NSR Query Results
Output year order : Descending NSR database version of April 11, 2024. Search: Author = R.L.Helmer Found 29 matches. 2002TA22 Nucl.Instrum.Methods Phys.Res. A489, 178 (2002) N.J.Tagg, A.S.Hamer, B.Sur, E.D.Earle, R.L.Helmer, G.Jonkmans, B.A.Moffat, J.J.Simpson The 8Li Calibration Source for the Sudbury Neutrino Observatory RADIOACTIVITY 8Li(β-) [from 11B(n, α)]; measured Eβ, βα-coin. Use as calibration source in neutrino observatory discussed.
doi: 10.1016/S0168-9002(02)00860-4
2001PA45 Phys.Rev. C64, 064611 (2001) M.M.Pavan, J.T.Brack, F.Duncan, A.Feltham, G.Jones, J.Lange, K.J.Raywood, M.E.Sevior, R.Adams, D.F.Ottewell, G.R.Smith, B.Wells, R.L.Helmer, E.L.Mathie, R.Tacik, R.A.Ristinen, I.I.Strakovsky, H.-M.Staudenmaier Precision Pion-Proton Elastic Differential Cross Sections at Energies Spanning the Δ Resonance NUCLEAR REACTIONS 1H(π+, π+), (π-, π-), E=141.15-267.3 MeV; measured σ(θ), (pion)(proton)-coin. Comparison with model predictions.
doi: 10.1103/PhysRevC.64.064611
1998LO12 Phys.Rev. C57, 3191 (1998) S.A.Long, B.M.Spicer, K.J.Raywood, R.Abegg, W.P.Alford, A.Celler, D.Frekers, P.E.Green, O.Hausser, R.L.Helmer, R.S.Henderson, K.H.Hicks, K.P.Jackson, R.G.Jeppesen, N.S.P.King, C.A.Miller, M.A.Moinester, V.C.Officer, G.G.Shute, A.Trudel, M.C.Vetterli, A.I.Yavin, S.Yen Spin-Isovector Giant Resonances Induced by (n, p) Reactions on Heavy Nuclei NUCLEAR REACTIONS 120Sn, 181Ta(n, p), E=298 MeV; 238U(n, p), E=318 MeV; measured σ(Ep, θ). 90Zr, 208Pb(n, p), E=198 MeV; analyzed σ(Ep, θ). 90Y, 120In, 181Hf, 208Tl, 238Pa deduced L=0, 1, 2, 3 giant resonances energy distributions, quasi-free contributions, comparison with sum rules for L=1, 3. Multipole decomposition procedure.
doi: 10.1103/PhysRevC.57.3191
1997HE06 Phys.Rev. C55, 2802 (1997) R.L.Helmer, M.A.Punyasena, R.Abegg, W.P.Alford, A.Celler, S.El-Kateb, J.Engel, D.Frekers, R.S.Henderson, K.P.Jackson, S.Long, C.A.Miller, W.C.Olsen, B.M.Spicer, A.Trudel, M.C.Vetterli Gamow-Teller Strength from the 76Se(n, p)76As Reaction: Implications for the double β decay of 76Ge NUCLEAR REACTIONS 76Se(n, p), E=198 MeV; measured σ(θ). 76As deduced Gamow-Teller strength distribution. 76Ge deduced 2ν-accompanied 2β-decay T1/2. Quasi-particle RPA comparison, other data analyzed.
doi: 10.1103/PhysRevC.55.2802
1991HA01 Phys.Rev. C43, 230 (1991) O.Hausser, M.C.Vetterli, R.W.Fergerson, C.Glashausser, R.C.Jeppesen, R.D.Smith, R.Abegg, F.T.Baker, A.Celler, R.L.Helmer, R.Henderson, K.Hicks, M.J.Iqbal, K.P.Jackson, K.W.Jones, J.Lisantti, J.Mildenberger, C.A.Miller, R.S.Sawafta, S.Yen Nuclear Response in the 54Fe(p(pol), p(pol)') Reaction at 290 MeV NUCLEAR REACTIONS 54Fe(polarized p, p'), E=290 MeV; measured σ(θ), spin observables, analyzing power, spin-flip probabilities. 54Fe(n, p), E=298 MeV; analyzed data. 54Fe deduced isovector giant dipole, isoscalar giant quadrupole resonance. 54Mn deduced Gamow-Teller transition strength, quenching. Surface RPA model.
