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2,346 results on '"Petri, M. A."'

2. Climate change impacts on a sedimentary coast—a regional synthesis from genes to ecosystems

Author

Buschbaum, Christian, Shama, L. N. S., Amorim, F. L. L., Brand, S., Broquard, C. M. A., Camillini, N., Cornelius, A., Dolch, T., Dummermuth, A., Feldner, J., Guignard, M. S., Habedank, J., Hoffmann, J. J. L., Horn, S., Konyssova, G., Koop-Jakobsen, K., Lauerburg, R., Mehler, K., Odongo, V., Petri, M., Reents, S., Rick, J. J., Rubinetti, S., Salahi, M., Sander, L., Sidorenko, V., Spence-Jones, H. C., van Beusekom, J. E. E., Waser, A. M., Wegner, K. M., and Wiltshire, K. H.

Published
2024
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3. Evolution of structure and shapes in Er158 to ultrahigh spin

Author

Simpson, J, Riley, MA, Pipidis, A, Paul, ES, Wang, X, Nolan, PJ, Sharpey-Schafer, JF, Aguilar, A, Appelbe, DE, Ayangeakaa, AD, Boston, AJ, Boston, HC, Campbell, DB, Carpenter, MP, Chiara, CJ, Choy, PTW, Clark, RM, Cromaz, M, Evans, AO, Fallon, P, Garg, U, Görgen, A, Hartley, DJ, Janssens, RVF, Joss, DT, Judson, DS, Kondev, FG, Lauritsen, T, Lee, IY, Macchiavelli, AO, Matta, JT, Ollier, J, Petri, M, Revill, JP, Riedinger, LL, Rigby, SV, Teal, C, Twin, PJ, Unsworth, C, Ward, D, Zhu, S, and Ragnarsson, I

Subjects
Nuclear and Plasma Physics, Synchrotrons and Accelerators, Physical Sciences, Nuclear and plasma physics
Abstract

The level structure of Er158 has been studied using the Gammasphere spectrometer via the Cd114(Ca48,4n) reaction at 215 MeV with both thin (self-supporting) and thick (backed) targets. The level scheme has been considerably extended with more than 200 new transitions and six new rotational structures, including two strongly coupled high-K bands. Configuration assignments for the new structures are based on their observed alignments, B(M1)/B(E2) ratios of reduced transition probabilities, excitation energies, and comparisons with neighboring nuclei and theoretical calculations. With increasing angular momentum, this nucleus exhibits Coriolis-induced alignments of both neutrons and protons before it then undergoes a rotation-induced transition from near-prolate collective rotation to a noncollective oblate configuration. This transition occurs via the mechanism of band termination around spin 45ħ in three rotational structures. Two distinct lifetime branches, consistent with the crossing of a collective "fast"rotational structure by an energetically favored "slow"terminating sequence, are confirmed for the positive-parity states, and similar behavior is established in the negative-parity states. Weak-intensity, high-energy transitions are observed to feed into the terminating states. At the highest spins, three collective bands with high dynamic moments of inertia and large quadrupole moments were identified. These bands are interpreted as triaxial strongly deformed structures and mark a return to collectivity at ultrahigh spin.

Published
2023

4. Quasi-free (p,2p) reactions in inverse kinematics for studying the fission yield dependence on temperature

Author

Graña-González, A., Rodríguez-Sánchez, J. L., Benlliure, J., García-Jiménez, G., Alvarez-Pol, H., Cortina-Gil, D., Atar, L., Audouin, L., Authelet, G., Besteiro, A., Blanchon, G., Boretzky, K., Cabanelas, P., Casarejos, E., Cederkall, J., Chatillon, A., Corsi, A., Feijoo, M., Galaviz, D., Gasparic, I., Gernhäuser, R., Heil, M., Heinz, A., Holl, M., Jenegger, T., Ji, L., Johansson, H. T., Kiselev, O. A., Klenze, P., Knyazev, A., Körper, D., Kröll, T., Lihtar, I., Litvinov, Y. A., Löher, B., Morfouace, P., Mücher, D., Murillo-Morales, S., Obertelli, A., Panin, V., Park, J., Paschalis, S., Perea, A., Petri, M., Pirrone, S., Ponnath, L., Revel, A., Rhee, H. B., Rose, L., Rossi, D. M., Russotto, P., Simon, H., Stott, A., Sun, Y., Sürder, C., Taïeb, J., Taniuchi, R., Tengblad, O., Törnqvist, H. T., Velardita, S., Vesic, J., and Voss, B.

Subjects
Nuclear Experiment
Abstract

Despite the recent experimental and theoretical progress in the investigation of the nuclear fission process, a complete description still represents a challenge in nuclear physics because it is a very complex dynamical process, whose description involves the coupling between intrinsic and collective degrees of freedom, as well as different quantum-mechanical phenomena. To improve on the existing data on nuclear fission, we produce fission reactions of heavy nuclei in inverse kinematics by using quasi-free (p,2p) scattering, which induce fission through particle-hole excitations that can range from few to ten's of MeV. The measurement of the four-momenta of the two outgoing protons allows to reconstruct the excitation energy of the fissioning compound nucleus and therefore to study the evolution of the fission yields with temperature. The realization of this kind of experiment requires a complex experimental setup, providing full isotopic identification of both fission fragments and an accurate measurement of the momenta of the two outgoing protons. This was realized recently at the GSI/FAIR facility and here some preliminary results are presented., Comment: 6 pages, 2 figures, FAIRNESS 2022. arXiv admin note: text overlap with arXiv:2210.04741

Published
2022

5. The Core of $^{25}$F studied by the $^{25}$F(-1p)$^{24}$O reaction

Author

Crawford, H. L., Jones, M. D., Macchiavelli, A. O., Fallon, P., Bazin, D., Bender, P. C., Brown, B. A., Campbell, C. M., Clark, R. M., Cromaz, M., Elman, B., Gade, A., Holt, J. D., Janssens, R. V. F., Lee, I. Y., Longfellow, B., Paschalis, S., Petri, M., Richard, A. L., Salathe, M., Tostevin, J. A., and Weisshaar, D.

Subjects
Nuclear Experiment, Nuclear Theory
Abstract

The $^{25}$F($5/2^+) (-1p) ^{24}$O reaction was studied at the NSCL using the S800 spectrometer. The experimental spectroscopic factor for the ground-state to ground-state transition indicates a substantial depletion of the proton $d_{5/2}$ strength compared to shell-model expectations. Our result supports the findings reported by Tang \textit{et al.}, from their study of the $(p,2p)$ reaction at RIBF. The overlap between the $^{25}$F and $^{24}$O ground-states is considerably less than anticipated if $^{24}$O acted as a robust and rigid doubly-magic core in $^{25}$F. We interpret the results within the framework of the Particle-Vibration Coupling (PVC) of a $d_{5/2}$ proton coupled to a quadrupole phonon of an effective core. This approach provides a good description of the experimental data by requiring an effective $^{24}$O* core with a phonon energy of $\hbar\omega_2$= 3.2 MeV, and a $B(E2) ~ 2.7$ W.u., softer and more collective than a bare $^{24}$O. Both the Nilsson deformed mean field and the PVC models appear to capture the properties of the effective core of $^{25}$F, suggesting that the additional proton tends to polarize the free, doubly magic $^{24}$O in such a way that it becomes either slightly deformed or a quadrupole vibrator., Comment: 6 pages, 2 figures

Published
2022

6. A new study of the $N=32$ and $N=34$ shell gap for Ti and V by the first high-precision MRTOF mass measurements at BigRIPS-SLOWRI

Author

Iimura, S., Rosenbusch, M., Takamine, A., Tsunoda, Y., Wada, M., Chen, S., Hou, D. S., Xian, W., Ishiyama, H., Yan, S., Schury, P., Crawford, H., Doornenbal, P., Hirayama, Y., Ito, Y., Kimura, S., Koiwai, T., Kojima, T. M., Koura, H., Lee, J., Liu, J., Michimasa, S., Miyatake, H., Moon, J. Y., Nishimura, S., Naimi, S., Niwase, T., Odahara, A., Otsuka, T., Paschalis, S., Petri, M., Shimizu, N., Sonoda, T., Suzuki, D., Watanabe, Y. X., Wimmer, K., and Wollnik, H.

Subjects
Nuclear Experiment
Abstract

The atomic masses of $^{55}$Sc, $^{56,58}$Ti, and $^{56-59}$V have been determined using the high-precision multi-reflection time-of-flight technique. The radioisotopes have been produced at RIKEN's RIBF facility and delivered to the novel designed gas cell and multi-reflection system (ZD MRTOF), which has been recently commissioned downstream of the ZeroDegree spectrometer following the BigRIPS separator. For $^{56,58}$Ti and $^{56-59}$V the mass uncertainties have been reduced down to the order of $10\,\mathrm{keV}$, shedding new light on the $N=34$ shell effect in Ti and V isotopes by the first high-precision mass measurements of the critical species $^{58}$Ti and $^{59}$V. With the new precision achieved, we reveal the non-existence of the $N=34$ empirical two-neutron shell gaps for Ti and V, and the enhanced energy gap above the occupied $\nu p_{3/2}$ orbit is identified as a feature unique to Ca. We perform new Monte Carlo shell model calculations including the $\nu d_{5/2}$ and $\nu g_{9/2}$ orbits and compare the results with conventional shell model calculations, which exclude the $\nu g_{9/2}$ and the $\nu d_{5/2}$ orbits. The comparison indicates that the shell gap reduction in Ti is related to a partial occupation of the higher orbitals for the outer two valence neutrons at $N=34$.

Published
2022
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7. Core of F25 studied by the F25(−p) proton-removal reaction

Author

Crawford, HL, Jones, MD, Macchiavelli, AO, Fallon, P, Bazin, D, Bender, PC, Brown, BA, Campbell, CM, Clark, RM, Cromaz, M, Elman, B, Gade, A, Holt, JD, Janssens, RVF, Lee, IY, Longfellow, B, Paschalis, S, Petri, M, Richard, AL, Salathe, M, Tostevin, JA, and Weisshaar, D

Subjects
Nuclear and Plasma Physics, Synchrotrons and Accelerators, Physical Sciences, Nuclear and plasma physics
Abstract

The Be9(BeF25(5/2+),BeO24)X proton-removal reaction was studied at the NSCL using the S800 spectrometer. The experimental spectroscopic factor for the ground-state to ground-state transition indicates a substantial depletion of the proton d5/2 strength compared to shell-model expectations, similar to the findings of an inverse-kinematics (p,2p) measurement performed at RIBF. The BeF25 to BeO24 ground-states overlap is considerably less than anticipated if the core nucleons behaved as rigid, doubly-magic BeO24 within BeF25. We interpret the new results within the framework of the Particle-Vibration Coupling (PVC) model, of a d5/2 proton coupled to a quadrupole phonon of an effective core. This approach provides a good description of the experimental data, requiring an effective BeO∗24 core with a phonon energy of ħω2= 3.2 MeV and a B(E2)≈2.7 W.u. - softer and more collective than a bare BeO24. Both the Nilsson deformed mean field and the PVC models appear to capture the properties of the effective core of BeF25, suggesting that the additional proton polarizes BeO24 in such a way that it becomes either slightly deformed or a quadrupole vibrator.

