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1. An innovative Superconducting Recoil Separator for HIE-ISOLDE

Author

Martel, I., Acosta, L., Aguado, J. L., Assie, M., Al-Aqeel, M. A. M., Ballarino, A., Barna, D., Berjillos, R., Bonora, M., Bontoiu, C., Borge, M. J. G., Briz, J. A., Bustinduy, I., Bottura, L., Catalina-Medina, L., Catford, W., Cederkall, J., Davinson, T., de Angelis, G., Devred, A., Diaz-Martin, C., Ekelöf, Tord, Felice, H., Fynbo, H., Foussat, A. P., Florin, R., Freeman, S. J., Gaffney, L., Garcia-Ramos, C., Gentini, L., Gonzalez-Cordero, C. A., Guazzoni, C., Haziot, A., Heinz, A., Jimenez, J. M., Johnston, K., Jonson, B., Kirby, G., Kirby, O., Kurtukian-Nieto, T., Labiche, M., Liebsch, M., Losasso, M., Laird, A., Munoz, J. L., Singh, B. S. Nara, Neyens, G., Napiorkowski, P. J., O'Donnell, D., Page, R. D., Perini, D., Resta-Lopez, J., Riddone, G., Rodriguez, J. A., Rodin, V., Russenschuck, S., Sharma, V. R., Salguero-Andujar, F., Sanchez-Segovia, J., Riisager, K., Sanchez-Benitez, A. M., Shepherd, B., Siesling, E., Smallcombe, J., Stanoiu, M., Tengblad, O., Thermeau, J. P., Tommasini, D., Uusitalo, J., Varnasseri, S., Welsch, C. P., Willering, G., Martel, I., Acosta, L., Aguado, J. L., Assie, M., Al-Aqeel, M. A. M., Ballarino, A., Barna, D., Berjillos, R., Bonora, M., Bontoiu, C., Borge, M. J. G., Briz, J. A., Bustinduy, I., Bottura, L., Catalina-Medina, L., Catford, W., Cederkall, J., Davinson, T., de Angelis, G., Devred, A., Diaz-Martin, C., Ekelöf, Tord, Felice, H., Fynbo, H., Foussat, A. P., Florin, R., Freeman, S. J., Gaffney, L., Garcia-Ramos, C., Gentini, L., Gonzalez-Cordero, C. A., Guazzoni, C., Haziot, A., Heinz, A., Jimenez, J. M., Johnston, K., Jonson, B., Kirby, G., Kirby, O., Kurtukian-Nieto, T., Labiche, M., Liebsch, M., Losasso, M., Laird, A., Munoz, J. L., Singh, B. S. Nara, Neyens, G., Napiorkowski, P. J., O'Donnell, D., Page, R. D., Perini, D., Resta-Lopez, J., Riddone, G., Rodriguez, J. A., Rodin, V., Russenschuck, S., Sharma, V. R., Salguero-Andujar, F., Sanchez-Segovia, J., Riisager, K., Sanchez-Benitez, A. M., Shepherd, B., Siesling, E., Smallcombe, J., Stanoiu, M., Tengblad, O., Thermeau, J. P., Tommasini, D., Uusitalo, J., Varnasseri, S., Welsch, C. P., and Willering, G.

Abstract

The ISOLDE Scientific Infrastructure at CERN offers a unique range of post-accelerated radioactive beams. The scientific program can be improved with the "Isolde Superconducting Recoil Separator" (ISRS), an innovative spectrometer able to deliver unprecedented (A, Z) resolution. In this paper we present an overview of the physics and ongoing technical developments.

Published
2023
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2. An innovative Superconducting Recoil Separator for HIE-ISOLDE

Author

Ministerio de Ciencia e Innovación (España), European Commission, Martel, I. [0000-0002-4895-2305], Martel, I., Acosta, L., Aguado, J. L., Assie, M., Al-Aqeel, M. A.M., Ballarino, A., Barna, D., Berjillos, R., Bonora, M., Bontoiu, C., García Borge, María José, Briz, José Antonio, Bustinduy, I., Bottura, L., Catalina-Medina, L., Catford, W., Cederkäll, J., Davinson, T., de Angelis, G., Devred, A., Díaz-Martín, C., Ekelöf, T., Felice, H., Fynbo, H., Foussat, A. P., Florin, R., Freeman, S. J., Gaffney, L., García-Ramos, C., Gentini, L., Gonzalez-Cordero, C. A., Guazzoni, C., Haziot, A., Heinz, A., Jimenez, J. M., Johnston, K., Jonson, B., Kirby, G., Kirby, O., Kurtukian-Nieto, T., Labiche, M., Liebsch, M., Losasso, M., Laird, A., Muñoz, J. L., Nara Singh, B. S., Neyens, G., Napiorkowski, P. J., O'Donnell, D., Page, R. D., Perini, D., Resta-López, J., Riddone, G., Rodriguez, J. A., Rodin, V., Russenschuck, S., Sharma, V. R., Salguero-Andújar, F., Sánchez-Segovia, J., Riisager, K., Sánchez-Benítez, A. M., Shepherd, B., Siesling, E., Smallcombe, J., Stanoiu, M., Tengblad, Olof, Thermeau, J. P., Tommasini, D., Uusitalo, J., Varnasseri, S., Welsch, C. P., Willering, G., Ministerio de Ciencia e Innovación (España), European Commission, Martel, I. [0000-0002-4895-2305], Martel, I., Acosta, L., Aguado, J. L., Assie, M., Al-Aqeel, M. A.M., Ballarino, A., Barna, D., Berjillos, R., Bonora, M., Bontoiu, C., García Borge, María José, Briz, José Antonio, Bustinduy, I., Bottura, L., Catalina-Medina, L., Catford, W., Cederkäll, J., Davinson, T., de Angelis, G., Devred, A., Díaz-Martín, C., Ekelöf, T., Felice, H., Fynbo, H., Foussat, A. P., Florin, R., Freeman, S. J., Gaffney, L., García-Ramos, C., Gentini, L., Gonzalez-Cordero, C. A., Guazzoni, C., Haziot, A., Heinz, A., Jimenez, J. M., Johnston, K., Jonson, B., Kirby, G., Kirby, O., Kurtukian-Nieto, T., Labiche, M., Liebsch, M., Losasso, M., Laird, A., Muñoz, J. L., Nara Singh, B. S., Neyens, G., Napiorkowski, P. J., O'Donnell, D., Page, R. D., Perini, D., Resta-López, J., Riddone, G., Rodriguez, J. A., Rodin, V., Russenschuck, S., Sharma, V. R., Salguero-Andújar, F., Sánchez-Segovia, J., Riisager, K., Sánchez-Benítez, A. M., Shepherd, B., Siesling, E., Smallcombe, J., Stanoiu, M., Tengblad, Olof, Thermeau, J. P., Tommasini, D., Uusitalo, J., Varnasseri, S., Welsch, C. P., and Willering, G.

Abstract

The ISOLDE Scientific Infrastructure at CERN offers a unique range of post-accelerated radioactive beams. The scientific program can be improved with the “Isolde Superconducting Recoil Separator” (ISRS), an innovative spectrometer able to deliver unprecedented (A, Z) resolution. In this paper we present an overview of the physics and ongoing technical developments.

Published
2023

3. Unveiling the two-proton halo character of Ne: Exclusive measurement of quasi-free proton-knockout reactions

Author

Lehr, C., Wamers, F., Aksouh, F., Aksyutina, Yu., Álvarez-Pol, H., Atar, L., Aumann, T., Beceiro-Novo, S., Bertulani, C.A., Boretzky, K., Borge, M.J.G., Caesar, C., Chartier, M., Chatillon, A., Chulkov, L.V., Cortina-Gil, D., Díaz Fernández, P., Emling, H., Ershova, O., Fraile, L.M., Fynbo, H.O.U., Galaviz, D., Geissel, H., Heil, M., Heine, M., Hoffmann, D.H.H., Holl, M., Johansson, H.T., Jonson, B., Karagiannis, C., Kiselev, O.A., Kratz, J.V., Kulessa, R., Kurz, N., Langer, C., Lantz, M., Le Bleis, T., Lemmon, R., Litvinov, Yu.A., Löher, B., Mahata, K., Marganiec-Galązka, J., Müntz, C., Nilsson, T., Nociforo, C., Ott, W., Panin, V., Paschalis, S., Perea, A., Plag, R., Reifarth, R., Richter, A., Riisager, K., Rodriguez-Tajes, C., Rossi, D., Savran, D., Scheit, H., Schrieder, G., Schrock, P., Simon, H., Stroth, J., Sümmerer, K., Tengblad, O., Weick, H., and Wimmer, C.

