ABSTRACT FROM AUTHOR]