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2. Long term measurements of aerosol optical properties at a pristine forest site in Amazonia

Author

L. V. Rizzo, P. Artaxo, T. Müller, A. Wiedensohler, M. Paixão, G. G. Cirino, A. Arana, E. Swietlicki, P. Roldin, E. O. Fors, K. T. Wiedemann, L. S. M. Leal, and M. Kulmala

Subjects
complex mixtures
Abstract

A long term experiment was conducted in a pristine area in the Amazon forest, with continuous in situ measurements of aerosol optical properties between February 2008 and April 2011, comprising, to our knowledge, the longest database ever in Amazonia. Two types of aerosol particles, with significantly different optical properties were identified: coarse mode predominant biogenic aerosols in the wet season (January–June), naturally released by the forest metabolism, and fine mode dominated biomass burning aerosols in the dry season (July–December), transported from regional fires. Dry particle median scattering coefficients at the wavelength of 550 nm increased from 6.3 Mm−1 to 22 Mm−1, whereas absorption at 637 nm increased from 0.5 Mm−1 to 2.8 Mm−1 from wet to dry season. Most of the scattering in the dry season was attributed to the predominance of fine mode particles (40–80% of PM10 mass), while the enhanced absorption coefficients are attributed to the presence of light absorbing aerosols from biomass burning. As both scattering and absorption increased in the dry season, the single scattering albedo (SSA) did not show a significant seasonal variability, in average 0.86 ± 0.08 at 637 nm for dry particles. Measured particle optical properties were used to estimate the aerosol forcing efficiency at the top of the atmosphere. Results indicate that in this pristine forest site the radiative balance was dominated by the cloud cover, or, in other words, the aerosol indirect effect predominated over the direct effect, particularly in the wet season. Due to the high cloud fractions, the aerosol forcing efficiency was below −3.5 W m−2 in 70% of the wet season days and in 46% of the dry season days. These values are lower than the ones reported in the literature, which are based on remote sensing data. Besides the seasonal variation, the influence of external aerosol sources was observed occasionally. Periods of influence of the Manaus urban plume were detected, characterized by a consistent increase on particle scattering (factor 2.5) and absorption coefficients (factor 5). Episodes of biomass burning and mineral dust particles advection from Africa were observed between January and April, characterized by enhanced concentrations of fine mode (PM2.0), crustal elements (Al, Si, Ti, Fe) and potassium. During these episodes, median particle absorption coefficients increased by a factor of 2, whereas median SSA values decreased by 7%, in comparison to wet season conditions.

Published
2012
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3. Coherent contributions to isospin mixing in the mirror pair 67As and 67Se

Author

R, Orlandi, G, de Angelis, P G, Bizzeti, S, Lunardi, A, Gadea, A M, Bizzeti-Sona, A, Bracco, F, Brandolini, M P, Carpenter, C J, Chiara, F, Della Vedova, E, Farnea, J P, Greene, S M, Lenzi, S, Leoni, C J, Lister, N, Mărginean, D, Mengoni, D R, Napoli, B S Nara, Singh, O L, Pechenaya, F, Recchia, W, Reviol, E, Sahin, D G, Sarantites, D, Seweryniak, D, Tonev, C A, Ur, J J, Valiente-Dobón, R, Wadsworth, K T, Wiedemann, and S, Zhu

Abstract

Isospin symmetry breaking has been investigated in mass A=67 mirror nuclei through the experimental determination of the E1 strengths of analog electromagnetic transitions. Lifetimes of excited states have been measured in (67)Se and (67)As with the centroid shift method. Through the comparison of the B(E1) strengths of the mirror 9/2(+)--7/2(-) transitions, the isovector and the isoscalar components of the electromagnetic transition amplitude were extracted. The presence of a large isoscalar component provides evidence for coherent contributions to isospin mixing, probably involving the isovector giant monopole resonance.

Published
2009

4. Stopping Power of Au for Ti Using Elastic Recoil Technique

Author

R. Linares, J. A. Freire, R. V. Ribas, N. H. Medina, J. R. B. Oliveira, W. A. Seale, E. W. Cybulska, K. T. Wiedemann, P. R. Allegro, D. L. Toufen, Valdir Guimaraes, José R. B. Oliveira, Kita C. D. Macario, and Frederico A. Genezini

Subjects
Nuclear physics, Elastic recoil, Physics, Elastic scattering, Recoil, Theoretical models, Atomic physics, Stopping power, Nuclear Experiment, Beam (structure), Ion
Abstract

The slowing down of heavy ions in matter is still not well understood especially at low energies (

Published
2009
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5. [sup 67]As-[sup 67]Se mirror pair spectroscopy