doi: 10.1103/PhysRevC.43.230
1990AL19 Nucl.Phys. A514, 49 (1990) W.P.Alford, R.L.Helmer, R.Abegg, A.Celler, D.Frekers, P.Green, O.Hausser, R.Henderson, K.Hicks, K.P.Jackson, R.Jeppesen, C.A.Miller, A.Trudel, M.Vetterli, S.Yen, R.Pourang, J.Watson, B.A.Brown, J.Engel Gamow-Teller Strength Observed in the 48Ti(n, p)48Sc Reaction: Implications for the double beta decay of 48Ca NUCLEAR REACTIONS 48Ti(n, p), E=198 MeV; measured σ(θ). 48Sc deduced Gamow-Teller strength distribution. Shell model comparison.
doi: 10.1016/0375-9474(90)90331-F
1990KO17 Phys.Rev. C41, 2571 (1990) R.G.Korteling, R.E.L.Green, J.M.D'Auria, R.L.Helmer, K.P.Jackson, S.B.Kaufman, B.D.Wilkins Light Fragment Emission as Studied by the (p, pHe) Reactions on Be and Ag with 300 MeV Protons NUCLEAR REACTIONS Be, Ag(p, pX), E=300 MeV; measured σ(Ep, θ), σ(E, fragment θ) for X=p, 3,4He; deduced differential mean multiplicities, invariant σ, rapidities.
doi: 10.1103/PhysRevC.41.2571
1990RA13 Phys.Rev. C41, 2836 (1990) K.J.Raywood, B.M.Spicer, S.Yen, S.A.Long, M.A.Moinester, R.Abegg, W.P.Alford, A.Celler, T.E.Drake, D.Frekers, P.E.Green, O.Hausser, R.L.Helmer, R.S.Henderson, K.H.Hicks, K.P.Jackson, R.G.Jeppesen, J.D.King, N.S.P.King, C.A.Miller, V.C.Officer, R.Schubank, G.G.Shute, M.Vetterli, J.Watson, A.I.Yavin Spin-Flip Isovector Giant Resonances from the 90Zr(n, p)90Y Reaction at 198 MeV NUCLEAR REACTIONS 90Zr(n, p), E=198 MeV; measured σ(Ep, θ); deduced σ(θ). 90Y deduced spin isovector dipole transition strengths.
doi: 10.1103/PhysRevC.41.2836
1989CE02 Phys.Lett. 227B, 336 (1989) D.A.Cebra, W.Benenson, Y.Chen, E.Kashy, A.Pradhan, A.Vander Molen, G.D.Westfall, W.K.Wilson, D.J.Morrissey, R.S.Tickle, R.Korteling, R.L.Helmer Two-Particle Correlations from 500 MeV p + Ag and Be NUCLEAR REACTIONS Ag, Be(p, 2pX), (p, 2dX), (p, dαX), (p, pdX), (p, pαX), (p, 2tX), E=500 MeV; measured light (particle)(particle)-correlations; deduced reaction mechanism.
doi: 10.1016/0370-2693(89)90940-4
1989HI10 Phys.Rev. C40, R2445 (1989) K.H.Hicks, M.C.Vetterli, A.Celler, R.L.Helmer, R.S.Henderson, K.P.Jackson, R.G.Jeppesen, A.Trudel, S.Yen Quasifree Analyzing Powers using the (p(pol), n) Reaction NUCLEAR REACTIONS 12C, 54Fe(polarized p, n), E=290, 420 MeV; measured σ(θn, En), analyzing power. Relativistic, nonrelativistic model analysis.