Abstract

The proton drip-line nucleus $^{17}$Ne is investigated experimentally in order to determine its two-proton halo character. A fully exclusive measurement of the $^{17}$Ne(p,2p)16F→15⁎O+p quasi-free one-proton knockout reaction has been performed at GSI at around 500 MeV/nucleon beam energy. All particles resulting from the scattering process have been detected. The relevant reconstructed quantities are the angles of the two protons scattered in quasi-elastic kinematics, the decay of $^{16}$F into $^{15}$O (including γ decays from excited states) and a proton, as well as the $^{15}$O+p relative-energy spectrum and the $^{16}$F momentum distributions. The latter two quantities allow an independent and consistent determination of the fractions of l=0 and l=2 motion of the valence protons in $^{17}$Ne. With a resulting relatively small l=0 component of only around 35(3)%, it is concluded that $^{17}$Ne exhibits a rather modest halo character only. The quantitative agreement of the two values deduced from the energy spectrum and the momentum distributions supports the theoretical treatment of the calculation of momentum distributions after quasi-free knockout reactions at high energies by taking into account distortions based on the Glauber theory. Moreover, the experimental data allow the separation of valence-proton knockout and knockout from the $^{15}$O core. The latter process contributes with 11.8(3.1) mb around 40% to the total proton-knockout cross section of 30.3(2.3) mb, which explains previously reported contradicting conclusions derived from inclusive cross sections.

Published
2022

4. Unveiling the Two-Proton Halo Character of 17Ne: Exclusive Measurement of Quasi-free Proton-Knockout Reactions

Author

Federal Ministry of Education and Research (Germany), Helmholtz International Center for FAIR, Technische Universität Darmstadt, Swedish Research Council, Russian Foundation for Basic Research, Ministerio de Ciencia e Innovación (España), Department of Energy (US), National Science Foundation (US), Aumann, T. [0000-0003-1660-9294], Lehr, C., Wamers, F., Aksouh, F., Aksyutina, Yu., Alvarez-Pol, H., Atar, L., Aumann, T., Beceiro-Novo, S., Bertulani, C.A., Boretzky, K., García Borge, María José, Caesar, C., Chartier, M., Chatillon, A., Chulkov, L.V., Cortina-Gil, D., Diaz Fernandez, P., Emling, H., Ershova, O., Fraile, Luis M., Fynbo, H.O.U., Galaviz, D., Geissel, H., Heil, M., Heine, M., Hoffmann, D.H.H., Holl, M., Johansson, H.T., Jonson, B., Karagiannis, C., Kiselev, O. A., Kratz, J. V., Kulessa, R., Kurz, N., Langer, C., Lantz, M., Bleis, T. Le, Lemmon, R., Litvinov, Yu. A., Loeher, B., Mahata, K., Marganiec-Galazka, J., Muentz, C., Nilsson, T., Nociforo, C., Ott, W., Panin, V., Paschalis, S., Perea, Ángel, Plag, R., Reifarth, R., Richter, A., Riisager, K., Rodriguez-Tajes, C., Rossi, D., Savran, D., Scheit, H., Schrieder, G., Schrock, R., Simon, H., Stroth, J., Suemmerer, K., Tengblad, Olof, Weick, H., Wimmer, C., Federal Ministry of Education and Research (Germany), Helmholtz International Center for FAIR, Technische Universität Darmstadt, Swedish Research Council, Russian Foundation for Basic Research, Ministerio de Ciencia e Innovación (España), Department of Energy (US), National Science Foundation (US), Aumann, T. [0000-0003-1660-9294], Lehr, C., Wamers, F., Aksouh, F., Aksyutina, Yu., Alvarez-Pol, H., Atar, L., Aumann, T., Beceiro-Novo, S., Bertulani, C.A., Boretzky, K., García Borge, María José, Caesar, C., Chartier, M., Chatillon, A., Chulkov, L.V., Cortina-Gil, D., Diaz Fernandez, P., Emling, H., Ershova, O., Fraile, Luis M., Fynbo, H.O.U., Galaviz, D., Geissel, H., Heil, M., Heine, M., Hoffmann, D.H.H., Holl, M., Johansson, H.T., Jonson, B., Karagiannis, C., Kiselev, O. A., Kratz, J. V., Kulessa, R., Kurz, N., Langer, C., Lantz, M., Bleis, T. Le, Lemmon, R., Litvinov, Yu. A., Loeher, B., Mahata, K., Marganiec-Galazka, J., Muentz, C., Nilsson, T., Nociforo, C., Ott, W., Panin, V., Paschalis, S., Perea, Ángel, Plag, R., Reifarth, R., Richter, A., Riisager, K., Rodriguez-Tajes, C., Rossi, D., Savran, D., Scheit, H., Schrieder, G., Schrock, R., Simon, H., Stroth, J., Suemmerer, K., Tengblad, Olof, Weick, H., and Wimmer, C.

Abstract

The proton drip-line nucleus 17Ne is investigated experimentally in order to determine its two-proton halo character. A fully exclusive measurement of the 17Ne(p,2p)16F->15O+p quasi-free one-proton knockout reaction has been performed at GSI at around 500 MeV/nucleon beam energy. All particles resulting from the scattering process have been detected. The relevant reconstructed quantities are the angles of the two protons scattered in quasi-elastic kinematics, the decay of 16F into 15O (including gamma decays from excited states) and a proton, as well as the 15O+p relative-energy spectrum and the 16F momentum distributions. The latter two quantities allow an independent and consistent determination of the ratio of l=0 and l=2 motion of the valence protons in 17Ne. With a resulting relatively small l=0 component of only around 35(3)%, it is concluded that 17Ne exhibits a rather modest halo character only. The quantitative agreement of the two values deduced from the energy spectrum and the momentum distributions supports the theoretical treatment of the calculation of momentum distributions after quasi-free knockout reactions at high energies by taking into account distortions based on the Glauber theory. Moreover, the experimental data allow the separation of valence-proton knockout and knockout from the 15O core. The latter process contributes with 11.8(3.1) mb around 40% to the total proton-knockout cross section of 30.3(2.3) mb, which explains previously reported contradicting conclusions derived from inclusive cross sections.

Published
2022

5. Unveiling the two-proton halo character of 17Ne: Exclusive measurement of quasi-free proton-knockout reactions

Author

Lehr, C., Wamers, F., Aksouh, F., Aksyutina, Yu., ��lvarez-Pol, H., Atar, Leyla, Aumann, Thomas, Beceiro-Novo, S., Bertulani, C. A., Boretzky, K., Borge, M. J. G., Caesar, C., Chartier, M., Chatillon, A., Chulkov, L. V., Cortina-Gil, D., D��az Fern��ndez, P., Emling, Hans, Ershova, Olga, Fraile, L. M., Fynbo, H. O. U., Galaviz, D., Geissel, H., Heil, M., Heine, M., Hoffmann, D. H. H., Holl, M., Johansson, H. T., Jonson, B., Karagiannis, C., Kiselev, O. A., Kratz, J. V., Kulessa, R., Kurz, N., Langer, Christoph, Lantz, M., Le Bleis, T., Lemmon, R., Litvinov, Yu. A., L��her, B., Mahata, K., Marganiec-Gal��zka, J., M��ntz, C., Nilsson, T., Nociforo, C., Ott, W., Panin, V., Paschalis, S., Perea, A., Plag, Ralf, Reifarth, Rene, Richter, A., Riisager, K., Rodriguez-Tajes, C., Rossi, D., Savran, D., Scheit, H., Schrieder, G., Schrock, P., Simon, H., Stroth, J., S��mmerer, K., Tengblad, O., Weick, H., Wimmer, C., Federal Ministry of Education and Research (Germany), Helmholtz International Center for FAIR, Technische Universität Darmstadt, Swedish Research Council, Russian Foundation for Basic Research, Ministerio de Ciencia e Innovación (España), Department of Energy (US), National Science Foundation (US), Aumann, T. [0000-0003-1660-9294], and Aumann, T.

Subjects
Subatomär fysik, Nuclear and High Energy Physics, Física-Modelos matemáticos, Subatomic Physics, Nuclear Theory, Partículas, FOS: Physical sciences, ddc:530, Nuclear Experiment (nucl-ex), Nuclear experiment, Nuclear Experiment
Abstract

7 pags., 5 figs., The proton drip-line nucleus 17Ne is investigated experimentally in order to determine its two-proton halo character. A fully exclusive measurement of the 17Ne(p,2p)16F->15O+p quasi-free one-proton knockout reaction has been performed at GSI at around 500 MeV/nucleon beam energy. All particles resulting from the scattering process have been detected. The relevant reconstructed quantities are the angles of the two protons scattered in quasi-elastic kinematics, the decay of 16F into 15O (including gamma decays from excited states) and a proton, as well as the 15O+p relative-energy spectrum and the 16F momentum distributions. The latter two quantities allow an independent and consistent determination of the ratio of l=0 and l=2 motion of the valence protons in 17Ne. With a resulting relatively small l=0 component of only around 35(3)%, it is concluded that 17Ne exhibits a rather modest halo character only. The quantitative agreement of the two values deduced from the energy spectrum and the momentum distributions supports the theoretical treatment of the calculation of momentum distributions after quasi-free knockout reactions at high energies by taking into account distortions based on the Glauber theory. Moreover, the experimental data allow the separation of valence-proton knockout and knockout from the 15O core. The latter process contributes with 11.8(3.1) mb around 40% to the total proton-knockout cross section of 30.3(2.3) mb, which explains previously reported contradicting conclusions derived from inclusive cross sections., This work is supported by the German Federal Ministry for Education and Research (BMBF) under contract No. 05P15RDFN1, the ExtreMe Matter Institute (EMMI), HIC for FAIR, and the GSI- TU Darmstadt cooperation agreement. Financial support from the Swedish Research Council, from the Russian Foundation for Ba- sic Research (RFBR Grant 12-02-01115-a), and from the Spanish grants from MICINN AEI FPA2017-87568-P, PGC2018-0099746-B- C21, FPA2015-64969-P, PID2019-104390GB-I00, RTI2018-098868- B-100, and Maria de Maeztu Units of excellence MDM-2016-0692 are also acknowledged. One of us (B. J.) is a Helmholtz Interna- tional Fellow. C.A.B. acknowledges support by the U.S. DOE grant DE-FG02-08ER41533 and the U.S. NSF Grant No. 1415656

Published
2022
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6. Probing proton halo effects in the B+ Zn collision around the Coulomb barrier

Author

Spartà, R., Di Pietro, A., Figuera, P., Tengblad, O., Moro, A.M., Martel, I., Fernández-García, J.P., Lei, Jin, Acosta, L., Borge, M.J.G., Bruni, G., Cederkäll, J., Davinson, T., Ovejas, J.D., Fraile, L.M., Galaviz, D., Halkjaer Jensen, J., Jonson, B., La Cognata, M., Perea, A., Sánchez-Benítez, A.M., Soić, N., and Viñals, S.

