46 results on '"J. C. Zamora"'
Search Results
2. Digital Signal Analysis based on Convolutional Neural Networks for Active Target Time Projection Chambers.
- Author
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Guilherme Ferrari Fortino, J. C. Zamora, L. E. Tamayose, N. S. T. Hirata, and V. Guimaraes
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- 2022
3. Probing spin-isospin excitations in proton-rich nuclei via the C11(p,n)N11 reaction
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J. Schmitt, G. B. King, R. G. T. Zegers, Y. Ayyad, D. Bazin, B. A. Brown, A. Carls, J. Chen, A. Davis, M. DeNudt, J. Droste, B. Gao, C. Hultquist, H. Iwasaki, S. Noji, S. Pastore, J. Pereira, M. Piarulli, H. Sakai, A. Stolz, R. Titus, R. B. Wiringa, and J. C. Zamora
- Published
- 2022
4. Quasielastic scattering of light radioactive and stable projectiles on Be9
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U. Umbelino, R. Lichtenthäler, O. C. B. Santos, K. C. C. Pires, A. S. Serra, V. Scarduelli, A. L. de Lara, E. O. N. Zevallos, J. C. Zamora, A. Lépine-Szily, J. M. B. Shorto, M. Assunção, and V. A. B. Zagatto
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ESPALHAMENTO - Published
- 2022
5. Vanishing Vector Rotation in Quadric Geometric Algebra
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J. C. Zamora Esquivel
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Applied Mathematics - Published
- 2022
6. Role of direct mechanism in two-nucleon T=0 transfer reactions in light nuclei using the (Li6,α) probe
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J. C. Zamora, J. L. Ferreira, A. Barioni, E. N. Cardozo, D. Abriola, A. Arazi, M. Assunção, E. de Barbará, M. A. Cardona, V. Guimarães, D. Hojman, G. V. Martí, D. R. Mendes, A. J. Pacheco, K. C. C. Pires, D. Ramos, O. C. B. Santos, and J. Lubian
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- 2022
7. Evidence of a Near-Threshold Resonance in B11 Relevant to the β -Delayed Proton Emission of Be11
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Y. Ayyad, W. Mittig, T. Tang, B. Olaizola, G. Potel, N. Rijal, N. Watwood, H. Alvarez-Pol, D. Bazin, M. Caamaño, J. Chen, M. Cortesi, B. Fernández-Domínguez, S. Giraud, P. Gueye, S. Heinitz, R. Jain, B. P. Kay, E. A. Maugeri, B. Monteagudo, F. Ndayisabye, S. N. Paneru, J. Pereira, E. Rubino, C. Santamaria, D. Schumann, J. Surbrook, L. Wagner, J. C. Zamora, and V. Zelevinsky
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General Physics and Astronomy - Published
- 2022
8. Simulation of the RIBRAS Facility with GEANT4
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L. E. Tamayose, J. C. Zamora, G. F. Fortino, and D. Flechas
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Accelerator Physics (physics.acc-ph) ,Physics - Instrumentation and Detectors ,FOS: Physical sciences ,General Physics and Astronomy ,Physics - Accelerator Physics ,Instrumentation and Detectors (physics.ins-det) ,Nuclear Experiment (nucl-ex) ,Computational Physics (physics.comp-ph) ,Nuclear Experiment ,Physics - Computational Physics ,CAMPO MAGNÉTICO - Abstract
A Geant4 simulation code was developed to perform realistic simulations of the RIBRAS facility. A second order expansion of a finite solenoid field was included to describe the beam optics with a good precision. A systematic study of coil currents for several magnetic rigidities and focal points was performed. Parameterizations of the coil currents for single and dual mode operations were obtained. Dedicated routines were developed to simulate the mechanism of direct reactions involving two and three particles in the final state. The present simulations were employed to investigate the feasibility of a Solenoidal Spectrometer with the RIBRAS facility. Our first results indicate that the concept can be applied in the RIBRAS system under certain conditions. Forthcoming studies both from simulations and experiment are already under development.
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- 2022
9. New resonances in C11 above the B10 + p threshold investigated by inverse kinematic resonant scattering
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Gurpreet Kaur, V. Guimarães, J. C. Zamora, M. Assunção, J. Alcantara-Nunez, A. L. de Lara, E. O. N. Zevallos, J. B. Ribeiro, R. Lichtenthäler, K. C. C. Pires, O. C. B. Santos, V. Morcelle, and R. J. deBoer
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- 2022
10. R-matrix parameters evaluation for direct and indirect kinematics data using AZURE2
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J B Ribeiro, V Guimaraes, G Kaur, and J C Zamora
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History ,Computer Science Applications ,Education - Abstract
R-matrix analyses, using the code AZURE2, were performed for the 12C+p resonant scattering data obtained in direct and inverse kinematics. Proton energy spectra in the region of the first three excited states in 13N above the 12C+p threshold were analyzed. We used two kinds of statistics data treatment to evaluate the uncertainties of the energy and widths parameter of the resonances obtained from direct and inverse kinematics spectra. Both methods indicate smaller width uncertainties from analyses of the inverse kinematics data. The correlation coefficients between resonance widths differ considerably for the direct and inverse kinematics or when analyzing direct and inverse kinematics data simultaneously.
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- 2022
11. Investigation of the isoscalar response of Mg24 to Li6 scattering
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Shumpei Noji, G. Gey, Y. Yamamoto, L. Batail, S. Zhu, R. Titus, Eiji Ideguchi, P. von Neumann-Cosel, A. Inoue, J. C. Zamora, Hooi Jin Ong, J. Schmitt, Johann Isaak, M. P. Carpenter, Nori Aoi, T. H. Hoang, U. Garg, J. J. Carroll, V. Werner, X. K. Zhou, M. L. Liu, Takeshi Koike, Nobuyuki Kobayashi, C. Kacir, C. J. Guess, D. Bazin, Hisanori Fujita, R. G. T. Zegers, Chihiro Iwamoto, Sophie Péru, N. Ichige, C. Sullivan, Atsushi Tamii, S. Lipschutz, E. Hudson, J. Pereira, M.N. Harakeh, M. Kumar Raju, and Y. D. Fang
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Physics ,010308 nuclear & particles physics ,Scattering ,Isoscalar ,Nuclear Theory ,Resonance ,Inelastic scattering ,01 natural sciences ,Molecular physics ,0103 physical sciences ,Quadrupole ,010306 general physics ,Random phase approximation ,Ground state ,Multipole expansion - Abstract
Background: Mg 24 is a strongly deformed nucleus in the ground state. Deformation effects can be observed in the structure of the isoscalar giant monopole and quadrupole resonances. Mg 24 is also a nucleus that is well known to present different types of cluster-oscillation modes. Both giant resonances and cluster states are strongly populated by isoscalar transitions. Purpose: To extract the E 0 , E 1 , and E 2 transition strengths via Li 6 scattering. The Li 6 probe is a powerful tool for investigating the isoscalar nuclear response with a very favorable ratio of resonance-to-continuum background. Method: Double-differential cross sections of Li 6 inelastic scattering, at the beam energy of 100 MeV/u, were measured in the excitation-energy range 10 – 40 MeV and scattering angles 0 − 3 ∘ . A multipole-decomposition analysis was performed for extracting the isoscalar E 0 , E 1 , and E 2 strength distributions. Results: The extracted multipole strengths were compared with predictions from consistent quasiparticle random phase approximation calculations. The theoretical predictions are in fair agreement with the experimental data. The E 0 strength was also compared with results from antisymmetrized molecular dynamics calculations found in the literature. A few peaks in the experimental data might be associated with clustering in Mg 24 . Conclusions: Ground-state deformation effects were observed in the isoscalar giant monopole resonance (ISGMR) and isoscalar giant quadrupole resonance (ISGQR) distributions. The ISGMR strength is split in two peaks around 19 and 28 MeV. The ISGQR exhibits a pronounced peak at 20 MeV with a broadening at the low-energy region, similar to predictions from microscopic calculations. Signatures of excitation of cluster states were observed in the E 0 response. Further studies including particle-decay measurements will be required to confirm the nature of the observed peaks.
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- 2021
12. Evidence of the effect of strong stripping channels on the dynamics of the Li8+Ni58 reaction
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Juan Antonio Alcantara-Nunez, Valdir Guimaraes, O. C. B. Santos, U. Umbelino, M. C. Morais, Rubens Lichtenthäler, J. C. Zamora, Marlete Assunção, Viviane Morcelle, E. O. N. Zevallos, A. M. Moro, Jin Lei, Alinka Lepine-Szily, A. L. de Lara, P. N. de Faria, S. Appannababu, J. M. B. Shorto, V. A. B. Zagatto, A. Serra, Valdir Brunetti Scarduelli, Roberto Linares, A. Barioni, and K. C. C. Pires
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Physics ,Quasielastic scattering ,Stripping (chemistry) ,010308 nuclear & particles physics ,Nuclear Theory ,Dynamics (mechanics) ,Coupling (probability) ,Breakup ,01 natural sciences ,0103 physical sciences ,Neutron ,Continuum (set theory) ,Atomic physics ,Nuclear Experiment ,010306 general physics ,Energy (signal processing) - Abstract
The $^{8}\mathrm{Li}+^{58}\mathrm{Ni}$ collision is investigated at 23.9, 26.1, 28.7, and 30 MeV bombarding energies. Quasielastic angular distributions and the singles $^{7}\mathrm{Li}$ angular and energy distributions are presented. Coupled-reaction channels (CRC) calculations, which include the coupling of the elastic channel to $^{59}\mathrm{Ni}=^{58}\mathrm{Ni}\phantom{\rule{0.16em}{0ex}}+\phantom{\rule{0.16em}{0ex}}n$ states above and below the neutron threshold, provide a simultaneous description of the quasielastic and transfer distributions and evidence the strong effect of the one-neutron transfer/breakup channels on the quasielastic scattering. The $^{7}\mathrm{Li}$ angular and energy distributions have been also successfully analyzed combining the continuum discretized coupled channels (CDCC) method, for the elastic breakup, and the IAV model of Ichimura, Austern, and Vincent [Phys. Rev. C 32, 431 (1985)], for the nonelastic breakup. These calculations indicate that most of the $^{7}\mathrm{Li}$ yields are due to nonelastic breakup contributions (transfer), whereas elastic breakup plays a minor role.