Author

K. T. Wiedemann, N. H. Medina, G. de Angelis, R. Orlandi, A. Bracco, M. Carpenter, C. J. Chiara, F. Della Vedova, E. Farnea, A. Gadea, J. Greene, S. M. Lenzi, S. Leoni, C. J. Lister, S. Lunardi, N. Mărginean, D. R. Napoli, B. S. Nara Singh, O. L. Pechenaya, W. Reviol, E. Sahin, D. G. Sarantites, D. Seweryniak, D. Tonev, C. A. Ur, J. J. Valiente-Dobón, R. Wadsworth, S. Zhu, Valdir Guimaraes, José R. B. Oliveira, Kita C. D. Macario, and Frederico A. Genezini

Subjects
Physics, Fusion, Nuclear Theory, Nuclear structure, Parity (physics), Nuclear physics, Physics::Accelerator Physics, Neutron, Gammasphere, Gamma spectroscopy, Mirror nuclei, Atomic physics, Nuclear Experiment, Spectroscopy
Abstract

This work focus on the electromagnetic decay properties of the heaviest known mirror pair 67As and 67Se, produced in the fusion evaporation reaction 32S+40Ca, with a E = 90 MeV beam provided by the ATLAS accelerator at Argonne National Laboratory. The high selectivity required to investigate these proton‐rich nuclei was achieved with the concurrent employment of Gammasphere, Neutron‐Shell, and Microball. The full array allowed to obtain the level scheme of the 67Se nucleus up to 5.56 MeV, and 5 new transitions were assigned to the known 67As level‐scheme. The level spin and parities were assigned using the ADO analysis and symmetry arguments.

Published
2009
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6. Nuclear structure far from stability at the N=50 shell closure

