C. Gaulard | Paris Sud XI University (original) (raw)

Papers by C. Gaulard

EPJ Web of Conferences, 2014

ABSTRACT Using the On-Line Nuclear Orientation method, POLAREX (POLARization of EXotic nuclei) is... more ABSTRACT Using the On-Line Nuclear Orientation method, POLAREX (POLARization of EXotic nuclei) is a new facility allowing to study the anisotropic decay of spin-oriented nuclei. Based on the combination of on-line implantation of radioactive nuclei with Low Temperature Nuclear Orientation technique and Nuclear Magnetic Resonance, POLAREX allows to measure nuclear electromagnetic moments and ground-state spins, in the aim to get information about the wave function composition of the nuclear state. Polarized nuclei can also be used to study fundamental interactions involving nuclear β-decay asymmetries. The POLAREX infrastructure will be installed at Accélérateur Linéaire auprés du Tandem d'Orsay in order to study neutron-rich nuclei, some of which have not been studied yet. Will be presented here, all the possibilities of this new facility and a non exhaustive scientific program.

Physics Letters B, 2011

We have measured the spectroscopic quadrupole moment of the 6− isomeric state in 66Cu to be |Qs|=... more We have measured the spectroscopic quadrupole moment of the 6− isomeric state in 66Cu to be |Qs|=18.6(12) efm2. This state results from a weak coupling of the πp3/2 and the νg9/2 orbitals, which lead to sizable deformation at oblate and prolate shapes, correspondingly, in the 68Ni region. The interplay between these two different deformation-driving orbitals is observed at N=37 for

Physical Review Letters, 2008

The extended radius of a halo nuclide is very sensitive to the minute binding energy of its valen... more The extended radius of a halo nuclide is very sensitive to the minute binding energy of its valence nucleons. The binding energy of Li11 has been measured with high precision by using the radio-frequency spectrometer MISTRAL at CERN&amp;amp;#39;s ISOLDE facility. The new two-neutron separation energy of 378±5keV is 25% higher than the previously accepted value with an uncertainty 5 times

Nuclear Physics A, 2009

... 91-22 (1991). [37] BM Young, W. Benenson, M. Fauerbach, JH Kelley, R. Pfaff, BM Sherrill, M. ... more ... 91-22 (1991). [37] BM Young, W. Benenson, M. Fauerbach, JH Kelley, R. Pfaff, BM Sherrill, M. Steiner, JS Winfield, T. Kubo, M. Hellstr m, NA Orr, J. Stetson, JA Winger, SJ Yennello, Phys. Rev. Lett. 71 (1993) 4124. [38] M. Smith ...

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1996

A polarized deuterium target internal to a medium-energy electron storage ring is described in th... more A polarized deuterium target internal to a medium-energy electron storage ring is described in the context of spindependent (e, e'd) and (e, e'p) experiments. Tensor polarized deuterium was produced in an atomic beam source and injected into a storage cell target. A Breit-Rabi polarimeter was used to monitor the injected atomic beam polarization. An electrostatic ion-extraction system and a Wien filter were utilized to measure on-tine the atomic fraction of the target gas (71 f 2%) in the storage cell. A target thickness t N 2 x 10 I3 'H/cm* was achieved. The target tensor polarization was varied from Pzt = 0.49( 3) to P,; = -0X9( 6) while keeping the vector polarization Pz at zero. The luminosity was N 2 x 103' e-. 2H. cm-2s-' at a beam current of 120 mA. The performance was stable over a five-week running period. A large acceptance non-magnetic detector system was used for the electron-proton (deuteron) coincidence measurement. It is demonstrated that these techniques result in low backgrounds due to scattering from species other than the polarized target gas and allow for fast and flexible orientation of the target spin. Specific issues such as interfacing the experiment to the storage ring and monitoring the performance of the target system are discussed in detail.