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- 2021
13. Elastic scattering and breakup reactions of the proton drip-line nucleus B8 on Pb208 at 238 MeV
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Z. H. Gao, Jin Lei, X. X. Xu, Youhua Yang, Jian-Ling Lou, A. M. Moro, Zheng-Hang Sun, Kun Wang, J. S. Wang, Shan Jin, J. C. Zamora, Valdir Guimaraes, Zhen Bai, Xiaojuan Zhou, Q. Hu, Peng Ma, Hooi Jin Ong, Z. G. Hu, F. F. Duan, Gang Yang, X. Liu, Dan-Yang Pang, J. B. Ma, H. S. Xu, S.W. Xu, and Y. H. Zhang
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Physics ,Nuclear physics ,Elastic scattering ,medicine.anatomical_structure ,Proton ,010308 nuclear & particles physics ,0103 physical sciences ,medicine ,010306 general physics ,Breakup ,01 natural sciences ,Nucleus ,Line (formation) - Published
- 2021
14. Elastic scattering and breakup reactions of the proton drip-line nucleus B 8 on Pb 208 at 238 Me
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K. Wang, Y. Y. Yang, A. M. Moro, V. Guimarães, Jin Lei, D. Y. Pang, F. F. Duan, J. L. Lou, J. C. Zamora, J. S. Wang, Z. Y. Sun, H. J. Ong, X. Liu, S. W. Xu, J. B. Ma, P. Ma, Z. Bai, Q. Hu, X. X. Xu, Z. H. Gao, G. Yang, S. Y. Jin, Y. H. Zhang, X. H. Zhou, Z. G. Hu, H. S. Xu
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- 2021
- Full Text
- View/download PDF
15. Evidence of the effect of strong stripping channels on the dynamics of the Li 8 + Ni 58
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O. C. B. Santos, R. Lichtenthäler, K. C. C. Pires, U. Umbelino, E. O. N. Zevallos, A. L. de Lara, A. S. Serra, V. Scarduelli, J. Alcántara-Núñez, V. Guimarães, A. Lépine-Szily, J. C. Zamora, A. M. Moro, S. Appannababu, M. Assunção, A. Barioni, R. Linares, V. A. B. Zagatto, P. N. de Faria, M. C. Morais, V. Morcelle, J. M. B. Shorto, Jin Lei
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- 2021
- Full Text
- View/download PDF
16. First Direct Measurement of Mg22(α,p)Al25 and Implications for X-Ray Burst Model-Observation Comparisons
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J. S. Randhawa, J. C. Zamora, S. Beceiro-Novo, L. Carpenter, F. Ndayisabye, H Robert, Yassid Ayyad, J. J. Kolata, S Aguilar, Hendrik Schatz, H. Alvarez-Pol, Tan Ahn, Patrick O'Malley, Z. Meisel, C. Santamaria, D. Blankstein, D. W. Bardayan, W. Mittig, N. Watwood, J. Pereira, Marco Cortesi, D. Bazin, Panagiotis Gastis, J. K. Smith, M. R. Hall, T. Mijatović, D. Cortina-Gil, S. L. Henderson, and A Pierre
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Nuclear reaction ,Physics ,Active target ,Time projection chamber ,Astrophysics::High Energy Astrophysical Phenomena ,X-ray ,General Physics and Astronomy ,Astrophysics ,Atmospheric temperature range ,01 natural sciences ,Reaction rate ,Neutron star ,Orders of magnitude (time) ,0103 physical sciences ,010306 general physics - Abstract
Type-I x-ray bursts can reveal the properties of an accreting neutron star system when compared with astrophysics model calculations. However, model results are sensitive to a handful of uncertain nuclear reaction rates, such as ^{22}Mg(α,p). We report the first direct measurement of ^{22}Mg(α,p), performed with the Active Target Time Projection Chamber. The corresponding astrophysical reaction rate is orders of magnitude larger than determined from a previous indirect measurement in a broad temperature range. Our new measurement suggests a less-compact neutron star in the source GS1826-24.
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- 2020
17. Reexamination of isoscalar giant resonances in C12 and Nb93 through Li6 scattering
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J. C. Zamora, J. Schmitt, C. J. Guess, V. Werner, Shumpei Noji, G. Gey, Nobuyuki Kobayashi, Y. Yamamoto, S. Zhu, T. H. Hoang, I. Deloncle, L. Batail, R. Titus, D. Bazin, S. Péru, R. G. T. Zegers, X. K. Zhou, J. Pereira, E. Hudson, C. Kacir, U. Garg, Takeshi Koike, C. Sullivan, M. P. Carpenter, Atsushi Tamii, Nori Aoi, S. Lipschutz, Eiji Ideguchi, Hisanori Fujita, Hooi Jin Ong, M.N. Harakeh, A. Inoue, Johann Isaak, Chihiro Iwamoto, M. L. Liu, Y. D. Fang, J. J. Carroll, M. Kumar Raju, N. Ichige, and P. von Neumann-Cosel
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Mass number ,Physics ,010308 nuclear & particles physics ,Scattering ,Isoscalar ,Magnetic monopole ,Nuclear structure ,Resonance ,01 natural sciences ,Excited state ,0103 physical sciences ,Sum rule in quantum mechanics ,Atomic physics ,Nuclear Experiment ,010306 general physics - Abstract
Inelastic ${}^{6}$Li scattering at 100 MeV/u on ${}^{12}$C and ${}^{93}$Nb have been measured with the high-resolution magnetic spectrometer Grand Raiden. The magnetic-rigidity settings of the spectrometer covered excitation energies from 10 to 40 MeV and scattering angles in the range $0^\circ < \theta_{\text{lab.}}< 2^\circ$. The isoscalar giant monopole resonance was selectively excited in the present data. Measurements free of instrumental background and the very favorable resonance-to-continuum ratio of ${}^{6}$Li scattering allowed for precise determination of the $E0$ strengths in ${}^{12}$C and ${}^{93}$Nb. It was found that the monopole strength in ${}^{12}$C exhausts $52 \pm 3^\text{(stat.)} \pm 8 ^\text{(sys.)}$\% of the energy-weighted sum rule (EWSR), which is considerably higher than results from previous $\alpha$-scattering experiments. The monopole strength in ${}^{93}$Nb exhausts $92 \pm 4^\text{(stat.)} \pm 10 ^\text{(sys.)}$\% of the EWSR, and it is consistent with measurements of nuclei with mass number of $A\approx90$. Such comparison indicates that the isoscalar giant monopole resonance distributions in these nuclei are very similar, and no influence due to nuclear structure was observed.
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- 2020
18. Erratum: Inverse-kinematics proton scattering from S42,44,P41,43 , and the collapse of the N=28 major shell closure [Phys. Rev. C 100 , 044312 (2019)]
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Eric Lunderberg, Alexander Volya, E. B. Haldeman, L. A. Riley, M. A. Liggett, L. M. Skiles, Brenden Longfellow, Alexandra Gade, J. C. Zamora, R. G. T. Zegers, S. D. Gregory, K. W. Kemper, D. Weisshaar, D. Bazin, P. C. Bender, B. A. Brown, J. Belarge, S. Lipschutz, Brandon Elman, J. Pereira, B. R. Klybor, T. Mijatović, P. D. Cottle, and R. Titus
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Physics ,Inverse kinematics ,Proton scattering ,Quantum electrodynamics ,Shell (structure) ,Closure (topology) ,Collapse (topology) - Published
- 2020
19. Gamow-Teller transitions to Zr93 via the Nb93(t,He3+γ ) reaction at 115 MeV/u and its application to the stellar electron-capture rates
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D. Bazin, Shumpei Noji, Panagiotis Gastis, J. Pereira, P. C. Bender, R. Titus, C. J. Guess, Kenjiro Miki, J. C. Zamora, T. N. Ginter, S. Lipschutz, A. Falduto, R. G. T. Zegers, D. Weisshaar, J. Schmitt, B. Gao, H. L. Crawford, Alexandra Gade, E. M. Ney, B. A. Brown, Jonathan Engel, Brenden Longfellow, C. Sullivan, and A. O. Macchiavelli
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Physics ,Nuclear physics ,Supernova ,Distribution (mathematics) ,Electron capture ,Double beta decay ,Nuclear Theory ,Quasiparticle ,Fermi energy ,Energy (signal processing) ,Excitation - Abstract
Electron-capture reactions play important roles in the late evolution of core-collapse supernovae. The electron-capture rates used in astrophysical simulations rely on theoretical calculations which have to be tested against and guided by experimental data. We report on the measurement of the Gamow-Teller strength distribution of the odd-mass nucleus $^{93}\mathrm{Nb}$ via the ($t,^{3}\mathrm{He}$ + $\ensuremath{\gamma}$) charge-exchange reaction at a beam energy of 115 MeV/u. The Gamow-Teller strength distributions were extracted up to an excitation energy in $^{93}\mathrm{Zr}$ of 10 MeV. The results were compared with shell-model and quasiparticle random-phase approximation (QRPA) calculations. The theoretical calculations fail to describe the details of the strength distribution, but estimate reasonably well the integrated Gamow-Teller transition strength. Electron-capture rates derived from the measured and theoretical strength distributions match reasonably well, especially at the higher stellar densities of importance for deleptonization during the collapse of the stellar core, since the electron-capture $Q$ value is close to zero and the Fermi energy sufficiently high to ensure that the details of the strength distribution do not have a strong impact on the derived rates. At stellar densities in excess of ${10}^{9}$ g/${\mathrm{cm}}^{3}$, the electron-capture rate based on a single-state approximation used in astrophysical simulations is slightly higher than the rates based on the data and the shell-model and QRPA calculations, likely due to the fact that the approximation includes temperature-dependent effects, which increase the rates. However, the difference is much smaller than that observed in recent studies of nuclei with $Zl40$ near $N=50$, suggesting that the single-state approximation does not account for Pauli-blocking effects for nuclei with $Zl40$ that are much stronger than those for $^{93}\mathrm{Nb}$ with $Z=41$.
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- 2020
20. Axenic culture and biosynthesis of secondary compounds in lichen symbiotic fungi, the Parmeliaceae
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Solenn Ferron, J. C. Zamora, F Le Dévéhat, Aurélie Sauvager, E. M. Díaz, María del Carmen Molina, Ana Crespo, Pradeep K. Divakar, Joël Boustie, Constantino Ruibal, M. Chollet, Natalia González-Benítez, Universidad Rey Juan Carlos [Madrid] (URJC), Universidad Complutense de Madrid = Complutense University of Madrid [Madrid] (UCM), Institut des Sciences Chimiques de Rennes (ISCR), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), Spanish Ministerio de Ciencia e InnovacionInstituto de Salud Carlos IIISpanish Government [CGL2013-42498-P, PID2019-105312GB-I00], Santander-Universidad Complutense de Madrid [PR75/18-21,605, PR 87/19-22,637, G/6400100/3000], Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Ciència de Materials de Barcelona (ICMAB), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), and This study was supported by the Spanish Ministerio de Ciencia e Innovacion (CGL2013–42498-P, PID2019-105312GB-I00) and the Santander-Universidad Complutense de Madrid (PR75/18–21,605, PR 87/19–22,637 and G/6400100/3000).