doi: 10.1103/PhysRevC.40.R2445
1989MO19 Phys.Lett. 230B, 41 (1989) M.A.Moinester, A.Trudel, K.Raywood, S.Yen, B.M.Spicer, R.Abegg, W.P.Alford, N.Auerbach, A.Celler, D.Frekers, O.Hausser, R.L.Helmer, R.Henderson, K.H.Hicks, K.P.Jackson, R.G.Jeppesen, N.S.P.King, S.Long, C.A.Miller, M.Vetterli, J.Watson, A.I.Yavin A Study of Spin Isovector Giant Resonances with the 208Pb(n, p)208Tl Reaction NUCLEAR REACTIONS 208Pb(n, p), E=198, 458 MeV; measured σ(θp, Ep). 208Tl deduced spin isovector giant resonances.
doi: 10.1016/0370-2693(89)91650-X
1988HA09 Phys.Rev. C37, 1119 (1988) O.Hausser, R.Sawafta, R.G.Jeppesen, R.Abegg, W.P.Alford, R.L.Helmer, R.Henderson, K.Hicks, K.P.Jackson, J.Lisantti, C.A.Miller, M.C.Vetterli, S.Yen Energy Dependence of Isovector and Isoscalar 1+ Excitations in 28Si(p, p') between 200 and 400 MeV NUCLEAR REACTIONS 28Si(p, p'), E=200-400 MeV; measured σ(θ). 28Si deduced isovector 1+ transition strengths, summed Gamow-Teller strengths.
doi: 10.1103/PhysRevC.37.1119
1988HA27 Phys.Rev.Lett. 61, 822 (1988) O.Hausser, R.Abegg, R.G.Jeppesen, R.Sawafta, A.Celler, A.Green, R.L.Helmer, R.Henderson, K.Hicks, K.P.Jackson, J.Mildenberger, C.A.Miller, M.C.Vetterli, S.Yen, M.J.Iqbal, R.D.Smith Complete Spin Observables for Quasielastic Proton Scattering from 54Fe at 290 MeV NUCLEAR REACTIONS 54Fe(polarized p, p'X), E=290 MeV; measured σ(θ, Ep'), spin-transfer σ(θ, Ep'), analyzing power, spin observables; deduced Fermi motion, nuclear response function, nucleon-nucleon interaction role. Relativistic, non-relativistic models, impulse approximation.
doi: 10.1103/PhysRevLett.61.822
1988HI03 Phys.Lett. 201B, 29 (1988) K.H.Hicks, O.Hausser, R.Abegg, W.P.Alford, A.Celler, R.L.Helmer, R.S.Henderson, K.P.Jackson, J.Lisantti, C.A.Miller, R.Sawafta, J.R.Shepard, S.Yen P-A(y) for Excitation of Natural- and Unnatural-Parity States of 12C by 400 MeV Protons NUCLEAR REACTIONS 12C(p, p'), E=400 MeV; measured polarization, analyzing power differences. Nonrelativistic, relativistic model calculations.
doi: 10.1016/0370-2693(88)90074-3
1988JA01 Phys.Lett. 201B, 25 (1988) K.P.Jackson, A.Celler, W.P.Alford, K.Raywood, R.Abegg, R.E.Azuma, C.K.Campbell, S.El-Kateb, D.Frekers, P.W.Green, O.Hausser, R.L.Helmer, R.S.Henderson, K.H.Hicks, R.Jeppesen, P.Lewis, C.A.Miller, A.Moalem, M.A.Moinester, R.B.Schubank, G.G.Shute, B.M.Spicer, M.C.Vetterli, A.I.Yavin, S.Yen The (n, p) Reaction as a Probe of Gamow-Teller Strength NUCLEAR REACTIONS 6Li, 12,13C(n, p), E=198 MeV; measured σ(θ), σ(θp).
doi: 10.1016/0370-2693(88)90073-1
1988YE01 Phys.Lett. 206B, 597 (1988) S.Yen, B.M.Spicer, M.A.Moinester, K.Raywood, R.Abegg, W.P.Alford, A.Celler, T.E.Drake, D.Frekers, O.Hausser, R.L.Helmer, R.S.Henderson, K.H.Hicks, K.P.Jackson, R.Jeppesen, J.D.King, N.S.P.King, K.Lin, S.Long, C.A.Miller, V.C.Officer, R.Schubank, G.G.Shute, M.C.Vetterli, A.I.Yavin Gamow-Teller Strength and Giant Resonances in 90Zr(n, p) at 198 MeV NUCLEAR REACTIONS 90Zr(n, p), E=198 MeV; measured σ(θp, Ep). 90Y deduced giant resonances, Gamow-Teller Strength.
