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Lotay G, Lennarz A, Ruiz C, Akers C, Chen AA, Christian G, Connolly D, Davids B, Davinson T, Fallis J, Hutcheon DA, Machule P, Martin L, Mountford DJ, Murphy ASJ. Radiative Capture on Nuclear Isomers: Direct Measurement of the ^{26m}Al(p,γ)^{27}Si Reaction. Phys Rev Lett 2022; 128:042701. [PMID: 35148128 DOI: 10.1103/physrevlett.128.042701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 12/10/2021] [Accepted: 12/24/2021] [Indexed: 06/14/2023]
Abstract
We present the first direct measurement of an astrophysical reaction using a radioactive beam of isomeric nuclei. In particular, we have measured the strength of the key 447-keV resonance in the ^{26m}Al(p,γ)^{27}Si reaction to be 432_{-226}^{+146} meV and find that this resonance dominates the thermally averaged reaction rate for temperatures between 0.3 and 2.5 GK. This work represents a critical development in resolving one of the longest standing issues in nuclear astrophysics research, relating to the measurement of proton capture reactions on excited quantum levels, and offers unique insight into the destruction of isomeric ^{26}Al in astrophysical plasmas.
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Affiliation(s)
- G Lotay
- Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom
| | - A Lennarz
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
- Department of Physics and Astronomy, McMaster University, Hamilton, Ontario L8S 4M1, Canada
| | - C Ruiz
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
- Department of Physics and Astronomy, University of Victoria, Victoria, BC V8W 2Y2, Canada
| | - C Akers
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
- Department of Physics, University of York, Heslington, York YO10 5DD, United Kingdom
| | - A A Chen
- Department of Physics and Astronomy, McMaster University, Hamilton, Ontario L8S 4M1, Canada
| | - G Christian
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - D Connolly
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - B Davids
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
- Department of Physics, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - T Davinson
- School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | - J Fallis
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - D A Hutcheon
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - P Machule
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - L Martin
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - D J Mountford
- School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
| | - A St J Murphy
- School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
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Wilkinson R, Lotay G, Lennarz A, Ruiz C, Christian G, Akers C, Catford WN, Chen AA, Connolly D, Davids B, Hutcheon DA, Jedrejcic D, Laird AM, Martin L, McNeice E, Riley J, Williams M. Direct Measurement of the Key E_{c.m.}=456 keV Resonance in the Astrophysical ^{19}Ne(p,γ)^{20}Na Reaction and Its Relevance for Explosive Binary Systems. Phys Rev Lett 2017; 119:242701. [PMID: 29286739 DOI: 10.1103/physrevlett.119.242701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Indexed: 06/07/2023]
Abstract
We have performed a direct measurement of the ^{19}Ne(p,γ)^{20}Na reaction in inverse kinematics using a beam of radioactive ^{19}Ne. The key astrophysical resonance in the ^{19}Ne+p system has been definitely measured for the first time at E_{c.m.}=456_{-2}^{+5} keV with an associated strength of 17_{-5}^{+7} meV. The present results are in agreement with resonance strength upper limits set by previous direct measurements, as well as resonance energies inferred from precision (^{3}He, t) charge exchange reactions. However, both the energy and strength of the 456 keV resonance disagree with a recent indirect study of the ^{19}Ne(d, n)^{20}Na reaction. In particular, the new ^{19}Ne(p,γ)^{20}Na reaction rate is found to be factors of ∼8 and ∼5 lower than the most recent evaluation over the temperature range of oxygen-neon novae and astrophysical x-ray bursts, respectively. Nevertheless, we find that the ^{19}Ne(p,γ)^{20}Na reaction is likely to proceed fast enough to significantly reduce the flux of ^{19}F in nova ejecta and does not create a bottleneck in the breakout from the hot CNO cycles into the rp process.
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Affiliation(s)
- R Wilkinson
- Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom
| | - G Lotay
- Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom
- National Physical Laboratory, Teddington, Middlesex TW11 0LW, United Kingdom
| | - A Lennarz
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - C Ruiz
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - G Christian
- Cyclotron Institute, Texas A&M University, College Station, Texas 77843-3366, USA
- Department of Physics and Astronomy, Texas A&M University, College Station, Texas 77843-3366, USA
- Nuclear Solutions Institute, Texas A&M University, College Station, Texas 77843-3366, USA
| | - C Akers
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - W N Catford
- Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom
| | - A A Chen
- Department of Physics and Astronomy, McMaster University, Hamilton, Ontario L8S 4M1, Canada
| | - D Connolly
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - B Davids
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - D A Hutcheon
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - D Jedrejcic
- Colorado School of Mines, Golden, Colorado 80401, USA
| | - A M Laird
- Department of Physics, The University of York, York YO10 5DD, United Kingdom
| | - L Martin
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - E McNeice
- Department of Physics and Astronomy, McMaster University, Hamilton, Ontario L8S 4M1, Canada
| | - J Riley
- Department of Physics, The University of York, York YO10 5DD, United Kingdom
| | - M Williams
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
- Department of Physics, The University of York, York YO10 5DD, United Kingdom
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Kumar A, Kanungo R, Calci A, Navrátil P, Sanetullaev A, Alcorta M, Bildstein V, Christian G, Davids B, Dohet-Eraly J, Fallis J, Gallant AT, Hackman G, Hadinia B, Hupin G, Ishimoto S, Krücken R, Laffoley AT, Lighthall J, Miller D, Quaglioni S, Randhawa JS, Rand ET, Rojas A, Roth R, Shotter A, Tanaka J, Tanihata I, Unsworth C. Nuclear Force Imprints Revealed on the Elastic Scattering of Protons with ^{10}C. Phys Rev Lett 2017; 118:262502. [PMID: 28707906 DOI: 10.1103/physrevlett.118.262502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Indexed: 06/07/2023]
Abstract
How does nature hold together protons and neutrons to form the wide variety of complex nuclei in the Universe? Describing many-nucleon systems from the fundamental theory of quantum chromodynamics has been the greatest challenge in answering this question. The chiral effective field theory description of the nuclear force now makes this possible but requires certain parameters that are not uniquely determined. Defining the nuclear force needs identification of observables sensitive to the different parametrizations. From a measurement of proton elastic scattering on ^{10}C at TRIUMF and ab initio nuclear reaction calculations, we show that the shape and magnitude of the measured differential cross section is strongly sensitive to the nuclear force prescription.