Author

E. Sahin, G. de Angelis, A. Gadea, G. Duchene, T. Faul, D. R. Napoli, E. Farnea, J. J. Valiente-Dobón, R. Orlandi, D. Mengoni, F. Della Vedova, R. P. Singh, C. Ur, F. Recchia, M. N. Erduran, M. Bostan, S. Erturk, S. Aydin, K. T. Wiedemann, A. M. Stefanini, S. Lenzi, S. Lunardi, N. Marginean, L. Corradi, E. Fioretto, G. Montagnoli, F. Scarlassara, P. Mason, S. Szilner, D. Ackermann, G. Pollarolo, J. R. B. Oliveira, T. Byrski, D. Curien, B. Gall, F. Haas, O. Dorwaux, J. Robin, M. Nespolo, F. Azaiez, G. De France, A. Algora, X. Liang, F. Nowacki, Y. H. Zhang, X. H. Zhou, P. Demetriou, R. Julin, S. V. Harissopulos, Institut Pluridisciplinaire Hubert Curien (IPHC), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire d'Orsay (IPNO), 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), Grand Accélérateur National d'Ions Lourds (GANIL), 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), Université de Strasbourg (UNISTRA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), 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), 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), Sahin, E., Department of Physics, Istanbul University, Istanbul, 34134, Turkey, INFN, Laboratori Nazionali di Legnaro, Italy -- De Angelis, G., INFN, Laboratori Nazionali di Legnaro, Italy -- Gadea, A., INFN, Laboratori Nazionali di Legnaro, Italy -- Duchene, G., IPHC, IN2P3/CNRS et Univesitè Louis Pasteur, BP 28, Strasburg-Cedex-2, F-67037, France -- Faul, T., IPHC, IN2P3/CNRS et Univesitè Louis Pasteur, BP 28, Strasburg-Cedex-2, F-67037, France -- Napoli, D.R., INFN, Laboratori Nazionali di Legnaro, Italy -- Farnea, E., Dipartimento di Fisica, Universitá di Padova and INFN, Sezione di Padova, Padova, Italy -- Valiente-Dobón, J.J., INFN, Laboratori Nazionali di Legnaro, Italy -- Orlandi, R., INFN, Laboratori Nazionali di Legnaro, Italy -- Mengoni, D., Dipartimento di Fisica, Universitá di Padova and INFN, Sezione di Padova, Padova, Italy -- Vedova, F.D., INFN, Laboratori Nazionali di Legnaro, Italy -- Singh, R.P., Inter-University Accelerator Center, New Delhi-67, India -- Ur, C., Dipartimento di Fisica, Universitá di Padova and INFN, Sezione di Padova, Padova, Italy -- Recchia, F., INFN, Laboratori Nazionali di Legnaro, Italy -- Erduran, M.N., Department of Physics, Istanbul University, Istanbul, 34134, Turkey -- Bostan, M., Department of Physics, Istanbul University, Istanbul, 34134, Turkey -- Erturk, S., Department of Physics, Nigde University, Nigde, Turkey -- Aydin, S., Department of Physics, Cukurova University, Adana, Turkey -- Wiedemann, K.T., University of São Paulo, Sãu Paulo, Brazil -- Stefanini, A.M., INFN, Laboratori Nazionali di Legnaro, Italy -- Lenzi, S., Dipartimento di Fisica, Universitá di Padova and INFN, Sezione di Padova, Padova, Italy -- Lunardi, S., Dipartimento di Fisica, Universitá di Padova and INFN, Sezione di Padova, Padova, Italy -- Marginean, N., INFN, Laboratori Nazionali di Legnaro, Italy -- Corradi, L., INFN, Laboratori Nazionali di Legnaro, Italy -- Fioretto, E., INFN, Laboratori Nazionali di Legnaro, Italy -- Montagnoli, G., Dipartimento di Fisica, Universitá di Padova and INFN, Sezione di Padova, Padova, Italy -- Scarlassara, F., Dipartimento di Fisica, Universitá di Padova and INFN, Sezione di Padova, Padova, Italy -- Mason, P., Dipartimento di Fisica, Universitá di Padova and INFN, Sezione di Padova, Padova, Italy -- Szilner, S., Ruder Boskovic Institute, Zagreb Crotia, HR-1002, Croatia -- Ackermann, D., Kernphysik II, Gesellschaft für Schwerionenforschung MbH A GSI, Planckstr.1, Darmstadt, D-64291, Germany -- Pollarolo, G., Dipartimento di Fisica Teorica, Universitá di Torino and INFN, Sezione di Torino, Italy -- Oliveira, J.R.B., University of São Paulo, Sãu Paulo, Brazil -- Byrski, T., IPHC, IN2P3/CNRS et Univesitè Louis Pasteur, BP 28, Strasburg-Cedex-2, F-67037, France -- Curien, D., IPHC, IN2P3/CNRS et Univesitè Louis Pasteur, BP 28, Strasburg-Cedex-2, F-67037, France -- Gall, B., IPHC, IN2P3/CNRS et Univesitè Louis Pasteur, BP 28, Strasburg-Cedex-2, F-67037, France -- Haas, F., IPHC, IN2P3/CNRS et Univesitè Louis Pasteur, BP 28, Strasburg-Cedex-2, F-67037, France -- Dorwaux, O., IPHC, IN2P3/CNRS et Univesitè Louis Pasteur, BP 28, Strasburg-Cedex-2, F-67037, France -- Robin, J., IPHC, IN2P3/CNRS et Univesitè Louis Pasteur, BP 28, Strasburg-Cedex-2, F-67037, France -- Nespolo, M., Dipartimento di Fisica, Universitá di Padova and INFN, Sezione di Padova, Padova, Italy -- Azaiez, F., IPNO, IN2P3/CNRS et Universit Paris-Sud, Orsay, F-91406, France -- De France, G., GANIL Caen 2c013, France -- Algora, A., Institute of Nuclear Research, Debrecen, Pf. 51, H-4001, Hungary -- Liang, X., Electronic Engineering and Physics, University of Paisley, Paisley, PA1 2BE, United Kingdom -- Nowacki, F., IPHC, IN2P3/CNRS et Univesitè Louis Pasteur, BP 28, Strasburg-Cedex-2, F-67037, France -- Zhang, Y.H., Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, China -- Zhou, X.H., Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, China, Demetriou, P., Julin, R., Harissopulos, S.V., Çukurova Üniversitesi, Demetriuo, P, Harissopulos, SV, Napoli, Daniel Ricardo -- 0000-0002-8154-6958, Algora, Alejandro -- 0000-0002-5199-1794, Gadea, Andres -- 0000-0002-4233-1970, Oliveira, Jose Roberto -- 0000-0003-1362-7382, de France, Gilles -- 0000-0002-7439-1759, Montagnoli, Giovanna -- 0000-0002-8944-1456, Ackermann, Dieter -- 0000-0001-6284-1516, Sahin, Eda -- 0000-0003-0683-5140, [Sahin, E. -- Erduran, M. N. -- Bostan, M.] Istanbul Univ, Dept Phys, TR-34134 Istanbul, Turkey -- [Sahin, E. -- de Angelis, G. -- Gadea, A. -- Napoli, D. R. -- Valiente-Dobon, J. J. -- Orlandi, R. -- Della Vedova, F. -- Recchia, F. -- Stefanini, A. M. -- Marginean, N. -- Corradi, L. -- Fioretto, E.] Ist Nazl Fis Nucl, Lab Nazl Legnaro, Legnaro, Italy -- [Duchene, G. -- Faul, T. -- Byrski, T. -- Curien, D. -- Gall, B. -- Haas, F. -- Dorwaux, O. -- Robin, J. -- Nowacki, F.] Univ Louis Pasteur, IPHC, IN2P3, CNRS, F-67037 Strasbourg 2, France -- [Farnea, E. -- Mengoni, D. -- Ur, C. -- Lenzi, S. -- Lunardi, S. -- Montagnoli, G. -- Scarlassara, E. -- Mason, P. -- Nespolo, M.] Univ Padua, Dipartimento Fis, Padua, Italy -- [Farnea, E. -- Mengoni, D. -- Ur, C. -- Lenzi, S. -- Lunardi, S. -- Montagnoli, G. -- Scarlassara, E. -- Mason, P. -- Nespolo, M.] Ist Nazl Fis Nucl, Sezione Padova, Padua, Italy -- [Singh, R. P.] Inter Univ Accelerator Ctr, New Delhi 67, India -- [Erturk, S.] Nigde Univ, Dept Phys, Nigde, Turkey -- [Aydin, S.] Cukurova Univ, Dept Phys, Adana, Turkey -- [Wiedemann, K. T. -- Oliveira, J. R. B.] Univ Sao Paulo, Sao Paulo, Brazil -- [Szilner, S.] Rudjer Boskovic Inst, Zagreb 1002, Croatia -- [Ackermann, D.] GSI Helmholtzzentrum Schwerionenforsch mbH, Kernphys 2, D-64291 Darmstadt, Germany -- [Pollarolo, G.] Univ Turin, Dipartmento Fis Teor, Turin, Italy -- [Pollarolo, G.] Ist Nazl Fis Nucl, Sezione Torino, Turin, Italy -- [Azaiez, E.] Univ Paris 11, IPNO, IN2P3, CNRS, F-91406 Orsay, France -- [De France, G.] GANIL, F-2013 Caen, France -- [Algora, A.] Inst Nucl Res, H-4001 Debrecen, Hungary -- [Liang, X.] Univ Paisley, Elect Engn & Phys, Paisley PA1 2BE, Renfrew, Scotland -- [Zhang, Y. H. -- Zhou, X. H.] Chinese Acad Sci, Inst Modern Phys, Lanzhou, Peoples R China, and 0-Belirlenecek

