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Explosive hydrogen burning during type I X-ray bursts

Description: Explosive hydrogen burning in type I X-ray bursts (XRBs) is driven by charged particle reactions creating isotopes with masses up to A {approx} 100. Since charged particle reactions in a stellar environment are very temperature sensitive, we use a realistic time-dependent general relativistic and self-consistent model of type I X-ray bursts to provide accurate values of the burst temperatures and densities. This allows a detailed and accurate time-dependent identification of the reaction flow from the surface layers through the convective region and the ignition region to the neutron star ocean. Using this, we determine the relative importance of specific nuclear reactions in the X-ray burst.
Date: June 11, 2007
Creator: Fisker, J L; Schatz, H & Thielemann, F
Partner: UNT Libraries Government Documents Department

Assessment of the current status of basic nuclear data compilations

Description: The Panel on Basic Nuclear Data Compilations met on April 6, 1979, to review the present status of nuclear data compilations. The following topics are addressed in this report: A-chain situation; ENSDF, Nuclear Structure Reference Files, and Recent References; Handbook of the Nuclides; and charged particle nuclear data. The panel made 13 recommendations, probably the most forceful being its recommendation against the use of data from unreferenced journals in ENSDF. 1 table. (RWR)
Date: January 1, 1979
Partner: UNT Libraries Government Documents Department

Nuclear chemistry progress report. [Summary of research at the University of Maryland]

Description: The present progress report attempts to summarize the research results obtained from the nuclear reactions aspect of the nuclear chemistry research program at the University of Maryland. The principal areas of investigation summarized in the present report deal primarily with reaction mechanism studies in heavy-ion-induced nuclear reactions and the study of nuclear reactions of astro physical significance.
Date: September 1, 1977
Creator: Viola, V.E. Jr.
Partner: UNT Libraries Government Documents Department

Integral charged particle nuclear date bibliography. Editon 1, Supplement 2

Description: This bibliography is divided into three sections, ''References'', ''Target Index'', and ''Residual Index.'' The ''References'' section contains all references satisfying the following criteria: excitation functions, thick targets, or product yield leading to the formation of a ground or metastable state; the atomic mass and charge of the incident particle must be greater than or equal to 1; the atomic mass of the target must be greater than or equal to 1; and the atomic masses of the outgoing and residual nuclei must be greater than or equal to 1 with the exception of processes which do not lead to a definite residual nucleus and of gamma-ray production cross sections. The ''Target Index'' section contains the incident particle energy and the abbreviated reference lines for all the entries, which contain information on a definite target nucleus and reaction. These reference lines contain the Journal name, followed by the volume and page number. The ''Residual Index'' section also contains the incident particle energy and the abbreviated reference lines for all the entries, which contain information on a definite residual nucleus and a definite target-reaction.
Date: April 1, 1986
Creator: Holden, N.E.; Ramavataram, S. & Dunford, C.L.
Partner: UNT Libraries Government Documents Department

Nuclear chemistry progress report. [Dept. of Chemistry and Cyclotron Lab. , Univ. of Maryland, College Park, August 1, 1978 to July 31, 1979]

Description: Research activities during the period August 1, 1978 to July 31, 1979 are summarized. The major effort has continued to be devoted to the study of nucleon exchange and energy dissipation mechanisms in damped heavy-ion reactions. Among the most significant accomplishments of the program during the past year has been the measurement of damped fragment spectra with discrete Z and A resolution. These studies provided detailed information on the A/Z equilibration and nucleon exchange processes in damped heavy-ion collisions, gave evidence for structure in the partially damped energy spectra for the Fe + Fe reaction, showed the importance of target-projectile mass asymmetry in governing the evolution of damped reactions, and gave tentative evidence for several new isotopes in the Z = 22 to 26 range. Other experiments utilized the fission-fragment angular correlation technique to determine the linear momentum transfer from projectile to target for /sup 16/O reactions in the 8- to 20-MeV/u region and to study simultaneously light-ion spectra (Z = 1 to 8) in coincidence with correlated events. These studies provided a much clearer picture of properties of central and peripheral collisions in heavy-ion reactions, as well as the transition between these two extremes. In addition, problems of Li, Be, and B nucleosynthesis and the relationship of these results to the question of the expanding universe were investigated. Individual sections with significant amounts of information are abstracted separately. (RWR)
Date: August 1, 1979
Creator: Viola, V.E. Jr.
Partner: UNT Libraries Government Documents Department

