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2. 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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3. Nucleon-nucleon potentials in phase-space representation

Author

Feldmeier, H., Neff, T., and Weber, D.

Subjects
Nuclear Theory
Abstract

A phase-space representation of nuclear interactions, which depends on the distance $\vec{r}$ and relative momentum $\vec{p}$ of the nucleons, is presented. A method is developed that permits to extract the interaction $V(\vec{r},\vec{p})$ from antisymmetrized matrix elements given in a spherical basis with angular momentum quantum numbers, either in momentum or coordinate space representation. This representation visualizes in an intuitive way the non-local behavior introduced by cutoffs in momentum space or renormalization procedures that are used to adapt the interaction to low momentum many-body Hilbert spaces, as done in the unitary correlation operator method or with the similarity renormalization group. It allows to develop intuition about the various interactions and illustrates how the softened interactions reduce the short-range repulsion in favor of non-locality or momentum dependence while keeping the scattering phase shifts invariant. It also reveals that these effective interactions can have undesired complicated momentum dependencies at momenta around and above the Fermi momentum. Properties, similarities and differences of the phase-space representations of the Argonne and the N3LO chiral potential, and their UCOM and SRG derivatives are discussed.

Published
2014
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4. From nucleon-nucleon interaction matrix elements in momentum space to an operator representation

Author

Weber, D., Feldmeier, H., Hergert, H., and Neff, T.

Subjects
Nuclear Theory
Abstract

Starting from the matrix elements of the nucleon-nucleon interaction in momentum space we present a method to derive an operator representation with a minimal set of operators that is required to provide an optimal description of the partial waves with low angular momentum. As a first application we use this method to obtain an operator representation for the Argonne potential transformed by means of the unitary correlation operator method and discuss the necessity of including momentum dependent operators. The resulting operator representation leads to the same results as the original momentum space matrix elements when applied to the two-nucleon system and various light nuclei. For applications in fermionic and antisymmetrized molecular dynamics, where an operator representation of a soft but realistic effective interaction is indispensable, a simplified version using a reduced set of operators is given.

Published
2013
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5. Dynamical phase diagram of Gaussian BEC wave packets in optical lattices

Author

Hennig, H., Neff, T., and Fleischmann, R.

Subjects
Nonlinear Sciences - Pattern Formation and Solitons, Condensed Matter - Quantum Gases
Abstract

We study the dynamics of self-trapping in Bose-Einstein condensates (BECs) loaded in deep optical lattices with Gaussian initial conditions, when the dynamics is well described by the Discrete Nonlinear Schr\"odinger Equation (DNLS). In the literature an approximate dynamical phase diagram based on a variational approach was introduced to distinguish different dynamical regimes: diffusion, self-trapping and moving breathers. However, we find that the actual DNLS dynamics shows a completely different diagram than the variational prediction. We numerically calculate a detailed dynamical phase diagram accurately describing the different dynamical regimes. It exhibits a complex structure which can readily be tested in current experiments in BECs in optical lattices and in optical waveguide arrays. Moreover, we derive an explicit theoretical estimate for the transition to self-trapping in excellent agreement with our numerical findings, which may be a valuable guide as well for future studies on a quantum dynamical phase diagram based on the Bose-Hubbard Hamiltonian.

Published
2013
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6. Universality of short-range nucleon-nucleon correlations

Author

Feldmeier, H., Horiuchi, W., Neff, T., and Suzuki, Y.

Subjects
Nuclear Theory
Abstract

Short-range correlations between nucleon pairs in different spin-isospin channels are investigated for light nuclei using the Argonne V8' interaction. At distances below 1 fm a universal behavior is found for the deuteron, 3H, 3He and for ground and first excited states in 4He. This behavior in coordinate space is reflected by a universal behavior for the high-momentum components in momentum space. The universality indicates that a pairwise renormalization is possible in order to obtain a universal effective two-body interaction that does not scatter to high momentum states. The exact two-body densities are compared with those obtained using the unitary correlation operator method with simple trial wave functions. The effect of three-body correlations due to the tensor force on the two-body densities is discussed., Comment: 13 pages, 17 figures, journal version

Published
2011
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7. Pair decay width of the Hoyle state and carbon production in stars

Author

Chernykh, M., Feldmeier, H., Neff, T., von Neumann-Cosel, P., and Richter, A.

Subjects
Nuclear Experiment, Astrophysics - Solar and Stellar Astrophysics, Nuclear Theory
Abstract

Electron scattering off the first excited 0+ state in 12C (the Hoyle state) has been performed at low momentum transfers at the S-DALINAC. The new data together with a novel model-independent analysis of the world data set covering a wide momentum transfer range result in a highly improved transition charge density from which a pair decay width Gamma_pi = (62.3 +- 2.0) micro-eV of the Hoyle state was extracted reducing the uncertainty of the literature values by more than a factor of three. A precise knowledge of Gamma_pi is mandatory for quantitative studies of some key issues in the modeling of supernovae and of asymptotic giant branch stars, the most likely site of the slow-neutron nucleosynthesis process., Comment: 4 pages, 4 figures, accepted for publication in Phys. Rev. Lett

Published
2010
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8. Hartree-Fock and Many-Body Perturbation Theory with Correlated Realistic NN-Interactions

Author

Roth, R., Papakonstantinou, P., Paar, N., Hergert, H., Neff, T., and Feldmeier, H.

Subjects
Nuclear Theory
Abstract

We employ correlated realistic nucleon-nucleon interactions for the description of nuclear ground states throughout the nuclear chart within the Hartree-Fock approximation. The crucial short-range central and tensor correlations, which are induced by the realistic interaction and cannot be described by the Hartree-Fock many-body state itself, are included explicitly by a state-independent unitary transformation in the framework of the unitary correlation operator method (UCOM). Using the correlated realistic interaction V_UCOM resulting from the Argonne V18 potential, bound nuclei are obtained already on the Hartree-Fock level. However, the binding energies are smaller than the experimental values because long-range correlations have not been accounted for. Their inclusion by means of many-body perturbation theory leads to a remarkable agreement with experimental binding energies over the whole mass range from He-4 to Pb-208, even far off the valley of stability. The observed perturbative character of the residual long-range correlations and the apparently small net effect of three-body forces provides promising perspectives for a unified nuclear structure description., Comment: 14 pages, 8 figures, 3 tables, using REVTEX4

Published
2005
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9. Matrix Elements and Few-Body Calculations within the Unitary Correlation Operator Method

Author

Roth, R., Hergert, H., Papakonstantinou, P., Neff, T., and Feldmeier, H.

Subjects
Nuclear Theory
Abstract

We employ the Unitary Correlation Operator Method (UCOM) to construct correlated, low-momentum matrix elements of realistic nucleon-nucleon interactions. The dominant short-range central and tensor correlations induced by the interaction are included explicitly by an unitary transformation. Using correlated momentum-space matrix elements of the Argonne V18 potential, we show that the unitary transformation eliminates the strong off-diagonal contributions caused by the short-range repulsion and the tensor interaction, and leaves a correlated interaction dominated by low-momentum contributions. We use correlated harmonic oscillator matrix elements as input for no-core shell model calculations for few-nucleon systems. Compared to the bare interaction, the convergence properties are dramatically improved. The bulk of the binding energy can already be obtained in very small model spaces or even with a single Slater determinant. Residual long-range correlations, not treated explicitly by the unitary transformation, can easily be described in model spaces of moderate size allowing for fast convergence. By varying the range of the tensor correlator we are able to map out the Tjon line and can in turn constrain the optimal correlator ranges., Comment: 16 pages, 9 figures, using REVTEX4

Published
2005
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10. Nuclear Structure based on Correlated Realistic Nucleon-Nucleon Potentials

Author

Roth, R., Neff, T., Hergert, H., and Feldmeier, H.