Subjects
Spin states, neutron-rich, multi-nucleon transfer, Nuclear Theory, Shell (structure), Closure (topology), [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, 7. Clean energy, Nuclear physics, single-particle state, 0103 physical sciences, 010306 general physics, deep inelastic, Nuclear Experiment, Physics, 010308 nuclear & particles physics, Nuclear structure, Nuclear shell model, Gamma ray, shell model, isotones N=50, muliti-nucleon transfer, shell closure, Deep inelastic scattering, 0-Belirlenecek, Excited state, Atomic physics
Abstract

Conference on Frontiers in Nuclear Structure, Astrophysics, and Reactions -- SEP 10-14, 2007 -- Crete, GREECE, WOS: 000256223700023, Medium and high spin states of the nuclei close to the N=50 shell closure are investigated Using deep inelastic and multi-nucleon transfer reactions. New excited states of the nuclei Ga-81, Ge-82 and As-83 at N=50 shell closure have been identified by means of the Se-82+U-238 reaction. Gamma rays have been acquired using the PRISMA-CLARA setup of the Laboratori Nazionali di Legnaro, Italy (LNL)., NCSR, Univ Jyvaskyla, Natl Tech Univ Athens, Greek Minist Educ, U.S. Department of Energy [DE-AC05-00OR22725], I wish to thank the staff of HRIBF for their dedication in the production of RIBs. This talk is based on work done in collaboration with various individuals: C. Baktash, J. Batchelder, J.R. Beene, B. Fuentes, J. Gomez del Campo, C.J. Gross, M.L. Halbert, P.A. Hausladen, Y. Larochelle, J. F.Liang, P.E. Mueller, E. Padilla-Rodal, D.C. Radford, D. Shapira, D.W. Stracener, J. P. Urrego, R.L. Varner and C.-H. Yu. Oak Ridge National Laboratory is managed by UT-Battelle, LLC for the U.S. Department of Energy under Contract No. DE-AC05-00OR22725.

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7. Adaptation and test of the Saci-Perere spectrometer for nuclear reaction studies

Author

J. R. B. Oliveira, D. Pereira, P. R. P. Allegro, R. Linares, D. L. Toufen, K. T. Wiedemann, W. A. Seale, E. W. Cybulska, N. H. Medina, R. V. Ribas, J. Lubian, Valdir Guimaraes, José R. B. Oliveira, Kita C. D. Macario, and Frederico A. Genezini

Subjects
Nuclear physics, Physics, Nuclear reaction, Spectrometer, Gamma spectroscopy, Neutron
Abstract

In this work we present the results of in beam tests of the adaptations of the Saci‐Perere spectrometer (IFUSP) for nuclear reaction mechanism studies.

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