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0106 biological sciences ,0301 basic medicine ,Usnea ,ved/biology.organism_classification_rank.species ,Bioactive molecules ,01 natural sciences ,Axenic culture ,Platismatia ,03 medical and health sciences ,chemistry.chemical_compound ,Parmeliaceae ,Botany ,[CHIM]Chemical Sciences ,Axenic ,2. Zero hunger ,biology ,ved/biology ,fungi ,Usnic acid ,axenic culture mycobiont ontogeny ,biology.organism_classification ,Mycobiont ,Phenolic compounds ,Thallus ,030104 developmental biology ,chemistry ,ontogeny ,Parmelia saxatilis ,Tiliacea ,General Agricultural and Biological Sciences ,010606 plant biology & botany - Abstract
International audience; Lichens produce unique secondary metabolites with a rich potential as bioactive compounds. In many cases, the use of these molecules is limited by the low concentration of these compounds in thalli, low growth rate in culture, and changes in chemical patterns between thalli and aposymbiotic culture. In addition, the massive collection of some species of industrial interest can cause damage to lichen diversity and the associated environment. Six lichenized fungi (Arctoparmelia centrifuga, Parmelia saxatilis, Parmelina tiliacea, Platismatia glauca, Xanthoparmelia tinctina, and Usnea ghattensis) with biotechnological interest and belonging to Parmeliaceae have been cultured in order to test culture conditions and obtain enough biomass for further studies. In addition, we analyzed the compounds synthetized in axenic conditions and they were compared with chemosyndromes identified in complete thalli. Arctoparmelia centrifuga, P. saxatilis, P. tiliacea and X. tinctina were successfully cultivated while for P. glauca and U. ghattensis we only obtained sporulation and germination of the spores. The chemical pattern of the compounds secreted into the culture media varied significantly from the chemosyndrome of the whole thallus. Phenolic compounds of pharmacological and industrial interest (usnic acid, aspicilin, alpha-alectoronic acid, physodic acid, lobaric acid and nordivaricatic acid) and a wide variety of potentially bioactive compounds were obtained during the culture process.
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- 2020
21. Direct fusion measurement of the 8B proton-halo nucleus at near-barrier energies
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S. Ahn, H. Jayatissa, S. Upadhyayula, C. Hunt, A. Bosh, Antti Saastamoinen, R. O’Dwyer, E. Aboud, S. M. Lukyanov, Joshua Hooker, Valdir Guimaraes, Yu. E. Penionzhkevich, J. Bishop, M. Barbui, E. N. Cardozo, Brian Roeder, Grigory Rogachev, J. Lubian, J. C. Zamora, E. Koshchiy, and Marlete Assunção
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Physics ,Active target ,Excitation function ,Nuclear and High Energy Physics ,Fusion ,ELETROSTÁTICA ,Proton ,010308 nuclear & particles physics ,Coulomb barrier ,Halo nucleus ,01 natural sciences ,Molecular physics ,lcsh:QC1-999 ,Cross section (physics) ,0103 physical sciences ,010306 general physics ,lcsh:Physics - Abstract
Direct measurements of the total fusion cross section for B 8 + 40 Ar were achieved with the active target technique. The fusion excitation function was extracted at energies near the Coulomb barrier. The cross section is well described by a coupled reaction channels calculation. The data were compared with previous B 8 fusion experiments on Si 28 and Ni 58 targets. No evidence of striking enhancement of the total fusion cross section at near the Coulomb barrier, that was previously reported for the B 8 + 58 Ni system, was observed in these direct measurements. The present data are systematically consistent with the results for B 8 + 28 Si at higher energies and with other weakly-bound systems at near-barrier energies.
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- 2021
22. First measurement of isoscalar giant resonances in a stored-beam experiment
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I. Dillmann, V. K. Eremin, J. C. Zamora, M. Thürauf, Helmut Weick, M. Mahjour-Shafiei, Manfred Mutterer, Hans Geissel, S. Bagchi, Peter Egelhof, M. Kuilman, M. A. Najafi, D. Nagae, P. J. Woods, Tomohiro Uesaka, Catherine Rigollet, Yu. A. Litvinov, Takayuki Yamaguchi, Th. Kröll, Roman Gernhäuser, C. Nociforo, B. Streicher, Christoph Scheidenberger, Sergey Litvinov, M. Steck, C. Kozhuharov, F. Nolden, L. Stuhl, M.N. Harakeh, Danyal Winters, H. Kollmus, K. Yue, A.-L. Hartig, S. Ilieva, Santosh Roy, S. Bönig, M. Csatlós, Tatsuya Furuno, M. von Schmid, O. Kiselev, Nasser Kalantar-Nayestanaki, Thomas Aumann, Juzo Zenihiro, A. Krasznahorkay, U. Popp, J. S. Winfield, C. Dimopoulou, Research unit Nuclear & Hadron Physics, Theory of Condensed Matter, and Research unit Astroparticle Physics
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Nuclear reaction ,Nuclear and High Energy Physics ,Isoscalar ,Nuclear Theory ,01 natural sciences ,Nuclear physics ,INELASTIC ALPHA-SCATTERING ,ENERGY ,0103 physical sciences ,EXCITATION ,NI-58 ,PARTICLES ,Neutron ,ddc:530 ,010306 general physics ,Nuclear Experiment ,Physics ,NUCLEI ,010308 nuclear & particles physics ,Momentum transfer ,Resonance ,lcsh:QC1-999 ,Inverse kinematics ,Physics::Accelerator Physics ,Isoscalar giant resonances ,NEUTRON ,Sum rule in quantum mechanics ,DIPOLE RESONANCE ,Atomic physics ,Storage ring ,Beam (structure) ,lcsh:Physics ,MONOPOLE STRENGTH - Abstract
Physics letters / B 763, 16 - 19 (2016). doi:10.1016/j.physletb.2016.10.015, Published by North-Holland Publ., Amsterdam
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- 2016
23. Constraints for stellar electron-capture rates on Kr86 via the Kr86(t,He3+γ)Br86 reaction and the implications for core-collapse supernovae
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B. A. Brown, J. C. Zamora, J. Schmitt, Brandon Elman, Shumpei Noji, C. Sullivan, E. Lunderberg, Brenden Longfellow, T. Mijatović, R. G. T. Zegers, C. M. Campbell, D. Weisshaar, J. Pereira, J. Belarge, Jonathan Engel, D. Bazin, E. Kwan, P. C. Bender, S. Lipschutz, Bingshui Gao, R. Titus, Alexandra Gade, and E. M. Ney
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Physics ,010308 nuclear & particles physics ,Electron capture ,Gravitational wave ,Nuclear Theory ,01 natural sciences ,Nuclear physics ,Supernova ,Neutron number ,0103 physical sciences ,Quasiparticle ,Atomic number ,Neutrino ,010306 general physics ,Stellar density - Abstract
Author(s): Titus, R; Ney, EM; Zegers, RGT; Bazin, D; Belarge, J; Bender, PC; Brown, BA; Campbell, CM; Elman, B; Engel, J; Gade, A; Gao, B; Kwan, E; Lipschutz, S; Longfellow, B; Lunderberg, E; Mijatovic, T; Noji, S; Pereira, J; Schmitt, J; Sullivan, C; Weisshaar, D; Zamora, JC | Abstract: Background: In the late stages of stellar core collapse just prior to core bounce, electron captures on medium-heavy nuclei drive deleptonization. Therefore, simulations require the use of accurate reaction rates. Nuclei with neutron number near N=50 above atomic number Z=28 play an important role. Rates presently used in astrophysical simulations rely primarily on a relatively simple single-state approximation. In order to improve the accuracy of the astrophysical simulations, experimental data are needed to test the electron-capture rates and to guide the development of better theoretical models and astrophysical simulations. Purpose: The purpose of the present work was to measure the Gamow-Teller transition strength from Kr86 to Br86, to derive the stellar electron-capture rates based on the extracted strengths, and to compare the derived rates with rates based on shell-model and quasiparticle random-phase approximation (QRPA) Gamow-Teller strengths calculations, as well as the single-state approximation. An additional purpose was to test the impact of using improved electron-capture rates on the late evolution of core-collapse supernovae. Method: The Gamow-Teller strengths from Kr86 were extracted from the Kr86(t,He3+γ) charge-exchange reaction at 115MeV/u. The electron-capture rates were calculated as a function of stellar density and temperature. Besides the case of Kr86, the electron-capture rates based on the QRPA calculations were calculated for 78 additional isotopes near N=50 above Z=28. The impact of using these rates instead of those based on the single-state approximation is studied in a spherically symmetrical simulation of core collapse just prior to bounce. Results: The derived electron-capture rates on Kr86 from the experimental Gamow-Teller strength distribution are much smaller than the rates estimated based on the single-state approximation. Rates based on Gamow-Teller strengths estimated in shell-model and QRPA calculations are more accurate. The core-collapse supernova simulation with electron-capture rates based on the QRPA calculations indicate a significant reduction in the deleptonization during the collapse phase. Conclusions: It is important to utilize microscopic theoretical models that are tested by experimental data to constrain and estimate Gamow-Teller strengths and derived electron-capture rates for nuclei near N=50 that are inputs for astrophysical simulations of core-collapse supernovae and their multimessenger signals, such as the emission of neutrinos and gravitational waves.
- Published
- 2019
24. Inverse-kinematics proton scattering from S42,44, P41,43 , and the collapse of the N=28 major shell closure
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J. C. Zamora, Alexandra Gade, Alexander Volya, K. W. Kemper, R. G. T. Zegers, E. B. Haldeman, D. Weisshaar, M. A. Liggett, Brandon Elman, Brenden Longfellow, B. A. Brown, P. C. Bender, B. R. Klybor, P. D. Cottle, E. Lunderberg, J. Pereira, T. Mijatović, R. Titus, L. A. Riley, S. D. Gregory, J. Belarge, S. Lipschutz, L. M. Skiles, and D. Bazin
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Physics ,Matrix (mathematics) ,Closure (mathematics) ,010308 nuclear & particles physics ,Excited state ,Proton scattering ,0103 physical sciences ,Shell (structure) ,Collapse (topology) ,Atomic physics ,010306 general physics ,01 natural sciences - Abstract
Excited states of the neutron-rich isotopes $^{42,44}\mathrm{S}$ and $^{41,43}\mathrm{P}$ have been studied via inverse-kinematics proton scattering from a liquid hydrogen target, using the GRETINA $\ensuremath{\gamma}$-ray tracking array to extract inelastic-scattering cross sections. Deformation lengths of the ${2}_{1}^{+}$ excitations in $^{42,44}\mathrm{S}$ have been determined and, when combined with deformation lengths determined with electromagnetic probes, yield the ratio of neutron-to-proton matrix elements ${M}_{n}/{M}_{p}$ for the ${2}_{1}^{+}$ excitations in these nuclei. The present results for $^{41,43}\mathrm{P}(p,{p}^{\ensuremath{'}})$ are used to compare two shell-model interactions, SDPF-U and SDPF-MU. As in a recent study of $^{42}\mathrm{Si}$, the present results on $^{41,43}\mathrm{P}$ favor the SDPF-MU interaction.
