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Campbell SE, Bollen G, Brown BA, Dockery A, Ireland CM, Minamisono K, Puentes D, Rickey BJ, Ringle R, Yandow IT, Fossez K, Ortiz-Cortes A, Schwarz S, Sumithrarachchi CS, Villari ACC. Precision Mass Measurement of the Proton Dripline Halo Candidate ^{22}Al. Phys Rev Lett 2024; 132:152501. [PMID: 38683002 DOI: 10.1103/physrevlett.132.152501] [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: 12/27/2023] [Accepted: 03/12/2024] [Indexed: 05/01/2024]
Abstract
We report the first mass measurement of the proton-halo candidate ^{22}Al performed with the low energy beam ion trap facility's 9.4 T Penning trap mass spectrometer at facility for rare isotope beams. This measurement completes the mass information for the lightest remaining proton-dripline nucleus achievable with Penning traps. ^{22}Al has been the subject of recent interest regarding a possible halo structure from the observation of an exceptionally large isospin asymmetry [J. Lee et al., Large isospin asymmetry in Si22/O22 Mirror Gamow-Teller transitions reveals the halo structure of ^{22}Al, Phys. Rev. Lett. 125, 192503 (2020).PRLTAO0031-900710.1103/PhysRevLett.125.192503]. The measured mass excess value of ME=18 092.5(3) keV, corresponding to an exceptionally small proton separation energy of S_{p}=100.4(8) keV, is compatible with the suggested halo structure. Our result agrees well with predictions from sd-shell USD Hamiltonians. While USD Hamiltonians predict deformation in the ^{22}Al ground state with minimal 1s_{1/2} occupation in the proton shell, a particle-plus-rotor model in the continuum suggests that a proton halo could form at large quadrupole deformation. These results emphasize the need for a charge radius measurement to conclusively determine the halo nature.
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Affiliation(s)
- S E Campbell
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA and Facility for Rare Isotope Beams, East Lansing, Michigan 48824, USA
| | - G Bollen
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA and Facility for Rare Isotope Beams, East Lansing, Michigan 48824, USA
| | - B A Brown
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA and Facility for Rare Isotope Beams, East Lansing, Michigan 48824, USA
| | - A Dockery
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA and Facility for Rare Isotope Beams, East Lansing, Michigan 48824, USA
| | - C M Ireland
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA and Facility for Rare Isotope Beams, East Lansing, Michigan 48824, USA
| | - K Minamisono
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA and Facility for Rare Isotope Beams, East Lansing, Michigan 48824, USA
| | - D Puentes
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA and Facility for Rare Isotope Beams, East Lansing, Michigan 48824, USA
| | - B J Rickey
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA and Facility for Rare Isotope Beams, East Lansing, Michigan 48824, USA
| | - R Ringle
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA and Facility for Rare Isotope Beams, East Lansing, Michigan 48824, USA
| | - I T Yandow
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA and Facility for Rare Isotope Beams, East Lansing, Michigan 48824, USA
| | - K Fossez
- Department of Physics, Florida State University, Tallahassee, Florida 32306, USA and Physics Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - A Ortiz-Cortes
- Facility for Rare Isotope Beams, East Lansing, Michigan 48824, USA
| | - S Schwarz
- Facility for Rare Isotope Beams, East Lansing, Michigan 48824, USA
| | | | - A C C Villari
- Facility for Rare Isotope Beams, East Lansing, Michigan 48824, USA
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Henriques A, Nash S, Barofsky D, Bollen G, Lapierre A, Schwarz S, Sumithrarachchi C, Zhao Q, Villari ACC. Quantification and purification of isotopic contamination at the ReAccelerator of the Facility for Rare Isotope Beams. Rev Sci Instrum 2023; 94:103306. [PMID: 37815423 DOI: 10.1063/5.0165850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Accepted: 09/19/2023] [Indexed: 10/11/2023]
Abstract
At the ReAccelerator within the Facility for Rare Isotope Beams, a combination of an interchangeable aluminum foil and a silicon detector was developed to quantify isobaric contamination in rare isotope beams. The device is simple to operate and is now used routinely. In this article, we describe the system and show an application of the device to determine the level of contamination of an Si-32 rare isotope beam by stable S-32. In addition, we describe how the new diagnostic device helped confirm an enhancement of the beam purity prior to beam delivery to experiments.