Proceedings of the international conference on nuclear physics, August 24-30, 1980, Berkeley, California. Volume 1. Abstracts. [Berkeley, California, August 24-30, 1980 (abstracts only)]

Description: This volume contains all abstracts (931) received by the conference organizers before June 20, 1980. The abstracts are grouped according to the following topics: nucleon-nucleon interactions, free and in nuclei; distribution of matter, charge, and magnetism; exotic nuclei and exotic probes; giant resonances and other high-lying excitations; applications of nuclear science; nuclei with large angular momentum and deformation; heavy-ion reactions and relaxation phenomena; new techniques and instruments; pion absorption and scattering by nuclei; and miscellaneous. Some of these one-page abstracts contain data. A complete author index is provided. (RWR)
Date: January 1, 1980
Partner: UNT Libraries Government Documents Department

Integral charged particle nuclear data bibliography: Literature scanned from April 1, 1986 through April 10, 1987

Description: This bibliography is divided into three sections, ''References,'' ''Target Index,'' and ''Residual Index.'' The ''References'' section contains all references satisfying the following criteria: excitation functions, thick targets, or product yield leading to the formation of a ground or metastable state; the atomic mass and charge of the incident particle must be greater than or equal to1; the atomic mass of the target must be greater than or equal to1; and the atomic masses of the outgoing and residual nuclei must be greater than or equal to1 with the exception of processes which do not lead to a definite residual nucleus and of gamma-ray production cross sections. The ''Target Index'' section contains the incident particle energy and the abbreviated reference lines for all the entries, which contain information on a definite target nucleus and reaction. These reference lines contain the Journal name, followed by the volume and page number. The ''Residual Index'' section also contains the incident particle energy and the abbreviated reference lines for all the entries, which contain information on a definite residual nucleus and a definite target-reaction.
Date: April 1, 1987
Creator: Holden, N.E.; Ramavataram, S. & Dunford, C.L.
Partner: UNT Libraries Government Documents Department

Nuclear physics in the 10 to 300 MeV energy range using a pulsed white neutron source

Description: A new pulsed white neutron source is under construction at the Los Alamos WNR facility. The neutrons are produced by LAMPF proton micropulses striking thick targets of various materials. Beam parameters include energy of 800 MeV, pulse rate of approximately 50,000 Hz, 0.4 nsec pulse width, average current as high as 6..mu..a, and a useful neutron energy range from 3 to 300 MeV. The facility will receive beam approximately 80% of the time LAMPF is operational; it increased by a factor of 1000 the experimental capability over the present system at the WNR when beam intensity, angular distribution, and availability are taken into account. In addition to established white source techniques, the facility is also highly competitive with monoenergetic sources for a wide class of experiments such as neutron capture ..gamma.. ray spectroscopy and neutron-induced charged particle reactions. The facility should be operational in about nine months. Arrangements are underway to make the facility readily accessible to visiting experimenters.
Date: January 1, 1984
Creator: Bowman, C.D.; Wender, S.A. & Auchampaugh, G.F.
Partner: UNT Libraries Government Documents Department

Investigations of nuclear structure and nuclear reactions induced by complex projectiles. Technical progress report, November 1, 1977--October 31, 1978. [Dept. of Chemistry, Washington Univ. , St. Louis]

Description: Work in progress or completed during the last two contract years is summarized first. Often the summary is a photocopy of the first page of a published article, but longer reports are also included. General areas of interest are fusion reactions, strongly damped heavy-ion collisions, and nuclear structure at high angular momentum. Then the present status of instrumentation and analysis is reviewed; apparatus for ..gamma..-ray and particle multiplicity experiments, a magnetic lends--Si(Li) versatile conversion electron spectrometer, a total-energy or coincidence-summing spectrometer, detection equipment, and data acquisition and reduction are discussed. Lists of publications and scientific and technical personnel complete the report. 19 figures, 2 tables. (RWR)
Date: January 1, 1978
Creator: Sarantites, D.G.
Partner: UNT Libraries Government Documents Department

Summary talk at the symposium on relativistic heavy ion research G. S. I. , Darmstadt, Germany. [Darmstadt, March 1978]

Description: Ideas expressed at the symposium and the general state of relativistic heavy-ion research are reviewed. The relationship with biology and medicine and with fusion is addressed. What has been learned about heavy ions and suggested possible next research steps are tabulated. 3 figures, 4 tables. (RWR)
Date: March 1, 1978
Creator: Grunder, H.A.
Partner: UNT Libraries Government Documents Department