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Affiliation(s)
- A Kumar
- Astronomy and Physics Department, Saint Mary's University, Halifax, Nova Scotia B3H 3C3, Canada
| | - R Kanungo
- Astronomy and Physics Department, Saint Mary's University, Halifax, Nova Scotia B3H 3C3, Canada
| | - A Calci
- TRIUMF, Vancouver, British Columbia V6T2A3, Canada
| | - P Navrátil
- TRIUMF, Vancouver, British Columbia V6T2A3, Canada
| | - A Sanetullaev
- Astronomy and Physics Department, Saint Mary's University, Halifax, Nova Scotia B3H 3C3, Canada
- TRIUMF, Vancouver, British Columbia V6T2A3, Canada
| | - M Alcorta
- TRIUMF, Vancouver, British Columbia V6T2A3, Canada
| | - V Bildstein
- Department of Physics, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - G Christian
- TRIUMF, Vancouver, British Columbia V6T2A3, Canada
| | - B Davids
- TRIUMF, Vancouver, British Columbia V6T2A3, Canada
| | - J Dohet-Eraly
- TRIUMF, Vancouver, British Columbia V6T2A3, Canada
- Istituto Nazionale di Fisica Nucleare, Sezione di Pisa, Largo B. Pontecorvo 3, I-56127 Pisa, Italy
| | - J Fallis
- TRIUMF, Vancouver, British Columbia V6T2A3, Canada
| | - A T Gallant
- TRIUMF, Vancouver, British Columbia V6T2A3, Canada
| | - G Hackman
- TRIUMF, Vancouver, British Columbia V6T2A3, Canada
| | - B Hadinia
- Department of Physics, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - G Hupin
- Institut de Physique Nucléaire, Université Paris-Sud, IN2P3/CNRS, F-91406 Orsay Cedex, France
- CEA, DAM, DIF, F-91297 Arpajon, France
| | - S Ishimoto
- High Energy Accelerator Research Organization (KEK), Ibaraki 305-0801, Japan
| | - R Krücken
- TRIUMF, Vancouver, British Columbia V6T2A3, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - A T Laffoley
- Department of Physics, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - J Lighthall
- TRIUMF, Vancouver, British Columbia V6T2A3, Canada
| | - D Miller
- TRIUMF, Vancouver, British Columbia V6T2A3, Canada
| | - S Quaglioni
- Lawrence Livermore National Laboratory, P.O. Box 808, L-414, Livermore, California 94551, USA
| | - J S Randhawa
- Astronomy and Physics Department, Saint Mary's University, Halifax, Nova Scotia B3H 3C3, Canada
| | - E T Rand
- Department of Physics, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - A Rojas
- TRIUMF, Vancouver, British Columbia V6T2A3, Canada
| | - R Roth
- Institut fur Kernphysik, Technische Universitat Darmstadt, 64289 Darmstadt, Germany
| | - A Shotter
- School of Physics and Astronomy, University of Edinburgh, JCMB, Mayfield Road, Edinburgh EH9 3JZ, United Kingdom
| | - J Tanaka
- RCNP, Osaka University, Mihogaoka, Ibaraki, Osaka 567 0047, Japan
| | - I Tanihata
- RCNP, Osaka University, Mihogaoka, Ibaraki, Osaka 567 0047, Japan
- School of Physics and Nuclear Energy Engineering and IRCNPC, Beihang University, Beijing 100191, China
| | - C Unsworth
- TRIUMF, Vancouver, British Columbia V6T2A3, Canada
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Wilkinson R, Lotay G, Lennarz A, Ruiz C, Christian G, Akers C, Catford WN, Chen AA, Connolly D, Davids B, Hutcheon DA, Jedrejcic D, Laird AM, Martin L, McNeice E, Riley J, Williams M. Constraining the 19Ne(p,γ) 20Na Reaction Rate Using a Direct Measurement at DRAGON. EPJ Web Conf 2017. [DOI: 10.1051/epjconf/201716501054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Lotay G, Christian G, Ruiz C, Akers C, Burke DS, Catford WN, Chen AA, Connolly D, Davids B, Fallis J, Hager U, Hutcheon DA, Mahl A, Rojas A, Sun X. Direct Measurement of the Astrophysical ^{38}K(p,γ)^{39}Ca Reaction and Its Influence on the Production of Nuclides toward the End Point of Nova Nucleosynthesis. Phys Rev Lett 2016; 116:132701. [PMID: 27081974 DOI: 10.1103/physrevlett.116.132701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Indexed: 06/05/2023]
Abstract
We have performed the first direct measurement of the ^{38}K(p,γ)^{39}Ca reaction using a beam of radioactive ^{38}K. A proposed ℓ=0 resonance in the ^{38}K+p system has been identified at 679(2) keV with an associated strength of 120_{-30}^{+50} meV. Upper limits of 1.16 (3.5) and 8.6 (26) meV at the 68% (95%) confidence level were also established for two further expected ℓ=0 resonances at 386 and 515 keV, respectively. The present results have reduced uncertainties in the ^{38}K(p,γ)^{39}Ca reaction rate at temperatures of 0.4 GK by more than 2 orders of magnitude and indicate that Ar and Ca may be ejected in observable quantities by oxygen-neon novae. However, based on the newly evaluated rate, the ^{38}K(p,γ)^{39}Ca path is unlikely to be responsible for the production of Ar and Ca in significantly enhanced quantities relative to solar abundances.