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Affiliation(s)
- A Henriques
- Facility for Rare Isotope Beams, Michigan State University, East Lansing, Michigan 48824, USA
| | - S Nash
- Facility for Rare Isotope Beams, Michigan State University, East Lansing, Michigan 48824, USA
| | - D Barofsky
- Facility for Rare Isotope Beams, Michigan State University, East Lansing, Michigan 48824, USA
| | - G Bollen
- Facility for Rare Isotope Beams, Michigan State University, East Lansing, Michigan 48824, USA
| | - A Lapierre
- Facility for Rare Isotope Beams, Michigan State University, East Lansing, Michigan 48824, USA
| | - S Schwarz
- Facility for Rare Isotope Beams, Michigan State University, East Lansing, Michigan 48824, USA
| | - C Sumithrarachchi
- Facility for Rare Isotope Beams, Michigan State University, East Lansing, Michigan 48824, USA
| | - Q Zhao
- Facility for Rare Isotope Beams, Michigan State University, East Lansing, Michigan 48824, USA
| | - A C C Villari
- Facility for Rare Isotope Beams, Michigan State University, East Lansing, Michigan 48824, USA
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Valverde AA, Brodeur M, Bollen G, Eibach M, Gulyuz K, Hamaker A, Izzo C, Ong WJ, Puentes D, Redshaw M, Ringle R, Sandler R, Schwarz S, Sumithrarachchi CS, Surbrook J, Villari ACC, Yandow IT. Erratum: High-Precision Mass Measurement of ^{56}Cu and the Redirection of the rp-Process Flow [Phys. Rev. Lett. 120, 032701 (2018)]. Phys Rev Lett 2019; 123:239905. [PMID: 31868474 DOI: 10.1103/physrevlett.123.239905] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Indexed: 06/10/2023]
Abstract
This corrects the article DOI: 10.1103/PhysRevLett.120.032701.
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Valverde AA, Brodeur M, Bollen G, Eibach M, Gulyuz K, Hamaker A, Izzo C, Ong WJ, Puentes D, Redshaw M, Ringle R, Sandler R, Schwarz S, Sumithrarachchi CS, Surbrook J, Villari ACC, Yandow IT. High-Precision Mass Measurement of ^{56}Cu and the Redirection of the rp-Process Flow. Phys Rev Lett 2018; 120:032701. [PMID: 29400535 DOI: 10.1103/physrevlett.120.032701] [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: 07/22/2017] [Revised: 10/02/2017] [Indexed: 06/07/2023]
Abstract
We report the mass measurement of ^{56}Cu, using the LEBIT 9.4 T Penning trap mass spectrometer at the National Superconducting Cyclotron Laboratory at Michigan State University. The mass of ^{56}Cu is critical for constraining the reaction rates of the ^{55}Ni(p,γ) ^{56}Cu(p,γ) ^{57}Zn(β^{+}) ^{57}Cu bypass around the ^{56}Ni waiting point. Previous recommended mass excess values have disagreed by several hundred keV. Our new value, ME=-38626.7(7.1) keV, is a factor of 30 more precise than the extrapolated value suggested in the 2012 atomic mass evaluation [Chin. Phys. C 36, 1603 (2012)CPCHCQ1674-113710.1088/1674-1137/36/12/003], and more than a factor of 12 more precise than values calculated using local mass extrapolations, while agreeing with the newest 2016 atomic mass evaluation value [Chin. Phys. C 41, 030003 (2017)CPCHCQ1674-113710.1088/1674-1137/41/3/030003]. The new experimental average, using our new mass and the value from AME2016, is used to calculate the astrophysical ^{55}Ni(p,γ) and ^{56}Cu(p,γ) forward and reverse rates and perform reaction network calculations of the rp process. These show that the rp-process flow redirects around the ^{56}Ni waiting point through the ^{55}Ni(p,γ) route, allowing it to proceed to higher masses more quickly and resulting in a reduction in ashes around this waiting point and an enhancement to higher-mass ashes.