Published
2022

9. Probing the Z = 6 spin-orbit shell gap with (p,2p) quasi-free scattering reactions

Author

Syndikus, I., Petri, M., Macchiavelli, A. O., Paschalis, S., Bertulani, C. A., Aumann, T., Alvarez-Pol, H., Atar, L., Beceiro-Novo, S., Benlliure, J., Boillos, J. M., Boretzky, K., Borge, M. J. G., Brown, B. A., Caamaño, M., Caesar, C., Casarejos, E., Catford, W., Cederkall, J., Chulkov, L. V., Cortina-Gil, D., Cravo, E., Crespo, R., Dillmann, I., Fernández, P. Díaz, Elekes, Z., Enders, J., Farinon, F., Fraile, L. M., Redondo, D. Galaviz, Geissel, H., Gernhäuser, R., Golubev, P., Göbel, K., Heil, M., Heine, M., Heinz, A., Henriques, A., Holl, M., Johansson, H. T., Jonson, B., Kalantar-Nayestanaki, N., Kanungo, R., Kelic-Heil, A., Kröll, T., Kurz, N., Langer, C., Bleis, T. Le, Machado, J. F. D. C., Marganiec-Gałazka, J., Nacher, E., Nilsson, T., Nociforo, C., Panin, V., Perea, A., Pietri, S. B., Plag, R., Reifarth, R., Revel, A., Ribeiro, G., Rigollet, C., Rossi, D. M., Savran, D., Scheit, H., Simon, H., Sorlin, O., Tengblad, O., Togano, Y., Vandebrouck, M., Volkov, V., Wheldon, F. Wamers C., Wilson, G. L., Winfield, J. S., Weick, H., Woods, P., Yakorev, D., Zhukov, M., Zilges, A., and Zuber, K.

Subjects
Nuclear Experiment
Abstract

The evolution of the traditional nuclear magic numbers away from the valley of stability is an active field of research. Experimental efforts focus on providing key spectroscopic information that will shed light into the structure of exotic nuclei and understanding the driving mechanism behind the shell evolution. In this work, we investigate the Z = 6 spin-orbit shell gap towards the neutron dripline. To do so, we employed $^{A}$N(p,2p)$^{A-1}$C quasi-free scattering reactions to measure the proton component of the 2$^+_1$ state of $^{16,18,20}$C. The experimental findings support the notion of a moderate reduction of the proton 1p$_{1/2}$-1p$_{3/2}$ spin-orbit splitting, at variance to recent claims for a prevalent Z = 6 magic number towards the neutron dripline., Comment: 27 pages, 5 figures, 2 tables. Submitted to Physics Letter B

Published
2020
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10. All-Arthroscopic Refixation of an Osteochondral Femoral Avulsion of the Anterior Cruciate Ligament with a Laxity-Minimizing Suture

Author

Horstmann H, Karkosch R, Plagge J, Smith T, and Petri M

Subjects
anterior cruciate ligament, femoral avulsion, arthroscopy, refixation, Sports medicine, RC1200-1245
Abstract

Hauke Horstmann, Roman Karkosch, Jochen Plagge, Tomas Smith, Maximilian Petri Department of Orthopedic Surgery, Hannover Medical School, Hannover, GermanyCorrespondence: Hauke Horstmann, Anna-von-Borries-Straße 1-7, Hannover, 30625, Germany, Tel +49 511 5354 568, Fax +49 511 5354 685, Email hauke.horstmann@diakovere.dePurpose: Torn anterior cruciate ligaments in children are rare injuries. The incidence of concomitant avulsion fracture in the skeletally immature patient is high. Reports of arthroscopic reconstruction in the literature are sparse.Case Presentation: We present the case of a femoral avulsion fracture of the anterior cruciate ligament in a seven-year-old girl. The patient underwent arthroscopic refixation with DynacordTM Suture and Suture Button. At a follow-up of 8 weeks, the patient had free range of motion and a stable knee, with a negative Lachman- and Pivot-Shift-test in particular.Conclusion: Refixation of femoral avulsion fracture can lead to good results. Open physes and size of the knee should be taken into account. Anatomic reconstruction is compulsory to receive bone on bone healing.Keywords: anterior cruciate ligament, femoral avulsion, arthroscopy, refixation

Published
2023

12. Electromagnetic properties of $^{21}$O for benchmarking nuclear Hamiltonians

Author

Heil, S., Petri, M., Vobig, K., Bazin, D., Belarge, J., Bender, P., Brown, B. A., Elder, R., Elman, B., Gade, A., Haylett, T., Holt, J. D., Hüther, T., Hufnagel, A., Iwasaki, H., Kobayashi, N., Loelius, C., Longfellow, B., Lunderberg, E., Mathy, M., Menéndez, J., Paschalis, S., Roth, R., Schwenk, A., Simonis, J., Syndikus, I., Weisshaar, D., and Whitmore, K.

Subjects
Nuclear Experiment, Nuclear Theory
Abstract

The structure of exotic nuclei provides valuable tests for state-of-the-art nuclear theory. In particular electromagnetic transition rates are more sensitive to aspects of nuclear forces and many-body physics than excitation energies alone. We report the first lifetime measurement of excited states in $^{21}$O, finding $\tau_{1/2^+}=420^{+35}_{-32}\text{(stat)}^{+34}_{-12}\text{(sys)}$\,ps. This result together with the deduced level scheme and branching ratio of several $\gamma$-ray decays are compared to both phenomenological shell-model and ab initio calculations based on two- and three-nucleon forces derived from chiral effective field theory. We find that the electric quadrupole reduced transition probability of $\rm B(E2;1/2^+ \rightarrow 5/2^+_{g.s.}) = 0.71^{+0.07\ +0.02}_{-0.06\ -0.06}$~e$^2$fm$^4$, derived from the lifetime of the $1/2^+$ state, is smaller than the phenomenological result where standard effective charges are employed, suggesting the need for modifications of the latter in neutron-rich oxygen isotopes. We compare this result to both large-space and valence-space ab initio calculations, and by using multiple input interactions we explore the sensitivity of this observable to underlying details of nuclear forces., Comment: 23 pages, 3 figures

Published
2019
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13. Probing the Z = 6 spin-orbit shell gap with (p,2p) quasi-free scattering reactions

Author

Syndikus, I, Petri, M, Macchiavelli, AO, Paschalis, S, Bertulani, CA, Aumann, T, Alvarez-Pol, H, Atar, L, Beceiro-Novo, S, Benlliure, J, Boillos, JM, Boretzky, K, Borge, MJG, Brown, BA, Caamaño, M, Caesar, C, Casarejos, E, Catford, W, Cederkall, J, Chakraborty, S, Chulkov, LV, Cortina-Gil, D, Cravo, E, Crespo, R, Datta Pramanik, U, Dillmann, I, Díaz Fernández, P, Elekes, Z, Enders, J, Farinon, F, Fraile, LM, Galaviz, D, Geissel, H, Gernhäuser, R, Golubev, P, Göbel, K, Heil, M, Heine, M, Heinz, A, Henriques, A, Holl, M, Johansson, HT, Jonson, B, Kalantar-Nayestanaki, N, Kanungo, R, Kelic-Heil, A, Kröll, T, Kurz, N, Langer, C, Le Bleis, T, Machado, J, Marganiec-Gałązka, J, Nacher, E, Nilsson, T, Nociforo, C, Panin, V, Perea, A, Pietri, SB, Plag, R, Rahaman, A, Reifarth, R, Revel, A, Ribeiro, G, Rigollet, C, Rossi, DM, Savran, D, Scheit, H, Simon, H, Sorlin, O, Tengblad, O, Togano, Y, Vandebrouck, M, Volkov, V, Wamers, F, Wheldon, C, Wilson, GL, Winfield, JS, Weick, H, Woods, P, Yakorev, D, Zhukov, M, Zilges, A, and Zuber, K

Subjects
Mathematical Physics, Astronomical and Space Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Nuclear & Particles Physics
Abstract

The evolution of the traditional nuclear magic numbers away from the valley of stability is an active field of research. Experimental efforts focus on providing key spectroscopic information that will shed light into the structure of exotic nuclei and understanding the driving mechanism behind the shell evolution. In this work, we investigate the Z=6 spin-orbit shell gap towards the neutron dripline. To do so, we employed NA(p,2p)CA−1 quasi-free scattering reactions to measure the proton component of the 21+ state of 16,18,20C. The experimental findings support the notion of a moderate reduction of the proton 1p1/2−1p3/2 spin-orbit splitting, at variance to recent claims for a prevalent Z=6 magic number towards the neutron dripline.

Published
2020

14. Measurement of Nuclear Interaction Cross Sections towards Neutron-Skin Thickness Determination

Author

Ponnath, L., primary, Aumann, T., additional, Bertulani, C.A., additional, Gernhäuser, R., additional, Heil, M., additional, Almusidi, T., additional, Alvarez-Pol, H., additional, Atar, L., additional, Atkins, L., additional, Ayyad, Y., additional, Benlliure, J., additional, Boretzky, K., additional, Borge, M.J.G., additional, Bott, L.T., additional, Bruni, G., additional, Brückner, B., additional, Cabanelas, P., additional, Caesar, C., additional, Casarejos, E., additional, Cederkall, J., additional, Corsi, A., additional, Cortina-Gil, D., additional, Dueñas, J.A., additional, Duer, M., additional, Elekes, Z., additional, Escribano Rodriguez, S., additional, Fabbietti, L., additional, Falduto, A., additional, Feijoo, M., additional, Feijoo Fontan, M., additional, Fonseca, L.M., additional, Frotscher, A., additional, Galaviz, D., additional, Galiana, E., additional, García-Jiménez, G., additional, Gašparic̀, I., additional, Geraci, E.I., additional, Gillibert, A., additional, Gnoffo, B., additional, González Caamaño, D., additional, Graña González, A., additional, Göbel, K., additional, Hartig, A.-L., additional, Heinz, A., additional, Hensel, T., additional, Holl, M., additional, Horvat, A., additional, Jedele, A., additional, Jelavic̀ Malenica, D., additional, Jenegger, T., additional, Johansson, H.T., additional, Jonson, B., additional, Kalantar-Nayestanaki, N., additional, Kelic-Heil, A., additional, Kiselev, O.A., additional, Klenze, P., additional, Kresan, D., additional, Kröll, T., additional, Kudaibergenova, E., additional, Kurtulgil, D., additional, Körper, D., additional, Labiche, M., additional, Langer, C., additional, Lihtar, I., additional, Litvinov, Yu.A., additional, Löher, B., additional, Mayer, J., additional, Murillo Morales, S., additional, Nacher, E., additional, Nilsson, T., additional, Obertelli, A., additional, Panin, V., additional, Park, J., additional, Paschalis, S., additional, Perea, A., additional, Petri, M., additional, Pirrone, S., additional, Pohl, T., additional, Reifarth, R., additional, Rhee, H.-B., additional, Rodriguez-Sanchez, J.L., additional, Rose, L., additional, Rossi, D.M., additional, Russotto, P., additional, Savran, D., additional, Scheit, H., additional, Simon, H., additional, Storck-Dutine, S., additional, Stott, A.M., additional, Sürder, C., additional, Taniuchi, R., additional, Tengblad, O., additional, Teubig, P., additional, Trache, L., additional, Trimarchi, M., additional, Törnqvist, H.T., additional, Varga, L., additional, Wagner, V., additional, and Wamers, F., additional

Published
2024
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15. Environmentally Induced Snow Transmittance Variations in the Photosynthetic Spectral Domain: Photobiological Implications for Subnivean Vegetation under Climate Warming Conditions

Author

Gladimir V. G. Baranoski and Petri M. Varsa

Subjects
snow, photosynthetically active radiation, transmittance, spectral quality, vegetation, Science
Abstract

Variations in the productivity of subnivean vegetation can substantially affect the ecology of regions more susceptible to increasing warming levels and lead to significant feedback effects on the global climate. Due to its importance, this topic is at the center of a broad scope of interdisciplinary studies supported by field and remote sensing observations. However, the current knowledge about environmental factors affecting the penetration of photosynthetically active radiation (PAR) through snow is still constrained by the paucity of transmittance data. In this work, we aim to further the understanding about these interconnected processes. We conduct a systematic investigation about the effects of independent and combined changes in key nivological characteristics, namely thickness, saturation, density and grain size, on snow transmittance in the photosynthetic spectral domain. Our investigation is carried out through controlled in silico (computational) experiments supported by measured radiometric data. Its outcomes unveil fundamental quantitative and qualitative trends related to the role played by these nivological characteristics on the spectral quality of transmitted PAR, which is quantified in terms of red to blue (R/B), red to far-red (R/FR) and blue to far-red (B/FR) ratios. These trends include increases in the R/B ratio as well as decreases in the R/FR and B/FR ratios following thickness reductions or grain size increases, with opposite variations in these ratios being observed for saturation or density increases. Accordingly, the pairing of our findings with in situ and remotely collected information contributes to cement the scientific foundation required for the effective assessment of cause-effect loops linking accentuated vegetation greening to accelerated rates of snow cover recession.