Abstract

Proton halo effects in the $^{8}$B+$^{64}$Zn reaction at an energy around 1.5 times the Coulomb barrier have been studied at HIE-ISOLDE CERN using, for the first time, the only existing postaccelerated $^{8}$B beam. This, together with the use of a high granularity and large solid angle detection system, allowed for a careful mapping of the elastic angular distribution, especially in the Coulomb-nuclear interference region. Contrary to what is observed for the one-neutron halo nucleus $^{11}$Be on the same target in a similar energy range, the analysis of the elastic scattering angular distribution shows only a modest suppression of the Coulomb-nuclear interference peak, with no remarkable enhancement of the total reaction cross-section. Inclusive angular and energy distributions of $^{7}$Be produced in direct reaction processes have also been measured. The comparison of these data with the results of theoretical calculations for the elastic and non-elastic breakup contributions indicate that both processes are important. Overall, the experimental data suggest a $^{8}$B collision dynamics at the barrier very different from the one of neutron halo nuclei, showing only modest effects of coupling to continuum. This behaviour can be interpreted as due to the presence of the additional Coulomb interactions halo-core and halo-target together with the presence of the centrifugal barrier felt by the valence proton of $^{8}$B.

Published
2021

7. NeuLAND: The high-resolution neutron time-of-flight spectrometer for (RB)-B-3 at FAIR

Author

Boretzky, K., Gasparic, I, Heil, M., Mayer, J., Heinz, A., Caesar, C., Kresan, D., Simon, H., Toernqvist, H. T., Koerper, D., Alkhazov, G., Atar, L., Aumann, T., Bemmerer, D., Bondarev, S., V, Bott, L. T., Chakraborty, S., Cherciu, M., I, Chulkov, L., V, Ciobanu, M., Datta, U., De Filippo, E., Douma, C. A., Dreyer, J., Elekes, Z., Enders, J., Galaviz, D., Geraci, E., Gnoffo, B., Goebel, K., Golovtsov, V. L., Diaz, D. Gonzalez, Gruzinsky, N., Heftrich, T., Heggen, H., Hehner, J., Hensel, T., Hoemann, E., Holl, M., Horvat, A., Horvath, A., Ickert, G., Malenica, D. Jelavic, Johansson, H. T., Jonson, B., Kahlbow, J., Kalantar-Nayestanaki, N., Kelic-Heil, A., Kempe, M., Koch, K., Kozlenko, N. G., Krivshich, A. G., Kurz, N., Kuznetsov, V, Langer, C., Leifels, Y., Lihtar, I, Loeher, B., Machado, J., Martorana, N. S., Miki, K., Nilsson, T., Orischin, E. M., Pagano, E., V, Pirrone, S., Politi, G., Potlog, P. M., Rahaman, A., Reifarth, R., Rigollet, C., Roeder, M., Rossi, D. M., Russotto, P., Savran, D., Scheit, H., Schindler, F., Stach, D., Stan, E., Gill, J. Stomvall, Teubig, P., Trimarchi, M., Uvarov, L., Volknandt, M., Volkov, S., Wagner, A., Wagner, V, Wranne, S., Yakorev, D., Zanetti, L., Zilges, A., Zuber, K., Boretzky, K., Gasparic, I, Heil, M., Mayer, J., Heinz, A., Caesar, C., Kresan, D., Simon, H., Toernqvist, H. T., Koerper, D., Alkhazov, G., Atar, L., Aumann, T., Bemmerer, D., Bondarev, S., V, Bott, L. T., Chakraborty, S., Cherciu, M., I, Chulkov, L., V, Ciobanu, M., Datta, U., De Filippo, E., Douma, C. A., Dreyer, J., Elekes, Z., Enders, J., Galaviz, D., Geraci, E., Gnoffo, B., Goebel, K., Golovtsov, V. L., Diaz, D. Gonzalez, Gruzinsky, N., Heftrich, T., Heggen, H., Hehner, J., Hensel, T., Hoemann, E., Holl, M., Horvat, A., Horvath, A., Ickert, G., Malenica, D. Jelavic, Johansson, H. T., Jonson, B., Kahlbow, J., Kalantar-Nayestanaki, N., Kelic-Heil, A., Kempe, M., Koch, K., Kozlenko, N. G., Krivshich, A. G., Kurz, N., Kuznetsov, V, Langer, C., Leifels, Y., Lihtar, I, Loeher, B., Machado, J., Martorana, N. S., Miki, K., Nilsson, T., Orischin, E. M., Pagano, E., V, Pirrone, S., Politi, G., Potlog, P. M., Rahaman, A., Reifarth, R., Rigollet, C., Roeder, M., Rossi, D. M., Russotto, P., Savran, D., Scheit, H., Schindler, F., Stach, D., Stan, E., Gill, J. Stomvall, Teubig, P., Trimarchi, M., Uvarov, L., Volknandt, M., Volkov, S., Wagner, A., Wagner, V, Wranne, S., Yakorev, D., Zanetti, L., Zilges, A., and Zuber, K.

Abstract

NeuLAND (New Large-Area Neutron Detector) is the next-generation neutron detector for the (RB)-B-3 (Reactions with Relativistic Radioactive Beams) experiment at FAIR (Facility for Antiproton and Ion Research). NeuLAND detects neutrons with energies from 100 to 1000 MeV, featuring a high detection efficiency, a high spatial and time resolution, and a large multi-neutron reconstruction efficiency. This is achieved by a highly granular design of organic scintillators: 3000 individual submodules with a size of 5 x 5 x 250 cm(3) are arranged in 30 double planes with 100 submodules each, providing an active area of 250 x 250 cm(2) and a total depth of 3 m. The spatial resolution due to the granularity together with a time resolution of sigma(t) <= 150 ps ensures highresolution capabilities. In conjunction with calorimetric properties, a multi-neutron reconstruction efficiency of 50% to 70% for four-neutron events will be achieved, depending on both the emission scenario and the boundary conditions allowed for the reconstruction method. We present in this paper the final design of the detector as well as results from test measurements and simulations on which this design is based.

Published
2021

8. Quasi-free proton knockout from C on carbon target at 398 MeV/u

Author

Panin, V., Holl, M., Taylor, J.T., Aksyutina, Y., Alvarez-Pol, H., Aumann, T., Bertulani, C.A., Boretzky, K., Caesar, C., Chartier, M., Chulkov, L.V., Cortina-Gil, D., Enders, J., Ershova, O., Geissel, H., Gernhäuser, R., Heil, M., Johansson, H.T., Jonson, B., Kelić-Heil, A., Kiselev, O., Langer, C., Le Bleis, T., Lemmon, R., Nilsson, T., Paschalis, S., Petri, M., Plag, R., Reifarth, R., Rossi, D., Scheit, H., Simon, H., Wamers, F., Weick, H., and Wimmer, C.

Abstract

The proton-removal mechanism of the $^{12}$C→11B reaction induced on a carbon target via elementary nucleon-nucleon scattering is investigated in exclusive triple-coincidence measurements. The observed two-nucleon angular correlations are found to be consistent with quasi-free scattering of a projectile-like proton off a target-like nucleon. Exclusive cross sections for one-step pp and pn interactions are determined as σpp=17.2(12) mb and σpn=18.2(18), respectively. The extracted quasi-free component amounts up to 58(4)% of the total proton-removal cross section. The results are compared to total proton-removal cross sections obtained from the experiment and eikonal reaction theory.