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Affiliation(s)
- A A Valverde
- Department of Physics, University of Notre Dame, Notre Dame, Indiana 46556, USA
| | - M Brodeur
- Department of Physics, University of Notre Dame, Notre Dame, Indiana 46556, USA
| | - G Bollen
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
- Facility for Rare Isotope Beams, East Lansing, Michigan 48824, USA
| | - M Eibach
- Institut für Physik, Universität Greifswald, 17487 Greifswald, Germany
- National Superconducting Cyclotron Laboratory, East Lansing, Michigan 48824, USA
| | - K Gulyuz
- National Superconducting Cyclotron Laboratory, East Lansing, Michigan 48824, USA
| | - A Hamaker
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
- National Superconducting Cyclotron Laboratory, East Lansing, Michigan 48824, USA
| | - C Izzo
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
- National Superconducting Cyclotron Laboratory, East Lansing, Michigan 48824, USA
| | - W-J Ong
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
- National Superconducting Cyclotron Laboratory, East Lansing, Michigan 48824, USA
| | - D Puentes
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
- National Superconducting Cyclotron Laboratory, East Lansing, Michigan 48824, USA
| | - M Redshaw
- National Superconducting Cyclotron Laboratory, East Lansing, Michigan 48824, USA
- Department of Physics, Central Michigan University, Mount Pleasant, Michigan 48859, USA
- Science of Advanced Materials Program, Central Michigan University, Mount Pleasant, Michigan 48859, USA
| | - R Ringle
- National Superconducting Cyclotron Laboratory, East Lansing, Michigan 48824, USA
| | - R Sandler
- Department of Physics, Central Michigan University, Mount Pleasant, Michigan 48859, USA
- Science of Advanced Materials Program, Central Michigan University, Mount Pleasant, Michigan 48859, USA
| | - S Schwarz
- National Superconducting Cyclotron Laboratory, East Lansing, Michigan 48824, USA
| | - C S Sumithrarachchi
- National Superconducting Cyclotron Laboratory, East Lansing, Michigan 48824, USA
| | - J Surbrook
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
- National Superconducting Cyclotron Laboratory, East Lansing, Michigan 48824, USA
| | - A C C Villari
- Facility for Rare Isotope Beams, East Lansing, Michigan 48824, USA
| | - I T Yandow
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
- National Superconducting Cyclotron Laboratory, East Lansing, Michigan 48824, USA
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Silwal R, Lapierre A, Gillaspy JD, Dreiling JM, Blundell SA, Dipti, Borovik A, Gwinner G, Villari ACC, Ralchenko Y, Takacs E. Measuring the difference in nuclear charge radius of Xe isotopes by EUV spectroscopy of highly charged Na-like ions. Phys Rev A (Coll Park) 2018; 98:10.1103/PhysRevA.98.052502. [PMID: 32201753 PMCID: PMC7083102 DOI: 10.1103/physreva.98.052502] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The difference in the mean-square nuclear charge radius of xenon isotopes was measured utilizing a method based on extreme ultraviolet spectroscopy of highly charged Na-like ions. The isotope shift of the Na-like D1 (3s 2 S 1/2 - 3p 2 P 1/2) transition between the 124Xe and 136Xe isotopes was experimentally determined using the electron-beam ion-trap facility at the National Institute of Standards and Technology. The mass-shift and the field-shift coefficients were calculated with enhanced precision by the relativistic many-body perturbation theory and multiconfiguration Dirac-Hartree-Fock method. The mean-square nuclear charge radius difference was found to be δ〈r 2〉136,124 = 0.269(42) fm2. Our result has smaller uncertainty than previous experimental results and agrees with the literature values.