Subjects
Nuclear Theory
Abstract

We present a novel scheme for nuclear structure calculations based on realistic nucleon-nucleon potentials. The essential ingredient is the explicit treatment of the dominant interaction-induced correlations by means of the Unitary Correlation Operator Method (UCOM). Short-range central and tensor correlations are imprinted into simple, uncorrelated many-body states through a state-independent unitary transformation. Applying the unitary transformation to the realistic Hamiltonian leads to a correlated, low-momentum interaction, well suited for all kinds of many-body models, e.g., Hartree-Fock or shell-model. We employ the correlated interaction, supplemented by a phenomenological correction to account for genuine three-body forces, in the framework of variational calculations with antisymmetrised Gaussian trial states (Fermionic Molecular Dynamics). Ground state properties of nuclei up to mass numbers A<~60 are discussed. Binding energies, charge radii, and charge distributions are in good agreement with experimental data. We perform angular momentum projections of the intrinsically deformed variational states to extract rotational spectra., Comment: 32 pages, 15 figures

Published
2004
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11. Cluster structures within Fermionic Molecular Dynamics

Author

Neff, T. and Feldmeier, H.

Subjects
Nuclear Theory
Abstract

The many-body states in an extended Fermionic Molecular Dynamics approach are flexible enough to allow the description of nuclei with shell model nature as well as nuclei with cluster and halo structures. Different many-body configurations are obtained by minimizing the energy under constraints on collective variables like radius, dipole, quadrupole and octupole deformations. In the sense of the Generator Coordinate Method we perform variation after projection and multiconfiguration calculations. The same effective interaction derived from realistic interactions by means of the Unitary Correlation Operator Method is used for all nuclei. Aspects of the shell model and cluster nature of the ground and excited states of C12 are discussed. To understand energies and radii of neutron-rich He isotopes the soft-dipole mode is found to be important., Comment: 5 pages, proceedings of the 8th International conference on Clustering Aspects of Nuclear Structure and Dynamics, Nov. 2003, Nara, Japan, to be published in Nucl. Phys. A

Published
2003
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12. Realistic Interactions and Configuration Mixing in Fermionic Molecular Dynamics

Author

Neff, T., Feldmeier, H., Roth, R., and Schnack, J.

Subjects
Nuclear Theory
Abstract

In Fermionic Molecular Dynamics the occurrence of multifragmentation depends strongly on the intrinsic structure of the many-body state. Slater determinants with narrow single-particle states and a cluster substructure show multifragmentation in heavy-ion collisions while those with broad wave functions, which resemble more a shell-model picture, deexcite by particle emission. Which of the two type of states occurs as the ground state minimum or as a local minimum in the energy depends on the effective interaction. Both may equally well reproduce binding energy and radii of nuclei. This ambiguity led us to reinvestigate the derivation of the effective interaction from realistic nucleon-nucleon potentials by means of a unitary correlation operator which is much more suited for dynamical calculations than the G-matrix or the Jastrow method. First results of mixing many Slater determinants are also presented., Comment: 10 pages, 5 figures, Proc. of the International Workshop XXVII on Gross Properties of Nuclei and Nuclear Excitations, Hirschegg, Austria, January 17-23, 1999

Published
1999

13. Fermionic Molecular Dynamics and short range correlations

Author

Feldmeier, H., Neff, T., Roth, R., and Schnack, J.

Subjects
Nuclear Theory
Abstract

Fermionic Molecular Dynamics (FMD) models a system of fermions by means of many-body states which are composed of antisymmetrized products of single-particle states. These consist of one or several Gaussians localized in coordinate and momentum space. The parameters specifying them are the dynamical variables of the model. As the repulsive core of the nucleon-nucleon interaction induces short range correlations which cannot be accommodated by a Slater determinant, a novel approach, the unitary correlation operator method (UCOM), is applied. The unitary correlator moves two particles away from each other whenever their relative distance is within the repulsive core. The time-dependent variational principle yields the equations of motion for the variables. Energies of the stationary ground states are calculated and compared to exact many-body results for nuclei up to Ca 48. Time-dependent solutions are shown for collisions between nuclei., Comment: 8 pages, 4 figures, postscript 840 kB

Published
1998

14. A unitary correlation operator method

Author

Feldmeier, H., Neff, T., Roth, R., and Schnack, J.

Subjects
Nuclear Theory
Abstract

The short range repulsion between nucleons is treated by a unitary correlation operator which shifts the nucleons away from each other whenever their uncorrelated positions are within the replusive core. By formulating the correlation as a transformation of the relative distance between particle pairs, general analytic expressions for the correlated wave functions and correlated operators are given. The decomposition of correlated operators into irreducible n-body operators is discussed. The one- and two-body-irreducible parts are worked out explicitly and the contribution of three-body correlations is estimated to check convergence. Ground state energies of nuclei up to mass number A=48 are calculated with a spin-isospin-dependent potential and single Slater determinants as uncorrelated states. They show that the deduced energy- and mass-number-independent correlated two-body Hamiltonian reproduces all "exact" many-body calculations surprisingly well., Comment: 43 pages, several postscript figures, uses 'epsfig.cls'. Submitted to Nucl. Phys. A. More information available at http://www.gsi.de/~fmd

Published
1997
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15. Implications of early respiratory support strategies on disease progression in critical COVID-19: a matched subanalysis of the prospective RISC-19-ICU cohort