Published
2019

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., Caamano, M., Caesar, C., Casarejos, E., Catford, W., Cederkall, J., Chakraborty, S., Chulkov, L., V, Cortina-Gil, D., Cravo, E., Crespo, R., Pramanik, U. Datta, Dillmann, I, Fernandez, P. Diaz, Elekes, Z., Enders, J., Farinon, F., Fraile, L. M., Galaviz, D., Geissel, H., Gernhaeuser, R., Golubev, P., Goebel, K., Heil, M., Heine, M., Heinz, A., Henriques, A., Holl, M., Johansson, H. T., Jonson, B., Kalantar-Nayestanaki, N., Kanungo, R., Kelic-Heil, A., Kroll, T., Kurz, N., Langer, C., Le Bleis, T., Machado, J., Marganiec-Galazka, J., Nacher, E., Nilsson, T., Nociforo, C., Panin, V, Perea, A., Pietri, S. B., Plag, R., Rahaman, A., 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., Wamers, F., Wheldon, C., Wilson, G. L., Winfield, J. S., Weick, H., Woods, P., Yakorev, D., Zhukov, M., Zilges, A., Zuber, K., 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., Caamano, M., Caesar, C., Casarejos, E., Catford, W., Cederkall, J., Chakraborty, S., Chulkov, L., V, Cortina-Gil, D., Cravo, E., Crespo, R., Pramanik, U. Datta, Dillmann, I, Fernandez, P. Diaz, Elekes, Z., Enders, J., Farinon, F., Fraile, L. M., Galaviz, D., Geissel, H., Gernhaeuser, R., Golubev, P., Goebel, K., Heil, M., Heine, M., Heinz, A., Henriques, A., Holl, M., Johansson, H. T., Jonson, B., Kalantar-Nayestanaki, N., Kanungo, R., Kelic-Heil, A., Kroll, T., Kurz, N., Langer, C., Le Bleis, T., Machado, J., Marganiec-Galazka, J., Nacher, E., Nilsson, T., Nociforo, C., Panin, V, Perea, A., Pietri, S. B., Plag, R., Rahaman, A., 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., Wamers, F., Wheldon, C., Wilson, G. L., Winfield, J. S., Weick, H., Woods, P., Yakorev, D., Zhukov, M., Zilges, A., and Zuber, K.

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 N-A(p,2p)CA-1 quasi-free scattering reactions to measure the proton component of the 2(1)(+) state of C-16,C-18,C-20. 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. (C) 2020 The Authors. Published by Elsevier B.V.

Published
2020

10. Coulomb and nuclear excitations of narrow resonances in Ne

Author

Marganiec, J., Wamers, F., Aksouh, F., Aksyutina, Yu., Álvarez-Pol, H., Aumann, T., Beceiro-Novo, S., Bertulani, C.A., Boretzky, K., Borge, M.J.G., Chartier, M., Chatillon, A., Chulkov, L.V., Cortina-Gil, D., Emling, H., Ershova, O., Fraile, L.M., Fynbo, H.O.U., Galaviz, D., Geissel, H., Heil, M., Hoffmann, D.H.H., Hoffmann, J., Johansson, H.T., Jonson, B., Karagiannis, C., Kiselev, O.A., Kratz, J.V., Kulessa, R., Kurz, N., Langer, C., Lantz, M., Le Bleis, T., Lemmon, R., Litvinov, Yu.A., Mahata, K., Müntz, C., Nilsson, T., Nociforo, C., Nyman, G., Ott, W., Panin, V., Paschalis, S., Perea, A., Plag, R., Reifarth, R., Richter, A., Rodriguez-Tajes, C., Rossi, D., Riisager, K., Savran, D., Schrieder, G., Simon, H., Stroth, J., Sümmerer, K., Tengblad, O., Typel, S., Weick, H., Wiescher, M., and Wimmer, C.

Abstract

New experimental data for dissociation of relativistic 17Ne projectiles incident on targets of lead, carbon, and polyethylene targets at GSI are presented. Special attention is paid to the excitation and decay of narrow resonant states in 17Ne. Distributions of internal energy in the O15+p+p three-body system have been determined together with angular and partial-energy correlations between the decay products in different energy regions. The analysis was done using existing experimental data on 17Ne and its mirror nucleus 17N. The isobaric multiplet mass equation is used for assignment of observed resonances and their spins and parities. A combination of data from the heavy and light targets yielded cross sections and transition probabilities for the Coulomb excitations of the narrow resonant states. The resulting transition probabilities provide information relevant for a better understanding of the 17Ne structure.

Published
2016

11. Coulomb and nuclear excitations of narrow resonances in 17Ne

Author

Universidade de Santiago de Compostela. Departamento de Física de Partículas, Marganiec, J., Wamers, F., Aksouh, F., Aksyutina, Y., Álvarez Pol, Héctor, Aumann, T., Beceiro Novo, Saúl, Bertulani, C. A., Boretzky, K., Borge, M. J. G., Chartier, M., Chatillon, A., Chulkov, L. V., Cortina Gil, María Dolores, Emling, H., Ershova, O., Fraile, L. M., Fynbo, H. O. U., Galaviz, D., Geissel, H., Heil, M., Hoffmann, D. H. H., Hoffmann, J., Johansson, H. T., Jonson, B., Karagiannis, C., Kiselev, O. A., Kratz, J. V., Kulessa, R., Kurz, N., Langer, C., Lantz, M., Le Bleis, T., Lemmon, R., Litvinov, Yu. A., Mahata, K., Müntz, C., Nilsson, T., Nociforo, C., Nyman, G., Ott, W., Panin, V., Paschalis, S., Perea, A., Plag, R., Reifarth, R., Richter, A., Rodríguez Tajes, Carme, Rossi, D., Riisager, K., Savran, D., Schrieder, G., Simon, H., Stroth, J., Sümmerer, K., Tengblad, O., Typel, S., Weick, H., Wiescher, M., Wimmer, C., Universidade de Santiago de Compostela. Departamento de Física de Partículas, Marganiec, J., Wamers, F., Aksouh, F., Aksyutina, Y., Álvarez Pol, Héctor, Aumann, T., Beceiro Novo, Saúl, Bertulani, C. A., Boretzky, K., Borge, M. J. G., Chartier, M., Chatillon, A., Chulkov, L. V., Cortina Gil, María Dolores, Emling, H., Ershova, O., Fraile, L. M., Fynbo, H. O. U., Galaviz, D., Geissel, H., Heil, M., Hoffmann, D. H. H., Hoffmann, J., Johansson, H. T., Jonson, B., Karagiannis, C., Kiselev, O. A., Kratz, J. V., Kulessa, R., Kurz, N., Langer, C., Lantz, M., Le Bleis, T., Lemmon, R., Litvinov, Yu. A., Mahata, K., Müntz, C., Nilsson, T., Nociforo, C., Nyman, G., Ott, W., Panin, V., Paschalis, S., Perea, A., Plag, R., Reifarth, R., Richter, A., Rodríguez Tajes, Carme, Rossi, D., Riisager, K., Savran, D., Schrieder, G., Simon, H., Stroth, J., Sümmerer, K., Tengblad, O., Typel, S., Weick, H., Wiescher, M., and Wimmer, C.

Abstract

New experimental data for dissociation of relativistic 17Ne projectiles incident on targets of lead, carbon, and polyethylene targets at GSI are presented. Special attention is paid to the excitation and decay of narrow resonant states in 17Ne. Distributions of internal energy in the 15O +p +pthree-body system have been determined together with angular and partial-energy correlations between the decay products in different energy regions. The analysis was done using existing experimental data on 17Ne and its mirror nucleus 17N. The isobaric multiplet mass equation is used for assignment of observed resonances and their spins and parities. A combination of data from the heavy and light targets yielded cross sections and transition probabilities for the Coulomb excitations of the narrow resonant states. The resulting transition probabilities provide information relevant for a better understanding of the 17Ne structure.

Published
2016

12. An appropriate inspiratory flow pattern can enhance CO2 exchange, facilitating protective ventilation of healthy lungs

Author

Walther Sturesson, Louise, Malmkvist, G., Allvin, S., Collryd, M., Bodelsson, M., Jonson, B., Walther Sturesson, Louise, Malmkvist, G., Allvin, S., Collryd, M., Bodelsson, M., and Jonson, B.

Abstract

Background In acute lung injury, CO2 exchange is enhanced by prolonging the volume-weighted mean time for fresh gas to mix with resident alveolar gas, denoted mean distribution time (MDT), and by increasing the flow rate immediately before inspiratory flow interruption, end-inspiratory flow (EIF). The objective was to study these effects in human subjects without lung disease and to analyse the results with respect to lung-protective ventilation of healthy lungs. Methods During preparation for intracranial surgery, the lungs of eight subjects were ventilated with a computer-controlled ventilator, allowing breath-by-breath modification of the inspiratory flow pattern. The durations of inspiration (TI) and postinspiratory pause (TP) were modified, as was the profile of the inspiratory flow wave (i.e. constant, increasing, or decreasing). The single-breath test for CO2 was used to quantify airway dead space (VDaw) and CO2 exchange. Results A long MDT and a high EIF augment CO2 elimination by reducing VDaw and promoting mixing of tidal gas with resident alveolar gas. A heat and moisture exchanger had no other effect than enlarging VDaw. A change of TI from 33 to 15% and of TP from 10 to 28%, leaving the time for expiration unchanged, would augment tidal elimination of CO2 by 14%, allowing a 10% lower tidal volume. Conclusions In anaesthetized human subjects without lung disease, CO2 exchange is enhanced by a long MDT and a high EIF. A short TI and a long TP allow significant reduction of tidal volume when lung-protective ventilation is required. Clinical trial registration NCT01686984.