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Affiliation(s)
- R. Silwal
- Department of Physics and Astronomy, Clemson University, Clemson, South Carolina 29634, USA
- National Institute of Standards and Technology (NIST), Gaithersburg, Maryland 20899, USA
| | - A. Lapierre
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
| | - J. D. Gillaspy
- National Institute of Standards and Technology (NIST), Gaithersburg, Maryland 20899, USA
- National Science Foundation, Arlington, Virginia 22314, USA
| | - J. M. Dreiling
- National Institute of Standards and Technology (NIST), Gaithersburg, Maryland 20899, USA
| | - S. A. Blundell
- University of Grenoble Alpes, CEA, CNRS, INAC-SyMMES, 38000 Grenoble, France
| | - Dipti
- National Institute of Standards and Technology (NIST), Gaithersburg, Maryland 20899, USA
| | - A. Borovik
- National Institute of Standards and Technology (NIST), Gaithersburg, Maryland 20899, USA
| | - G. Gwinner
- Department of Physics and Astronomy, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - A. C. C. Villari
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
| | - Yu. Ralchenko
- National Institute of Standards and Technology (NIST), Gaithersburg, Maryland 20899, USA
| | - E. Takacs
- Department of Physics and Astronomy, Clemson University, Clemson, South Carolina 29634, USA
- National Institute of Standards and Technology (NIST), Gaithersburg, Maryland 20899, USA
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Gulyuz K, Bollen G, Brodeur M, Bryce RA, Cooper K, Eibach M, Izzo C, Kwan E, Manukyan K, Morrissey DJ, Naviliat-Cuncic O, Redshaw M, Ringle R, Sandler R, Schwarz S, Sumithrarachchi CS, Valverde AA, Villari ACC. High Precision Determination of the β Decay Q(EC) Value of (11)C and Implications on the Tests of the Standard Model. Phys Rev Lett 2016; 116:012501. [PMID: 26799013 DOI: 10.1103/physrevlett.116.012501] [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: 09/24/2015] [Indexed: 06/05/2023]
Abstract
We report the determination of the Q(EC) value of the mirror transition of (11)C by measuring the atomic masses of (11)C and (11)B using Penning trap mass spectrometry. More than an order of magnitude improvement in precision is achieved as compared to the 2012 Atomic Mass Evaluation (Ame2012) [Chin. Phys. C 36, 1603 (2012)]. This leads to a factor of 3 improvement in the calculated Ft value. Using the new value, Q(EC)=1981.690(61) keV, the uncertainty on Ft is no longer dominated by the uncertainty on the Q(EC) value. Based on this measurement, we provide an updated estimate of the Gamow-Teller to Fermi mixing ratio and standard model values of the correlation coefficients.