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Affiliation(s)
- G Lotay
- Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom
- National Physical Laboratory, Teddington, Middlesex TW11 0LW, United Kingdom
| | - G Christian
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - C Ruiz
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - C Akers
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
- Department of Physics, The University of York, York YO10 5DD, United Kingdom
| | - D S Burke
- Department of Physics and Astronomy, McMaster University, Hamilton, Ontario L8S 4M1, Canada
| | - W N Catford
- Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom
| | - A A Chen
- Department of Physics and Astronomy, McMaster University, Hamilton, Ontario L8S 4M1, Canada
| | - D Connolly
- Colorado School of Mines, Golden, Colorado 80401, USA
| | - B Davids
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - J Fallis
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - U Hager
- Colorado School of Mines, Golden, Colorado 80401, USA
| | - D A Hutcheon
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - A Mahl
- Colorado School of Mines, Golden, Colorado 80401, USA
| | - A Rojas
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - X Sun
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
- McGill University, Montreal, Quebec H3A 0G4, Canada
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Jones MD, Kohley Z, Baumann T, Christian G, DeYoung PA, Finck JE, Frank N, Haring-Kaye RA, Kuchera AN, Luther B, Mosby S, Smith JK, Snyder J, Spyrou A, Stephenson SL, Thoennessen M. Search for 4 ncontributions in the reaction 14Be(CH 2,X) 10He. EPJ Web of Conferences 2016. [DOI: 10.1051/epjconf/201611306006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Margerin V, Lotay G, Woods PJ, Aliotta M, Christian G, Davids B, Davinson T, Doherty DT, Fallis J, Howell D, Kirsebom OS, Mountford DJ, Rojas A, Ruiz C, Tostevin JA. Inverse Kinematic Study of the (26g)Al(d,p)(27)Al Reaction and Implications for Destruction of (26)Al in Wolf-Rayet and Asymptotic Giant Branch Stars. Phys Rev Lett 2015; 115:062701. [PMID: 26296114 DOI: 10.1103/physrevlett.115.062701] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Indexed: 06/04/2023]
Abstract
In Wolf-Rayet and asymptotic giant branch (AGB) stars, the (26g)Al(p,γ)(27)Si reaction is expected to govern the destruction of the cosmic γ-ray emitting nucleus (26)Al. The rate of this reaction, however, is highly uncertain due to the unknown properties of key resonances in the temperature regime of hydrogen burning. We present a high-resolution inverse kinematic study of the (26g)Al(d,p)(27)Al reaction as a method for constraining the strengths of key astrophysical resonances in the (26g)Al(p,γ)(27)Si reaction. In particular, the results indicate that the resonance at E(r)=127 keV in (27)Si determines the entire (26g)Al(p,γ)(27)Si reaction rate over almost the complete temperature range of Wolf-Rayet stars and AGB stars.
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Affiliation(s)
- V Margerin
- School of Physics and Astronomy, University of Edinburgh, Edinburgh, EH9 3FD, United Kingdom
| | - G Lotay
- School of Physics and Astronomy, University of Edinburgh, Edinburgh, EH9 3FD, United Kingdom
- Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom
- National Physical Laboratory, Teddington, Middlesex TW11 0LW, United Kingdom
| | - P J Woods
- School of Physics and Astronomy, University of Edinburgh, Edinburgh, EH9 3FD, United Kingdom
| | - M Aliotta
- School of Physics and Astronomy, University of Edinburgh, Edinburgh, EH9 3FD, United Kingdom
| | - G Christian
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - B Davids
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - T Davinson
- School of Physics and Astronomy, University of Edinburgh, Edinburgh, EH9 3FD, United Kingdom
| | - D T Doherty
- School of Physics and Astronomy, University of Edinburgh, Edinburgh, EH9 3FD, United Kingdom
| | - J Fallis
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - D Howell
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - O S Kirsebom
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - D J Mountford
- School of Physics and Astronomy, University of Edinburgh, Edinburgh, EH9 3FD, United Kingdom
| | - A Rojas
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - C Ruiz
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
| | - J A Tostevin
- Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom
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Tomlinson JR, Fallis J, Laird AM, Fox SP, Akers C, Alcorta M, Bentley MA, Christian G, Davids B, Davinson T, Fulton BR, Galinski N, Rojas A, Ruiz C, de Séréville N, Shen M, Shotter AC. Measurement of 23Na(α,p)26Mg at Energies Relevant to 26Al Production in Massive Stars. Phys Rev Lett 2015; 115:052702. [PMID: 26274415 DOI: 10.1103/physrevlett.115.052702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Indexed: 06/04/2023]
Abstract
26Al is an important radioisotope in astrophysics that provides evidence of ongoing nucleosynthesis in the Galaxy. The 23Na(α, p)26Mg reaction has been identified by a sensitivity study as being one of the most important reactions for the production of 26Al in the convective C/Ne burning shell of massive stars. Owing to large uncertainties in previous experimental data, model calculations are used for the reaction rate of 23Na(α, p)26Mg in this sensitivity study. Current experimental data suggest a reaction rate a factor of ∼40 higher than model calculations. However, a new measurement of this reaction cross section has been made in inverse kinematics in the energy range E(c.m.)=1.28-3.15 MeV at TRIUMF, and found to be in reasonable agreement with the model calculation. A new reaction rate is calculated and tight constraints on the uncertainty in the production of 26Al, due to this reaction, are determined.