Published
2016

13. Be11(βp), a quasi-free neutron decay?

Author

Riisager, K., Forstner, O., Borge, M.J.G., Briz, J.A., Carmona-Gallardo, M., Fraile, L.M., Fynbo, H.O.U., Giles, T., Gottberg, A., Heinz, A., Johansen, J.G., Jonson, B., Kurcewicz, J., Lund, M.V., Nilsson, T., Nyman, G., Rapisarda, E., Steier, P., Tengblad, O., Thies, R., and Winkler, S.R.

Subjects
Halo nucleus, 11Be, Nuclear Theory, Partículas, Physics::Accelerator Physics, High Energy Physics::Experiment, Beta decay, Nuclear Experiment
Abstract

We have observed β− -delayed proton emission from the neutron-rich nucleus 11 Be by analyzing a sample collected at the ISOLDE facility at CERN with accelerator mass spectrometry (AMS). With a branching ratio of (8.3±0.9)⋠10−6 the strength of this decay mode, as measured by the BGT -value, is unexpectedly high. The result is discussed within a simple single-particle model and could be interpreted as a quasi-free decay of the 11 Be halo neutron into a single-proton state.

Published
2014

14. Systematic investigation of the drip-line nuclei Li-11 and Be-14 and their unbound subsystems Li-10 and Be-13

Author

Simon, H., Meister, M., Aumann, T., García Borge, María José, Chulkov, L. V., Pramanik, U. Datta, Elze, Th. W., Emling, H., Forssén, C., Geissel, H., Hellstroem, M., Jonson, B., Kratz, Jx., Kulessa, R., Nilsson, T., Nyman, G., Richter, Achim W., Riisager, K., Scheidenberger, C., Schrieder, G., Tengblad, Olof, and Zhukov, M. V.

Subjects
Reaction Cross-Sections, N=8 Shell Closure, Halo Nuclei, Excited-States, Energy-Levels, Ground-State, Fragmentation Reactions, Cluster models, Momentum Distributions, He-6
Abstract

36 pages, 10 figures, 8 tables, 3 appendices.-- PACS nrs.: 27.20.+n; 24.70.+s.-- Printed version published Jul 15, 2007., Fragmentation reactions in a carbon target with beams of Li-11 and Be-14 at relativistic energies have been studied in a kinematically complete experiment at the ALADIN-LAND setup at GSI. Excited states in Li-11 and Be-14 were obtained from the data in the inelastic channel. The measured cross sections with the core nucleus in the final state show that in the Be-14 case core polarization plays an important role. In the one-neutron knockout channels the measured angular correlations between fragment and neutron are asymmetric, which demonstrates the presence of states with different parities in the Li-11 and Be-14 ground states. For Li-10 a low-lying virtual s-state, a p-state and evidence for a d-state could be extracted from the data, while the Be-12 + n system shows resonances with more complicated structure., This work was supported by the BMBF under Contracts No. 06 DA 115, No. 06 OF 838 and No. 06 MZ 864 I and by GSI via Hochschulzusammenarbeitsvereinbarungen under Contracts No. DA RICK, No. OF ELZ, No. MZ KRAK and partly supported by the Polish Committee of Scientific Research under Contract No. KBN/2P03B/144/10, CICYT under Contract No. FPA2005-02379 (MJGB, OT), RFBR under Contract No. 04-02-17251, EC under Contract No. ERBCHGE-CT92-0003, and under the auspices of the US Department of Energy by the University of California, Lawrence Livermore National Laboratory under contract No.W-7405-Eng-48. One of us (T.N.) is a Royal Swedish Academy of Sciences Research Fellow supported by a grant from the Knut and Alice Wallenberg Foundation.

Published
2007

15. THERMAL SPECTROMETRY OF PARTICLES AND γ-RAYS WITH COOLED COMPOSITE BOLOMETERS OF MASS UP TO 25 GRAMS

Author

CORON, N., primary, ARTZNER, G., additional, de MARCILLAC, P., additional, STROKE, H., additional, BENOIT, A., additional, AMOUDRY, F., additional, RAVN, H., additional, JONSON, B., additional, TORRE, J.P., additional, TESTARD, O., additional, DAMBIER, G., additional, LEBLANC, J., additional, JEGOUDEZ, G., additional, and LEPELTIER, J.P., additional

Published
1989
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16. News on C-12 from β-decay studies

Author

Fynbo, H.O.U., Diget, C. Aa., Prezado, Yolanda, Äystö, Juha, Bergmann, U. C., Cederkäll, J., Dendooven, P., Fraile, Luis M., Franchoo, S., Fulton, B. R., Huang, W., Huikari, J., Jeppesen, H., Jokinen, A., Jonson, B., Jones, P., Köster, U., Meister, M., Nilsson, T., Nyman, G., García Borge, María José, Riisager, K., Rinta-Antila, S., Storgaard Vogelius, I., Tengblad, Olof, Turrrión, Manuela, Wang, Y., Weissman, L., and Wilhelmsen, K.

Abstract

7 pages, 2 figures.-- Printed version published Jun 28, 2004.-- Issue title: Proceedings of the 8th International Conference on Clustering Aspects of Nuclear Structure and Dynamics (Nara, Japan, Nov 24-29, 2003)., We discuss the importance of the spectroscopic properties of the resonances of C-12 just above the 3α-threshold, and review the existing experimental information of this region with emphasis on 0(+) and 2(+) states. A new experimental approach for studying the β-decays of B-12 and N-12 is presented based on techniques developed in the context of Radioactive beam (rare isotope) physics. Finally preliminary results from an ongoing analysis of two recent experiments are given.

Published
2004

17. New information on C-12 states from the decays of N-12 and B-12

Author

Fynbo, H.O.U., Bergmann, U. C., García Borge, María José, Dendooven, P., Diget, C. Aa., Huang, W., Huikari, J., Jeppesen, H., Jonson, B., Jones, P., Meister, M., Nyman, G., Prezado, Yolanda, Riisager, K., Storgaard Vogelius, I., Tengblad, Olof, Wang, Y., Weissman, L., Wilhelmsen Rolander, K., and Äystö, Juha

Abstract

3 pages, 1 figure., The properties of states in C-12 above the 3α-threshold are of high current interest for nuclear astrophysics and for the nuclear many-body problem in general. We have initiated a series of experiments aimed at elucidating this region by using the β-decays of N-12 and B-12. By applying the ISOL method for producing these radioactive isotopes, in combination with modern segmented charged particle detectors, our approach has significant advantages over previous studies of this region., This work was supported by the European Union Fifth Framework Programme “Improving Human Potential - Access to Research Infrastructure”, and by the Academy of Finland under the Finnish Centre of Excellence Programme 2000–2005 (Project No. 44875, Nuclear and Condensed Matter Physics Programme at JYFL).

Published
2003

18. Proton dripline studies at ISOLDE: Ar-31 and C-9

Author

Borge, Mjg, Fraile, Lm, Olof Tengblad, Bergmann, Uoc, Fynbo, Hou, Mukha, I., Riisager, K., Axelsson, L., Jonson, B., Nyman, G., Markenroth, K., Aysto, J., Honkanen, A., Jokinen, A., Oinonen, M., Jading, Y., Martel, I., Nilsson, T., and Wenander, F.

Abstract

5 pages, 1 figure.-- Printed version published Apr 22, 2002., In this contribution examples of the application of new technologies to disentangle the mechanism of β-delayed multiparticle emission are given. In particular the mechanism of beta-delayed two-proton emission from Ar-31 has been resolved and proved to be sequential, a preview of C-9-decay data is discussed.

Published
2002

19. Momentum profile analysis in one-neutron knockout from Borromean nuclei

Author

SCOAP, Aksyutina, Y., Aumann, T., Boretzky, K., García Borge, María José, Caesar, C., Chatillon, A., Chulkov, L. V., Cortina-Gil, D., Datta Pramanik, U., Emling, H., Fynbo, H.O.U., Geissel, H., Ickert, G., Johansson, H.T., Jonson, B., Kulessa, R., Langer, C., LeBleis, T., Mahata, K., Münzenberg, G., Nilsson, T., Nyman, G., Palit, R., Paschalis, S., Prokopowicz, W., Reifarth, R., Rossi, D., Richter, A., Riisager, K., Schrieder, G., Simon, H., Sümmerer, K., Tengblad, Olof, Weick, H., Zhukov, M. V., SCOAP, Aksyutina, Y., Aumann, T., Boretzky, K., García Borge, María José, Caesar, C., Chatillon, A., Chulkov, L. V., Cortina-Gil, D., Datta Pramanik, U., Emling, H., Fynbo, H.O.U., Geissel, H., Ickert, G., Johansson, H.T., Jonson, B., Kulessa, R., Langer, C., LeBleis, T., Mahata, K., Münzenberg, G., Nilsson, T., Nyman, G., Palit, R., Paschalis, S., Prokopowicz, W., Reifarth, R., Rossi, D., Richter, A., Riisager, K., Schrieder, G., Simon, H., Sümmerer, K., Tengblad, Olof, Weick, H., and Zhukov, M. V.