- Published
- 2019
25. Experimental constraint on stellar electron-capture rates from the Sr88(t,He3+γ)Rb88 reaction at 115 MeV/u
- Author
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Jonathan Engel, J. C. Zamora, P. Gastis, E. M. Ney, H. L. Crawford, A. O. Macchiavelli, Alexandra Gade, Sam M. Austin, J. Schmitt, R. G. T. Zegers, Ashton Falduto, D. Weisshaar, R. Titus, C. J. Guess, P. C. Bender, B. Gao, D. Bazin, Kenjiro Miki, Shumpei Noji, T. N. Ginter, C. Sullivan, Brenden Longfellow, S. Lipschutz, J. Pereira, and B. A. Brown
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Physics ,010308 nuclear & particles physics ,Electron capture ,01 natural sciences ,Nuclear physics ,symbols.namesake ,Supernova ,Pauli exclusion principle ,Distribution (mathematics) ,0103 physical sciences ,Quasiparticle ,symbols ,010306 general physics ,Excitation ,Order of magnitude ,Energy (signal processing) - Abstract
The Gamow-Teller strength distribution from ${}^{88}$Sr was extracted from a $(t,{}^{3}\text{He}+\gamma)$ experiment at 115 MeV/$u$ to constrain estimates for the electron-capture rates on nuclei around $N=50$, between and including $^{78}$Ni and $^{88}$Sr, which are important for the late evolution of core-collapse supernovae. The observed strength below an excitation energy of 8 MeV was consistent with zero and below 10 MeV amounted to $0.1\pm0.05$. Except for a very-weak transition that could come from the 2.231-MeV $1^{+}$ state, no $\gamma$ lines that could be associated with the decay of known $1^{+}$ states were identified. The derived electron-capture rate from the measured strength distribution is more than an order of magnitude smaller than rates based on the single-state approximation presently used in astrophysical simulations for most nuclei near $N=50$. Rates based on shell-model and quasiparticle random-phase approximation calculations that account for Pauli blocking and core-polarization effects provide better estimates than the single-state approximation, although a relatively strong transition to the first $1^{+}$ state in $^{88}$Rb is not observed in the data. Pauli unblocking effects due to high stellar temperatures could partially counter the low electron-capture rates. The new data serves as a zero-temperature benchmark for constraining models used to estimate such effects.
- Published
- 2019
26. Phylogeny and character evolution in the
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J C, Zamora and S, Ekman
- Subjects
species delimitations ,Unilacryma ,coalescence analyses ,Dacryonaema ,cytology ,Dacrymycetes ,Carotenoids ,Research Article - Abstract
We present a multilocus phylogeny of the class Dacrymycetes, based on data from the 18S, ITS, 28S, RPB1, RPB2, TEF-1α, 12S, and ATP6 DNA regions, with c. 90 species including the types of most currently accepted genera. A variety of methodological approaches was used to infer phylogenetic relationships among the Dacrymycetes, from a supermatrix strategy using maximum likelihood and Bayesian inference on a concatenated dataset, to coalescence-based calculations, such as quartet-based summary methods of independent single-locus trees, and Bayesian integration of single-locus trees into a species tree under the multispecies coalescent. We evaluate for the first time the taxonomic usefulness of some cytological phenotypic characters, i.e., vacuolar contents (vacuolar bodies and lipid bodies), number of nuclei of recently discharged basidiospores, and pigments, with especial emphasis on carotenoids. These characters, along with several others traditionally used for the taxonomy of this group (basidium shape, presence and morphology of clamp connections, morphology of the terminal cells of cortical/marginal hyphae, presence and degree of ramification of the hyphidia), are mapped on the resulting phylogenies and their evolution through the class Dacrymycetes discussed. Our analyses reveal five lineages that putatively represent five different families, four of which are accepted and named. Three out of these four lineages correspond to previously circumscribed and published families (Cerinomycetaceae, Dacrymycetaceae, and Unilacrymaceae), and one is proposed as the new family Dacryonaemataceae. Provisionally, only a single order, Dacrymycetales, is accepted within the class. Furthermore, the systematics of the two smallest families, Dacryonaemataceae and Unilacrymaceae, are investigated to the species level, using coalescence-based species delimitation on multilocus DNA data, and a detailed morphological study including morphometric analyses of the basidiospores. Three species are accepted in Dacryonaema, the type, Da. rufum, the newly combined Da. macnabbii (basionym Dacrymyces macnabbii), and a new species named Da. macrosporum. Two species are accepted in Unilacryma, the new U. bispora, and the type, U. unispora, the latter treated in a broad sense pending improved sampling across the Holarctic.
- Published
- 2019
27. Constraining the Neutron Star Compactness: Extraction of the 23Al(p,γ) Reaction Rate for the rp Process
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C, Wolf, C, Langer, F, Montes, J, Pereira, W-J, Ong, T, Poxon-Pearson, S, Ahn, S, Ayoub, T, Baumann, D, Bazin, P C, Bender, B A, Brown, J, Browne, H, Crawford, R H, Cyburt, E, Deleeuw, B, Elman, S, Fiebiger, A, Gade, P, Gastis, S, Lipschutz, B, Longfellow, Z, Meisel, F M, Nunes, G, Perdikakis, R, Reifarth, W A, Richter, H, Schatz, K, Schmidt, J, Schmitt, C, Sullivan, R, Titus, D, Weisshaar, P J, Woods, J C, Zamora, and R G T, Zegers
- Abstract
The ^{23}Al(p,γ)^{24}Si reaction is among the most important reactions driving the energy generation in type-I x-ray bursts. However, the present reaction-rate uncertainty limits constraints on neutron star properties that can be achieved with burst model-observation comparisons. Here, we present a novel technique for constraining this important reaction by combining the GRETINA array with the neutron detector LENDA coupled to the S800 spectrograph at the National Superconducting Cyclotron Laboratory. The ^{23}Al(d,n) reaction was used to populate the astrophysically important states in ^{24}Si. This enables a measurement in complete kinematics for extracting all relevant inputs necessary to calculate the reaction rate. For the first time, a predicted close-lying doublet of a 2_{2}^{+} and (4_{1}^{+},0_{2}^{+}) state in ^{24}Si was disentangled, finally resolving conflicting results from two previous measurements. Moreover, it was possible to extract spectroscopic factors using GRETINA and LENDA simultaneously. This new technique may be used to constrain other important reaction rates for various astrophysical scenarios.
- Published
- 2019
28. Constraining the Neutron Star Compactness: Extraction of the Al23(p,γ) Reaction Rate for the rp Process
- Author
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B. A. Brown, Brenden Longfellow, Fernando Montes, J. Browne, Christoph Langer, P. Gastis, Eric Deleeuw, J. Schmitt, D. Bazin, H. L. Crawford, Konrad Schmidt, W. A. Richter, Alexandra Gade, W.-J. Ong, Philip Woods, Richard H. Cyburt, Rene Reifarth, P. C. Bender, Z. Meisel, J. Pereira, C. Wolf, C. Sullivan, R. Titus, Sara Ayoub, Brandon Elman, Thomas Baumann, J. C. Zamora, Francis M. F. Nunes, G. Perdikakis, S. Lipschutz, S. Ahn, R. G. T. Zegers, D. Weisshaar, T. Poxon-Pearson, Hendrik Schatz, and S. Fiebiger
- Subjects
Physics ,Chemical substance ,General Physics and Astronomy ,rp-process ,Type (model theory) ,01 natural sciences ,Nuclear physics ,Reaction rate ,Neutron star ,Compact space ,0103 physical sciences ,Neutron detection ,010306 general physics ,Spectrograph - Abstract
The ^{23}Al(p,γ)^{24}Si reaction is among the most important reactions driving the energy generation in type-I x-ray bursts. However, the present reaction-rate uncertainty limits constraints on neutron star properties that can be achieved with burst model-observation comparisons. Here, we present a novel technique for constraining this important reaction by combining the GRETINA array with the neutron detector LENDA coupled to the S800 spectrograph at the National Superconducting Cyclotron Laboratory. The ^{23}Al(d,n) reaction was used to populate the astrophysically important states in ^{24}Si. This enables a measurement in complete kinematics for extracting all relevant inputs necessary to calculate the reaction rate. For the first time, a predicted close-lying doublet of a 2_{2}^{+} and (4_{1}^{+},0_{2}^{+}) state in ^{24}Si was disentangled, finally resolving conflicting results from two previous measurements. Moreover, it was possible to extract spectroscopic factors using GRETINA and LENDA simultaneously. This new technique may be used to constrain other important reaction rates for various astrophysical scenarios.
- Published
- 2019
29. Effect of thousands of inelastic couplings on the elastic scattering channel
- Author
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Leandro Gasques, J. C. Zamora, and Luiz Carlos Chamon
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Elastic scattering ,Nuclear reaction ,Physics ,Nuclear and High Energy Physics ,Molecular physics ,Communication channel - Published
- 2020
30. Next-generation experiments with the Active Target Time Projection Chamber (AT-TPC)
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J. S. Randhawa, A. O. Macchiavelli, H. Alvarez-Pol, R. G. T. Zegers, Tan Ahn, Reynold J. Cooper, W. Mittig, C. Santamaria, L. Carpenter, N. Abgrall, Marco Cortesi, J. C. Zamora, S. Beceiro-Novo, N. Watwood, D. Bazin, B. Olaizola, and Y. Ayyad
- Subjects
Nuclear reaction ,Physics ,Nuclear and High Energy Physics ,Time projection chamber ,Luminosity (scattering theory) ,Physics::Instrumentation and Detectors ,010308 nuclear & particles physics ,Detector ,Inelastic scattering ,Tracking (particle physics) ,01 natural sciences ,Nuclear physics ,Recoil ,0103 physical sciences ,Nuclear Experiment ,010306 general physics ,Instrumentation ,Beam (structure) - Abstract
The Active Target Time Projection Chamber (AT-TPC) project at the National Superconducting Cyclotron Laboratory (NSCL) is a novel Active Target designed to study nuclear reactions induced by low-intensity exotic beams. The AT-TPC acts as a tracking medium and target at the same time, providing excellent angular (1 ° ) and energy resolution (3% FWHM) and high luminosity . The AT-TPC offers a broad range of applications within the low-energy nuclear physics domain. Resonant scattering and transfer reactions are typically performed with Active Targets using beams with energies spanning from 1 to 10 A MeV and with intensities as low as 100 pps. The AT-TPC is also a promising tool for experiments where the observables of interest require higher beam energies (above 100 A MeV ). In particular, inelastic scattering reactions on light targets, where the recoil particle has a very low kinetic energy (less than 1 MeV), can be performed with such a device. In this work, we discuss aspects of the AT-TPC experimental program, focusing on experiments that leverage the outstanding capabilities this detector offers. In addition, we introduce a conceptual design for a new Time Projection Chamber detector for specific measurements of reactions using special gases as targets.