doi: 10.1016/0370-2693(88)90703-4
1987FR05 Phys.Rev. C35, 2236 (1987) D.Frekers, S.S.M.Wong, R.E.Azuma, T.E.Drake, J.D.King, R.Abegg, K.P.Jackson, C.A.Miller, S.Yen, W.P.Alford, R.L.Helmer, C.Broude, S.Mattsson, E.Rost Elastic and Inelastic Scattering of 362 MeV polarized Protons from 40Ca NUCLEAR REACTIONS 40Ca(polarized p, p), (polarized p, p'), E=362 MeV; measured σ(θ), analyzing power. Magnetic spectrometer. Model calculations.
doi: 10.1103/PhysRevC.35.2236
1987GR11 Phys.Rev. C35, 1341 (1987) R.E.L.Green, R.G.Korteling, J.M.D'Auria, K.P.Jackson, R.L.Helmer Light Fragment Spectra to Upper Kinematic Limits for 300 MeV Proton Reactions with Be and Ag NUCLEAR REACTIONS 9Be, Ag(p, X), E=190, 300 MeV; measured σ(fragment θ, E) for X=2,1H, 3,4He, 6He, 6,7Li, 7Be; deduced slope parameters, source velocities, statistical model limits. Rapidity analysis.
doi: 10.1103/PhysRevC.35.1341
1987HA11 Phys.Lett. 184B, 316 (1987) O.Hausser, K.Hicks, C.W.Glover, R.Abegg, A.Celler, C.Gunther, R.L.Helmer, R.Henderson, D.J.Horen, C.J.Horowitz, K.P.Jackson, J.Lisantti, D.K.McDaniels, C.A.Miller, R.Sawafta, L.W.Swenson Spin Observables for 208Pb(p(pol), p(pol)) Elastic Scattering at 290 MeV NUCLEAR REACTIONS 208Pb(polarized p, p), E=290 MeV; measured polarizations, transfer coefficients vs momentum transfer; deduced elastic scattering amplitudes, spin rotation parameters. Focal-plane polarimeter. Dirac calculations.
doi: 10.1016/0370-2693(87)90172-9
1987HE24 Nucl.Instrum.Methods Phys.Res. A257, 97 (1987) R.S.Henderson, W.P.Alford, D.Frekers, O.Hausser, R.L.Helmer, K.H.Hicks, K.P.Jackson, C.A.Miller, M.C.Vetterli, S.Yen A Segmented Target Chamber for (n, p) Studies at TRIUMF NUCLEAR REACTIONS 7Li, 12C(n, p), E=198 MeV; measured σ(Ep), σ(θp). Segmented target chamber.
doi: 10.1016/0168-9002(87)90728-5
1987MO04 Phys.Lett. 183B, 269 (1987) A.Moalem, D.Frekers, S.A.Gurvitz, R.Abegg, C.Davis, K.P.Jackson, C.A.Miller, R.S.Henderson, S.Yen, R.L.Helmer, K.H.Hicks, J.S.Wesick Inclusive Analyzing Power and Scattering Mechanisms in Proton-Nucleus Scattering at Backward Angles NUCLEAR REACTIONS 9Be, C(polarized p, p'), E=303 MeV; measured analyzing power (θ=120°); deduced scattering mechanism. ΔE-E telescopes.
doi: 10.1016/0370-2693(87)90961-0
1986AL18 Phys.Lett. 179B, 20 (1986) W.P.Alford, R.L.Helmer, R.Abegg, A.Celler, O.Hausser, K.Hicks, K.P.Jackson, C.A.Miller, S.Yen, R.E.Azuma, D.Frekers, R.S.Henderson, H.Baer, C.D.Zafiratos Ratio of the Isovector Effective Interaction Strengths (J(στ)/J(τ))2 between 200 and 450 MeV from the 14C(p, n)14N Reaction NUCLEAR REACTIONS 14C(p, n), E=200, 300, 400, 450 MeV; measured σ(θ); deduced ratios of distortion factors, isovector effective interaction strengths. 14N levels deduced Gamow-Teller, Fermi transition σ ratio. DWIA.