Abstract

One-neutron knockout reactions from Borromean nuclei are analyzed using a profile function analysis technique. The profile function, which is derived as the square root of the variance of the measured fragment + neutron momenta as a function of their relative energy, is shown to be very sensitive to the angular momentum of the knocked out neutron. Three cases are studied here: 7He, where the profile function analysis shows a presence of (s1/2)2 component in the 8He ground-state wave-function, 10Li, where the presence of a 11(2)% d-wave contribution to the relative energy spectrum above 1.5 MeV is found and, finally, the presence of a major s contribution around 0.5 MeV relative energy in the 13Be case and that the observed decay to the 12Be 2+ state originates in a d state in 13Be. © 2012 Elsevier Open access under CC BY license.

Published
2013

20. Exploring the dipole polarizability of 11Li at REX-ISOLDE

Author

Andrés, M V, García-Borge, M J, Cortina-Gil, M D, Fraile-Prieto, L M, Fynbo, H O U, Gómez-Camacho, J, Guillemaud-Müller, D, Jonson, B, Marqués, F M, Martel, I, Meister, M, Müller, A, Nagarajan, M A, Nyman, G H, Riisager, K, Rubio, B, Schrieder, G, Taín, J L, Tengblad, O, and Wenander, F

Subjects
Physics, Nuclear and High Energy Physics, Dipole, Polarizability, Nuclear Theory, Physics::Atomic Physics, Detectors and Experimental Techniques, Atomic physics, Nuclear Experiment
Abstract

4 pages, 2 figures, 1 table.-- El pdf del artículo es la versión post-print., Dipole polarizability refers to the effect of the excitation to negative parity states through the electric dipole interaction. In nuclear reactions induced by stable beams, dipole polarizability does not play a major role. For nuclei close to the drip lines where the separation energies of neutrons or protons are small, a substantial part of the dipole strength function occurs at low excitation energies. We propose to investigate this effect by measuring elastic scattering and break-up of Li-11 at energies below the Coulomb barrier.

Published
2001

21. On the β-decay of C-9

Author

Bergmann, U. C., García Borge, María José, Boutami, Rafik, Fraile, Luis M., Fynbo, H.O.U., Hornshøj, P., Jonson, B., Markenroth, K., Martel, Ismael, Mukha, I., Nilsson, T., Nyman, G., Oberstedt, A., Prezado, Yolanda, Riisager, K., Simon, H., Tengblad, Olof, Wenander, F., and Wilhelmsen Rolander, K.

Subjects
Decay mechanism features, States, Drip-line, E-α, Li-9, pαα-coin, Asymmetry, Measured β-delayed E-p, B-9 deduced β-branching strengths, Double-sided silicon strip detectors, Shell-Model, Mass-separated source, Emission, A=9 β-decay asymmetry, Radioactivity C-9(β(+)) [from O,Ca(p,X)], Angular correlations, Nuclear system, Continuum, Delayed proton, Light-nuclei
Abstract

24 pages, 9 figures.-- PACS nrs.: 23.40.Hc; 27.20.+n; 24.80.+y.-- Available online 17 August 2001., In β-decay experiments on C-9 at CERN/ISOLDE the β-strength was determined to the ground state, the 12.2 MeV excited state and the Isobaric Analog State (IAS) at 14.655 MeV in B-9. A large β-strength asymmetry is deduced for the mirror transitions of C-9 and Li-9 to states around 12 MeV excitation energy. A satisfactory description of the three-body decay from a narrow energy region around the 12.2 MeV resonance is obtained within a sequential model involving the ground and first-excited states of Li-5 and Be-8. From the study of angular correlations the spin of the 12.2 MeV state is determined as 5/2(-). For the first time the population of the IAS is observed in β-decay and new information on the decay of this state is obtained. The advantages of a closely packed. highly segmented detector setup are demonstrated., This work was partly supported by BMBF, contract number 06DA915I and GSI contract number DARIK. The work was also partly supported by the Spanish CICYT “Plan Nacional de Altas Energías” under contract AEN-99-1046-C02-01.

Published
2001

22. Halo excitations in fragmentation of He-6 at 240 MeV/u on carbon and lead targets

Author

Aleksandrov, D., Aumann, T., Axelsson, L., Baumann, T., García Borge, María José, Chulkov, L. V., Cub, J., Dostal, W., Eberlein, B., Elze, Th. W., Emling, H., Geissel, H., Goldberg, V. Z., Grünschloß, A., Hellström, M., Holeczek, J., Holzmann, R., Jonson, B., Kratz, J. V., Kraus, G., Kulessa, R., Leifels, Y., Leistenschneider, A., Leth, T., Markenroth, K., Meister, M., Mukha, I., Münzenberg, G., Nickel, F., Nilsson, T., Nyman, G., Petersen, B., Pfützner, M., Pribora, V., Richter, Achim W., Riisager, K., Scheidenberger, C., Schrieder, G., Schwab, W., Simon, H., Smedberg, M. H., Stroth, J., Surowiec, A., Tengblad, Olof, and Zhukov, M. V.

Subjects
Inelastic scattering, States, Breakup, Resonances, Spectrum, C-12, Nuclei, Model, Be-11
Abstract

14 pages, 6 figures.-- PACS nrs.: 27.20.+n; 24.70.+. Dissociation of a 240 MeV/u beam of He-6, incident on carbon and lead targets, has been studied in kinematically complete experiments to investigate low-lying excitation modes in the halo nucleus He-6. It is shown that alignment effects characterize the inelastic scattering and allow an unambiguous assignment of the spin of a narrow resonance observed in the excitation energy spectrum. The differential cross sections for the He-6 inelastic scattering on carbon and lead targets were deduced from the measured moments of the two neutrons and the a-particle. An analysis of these distributions shows that quadrupole and, possibly, monopole excitations characterize the hadronic interaction, while the dipole mode is dominating in Coulomb dissociation. Neither theoretically predicted new resonance states in He-6 nor nuclear excitation of a dipole mode were found. Direct evidence has been obtained for strong suppression of Coulornb post-acceleration in direct Coulomb breakup in a lead target. This work was supported by the BMBF under Contracts 06 DA 820, 06 OF 112 and 06 MZ 864 and by GSI via Hochschulzusammenarbeitsvereinbarungen under Contracts DA RICK, OF ELZ, MZ KRK and partly supported by the Polish Committee of Scientific Research under Contract PBZ/PB03/113/09, EC under contract ER-BCHGE-CT92-0003, CICYT under contract AEN92-0788-C02-02 MJGB.and WTZ under contract RUS 609-96. One of us (B.J.) acknowledges the support through an Alexander von Humboldt Research Award.

Published
2000
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23. Determination of the spin of Ar-31

Author

Thaysen, J., Axelsson, L., Äystö, Juha, García Borge, María José, Fraile, Luis M., Fynbo, H.O.U., Honkanen, A., Hornshøj, P., Jading, Y., Jokinen, A., Jonson, B., Martel, Ismael, Mukha, I., Nilsson, T., Nyman, G., Oinonen, M., Riisager, K., Siiskonen, T., Smedberg, M. H., Tengblad, Olof, and Wenander, F.

Subjects
[PACS] Properties of specific nuclei listed by mass ranges: 20 ≤ A ≤ 38, [PACS] Spin, parity, and isobaric spin, 20 ≤ A ≤ 38 [[PACS] Properties of specific nuclei listed by mass ranges], Ar-31,Ar-32,Ar-33(βp), Measured E-p(Θ(βp)), Deduced angular-correlation parameters, [PACS] Weak-interaction and lepton (including neutrino) aspects, [PACS] Other topics in radioactive decay and in-beam spectroscopy, Nuclear spin J, Beta-decay
Abstract

5 pages, 3 figures, 1 table.-- PACS nrs.: 21.10.Hw; 23.40.Bw; 23.90.+w; 27.30.+t., The beta-delayed proton emission from the lightest Ar-isotopes has been recorded with a high-granularity, large solid-angle Si-detector set-up. Proton energy shifts due to beta-recoil have been measured. We demonstrate how this allows the spin of Ar-31 to be determined as 5/2. The method can be applied at decay rates as low as 1 s(-1).

Published
1999

24. New results on the halo structure of B-8

Author

Smedberg, M. H., Baumann, T., Aumann, T., Axelsson, L., Bergmann, U., García Borge, María José, Cortina-Gil, D., Fraile, Luis M., Geissel, H., Grigorenko, L., Hellström, M., Ivanov, M., Iwasa, N., Janik, R., Jonson, B., Lenske, H., Markenroth, K., Münzenberg, G., Nilsson, T., Richter, Achim W., Riisager, K., Scheidenberger, C., Schrieder, G., Schwab, W., Simon, H., Sitar, B., Strmen, P., Sümmerer, K., Winkler, M., and Zhukov, M. V.