Author

Wendel Garcia, P, Aguirre-Bermeo, H, Buehler, P, Alfaro-Farias, M, Yuen, B, David, S, Tschoellitsch, T, Wengenmayer, T, Korsos, A, Fogagnolo, A, Kleger, G, Wu, M, Colombo, R, Turrini, F, Potalivo, A, Rezoagli, E, Rodriguez-Garcia, R, Castro, P, Lander-Azcona, A, Martin-Delgado, M, Lozano-Gomez, H, Ensner, R, Michot, M, Gehring, N, Schott, P, Siegemund, M, Merki, L, Wiegand, J, Jeitziner, M, Laube, M, Salomon, P, Hillgaertner, F, Dullenkopf, A, Ksouri, H, Cereghetti, S, Grazioli, S, Burkle, C, Marrel, J, Fleisch, I, Perez, M, Baltussen Weber, A, Ceruti, S, Marquardt, K, Hubner, T, Redecker, H, Studhalter, M, Stephan, M, Selz, D, Pietsch, U, Ristic, A, Heise, A, Meyer zu Bentrup, F, Franchitti Laurent, M, Fodor, P, Gaspert, T, Haberthuer, C, Colak, E, Heuberger, D, Fumeaux, T, Montomoli, J, Guerci, P, Schuepbach, R, Hilty, M, Roche-Campo, F, Algaba-Calderon, A, Apolo, J, Aslanidis, T, Babik, B, Boroli, F, Brem, J, Brenni, M, Brugger, S, Camen, G, Catena, E, Ceriani, R, Chau, I, Christ, A, Cogliati, C, Concha, P, Delahaye, G, Drvaric, I, Escos-Orta, J, Fabbri, S, Facondini, F, Filipovic, M, Gamez-Zapata, J, Gerecke, P, Gommers, D, Hillermann, T, Ince, C, Jenni-Moser, B, Jovic, M, Jurkolow, G, Klarer, A, Lambert, A, Laurent, J, Lavanchy, J, Lienhardt-Nobbe, B, Locher, P, Losser, M, Lussman, R, Magliocca, A, Margarit, A, Martinez, A, Mauri, R, Mayor-Vazquez, E, Meier, J, Moret-Bochatay, M, Murrone, M, Naon, D, Neff, T, Novy, E, Petersen, L, Pugin, J, Ramelet, A, Rilinger, J, Rimensberger, P, Sepulcri, M, Shaikh, K, Sieber, M, Simonini, M, Spadaro, S, Sridharan, G, Stahl, K, Staudacher, D, Taboada-Fraga, X, Tellez, A, Urech, S, Vitale, G, Vizmanos-Lamotte, G, Welte, T, Zalba-Etayo, B, Zellweger, N, Wendel Garcia P. D., Aguirre-Bermeo H., Buehler P. K., Alfaro-Farias M., Yuen B., David S., Tschoellitsch T., Wengenmayer T., Korsos A., Fogagnolo A., Kleger G. -R., Wu M. A., Colombo R., Turrini F., Potalivo A., Rezoagli E., Rodriguez-Garcia R., Castro P., Lander-Azcona A., Martin-Delgado M. C., Lozano-Gomez H., Ensner R., Michot M. P., Gehring N., Schott P., Siegemund M., Merki L., Wiegand J., Jeitziner M. M., Laube M., Salomon P., Hillgaertner F., Dullenkopf A., Ksouri H., Cereghetti S., Grazioli S., Burkle C., Marrel J., Fleisch I., Perez M. -H., Baltussen Weber A., Ceruti S., Marquardt K., Hubner T., Redecker H., Studhalter M., Stephan M., Selz D., Pietsch U., Ristic A., Heise A., Meyer zu Bentrup F., Franchitti Laurent M., Fodor P., Gaspert T., Haberthuer C., Colak E., Heuberger D. M., Fumeaux T., Montomoli J., Guerci P., Schuepbach R. A., Hilty M. P., Roche-Campo F., Algaba-Calderon A., Apolo J., Aslanidis T., Babik B., Boroli F., Brem J., Brenni M., Brugger S. D., Camen G., Catena E., Ceriani R., Chau I., Christ A., Cogliati C., Concha P., Delahaye G., Drvaric I., Escos-Orta J., Fabbri S., Facondini F., Filipovic M., Gamez-Zapata J., Gerecke P., Gommers D., Hillermann T., Ince C., Jenni-Moser B., Jovic M., Jurkolow G., Klarer A., Lambert A., Laurent J. -C., Lavanchy J., Lienhardt-Nobbe B., Locher P., Losser M. -R., Lussman R. F., Magliocca A., Margarit A., Martinez A., Mauri R., Mayor-Vazquez E., Meier J., Moret-Bochatay M., Murrone M., Naon D., Neff T., Novy E., Petersen L., Pugin J., Ramelet A. -S., Rilinger J., Rimensberger P. C., Sepulcri M., Shaikh K., Sieber M., Simonini M. S., Spadaro S., Sridharan G. O., Stahl K., Staudacher D. L., Taboada-Fraga X., Tellez A., Urech S., Vitale G., Vizmanos-Lamotte G., Welte T., Zalba-Etayo B., Zellweger N., Wendel Garcia, P, Aguirre-Bermeo, H, Buehler, P, Alfaro-Farias, M, Yuen, B, David, S, Tschoellitsch, T, Wengenmayer, T, Korsos, A, Fogagnolo, A, Kleger, G, Wu, M, Colombo, R, Turrini, F, Potalivo, A, Rezoagli, E, Rodriguez-Garcia, R, Castro, P, Lander-Azcona, A, Martin-Delgado, M, Lozano-Gomez, H, Ensner, R, Michot, M, Gehring, N, Schott, P, Siegemund, M, Merki, L, Wiegand, J, Jeitziner, M, Laube, M, Salomon, P, Hillgaertner, F, Dullenkopf, A, Ksouri, H, Cereghetti, S, Grazioli, S, Burkle, C, Marrel, J, Fleisch, I, Perez, M, Baltussen Weber, A, Ceruti, S, Marquardt, K, Hubner, T, Redecker, H, Studhalter, M, Stephan, M, Selz, D, Pietsch, U, Ristic, A, Heise, A, Meyer zu Bentrup, F, Franchitti Laurent, M, Fodor, P, Gaspert, T, Haberthuer, C, Colak, E, Heuberger, D, Fumeaux, T, Montomoli, J, Guerci, P, Schuepbach, R, Hilty, M, Roche-Campo, F, Algaba-Calderon, A, Apolo, J, Aslanidis, T, Babik, B, Boroli, F, Brem, J, Brenni, M, Brugger, S, Camen, G, Catena, E, Ceriani, R, Chau, I, Christ, A, Cogliati, C, Concha, P, Delahaye, G, Drvaric, I, Escos-Orta, J, Fabbri, S, Facondini, F, Filipovic, M, Gamez-Zapata, J, Gerecke, P, Gommers, D, Hillermann, T, Ince, C, Jenni-Moser, B, Jovic, M, Jurkolow, G, Klarer, A, Lambert, A, Laurent, J, Lavanchy, J, Lienhardt-Nobbe, B, Locher, P, Losser, M, Lussman, R, Magliocca, A, Margarit, A, Martinez, A, Mauri, R, Mayor-Vazquez, E, Meier, J, Moret-Bochatay, M, Murrone, M, Naon, D, Neff, T, Novy, E, Petersen, L, Pugin, J, Ramelet, A, Rilinger, J, Rimensberger, P, Sepulcri, M, Shaikh, K, Sieber, M, Simonini, M, Spadaro, S, Sridharan, G, Stahl, K, Staudacher, D, Taboada-Fraga, X, Tellez, A, Urech, S, Vitale, G, Vizmanos-Lamotte, G, Welte, T, Zalba-Etayo, B, Zellweger, N, Wendel Garcia P. D., Aguirre-Bermeo H., Buehler P. K., Alfaro-Farias M., Yuen B., David S., Tschoellitsch T., Wengenmayer T., Korsos A., Fogagnolo A., Kleger G. -R., Wu M. A., Colombo R., Turrini F., Potalivo A., Rezoagli E., Rodriguez-Garcia R., Castro P., Lander-Azcona A., Martin-Delgado M. C., Lozano-Gomez H., Ensner R., Michot M. P., Gehring N., Schott P., Siegemund M., Merki L., Wiegand J., Jeitziner M. M., Laube M., Salomon P., Hillgaertner F., Dullenkopf A., Ksouri H., Cereghetti S., Grazioli S., Burkle C., Marrel J., Fleisch I., Perez M. -H., Baltussen Weber A., Ceruti S., Marquardt K., Hubner T., Redecker H., Studhalter M., Stephan M., Selz D., Pietsch U., Ristic A., Heise A., Meyer zu Bentrup F., Franchitti Laurent M., Fodor P., Gaspert T., Haberthuer C., Colak E., Heuberger D. M., Fumeaux T., Montomoli J., Guerci P., Schuepbach R. A., Hilty M. P., Roche-Campo F., Algaba-Calderon A., Apolo J., Aslanidis T., Babik B., Boroli F., Brem J., Brenni M., Brugger S. D., Camen G., Catena E., Ceriani R., Chau I., Christ A., Cogliati C., Concha P., Delahaye G., Drvaric I., Escos-Orta J., Fabbri S., Facondini F., Filipovic M., Gamez-Zapata J., Gerecke P., Gommers D., Hillermann T., Ince C., Jenni-Moser B., Jovic M., Jurkolow G., Klarer A., Lambert A., Laurent J. -C., Lavanchy J., Lienhardt-Nobbe B., Locher P., Losser M. -R., Lussman R. F., Magliocca A., Margarit A., Martinez A., Mauri R., Mayor-Vazquez E., Meier J., Moret-Bochatay M., Murrone M., Naon D., Neff T., Novy E., Petersen L., Pugin J., Ramelet A. -S., Rilinger J., Rimensberger P. C., Sepulcri M., Shaikh K., Sieber M., Simonini M. S., Spadaro S., Sridharan G. O., Stahl K., Staudacher D. L., Taboada-Fraga X., Tellez A., Urech S., Vitale G., Vizmanos-Lamotte G., Welte T., Zalba-Etayo B., and Zellweger N.