doi: 10.1016/0370-2693(86)90428-4
1986KH01 Can.J.Phys. 64, 219 (1986) M.Khaliquzzaman, W.K.Dawson, H.W.Fielding, P.W.Green, R.L.Helmer, W.J.McDonald, G.C.Neilson, B.C.Robertson, D.M.Sheppard Energy Levels, Decay Scheme, Gamma-Ray Branching Ratios, and Lifetimes in 49V with (p, nγ) Reaction NUCLEAR REACTIONS 49Ti(p, nγ), E=5.74 MeV; measured Eγ, Iγ, γ(t). 49V deduced levels, γ-branching, J, π, T1/2.
doi: 10.1139/p86-040
1985LA13 Phys.Rev. C32, 76 (1985) S.T.Lam, W.K.Dawson, S.A.Elbakr, H.W.Fielding, P.W.Green, R.L.Helmer, I.J.van Heerden, A.H.Hussein, S.P.Kwan, G.C.Neilson, T.Otsubo, D.M.Sheppard, H.S.Sherif, J.Soukup Elastic Scattering of Polarized Neutrons on 16O, 59Co, and Pb at 23 MeV NUCLEAR REACTIONS 16O, 59Co, Pb(polarized n, n), E=23 MeV; measured σ(θ), A(θ). Optical model potential analysis.
doi: 10.1103/PhysRevC.32.76
1984HE03 Phys.Rev. C29, 676 (1984) R.L.Helmer, R.E.L.Green, K.P.Jackson, R.G.Korteling Wide Angle Deuteron Emission in the 9Be(p, pd) Reaction at 300 MeV Mimics (p, 2p) Systematics NUCLEAR REACTIONS 9Be(p, pd), E=300 MeV; measured inclusive integrated σ(θp, Ep), pd(θ); deduced differential multiplicities < Mp >.
doi: 10.1103/PhysRevC.29.676
1984KH04 Nucl.Phys. A424, 191 (1984) M.Khaliquzzaman, W.K.Dawson, H.W.Fielding, P.W.Green, R.L.Helmer, W.J.McDonald, G.C.Neilson, B.C.Robertson, D.M.Sheppard Energy Levels, Decay Scheme, γ-Ray Branching Ratios and Lifetimes in 55Fe from the 55Mn(p, nγ)55Fe Reaction NUCLEAR REACTIONS 55Mn(p, nγ), E=4, 6 MeV; measured Eγ, Iγ, γ-time distribution. 55Fe deduced levels, decay scheme, γ-branching, T1/2. Natural targets.
doi: 10.1016/0375-9474(84)90181-7
1983GR21 Nucl.Phys. A405, 463 (1983) R.E.L.Green, D.H.Boal, R.L.Helmer, K.P.Jackson, R.G.Korteling Large-Angle Proton Emission in the 9Be(p, 2p) Reaction at 300 MeV NUCLEAR REACTIONS Be(p, pX), (p, 2pX), E=300 MeV; measured σ(E(p), θ(p)), σ(E1, θ1, E2, θ2=90°), pp-coin. Comparison with phase-space, direct knockout calculations.
doi: 10.1016/0375-9474(83)90515-8
1980HE04 Nucl.Phys. A336, 219 (1980) R.L.Helmer, M.D.Hasinoff, J.E.Bussoletti, K.A.Snover, T.A.Trainor Investigation of the Electric Quadrupole Strength in 13N Using the 12C(p, γ0)13N Reaction NUCLEAR REACTIONS 12C(polarized p, γ), E=10-17 MeV; measured σ(Ep, θγ), asymmetry. 13N deduced E1, E2 σ. Enriched target.
doi: 10.1016/0375-9474(80)90621-1
1970BA68 Can.J.Phys. 48, 3059 (1970) G.M.Bailey, G.M.Griffiths, M.A.Olivo, R.L.Helmer Gamma-Ray Yields from the Reaction D(p, γ)3He at Low Energies NUCLEAR REACTIONS 2H(p, γ), E=0.6-1.2 MeV; measured σ(E;Eγ).
doi: 10.1139/p70-379
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