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Affiliation(s)
- J R Tomlinson
- The University of York, Heslington, York YO10 5DD, United Kingdom
| | - J Fallis
- TRIUMF, 4004 Westbrook Mall, Vancouver, British Columbia V6T 2A3, Canada
| | - A M Laird
- The University of York, Heslington, York YO10 5DD, United Kingdom
| | - S P Fox
- The University of York, Heslington, York YO10 5DD, United Kingdom
| | - C Akers
- The University of York, Heslington, York YO10 5DD, United Kingdom
- TRIUMF, 4004 Westbrook Mall, Vancouver, British Columbia V6T 2A3, Canada
| | - M Alcorta
- TRIUMF, 4004 Westbrook Mall, Vancouver, British Columbia V6T 2A3, Canada
| | - M A Bentley
- The University of York, Heslington, York YO10 5DD, United Kingdom
| | - G Christian
- TRIUMF, 4004 Westbrook Mall, Vancouver, British Columbia V6T 2A3, Canada
| | - B Davids
- TRIUMF, 4004 Westbrook Mall, Vancouver, British Columbia V6T 2A3, Canada
| | - T Davinson
- School of Physics and Astronomy, The University of Edinburgh, James Clerk Maxwell Building, Mayfield Road, Edinburgh EH9 3FD, United Kingdom
| | - B R Fulton
- The University of York, Heslington, York YO10 5DD, United Kingdom
| | - N Galinski
- TRIUMF, 4004 Westbrook Mall, Vancouver, British Columbia V6T 2A3, Canada
| | - A Rojas
- TRIUMF, 4004 Westbrook Mall, Vancouver, British Columbia V6T 2A3, Canada
| | - C Ruiz
- TRIUMF, 4004 Westbrook Mall, Vancouver, British Columbia V6T 2A3, Canada
| | - N de Séréville
- Institut de Physique Nucléaire d'Orsay, IN2P3-CNRS and Univ Paris-Sud, F-91405 Orsay Cedex, France
| | - M Shen
- TRIUMF, 4004 Westbrook Mall, Vancouver, British Columbia V6T 2A3, Canada
| | - A C Shotter
- School of Physics and Astronomy, The University of Edinburgh, James Clerk Maxwell Building, Mayfield Road, Edinburgh EH9 3FD, United Kingdom
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Heuck A, Christian G. Update Hüftgelenk. ROFO-FORTSCHR RONTG 2015. [DOI: 10.1055/s-0035-1551276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Merz C, Strecker A, Sykora J, Hill O, Christian G, Fricke H, Angel P, Peterziel H. Abstract 4986: APG101 inhibits CD95-Ligand induced invasion of glioblastoma in 3D-models in vitro and ex vivo. Cancer Res 2014. [DOI: 10.1158/1538-7445.am2014-4986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
CD95 (APO-1/Fas) is a receptor that belongs to the Tumor Necrosis Factor Receptor Super Family (TNFRSF). Originally discovered as a death receptor inducing apoptosis upon binding to its ligand CD178 (CD95L/FasL), recent research indicates that CD95 also mediates non-apoptotic functions (e.g. liver regeneration, neuronal development, inflammation and cellular migration/invasion of tumor cells) depending on the cellular context. The potential impact on multiple cellular processes classifies the CD95 pathway as an attractive target for pharmacological interference. Apogenix developed APG101, a recombinant human fusion protein consisting of the extracellular domain of CD95 and the Fc-domain of an IgG antibody for the treatment of glioblastoma, a malignancy characterized by aggressive and invasive growth. Preclinical development activities to elucidate the mode of action of APG101 included the comparison of 3-dimensional in vitro and ex vivo models employing U87-MG and U373-MG cells on murine organotypic brain tissue cultures. Expression of CD95L and CD95 in these cells was reduced by semi-stable transfection of shRNA vectors to assess contribution of the CD95/CD95L system to invasion and proliferation of glioma cell lines and the anti-invasive effect of APG101 treatment. While knockdown of CD95 leads to death of U373-MG cells, we observed significant reduction of proliferation rates in U87-MG cells. The effect of CD95L knockdown on proliferation was only minor in U87-MG and was absent in U373-MG cells. Consistently, we found that treatment of glioma cells with APG101 had no effect on proliferation rates or cell cycle regulation of either cell line. The main effect of CD95L knockdown was a strongly reduced invasiveness of both cell lines in vitro and ex vivo. Invasiveness could be restored by exogenous addition of recombinant CD95L, and this induced invasion was inhibited in the presence of APG101. In contrast, a CD95L binding defective CD95-Fc mutant APG122 did not have an anti-invasive effect in our experimental models. We conclude that: Results obtained from the in vitro and ex vivo assay models reflect each other and are suitable to study the role of CD95 signaling in tumor cell invasion activation of CD95 on glioma cells by CD95L contributes to invasive spread of tumor cells to the surrounding brain tissue, and Apogenix drug APG101 is able to block the pro-invasive activity of CD95L. Based on these observations, an important mode of action for APG101 is inhibition of CD95 ligand induced invasion of glioma cells.
Citation Format: Christian Merz, Alexander Strecker, Jaromir Sykora, Oliver Hill, Gieffers Christian, Harald Fricke, Peter Angel, Heike Peterziel. APG101 inhibits CD95-Ligand induced invasion of glioblastoma in 3D-models in vitro and ex vivo. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4986. doi:10.1158/1538-7445.AM2014-4986
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White GR, Ainsworth R, Akagi T, Alabau-Gonzalvo J, Angal-Kalinin D, Araki S, Aryshev A, Bai S, Bambade P, Bett DR, Blair G, Blanch C, Blanco O, Blaskovic-Kraljevic N, Bolzon B, Boogert S, Burrows PN, Christian G, Corner L, Davis MR, Faus-Golfe A, Fukuda M, Gao J, García-Morales H, Geffroy N, Hayano H, Heo AY, Hildreth M, Honda Y, Huang JY, Hwang WH, Iwashita Y, Jang S, Jeremie A, Kamiya Y, Karataev P, Kim ES, Kim HS, Kim SH, Kim YI, Komamiya S, Kubo K, Kume T, Kuroda S, Lam B, Lekomtsev K, Liu S, Lyapin A, Marin E, Masuzawa M, McCormick D, Naito T, Nelson J, Nevay LJ, Okugi T, Omori T, Oroku M, Park H, Park YJ, Perry C, Pfingstner J, Phinney N, Rawankar A, Renier Y, Resta-López J, Ross M, Sanuki T, Schulte D, Seryi A, Shevelev M, Shimizu H, Snuverink J, Spencer C, Suehara T, Sugahara R, Takahashi T, Tanaka R, Tauchi T, Terunuma N, Tomás R, Urakawa J, Wang D, Warden M, Wendt M, Wolski A, Woodley M, Yamaguchi Y, Yamanaka T, Yan J, Yokoya K, Zimmermann F. Experimental validation of a novel compact focusing scheme for future energy-frontier linear lepton colliders. Phys Rev Lett 2014; 112:034802. [PMID: 24484144 DOI: 10.1103/physrevlett.112.034802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Indexed: 06/03/2023]
Abstract
A novel scheme for the focusing of high-energy leptons in future linear colliders was proposed in 2001 [P. Raimondi and A. Seryi, Phys. Rev. Lett. 86, 3779 (2001)]. This scheme has many advantageous properties over previously studied focusing schemes, including being significantly shorter for a given energy and having a significantly better energy bandwidth. Experimental results from the ATF2 accelerator at KEK are presented that validate the operating principle of such a scheme by demonstrating the demagnification of a 1.3 GeV electron beam down to below 65 nm in height using an energy-scaled version of the compact focusing optics designed for the ILC collider.