Abstract

Background: Uncertainty about the optimal respiratory support strategies in critically ill COVID-19 patients is widespread. While the risks and benefits of noninvasive techniques versus early invasive mechanical ventilation (IMV) are intensely debated, actual evidence is lacking. We sought to assess the risks and benefits of different respiratory support strategies, employed in intensive care units during the first months of the COVID-19 pandemic on intubation and intensive care unit (ICU) mortality rates. Methods: Subanalysis of a prospective, multinational registry of critically ill COVID-19 patients. Patients were subclassified into standard oxygen therapy ≥10 L/min (SOT), high-flow oxygen therapy (HFNC), noninvasive positive-pressure ventilation (NIV), and early IMV, according to the respiratory support strategy employed at the day of admission to ICU. Propensity score matching was performed to ensure comparability between groups. Results: Initially, 1421 patients were assessed for possible study inclusion. Of these, 351 patients (85 SOT, 87 HFNC, 87 NIV, and 92 IMV) remained eligible for full analysis after propensity score matching. 55% of patients initially receiving noninvasive respiratory support required IMV. The intubation rate was lower in patients initially ventilated with HFNC and NIV compared to those who received SOT (SOT: 64%, HFNC: 52%, NIV: 49%, p = 0.025). Compared to the other respiratory support strategies, NIV was associated with a higher overall ICU mortality (SOT: 18%, HFNC: 20%, NIV: 37%, IMV: 25%, p = 0.016). Conclusion: In this cohort of critically ill patients with COVID-19, a trial of HFNC appeared to be the most balanced initial respiratory support strategy, given the reduced intubation rate and comparable ICU mortality rate. Nonetheless, considering the uncertainty and stress associated with the COVID-19 pandemic, SOT and early IMV represented safe initial respiratory support strategies. The presented findings, in

Published
2021

16. Machine learning using the extreme gradient boosting (XGBoost) algorithm predicts 5-day delta of SOFA score at ICU admission in COVID-19 patients

Author

Montomoli, J, Romeo, L, Moccia, S, Bernardini, M, Migliorelli, L, Berardini, D, Donati, A, Carsetti, A, Bocci, M, Wendel Garcia, P, Fumeaux, T, Guerci, P, Schupbach, R, Ince, C, Frontoni, E, Hilty, M, Alfaro-Farias, M, Vizmanos-Lamotte, G, Tschoellitsch, T, Meier, J, Aguirre-Bermeo, H, Apolo, J, Martinez, A, Jurkolow, G, Delahaye, G, Novy, E, Losser, M, Wengenmayer, T, Rilinger, J, Staudacher, D, David, S, Welte, T, Stahl, K, Pavlos, A, Aslanidis, T, Korsos, A, Babik, B, Nikandish, R, Rezoagli, E, Giacomini, M, Nova, A, Fogagnolo, A, Spadaro, S, Ceriani, R, Murrone, M, Wu, M, Cogliati, C, Colombo, R, Catena, E, Turrini, F, Simonini, M, Fabbri, S, Potalivo, A, Facondini, F, Gangitano, G, Perin, T, Grazia Bocci, M, Antonelli, M, Gommers, D, Rodriguez-Garcia, R, Gamez-Zapata, J, Taboada-Fraga, X, Castro, P, Tellez, A, Lander-Azcona, A, Escos-Orta, J, Martin-Delgado, M, Algaba-Calderon, A, Franch-Llasat, D, Roche-Campo, F, Lozano-Gomez, H, Zalba-Etayo, B, Michot, M, Klarer, A, Ensner, R, Schott, P, Urech, S, Zellweger, N, Merki, L, Lambert, A, Laube, M, Jeitziner, M, Jenni-Moser, B, Wiegand, J, Yuen, B, Lienhardt-Nobbe, B, Westphalen, A, Salomon, P, Drvaric, I, Hillgaertner, F, Sieber, M, Dullenkopf, A, Petersen, L, Chau, I, Ksouri, H, Sridharan, G, Cereghetti, S, Boroli, F, Pugin, J, Grazioli, S, Rimensberger, P, Burkle, C, Marrel, J, Brenni, M, Fleisch, I, Lavanchy, J, Perez, M, Ramelet, A, Weber, A, Gerecke, P, Christ, A, Ceruti, S, Glotta, A, Marquardt, K, Shaikh, K, Hubner, T, Neff, T, Redecker, H, Moret-Bochatay, M, Bentrup, F, Studhalter, M, Stephan, M, Brem, J, Gehring, N, Selz, D, Naon, D, Kleger, G, Pietsch, U, Filipovic, M, Ristic, A, Sepulcri, M, Heise, A, Franchitti Laurent, M, Laurent, J, Schuepbach, R, Heuberger, D, Buhler, P, Brugger, S, Fodor, P, Locher, P, Camen, G, Gaspert, T, Jovic, M, Haberthuer, C, Lussman, R, Colak, E, Montomoli J., Romeo L., Moccia S., Bernardini M., Migliorelli L., Berardini D., Donati A., Carsetti A., Bocci M. G., Wendel Garcia P. D., Fumeaux T., Guerci P., Schupbach R. A., Ince C., Frontoni E., Hilty M. P., Alfaro-Farias M., Vizmanos-Lamotte G., Tschoellitsch T., Meier J., Aguirre-Bermeo H., Apolo J., Martinez A., Jurkolow G., Delahaye G., Novy E., Losser M. -R., Wengenmayer T., Rilinger J., Staudacher D. L., David S., Welte T., Stahl K., Pavlos A., Aslanidis T., Korsos A., Babik B., Nikandish R., Rezoagli E., Giacomini M., Nova A., Fogagnolo A., Spadaro S., Ceriani R., Murrone M., Wu M. A., Cogliati C., Colombo R., Catena E., Turrini F., Simonini M. S., Fabbri S., Potalivo A., Facondini F., Gangitano G., Perin T., Grazia Bocci M., Antonelli M., Gommers D., Rodriguez-Garcia R., Gamez-Zapata J., Taboada-Fraga X., Castro P., Tellez A., Lander-Azcona A., Escos-Orta J., Martin-Delgado M. C., Algaba-Calderon A., Franch-Llasat D., Roche-Campo F., Lozano-Gomez H., Zalba-Etayo B., Michot M. P., Klarer A., Ensner R., Schott P., Urech S., Zellweger N., Merki L., Lambert A., Laube M., Jeitziner M. M., Jenni-Moser B., Wiegand J., Yuen B., Lienhardt-Nobbe B., Westphalen A., Salomon P., Drvaric I., Hillgaertner F., Sieber M., Dullenkopf A., Petersen L., Chau I., Ksouri H., Sridharan G. O., Cereghetti S., Boroli F., Pugin J., Grazioli S., Rimensberger P. C., Burkle C., Marrel J., Brenni M., Fleisch I., Lavanchy J., Perez M. -H., Ramelet A. -S., Weber A. B., Gerecke P., Christ A., Ceruti S., Glotta A., Marquardt K., Shaikh K., Hubner T., Neff T., Redecker H., Moret-Bochatay M., Bentrup F. Z., Studhalter M., Stephan M., Brem J., Gehring N., Selz D., Naon D., Kleger G. -R., Pietsch U., Filipovic M., Ristic A., Sepulcri M., Heise A., Franchitti Laurent M., Laurent J. -C., Schuepbach R., Heuberger D., Buhler P., Brugger S., Fodor P., Locher P., Camen G., Gaspert T., Jovic M., Haberthuer C., Lussman R. F., Colak E., Montomoli, J, Romeo, L, Moccia, S, Bernardini, M, Migliorelli, L, Berardini, D, Donati, A, Carsetti, A, Bocci, M, Wendel Garcia, P, Fumeaux, T, Guerci, P, Schupbach, R, Ince, C, Frontoni, E, Hilty, M, Alfaro-Farias, M, Vizmanos-Lamotte, G, Tschoellitsch, T, Meier, J, Aguirre-Bermeo, H, Apolo, J, Martinez, A, Jurkolow, G, Delahaye, G, Novy, E, Losser, M, Wengenmayer, T, Rilinger, J, Staudacher, D, David, S, Welte, T, Stahl, K, Pavlos, A, Aslanidis, T, Korsos, A, Babik, B, Nikandish, R, Rezoagli, E, Giacomini, M, Nova, A, Fogagnolo, A, Spadaro, S, Ceriani, R, Murrone, M, Wu, M, Cogliati, C, Colombo, R, Catena, E, Turrini, F, Simonini, M, Fabbri, S, Potalivo, A, Facondini, F, Gangitano, G, Perin, T, Grazia Bocci, M, Antonelli, M, Gommers, D, Rodriguez-Garcia, R, Gamez-Zapata, J, Taboada-Fraga, X, Castro, P, Tellez, A, Lander-Azcona, A, Escos-Orta, J, Martin-Delgado, M, Algaba-Calderon, A, Franch-Llasat, D, Roche-Campo, F, Lozano-Gomez, H, Zalba-Etayo, B, Michot, M, Klarer, A, Ensner, R, Schott, P, Urech, S, Zellweger, N, Merki, L, Lambert, A, Laube, M, Jeitziner, M, Jenni-Moser, B, Wiegand, J, Yuen, B, Lienhardt-Nobbe, B, Westphalen, A, Salomon, P, Drvaric, I, Hillgaertner, F, Sieber, M, Dullenkopf, A, Petersen, L, Chau, I, Ksouri, H, Sridharan, G, Cereghetti, S, Boroli, F, Pugin, J, Grazioli, S, Rimensberger, P, Burkle, C, Marrel, J, Brenni, M, Fleisch, I, Lavanchy, J, Perez, M, Ramelet, A, Weber, A, Gerecke, P, Christ, A, Ceruti, S, Glotta, A, Marquardt, K, Shaikh, K, Hubner, T, Neff, T, Redecker, H, Moret-Bochatay, M, Bentrup, F, Studhalter, M, Stephan, M, Brem, J, Gehring, N, Selz, D, Naon, D, Kleger, G, Pietsch, U, Filipovic, M, Ristic, A, Sepulcri, M, Heise, A, Franchitti Laurent, M, Laurent, J, Schuepbach, R, Heuberger, D, Buhler, P, Brugger, S, Fodor, P, Locher, P, Camen, G, Gaspert, T, Jovic, M, Haberthuer, C, Lussman, R, Colak, E, Montomoli J., Romeo L., Moccia S., Bernardini M., Migliorelli L., Berardini D., Donati A., Carsetti A., Bocci M. G., Wendel Garcia P. D., Fumeaux T., Guerci P., Schupbach R. A., Ince C., Frontoni E., Hilty M. P., Alfaro-Farias M., Vizmanos-Lamotte G., Tschoellitsch T., Meier J., Aguirre-Bermeo H., Apolo J., Martinez A., Jurkolow G., Delahaye G., Novy E., Losser M. -R., Wengenmayer T., Rilinger J., Staudacher D. L., David S., Welte T., Stahl K., Pavlos A., Aslanidis T., Korsos A., Babik B., Nikandish R., Rezoagli E., Giacomini M., Nova A., Fogagnolo A., Spadaro S., Ceriani R., Murrone M., Wu M. A., Cogliati C., Colombo R., Catena E., Turrini F., Simonini M. S., Fabbri S., Potalivo A., Facondini F., Gangitano G., Perin T., Grazia Bocci M., Antonelli M., Gommers D., Rodriguez-Garcia R., Gamez-Zapata J., Taboada-Fraga X., Castro P., Tellez A., Lander-Azcona A., Escos-Orta J., Martin-Delgado M. C., Algaba-Calderon A., Franch-Llasat D., Roche-Campo F., Lozano-Gomez H., Zalba-Etayo B., Michot M. P., Klarer A., Ensner R., Schott P., Urech S., Zellweger N., Merki L., Lambert A., Laube M., Jeitziner M. M., Jenni-Moser B., Wiegand J., Yuen B., Lienhardt-Nobbe B., Westphalen A., Salomon P., Drvaric I., Hillgaertner F., Sieber M., Dullenkopf A., Petersen L., Chau I., Ksouri H., Sridharan G. O., Cereghetti S., Boroli F., Pugin J., Grazioli S., Rimensberger P. C., Burkle C., Marrel J., Brenni M., Fleisch I., Lavanchy J., Perez M. -H., Ramelet A. -S., Weber A. B., Gerecke P., Christ A., Ceruti S., Glotta A., Marquardt K., Shaikh K., Hubner T., Neff T., Redecker H., Moret-Bochatay M., Bentrup F. Z., Studhalter M., Stephan M., Brem J., Gehring N., Selz D., Naon D., Kleger G. -R., Pietsch U., Filipovic M., Ristic A., Sepulcri M., Heise A., Franchitti Laurent M., Laurent J. -C., Schuepbach R., Heuberger D., Buhler P., Brugger S., Fodor P., Locher P., Camen G., Gaspert T., Jovic M., Haberthuer C., Lussman R. F., and Colak E.