Published
2024
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16. Nucleon-nucleon correlations and the single-particle strength in atomic nuclei

Author

Paschalis, S., Petri, M., Macchiavelli, A. O., Hen, O., and Piasetzky, E.

Subjects
Nuclear Experiment, Nuclear Theory
Abstract

We propose a phenomenological approach to examine the role of short- and long-range nucleon-nucleon correlations in the quenching of single-particle strength in atomic nuclei and their evolution in asymmetric nuclei and neutron matter. These correlations are thought to be the reason for the quenching of spectroscopic factors observed in $\rm (e,e'p)$, $\rm (p,2p)$ and transfer reactions. We show that the recently observed increase of the high-momentum component of the protons in neutron-rich nuclei is consistent with the reduced proton spectroscopic factors. Our approach connects recent results on short-range correlations from high-energy electron scattering experiments with the quenching of spectroscopic factors and addresses for the first time quantitatively this intriguing question in nuclear physics, in particular regarding its isospin dependence. We also speculate about the nature of a {\sl quasi-proton} (nuclear polaron) in neutron matter and its kinetic energy, an important quantity for the properties of neutron stars.

Published
2018
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17. Strong neutron pairing in core+4n nuclei

Author

Revel, A., Marques, F. M., Sorlin, O., Aumann, T., Caesar, C., Holl, M., Panin, V., Vandebrouck, M., Wamers, F., Alvarez-Pol, H., Atar, L., Avdeichikov, V., Beceiro-Novo, S., Bemmerer, D., Benlliure, J., Bertulani, C. A., Boillos, J. M., Boretzky, K., Borge, M. J. G., Caamano, M., Casarejos, E., Catford, W. N., Cederkäll, J., Chartier, M., Chulkov, L., Cortina-Gil, D., Cravo, E., Crespo, R., Pramanik, U. Datta, Fernandez, P. Diaz, Dillmann, I., Elekes, Z., Enders, J., Ershova, O., Estrade, A., Farinon, F., Fraile, L. M., Freer, M., Galaviz, D., Geissel, H., Gernhauser, R., Golubev, P., Göbel, K., Hagdahl, J., Heftrich, T., Heil, M., Heine, M., Heinz, A., Henriques, A., Hufnagel, A., Ignatov, A., Johansson, H. T., Jonson, B., Kahlbow, J., Kalantar-Nayestanaki, N., Kanungo, R., Kelic-Heil, A., Knyazev, A., Kroll, T., Kurz, N., Labiche, M., Langer, C., Bleis, T. Le, Lemmon, R., Lindberg, S., Machado, J., Marganiec, J., Movsesyan, A., Nacher, E., Najafi, M., Nikolskii, E., Nilsson, T., Nociforo, C., Paschalis, S., Perea, A., Petri, M., Pietri, S., Plag, R., Reifarth, R., Ribeiro, G., Rigollet, C., Roder, M., Rossi, D., Savran, D., Scheit, H., Simon, H., Syndikus, I., Taylor, J. T., Tengblad, O., Thies, R., Togano, Y., Velho, P., Volkov, V., Wagner, A., Weick, H., Wheldon, C., Wilson, G., Winfield, J. S., Woods, P., Yakorev, D., Zhukov, M., Zilges, A., and Zuber, K.

Subjects
Nuclear Experiment
Abstract

The emission of neutron pairs from the neutron-rich $N\!=\!12$ isotones $^{18}$C and $^{20}$O has been studied by high-energy nucleon knockout from $^{19}$N and $^{21}$O secondary beams, populating unbound states of the two isotones up to 15~MeV above their two-neutron emission thresholds. The analysis of triple fragment-$n$-$n$ correlations shows that the decay $^{19}$N$(-1p)^{18}$C$^*\!\rightarrow^{16}$C+$n$+$n$ is clearly dominated by direct pair emission. The two-neutron correlation strength, the largest ever observed, suggests the predominance of a $^{14}$C core surrounded by four valence neutrons arranged in strongly correlated pairs. On the other hand, a significant competition of a sequential branch is found in the decay $^{21}$O$(-1n)^{20}$O$^*\!\rightarrow^{18}$O+$n$+$n$, attributed to its formation through the knockout of a deeply-bound neutron that breaks the $^{16}$O core and reduces the number of pairs., Comment: 6 pages, 4 figures, accepted for publication in Phys. Rev. Lett

Published
2018
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18. Re-examining the transition into the N=20 island of inversion: structure of $^{30}$Mg

Author

Fernández-Domínguez, B., Pietras, B., Catford, W. N., Orr, N. A., Petri, M., Chartier, M., Paschalis, S., Patterson, N., Thomas, J . S., Caamaño, M., Otsuka, T., Poves, A., Tsunoda, N., Achouri, N. L., Angélique, J-C., Ashwood, N. I., Banu, A ., Bastin, B., Borcea, R., Brown, J., Delaunay, F., Franchoo, S., Freer, M., Gaudefroy, L., Heil, S., Labiche, M., Laurent, B., Lemmon, R. C., Macchiavelli, A. O., Negoita, F., Paul, E. S., Rodríguez-Tajes, C., Roussel-Chomaz, P., Staniou, M., Taylor, M. J., Trache, L., and Wilson, G. L.

Subjects
Nuclear Experiment, Nuclear Theory
Abstract

Intermediate energy single-neutron removal from $^{31}$Mg has been employed to investigate the transition into the N=20 island of inversion. Levels up to 5~MeV excitation energy in $^{30}$Mg were populated and spin-parity assignments were inferred from the corresponding longitudinal momentum distributions and $\gamma$-ray decay scheme. Comparison with eikonal-model calculations also permitted spectroscopic factors to be deduced. Surprisingly, the 0$^{+}_{2}$ level in $^{30}$Mg was found to have a strength much weaker than expected in the conventional picture of a predominantly $2p - 2h$ intruder configuration having a large overlap with the deformed $^{31}$Mg ground state. In addition, negative parity levels were identified for the first time in $^{30}$Mg, one of which is located at low excitation energy. The results are discussed in the light of shell-model calculations employing two newly developed approaches with markedly different descriptions of the structure of $^{30}$Mg. It is concluded that the cross-shell effects in the region of the island of inversion at Z=12 are considerably more complex than previously thought and that $np - nh$ configurations play a major role in the structure of $^{30}$Mg., Comment: Physics Letters B, Volume 779, 10 April 2018, Pages 124-129

Published
2018
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19. Nucleon-nucleon correlations and the single-particle strength in atomic nuclei

Author

Paschalis, S, Petri, M, Macchiavelli, AO, Hen, O, and Piasetzky, E

Subjects
Mathematical Physics, Astronomical and Space Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Nuclear & Particles Physics
Abstract

We propose a phenomenological approach to examine the role of short- and long-range nucleon-nucleon correlations in the quenching of single-particle strength in atomic nuclei and their evolution in asymmetric nuclei and neutron matter. These correlations are thought to be the reason for the quenching of spectroscopic factors observed in (e,e′p), (p,2p) and transfer reactions. We show that the recently observed increase of the high-momentum component of the protons in neutron-rich nuclei is consistent with the reduced proton spectroscopic factors. Our approach connects recent results on short-range correlations from high-energy electron scattering experiments with the quenching of spectroscopic factors and addresses for the first time quantitatively this intriguing question in nuclear physics, in particular regarding its isospin dependence. We also speculate about the nature of a quasi-proton (nuclear polaron) in neutron matter and its kinetic energy, an important quantity for the properties of neutron stars.

Published
2020

20. First Spectroscopy of the Near Drip-line Nucleus Mg40

Author

Crawford, HL, Fallon, P, Macchiavelli, AO, Doornenbal, P, Aoi, N, Browne, F, Campbell, CM, Chen, S, Clark, RM, Cortés, ML, Cromaz, M, Ideguchi, E, Jones, MD, Kanungo, R, MacCormick, M, Momiyama, S, Murray, I, Niikura, M, Paschalis, S, Petri, M, Sakurai, H, Salathe, M, Schrock, P, Steppenbeck, D, Takeuchi, S, Tanaka, YK, Taniuchi, R, Wang, H, and Wimmer, K

Subjects
Mathematical Sciences, Physical Sciences, Engineering, General Physics, Mathematical sciences, Physical sciences
Abstract

One of the most exotic light neutron-rich nuclei currently accessible for experimental study is ^{40}Mg, which lies at the intersection of the nucleon magic number N=28 and the neutron drip line. Low-lying excited states of ^{40}Mg have been studied for the first time following a one-proton removal reaction from ^{41}Al, performed at the Radioactive Isotope Beam Factory of RIKEN Nishina Center with the DALI2 γ-ray array and the ZeroDegree spectrometer. Two γ-ray transitions were observed, suggesting an excitation spectrum that shows unexpected properties as compared to both the systematics along the Z=12, N≥20  Mg isotopes and available state-of-the-art theoretical model predictions. A possible explanation for the observed structure involves weak-binding effects in the low-lying excitation spectrum.

Published
2019

21. First Spectroscopy of the Near Drip-line Nucleus ^{40}Mg.

Author

Crawford, HL, Fallon, P, Macchiavelli, AO, Doornenbal, P, Aoi, N, Browne, F, Campbell, CM, Chen, S, Clark, RM, Cortés, ML, Cromaz, M, Ideguchi, E, Jones, MD, Kanungo, R, MacCormick, M, Momiyama, S, Murray, I, Niikura, M, Paschalis, S, Petri, M, Sakurai, H, Salathe, M, Schrock, P, Steppenbeck, D, Takeuchi, S, Tanaka, YK, Taniuchi, R, Wang, H, and Wimmer, K

Subjects
Physical Sciences, General Physics, Mathematical Sciences, Engineering
Abstract

One of the most exotic light neutron-rich nuclei currently accessible for experimental study is ^{40}Mg, which lies at the intersection of the nucleon magic number N=28 and the neutron drip line. Low-lying excited states of ^{40}Mg have been studied for the first time following a one-proton removal reaction from ^{41}Al, performed at the Radioactive Isotope Beam Factory of RIKEN Nishina Center with the DALI2 γ-ray array and the ZeroDegree spectrometer. Two γ-ray transitions were observed, suggesting an excitation spectrum that shows unexpected properties as compared to both the systematics along the Z=12, N≥20  Mg isotopes and available state-of-the-art theoretical model predictions. A possible explanation for the observed structure involves weak-binding effects in the low-lying excitation spectrum.