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Affiliation(s)
- K Gulyuz
- National Superconducting Cyclotron Laboratory, East Lansing, Michigan 48824, USA
| | - G Bollen
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
- Facility for Rare Isotope Beams, East Lansing, Michigan 48824, USA
| | - M Brodeur
- Department of Physics, University of Notre Dame, Notre Dame, Indiana 46556, USA
| | - R A Bryce
- Department of Physics, Central Michigan University, Mount Pleasant, Michigan 48859, USA
| | - K Cooper
- National Superconducting Cyclotron Laboratory, East Lansing, Michigan 48824, USA
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, USA
| | - M Eibach
- National Superconducting Cyclotron Laboratory, East Lansing, Michigan 48824, USA
| | - C Izzo
- National Superconducting Cyclotron Laboratory, East Lansing, Michigan 48824, USA
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - E Kwan
- National Superconducting Cyclotron Laboratory, East Lansing, Michigan 48824, USA
| | - K Manukyan
- Department of Physics, University of Notre Dame, Notre Dame, Indiana 46556, USA
| | - D J Morrissey
- National Superconducting Cyclotron Laboratory, East Lansing, Michigan 48824, USA
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, USA
| | - O Naviliat-Cuncic
- National Superconducting Cyclotron Laboratory, East Lansing, Michigan 48824, USA
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - M Redshaw
- National Superconducting Cyclotron Laboratory, East Lansing, Michigan 48824, USA
- Department of Physics, Central Michigan University, Mount Pleasant, Michigan 48859, USA
| | - R Ringle
- National Superconducting Cyclotron Laboratory, East Lansing, Michigan 48824, USA
| | - R Sandler
- National Superconducting Cyclotron Laboratory, East Lansing, Michigan 48824, USA
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - S Schwarz
- National Superconducting Cyclotron Laboratory, East Lansing, Michigan 48824, USA
| | - C S Sumithrarachchi
- National Superconducting Cyclotron Laboratory, East Lansing, Michigan 48824, USA
| | - A A Valverde
- National Superconducting Cyclotron Laboratory, East Lansing, Michigan 48824, USA
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - A C C Villari
- Facility for Rare Isotope Beams, East Lansing, Michigan 48824, USA
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Gaudefroy L, Mittig W, Orr NA, Varet S, Chartier M, Roussel-Chomaz P, Ebran JP, Fernández-Domínguez B, Frémont G, Gangnant P, Gillibert A, Grévy S, Libin JF, Maslov VA, Paschalis S, Pietras B, Penionzhkevich YE, Spitaels C, Villari ACC. Direct mass measurements of 19B, 22C, 29F, 31Ne, 34Na and other light exotic nuclei. Phys Rev Lett 2012; 109:202503. [PMID: 23215476 DOI: 10.1103/physrevlett.109.202503] [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: 03/01/2012] [Revised: 07/27/2012] [Indexed: 06/01/2023]
Abstract
We report on direct time-of-flight based mass measurements of 16 light neutron-rich nuclei. These include the first determination of the masses of the Borromean drip-line nuclei (19)B, (22)C, and (29)F as well as that of (34)Na. In addition, the most precise determinations to date for (23)N and (31)Ne are reported. Coupled with recent interaction cross-section measurements, the present results support the occurrence of a two-neutron halo in (22)C, with a dominant ν2s(1/2)(2) configuration, and a single-neutron halo in (31)Ne with the valence neutron occupying predominantly the 2p(3/2) orbital. Despite a very low two-neutron separation energy the development of a halo in (19)B is hindered by the 1d(5/2)(2) character of the valence neutrons.
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Affiliation(s)
- L Gaudefroy
- GANIL, CEA/DSM-CNRS/IN2P3, BP 55027, F-14076 Caen, France.
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8
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Gaubert G, Bieth C, Bougy W, Brionne N, Donzel X, Sineau A, Vallerand C, Villari ACC, Chaves C, Gamboni T, Geerts W, Giorginis G, Lövestam G, Mondelaers W. Microgan electron cyclotron resonance ion source in a Van de Graaff accelerator terminal. Rev Sci Instrum 2012; 83:02A340. [PMID: 22380187 DOI: 10.1063/1.3673005] [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] [Indexed: 05/31/2023]
Abstract
The Van de Graaff accelerator at IRMM works since many years providing proton, deuteron, and helium beams for nuclear data measurements. The original ion source was of RF type with quartz bottle. This kind of source, as well known, needs regular maintenance for which the accelerator tank must be completely opened. The heavy usage at high currents of the IRMM accelerator necessitated an opening about once every month. In 2010, the full permanent magnet Microgan electron cyclotron resonance (ECR) ion source from PANTECHNIK was installed into a new terminal platform together with a solid state amplifier of 50 W, a dedicated dosing system for 4 gases (with respective gas bottles H(2), D(2), He, and Ar), and a set of dedicated power supplies and electronic devices for the remote tuning of the source. The new system shows a very stable behaviour of the produced beam allowing running the Van de Graaf without maintenance for several months. This contribution will describe the full installed system in details (working at high pressure in the terminal, spark effects, and optic of the extraction), as well as beam results in dc or pulsed mode.