Abstract

Background: Accurate risk stratification of critically ill patients with coronavirus disease 2019 (COVID-19) is essential for optimizing resource allocation, delivering targeted interventions, and maximizing patient survival probability. Machine learning (ML) techniques are attracting increased interest for the development of prediction models as they excel in the analysis of complex signals in data-rich environments such as critical care. Methods: We retrieved data on patients with COVID-19 admitted to an intensive care unit (ICU) between March and October 2020 from the RIsk Stratification in COVID-19 patients in the Intensive Care Unit (RISC-19-ICU) registry. We applied the Extreme Gradient Boosting (XGBoost) algorithm to the data to predict as a binary outcome the increase or decrease in patients’ Sequential Organ Failure Assessment (SOFA) score on day 5 after ICU admission. The model was iteratively cross-validated in different subsets of the study cohort. Results: The final study population consisted of 675 patients. The XGBoost model correctly predicted a decrease in SOFA score in 320/385 (83%) critically ill COVID-19 patients, and an increase in the score in 210/290 (72%) patients. The area under the mean receiver operating characteristic curve for XGBoost was significantly higher than that for the logistic regression model (0.86 vs. 0.69, P < 0.01 [paired t-test with 95% confidence interval]). Conclusions: The XGBoost model predicted the change in SOFA score in critically ill COVID-19 patients admitted to the ICU and can guide clinical decision support systems (CDSSs) aimed at optimizing available resources.

Published
2021

19. Implications of early respiratory support strategies on disease progression in critical COVID-19: a matched subanalysis of the prospective RISC-19-ICU cohort