- Published
- 2020
31. The ( Li6,Li*6[3.56MeV] ) reaction at 100 MeV/u as a probe of Gamow-Teller transition strengths in the inelastic scattering channel
- Author
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J. C. Zamora, Eiji Ideguchi, S. Zhu, Hooi Jin Ong, A. Inoue, R. G. T. Zegers, Takeshi Koike, T. H. Hoang, Atsushi Tamii, Shumpei Noji, Mohsen Harakeh, Chihiro Iwamoto, G. Gey, R. Titus, X. K. Zhou, Y. D. Fang, C. Kacir, M. L. Liu, S. Lipschutz, N. Ichige, Nobuyuki Kobayashi, M. Kumar Raju, J. Pereira, C. J. Guess, Johann Isaak, J. Schmitt, M. P. Carpenter, Nori Aoi, Sam M. Austin, D. Bazin, P. von Neumann-Cosel, Y. Yamamoto, C. Sullivan, J. J. Carroll, Hisanori Fujita, V. Werner, E. Hudson, and U. Garg
- Subjects
Physics ,Isovector ,010308 nuclear & particles physics ,Scattering ,Isoscalar ,Nuclear Theory ,Gamma ray ,Inelastic scattering ,01 natural sciences ,Nuclear physics ,0103 physical sciences ,r-process ,Neutrino ,Nuclear Experiment ,010306 general physics ,Excitation - Abstract
Background: Inelastic neutrino-nucleus scattering is important for understanding core-collapse supernovae and the detection of emitted neutrinos from such events in earth-based detectors. Direct measurement of the cross sections is difficult and has only been performed on a few nuclei. It is, therefore, important to develop indirect techniques from which the inelastic neutrino-nucleus scattering cross sections can be determined. Purpose: This paper presents a development of the (Li-6,Li-6*[T = 1, T-z = 0, 0(+), 3.56 MeV]) reaction at 100 MeV/u as a probe for isolating the isovector spin-transfer response in the inelastic channel (Delta S = 1, Delta T = 1, Delta T-z = 0) from which the Gamow-Teller transition strengths from nuclei of relevance for inelastic neutrino-nucleus scattering cross sections can be extracted. Method: By measuring the Li-6 ejectile in a magnetic spectrometer and selecting events in which the 3.56 MeV gamma ray from the decay of the Li-6*[3.56 MeV] state is detected, the isovector spin-transfer selectivity is obtained. High-purity germanium clover detectors served to detect the gamma rays. Doppler reconstruction was used to determine the gamma energy in the rest frame of Li-6. From the Li-6 and 3.56 MeV gamma-momentum vectors the excitation energy of the residual nucleus was determined. Results: In the study of the C-12(Li-6,Li-6*[3.56 MeV]) reaction, the isovector spin-transfer excitation-energy spectrum in the inelastic channel was successfully measured. The strong Gamow-Teller state in C-12 at 15.1 MeV was observed. Comparisons with the analog C-12(Li-6,He-6) reaction validate the method of extracting the Gamow-Teller strength. In measurements of the Mg-24, Nb-93(Li-6,Li-6*[3.56 MeV]) reactions, the 3.56 MeV gamma peak could not be isolated from the strong background in the gamma spectrum from the decay of the isoscalar excitations. It is argued that by using a gamma-ray tracking array instead of a clover array, it is feasible to extend the mass range over which the (Li-6,Li-6*) reaction can be used for extracting the isovector spin-transfer response up to mass numbers of similar to 25 and perhaps higher. Conclusions: It is demonstrated that the (Li-6,Li-6*[3.56 MeV]) reaction probe can be used to isolate the inelastic isovector spin-transfer response in nuclei. Application to nuclei with mass numbers of about 25 or more, however, will require a more efficient gamma-ray array with a better tracking capability.
- Published
- 2018
32. Evaluating methodologies for species delimitation: the mismatch between phenotypes and genotypes in lichenized fungi (
- Author
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C G, Boluda, V J, Rico, P K, Divakar, O, Nadyeina, L, Myllys, R T, McMullin, J C, Zamora, C, Scheidegger, and D L, Hawksworth
- Subjects
cryptic species ,haplotypes ,chemotypes ,species concepts ,speciation ,incomplete lineage sorting ,integrative taxonomy ,microsatellites ,Research Article - Abstract
In many lichen-forming fungi, molecular phylogenetic analyses lead to the discovery of cryptic species within traditional morphospecies. However, in some cases, molecular sequence data also questions the separation of phenotypically characterised species. Here we apply an integrative taxonomy approach – including morphological, chemical, molecular, and distributional characters – to re-assess species boundaries in a traditionally speciose group of hair lichens, Bryoria sect. Implexae. We sampled multilocus sequence and microsatellite data from 142 specimens from a broad intercontinental distribution. Molecular data included DNA sequences of the standard fungal markers ITS, IGS, GAPDH, two newly tested loci (FRBi15 and FRBi16), and SSR frequencies from 18 microsatellite markers. Datasets were analysed with Bayesian and maximum likelihood phylogenetic reconstruction, phenogram reconstruction, STRUCTURE Bayesian clustering, principal coordinate analysis, haplotype network, and several different species delimitation analyses (ABGD, PTP, GMYC, and DISSECT). Additionally, past population demography and divergence times are estimated. The different approaches to species recognition do not support the monophyly of the 11 currently accepted morphospecies, and rather suggest the reduction of these to four phylogenetic species. Moreover, three of these are relatively recent in origin and cryptic, including phenotypically and chemically variable specimens. Issues regarding the integration of an evolutionary perspective into taxonomic conclusions in species complexes, which have undergone recent diversification, are discussed. The four accepted species, all epitypified by sequenced material, are Bryoria fuscescens, B. glabra, B. kockiana, and B. pseudofuscescens. Ten species rank names are reduced to synonymy. In the absence of molecular data, they can be recorded as the B. fuscescens complex. Intraspecific phenotype plasticity and factors affecting the speciation of different morphospecies in this group of Bryoria are outlined.
- Published
- 2017
33. Low collectivity of the 21+ state of Po212
- Author
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K. Moschner, D. Kocheva, P. Van Isacker, P. Spagnoletti, A. Hennig, T. Schmidt, A. Vogt, Th. Kröll, K. A. Gladnishki, C. Müller-Gatermann, J. Litzinger, J. C. Zamora, P. Scholz, C. Fransen, V. Karayonchev, R. Altenkirch, A. Blazhev, J. Jolie, A. Astier, M. Djongolov, P. Petkov, M. Bast, Marcus Scheck, F. Diel, D. Wölk, S. Ansari, J. M. Keatings, K. O. Zell, V. Werner, E. Kluge, M. Cappellazzo, R. Stegmann, M. Beckers, Norbert Pietralla, Th. Braunroth, C. Stahl, A. Dewald, A. Goldkuhle, G. Rainovski, Alexander Stolz, N. Warr, and V. Yu. Ponomarev
- Subjects
Nuclear physics ,Physics ,010308 nuclear & particles physics ,0103 physical sciences ,State (functional analysis) ,010306 general physics ,01 natural sciences - Published
- 2017
34. Nuclear-matter radius studies from Ni58(α,α) experiments at the GSI Experimental Storage Ring with the EXL facility
- Author
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Hans Geissel, Tatsuya Furuno, Santosh Roy, C. Dimopoulou, U. Popp, J. S. Winfield, Takayuki Yamaguchi, Iris Dillmann, F. Nolden, M. Csatlós, Yu. A. Litvinov, Peter Egelhof, M. Kuilman, M.N. Harakeh, D. Nagae, B. Streicher, P. J. Woods, Th. Kroell, M. Steck, H. Kollmus, S. Boenig, L. Stuhl, O. Kiselev, M. A. Najafi, Juzo Zenihiro, M. Thuerauf, Tomohiro Uesaka, C. Scheidenberger, C. Nociforo, Nasser Kalantar-Nayestanaki, Thomas Aumann, K. Yue, A.-L. Hartig, Catherine Rigollet, S. Ilieva, C. Kozhuharov, Helmut Weick, M. Mahjour-Shafiei, S. Bagchi, J. C. Zamora, Danyal Winters, V. K. Eremin, Sergey Litvinov, A. Krasznahorkay, M. von Schmid, Manfred Mutterer, and Roman Gernhaeuser
- Subjects
Nuclear reaction ,Physics ,Elastic scattering ,010308 nuclear & particles physics ,chemistry.chemical_element ,Radius ,Nuclear matter ,01 natural sciences ,Eikonal approximation ,Ion ,Nuclear physics ,chemistry ,0103 physical sciences ,010306 general physics ,Helium ,Storage ring - Abstract
A novel method for measuring nuclear reactions in inverse kinematics with stored ion beams was successfully used to extract the nuclear-matter radius of $^{58}\mathrm{Ni}$. The experiment was performed at the experimental heavy-ion storage ring at the GSI facility using a stored $^{58}\mathrm{Ni}$ beam at energies of 100 and 150 MeV/u and an internal helium gas-jet target. Elastically scattered $\ensuremath{\alpha}$-recoils at low momentum transfers were measured with an in-ring detector system compatible with ultrahigh vacuum. Experimental angular distributions were fitted using density-dependent optical model potentials within the eikonal approximation. This permitted the extraction of the point-matter root-mean-square radius of $^{58}\mathrm{Ni}$ with an average value of 3.70(7) fm. Results from this work are in good agreement with several experiments performed in the past in normal kinematics. This pioneering experiment demonstrates a major breakthrough towards future investigations with far-from-stability stored beams using the present technique.