The Argonne Fragment Mass Analyzer

Description: The Fragment Mass Analyzer is being constructed for use in heavy-ion experiments with the ATLAS superconducting linear accelerator system at Argonne National Laboratory. It is a triple-focussing recoil mass spectrometer, designed to separate nuclear reaction recoils from the primary heavy-ion beam and disperse them in M/Q (mass/unit charge) at the focal plane. The main ion-optical elements are two electric dipoles and a magnetic dipole, with the electric dipoles (E) symmetrically placed before and after the magnet (M). The elements are spaced such that the position energy dispersion (x/delta/sub E/) and the angle energy dispersion (theta/delta/sub E/) of the system both vanish (energy focus). Here delta/sub E/ stands for ..delta..E/E, the fractional energy deviation from the central energy. The energy-dispersionless EME configuration was first used by Cormier and Stwertka for the Recoil Mass Spectrometers at Rochester, and was also chosen by Spolaore et al. for the Recoil Mass Spectrometer at the Laboratori Nazionali di Legnaro in Padua. Although the energy dispersion is canceled, the M/Q dispersion is not, and the device performs as a mass spectrometer. When used in the energy-dispersionless mode, the EME combination of elements offers some distinct advantages over designs containing Wien filters or a single electrostatic element. These advantages include wider M/Q and energy acceptances and superior rejection of the primary beam (/approximately/10/sup /minus/12/). The energy focus condition implies isochronous orbits for particles having the same M/Q and energy but with differing emission angles at the target, an important feature when used with pulsed beam accelerators like ATLAS. 8 refs., 4 figs., 1 tab.
Date: January 1, 1988
Creator: Davids, C.N. & Larson, J.D.
Partner: UNT Libraries Government Documents Department

Comments on the current status and possible future directions of research on heavy-ion interactions near the Coulomb barrier

Description: This paper contains comments on the current status and possible future directions of research on heavy-ion interactions near the Coulomb barrier. Fusion reactions, elastic and inelastic scattering and transfer reactions are discussed. (LSP)
Date: January 1, 1990
Creator: Satchler, G.R.
Partner: UNT Libraries Government Documents Department

Some thoughts on opportunities with reactions using radioactive beams

Description: I was asked to talk about the use of radioactive beams for nuclear reactions. My overall perspective is that the scientific justification for such studies must be done carefully. To go to the added complexity of radioactive beams one must clearly demonstrate the need for obtaining information about nuclear structure or processes, information that is not otherwise available. On the other hand, much of what we know about nuclear structure comes from nuclear reactions with stable nuclear beams and targets. While a certain amount of information about far from stability nuclei may be obtained from the study of their radioactive decays, this is limited. Our knowledge and understanding of nuclear structure comes from stable nuclei: energy levels, their spins and parties, and very importantly the matrix elements characterizing them. These are largely determined by reaction studies with normal stable nuclei. The extension of such studies to unstable nuclei, far from stability, may well hold qualitative surprises, or at the very least give a firmer basis to our understanding of nuclear structure. Perhaps it is a matter of taste, but if one wishes to start on this endeavor then it is best to begin with simple, easily accessible features. The simplest'' nuclei are the ones that form doubly-closed shells and the easiest features to explore initially are the single-particle states and the collective excitations that one can build on these. I would like to emphasize that a unique facility for this type of study is about to come into operation in Darmstadt where the ESR storage ring will capture radioactive beams from fragmentation products and cool them to useful energies for reaction studies.
Date: January 1, 1990
Creator: Schiffer, J.P. (Argonne National Lab., IL (USA) Chicago Univ., IL (USA))
Partner: UNT Libraries Government Documents Department

Charge exchange probes of nuclear structure and interactions with emphasis on (p,n)

Description: New results from (p,n) studies at IUCF show that it is possible to observe Gamow-Teller (GT) strength and extract GT matrix elements from (p,n) measurements. The charge exchange reactions (/sup 6/Li,/sup 6/He) and (..pi../sup +/,..pi../sup 0/) involve different projectile quantum numbers, and the relationships of these reactions to (p,n) is discussed.
Date: January 1, 1980
Creator: Goodman, C.D.
Partner: UNT Libraries Government Documents Department