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Gaubert G, Bieth C, Bougy W, Brionne N, Donzel X, Leroy R, Sineau A, Vallerand C, Villari ACC, Thuillier T. Pantechnik new superconducting ion source: PantechniK Indian Superconducting Ion Source. Rev Sci Instrum 2012; 83:02A344. [PMID: 22380191 DOI: 10.1063/1.3673635] [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] [Indexed: 05/31/2023]
Abstract
The new ECR ion source PantechniK Indian Superconducting Ion Source (PKISIS) was recently commissioned at Pantechnik. Three superconducting coils generate the axial magnetic field configuration, while the radial magnetic field is done with the multi-layer permanent magnets. Special care was devoted to the design of the hexapolar structure, allowing a maximum magnetic field of 1.32 T at the wall of the 82 mm diameter plasma chamber. The three superconducting coils using low temperature superconducting wires are cooled by a single double stage cryo-cooler (4.2 K). Cryogen-free technology is used, providing reliability and easy maintenance at low cost. The maximum installed RF power (18.0 GHz) is of 2 kW. Metallic beams can be produced with an oven (T(max) = 1400 °C) installed with an angle of 5° with respect to the source axis or a sputtering system, mounted on the axis of the source. The beam extraction system is constituted of three electrodes in accel-decel configuration. The new source of Pantechnik is conceived for reaching optimum performances at 18 GHz RF frequencies. PKISIS magnetic fields are 2.1 T axial B(inj) and 1.32 T radial field in the wall, variable B(min) with an independent coil and a large and opened extraction region. Moreover, PKISIS integrates modern design concepts, like RF direct injection (2 kW availability), dc-bias moving disk, out-of-axis oven and axial sputtering facility for metal beams. Finally, PKISIS is also conceived in order to operate in a high-voltage platform with minor power consumption.
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10
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Schiffer JP, Freeman SJ, Clark JA, Deibel C, Fitzpatrick CR, Gros S, Heinz A, Hirata D, Jiang CL, Kay BP, Parikh A, Parker PD, Rehm KE, Villari ACC, Werner V, Wrede C. Nuclear structure relevant to neutrinoless double beta decay: 76Ge and 76Se. Phys Rev Lett 2008; 100:112501. [PMID: 18517778 DOI: 10.1103/physrevlett.100.112501] [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: 10/02/2007] [Indexed: 05/26/2023]
Abstract
The possibility of observing neutrinoless double beta decay offers the opportunity of determining the effective neutrino mass if the nuclear matrix element were known. Theoretical calculations are uncertain, and measurements of the occupations of valence orbits by nucleons active in the decay can be important. The occupation of valence neutron orbits in the ground states of 76Ge (a candidate for such decay) and 76Se (the daughter nucleus) were determined by precisely measuring cross sections for both neutron-adding and removing transfer reactions. Our results indicate that the Fermi surface is much more diffuse than in theoretical calculations. We find that the populations of at least three orbits change significantly between these two ground states while in the calculations, the changes are confined primarily to one orbit.
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Affiliation(s)
- J P Schiffer
- Physics Division, Argonne National Laboratory, Argonne, IL 60439, USA.