Subjects
Breakup reactions, 6 ≤ A ≤ 19 [[PACS] Properties of specific nuclei listed by mass ranges], One-proton removal cross section, Nuclear structure, Momentum distributions, [PACS] Breakup and momentum distributions, [PACS] Properties of specific nuclei listed by mass ranges: 6 ≤ A ≤ 19, Unstable nuclei
Abstract

7 pages, 1 table, 3 figures.-- PACS nrs.: 25.60.Gc; 27.20.+n., The longitudinal momentum distribution of Be-7 fragments after fragmentation of B-8 and the one-proton removal cross section (σ(-1p)) in a carbon target were measured at 1440 MeV/u with the fragment separator FRS used as an energy-loss spectrometer. The results show a narrow momentum distribution with a FWHM value of 91 ± 5 MeV/c and a large cross-section, σ(-1p) = 98 ± 6 mb. Both these results support the interpretation of a spatially extended proton orbit forming a halo in the B-8 ground state. The momentum distribution and the: one-proton removal cross section are shown to be reproduced with a three-body wave function for B-8 where the target is treated as a black disc in the breakup process., This work was supported by the German Federal Minister for Education and Research BMBF under Contracts 06 DA 820, 06 OF 474, and 06 MZ 476 and by GSI via Hochschulzusammenarbeitsvereinbarungen under Contracts DARIK, OF ELK, and MZ KRK. It was partly supported by the Polish Committee of Scientific Research under Contract PB2/P03B/113/09, EC under Contract ERBCHGE-CT92-0003, CICYT under Contract AEN96-1679 (MJGB, LMF), and by Deutsche Forschungsgemeinschaft (DFG)under Contract 436 RUS 130/127/1 and Le-439/1. One of us (B.J.) acknowledges the support through an Alexander von Humboldt Research Award.

Published
1999

25. The unbound isotopes 9,10He

Author

Johansson, H. T., Aksyutina, Yu., Aumann, T., Boretzky, K., Borge, M. J. G., Chatillon, A., Chulkov, L. V., Cortina-Gil, D., Pramanik, U. Datta, Emling, H., Forssén, C., Fynbo, H. O. U., Geissel, H., Ickert, G., Jonson, B., Kulessa, R., Langer, C., Lantz, Mattias, LeBleis, T., Mahata, K., Meister, M., Münzenberg, G., Nilsson, T., Nyman, G., Palit, R., Paschalis, S., Prokopowicz, W., Reifarth, R., Richter, A., Riisager, K., Schrieder, G., Simon, H., Sümmerer, K., Tengblad, O., Weick, H., Zhukov, M. V., Johansson, H. T., Aksyutina, Yu., Aumann, T., Boretzky, K., Borge, M. J. G., Chatillon, A., Chulkov, L. V., Cortina-Gil, D., Pramanik, U. Datta, Emling, H., Forssén, C., Fynbo, H. O. U., Geissel, H., Ickert, G., Jonson, B., Kulessa, R., Langer, C., Lantz, Mattias, LeBleis, T., Mahata, K., Meister, M., Münzenberg, G., Nilsson, T., Nyman, G., Palit, R., Paschalis, S., Prokopowicz, W., Reifarth, R., Richter, A., Riisager, K., Schrieder, G., Simon, H., Sümmerer, K., Tengblad, O., Weick, H., and Zhukov, M. V.

Abstract

The unbound nuclei 9He and 10He have been produced in proton-knockout reactions from a 280 MeV/u 11Li beam impinging on a liquid hydrogen target at the ALADIN-LAND setup at GSI. Information on their nuclear structure has been obtained from the relative-energy spectra, 8He + n and 8He + 2n, employing reaction models incorporating the structure of 11Li.

Published
2010
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26. Structure of 33Mg sheds new light on the island of inversion

Author

Kanungo, R., Nociforo, C., Prochazka, A., Utsuno, Y., Aumann, T., Boutin, D., Cortina-Gil, D., Davids, B., Diakaki, M., Farinon, F., Geissel, H., Gernhäuser, R., Gerl, J., Janik, R., Jonson, B., Kindler, B., Knöbel, R., Krücken, R., Lantz, Mattias, Lenske, H., Litvinov, Y., Mahata, K., Maierbeck, P., Musumarra, A., Nilsson, T., Otsuka, T., Perro, C., Scheidenberger, C., Sitar, B., Strmen, P., Sun, B., Szarka, I., Tanihata, I., Weick, H., Winkler, M., Kanungo, R., Nociforo, C., Prochazka, A., Utsuno, Y., Aumann, T., Boutin, D., Cortina-Gil, D., Davids, B., Diakaki, M., Farinon, F., Geissel, H., Gernhäuser, R., Gerl, J., Janik, R., Jonson, B., Kindler, B., Knöbel, R., Krücken, R., Lantz, Mattias, Lenske, H., Litvinov, Y., Mahata, K., Maierbeck, P., Musumarra, A., Nilsson, T., Otsuka, T., Perro, C., Scheidenberger, C., Sitar, B., Strmen, P., Sun, B., Szarka, I., Tanihata, I., Weick, H., and Winkler, M.

Abstract

The first reaction spectroscopy on the ground state structure of 33Mg through the measurement ofthe longitudinal momentum distribution from the one-neutron removal reaction using a C target at 898 A MeV is reported. The experiment was performed at the FRS, GSI. The distribution has a relativelynarrow width (150 ± 3 MeV/c (FWHM)) and the one-neutron removal cross-section is 74 ± 4 mb. An in-creased contribution from the 2p3/2 orbital is required to explain the observation showing its loweringcompared to existing model predictions. This provides new information regarding the configuration of 33Mg and the island of inversion.

Published
2010
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27. Three-body correlations in the decay of 10He and 13Li

Author

Johansson, H. T., Aksyutina, Yu., Aumann, T., Boretzky, K., Borge, M. J. G., Chatillon, A., Chulkov, L. V., Cortina-Gil, D., Pramanik, U. Datta, Emling, H., Forssén, C., Fynbo, H. O. U., Geissel, H., Ickert, G., Jonson, B., Kulessa, R., Langer, C., Lantz, Mattias, LeBleis, T., Mahata, K., Meister, M., Münzenberg, G., Nilsson, T., Nyman, G., Palit, R., Paschalis, S., Prokopowicz, W., Reifarth, R., Richter, A., Riisager, K., Schrieder, G., Shulgina, N. B., Simon, H., Sümmerer, K., Tengblad, O., Weick, H., Zhukov, M. V., Johansson, H. T., Aksyutina, Yu., Aumann, T., Boretzky, K., Borge, M. J. G., Chatillon, A., Chulkov, L. V., Cortina-Gil, D., Pramanik, U. Datta, Emling, H., Forssén, C., Fynbo, H. O. U., Geissel, H., Ickert, G., Jonson, B., Kulessa, R., Langer, C., Lantz, Mattias, LeBleis, T., Mahata, K., Meister, M., Münzenberg, G., Nilsson, T., Nyman, G., Palit, R., Paschalis, S., Prokopowicz, W., Reifarth, R., Richter, A., Riisager, K., Schrieder, G., Shulgina, N. B., Simon, H., Sümmerer, K., Tengblad, O., Weick, H., and Zhukov, M. V.

Abstract

The very exotic nuclear resonance systems, 10He and 13Li, are produced in proton-knockout reactions from relativistic beams of 11Li and 14Be. The experimentally determined energy and angular correlations between their decay products, and , are analyzed using an expansion of decay amplitudes in a restricted set of hyperspherical harmonics. By considering only a small number of terms it is possible to extract the expansion coefficients directly from the experimental three-body correlations. This provides a model-independent way of getting information about the decay process, on the structure of the decaying nucleus and on the quantum characteristics of the binary subsystems. The results show that the relative-energy spectrum can be interpreted as consisting of two resonances, an Iπ=0+ ground state and an excited Iπ=2+ state. The relative-energy spectrum is interpreted as an Iπ=3/2− ground state overlapping with excited states having a structure similar to the 2+ state in 10He but spread over several states due to the coupling to the Iπ=3/2− core. The13Li data also give evidence for a contribution of a configuration where the two neutrons occupy the d-shell.

Published
2010
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28. Longitudinal momentum distributions of C-16,C-18 fragments after one-neutron removal from C-17,C-19

Author

Baumann, T., García Borge, María José, Geissel, H., Lenske, H., Markenroth, K., Schwab, W., Smedberg, M. H., Aumann, T., Axelsson, L., Bergmann, U., Cortina-Gil, D., Fraile, Luis M., Hellström, M., Ivanov, M., Iwasa, N., Janik, R., Jonson, B., Münzenberg, G., Nickel, F., Nilsson, T., Ozawa, A., Richter, A., Riisager, K., Scheidenberger, C., Schrieder, G., Simon, H., Sitar, B., Strmen, P., Sümmerer, K., Suzuki, T., Winkler, M., Wollnik, H., and Zhukov, M. V.