Published
2019

23. Effective proton-neutron interaction near the drip line from unbound states in $^{25,26}$F

Author

Vandebrouck, M., Lepailleur, A., Sorlin, O., Aumann, T., Caesar, C., Holl, M., Panin, V., Wamers, F., Stroberg, S. R., Holt, J. D., Santos, F. De Oliveira, Alvarez-Pol, H., Atar, L., Avdeichikov, V., Beceiro-Novo, S., Bemmerer, D., Benlliure, J., Bertulani, C. A., Bogner, S. K., Boillos, J. M., Boretzky, K., Borge, M. J. G., Caamano, M., Casarejos, E., Catford, W., Cederkäll, J., Chartier, M., Chulkov, L., Cortina-Gil, D., Cravo, E., Crespo, R., Pramanik, U. Datta, Fernandez, P. Diaz, Dillmann, I., Elekes, Z., Enders, J., Ershova, O., Estrade, A., Farinon, F., Fraile, L. M., Freer, M., Galaviz, D., Geissel, H., Gernhauser, R., Gibelin, J., Golubev, P., Göbel, K., Hagdahl, J., Heftrich, T., Heil, M., Heine, M., Heinz, A., Henriques, A., Hergert, H., Hufnagel, A., Ignatov, A., Johansson, H. T., Jonson, B., Kahlbow, J., Kalantar-Nayestanaki, N., Kanungo, R., Kelic-Heil, A., Knyazev, A., Kröll, T., Kurz, N., Labiche, M., Langer, C., Bleis, T. Le, Lemmon, R., Lindberg, S., Machado, J., Marganiec, J., Marques, F. M., Movsesyan, A., Nacher, E., Najafi, M., Nikolskii, E., Nilsson, T., Nociforo, C., Paschalis, S., Perea, A., Petri, M., Pietri, S., Plag, R., Reifarth, R., Ribeiro, G., Rigollet, C., Röder, M., Rossi, D., Savran, D., Scheit, H., Schwenk, A., Simon, H., Syndikus, I., Taylor, J., Tengblad, O., Thies, R., Togano, Y., Velho, P., Volkov, V., Wagner, A., Weick, H., Wheldon, C., Wilson, G., Winfield, J. S., Woods, P., Yakorev, D., Zhukov, M., Zilges, A., and Zuber, K.

Subjects
Nuclear Experiment
Abstract

Background: Odd-odd nuclei, around doubly closed shells, have been extensively used to study proton-neutron interactions. However, the evolution of these interactions as a function of the binding energy, ultimately when nuclei become unbound, is poorly known. The $^{26}$F nucleus, composed of a deeply bound $\pi0d\_{5/2}$ proton and an unbound $\nu0d\_{3/2}$ neutron on top of an $^{24}$O core, is particularly adapted for this purpose. The coupling of this proton and neutron results in a $J^{\pi} = 1^{+}\_1 - 4^{+}\_1$ multiplet, whose energies must be determined to study the influence of the proximity of the continuum on the corresponding proton-neutron interaction. The $J^{\pi} = 1^{+}\_1, 2^{+}\_1,4^{+}\_1$ bound states have been determined, and only a clear identification of the $J^{\pi} =3^{+}\_1$ is missing.Purpose: We wish to complete the study of the $J^{\pi} = 1^{+}\_1 - 4^{+}\_1$ multiplet in $^{26}$F, by studying the energy and width of the $J^{\pi} =3^{+}\_1$ unbound state. The method was firstly validated by the study of unbound states in $^{25}$F, for which resonances were already observed in a previous experiment.Method: Radioactive beams of $^{26}$Ne and $^{27}$Ne, produced at about $440A$\,MeV by the FRagment Separator at the GSI facility, were used to populate unbound states in $^{25}$F and $^{26}$F via one-proton knockout reactions on a CH$\_2$ target, located at the object focal point of the R$^3$B/LAND setup. The detection of emitted $\gamma$-rays and neutrons, added to the reconstruction of the momentum vector of the $A-1$ nuclei, allowed the determination of the energy of three unbound states in $^{25}$F and two in $^{26}$F. Results: Based on its width and decay properties, the first unbound state in $^{25}$F is proposed to be a $J^{\pi} = 1/2^-$ arising from a $p\_{1/2}$ proton-hole state. In $^{26}$F, the first resonance at 323(33)~keV is proposed to be the $J^{\pi} =3^{+}\_1$ member of the $J^{\pi} = 1^{+}\_1 - 4^{+}\_1$ multiplet. Energies of observed states in $^{25,26}$F have been compared to calculations using the independent-particle shell model, a phenomenological shell-model, and the ab initio valence-space in-medium similarity renormalization group method.Conclusions: The deduced effective proton-neutron interaction is weakened by about 30-40\% in comparison to the models, pointing to the need of implementing the role of the continuum in theoretical descriptions, or to a wrong determination of the atomic mass of $^{26}$F., Comment: 14 pages, 7 figures, 3 tables, submitted to PRC

Published
2017
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24. Intruder configurations of excited states in the neutron-rich isotopes P 33 and P 34

Author

Lubna, RS, Tripathi, V, Tabor, SL, Tai, PL, Kravvaris, K, Bender, PC, Volya, A, Bouhelal, M, Chiara, CJ, Carpenter, MP, Janssens, RVF, Lauritsen, T, McCutchan, EA, Zhu, S, Clark, RM, Fallon, P, MacChiavelli, AO, Paschalis, S, Petri, M, Reviol, W, and Sarantites, DG

Abstract

Excited states in the neutron-rich isotopes P33 and P34 were populated by the O18+O18 fusion-evaporation reaction at Elab=24 MeV. The Gammasphere array was used along with the Microball particle detector array to detect γ transitions in coincidence with the charged particles emitted from the compound nucleus S36. The use of Microball enabled the selection of the proton emission channel. It also helped in determining the exact position and energy of the emitted proton; this was later employed in kinematic Doppler corrections. 16 new transitions and 13 new states were observed in P33 and 21 γ rays and 20 energy levels were observed in P34 for the first time. The nearly 4π geometry of Gammasphere allowed the measurement of γ-ray angular distributions leading to spin assignments for many states. The experimental observations for both isotopes were interpreted with the help of shell-model calculations using the (0+1)ω PSDPF interaction. The calculations accounted for both the 0p-0h and 1p-1h states reasonably well and indicated that 2p-2h excitations might dominate the higher-spin configurations in both P33 and P34.

Published
2018

25. Intruder configurations of excited states in the neutron-rich isotopes P33 and P34

Author

Lubna, RS, Tripathi, Vandana, Tabor, SL, Tai, P-L, Kravvaris, K, Bender, PC, Volya, A, Bouhelal, M, Chiara, CJ, Carpenter, MP, Janssens, RVF, Lauritsen, T, McCutchan, EA, Zhu, S, Clark, RM, Fallon, P, Macchiavelli, AO, Paschalis, S, Petri, M, Reviol, W, and Sarantites, DG

Subjects
Atomic, Molecular, Nuclear, Particle and Plasma Physics, Nuclear & Particles Physics
Abstract

Excited states in the neutron-rich isotopes P33 and P34 were populated by the O18+O18 fusion-evaporation reaction at Elab=24 MeV. The Gammasphere array was used along with the Microball particle detector array to detect γ transitions in coincidence with the charged particles emitted from the compound nucleus S36. The use of Microball enabled the selection of the proton emission channel. It also helped in determining the exact position and energy of the emitted proton; this was later employed in kinematic Doppler corrections. 16 new transitions and 13 new states were observed in P33 and 21 γ rays and 20 energy levels were observed in P34 for the first time. The nearly 4π geometry of Gammasphere allowed the measurement of γ-ray angular distributions leading to spin assignments for many states. The experimental observations for both isotopes were interpreted with the help of shell-model calculations using the (0+1)ω PSDPF interaction. The calculations accounted for both the 0p-0h and 1p-1h states reasonably well and indicated that 2p-2h excitations might dominate the higher-spin configurations in both P33 and P34.

Published
2018

26. A new Time-of-flight detector for the R3B setup

Author

Heil, M., Kelić-Heil, A., Bott, L., Almusidi, T., Alvarez-Pol, H., Atar, L., Atkins, L., Aumann, T., Benlliure, J., Boretzky, K., Brückner, B., Cabanelas, P., Caesar, C., Casarejos, E., Cederkall, J., Chulkov, L., Corsi, A., Dueñas, J., Erbacher, P., Rodriguez, S. Escribano, Falduto, A., Feijoo, M., Frotscher, A., Frühauf, J., Gašparić, I., Borge, M. J. G., Gerbig, J., Gernhäuser, R., Gilbert, M., Glorius, J., Gnoffo, B., Göbel, K., Caamaño, D. Gonzalez, Grein, A., Hartig, A.-L., Heggen, H., Heine, M., Heinz, A., Holl, M., Homm, I., Horvat, A., Johansson, H. T., Jonson, B., Kalantar-Nayestanaki, N., Kamenyero, A., Khodaparast, A., Kiselev, O., Klenze, P., Knösel, M., Koch, K., Körper, D., Kröll, T., Kurtulgil, D., Kurz, N., Löher, B., Langer, C., Lehr, C., Litvinov, Y., Liu, H., Morales, S. Murillo, Nácher, E., Nilsson, T., Park, J., Paschalis, S., Pellegri, L., Perea, A., Petri, M., Pohl, T., Ponnath, L., Popočovski, R., Reifarth, R., Rhee, H.-B., Sanchez, J. L. Rodriguez, Rossi, D., Sürder, C., Sánchez-Benítez, A. M., Savran, D., Scheit, H., Simon, H., Slavkovská, Z., Storck-Dutine, S., Sun, Y., Törnqvist, H. T., Tanaka, J., Tengblad, O., Thomas, B., Varga, L., Volknandt, M., Wagner, V., Wamers, F., and Zanetti, L.

Published
2022
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31. Challenges in QCD matter physics - The Compressed Baryonic Matter experiment at FAIR