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Affiliation(s)
- G R White
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025-7090, USA
| | - R Ainsworth
- John Adams Institute for Accelerator Science at Royal Holloway University of London, Egham Hill, Egham, Surrey TW20 0EX, United Kingdom
| | - T Akagi
- Department of Physics, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8526, Japan
| | - J Alabau-Gonzalvo
- European Organization for Nuclear Research (CERN), CH-1211 Geneva 23, Switzerland
| | - D Angal-Kalinin
- CLRC: Daresbury Laboratory, Daresbury, Warrington, Cheshire WA4 4AD, United Kingdom
| | - S Araki
- High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - A Aryshev
- High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - S Bai
- Institute of High Energy Physics (IHEP), Chinese Academy of Sciences (CAS), Beijing, China
| | - P Bambade
- LAL, Universite Paris-Sud, CNRS/IN2P3, Orsay, France
| | - D R Bett
- John Adams Institute for Accelerator Science at University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH, United Kingdom
| | - G Blair
- John Adams Institute for Accelerator Science at Royal Holloway University of London, Egham Hill, Egham, Surrey TW20 0EX, United Kingdom and Science and Technology Facilities Council, Polaris House, North Star Avenue, Swindon SN2 1SZ, United Kingdom
| | - C Blanch
- Universidad de Valencia - Instituto de Física Corpuscular (IFC), Edificio Institutos de Investigación, c/ Catedrático José Beltrán, 2, E-46980 Paterna, Spain
| | - O Blanco
- European Organization for Nuclear Research (CERN), CH-1211 Geneva 23, Switzerland and LAL, Universite Paris-Sud, CNRS/IN2P3, Orsay, France
| | - N Blaskovic-Kraljevic
- John Adams Institute for Accelerator Science at University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH, United Kingdom
| | - B Bolzon
- European Organization for Nuclear Research (CERN), CH-1211 Geneva 23, Switzerland and CLRC: Daresbury Laboratory, Daresbury, Warrington, Cheshire WA4 4AD, United Kingdom and Department of Physics, Oliver Lodge Laboratory, University of Liverpool, Oxford St., Liverpool L69 3BX, United Kingdom
| | - S Boogert
- John Adams Institute for Accelerator Science at Royal Holloway University of London, Egham Hill, Egham, Surrey TW20 0EX, United Kingdom
| | - P N Burrows
- John Adams Institute for Accelerator Science at University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH, United Kingdom
| | - G Christian
- John Adams Institute for Accelerator Science at University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH, United Kingdom
| | - L Corner
- John Adams Institute for Accelerator Science at University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH, United Kingdom
| | - M R Davis
- John Adams Institute for Accelerator Science at University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH, United Kingdom
| | - A Faus-Golfe
- Universidad de Valencia - Instituto de Física Corpuscular (IFC), Edificio Institutos de Investigación, c/ Catedrático José Beltrán, 2, E-46980 Paterna, Spain
| | - M Fukuda
- High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - J Gao
- Institute of High Energy Physics (IHEP), Chinese Academy of Sciences (CAS), Beijing, China
| | - H García-Morales
- European Organization for Nuclear Research (CERN), CH-1211 Geneva 23, Switzerland and Universitat Politécnica de Catalunya, BarcelonaTech, C. Jordi Girona, 31. 08034 Barcelona, Spain
| | - N Geffroy
- LAPP-Universite de Savoie-CNRS/IN2P3, Annecy-le-Vieux, France
| | - H Hayano
- High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - A Y Heo
- Department of Physics, Kyungpook National University, 1370 San Kyuk-dong, Puk ku, Taegu 635, South Korea
| | - M Hildreth
- University of Notre Dame, Notre Dame, Indiana 46556, USA
| | - Y Honda
- High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - J Y Huang
- Pohang Accelerator Laboratory, POSTECH (Pohang University of Science and Technology), San-31 Hyoja-dong, Pohang 790-784, South Korea
| | - W H Hwang
- Pohang Accelerator Laboratory, POSTECH (Pohang University of Science and Technology), San-31 Hyoja-dong, Pohang 790-784, South Korea
| | - Y Iwashita
- Institute for Chemical Research (ICR), Nuclear Science Research Facility, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
| | - S Jang
- Department of Physics, Kyungpook National University, 1370 San Kyuk-dong, Puk ku, Taegu 635, South Korea
| | - A Jeremie
- LAPP-Universite de Savoie-CNRS/IN2P3, Annecy-le-Vieux, France
| | - Y Kamiya
- Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113, Japan
| | - P Karataev
- John Adams Institute for Accelerator Science at Royal Holloway University of London, Egham Hill, Egham, Surrey TW20 0EX, United Kingdom
| | - E S Kim
- Department of Physics, Kyungpook National University, 1370 San Kyuk-dong, Puk ku, Taegu 635, South Korea
| | - H S Kim
- Department of Physics, Kyungpook National University, 1370 San Kyuk-dong, Puk ku, Taegu 635, South Korea
| | - S H Kim
- Pohang Accelerator Laboratory, POSTECH (Pohang University of Science and Technology), San-31 Hyoja-dong, Pohang 790-784, South Korea
| | - Y I Kim
- John Adams Institute for Accelerator Science at University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH, United Kingdom
| | - S Komamiya
- Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113, Japan
| | - K Kubo
- High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - T Kume
- High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - S Kuroda
- High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - B Lam
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025-7090, USA
| | - K Lekomtsev
- High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - S Liu
- LAL, Universite Paris-Sud, CNRS/IN2P3, Orsay, France
| | - A Lyapin
- John Adams Institute for Accelerator Science at Royal Holloway University of London, Egham Hill, Egham, Surrey TW20 0EX, United Kingdom
| | - E Marin
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025-7090, USA
| | - M Masuzawa
- High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - D McCormick
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025-7090, USA
| | - T Naito
- High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - J Nelson
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025-7090, USA
| | - L J Nevay
- John Adams Institute for Accelerator Science at University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH, United Kingdom and John Adams Institute for Accelerator Science at Royal Holloway University of London, Egham Hill, Egham, Surrey TW20 0EX, United Kingdom
| | - T Okugi
- High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - T Omori
- High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - M Oroku
- Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113, Japan
| | - H Park
- Department of Physics, Kyungpook National University, 1370 San Kyuk-dong, Puk ku, Taegu 635, South Korea
| | - Y J Park
- Pohang Accelerator Laboratory, POSTECH (Pohang University of Science and Technology), San-31 Hyoja-dong, Pohang 790-784, South Korea
| | - C Perry
- John Adams Institute for Accelerator Science at University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH, United Kingdom
| | - J Pfingstner
- European Organization for Nuclear Research (CERN), CH-1211 Geneva 23, Switzerland
| | - N Phinney
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025-7090, USA
| | - A Rawankar
- High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - Y Renier
- European Organization for Nuclear Research (CERN), CH-1211 Geneva 23, Switzerland
| | - J Resta-López
- Universidad de Valencia - Instituto de Física Corpuscular (IFC), Edificio Institutos de Investigación, c/ Catedrático José Beltrán, 2, E-46980 Paterna, Spain