Author

Wendel Garcia P. D., Aguirre-Bermeo H., Buehler P. K., Alfaro-Farias M., Yuen B., David S., Tschoellitsch T., Wengenmayer T., Korsos A., Fogagnolo A., Kleger G. -R., Wu M. A., Colombo R., Turrini F., Potalivo A., Rezoagli E., Rodriguez-Garcia R., Castro P., Lander-Azcona A., Martin-Delgado M. C., Lozano-Gomez H., Ensner R., Michot M. P., Gehring N., Schott P., Siegemund M., Merki L., Wiegand J., Jeitziner M. M., Laube M., Salomon P., Hillgaertner F., Dullenkopf A., Ksouri H., Cereghetti S., Grazioli S., Burkle C., Marrel J., Fleisch I., Perez M. -H., Baltussen Weber A., Ceruti S., Marquardt K., Hubner T., Redecker H., Studhalter M., Stephan M., Selz D., Pietsch U., Ristic A., Heise A., Meyer zu Bentrup F., Franchitti Laurent M., Fodor P., Gaspert T., Haberthuer C., Colak E., Heuberger D. M., Fumeaux T., Montomoli J., Guerci P., Schuepbach R. A., Hilty M. P., Roche-Campo F., Algaba-Calderon A., Apolo J., Aslanidis T., Babik B., Boroli F., Brem J., Brenni M., Brugger S. D., Camen G., Catena E., Ceriani R., Chau I., Christ A., Cogliati C., Concha P., Delahaye G., Drvaric I., Escos-Orta J., Fabbri S., Facondini F., Filipovic M., Gamez-Zapata J., Gerecke P., Gommers D., Hillermann T., Ince C., Jenni-Moser B., Jovic M., Jurkolow G., Klarer A., Lambert A., Laurent J. -C., Lavanchy J., Lienhardt-Nobbe B., Locher P., Losser M. -R., Lussman R. F., Magliocca A., Margarit A., Martinez A., Mauri R., Mayor-Vazquez E., Meier J., Moret-Bochatay M., Murrone M., Naon D., Neff T., Novy E., Petersen L., Pugin J., Ramelet A. -S., Rilinger J., Rimensberger P. C., Sepulcri M., Shaikh K., Sieber M., Simonini M. S., Spadaro S., Sridharan G. O., Stahl K., Staudacher D. L., Taboada-Fraga X., Tellez A., Urech S., Vitale G., Vizmanos-Lamotte G., Welte T., Zalba-Etayo B., Zellweger N., Graduate School, ACS - Atherosclerosis & ischemic syndromes, ACS - Microcirculation, AII - Inflammatory diseases, RISC-19-ICU Investigators, Wendel Garcia, P.D., Aguirre-Bermeo, H., Buehler, P.K., Alfaro-Farias, M., Yuen, B., David, S., Tschoellitsch, T., Wengenmayer, T., Korsos, A., Fogagnolo, A., Kleger, G.R., Wu, M.A., Colombo, R., Turrini, F., Potalivo, A., Rezoagli, E., Rodríguez-García, R., Castro, P., Lander-Azcona, A., Martín-Delgado, M.C., Lozano-Gómez, H., Ensner, R., Michot, M.P., Gehring, N., Schott, P., Siegemund, M., Merki, L., Wiegand, J., Jeitziner, M.M., Laube, M., Salomon, P., Hillgaertner, F., Dullenkopf, A., Ksouri, H., Cereghetti, S., Grazioli, S., Bürkle, C., Marrel, J., Fleisch, I., Perez, M.H., Baltussen Weber, A., Ceruti, S., Marquardt, K., Hübner, T., Redecker, H., Studhalter, M., Stephan, M., Selz, D., Pietsch, U., Ristic, A., Heise, A., Meyer Zu Bentrup, F., Franchitti Laurent, M., Fodor, P., Gaspert, T., Haberthuer, C., Colak, E., Heuberger, D.M., Fumeaux, T., Montomoli, J., Guerci, P., Schuepbach, R.A., Hilty, M.P., Roche-Campo, F., Algaba-Calderon, A., Apolo, J., Aslanidis, T., Babik, B., Boroli, F., Brem, J., Brenni, M., Brugger, S.D., Camen, G., Catena, E., Ceriani, R., Chau, I., Christ, A., Cogliati, C., Concha, P., Delahaye, G., Drvaric, I., Escós-Orta, J., Fabbri, S., Facondini, F., Filipovic, M., Gámez-Zapata, J., Gerecke, P., Gommers, D., Hillermann, T., Ince, C., Jenni-Moser, B., Jovic, M., Jurkolow, G., Klarer, A., Lambert, A., Laurent, J.C., Lavanchy, J., Lienhardt-Nobbe, B., Locher, P., Losser, M.R., Lussman, R.F., Magliocca, A., Margarit, A., Martínez, A., Mauri, R., Mayor-Vázquez, E., Meier, J., Moret-Bochatay, M., Murrone, M., Naon, D., Neff, T., Novy, E., Petersen, L., Pugin, J., Ramelet, A.S., Rilinger, J., Rimensberger, P.C., Sepulcri, M., Shaikh, K., Sieber, M., Simonini, M.S., Spadaro, S., Sridharan, G.O., Stahl, K., Staudacher, D.L., Taboada-Fraga, X., Tellez, A., Urech, S., Vitale, G., Vizmanos-Lamotte, G., Welte, T., Zalba-Etayo, B., Zellweger, N., Wendel Garcia, P, Aguirre-Bermeo, H, Buehler, P, Alfaro-Farias, M, Yuen, B, David, S, Tschoellitsch, T, Wengenmayer, T, Korsos, A, Fogagnolo, A, Kleger, G, Wu, M, Colombo, R, Turrini, F, Potalivo, A, Rezoagli, E, Rodriguez-Garcia, R, Castro, P, Lander-Azcona, A, Martin-Delgado, M, Lozano-Gomez, H, Ensner, R, Michot, M, Gehring, N, Schott, P, Siegemund, M, Merki, L, Wiegand, J, Jeitziner, M, Laube, M, Salomon, P, Hillgaertner, F, Dullenkopf, A, Ksouri, H, Cereghetti, S, Grazioli, S, Burkle, C, Marrel, J, Fleisch, I, Perez, M, Baltussen Weber, A, Ceruti, S, Marquardt, K, Hubner, T, Redecker, H, Studhalter, M, Stephan, M, Selz, D, Pietsch, U, Ristic, A, Heise, A, Meyer zu Bentrup, F, Franchitti Laurent, M, Fodor, P, Gaspert, T, Haberthuer, C, Colak, E, Heuberger, D, Fumeaux, T, Montomoli, J, Guerci, P, Schuepbach, R, Hilty, M, Roche-Campo, F, Algaba-Calderon, A, Apolo, J, Aslanidis, T, Babik, B, Boroli, F, Brem, J, Brenni, M, Brugger, S, Camen, G, Catena, E, Ceriani, R, Chau, I, Christ, A, Cogliati, C, Concha, P, Delahaye, G, Drvaric, I, Escos-Orta, J, Fabbri, S, Facondini, F, Filipovic, M, Gamez-Zapata, J, Gerecke, P, Gommers, D, Hillermann, T, Ince, C, Jenni-Moser, B, Jovic, M, Jurkolow, G, Klarer, A, Lambert, A, Laurent, J, Lavanchy, J, Lienhardt-Nobbe, B, Locher, P, Losser, M, Lussman, R, Magliocca, A, Margarit, A, Martinez, A, Mauri, R, Mayor-Vazquez, E, Meier, J, Moret-Bochatay, M, Murrone, M, Naon, D, Neff, T, Novy, E, Petersen, L, Pugin, J, Ramelet, A, Rilinger, J, Rimensberger, P, Sepulcri, M, Shaikh, K, Sieber, M, Simonini, M, Spadaro, S, Sridharan, G, Stahl, K, Staudacher, D, Taboada-Fraga, X, Tellez, A, Urech, S, Vitale, G, Vizmanos-Lamotte, G, Welte, T, Zalba-Etayo, B, Zellweger, N, and Intensive Care

Subjects
Male, ARDS, Time Factors, medicine.medical_treatment, Old age, Critical Care and Intensive Care Medicine, law.invention, 0302 clinical medicine, law, Oxygen therapy, Noninvasive mechanical ventilation, Intubation, 030212 general & internal medicine, Hospital Mortality, Prospective Studies, Registries, Prospective cohort study, 610 Medicine & health, Unitats de cures intensives, Intensive care units, Medical emergencies. Critical care. Intensive care. First aid, Middle Aged, Intensive care unit, Intensive Care Units, Treatment Outcome, Vellesa, High flow oxygen therapy, Disease Progression, Female, Standard oxygen therapy, medicine.medical_specialty, Respiratory Therapy, Critical Illness, NO, 03 medical and health sciences, Intensive care, medicine, Humans, Invasive mechanical ventilation, Critically ill, Patient self-inflicted lung injury, Aged, Retrospective Studies, Mechanical ventilation, COVID-19/mortality, COVID-19/therapy, Critical Illness/mortality, Critical Illness/therapy, Respiratory Therapy/methods, Respiratory Therapy/statistics & numerical data, COVID-19, Respiratory support, business.industry, RC86-88.9, Research, Retrospective cohort study, medicine.disease, Malalts en estat crític, 030228 respiratory system, Emergency medicine, business
Abstract