Author

CBM Collaboration, Ablyazimov, T., Abuhoza, A., Adak, R. P., Adamczyk, M., Agarwal, K., Aggarwal, M. M., Ahammed, Z., Ahmad, F., Ahmad, N., Ahmad, S., Akindinov, A., Akishin, P., Akishina, E., Akishina, T., Akishina, V., Akram, A., Al-Turany, M., Alekseev, I., Alexandrov, E., Alexandrov, I., Amar-Youcef, S., Anđelić, M., Andreeva, O., Andrei, C., Andronic, A., Anisimov, Yu., Appelshäuser, H., Argintaru, D., Atkin, E., Avdeev, S., Averbeck, R., Azmi, M. D., Baban, V., Bach, M., Badura, E., Bähr, S., Balog, T., Balzer, M., Bao, E., Baranova, N., Barczyk, T., Bartoş, D., Bashir, S., Baszczyk, M., Batenkov, O., Baublis, V., Baznat, M., Becker, J., Becker, K. -H., Belogurov, S., Belyakov, D., Bendarouach, J., Berceanu, I., Bercuci, A., Berdnikov, A., Berdnikov, Y., Berendes, R., Berezin, G., Bergmann, C., Bertini, D., Bertini, O., Beşliu, C., Bezshyyko, O., Bhaduri, P. P., Bhasin, A., Bhati, A. K., Bhattacharjee, B., Bhattacharyya, A., Bhattacharyya, T. K., Biswas, S., Blank, T., Blau, D., Blinov, V., Blume, C., Bocharov, Yu., Book, J., Breitner, T., Brüning, U., Brzychczyk, J., Bubak, A., Büsching, H., Bus, T., Butuzov, V., Bychkov, A., Byszuk, A., Cai, Xu, Cálin, M., Cao, Ping, Caragheorgheopol, G., Carević, I., Cătănescu, V., Chakrabarti, A., Chattopadhyay, S., Chaus, A., Chen, Hongfang, Chen, LuYao, Cheng, Jianping, Chepurnov, V., Cherif, H., Chernogorov, A., Ciobanu, M. I., Claus, G., Constantin, F., Csanád, M., D'Ascenzo, N., Das, Supriya, Das, Susovan, de Cuveland, J., Debnath, B., Dementiev, D., Deng, Wendi, Deng, Zhi, Deppe, H., Deppner, I., Derenovskaya, O., Deveaux, C. A., Deveaux, M., Dey, K., Dey, M., Dillenseger, P., Dobyrn, V., Doering, D., Dong, Sheng, Dorokhov, A., Dreschmann, M., Drozd, A., Dubey, A. K., Dubnichka, S., Dubnichkova, Z., Dürr, M., Dutka, L., Dželalija, M., Elsha, V. V., Emschermann, D., Engel, H., Eremin, V., Eşanu, T., Eschke, J., Eschweiler, D., Fan, Huanhuan, Fan, Xingming, Farooq, M., Fateev, O., Feng, Shengqin, Figuli, S. P. D., Filozova, I., Finogeev, D., Fischer, P., Flemming, H., Förtsch, J., Frankenfeld, U., Friese, V., Friske, E., Fröhlich, I., Frühauf, J., Gajda, J., Galatyuk, T., Gangopadhyay, G., Chávez, C. García, Gebelein, J., Ghosh, P., Ghosh, S. K., Gläßel, S., Goffe, M., Golinka-Bezshyyko, L., Golovatyuk, V., Golovnya, S., Golovtsov, V., Golubeva, M., Golubkov, D., Ramírez, A. Gómez, Gorbunov, S., Gorokhov, S., Gottschalk, D., Gryboś, P., Grzeszczuk, A., Guber, F., Gudima, K., Gumiński, M., Gupta, A., Gusakov, Yu., Han, Dong, Hartmann, H., He, Shue, Hehner, J., Heine, N., Herghelegiu, A., Herrmann, N., Heß, B., Heuser, J. M., Himmi, A., Höhne, C., Holzmann, R., Hu, Dongdong, Huang, Guangming, Huang, Xinjie, Hutter, D., Ierusalimov, A., Ilgenfritz, E. -M., Irfan, M., Ivanischev, D., Ivanov, M., Ivanov, P., Ivanov, Valery, Ivanov, Victor, Ivanov, Vladimir, Ivashkin, A., Jaaskelainen, K., Jahan, H., Jain, V., Jakovlev, V., Janson, T., Jiang, Di, Jipa, A., Kadenko, I., Kähler, P., Kämpfer, B., Kalinin, V., Kallunkathariyil, J., Kampert, K. -H., Kaptur, E., Karabowicz, R., Karavichev, O., Karavicheva, T., Karmanov, D., Karnaukhov, V., Karpechev, E., Kasiński, K., Kasprowicz, G., Kaur, M., Kazantsev, A., Kebschull, U., Kekelidze, G., Khan, M. M., Khan, S. A., Khanzadeev, A., Khasanov, F., Khvorostukhin, A., Kirakosyan, V., Kirejczyk, M., Kiryakov, A., Kiš, M., Kisel, I., Kisel, P., Kiselev, S., Kiss, T., Klaus, P., Kłeczek, R., Klein-Bösing, Ch., Kleipa, V., Klochkov, V., Kmon, P., Koch, K., Kochenda, L., Koczoń, P., Koenig, W., Kohn, M., Kolb, B. W., Kolosova, A., Komkov, B., Korolev, M., Korolko, I., Kotte, R., Kovalchuk, A., Kowalski, S., Koziel, M., Kozlov, G., Kozlov, V., Kramarenko, V., Kravtsov, P., Krebs, E., Kreidl, C., Kres, I., Kresan, D., Kretschmar, G., Krieger, M., Kryanev, A. V., Kryshen, E., Kuc, M., Kucewicz, W., Kucher, V., Kudin, L., Kugler, A., Kumar, Ajit, Kumar, Ashwini, Kumar, L., Kunkel, J., Kurepin, A., Kurepin, N., Kurilkin, A., Kurilkin, P., Kushpil, V., Kuznetsov, S., Kyva, V., Ladygin, V., Lara, C., Larionov, P., García, A. Laso, Lavrik, E., Lazanu, I., Lebedev, A., Lebedev, S., Lebedeva, E., Lehnert, J., Lehrbach, J., Leifels, Y., Lemke, F., Li, Cheng, Li, Qiyan, Li, Xin, Li, Yuanjing, Lindenstruth, V., Linnik, B., Liu, Feng, Lobanov, I., Lobanova, E., Löchner, S., Loizeau, P. -A., Lone, S. A., Martínez, J. A. Lucio, Luo, Xiaofeng, Lymanets, A., Lyu, Pengfei, Maevskaya, A., Mahajan, S., Mahapatra, D. P., Mahmoud, T., Maj, P., Majka, Z., Malakhov, A., Malankin, E., Malkevich, D., Malyatina, O., Malygina, H., Mandal, M. M., Mandal, S., Manko, V., Manz, S., Garcia, A. M. Marin, Markert, J., Masciocchi, S., Matulewicz, T., Meder, L., Merkin, M., Mialkovski, V., Michel, J., Miftakhov, N., Mik, L., Mikhailov, K., Mikhaylov, V., Milanović, B., Militsija, V., Miskowiec, D., Momot, I., Morhardt, T., Morozov, S., Müller, W. F. J., Müntz, C., Mukherjee, S., Castillo, C. E. Muńoz, Murin, Yu., Najman, R., Nandi, C., Nandy, E., Naumann, L., Nayak, T., Nedosekin, A., Negi, V. S., Niebur, W., Nikulin, V., Normanov, D., Oancea, A., Oh, Kunsu, Onishchuk, Yu., Ososkov, G., Otfinowski, P., Ovcharenko, E., Pal, S., Panasenko, I., Panda, N. R., Parzhitskiy, S., Patel, V., Pauly, C., Penschuck, M., Peshekhonov, D., Peshekhonov, V., Petráček, V., Petri, M., Petriş, M., Petrovici, A., Petrovici, M., Petrovskiy, A., Petukhov, O., Pfeifer, D., Piasecki, K., Pieper, J., Pietraszko, J., Płaneta, R., Plotnikov, V., Plujko, V., Pluta, J., Pop, A., Pospisil, V., Poźniak, K., Prakash, A., Prasad, S. K., Prokudin, M., Pshenichnov, I., Pugach, M., Pugatch, V., Querchfeld, S., Rabtsun, S., Radulescu, L., Raha, S., Rami, F., Raniwala, R., Raniwala, S., Raportirenko, A., Rautenberg, J., Rauza, J., Ray, R., Razin, S., Reichelt, P., Reinecke, S., Reinefeld, A., Reshetin, A., Ristea, C., Ristea, O., Rodriguez, A. Rodriguez, Roether, F., Romaniuk, R., Rost, A., Rostchin, E., Rostovtseva, I., Roy, Amitava, Roy, Ankhi, Rożynek, J., Ryabov, Yu., Sadovsky, A., Sahoo, R., Sahu, P. K., Sahu, S. K., Saini, J., Samanta, S., Sambyal, S. S., Samsonov, V., Rosado, J. Sánchez, Sander, O., Sarangi, S., Satława, T., Sau, S., Saveliev, V., Schatral, S., Schiaua, C., Schintke, F., Schmidt, C. J., Schmidt, H. R., Schmidt, K., Scholten, J., Schweda, K., Seck, F., Seddiki, S., Selyuzhenkov, I., Semennikov, A., Senger, A., Senger, P., Shabanov, A., Shabunov, A., Shao, Ming, Sheremetiev, A. D., Shi, Shusu, Shumeiko, N., Shumikhin, V., Sibiryak, I., Sikora, B., Simakov, A., Simon, C., Simons, C., Singaraju, R. N., Singh, A. K., Singh, B. K., Singh, C. P., Singhal, V., Singla, M., Sitzmann, P., Siwek-Wilczyńska, K., Škoda, L., Skwira-Chalot, I., Som, I., Song, Guofeng, Song, Jihye, Sosin, Z., Soyk, D., Staszel, P., Strikhanov, M., Strohauer, S., Stroth, J., Sturm, C., Sultanov, R., Sun, Yongjie, Svirida, D., Svoboda, O., Szabó, A., Szczygieł, R., Talukdar, R., Tang, Zebo, Tanha, M., Tarasiuk, J., Tarassenkova, O., Târzilă, M. -G., Teklishyn, M., Tischler, T., Tlustý, P., Tölyhi, T., Toia, A., Topil'skaya, N., Träger, M., Tripathy, S., Tsakov, I., Tsyupa, Yu., Turowiecki, A., Tuturas, N. G., Uhlig, F., Usenko, E., Valin, I., Varga, D., Vassiliev, I., Vasylyev, O., Verbitskaya, E., Verhoeven, W., Veshikov, A., Visinka, R., Viyogi, Y. P., Volkov, S., Volochniuk, A., Vorobiev, A., Voronin, Aleksey, Voronin, Alexander, Vovchenko, V., Vznuzdaev, M., Wang, Dong, Wang, Xi-Wei, Wang, Yaping, Wang, Yi, Weber, M., Wendisch, C., Wessels, J. P., Wiebusch, M., Wiechula, J., Wielanek, D., Wieloch, A., Wilms, A., Winckler, N., Winter, M., Wiśniewski, K., Wolf, Gy., Won, Sanguk, Wu, Ke-Jun, Wüstenfeld, J., Xiang, Changzhou, Xu, Nu, Yang, Junfeng, Yang, Rongxing, Yin, Zhongbao, Yoo, In-Kwon, Yuldashev, B., Yushmanov, I., Zabołotny, W., Zaitsev, Yu., Zamiatin, N. I., Zanevsky, Yu., Zhalov, M., Zhang, Yifei, Zhang, Yu, Zhao, Lei, Zheng, Jiajun, Zheng, Sheng, Zhou, Daicui, Zhou, Jing, Zhu, Xianglei, Zinchenko, A., Zipper, W., Żoładź, M., Zrelov, P., Zryuev, V., Zumbruch, P., and Zyzak, M.