| | - M Ross
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025-7090, USA
| | - T Sanuki
- Tohoku University, 28 Kawauchi, Aoba-ku, Sendai, 980-8576 Japan
| | - D Schulte
- European Organization for Nuclear Research (CERN), CH-1211 Geneva 23, Switzerland
| | - A Seryi
- John Adams Institute for Accelerator Science at University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH, United Kingdom
| | - M Shevelev
- High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - H Shimizu
- High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - J Snuverink
- John Adams Institute for Accelerator Science at Royal Holloway University of London, Egham Hill, Egham, Surrey TW20 0EX, United Kingdom
| | - C Spencer
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025-7090, USA
| | - T Suehara
- Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113, Japan
| | - R Sugahara
- High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - T Takahashi
- Department of Physics, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8526, Japan
| | - R Tanaka
- Department of Physics, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8526, Japan
| | - T Tauchi
- High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - N Terunuma
- High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - R Tomás
- European Organization for Nuclear Research (CERN), CH-1211 Geneva 23, Switzerland
| | - J Urakawa
- High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - D Wang
- Institute of High Energy Physics (IHEP), Chinese Academy of Sciences (CAS), Beijing, China
| | - M Warden
- John Adams Institute for Accelerator Science at University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH, United Kingdom
| | - M Wendt
- European Organization for Nuclear Research (CERN), CH-1211 Geneva 23, Switzerland
| | - A Wolski
- Department of Physics, Oliver Lodge Laboratory, University of Liverpool, Oxford St., Liverpool L69 3BX, United Kingdom
| | - M Woodley
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025-7090, USA
| | - Y Yamaguchi
- Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113, Japan
| | - T Yamanaka
- Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113, Japan
| | - J Yan
- Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113, Japan
| | - K Yokoya
- High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - F Zimmermann
- European Organization for Nuclear Research (CERN), CH-1211 Geneva 23, Switzerland
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12
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Akers C, Laird AM, Fulton BR, Ruiz C, Bardayan DW, Buchmann L, Christian G, Davids B, Erikson L, Fallis J, Hager U, Hutcheon D, Martin L, Murphy ASJ, Nelson K, Spyrou A, Stanford C, Ottewell D, Rojas A. Measurement of radiative proton capture on 18F and implications for oxygen-neon novae. Phys Rev Lett 2013; 110:262502. [PMID: 23848867 DOI: 10.1103/physrevlett.110.262502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2013] [Indexed: 06/02/2023]
Abstract
The rate of the 18F(p,γ)19Ne reaction affects the final abundance of the γ-ray observable radioisotope 18F, produced in novae. However, no successful measurement of this reaction exists and the rate used is calculated from incomplete information on the contributing resonances. Of the two resonances thought to play a significant role, one has a radiative width estimated from the assumed analogue state in the mirror nucleus, 19F. The second does not have an analogue state assignment at all, resulting in an arbitrary radiative width being assumed. Here, we report the first successful direct measurement of the 18F(p,γ)^19Ne reaction. The strength of the 665 keV resonance (Ex=7.076 MeV) is found to be over an order of magnitude weaker than currently assumed in nova models. Reaction rate calculations show that this resonance therefore plays no significant role in the destruction of ^{18}F at any astrophysical energy.
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Affiliation(s)
- C Akers
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
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13
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Kohley Z, Baumann T, Bazin D, Christian G, DeYoung PA, Finck JE, Frank N, Jones M, Lunderberg E, Luther B, Mosby S, Nagi T, Smith JK, Snyder J, Spyrou A, Thoennessen M. Study of two-neutron radioactivity in the decay of 26O. Phys Rev Lett 2013; 110:152501. [PMID: 25167255 DOI: 10.1103/physrevlett.110.152501] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Indexed: 06/03/2023]
Abstract
A new technique was developed to measure the lifetimes of neutron unbound nuclei in the picosecond range. The decay of 26O→24O+n+n was examined as it had been predicted to have an appreciable lifetime due to the unique structure of the neutron-rich oxygen isotopes. The half-life of 26O was extracted as 4.5(-1.5)(+1.1)(stat)±3(syst) ps. This corresponds to 26O having a finite lifetime at an 82% confidence level and, thus, suggests the possibility of two-neutron radioactivity.
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Affiliation(s)
- Z Kohley
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA and Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, USA
| | - T Baumann
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
| | - D Bazin
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
| | - G Christian
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - P A DeYoung
- Department of Physics, Hope College, Holland, Michigan 49423, USA
| | - J E Finck
- Department of Physics, Central Michigan University, Mount Pleasant, Michigan 48859, USA
| | - N Frank
- Department of Physics and Astronomy, Augustana College, Rock Island, Illinois 61201, USA
| | - M Jones
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - E Lunderberg
- Department of Physics, Hope College, Holland, Michigan 49423, USA
| | - B Luther
- Department of Physics, Concordia College, Moorhead, Minnesota 56562, USA
| | - S Mosby
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - T Nagi
- Department of Physics, Hope College, Holland, Michigan 49423, USA
| | - J K Smith
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - J Snyder
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - A Spyrou
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - M Thoennessen
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
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14
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Kohley Z, Snyder J, Baumann T, Christian G, DeYoung PA, Finck JE, Haring-Kaye RA, Jones M, Lunderberg E, Luther B, Mosby S, Simon A, Smith JK, Spyrou A, Stephenson SL, Thoennessen M. Unresolved question of the 10He ground state resonance. Phys Rev Lett 2012; 109:232501. [PMID: 23368186 DOI: 10.1103/physrevlett.109.232501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2012] [Indexed: 06/01/2023]
Abstract
The ground state of (10)He was populated using a 2p2n-removal reaction from a 59 MeV/u (14)Be beam. The decay energy of the three-body system, (8)He+n+n, was measured and a resonance was observed at E=1.60(25) MeV with a 1.8(4) MeV width. This result is in agreement with previous invariant mass spectroscopy measurements, using the (11)Li(-p) reaction, but is inconsistent with recent transfer reaction results. The proposed explanation that the difference, about 500 keV, is due to the effect of the extended halo nature of (11)Li in the one-proton knockout reaction is no longer valid as the present work demonstrates that the discrepancy between the transfer reaction results persists despite using a very different reaction mechanism, (14)Be(-2p2n).