- Published
- 2017
35. Low collectivity of the first 2$^+$ states of $^{212,210}$Po
- Author
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A. Astier, A. Goldkuhle, C. Müller-Gatermann, F. Diel, D. Wölk, J. Litzinger, G. Rainovski, A. Dewald, P. Scholz, S. Ansari, Th. Braunroth, J. M. Keatings, A. Vogt, Alexander Stolz, J. Jolie, M. L. Cortés, V. Yu. Ponomarev, R. Altenkirch, C. Fransen, M. Stoyanova, Norbert Pietralla, A. Hennig, P. Spagnoletti, W. Witt, N. Warr, M. Spieker, T. Schmidt, A. Blazhev, K. O. Zell, E. Kluge, R. Stegmann, V. Karayonchev, M. Djongolov, M. Rudigier, P. Thöle, M. Beckers, M. Bast, C. Stahl, D. Kocheva, V. Werner, P. Petkov, Marcus Scheck, J. C. Zamora, Th. Kröll, K. Moschner, P. Van Isacker, M. Cappellazzo, K. A. Gladnishki, Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Physics ,History ,[PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th] ,010308 nuclear & particles physics ,Phonon ,Attenuation ,Yrast ,Shell (structure) ,[PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex] ,01 natural sciences ,Quasi particles ,Computer Science Applications ,Education ,symbols.namesake ,Recoil ,Excited state ,0103 physical sciences ,symbols ,Atomic physics ,010306 general physics ,Doppler effect - Abstract
International audience; The lifetimes of the first 2+ excited states of 212,210Po were measured in two transfer reactions 208Pb(12C,8Be)212Po and 208Pb(12C,10Be)210Po by the Recoil Distance Doppler Shift (RDDS) method and by the Doppler Shift Attenuation method (DSAM), respectively. The derived absolute B(E2) values of 2.6(3) W.u. for 212Po and 1.83(28) W.u. for 210Po indicate low collectivity. It is shown that the properties of the yrast , , and states in both nuclei cannot be described consistently in the framework of nuclear shell models. It is also demonstrated in the case of 210Po that Quasi-particle Phonon Model (QPM) calculations cannot overcome this problem thus indicating the existence of a peculiarity which is neglected in both theoretical approaches.
- Published
- 2017
36. Constraining the rp-process by measuring 23Al(d,n)24Si with GRETINA and LENDA at NSCL
- Author
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J. C. Zamora, Heather Crawford, Peter Bender, Daniel Bazin, Fernando Montes, Sara Ayoub, D. Weisshaar, Jaclyn Schmitt, Panagiotis Gastis, Eric Deleeuw, Christoph Langer, Brandon Elman, Rene Reifarth, C. Wolf, S. Lipschutz, Alex Brown, Justin Browne, Jorge Pereira, Alexandra Gade, Wei Jia Ong, Philip Woods, C. Sullivan, Brenden Longfellow, R. Titus, Konrad Schmidt, Filomena Nunes, Remco Zegers, Sunghoon Ahn, S. Fiebiger, T. Poxon-Pearson, G. Perdikakis, and Hendrik Schatz
- Subjects
Physics ,Astrophysics::High Energy Astrophysical Phenomena ,QC1-999 ,rp-process ,Tracking (particle physics) ,01 natural sciences ,7. Clean energy ,Nuclear physics ,Reaction rate ,Superconducting cyclotron ,Excited state ,0103 physical sciences ,Neutron detection ,Neutron ,010306 general physics ,Nuclear Experiment ,010303 astronomy & astrophysics ,Energy (signal processing) - Abstract
The 23 Al(p, γ)24 Si stellar reaction rate has a significant impact on the light-curve emitted in X-ray bursts. Theoretical calculations show that the reaction rate is mainly determined by the properties of direct capture as well as low-lying 2+ states and a possible 4+ state in 24 Si. Currently, there is little experimental information on the properties of these states.In this proceeding we will present a new experimental study to investigate this reaction, using the surrogate reaction 23 Al(d,n) at 47 AMeV at the National Superconducting Cyclotron Laboratory (NSCL). We will discuss our new experimental setup which allows us to use full kinematics employing the Gamma-Ray Energy Tracking In-beam Nuclear Array (GRETINA) to detect the γ-rays following the de-excitation of excited states of the reaction products and the Low Energy Neutron Detector Array (LENDA) to detect the recoiling neutrons. The S800 was used for identification of the 24 Si recoils. As a proof of principle to show the feasibility of this concept the Q-value spectrum of 22 Mg(d,n)23 Al is reconstructed.
- Published
- 2017
37. State of the art measurements with TexAT
- Author
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S. Upadhyayula, C. D. Pruitt, D. Jayatissa, Antti Saastamoinen, Curtis Hunt, E. C. Pollacco, M. Barbui, L. G. Sobotka, R. O’Dwyer, J. C. Zamora, Marlete Assunção, Brian Roeder, S. M. Lukyanov, E. Aboud, Grigory Rogachev, E. Koshchiy, Valdir Guimaraes, J. Bishop, A. Bosh, Joshua Hooker, S. Ahn, Yu. E. Penionzhkevich, E. Uberseder, Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay
- Subjects
Physics ,History ,010308 nuclear & particles physics ,business.industry ,Cyclotron ,Detector ,MicroMegas detector ,[PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex] ,7. Clean energy ,01 natural sciences ,Computer Science Applications ,Education ,law.invention ,Particle decay ,Cross section (physics) ,Optics ,Pixelation ,law ,Torr ,0103 physical sciences ,Electronics ,010306 general physics ,business - Abstract
In the past several years, there has been a large interest of Time Projection Chambers (TPCs) for use in experimental nuclear physics. This has continued in tandem with the requirement for high efficiency detectors with low intensity radioactive ion beams. TexAT is a Active Target TPC (AT-TPC) built at Texas A&M University utilizing MICRO MEsh GASeous (MicroMegas) pads and GET electronics developed specifically for TPCs. This design combines good TPC pixelation with a surrounding shell of Si/CsI telescopes to make an extremely versatile detector capable of a wide range of different experimental techniques with only minor modifications to the electronics setup. Two recent experiments performed at the Cyclotron Institute, Texas A&M University, are detailed here demonstrating versatility beyond the usual Thick Target Inverse Kinematics (TTIK) or transfer reactions that these TPCs are more typically used for. The first, a measurement of the 12N → 12C* → 3α decay demonstrates the capabilities of TexAT as a low-energy detector operating at low pressure (20 Torr) to measure β-delayed particle decay. The second, a direct measurement of the 8B+40Ar fusion cross section shows the advantages of operating in active target mode where the target also functions as the detector gas.
- Published
- 2019
38. Fungal Planet 471 – 21 December 2016
- Author
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P W, Crous, M J, Wingfield, T I, Burgess, G E St J, Hardy, C, Crane, S, Barrett, J F, Cano-Lira, J J, Le Roux, R, Thangavel, J, Guarro, A M, Stchigel, M P, Martín, D S, Alfredo, P A, Barber, R W, Barreto, I G, Baseia, J, Cano-Canals, R, Cheewangkoon, R J, Ferreira, J, Gené, C, Lechat, G, Moreno, F, Roets, R G, Shivas, J O, Sousa, Y P, Tan, N P, Wiederhold, S E, Abell, T, Accioly, J L, Albizu, J L, Alves, Z I, Antoniolli, N, Aplin, J, Araújo, M, Arzanlou, J D P, Bezerra, J-P, Bouchara, J R, Carlavilla, A, Castillo, V L, Castroagudín, P C, Ceresini, G F, Claridge, G, Coelho, V R M, Coimbra, L A, Costa, K C, da Cunha, S S, da Silva, R, Daniel, Z W, de Beer, M, Dueñas, J, Edwards, P, Enwistle, P O, Fiuza, J, Fournier, D, García, T B, Gibertoni, S, Giraud, M, Guevara-Suarez, L F P, Gusmão, S, Haituk, M, Heykoop, Y, Hirooka, T A, Hofmann, J, Houbraken, D P, Hughes, I, Kautmanová, O, Koppel, O, Koukol, E, Larsson, K P D, Latha, D H, Lee, D O, Lisboa, W S, Lisboa, Á, López-Villalba, J L N, Maciel, P, Manimohan, J L, Manjón, S, Marincowitz, T S, Marney, M, Meijer, A N, Miller, I, Olariaga, L M, Paiva, M, Piepenbring, J C, Poveda-Molero, K N A, Raj, H A, Raja, A, Rougeron, I, Salcedo, R, Samadi, T A B, Santos, K, Scarlett, K A, Seifert, L A, Shuttleworth, G A, Silva, M, Silva, J P Z, Siqueira, C M, Souza-Motta, S L, Stephenson, D A, Sutton, N, Tamakeaw, M T, Telleria, N, Valenzuela-Lopez, A, Viljoen, C M, Visagie, A, Vizzini, F, Wartchow, B D, Wingfield, E, Yurchenko, J C, Zamora, and J Z, Groenewald
- Subjects
ITS nrDNA barcodes ,LSU ,Fungal Planet description sheets ,novel fungal species ,systematics ,Research Article - Abstract