Subjects
Nuclear Experiment
Abstract

Substantial experimental and theoretical efforts worldwide are devoted to explore the phase diagram of strongly interacting matter. At LHC and top RHIC energies, QCD matter is studied at very high temperatures and nearly vanishing net-baryon densities. There is evidence that a Quark-Gluon-Plasma (QGP) was created at experiments at RHIC and LHC. The transition from the QGP back to the hadron gas is found to be a smooth cross over. For larger net-baryon densities and lower temperatures, it is expected that the QCD phase diagram exhibits a rich structure, such as a first-order phase transition between hadronic and partonic matter which terminates in a critical point, or exotic phases like quarkyonic matter. The discovery of these landmarks would be a breakthrough in our understanding of the strong interaction and is therefore in the focus of various high-energy heavy-ion research programs. The Compressed Baryonic Matter (CBM) experiment at FAIR will play a unique role in the exploration of the QCD phase diagram in the region of high net-baryon densities, because it is designed to run at unprecedented interaction rates. High-rate operation is the key prerequisite for high-precision measurements of multi-differential observables and of rare diagnostic probes which are sensitive to the dense phase of the nuclear fireball. The goal of the CBM experiment at SIS100 (sqrt(s_NN) = 2.7 - 4.9 GeV) is to discover fundamental properties of QCD matter: the phase structure at large baryon-chemical potentials (mu_B > 500 MeV), effects of chiral symmetry, and the equation-of-state at high density as it is expected to occur in the core of neutron stars. In this article, we review the motivation for and the physics programme of CBM, including activities before the start of data taking in 2022, in the context of the worldwide efforts to explore high-density QCD matter., Comment: 15 pages, 11 figures. Published in European Physical Journal A

Published
2016
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32. Determination of the Neutron-Capture Rate of 17C for the R-process Nucleosynthesis

Author

Heine, M., Typel, S., Wu, M. -R., Adachi, T., Aksyutina, Y., Alcantara, J., Altstadt, S., Alvarez-Pol, H., Ashwood, N., Aumann, T., Avdeichikov, V., Barr, M., Beceiro-Novo, S., Bemmerer, D., Benlliure, J., Bertulani, C. A., Boretzky, K., Borge, M. J. G., Burgunder, G., Caamano, M., Caesar, C., Casarejos, E., Catford, W., Cederkäll, J., Chakraborty, S., Chartier, M., Chulkov, L. V., Cortina-Gil, D., Crespo, R., Pramanik, U. Datta, Fernandez, P. Diaz, Dillmann, I., Elekes, Z., Enders, J., Ershova, O., Estrade, A., Farinon, F., Fraile, L. M., Freer, M., Freudenberger, M., Fynbo, H. O. U., Galaviz, D., Geissel, H., Gernhäuser, R., Göbel, K., Golubev, P., Diaz, D. Gonzalez, Hagdahl, J., Heftrich, T., Heil, M., Heinz, A., Henriques, A., Holl, M., Ickert, G., Ignatov, A., Jakobsson, B., Johansson, H. T., Jonson, B., Kalantar-Nayestanaki, N., Kanungo, R., Kelic-Heil, A., Knöbel, R., Kröll, T., Krücken, R., Kurcewicz, J., Kurz, N., Labiche, M., Langer, C., Bleis, T. Le, Lemmon, R., Lepyoshkina, O., Lindberg, S., Machado, J., Marganiec, J., Martínez-Pinedo, G., Maroussov, V., Mostazo, M., Movsesyan, A., Najafi, A., Neff, T., Nilsson, T., Nociforo, C., Panin, V., Paschalis, S., Perea, A., Petri, M., Pietri, S., Plag, R., Prochazka, A., Rahaman, A., Rastrepina, G., Reifarth, R., Ribeiro, G., Ricciardi, M. V., Rigollet, C., Riisager, K., Röder, M., Rossi, D., del Rio, J. Sanchez, Savran, D., Scheit, H., Simon, H., Sorlin, O., Stoica, V., Streicher, B., Taylor, J. T., Tengblad, O., Terashima, S., Thies, R., Togano, Y., Uberseder, E., Van de Walle, J., Velho, P., Volkov, V., Wagner, A., Wamers, F., Weick, H., Weigand, M., Wheldon, C., Wilson, G., Wimmer, C., Winfield, J. S., Woods, P., Yakorev, D., Zhukov, M. V., Zilges, A., and Zuber, K.

Subjects
Nuclear Experiment, Astrophysics - Solar and Stellar Astrophysics
Abstract

With the R$^{3}$B-LAND setup at GSI we have measured exclusive relative-energy spectra of the Coulomb dissociation of $^{18}$C at a projectile energy around 425~AMeV on a lead target, which are needed to determine the radiative neutron-capture cross sections of $^{17}$C into the ground state of $^{18}$C. Those data have been used to constrain theoretical calculations for transitions populating excited states in $^{18}$C. This allowed to derive the astrophysical cross section $\sigma^{*}_{\mathrm{n}\gamma}$ accounting for the thermal population of $^{17}$C target states in astrophysical scenarios. The experimentally verified capture rate is significantly lower than those of previously obtained Hauser-Feshbach estimations at temperatures $T_{9}\leq{}1$~GK. Network simulations with updated neutron-capture rates and hydrodynamics according to the neutrino-driven wind model as well as the neutron-star merger scenario reveal no pronounced influence of neutron capture of $^{17}$C on the production of second- and third-peak elements in contrast to earlier sensitivity studies.

Published
2016
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33. Systematic investigation of projectile fragmentation using beams of unstable B and C isotopes

Author

Thies, R., Heinz, A., Adachi, T., Aksyutina, Y., Alcantara-Núñes, J., Altstadt, S., Alvarez-Pol, H., Ashwood, N., Aumann, T., Avdeichikov, V., Barr, M., Beceiro-Novo, S., Bemmerer, D., Benlliure, J., Bertulani, C. A., Boretzky, K., Borge, M. J. G., Burgunder, G., Caamano, M., Caesar, C., Casarejos, E., Catford, W., Cederkäll, J., Chakraborty, S., Chartier, M., Chulkov, L. V., Cortina-Gil, D., Crespo, R., Datta, U., Fernández, P. Díaz, Dillmann, I., Elekes, Z., Enders, J., Ershova, O., Estradé, A., Farinon, F., Fraile, L. M., Freer, M., Freudenberger, M., Fynbo, H. O. U., Galaviz, D., Geissel, H., Gernhäuser, R., Göbel, K., Golubev, P., Diaz, D. Gonzalez, Hagdahl, J., Heftrich, T., Heil, M., Heine, M., Henriques, A., Holl, M., Ickert, G., Ignatov, A., Jakobsson, B., Johansson, H. T., Jonson, B., Kalantar-Nayestanaki, N., Kanungo, R., Knöbel, R., Kröll, T., Krücken, R., Kurcewicz, J., Kurz, N., Labiche, M., Langer, C., Bleis, T. Le, Lemmon, R., Lepyoshkina, O., Lindberg, S., Machado, J., Marganiec, J., Maroussov, V., Mostazo, M., Movsesyan, A., Najafi, A., Nilsson, T., Nociforo, C., Panin, V., Paschalis, S., Perea, A., Petri, M., Pietri, S., Plag, R., Prochazka, A., Rahaman, A., Rastrepina, G., Reifarth, R., Ribeiro, G., Ricciardi, M. V., Rigollet, C., Riisager, K., Röder, M., Rossi, D., del Rio, J. Sanchez, Savran, D., Scheit, H., Simon, H., Sorlin, O., Stoica, V., Streicher, B., Taylor, J. T., Tengblad, O., Terashima, S., Togano, Y., Uberseder, E., Van de Walle, J., Velho, P., Volkov, V., Wagner, A., Wamers, F., Weick, H., Weigand, M., Wheldon, C., Wilson, G., Wimmer, C., Winfield, J. S., Woods, P., Yakorev, D., Zhukov, M. V., Zilges, A., and Zuber, K.

Subjects
Nuclear Experiment
Abstract

Background: Models describing nuclear fragmentation and fragmentation-fission deliver important input for planning nuclear physics experiments and future radioactive ion beam facilities. These models are usually benchmarked against data from stable beam experiments. In the future, two-step fragmentation reactions with exotic nuclei as stepping stones are a promising tool to reach the most neutron-rich nuclei, creating a need for models to describe also these reactions. Purpose: We want to extend the presently available data on fragmentation reactions towards the light exotic region on the nuclear chart. Furthermore, we want to improve the understanding of projectile fragmentation especially for unstable isotopes. Method: We have measured projectile fragments from 10,12-18C and 10-15B isotopes colliding with a carbon target. These measurements were all performed within one experiment, which gives rise to a very consistent dataset. We compare our data to model calculations. Results: One-proton removal cross sections with different final neutron numbers (1pxn) for relativistic 10,12-18C and 10-15B isotopes impinging on a carbon target. Comparing model calculations to the data, we find that EPAX is not able to describe the data satisfactorily. Using ABRABLA07 on the other hand, we find that the average excitation energy per abraded nucleon needs to be decreased from 27 MeV to 8.1 MeV. With that decrease ABRABLA07 describes the data surprisingly well. Conclusions: Extending the available data towards light unstable nuclei with a consistent set of new data have allowed for a systematic investigation of the role of the excitation energy induced in projectile fragmentation. Most striking is the apparent mass dependence of the average excitation energy per abraded nucleon. Nevertheless, this parameter, which has been related to final-state interactions, requires further study.

Published
2016
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34. Cross-shell excitations in Si 31

Author

Tai, PL, Tabor, SL, Lubna, RS, Kravvaris, K, Bender, PC, Tripathi, V, Volya, A, Carpenter, MP, Janssens, RVF, Lauritsen, T, McCutchan, EA, Zhu, S, Clark, RM, Fallon, P, Paschalis, S, Petri, M, Macchiavelli, AO, Reviol, W, and Sarantites, DG

Subjects
1.1 Normal biological development and functioning
Abstract

The Si31 nucleus was produced through the O18(O18, αn) fusion-evaporation reaction at Elab=24MeV. Evaporated α particles from the reaction were detected and identified in the Microball detector array for channel selection. Multiple γ-ray coincidence events were detected in Gammasphere. The energy and angle information for the α particles was used to determine the Si31 recoil kinematics on an event-by-event basis for a more accurate Doppler correction. A total of 22 new states and 52 new γ transitions were observed, including 14 from states above the neutron separation energy. The positive-parity states predicted by the shell-model calculations in the sd model space agree well with experiment. The negative-parity states were compared with shell-model calculations in the psdpf model space with some variations in the N=20 shell gap. The best agreement was found with a shell gap intermediate between that originally used for A≈20 nuclei and that previously adapted for P32,34. This variation suggests the need for a more universal cross-shell interaction.

Published
2017

36. Azoniafluorenones: A New Family of Two‐Electron Storage Electrolytes for Sustainable Near‐Neutral pH Aqueous Organic Flow Battery.

Author

Artault, Maxime, Gonzalez, Gabriel, Damlin, Pia, Toivola, Juho, Mailman, Aaron, Hannonen, Jenna, Pihko, Petri M, and Peljo, Pekka

Subjects
FLOW batteries, REDUCTION potential, BORONIC acids, ENERGY storage, SOLUBILITY
Abstract

Fluorenones are suitable candidates for negolytes in flow batteries, as they demonstrate the ability to store 2 electrons, and can achieve reversibility, solubility, and stability with appropriate molecular design. However, limitations persist such as the use of alkaline media, high redox potentials, and a limited scope for optimization. Herein, azoniafluorenones is reported as a novel class of negolytes. They can be readily accessed in a highly modular fashion from inexpensive commercially available materials (e.g., boronic acids). Variations in the substitution patterns reveal the 3‐substituted N‐alkylated AZON3, which demonstrates excellent solubility at neutral pH (1.64 m) with two low reversible redox potentials (−0.31 and −0.58 V vs Ag/AgCl). AZON3 exhibits high stability when evaluated at high concentration in a neutral supporting electrolyte (1 m in 3 m KCl), paired with BTMAP‐Fc on the positive side. Capacity retentions of 99.95% and 99.91% per cycle (99.35% and 99.21% per day) are achieved when cycling with 1 and 2 electrons, respectively, coupled with high volumetric capacity of 46.4 Ah L−1 (87% of capacity utilization). [ABSTRACT FROM AUTHOR]

Published
2024
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37. Angiogenesis‐elicited spectral responses of early invasive skin melanoma: Implications for the evaluation of lesion progression.

Author

Baranoski, Gladimir V. G. and Varsa, Petri M.