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Affiliation(s)
- Z Kohley
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA.
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15
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Lunderberg E, DeYoung PA, Kohley Z, Attanayake H, Baumann T, Bazin D, Christian G, Divaratne D, Grimes SM, Haagsma A, Finck JE, Frank N, Luther B, Mosby S, Nagi T, Peaslee GF, Schiller A, Snyder J, Spyrou A, Strongman MJ, Thoennessen M. Evidence for the ground-state resonance of 26O. Phys Rev Lett 2012; 108:142503. [PMID: 22540789 DOI: 10.1103/physrevlett.108.142503] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2011] [Indexed: 05/31/2023]
Abstract
Evidence for the ground state of the neutron-unbound nucleus (26)O was observed for the first time in the single proton-knockout reaction from a 82 MeV/u (27)F beam. Neutrons were measured in coincidence with (24)O fragments. (26)O was determined to be unbound by 150(-150)(+50) keV from the observation of low-energy neutrons. This result agrees with recent shell-model calculations based on microscopic two- and three-nucleon forces.
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Affiliation(s)
- E Lunderberg
- Department of Physics, Hope College, Holland, Michigan 49423, USA
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16
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Spyrou A, Kohley Z, Baumann T, Bazin D, Brown BA, Christian G, DeYoung PA, Finck JE, Frank N, Lunderberg E, Mosby S, Peters WA, Schiller A, Smith JK, Snyder J, Strongman MJ, Thoennessen M, Volya A. First observation of ground state dineutron decay: 16Be. Phys Rev Lett 2012; 108:102501. [PMID: 22463404 DOI: 10.1103/physrevlett.108.102501] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2011] [Indexed: 05/31/2023]
Abstract
We report on the first observation of dineutron emission in the decay of 16Be. A single-proton knockout reaction from a 53 MeV/u 17B beam was used to populate the ground state of 16Be. 16Be is bound with respect to the emission of one neutron and unbound to two-neutron emission. The dineutron character of the decay is evidenced by a small emission angle between the two neutrons. The two-neutron separation energy of 16Be was measured to be 1.35(10) MeV, in good agreement with shell model calculations, using standard interactions for this mass region.
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Affiliation(s)
- A Spyrou
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA.
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17
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Christian G, Frank N, Ash S, Baumann T, Bazin D, Brown J, DeYoung PA, Finck JE, Gade A, Grinyer GF, Grovom A, Hinnefeld JD, Lunderberg EM, Luther B, Mosby M, Mosby S, Nagi T, Peaslee GF, Rogers WF, Smith JK, Snyder J, Spyrou A, Strongman MJ, Thoennessen M, Warren M, Weisshaar D, Wersal A. Exploring the low-Z shore of the island of inversion at n=19. Phys Rev Lett 2012; 108:032501. [PMID: 22400733 DOI: 10.1103/physrevlett.108.032501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Indexed: 05/31/2023]
Abstract
The technique of invariant mass spectroscopy has been used to measure, for the first time, the ground state energy of neutron-unbound (28)F, determined to be a resonance in the (27)F+n continuum at 220(50) keV. States in (28)F were populated by the reactions of a 62 MeV/u (29)Ne beam impinging on a 288 mg/cm(2) beryllium target. The measured (28)F ground state energy is in good agreement with USDA/USDB shell model predictions, indicating that pf shell intruder configurations play only a small role in the ground state structure of (28)F and establishing a low-Z boundary of the island of inversion for N=19 isotones.
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Affiliation(s)
- G Christian
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA.
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18
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Hoffman CR, Baumann T, Bazin D, Brown J, Christian G, DeYoung PA, Finck JE, Frank N, Hinnefeld J, Howes R, Mears P, Mosby E, Mosby S, Reith J, Rizzo B, Rogers WF, Peaslee G, Peters WA, Schiller A, Scott MJ, Tabor SL, Thoennessen M, Voss PJ, Williams T. Determination of the N=16 shell closure at the oxygen drip line. Phys Rev Lett 2008; 100:152502. [PMID: 18518100 DOI: 10.1103/physrevlett.100.152502] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2007] [Indexed: 05/26/2023]
Abstract
The neutron unbound ground state of (25)O (Z=8, N=17) was observed for the first time in a proton knockout reaction from a (26)F beam. A single resonance was found in the invariant mass spectrum corresponding to a neutron decay energy of 770_+20(-10) keV with a total width of 172(30) keV. The N=16 shell gap was established to be 4.86(13) MeV by the energy difference between the nu1s(1/2) and nu0d(3/2) orbitals. The neutron separation energies for (25)O agree with the calculations of the universal sd shell model interaction. This interaction incorrectly predicts an (26)O ground state that is bound to two-neutron decay by 1 MeV, leading to a discrepancy between the theoretical calculations and experiment as to the particle stability of (26)O. The observed decay width was found to be on the order of a factor of 2 larger than the calculated single-particle width using a Woods-Saxon potential.
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Affiliation(s)
- C R Hoffman
- Department of Physics, Florida State University, Tallahassee, FL 32303, USA.