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11
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Eléon C, Gaubert G, Jardin P, Saint-Laurent MG, Alcantara J, Alvès Condé R, Barué C, Boilley D, Cornell JC, Delahaye P, Dubois M, Jacquot B, Leherissier P, Leroy R, Lhersonneau G, Marie-Jeanne M, Maunoury L, Pacquet JY, Pellemoine F, Pierret C, Thomas JC, Villari ACC. Development of a 1+/N+ setup for the production of multicharged radioactive alkali ions in SPIRAL. Rev Sci Instrum 2008; 79:02A904. [PMID: 18315159 DOI: 10.1063/1.2819738] [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] [Indexed: 05/26/2023]
Abstract
In the framework of the production of radioactive ion beams by the isotope separator online method, a new system has been developed at GANIL/SPIRAL I to produce multicharged alkali ions. The principle, referred to as the "direct 1+/N+ method," consists of a surface ionization source associated with a multicharged electron-cyclotron-resonance ion source without an intermediate mass separator. This new system has been tested online using a (48)Ca primary beam at 60.3 A MeV. The experimental evidence of the direct 1+/N+ process has been obtained for a potential difference between the two sources of 11 V and with a 1+/N+ charge breeding efficiency of 0.04% for (47)K(5+). This value is significantly lower than the value of 6% obtained for stable K ions with the standard 1+/N+ method. A possible explanation is given in the text.
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Affiliation(s)
- C Eléon
- GANIL CEA/DSN-CNRS/IN2P3, Bd H Becquerel, BP 55027, Caen Cedex 5, France.
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12
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Mueller P, Sulai IA, Villari ACC, Alcántara-Núñez JA, Alves-Condé R, Bailey K, Drake GWF, Dubois M, Eléon C, Gaubert G, Holt RJ, Janssens RVF, Lecesne N, Lu ZT, O'Connor TP, Saint-Laurent MG, Thomas JC, Wang LB. Nuclear charge radius of 8He. Phys Rev Lett 2007; 99:252501. [PMID: 18233516 DOI: 10.1103/physrevlett.99.252501] [Citation(s) in RCA: 7] [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: 11/21/2007] [Indexed: 05/25/2023]
Abstract
The root-mean-square (rms) nuclear charge radius of 8He, the most neutron-rich of all particle-stable nuclei, has been determined for the first time to be 1.93(3) fm. In addition, the rms charge radius of 6He was measured to be 2.068(11) fm, in excellent agreement with a previous result. The significant reduction in charge radius from 6He to 8He is an indication of the change in the correlations of the excess neutrons and is consistent with the 8He neutron halo structure. The experiment was based on laser spectroscopy of individual helium atoms cooled and confined in a magneto-optical trap. Charge radii were extracted from the measured isotope shifts with the help of precision atomic theory calculations.
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Affiliation(s)
- P Mueller
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA.
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Savard G, Buchinger F, Clark JA, Crawford JE, Gulick S, Hardy JC, Hecht AA, Lee JKP, Levand AF, Scielzo ND, Sharma H, Sharma KS, Tanihata I, Villari ACC, Wang Y. Q value of the superallowed decay of 46V and its influence on Vud and the unitarity of the Cabibbo-Kobayashi-Maskawa matrix. Phys Rev Lett 2005; 95:102501. [PMID: 16196923 DOI: 10.1103/physrevlett.95.102501] [Citation(s) in RCA: 2] [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: 04/15/2005] [Indexed: 05/04/2023]
Abstract
The masses of the radioactive nuclei (46)V and its decay daughter (46)Ti have been measured with the Canadian Penning Trap on-line Penning trap mass spectrometer to a precision of 1 x 10(-8). A Q(EC) value of 7052.90(40) keV for the superallowed beta decay of (46)V is obtained from the difference of these two masses. With this precise Q value, the Ft value for this decay is determined with improved precision. An investigation of an earlier Q-value measurement for (46)V uncovers a set of 7 measurements that cannot be reconciled with modern data and affects previous evaluations of V(ud) from superallowed Fermi decays. A new evaluation, adding our new data and removing the discredited subset, yields new values for G(V) and V(ud). When combined with recent results for V(us), this yields modified constraints for the unitarity of the Cabibbo-Kobayashi-Maskawa matrix and other extensions of the standard model.
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Affiliation(s)
- G Savard
- Physics Division, Argonne National Laboratory, Illinois 60439, USA
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