Background Uncertainty about the optimal respiratory support strategies in critically ill COVID-19 patients is widespread. While the risks and benefits of noninvasive techniques versus early invasive mechanical ventilation (IMV) are intensely debated, actual evidence is lacking. We sought to assess the risks and benefits of different respiratory support strategies, employed in intensive care units during the first months of the COVID-19 pandemic on intubation and intensive care unit (ICU) mortality rates. Methods Subanalysis of a prospective, multinational registry of critically ill COVID-19 patients. Patients were subclassified into standard oxygen therapy ≥10 L/min (SOT), high-flow oxygen therapy (HFNC), noninvasive positive-pressure ventilation (NIV), and early IMV, according to the respiratory support strategy employed at the day of admission to ICU. Propensity score matching was performed to ensure comparability between groups. Results Initially, 1421 patients were assessed for possible study inclusion. Of these, 351 patients (85 SOT, 87 HFNC, 87 NIV, and 92 IMV) remained eligible for full analysis after propensity score matching. 55% of patients initially receiving noninvasive respiratory support required IMV. The intubation rate was lower in patients initially ventilated with HFNC and NIV compared to those who received SOT (SOT: 64%, HFNC: 52%, NIV: 49%, p = 0.025). Compared to the other respiratory support strategies, NIV was associated with a higher overall ICU mortality (SOT: 18%, HFNC: 20%, NIV: 37%, IMV: 25%, p = 0.016). Conclusion In this cohort of critically ill patients with COVID-19, a trial of HFNC appeared to be the most balanced initial respiratory support strategy, given the reduced intubation rate and comparable ICU mortality rate. Nonetheless, considering the uncertainty and stress associated with the COVID-19 pandemic, SOT and early IMV represented safe initial respiratory support strategies. The presented findings, in agreement with classic ARDS literature, suggest that NIV should be avoided whenever possible due to the elevated ICU mortality risk.

Published
2021

23. Einzelteilüberwachung in Beschleunigungsphasen*/Single item processes containing acceleration phases – A comparison between conventional regression tools and machine learning

Author

B. Denkena, M. Witt, Neff. T., and B. Bergmann

Subjects
Acceleration, Control and Systems Engineering, business.industry, Computer science, Automotive Engineering, Artificial intelligence, business, Machine learning, computer.software_genre, Single item, computer, Regression
Abstract

Die modellbasierte Prozessüberwachung für die Einzelteilfertigung scheitert häufig an Prozessphasen, welche Beschleunigungsanteile enthalten. Der Beitrag widmet sich der Kompensation von Beschleunigungs- und Reibanteilen im Messsignal durch kennfeldbasierte Ansätze sowie Methoden des maschinellen Lernens. Für die anschließende Modellierung des Gesamtsignals zur Prozessüberwachung werden Regressionsansätze mit Methoden des maschinellen Lernens verglichen, welche sich als besonders geeignet zeigen. Model-based process monitoring often fails to adequately assess process segments that exhibit acceleration. This work evaluates different compensation approaches for non-process-specific parts of the measured signals. For a subsequent modelling of the complete input signal enabling the monitoring of single item processes, conventional regression models are compared to machine learning methods. The latter prove to be very well suited for these requirements.

Published
2019

28. Pamrevlumab, an anti-connective tissue growth factor therapy, for idiopathic pulmonary fibrosis (PRAISE): a phase 2, randomised, double-blind, placebo-controlled trial

Author

Richeldi, Luca, Fernandez Perez, E. R., Costabel, U., Albera, C., Lederer, D. J., Flaherty, K. R., Ettinger, N., Perez, R., Scholand, M. B., Goldin, J., Peony Yu, K. -H., Neff, T., Porter, S., Zhong, M., Gorina, E., Kouchakji, E., Raghu, G., Richeldi L. (ORCID:0000-0001-8594-1448), Richeldi, Luca, Fernandez Perez, E. R., Costabel, U., Albera, C., Lederer, D. J., Flaherty, K. R., Ettinger, N., Perez, R., Scholand, M. B., Goldin, J., Peony Yu, K. -H., Neff, T., Porter, S., Zhong, M., Gorina, E., Kouchakji, E., Raghu, G., and Richeldi L. (ORCID:0000-0001-8594-1448)

Abstract

Background: Connective tissue growth factor (CTGF) is a secreted glycoprotein that has a central role in the process of fibrosis. This study was designed to assess the safety, tolerability, and efficacy of pamrevlumab (FG-3019), a fully recombinant human monoclonal antibody against CTGF, in idiopathic pulmonary fibrosis. The aim was to establish whether pamrevlumab could slow, stop, or reverse progression of idiopathic pulmonary fibrosis. Methods: The phase 2, randomised, double-blind, placebo-controlled PRAISE trial was done at 39 medical centres in seven countries (Australia, Bulgaria, Canada, India, New Zealand, South Africa, and the USA). Patients with idiopathic pulmonary fibrosis and percentage of predicted forced vital capacity (FVC) of 55% or greater were enrolled and randomly assigned (1:1) by use of interactive responsive technology to intravenous infusion of pamrevlumab 30 mg/kg or placebo every 3 weeks over 48 weeks (16 infusions). The primary efficacy outcome was change from baseline in percentage of predicted FVC at week 48. Disease progression (defined as a decline from baseline in percentage of predicted FVC of ≥10%, or death) at week 48 was a key secondary efficacy outcome. All patients in the pamrevlumab group received at least one dose of the study drug and were analysed for safety. Two patients in the placebo group were excluded from the intention-to-treat population for the efficacy analyses because of enrolment error. This trial is registered with ClinicalTrials.gov, NCT01890265. Findings: Between Aug 17, 2013, and July 21, 2017, 103 patients were randomly assigned (50 to pamrevlumab and 53 to placebo). Pamrevlumab reduced the decline in percentage of predicted FVC by 60·3% at week 48 (mean change from baseline −2·9% with pamrevlumab vs −7·2% with placebo; between-group difference 4·3% [95% CI 0·4–8·3]; p=0·033). The proportion of patients with disease progression was lower in the pamrevlumab group than in the placebo group at week 48 (10·0% vs

Published
2020

43. Authentication methods for voice services on smart speakers – a multi-method study on perceived security and ease of use

Author

Renz Andreas, Neff Thomas, Baldauf Matthias, and Maier Edith

Subjects
conversational services, user authentication, voice assistant, Communication. Mass media, P87-96, Electronic computers. Computer science, QA75.5-76.95
Abstract

With the increasing proliferation of security-critical voice-based services such as voice banking, user authentication on smart speakers is becoming a vital requirement. Prior research on verifying the speaker’s identity has been taken a technical perspective predominantly, while respective user-centered research is scarce. To investigate authentication methods for smart speakers from a user’s perspective, we conducted a multi-method experiment. In a comprehensive online survey (n = 696) and a comparative lab study (n = 18) with an advanced functional prototype we studied 6 authentication methods (spoken PIN, biometrics, app with button/voice confirmation, card reader, sound authentication) regarding their perceived security and ease of use. While token-based authentication approaches (in particular an authenticator app on a smartphone) typically are perceived as more secure, they are found inferior when it comes to the ease of use. The currently most frequently used authentication method for smart speakers, the spoken PIN method, seems to represent a compromise between security and ease of use. The sophisticated sound authentication was appreciated for its ease of use, however, was rated worst regarding the perceived security.