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Chiriac L, Christian G, Bolohan R, Tintoiu I. P.1.22 Cavotricuspid isthmus anatomy in flutter ablation of right aneurismal atrium using non contact mapping. Europace 2003. [DOI: 10.1016/eupace/4.supplement_1.a38-b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Affiliation(s)
- L. Chiriac
- Army's Clinic Emergency Center of Cardiovascular Disease, Bucharest, Romania
| | - G. Christian
- Army's Clinic Emergency Center of Cardiovascular Disease, Bucharest, Romania
| | - R. Bolohan
- Army's Clinic Emergency Center of Cardiovascular Disease, Bucharest, Romania
| | - I. Tintoiu
- Army's Clinic Emergency Center of Cardiovascular Disease, Bucharest, Romania
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Echo JA, Lamonte N, Christian G, Znamensky V, Ackerman TF, Bodnar RJ. Excitatory amino acid receptor subtype agonists induce feeding in the nucleus accumbens shell in rats: opioid antagonist actions and interactions with mu-opioid agonists. Brain Res 2001; 921:86-97. [PMID: 11720714 DOI: 10.1016/s0006-8993(01)03094-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Administration of mu-opioid receptor subtype agonists into the nucleus accumbens shell elicits feeding which is dependent upon the normal function of mu-, delta- and kappa-opioid receptors, D(1) dopamine receptors and GABA(B) receptors in the nucleus accumbens shell for its full expression. Whereas the AMPA antagonist, DNQX administered into the nucleus accumbens shell elicits a transient, though intense feeding response, feeding is elicited by excitatory amino acid agonists administered into the lateral hypothalamus. The present study examined whether excitatory amino acid agonists elicited feeding following administration into the nucleus accumbens shell of rats, whether such feeding responses were altered by opioid antagonist pretreatment, and whether such feeding responses interacted with feeding elicited by mu-opioid agonists. Both AMPA (0.25-0.5 microg) and NMDA (1 microg) in the nucleus accumbens shell significantly and dose-dependently increased food intake over 4 h. Both feeding responses were blocked by naltrexone pretreatment in the nucleus accumbens shell. The mu-opioid agonist, [D-Ala(2),NMe-Phe(4),Gly-ol(5)]-enkephalin in the nucleus accumbens shell significantly increased food intake which was significantly enhanced by AMPA cotreatment. This enhanced feeding response was in turn blocked by pretreatment with either general or mu-selective opioid antagonists. In contrast, cotreatment of NMDA and the mu-opioid agonist in the nucleus accumbens shell elicited feeding which was significantly less than that elicited by either treatment alone. These data indicate the presence of important interactions between excitatory amino acid receptors and mu-opioid receptors in the nucleus accumbens shell in mediating feeding responses in nondeprived, ad libitum-fed rats.
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MESH Headings
- Analgesics, Opioid/pharmacology
- Animals
- Dose-Response Relationship, Drug
- Drug Interactions/physiology
- Enkephalin, Ala(2)-MePhe(4)-Gly(5)-/pharmacology
- Excitatory Amino Acid Agonists/pharmacology
- Feeding Behavior/drug effects
- Feeding Behavior/physiology
- Male
- N-Methylaspartate/pharmacology
- Naltrexone/pharmacology
- Narcotic Antagonists/pharmacology
- Neurons/drug effects
- Neurons/metabolism
- Nucleus Accumbens/drug effects
- Nucleus Accumbens/metabolism
- Rats
- Rats, Sprague-Dawley
- Receptors, AMPA/agonists
- Receptors, AMPA/metabolism
- Receptors, N-Methyl-D-Aspartate/agonists
- Receptors, N-Methyl-D-Aspartate/metabolism
- Receptors, Opioid, mu/agonists
- Receptors, Opioid, mu/antagonists & inhibitors
- Receptors, Opioid, mu/metabolism
- Synaptic Transmission/drug effects
- Synaptic Transmission/physiology
- alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid/pharmacology
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Affiliation(s)
- J A Echo
- Department of Psychology and Neuropsychology Doctoral Sub-Program, Queens College, City University of New York, 65-30 Kissena Boulevard, Flushing, NY 11367, USA
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Znamensky V, Echo JA, Lamonte N, Christian G, Ragnauth A, Bodnar RJ. gamma-Aminobutyric acid receptor subtype antagonists differentially alter opioid-induced feeding in the shell region of the nucleus accumbens in rats. Brain Res 2001; 906:84-91. [PMID: 11430864 DOI: 10.1016/s0006-8993(01)02558-6] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Food intake is significantly increased by administration of mu-selective opioid agonists into the nucleus accumbens, particularly its shell region. Pretreatment with either opioid (mu, delta(1), delta(2) or kappa(1)) or dopaminergic (D(1)) receptor antagonists in the nucleus accumbens shell reduce mu opioid agonist-induced feeding. Selective GABA(A) (muscimol) and GABA(B) (baclofen) agonists administered into the nucleus accumbens shell each stimulate feeding which is respectively and selectively blocked by GABA(A) (bicuculline) and GABA(B) (saclofen) antagonists. The present study investigated whether feeding elicited by the mu-selective opioid agonist, [D-Ala(2),NMe(4),Gly-ol(5)]-enkephalin in the nucleus accumbens shell was decreased by intra-accumbens pretreatment with an equimolar dose range of either GABA(A) or GABA(B) antagonists, and further, whether general opioid or selective GABA antagonists decreased feeding elicited by GABA(A) or GABA(B) agonists in the nucleus accumbens shell. Feeding elicited by the mu-selective opioid agonist was dose-dependently increased following intra-accumbens pretreatment with GABA(A) (bicuculline) antagonism; this enhancement was significantly blocked by pretreatment with general or mu-selective opioid antagonists. In contrast, mu opioid agonist-induced feeding elicited from the nucleus accumbens shell was dose-dependently decreased by GABA(B) (saclofen) antagonism. Neither bicuculline nor saclofen in the nucleus accumbens shell altered baseline food intake. Whereas muscimol-induced feeding elicited from the nucleus accumbens shell was reduced by bicuculline and naltrexone, but not saclofen pretreatment, baclofen-induced feeding elicited from the nucleus accumbens shell was reduced by saclofen, but not by bicuculline or naltrexone. These data indicate that GABA(A) and GABA(B) receptor subtype antagonists differentially affect feeding elicited by mu opioid receptor agonists within the nucleus accumbens shell in rats.
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Affiliation(s)
- V Znamensky
- Department of Psychology and Neuropsychology Doctoral Sub-Program, Queens College, City University of New York, 65--30 Kissena Boulevard, Flushing, NY 11367, USA
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