Novel species of fungi described in this study include those from various countries as follows: Australia: Apiognomonia lasiopetali on Lasiopetalum sp., Blastacervulus eucalyptorum on Eucalyptus adesmophloia, Bullanockia australis (incl. Bullanockia gen. nov.) on Kingia australis, Caliciopsis eucalypti on Eucalyptus marginata, Celerioriella petrophiles on Petrophile teretifolia, Coleophoma xanthosiae on Xanthosia rotundifolia, Coniothyrium hakeae on Hakea sp., Diatrypella banksiae on Banksia formosa, Disculoides corymbiae on Corymbia calophylla, Elsinoë eelemani on Melaleuca alternifolia, Elsinoë eucalyptigena on Eucalyptus kingsmillii, Elsinoë preissianae on Eucalyptus preissiana, Eucasphaeria rustici on Eucalyptus creta, Hyweljonesia queenslandica (incl. Hyweljonesia gen. nov.) on the cocoon of an unidentified microlepidoptera, Mycodiella eucalypti (incl. Mycodiella gen. nov.) on Eucalyptus diversicolor, Myrtapenidiella sporadicae on Eucalyptus sporadica, Neocrinula xanthorrhoeae (incl. Neocrinula gen. nov.) on Xanthorrhoea sp., Ophiocordyceps nooreniae on dead ant, Phaeosphaeriopsis agavacearum on Agave sp., Phlogicylindrium mokarei on Eucalyptus sp., Phyllosticta acaciigena on Acacia suaveolens, Pleurophoma acaciae on Acacia glaucoptera, Pyrenochaeta hakeae on Hakea sp., Readeriella lehmannii on Eucalyptus lehmannii, Saccharata banksiae on Banksia grandis, Saccharata daviesiae on Daviesia pachyphylla, Saccharata eucalyptorum on Eucalyptus bigalerita, Saccharata hakeae on Hakea baxteri, Saccharata hakeicola on Hakea victoria, Saccharata lambertiae on Lambertia ericifolia, Saccharata petrophiles on Petrophile sp., Saccharata petrophilicola on Petrophile fastigiata, Sphaerellopsis hakeae on Hakea sp., and Teichospora kingiae on Kingia australis. Brazil: Adautomilanezia caesalpiniae (incl. Adautomilanezia gen. nov.) on Caesalpina echinata, Arthrophiala arthrospora (incl. Arthrophiala gen. nov.) on Sagittaria montevidensis, Diaporthe caatingaensis (endophyte from Tacinga inamoena), Geastrum ishikawae on sandy soil, Geastrum pusillipilosum on soil, Gymnopus pygmaeus on dead leaves and sticks, Inonotus hymenonitens on decayed angiosperm trunk, Pyricularia urashimae on Urochloa brizantha, and Synnemellisia aurantia on Passiflora edulis. Chile: Tubulicrinis australis on Lophosoria quadripinnata. France: Cercophora squamulosa from submerged wood, and Scedosporium cereisporum from fluids of a wastewater treatment plant. Hawaii: Beltraniella acaciae, Dactylaria acaciae, Rhexodenticula acaciae, Rubikia evansii and Torula acaciae (all on Acacia koa). India: Lepidoderma echinosporum on dead semi-woody stems, and Rhodocybe rubrobrunnea from soil. Iran: Talaromyces kabodanensis from hypersaline soil. La Réunion: Neocordana musarum from leaves of Musa sp. Malaysia: Anungitea eucalyptigena on Eucalyptus grandis × pellita, Camptomeriphila leucaenae (incl. Camptomeriphila gen. nov.) on Leucaena leucocephala, Castanediella communis on Eucalyptus pellita, Eucalyptostroma eucalypti (incl. Eucalyptostroma gen. nov.) on Eucalyptus pellita, Melanconiella syzygii on Syzygium sp., Mycophilomyces periconiae (incl. Mycophilomyces gen. nov.) as hyperparasite on Periconia on leaves of Albizia falcataria, Synnemadiella eucalypti (incl. Synnemadiella gen. nov.) on Eucalyptus pellita, and Teichospora nephelii on Nephelium lappaceum. Mexico: Aspergillus bicephalus from soil. New Zealand: Aplosporella sophorae on Sophora microphylla, Libertasomyces platani on Platanus sp., Neothyronectria sophorae (incl. Neothyronectria gen. nov.) on Sophora microphylla, Parastagonospora phoenicicola on Phoenix canariensis, Phaeoacremonium pseudopanacis on Pseudopanax crassifolius, Phlyctema phoenicis on Phoenix canariensis, and Pseudoascochyta novae-zelandiae on Cordyline australis. Panama: Chalara panamensis from needle litter of Pinus cf. caribaea. South Africa: Exophiala eucalypti on leaves of Eucalyptus sp., Fantasmomyces hyalinus (incl. Fantasmomyces gen. nov.) on Acacia exuvialis, Paracladophialophora carceris (incl. Paracladophialophora gen. nov.) on Aloe sp., and Umthunziomyces hagahagensis (incl. Umthunziomyces gen. nov.) on Mimusops caffra. Spain: Clavaria griseobrunnea on bare ground in Pteridium aquilinum field, Cyathus ibericus on small fallen branches of Pinus halepensis, Gyroporus pseudolacteus in humus of Pinus pinaster, and Pseudoascochyta pratensis (incl. Pseudoascochyta gen. nov.) from soil. Thailand: Neoascochyta adenii on Adenium obesum, and Ochroconis capsici on Capsicum annuum. UK: Fusicolla melogrammae from dead stromata of Melogramma campylosporum on bark of Carpinus betulus. Uruguay: Myrmecridium pulvericola from house dust. USA: Neoscolecobasidium agapanthi (incl. Neoscolecobasidium gen. nov.) on Agapanthus sp., Polyscytalum purgamentum on leaf litter, Pseudopithomyces diversisporus from human toenail, Saksenaea trapezispora from knee wound of a soldier, and Sirococcus quercus from Quercus sp. Morphological and culture characteristics along with DNA barcodes are provided.
- Published
- 2016
39. Investigation of the nuclear matter distribution of Ni-56 by elastic proton scattering in inverse kinematics
- Author
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Sergey Litvinov, D. Nagae, P. J. Woods, Tomohiro Uesaka, M. Thürauf, Takayuki Yamaguchi, C. Nociforo, T. Kröll, B. Streicher, M. Steck, F. Nolden, V. K. Eremin, M. von Schmid, Roman Gernhäuser, A. Krasznahorkay, Nasser Kalantar-Nayestanaki, A.-L. Hartig, M. A. Najafi, Yu. A. Litvinov, H. Kollmus, K. Yue, L. Stuhl, C. Dimopoulou, Hans Geissel, J. Zenihiro, Tatsuya Furuno, S. Ilieva, S. Bönig, C. Scheidenberger, U. Popp, I. Dillmann, Danyal Winters, J. S. Winfield, Manfred Mutterer, Catherine Rigollet, Helmut Weick, O. Kiselev, Santosh Roy, M. Csatlós, J. C. Zamora, M. Mahjour-Shafiei, C. Kozhuharov, Mohsen Harakeh, S. Bagchi, Peter Egelhof, M. Kuilman, Research unit Nuclear & Hadron Physics, and Physics of Nanodevices
- Subjects
Physics ,Nuclear reaction ,Luminosity (scattering theory) ,radioactive beams ,Ni-56 ,Scattering ,ION STORAGE ,Radius ,Inelastic scattering ,direct reactions ,Condensed Matter Physics ,Nuclear matter ,Atomic and Molecular Physics, and Optics ,in-ring experiments ,Nuclear physics ,elastic proton scattering ,GSI ,Excited state ,Atomic physics ,STORAGE-RING ,Nuclear Experiment ,Glauber ,Mathematical Physics ,nuclear-matter distribution ,ESR - Abstract
We have measured the nuclear-matter distribution of the doubly-magic N = Z nucleus Ni-56 by investigating elastic proton scattering in inverse kinematics. The radioactive beam of Ni-56 was injected and stored in the experimental storage ring (ESR, GSI) and interacted with an internal hydrogen gas-jet target. The high revolution frequency of the ions in the ring enabled a high luminosity, despite the low density of the target being used. This way, measurements at very low momentum transfers became possible. By measuring the energy and the scattering angle of the recoiling protons, we were able to separate the elastic reaction channel from inelastic scattering to the first excited 2(+) state of Ni-56 and deduced the differential cross section of Ni-56 (p, p)(56) Ni. The data were analyzed within the framework of the Glauber multiple-scattering theory in order to extract the nuclear-matter radius and radial matter distribution of Ni-56. Parameterizing the matter distribution with the phenomenological Symmetrized Fermi distribution, a preliminary value of 3.5 fm for the rms matter radius was deduced. This experiment was part of an EXL (EXotic nuclei studied in Light-ion induced reactions at storage rings) campaign at GSI in 2012 and was the first successful investigation of nuclear reactions with a stored radioactive beam ever.
- Published
- 2015
40. Isoscalar giant resonance studies in a stored-beam experiment within EXL
- Author
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I. Dillmann, F. Nolden, K. Kollmus, C. Kozhuharov, T. Kröll, Danyal Winters, Peter Egelhof, M. Kuilman, D. Nagae, B. Streicher, P. J. Woods, M. A. Najafi, Takayuki Yamaguchi, Roman Gernhäuser, Sergey Litvinov, M. Steck, Catherine Rigollet, S. Bönig, C. Scheidenberger, V. K. Eremin, M. Mahjour-Shafiei, L. Stuhl, A. Krasznahorkay, Tomohiro Uesaka, Mohsen Harakeh, Santosh Roy, C. Nociforo, O. Kiselev, S. Bagchi, S. Ilieva, J. C. Zamora, Juzo Zenihiro, C. Dimopoulou, U. Popp, Nasser Kalantar-Nayestanaki, A.-L. Hartig, Manfred Mutterer, Yu. A. Litvinov, M. Thürauf, K. Yue, J. S. Winfield, Tatsuya Furuno, H. Geissel, M. Csatlós, Helmut Weick, M. von Schmid, Research unit Nuclear & Hadron Physics, and Physics of Nanodevices
- Subjects
Physics ,NUCLEI ,Isoscalar ,Resonance ,inverse kinematics ,storage ring ,Condensed Matter Physics ,Nuclear matter ,Atomic and Molecular Physics, and Optics ,Nuclear physics ,giant resonance ,Recoil ,Giant resonance ,Atomic physics ,Nuclear Experiment ,Mathematical Physics ,Excitation ,Beam (structure) ,Storage ring - Abstract
In the first campaign of the exotic nuclei studied with light-ion induced reaction in storage rings (EXL) collaboration at the existing storage ring experimental heavy-ion storage ring (ESR) at Helmholtz Center for Heavy Ion Research (GSI), we performed the first experiments using a stored beam of 58Ni and an internal helium gas-jet target aiming for the investigation of isoscalar giant resonances in inverse kinematics. In this experiment, inelastically scattered recoil particles (at very forward angles, °) were detected with a dedicated setup, including ultra-high vacuum (UHV)-compatible double-sided silicon strip detector (DSSDs). Preliminary results show evidence for the excitation of the isoscalar giant monopole resonance (ISGMR) in the 58Ni nucleus. This opens the opportunity to study in the near future giant resonances also with stored radioactive beams, like 56Ni, and extract important information about the nuclear matter incompressibility. In the present work the current status of the data analysis and results are shown and discussed.