Published
2023
Full Text
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44. Determination of the neutron-capture rate of C-17 for r-process nucleosynthesis

Author

Heine, M, Typel, S, Wu, M-R, Adachi, T, Aksyutina, Y, Alcantara, J, Altstadt, S, Alvarez-Pol, H, Ashwood, N, Atar, L, Aumann, T, Avdeichikov, V, Barr, M, Beceiro-Novo, S, Bemmerer, D, Benlliure, J, Bertulani, CA, Boretzky, K, Borge, MJG, Burgunder, G, Caamano, M, Caesar, C, Casarejos, E, Catford, W, Cederkaell, J, Chakraborty, S, Chartier, M, Chulkov, LV, Cortina-Gil, D, Crespo, R, Pramanik, U Datta, Fernandez, P Diaz, Dillmann, I, Elekes, Z, Enders, J, Ershova, O, Estrade, A, Farinon, F, Fraile, LM, Freer, M, Freudenberger, M, Fynbo, HOU, Galaviz, D, Geissel, H, Gernhaeuser, R, Goebel, 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, HT, Jonson, B, Kalantar-Nayestanaki, N, Kanungo, R, Kelic-Heil, A, Knoebel, R, Kroell, T, Kruecken, R, Kurcewicz, J, Kurz, N, Labiche, M, Langer, C, Le Bleis, T, Lemmon, R, Lepyoshkina, O, Lindberg, S, Machado, J, Marganiec, J, Martinez-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, MV, Rigollet, C, Riisager, K, Roeder, M, Rossi, D, del Rio, J Sanchez, Savran, D, Scheit, H, Simon, H, Sorlin, O, Stoica, V, Streicher, B, Taylor, JT, 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, JS, Woods, P, Yakorev, D, Zhukov, MV, Zilges, A, Zuber, K, and Collaboration, R3B

Published
2017

45. Determination of the neutron-capture rate of 17C for r-process nucleosynthesis

Author

Heine, M. (Marcel), Typel, S., Wu, M.-R., Adachi, T., Aksyutina, Y., Alcantara, J., Altstadt, S., Alvarez-Pol, H., Ashwood, N., Atar, L., 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 Pramanik, U., Diaz Fernandez, P., 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., Gonzalez Diaz, D., 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., Le Bleis, T., 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., Sanchez del Rio, J., 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
Aucun
Published
2017

46. Determination of the Neutron-Capture Rate of $^{17}$C 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., Daniel Bemmerer, 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 Pramanik, U., Diaz Fernandez, P., 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., Gonzalez Diaz, D., 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., Le Bleis, T., 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., Sanchez Del Rio, J., 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., 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., Zuber, K., Helmholtz zentrum für Schwerionenforschung GmbH (GSI), KVI-CART, University of Groningen, University of Groningen [Groningen], Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), R3B Collaboration, Research unit Nuclear & Hadron Physics, and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
astro-ph.SR, Astrophysics - Solar and Stellar Astrophysics, FOS: Physical sciences, Nuclear Experiment (nucl-ex), [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], nucl-ex, Nuclear Experiment, Solar and Stellar Astrophysics (astro-ph.SR)
Abstract

International audience; 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
2017

47. 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., Avdeichikov, T. A. 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 Pramanik, U., Diaz Fernandez, P., 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., Gonzalez Diaz, D., 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., Le Bleis, T., 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., Sanchez Del Rio, J., Savran, D., Scheit, H., Simon, H., Sorlin (Ganil), O., Stoica, V., Streicher, B., Taylor, J. T., Tengblad, O., Terashima, S., Thies, R., Togano, Y., Uberseder, E., 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
r-process, nucleosynthesis, Coulomb dissociation, Nuclear Experiment, radiative neutron capture
Abstract

With the R3B-LAND setup at GSI we have measured exclusive relative-energy spectra of the Coulomb dissociation of 18C at a projectile energy around 425~AMeV on a lead target, which are needed to determine the radiative neutron-capture cross sections of 17C into the ground state of 18C. Those data have been used to constrain theoretical calculations for transitions populating excited states in 18C. This allowed to derive the astrophysical cross section σ∗nγ accounting for the thermal population of 17C target states in astrophysical scenarios. The experimentally verified capture rate is significantly lower than those of previously obtained Hauser-Feshbach estimations at temperatures T9≤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 17C on the production of second- and third-peak elements in contrast to earlier sensitivity studies.

Published
2017

48. TPedge: Progress on Cost-Efficient and Durable Edge-Sealed PV Modules

Author

Mittag, M., Eitner, U., and Neff, T.

Subjects
New Materials and Concepts for Cells and Modules, New Materials and Concepts for Photovoltaic Devices
Abstract

33rd European Photovoltaic Solar Energy Conference and Exhibition; 48-54, With TPedge we present an advanced frameless, polymer free encapsulation concept for silicon solar cells which addresses disadvantages and cost factors related to conventional solar modules. TPedge is a gas-filled, edge sealed, glass-glass module without polymeric encapsulation foils. The cost calculation indicates 5.7% lower costs of ownership for TPedge compared to the conventional module production due to savings for encapsulation foils and frame. Results from successful and extended module testing (i.e. 4000 hours damp-heat, PMPP = -1.3%) and 4 years of outdoor exposure prove good reliability of the concept. We perform a cell-to-module (CTM) analysis of TPedge and other concepts and calculate gain and loss factors. We find TPedge to have increased reflection losses compared to conventional modules and a lower CTMpower ratio (0.906). We combine CTM-analysis and cost calculation and find the specific costs (€/Wp) for TPedge to be 1.2% lower compared to the conventional module concept. Weight analysis shows a lower weight of TPedge modules compared to conventional modules and glassglass laminates (-0.4 kg). A Carbon footprint analysis performed for different module concepts and important module materials shows a lower CO2-footprint of the materials used in TPedge modules compared to conventional modules.

Published
2017
Full Text
View/download PDF

49. Determination of the neutron-capture rate of C-17 for r-process nucleosynthesis

Author

Heine, M., Typel, S., Wu, M. -R., Adachi, T., Aksyutina, Y., Alcantara, J., Altstadt, S., Alvarez-Pol, H., Ashwood, N., Atar, L., 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., Cederkaell, 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., Gernhaeuser, R., Goebel, 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., Knoebel, R., Kroell, T., Kruecken, R., Kurcewicz, J., Kurz, N., Labiche, M., Langer, C., Le Bleis, T., Lemmon, R., Lepyoshkina, O., Lindberg, S., Machado, J., Marganiec, J., Martinez-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., Roeder, 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., Zuber, K., Heine, M., Typel, S., Wu, M. -R., Adachi, T., Aksyutina, Y., Alcantara, J., Altstadt, S., Alvarez-Pol, H., Ashwood, N., Atar, L., 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., Cederkaell, 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., Gernhaeuser, R., Goebel, 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., Knoebel, R., Kroell, T., Kruecken, R., Kurcewicz, J., Kurz, N., Labiche, M., Langer, C., Le Bleis, T., Lemmon, R., Lepyoshkina, O., Lindberg, S., Machado, J., Marganiec, J., Martinez-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., Roeder, 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.

Abstract

With the (RB)-B-3-LAND setup at GSI we have measured exclusive relative-energy spectra of the Coulomb dissociation of C-18 at a projectile energy around 425A MeV on a lead target, which are needed to determine the radiative neutron-capture cross sections of C-17 into the ground state of C-18. Those data have been used to constrain theoretical calculations for transitions populating excited states in C-18. This allowed to derive the astrophysical cross section sigma(n gamma)*. accounting for the thermal population of C-17 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 <= 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 C-17 on the production of second-and third-peak elements in contrast to earlier sensitivity studies.

Published
2017

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