Can antibaryons signal the formation of a quark-gluon plasma

Description: We report on recent work which indicates that an enhancement of antibaryons produced in the hadronization phase transition can signal the existence of a transient quark-gluon plasma phase formed in a heavy-ion collision. The basis of the enhancement mechanism is the realization that antiquark densities are typically a factor 3 higher in the quark-gluon plasma phase than in hadronic matter at the same temperature and baryon density. The signal is improved by studying larger clusters of antimatter, i.e., light antinuclei like anti ..cap alpha.., in the central rapidity region. The effects of the transition dynamics and of the first order nature of the phase transition on the hadronization process are discussed.
Date: January 1, 1985
Creator: Heinz, U.; Subramanian, P.R. & Greiner, W.
Partner: UNT Libraries Government Documents Department

High energy nuclear collisions: physics perspectives

Description: The main aim of relativistic heavy ion experiments is to study the states of matter in strong interaction physics. We survey the predictions which statistical QCD makes for deconfinement and the transition to the quark-gluon plasma. 10 refs., 6 figs.
Date: January 1, 1985
Creator: Satz, H.
Partner: UNT Libraries Government Documents Department

1985 bibliography of atomic and molecular processes

Description: This annotated bibliography includes papers on atomic and molecular processes published during 1985. Sources include scientific journals, conference proceedings, and books. Each entry is designated by one or more of the 114 categories of atomic and molecular processes used by the Controlled Fusion Atomic Data Center, Oak Ridge National Laboratory to classify data. Also indicated is whether the work was experimental or theoretical, what energy range was covered, what reactants were investigated, and the country of origin of the first author. Following the bibliographical listing, the entries are indexed according to the categories and according to reactants within each subcategory.
Date: June 1, 1986
Creator: Barnett, C.F.; Gilbody, H.B.; Gregory, D.C.; Griffin, P.M.; Havener, C.C.; Howald, A.M. et al.
Partner: UNT Libraries Government Documents Department

Fully stripped heavy ion yield vs energy for Xe and Au ions

Description: The Bevalac is now capable of accelerating U-238 ions to approximately 1 GeV/amu and measurements have shown that fully stripped U-238 ions are produced with good yield at these energies. However, knowing the stripping yields at different energies for U-238 does not allow an accurate prediction for other, lower Z projectiles. Consequently, extensive stripping yield measurements were made for Au-197 and Xe-139 ions. In addition to the stripping measurements from the direct Bevalac beam, pickup measurements were also made with specially prepared bare, one electron, and two electron ions. Since many research groups are considering heavy ion storage rings and/or synchrotrons, the pickup cross section for bare ions is important to estimate beam lifetime in terms of the average machine vacuum. Since the Mylar target provides a pickup probability similar to air, a preliminary analysis of the Xe/sup 54 +/ and U/sup 92 +/ data are presented along with predictions for other ions ranging down to Fe/sup 26 +/. 11 refs., 3 figs., 1 tab.
Date: January 1, 1985
Creator: Thieberger, P.; Wegner, H.E.; Alonzo, J.; Gould, H.; Anholt, R.E. & Meyerhof, W.E.
Partner: UNT Libraries Government Documents Department

Nuclear structure theory. Annual technical progress report, October 1, 1976--September 30, 1977. [Research progress at the University of Rochester]

Description: This report summarizes progress during the past year in the following areas of nuclear structure and reaction theory: (1) statistical spectroscopy, including giant resonances for beta and electromagnetic excitation and sum rules (including inverse-energy-weighted sum rules), statistical methods of truncating shell model spaces and renormalization of operators, study of state labelling and ''chains'' of groups, evaluation of fluctuation measures, technical aspects of operator averaging; (2) meson interactions with nuclei, including scattering and absorption of mesons by nuclei (general methods), models for absorption, single- and double-charge exchange of pions, role of rho mesons.
Date: January 1, 1977
Creator: French, J.B. & Koltun, D.S.
Partner: UNT Libraries Government Documents Department

Theory of heavy ion collisions. Annual progress report

Description: It is demonstrated clearly that macroscopic models account for many of the observed features of heavy ion collisions. During this phase of the program major steps have been taken toward a better understanding of fusion excitation function, strongly damped collisions, the emission of nucleons at intermediate energies, heavy ion collisions and pions in relativistic heavy ion collisions.
Date: August 1, 1980
Creator: Sperber, D.
Partner: UNT Libraries Government Documents Department