International Journal of Mass Spectrometry, 2006

ABSTRACT At Princeton in the 1960’s, L.G. Smith invented an instrument of astonishing accuracy an... more ABSTRACT At Princeton in the 1960’s, L.G. Smith invented an instrument of astonishing accuracy and rapid measurement time, derived from his so-called mass synchrometer. Using the same principle, a radiofrequency spectrometer was constructed in Orsay to measure masses of the shortest-lived nuclides at Cern’s Isolde facility. Smith’s spectrometer is now a museum piece, making the Orsay version (since baptized, MISTRAL) the sole example of such an instrument and the only one ever to be used on-line. Here we report on a measurement of the 65 ms half-life, N=Z nuclide performed with MISTRAL. The measured mass excess of keV is compared with that obtained by ISOLTRAP, since independent measurements using different techniques assure a healthy gene pool for the recommended masses of the atomic mass evaluation. The nuclide is the heaviest for which a precise mass is of importance for the so-called Wigner energy. A discussion is presented concerning this Wigner energy, perhaps the last component of nuclear mass formulas resisting microscopic treatment.

$Research paper thumbnail of Measurement of beam-recoil observables Ox , Oz and target asymmetry T for the reaction $ \gamma$ p → K+ $ \Lambda$$

The European Physical Journal A, 2009

The European Physical Journal A, 2005

Neutral pion photoproduction has been measured from 550 to 1500 MeV with the GRAAL facility, loca... more Neutral pion photoproduction has been measured from 550 to 1500 MeV with the GRAAL facility, located at the ESRF in Grenoble. Differential cross-section and beam asymmetry have been measured over a wide angular range. These high-precision data improve significantly the database for the beam asymmetry in the second and third resonance regions covering for the first time the energy domain 1100-1500 MeV. New partial-wave analyses including these data are presented for which the beam asymmetry brings crucial constraints.

The European Physical Journal A, 2007

Beam asymmetry and differential cross section for the reaction γp→ ηp were measured from producti... more Beam asymmetry and differential cross section for the reaction γp→ ηp were measured from production threshold to 1500 MeV photon laboratory energy. The two dominant neutral decay modes of the η meson, η → 2γ and η → 3π 0 , were analyzed. The full set of measurements is in good agreement with previously published results. Our data were compared with three models. They all fit satisfactorily the results but their respective resonance contributions are quite different. The possible photoexcitation of a narrow state N(1670) was investigated and no evidence was found.

$Research paper thumbnail of High accuracy mass measurement of the very short-lived halo nuclide <math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msup><mrow></mrow><mn>11</mn></msup></mrow><annotation encoding="application/x-tex">^{11} </annotation></semantics></math>11 Li$

10th INTC Meeting, …, 2001

... 11 Li D. Lunney 1 , G. Audi 1 , C. Bachelet 1 , K. Blaum 2 , G. Bollen 3 , C. Gaulard 1 , S. ... more ... 11 Li D. Lunney 1 , G. Audi 1 , C. Bachelet 1 , K. Blaum 2 , G. Bollen 3 , C. Gaulard 1 , S. Henry 4 , F. Herfurth 5 , A. Kellerbauer 5 , A. Lépine-Szily 6 , M. de Saint Simon 1 , H. Simon 2 , C. Thibault 1 , N. Vieira 1 ... U e ta, M iy ak e & Bu nd (3-bo d y F add eev ), 1 999 C o b is, Fedo ...

Physics Letters B, 2000

S beam asymmetries for p q photoproduction on the proton have been measured in the energy range 5... more S beam asymmetries for p q photoproduction on the proton have been measured in the energy range 550-1100 MeV over a wide angular range. The statistical and systematic errors of the data are much lower than in previous measurements, due to the high polarization of the photon beam and the cylindrical geometry of the 4p detector. Our results confirm the 1 E-mail address: Capogni@ginevra.roma2.infn.it 2 E-mail address: Slava@cpc.inr.ac.ru, Slava@gravax2.in2p3.fr 0370-2693r00r$ -see front matter q 2000 Elsevier Science B.V. All rights reserved.