- Published
- 2015
41. Fungal Planet 373 – 4 December 2015
- Author
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P W, Crous, M J, Wingfield, J J, Le Roux, D M, Richardson, D, Strasberg, R G, Shivas, P, Alvarado, J, Edwards, G, Moreno, R, Sharma, M S, Sonawane, Y P, Tan, A, Altés, T, Barasubiye, C W, Barnes, R A, Blanchette, D, Boertmann, A, Bogo, J R, Carlavilla, R, Cheewangkoon, R, Daniel, Z W, de Beer, M, de Jesús Yáñez-Morales, T A, Duong, J, Fernández-Vicente, A D W, Geering, D I, Guest, B W, Held, M, Heykoop, V, Hubka, A M, Ismail, S C, Kajale, W, Khemmuk, M, Kolařík, R, Kurli, R, Lebeuf, C A, Lévesque, L, Lombard, D, Magista, J L, Manjón, S, Marincowitz, J M, Mohedano, A, Nováková, N H, Oberlies, E C, Otto, N D, Paguigan, I G, Pascoe, J L, Pérez-Butrón, G, Perrone, P, Rahi, H A, Raja, T, Rintoul, R M V, Sanhueza, K, Scarlett, Y S, Shouche, L A, Shuttleworth, P W J, Taylor, R G, Thorn, L L, Vawdrey, R, Solano-Vidal, A, Voitk, P T W, Wong, A R, Wood, J C, Zamora, and J Z, Groenewald
- Subjects
LSU ,Fungal Planet description sheets ,novel fungal species ,ITS DNA barcodes ,systematics ,Research Article - Abstract
Novel species of fungi described in the present study include the following from Australia: Neoseptorioides eucalypti gen. & sp. nov. from Eucalyptus radiata leaves, Phytophthora gondwanensis from soil, Diaporthe tulliensis from rotted stem ends of Theobroma cacao fruit, Diaporthe vawdreyi from fruit rot of Psidium guajava, Magnaporthiopsis agrostidis from rotted roots of Agrostis stolonifera and Semifissispora natalis from Eucalyptus leaf litter. Furthermore, Neopestalotiopsis egyptiaca is described from Mangifera indica leaves (Egypt), Roussoella mexicana from Coffea arabica leaves (Mexico), Calonectria monticola from soil (Thailand), Hygrocybe jackmanii from littoral sand dunes (Canada), Lindgomyces madisonensis from submerged decorticated wood (USA), Neofabraea brasiliensis from Malus domestica (Brazil), Geastrum diosiae from litter (Argentina), Ganoderma wiiroense on angiosperms (Ghana), Arthrinium gutiae from the gut of a grasshopper (India), Pyrenochaeta telephoni from the screen of a mobile phone (India) and Xenoleptographium phialoconidium gen. & sp. nov. on exposed xylem tissues of Gmelina arborea (Indonesia). Several novelties are introduced from Spain, namely Psathyrella complutensis on loamy soil, Chlorophyllum lusitanicum on nitrified grasslands (incl. Chlorophyllum arizonicum comb. nov.), Aspergillus citocrescens from cave sediment and Lotinia verna gen. & sp. nov. from muddy soil. Novel foliicolous taxa from South Africa include Phyllosticta carissicola from Carissa macrocarpa, Pseudopyricularia hagahagae from Cyperaceae and Zeloasperisporium searsiae from Searsia chirindensis. Furthermore, Neophaeococcomyces is introduced as a novel genus, with two new combinations, N. aloes and N. catenatus. Several foliicolous novelties are recorded from La Réunion, France, namely Ochroconis pandanicola from Pandanus utilis, Neosulcatispora agaves gen. & sp. nov. from Agave vera-cruz, Pilidium eucalyptorum from Eucalyptus robusta, Strelitziana syzygii from Syzygium jambos (incl. Strelitzianaceae fam. nov.) and Pseudobeltrania ocoteae from Ocotea obtusata (Beltraniaceae emend.). Morphological and culture characteristics along with ITS DNA barcodes are provided for all taxa.
- Published
- 2015
42. Recent results on reactions with radioactive beams at RIBRAS (Radioactive Ion Beams in Brazil)
- Author
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Rubens Lichtenthäler, Leandro Gasques, Leistenschneider, Viviane Morcelle, Valdir Brunetti Scarduelli, M. Rodríguez-Gallardo, Valdir Guimaraes, Alinka Lepine-Szily, A. Arazi, D. R. Mendes, Pierre Descouvemont, A. M. Moro, J. C. Zamora, Julian Marco Barbosa Shorto, E. A. Benjamim, M. C. Morais, Adriana Barioni, P. N. de Faria, K. C. C. Pires, and R. Pampa Condori
- Subjects
Nuclear reaction ,Elastic scattering ,History ,Scattering ,Chemistry ,Solenoid ,Isotopes of boron ,Inelastic scattering ,Physique atomique et nucléaire ,Computer Science Applications ,Education ,Nuclear physics ,Pelletron ,Physics::Accelerator Physics ,Atomic physics ,Nuclear Experiment ,Isotopes of helium - Abstract
We present a quick description of RIBRAS (Radioactive Ion beams in Brazil), which is a superconducting double solenoid system, installed at the Pelletron Laboratory of the University of São Paulo and extends the capabilities of the original Pelletron Tandem Accelerator of 8MV terminal voltage (8UD) by producing secondary beams of unstable nuclei. The experimental program of the RIBRAS covers the study of elastic and inelastic scattering with the objective to study the interaction potential and the reaction mechanisms between weakly bound (RIB) and halo (6He and 8B) projectiles on light, medium and heavy mass targets. With highly purified beams, the study of resonant elastic scattering and resonant transfer reactions, using inverse kinematics and thick targets, have also been included in our recent experimental program., SCOPUS: cp.j, info:eu-repo/semantics/published
- Published
- 2015
43. Nuclear reactions in the storage ring ESR with EXL
- Author
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B. Streicher, Yu. A. Litvinov, L. Stuhl, Tatsuya Furuno, P. J. Woods, M. Steck, Danyal Winters, C. Dimopoulou, C. Scheidenberger, Roman Gernhäuser, V. K. Eremin, Takayuki Yamaguchi, F. Nolden, S. Bönig, M. Csatlós, M. Thürauf, Catherine Rigollet, Nasser Kalantar-Nayestanaki, A. Krasznahorkay, J. C. Zamora, D. Nagae, A.-L. Hartig, I. Dillmann, S. Ilieva, Tomohiro Uesaka, Helmut Weick, M. Mahjour-Shafiei, Hans Geissel, C. Nociforo, Sergey Litvinov, Mohsen Harakeh, S. Bagchi, Peter Egelhof, M. Kuilman, H. Kollmus, Manfred Mutterer, M. A. Najafi, Th. Kröll, Sourov Roy, M. von Schmid, K Yue, C. Kozhuharov, U. Popp, J. S. Winfield, O. Kiselev, and Juzo Zenihiro
- Subjects
Physics ,Nuclear reaction ,History ,010308 nuclear & particles physics ,Nuclear structure ,01 natural sciences ,Computer Science Applications ,Education ,Nuclear physics ,0103 physical sciences ,ddc:530 ,010306 general physics ,Radioactive beam ,Storage ring - Abstract
21st International School on Nuclear Physics and Applications & the International Symposium on Exotic Nuclei, Varna, Bulgaria, 7 Sep 2015 - 12 Sep 2015; Journal of physics / Conference Series Conference Series 724(1), 012026 - (2016). doi:10.1088/1742-6596/724/1/012026, The EXL project aims to study nuclear structure by direct reactions in inverse kinematics at the storage rings of the future FAIR facility. In this contribution, we present the status of the project: the technical implementation at the ESR at GSI and preliminary results of the EXL campaign in 2012, the first using also a radioactive beam., Published by IOP Publ., Bristol
- Published
- 2016
44. Nuclear transfer reaction measurements at the ESR—for the investigation of the astrophysical15O(α,γ)19Ne reaction
- Author
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D. T. Doherty, Manfred Mutterer, J. C. Zamora, F. Nolden, P. J. Woods, S. Bagchi, M. Steck, A. Evdokimov, Yu. A. Litvinov, C. Lederer, O. Kiselev, C. Brandau, T. Davinson, Sergiy Trotsenko, A. Gumberidze, Shawn Bishop, C. Kozhuharov, Th. Stöhlker, Matthias Heil, M. Ali Najafi, U. Popp, Gavin Lotay, M. Bo, Santosh Roy, X. L. Yan, Nasser Kalantar-Nayestanaki, B. Streicher, Catherine Rigollet, Sergey Litvinov, I. Dillmann, Rene Reifarth, T. Kröll, N. Petridis, M. Mahjour-Shafei, M. von Schmid, Peter Egelhof, and A. Estrade
- Subjects
Physics ,Nuclear reaction ,CNO cycle ,Astrophysics::High Energy Astrophysical Phenomena ,Cosmic ray ,Astrophysics ,Condensed Matter Physics ,Atomic and Molecular Physics, and Optics ,Luminosity ,Nuclear physics ,Neutron star ,Deuterium ,Nuclear astrophysics ,Astrophysics::Solar and Stellar Astrophysics ,r-process ,Mathematical Physics - Abstract
Astrophysical x-ray bursts are thought to be a result of thermonuclear explosions on the atmosphere of an accreting neutron star. Between these bursts, energy is thought to be generated by the hot CNO cycles. The O-15(alpha,gamma)Ne-19 reaction is one reaction that allows breakout from these CNO cycles and into the rp-process to fuel outbursts. The reaction is expected to be dominated by a single 3/2(+) resonance at 4.033 MeV in Ne-19, however, limited information is available on this key state. This work reports on a pioneering study of the Ne-20(p, d)Ne-19 reaction, performed in inverse kinematics at the experimental storage ring (ESR) as a means of accessing the astrophysically important 4.033 MeV state in Ne-19. The unique, background free, high luminosity conditions of the storage ring were utilized for this, the first transfer reaction performed at the ESR. The results of this pioneering test experiment are presented along with suggestions for future measurements at storage ring facilities.
- Published
- 2015
45. Experimental techniques for in-ring reaction experiments
- Author
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V. K. Eremin, H. Kollmus, Manfred Mutterer, T. Kröll, B. Streicher, Nasser Kalantar-Nayestanaki, M. A. Najafi, P. Egelhof, Catherine Rigollet, M. von Schmid, L.X. Chung, Santosh Roy, J. C. Zamora, U. Popp, M. Kuilman, M. Träger, O.A. Kiselev, S Ilieva, K. Yue, Research unit Nuclear & Hadron Physics, and Physics of Nanodevices
- Subjects
Physics ,Nuclear reaction ,Elastic scattering ,radioactive beams ,Ni-56 ,Ni-58 ,Detector ,UHV technology ,Condensed Matter Physics ,Ring (chemistry) ,in-ring experiments ,Atomic and Molecular Physics, and Optics ,elastic proton scattering ,Nuclear physics ,Recoil ,differential pumping ,Ni-56,Ni-58 ,Nuclear Experiment ,Mathematical Physics ,Storage ring - Abstract
As a first step of the EXL project scheduled for the New Experimental Storage Ring at FAIR a precursor experiment (E105) was performed at the ESR at GSI. For this experiment, an innovative differential pumping concept, originally proposed for the EXL recoil detector ESPA, was successfully applied. The implementation and essential features of this novel technical concept will be discussed, as well as details on the detectors and the infrastructure around the internal gas-jet target. With Ni-56(p, p)Ni-56 elastic scattering at 400 MeV u(-1), a nuclear reaction experiment with stored radioactive beams was realized for the first time. Finally, perspectives for a next-generation EXL-type setup are briefly discussed.
- Published
- 2015
46. Nuclear reactions in the storage ring ESR with EXL.
- Author
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Th Kröll, M von Schmid, J C Zamora, S Bagchi, S Bönig, M Csatlós, I Dillmann, C Dimopoulou, P Egelhof, V Eremin, T Furuno, H Geissel, R Gernhäuser, M N Harakeh, A L Hartig, S Ilieva, N Kalantar-Nayestanaki, O Kiselev, H Kollmus, and C Kozhuharov
- Published
- 2016
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