Abstract

Early invasive skin melanoma (EISM) associated with partial tumor invasion to the thin and optically complex papillary dermis (PD) represents a critical stage before the onset of metastasis. EISM lesions may be accompanied by angiogenesis, which can alter the PD's blood and fibril contents. A comprehensive understanding about these interconnected processes is essential for enhancing the efficacy of EISM optical evaluation methodologies. Employing a first‐principles computational approach supported by measured data, we systematically assess the impact that angiogenesis can have on the EISM's spectral responses. Our findings indicate that these responses are discernibly affected by angiogenesis under distinct physiological conditions, with more substantial tissue alterations leading to accentuated spectral changes in the 550–600 nm region. Accordingly, we propose the use of a customized low‐cost spectral index to monitor these processes. Furthermore, our investigation provides a high‐fidelity in silico platform for interdisciplinary research on the photobiology of evolving skin melanomas. [ABSTRACT FROM AUTHOR]

Published
2024
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38. Aliphatic Ketone Claisen Rearrangement: Troubleshooting the Transetherification Step by Identifying a Stable Acid Catalyst.

Author

Bruce, Veera K., Farshadfar, Kaveh, Rolig, Aino, Laasonen, Kari, and Pihko, Petri M.

Subjects
CLAISEN rearrangement, ACID catalysts, CATALYTIC activity, REARRANGEMENTS (Chemistry), KETONES, ALLYL alcohol
Abstract

After optimization for retention of catalytic activity, 4‐chlorobenzoic acid emerged as the optimal catalyst for the aliphatic ketone Claisen rearrangement. The optimal catalyst enables a one‐pot, metal‐free, catalytic protocol from allylic alcohols to γ,δ‐unsaturated ketones. The optimized process tolerates a range of substrates, including substituents with acid‐labile protecting groups. Reaction monitoring and DFT studies of the aliphatic ketone Claisen process agree that the ultimate rearrangement step typically has the highest activation barrier. [ABSTRACT FROM AUTHOR]

Published
2024
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43. Cardiovascular events prior to or early after diagnosis of systemic lupus erythematosus in the systemic lupus international collaborating clinics cohort

Author

Urowitz, MB, Gladman, DD, Anderson, NM, Su, J, Romero-Diaz, J, Bae, SC, Fortin, PR, Sanchez-Guerrero, J, Clarke, A, Bernatsky, S, Gordon, C, Hanly, JG, Wallace, DJ, Isenberg, D, Rahman, A, Merrill, J, Ginzler, E, Alarcón, GS, Fessler, BF, Petri, M, Bruce, IN, Khamashta, M, Aranow, C, Dooley, M, Manzi, S, Ramsey-Goldman, R, Sturfelt, G, Nived, O, Steinsson, K, Zoma, A, Ruiz-Irastorza, G, Lim, S, Kalunian, KC, Ỉnanç, M, van Vollenhoven, R, Ramos-Casals, M, Kamen, DL, Jacobsen, S, Peschken, C, Askanase, A, and Stoll, T

Subjects
Reproductive Medicine, Biomedical and Clinical Sciences, Prevention, Atherosclerosis, Lupus, Cardiovascular, Autoimmune Disease, Clinical Research, Evaluation of treatments and therapeutic interventions, 4.1 Discovery and preclinical testing of markers and technologies, Detection, screening and diagnosis, 6.1 Pharmaceuticals, Inflammatory and immune system, Cardiovascular Disease, Inflammation, Systemic Lupus Erythematosus, Clinical sciences, Immunology
Abstract

ObjectiveTo describe the frequency of myocardial infarction (MI) prior to the diagnosis of systemic lupus erythematosus (SLE) and within the first 2 years of follow-up.MethodsThe systemic lupus international collaborating clinics (SLICC) atherosclerosis inception cohort enters patients within 15 months of SLE diagnosis. MIs were reported and attributed on a specialised vascular event form. MIs were confirmed by one or more of the following: abnormal ECG, typical or atypical symptoms with ECG abnormalities and elevated enzymes (≥2 times upper limit of normal), or abnormal stress test, echocardiogram, nuclear scan or angiogram. Descriptive statistics were used.Results31 of 1848 patients who entered the cohort had an MI. Of those, 23 patients had an MI prior to SLE diagnosis or within the first 2 years of disease. Of the 23 patients studied, 60.9% were female, 78.3% were Caucasian, 8.7% black, 8.7% Hispanic and 4.3% other. The mean age at SLE diagnosis was 52.5±15.0 years. Of the 23 MIs that occurred, 16 MIs occurred at a mean of 6.1±7.0 years prior to diagnosis and 7 occurred within the first 2 years of follow-up. Risk factors associated with early MI in univariate analysis are male sex, Caucasian, older age at diagnosis, hypertension, hypercholesterolaemia, family history of MI and smoking. In multivariate analysis only age (OR=1.06 95% CI 1.03 to 1.09), hypertension (OR=5.01, 95% CI 1.38 to 18.23), hypercholesterolaemia (OR=4.43, 95% CI 1.51 to 12.99) and smoking (OR=7.50, 95% CI 2.38 to 23.57) remained significant risk factors.ConclusionsIn some patients with lupus, MI may develop even before the diagnosis of SLE or shortly thereafter, suggesting that there may be a link between autoimmune inflammation and atherosclerosis.

Published
2016

44. γ-ray decay from neutron-bound and unbound states in Mo95 and a novel technique for spin determination

Author

Wiedeking, M, Krtička, M, Bernstein, LA, Allmond, JM, Basunia, MS, Bleuel, DL, Harke, JT, Daub, BH, Fallon, P, Firestone, RB, Goldblum, BL, Hatarik, R, Lake, PT, Larsen, AC, Lee, I-Y, Lesher, SR, Paschalis, S, Petri, M, Phair, L, Scielzo, ND, and Volya, A

Subjects
Nuclear and Plasma Physics, Synchrotrons and Accelerators, Physical Sciences, Nuclear and plasma physics
Abstract

The emission of γ rays from neutron-bound and neutron-unbound states in Mo95, populated in the Mo94(d,p) reaction, has been investigated. Charged particles and γ radiation were detected with arrays of annular silicon and Clover-type high-purity Germanium detectors, respectively. Utilizing p-γ and p-γ-γ coincidences, the Mo95 level scheme was greatly enhanced with 102 new transitions and 43 new states. It agrees well with shell model calculations for excitation energies below ≈2 MeV. From p-γ coincidence data, a new method for the determination of spins of discrete levels is proposed. The method exploits the suppression of high-angular momentum neutron emission from levels with high spins populated in the (d,p) reaction above the neutron separation energy. Spins for almost all Mo95 levels below 2 MeV (and for a few levels above) have been determined with this method.

Published
2016

45. γ -ray decay from neutron-bound and unbound states in Mo 95 and a novel technique for spin determination

Author

Wiedeking, M, Krtička, M, Bernstein, LA, Allmond, JM, Basunia, MS, Bleuel, DL, Burke, JT, Daub, BH, Fallon, P, Firestone, RB, Goldblum, BL, Hatarik, R, Lake, PT, Larsen, AC, Lee, IY, Lesher, SR, Paschalis, S, Petri, M, Phair, L, Scielzo, ND, and Volya, A

Abstract

The emission of γ rays from neutron-bound and neutron-unbound states in Mo95, populated in the Mo94(d,p) reaction, has been investigated. Charged particles and γ radiation were detected with arrays of annular silicon and Clover-type high-purity Germanium detectors, respectively. Utilizing p-γ and p-γ-γ coincidences, the Mo95 level scheme was greatly enhanced with 102 new transitions and 43 new states. It agrees well with shell model calculations for excitation energies below ≈2 MeV. From p-γ coincidence data, a new method for the determination of spins of discrete levels is proposed. The method exploits the suppression of high-angular momentum neutron emission from levels with high spins populated in the (d,p) reaction above the neutron separation energy. Spins for almost all Mo95 levels below 2 MeV (and for a few levels above) have been determined with this method.

Published
2016

46. How sharp is the transition into the N=20 island of inversion for the Mg isotopes?

Author

Fernández-Domínguez, B., Pietras, B., Catford, W.N., Orr, N.A., Petri, M., Chartier, M., Paschalis, S., Patterson, N., Thomas, J.S., Caamaño, M., Otsuka, T., Poves, A., Tsunoda, N., Achouri, N.L., Angélique, J-C., Ashwood, N.I., Banu, A., Bastin, B., Borcea, R., Brown, J., Delaunay, F., Franchoo, S., Freer, M., Gaudefroy, L., Heil, S., Labiche, M., Laurent, B., Lemmon, R.C., Macchiavelli, A. O., Negoita, F., Paul, E.S., Rodríguez-Tajes, C., Roussel-Chomaz, P., Staniou, M., Taylor, M., Trache, L., Wilson, G.L., Fernández-Domínguez, B., Pietras, B., Catford, W.N., Orr, N.A., Petri, M., Chartier, M., Paschalis, S., Patterson, N., Thomas, J.S., Caamaño, M., Otsuka, T., Poves, A., Tsunoda, N., Achouri, N.L., Angélique, J-C., Ashwood, N.I., Banu, A., Bastin, B., Borcea, R., Brown, J., Delaunay, F., Franchoo, S., Freer, M., Gaudefroy, L., Heil, S., Labiche, M., Laurent, B., Lemmon, R.C., Macchiavelli, A. O., Negoita, F., Paul, E.S., Rodríguez-Tajes, C., Roussel-Chomaz, P., Staniou, M., Taylor, M., Trache, L., and Wilson, G.L.

Abstract

The N=20 island of inversion is an excellent playground for testing shell model calculations. The Mg chain is a region of shell evolution still far from being well understood. In this paper we present preliminary results of a single-neutron knockout experiment from ³¹Mg performed at GANIL to study the structure of ³¹Mg and of the core ³⁰Mg. The level scheme and longitudinal momentum distributions were mesured and spectroscopic factors were deduced. Negative parity states arise at low energy and the spectroscopic factor for the isomeric 0²₊ in ³⁰Mg was determined to be smaller than foreseen in the standard picture. The preliminary experimental results are compared to state-of the art shell model calculations revealing opposed interpretations.

Published
2024

47. Lifetime measurement of the ²⁶O g.s. at SAMURAI

Author

Storck, S., Caesar, C., Kahlbow, J., Panin, V., Ahn, D. S., Atar, L., Aumann, T., Baba, H., Boretzky’, K., Chae, H., Chiga, N., Choi, S., Cortés, M. L., Cortina-Gil, D., Deshayes, Q., Doornenbal, P., Elekes, Z., Fukuda, N., Gašparić, I., Hahn, K. I., Halász, Z., Hirayama, A., Hwang, J., Inabe, N., Isobe, T., Kim, S., Kobayashi, T., Körper, D., Marques, M., Matsumoto, M., Murakami, T., Murray, I., Nakamura, T., Nilsson, T., Otsu, H., Paschalis, S., Parlog, M., Petri, M., Rossi, D., Saito, A., Sasano, M., Scheit, H., Schrock, P., Shimizu, Y., Simon, H., Sohler, D., Sorlin, O., Stuhl, L., Suzuki, H., Syndikus, I., Takeda, H., Törnqvist, H., Togano, Y., Tomai, T., Uesaka, T., Yamada, H., Yang, Z., Yasuda, M., Yoneda, K. I., Storck, S., Caesar, C., Kahlbow, J., Panin, V., Ahn, D. S., Atar, L., Aumann, T., Baba, H., Boretzky’, K., Chae, H., Chiga, N., Choi, S., Cortés, M. L., Cortina-Gil, D., Deshayes, Q., Doornenbal, P., Elekes, Z., Fukuda, N., Gašparić, I., Hahn, K. I., Halász, Z., Hirayama, A., Hwang, J., Inabe, N., Isobe, T., Kim, S., Kobayashi, T., Körper, D., Marques, M., Matsumoto, M., Murakami, T., Murray, I., Nakamura, T., Nilsson, T., Otsu, H., Paschalis, S., Parlog, M., Petri, M., Rossi, D., Saito, A., Sasano, M., Scheit, H., Schrock, P., Shimizu, Y., Simon, H., Sohler, D., Sorlin, O., Stuhl, L., Suzuki, H., Syndikus, I., Takeda, H., Törnqvist, H., Togano, Y., Tomai, T., Uesaka, T., Yamada, H., Yang, Z., Yasuda, M., and Yoneda, K. I.

Abstract

The ground state of the neutron unbound nucleus ²⁶O is speculated to have a lifetime in the pico-second regime. In order to determine the decay lifetime of the ²⁶O ground state with high sensitivity and precision, a new method has been applied. The experiment was performed in December 2016 at the Superconducting Analyzer for MUlti-particle from Radio Isotope Beams (SAMURAI) at the Radioactive Isotope Beam Factory (RIBF) at RIKEN. A ²⁷F beam was produced in the fragment separator BigRIPS and impinged on a W/Pt target ²⁶O ²⁶O outside the target. Thus, the velocity difference between the decay neutrons and the fragment 1 O delivers a characteristic spectrum from which the lifetime can be extracted.

Published
2024

48. Competing particle-hole excitations in 30Na: Constraining state-of-the-art effective interactions

Author

Petri, M, Fallon, P, Macchiavelli, AO, Heil, S, Rodriguez-Vieitez, E, Bazin, D, Campbell, CM, Clark, RM, Cromaz, M, Gade, A, Glasmacher, T, Lee, IY, Malbrunot-Ettenauer, S, Paschalis, S, Ratkiewicz, A, Terry, JR, Weisshaar, D, and Wiedeking, M

Subjects
"Island of Inversion", Knockout reactions, Radioactive ion beams, Effective interaction, Particle-hole excitations, Negative parity, Nuclear & Particles Physics, Mathematical Physics, Astronomical and Space Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics
Abstract

The odd-odd nucleus 30Na is studied via a one-proton, one-proton-one-neutron and one-neutron removal reaction using an intermediate-energy 31Mg, 32Mg and 31Na radioactive ion beam, respectively. Combining high-resolution γ-ray spectroscopy with the selectivity of the three reaction mechanisms, we are able to distinguish multiple particle-hole configurations. Negative-parity states in 30Na are observed for the first time, providing an important measure of the excitation of the 1p1h/3p3h configuration and hence the sd-pf shell gap. The extracted band structures and level energies serve as invaluable input for the theoretical refinement of the effective interactions used in this region.

Published
2015

49. Triplet energy differences and the low lying structure of Ga 62

Author

Henry, TW, Bentley, MA, Clark, RM, Davies, PJ, Bader, VM, Baugher, T, Bazin, D, Beausang, CW, Berryman, JS, Bruce, AM, Campbell, CM, Crawford, HL, Cromaz, M, Fallon, P, Gade, A, Henderson, J, Iwasaki, H, Jenkins, DG, Lee, IY, Lemasson, A, Lenzi, SM, Macchiavelli, AO, Napoli, DR, Nichols, AJ, Paschalis, S, Petri, M, Recchia, F, Rissanen, J, Simpson, EC, Stroberg, SR, Wadsworth, R, Weisshaar, D, Wiens, A, and Walz, C

Subjects
Nuclear & Particles Physics, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Atomic, Molecular, Nuclear, Particle and Plasma Physics
Abstract

Background: Triplet energy differences (TED) can be studied to yield information on isospin-non-conserving interactions in nuclei. Purpose: The systematic behavior of triplet energy differences (TED) of T=1, Jπ=2+ states is examined. The A=62 isobar is identified as having a TED value that deviates significantly from an otherwise very consistent trend. This deviation can be attributed to the tentative assignments of the pertinent states in Ga62 and Ge62. Methods: An in-beam γ-ray spectroscopy experiment was performed to identify excited states in Ga62 using Gamma-Ray Energy Tracking In-Beam Nuclear Array with the S800 spectrometer at NSCL using a two-nucleon knockout approach. Cross-section calculations for the knockout process and shell-model calculations have been performed to interpret the population and decay properties observed. Results: Using the systematics as a guide, a candidate for the transition from the T=1, 2+ state is identified. However, previous work has identified similar states with different Jπ assignments. Cross-section calculations indicate that the relevant T=1, 2+ state should be one of the states directly populated in this reaction. Conclusions: As spins and parities were not measurable, it is concluded that an unambiguous identification of the first T=1, 2+ state is required to reconcile our understanding of TED systematics.

Published
2015

50. Nuclear astrophysics with radioactive ions at FAIR

Author

Reifarth, R., Altstadt, S., Göbel, K., Heftrich, T., Heil, M., Koloczek, A., Langer, C., Plag, R., Pohl, M., Sonnabend, K., Weigand, M., Adachi, T., Aksouh, F., Al-Khalili, J., AlGarawi, M., AlGhamdi, S., Alkhazov, G., Alkhomashi, N., Alvarez-Pol, H., Alvarez-Rodriguez, R., Andreev, V., Andrei, B., Atar, L., Aumann, T., Avdeichikov, V., Bacri, C., Bagchi, S., Barbieri, C., Beceiro, S., Beck, C., Beinrucker, C., Belier, G., Bemmerer, D., Bendel, M., Benlliure, J., Benzoni, G., Berjillos, R., Bertini, D., Bertulani, C., Bishop, S., Blasi, N., Bloch, T., Blumenfeld, Y., Bonaccorso, A., Boretzky, K., Botvina, A., Boudard, A., Boutachkov, P., Boztosun, I., Bracco, A., Brambilla, S., Monago, J. Briz, Caamano, M., Caesar, C., Camera, F., Casarejos, E., Catford, W., Cederkall, J., Cederwall, B., Chartier, M., Chatillon, A., Cherciu, M., Chulkov, L., Coleman-Smith, P., Cortina-Gil, D., Crespi, F., Crespo, R., Cresswell, J., Csatlós, M., Déchery, F., Davids, B., Davinson, T., Derya, V., Detistov, P., Fernandez, P. Diaz, DiJulio, D., Dmitry, S., Doré, D., Duenas, J., Dupont, E., Egelhof, P., Egorova, I., Elekes, Z., Enders, J., Endres, J., Ershov, S., Ershova, O., Fernandez-Dominguez, B., Fetisov, A., Fiori, E., Fomichev, A., Fonseca, M., Fraile, L., Freer, M., Friese, J., Borge, M. G., Redondo, D. Galaviz, Gannon, S., Garg, U., Gasparic, I., Gasques, L., Gastineau, B., Geissel, H., Gernhäuser, R., Ghosh, T., Gilbert, M., Glorius, J., Golubev, P., Gorshkov, A., Gourishetty, A., Grigorenko, L., Gulyas, J., Haiduc, M., Hammache, F., Harakeh, M., Hass, M., Heine, M., Hennig, A., Henriques, A., Herzberg, R., Holl, M., Ignatov, A., Ignatyuk, A., Ilieva, S., Ivanov, M., Iwasa, N., Jakobsson, B., Johansson, H., Jonson, B., Joshi, P., Junghans, A., Jurado, B., Körner, G., Kalantar, N., Kanungo, R., Kelic-Heil, A., Kezzar, K., Khan, E., Khanzadeev, A., Kiselev, O., Kogimtzis, M., Körper, D., Kräckmann, S., Kröll, T., Krücken, R., Krasznahorkay, A., Kratz, J., Kresan, D., Krings, T., Krumbholz, A., Krupko, S., Kulessa, R., Kumar, S., Kurz, N., Kuzmin, E., Labiche, M., Langanke, K., Lazarus, I., Bleis, T. Le, Lederer, C., Lemasson, A., Lemmon, R., Liberati, V., Litvinov, Y., Löher, B., Herraiz, J. Lopez, Münzenberg, G., Machado, J., Maev, E., Mahata, K., Mancusi, D., Marganiec, J., Perez, M. Martinez, Marusov, V., Mengoni, D., Million, B., Morcelle, V., Moreno, O., Movsesyan, A., Nacher, E., Najafi, M., Nakamura, T., Naqvi, F., Nikolski, E., Nilsson, T., Nociforo, C., Nolan, P., Novatsky, B., Nyman, G., Ornelas, A., Palit, R., Pandit, S., Panin, V., Paradela, C., Parkar, V., Paschalis, S., Pawłowski, P., Perea, A., Pereira, J., Petrache, C., Petri, M., Pickstone, S., Pietralla, N., Pietri, S., Pivovarov, Y., Potlog, P., Prokofiev, A., Rastrepina, G., Rauscher, T., Ribeiro, G., Ricciardi, M., Richter, A., Rigollet, C., Riisager, K., Rios, A., Ritter, C., Frutos, T. Rodríguez, Vignote, J. Rodriguez, Röder, M., Romig, C., Rossi, D., Roussel-Chomaz, P., Rout, P., Roy, S., Söderström, P., Sarkar, M. Saha, Sakuta, S., Salsac, M., Sampson, J., Saez, J. Sanchez del Rio, Rosado, J. Sanchez, Sanjari, S., Sarriguren, P., Sauerwein, A., Savran, D., Scheidenberger, C., Scheit, H., Schmidt, S., Schmitt, C., Schnorrenberger, L., Schrock, P., Schwengner, R., Seddon, D., Sherrill, B., Shrivastava, A., Sidorchuk, S., Silva, J., Simon, H., Simpson, E., Singh, P., Slobodan, D., Sohler, D., Spieker, M., Stach, D., Stan, E., Stanoiu, M., Stepantsov, S., Stevenson, P., Strieder, F., Stuhl, L., Suda, T., Sümmerer, K., Streicher, B., Taieb, J., Takechi, M., Tanihata, I., Taylor, J., Tengblad, O., Ter-Akopian, G., Terashima, S., Teubig, P., Thies, R., Thoennessen, M., Thomas, T., Thornhill, J., Thungstrom, G., Timar, J., Togano, Y., Tomohiro, U., Tornyi, T., Tostevin, J., Townsley, C., Trautmann, W., Trivedi, T., Typel, S., Uberseder, E., Udias, J., Uesaka, T., Uvarov, L., Vajta, Z., Velho, P., Vikhrov, V., Volknandt, M., Volkov, V., von Neumann-Cosel, P., von Schmid, M., Wagner, A., Wamers, F., Weick, H., Wells, D., Westerberg, L., Wieland, O., Wiescher, M., Wimmer, C., Wimmer, K., Winfield, J. S., Winkel, M., Woods, P., Wyss, R., Yakorev, D., Yavor, M., Cardona, J. Zamora, Zartova, I., Zerguerras, T., Zgura, I., Zhdanov, A., Zhukov, M., Zieblinski, M., Zilges, A., and Zuber, K.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics, Nuclear Experiment
Abstract

The nucleosynthesis of elements beyond iron is dominated by neutron captures in the s and r processes. However, 32 stable, proton-rich isotopes cannot be formed during those processes, because they are shielded from the s-process flow and r-process beta-decay chains. These nuclei are attributed to the p and rp process. For all those processes, current research in nuclear astrophysics addresses the need for more precise reaction data involving radioactive isotopes. Depending on the particular reaction, direct or inverse kinematics, forward or time-reversed direction are investigated to determine or at least to constrain the desired reaction cross sections. The Facility for Antiproton and Ion Research (FAIR) will offer unique, unprecedented opportunities to investigate many of the important reactions. The high yield of radioactive isotopes, even far away from the valley of stability, allows the investigation of isotopes involved in processes as exotic as the r or rp processes., Comment: Invited Talk given at the Conference Nuclear Physice in Astrophysics VI (NPA6), Lisbon, Portugal, May 19-24 2013. To appear in the NPA6 Proceedings in Journal of Physics: Conference Series (JPCS)

Published
2013
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