Subjects
Breakup reactions, 6 ≤ A ≤ 19 [[PACS] Properties of specific nuclei listed by mass ranges], [PACS] Properties of specific nuclei listed by mass ranges:6 ≤ A ≤ 19, [PACS] Projectile and target fragmentation, Nuclear structure, Momentum distributions, [PACS] Breakup and momentum distributions, Unstable nuclei
Abstract

6 pages, 5 figures.-- PACS nrs.: 25.60.Gc; 25.70.Mn; 27.20.+n.-- ArXiv pre-print available at: http://arxiv.org/abs/nucl-ex/9810011, The fragment separator FRS at GSI was used as an energy-loss spectrometer to measure the longitudinal momentum distributions of C-16,C-18 fragments after one-neutron removal reactions in C-17,C-19 impinging on a carbon target at about 910 MeV/u. The distributions in the projectile frames are characterized by a FWHM of 141 ± 6 MeV/c for C-16 and 69 ± 3 MeV/c for C-18. The results are compared with experimental data obtained at lower energies and discussed within existing theoretical models., This work was supported by the German Federal Minister for Education and Research (BMBF) under Contracts 06 DA 820, 06 OF 474, and 06 MZ 476 and by GSI via Hochschulzusammenarbeitsvereinbarungen under Contracts DARIK, OF ELK, and MZ KRK. It was partly supported by the Polish Committee of Scientific Research under Contract PB2rP03Br113r09, EC under Contract ERBCHGE-CT92-0003, CICYT under Contract AEN92-0788-C02-02 MJGB., and by Deutsche Forschungsgemeinschaft(DFG)under Contract 436 RUS 130r127r1. One of us(B.J.) acknowledges the support through an Alexander von Humboldt Research Award.

Published
1998

29. Erratum to 'Beta decay of Ar-31'

Author

Axelsson, L., Äystö, Juha, García Borge, María José, Fraile, Luis M., Fynbo, H.O.U., Honkanen, A., Hornshøj, P., Jokinen, A., Jonson, B., Lipas, P. O., Martel, Ismael, Mukha, I., Nilsson, T., Nyman, G., Petersen, B., Riisager, K., Smedberg, M. H., and Tengblad, Olof

Abstract

1 page.-- PACS nrs.: 23.40.−s; 27.30.+t; 29.30.Ep; 29.30.Kv; 21.60.Cs.-- Original article published in Nuclear Physics A 634(4): 475-496 (1998), available at: https://digital.csic.es/handle/10261/10063

Published
1998

30. Beta decay of Ar-31

Author

Axelsson, L., Äystö, Juha, García Borge, María José, Fraile, Luis M., Fynbo, H. O. U., Honkanen, A., Hornshøj, P., Jokinen, A., Jonson, B., Lipas, P. O., Martel, Ismael, Mukha, I., Nilsson, T., Nyman, G., Petersen, B., Riisager, K., Smedberg, M. H., and Tengblad, Olof

Subjects
Measured βp, β2p, βγ, E-p, I-p, Isospin mixing, Deduced Ex(Cl-31), Ne-17, OXBASH shell-model calculations, Radioactivity Ar-31 (from 1 GeV p on CaO powder target, selective mass separation), log ft, Gamow-Teller strength, Gamow-Teller quenching
Abstract

22 pages, 6 figures.-- PACS nrs.: 23.40.−s; 27.30.+t; 29.30.Ep; 29.30.Kv; 21.60.Cs. Erratum to this paper published on Oct 1998 in Nuclear Physics A 641(4): 529 (1998), available at: https://digital.csic.es/handle/10261/12171 A complete study of Ar-31 beta decay has been made by high-resolution charged-particle and gamma-ray spectroscopy. Beta-delayed radiation was detected by an array of three charged-particle detectors and a large-volume germanium detector. Fifteen new energy levels were discovered in Cl-31. The beta-strength distribution, measured to 14.5 MeV, is compared with a shell-model calculation in the full sd space. The quenching of the Gamow-Teller strength and the isospin impurity of the IAS in Cl-31 are discussed. This work was supported in part by CICYT under contract number AEN94-0833-C02-02 and by the Academy of Finland, project number 2854.

Published
1998
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31. Invariant-mass spectroscopy of Li-10 and Li-11

Author

Zinser, M., Humbert, F., Nilsson, T., Schwab, W., Simon, H., Aumann, T., García Borge, María José, Chulkov, L. V., Cub, J., Elze, Th. W., Emling, H., Geissel, H., Guillemaud-Mueller, D., Holzmann, R., Irnich, H., Jonson, B., Kratz, J. V., Kulessa, R., Leifels, Y., Lenske, H., Magel, A., Mueller, A. C., Münzenberg, G., Nickel, F., Nyman, G., Richter, Achim W., Riisager, K., Scheidenberger, C., Schrieder, G., Stelzer, K., Stroth, J., Surowiec, A., Tengblad, Olof, Wajda, E., and Zude, E.

Subjects
Breakup σ, Li-11, Li-10 deduced resonances, [PACS] Coulomb excitation, 6 ≤ A ≤ 19 [[PACS] Properties of specific nuclei listed by mass ranges], [PACS] Properties of specific nuclei listed by mass ranges:6 ≤ A ≤ 19, Decay features, [PACS] Projectile and target fragmentation, Nuclear Reactions C, Pb(Li-11,xn), E=280 MeV/nucleon, Measured neutron multiplicity, γ-decay associated sum-rule strengths
Abstract

26 pages, 5 tables, 10 figures.-- PACS nrs.: 25.60.+v; 27.20.+n; 25.70.Mn; 25.70.De., Break-up of secondary Li-11 ion beams (280 MeV/nucleon) on C and Pb targets into Li-9 and neutrons is studied experimentally. Cross sections and neutron multiplicity distributions are obtained, characterizing different reaction mechanisms. Invariant-mass spectroscopy for Li-11 and Li-10 is performed. The E1 strength distribution, deduced from electromagnetic excitation of Li-11 up to an excitation energy of 4 MeV comprises ~8% of the Thomas-Reiche-Kuhn energy-weighted sumrule strength. Two low-lying resonance-like structures are observed for Li-10 at decay energies of 0.21(5) and 0.62(10) MeV, the former one carrying 26(10)% of the strength and likely to be associated with an s-wave neutron decay. A strong di-neutron correlation in Li-11 can be discarded. Calculations in a quasi-particle RPA approach are compared with the experimental results for Li-10 and Li-11., The authors are indebted to the staff personel of the GSI accelerator group and of the target laboratory for their support. We acknowledge support by the German Federal Minister for Research and Technology (BMBF) under Contracts 06DA 665 I, 06OF 112 and 06MZ 465, by GSI under Contracts DA RIK, OF ELZ, MZ KRK, by the Polish Committee of Scientific Research under Contract PBZ/PB03 / 113/09, EC under contract ERBCHGE-CT92-0003 and by the Spanish CICYT under contract AEN92-0788-C02-02(MJGB).

Published
1997

32. Three-body correlations in electromagnetic dissociation of Borromean nuclei: The He-6 case

Author

Chulkov, L. V., Simon, H., Thompson, I. J., Aumann, T., García Borge, María José, Elze, Th. W., Emling, H., Geissel, H., Grigorenko, L. V., Hellström, M., Jonson, B., Kratz, J. W. V., Kulessa, R., Markenroth, K., Meister, M., Münzenberg, G., Nickel, F., Nilsson, T., Nyman, G., Pribora, V., Richter, Achim W., Riisager, K., Scheidenberger, C., Schrieder, G., Tengblad, Olof, Zhukov, M. V., Chulkov, L. V., Simon, H., Thompson, I. J., Aumann, T., García Borge, María José, Elze, Th. W., Emling, H., Geissel, H., Grigorenko, L. V., Hellström, M., Jonson, B., Kratz, J. W. V., Kulessa, R., Markenroth, K., Meister, M., Münzenberg, G., Nickel, F., Nilsson, T., Nyman, G., Pribora, V., Richter, Achim W., Riisager, K., Scheidenberger, C., Schrieder, G., Tengblad, Olof, and Zhukov, M. V.

Abstract

Dissociation of He-6 on a lead target has been studied at 240 MeV/u. The four-momenta of the two neutrons in coincidence with alpha-particles have been measured and used to reconstruct the three-body energy and angular correlations in the final state. For the first time, three-body correlations were included in the analysis of the He-6 dissociation data, and compared with calculations assuming a dipole mode for the electromagnetic dissociation. In addition, the experimental data have been analyzed using a series expansion of the final transition amplitude into hyperspherical functions, showing the importance of both nn and alpha n final-state interactions. It is shown that the dissociation process is governed by a transition of one neutron from the p-shell in the 6He ground state to the s-shell in the continuum further indicating that the role of the transition through an intermediate He-5(3/2(-)) state is more important than expected.

Published
2005

33. Experimental investigation of the Li-9 +d reaction at REX-ISOLDE

Author

Jeppesen, H., Ames, F., Bergmann, U. C., García Borge, María José, Cederkäll, J., Emhofer, S., Fraile, Luis M., Fynbo, H.O.U., Henry, S., Johansson, H.T., Jonson, B., Meister, M., Nilsson, T., Nyman, G., Pantea, M., Riisager, K., Richter, Achim W., Rudolph, K., Schrieder, G., Siebert, T., Tengblad, Olof, Tengborn, E., Turrión, Manuela, Hahn, R. von, Wenander, F., Wolf, B., Jeppesen, H., Ames, F., Bergmann, U. C., García Borge, María José, Cederkäll, J., Emhofer, S., Fraile, Luis M., Fynbo, H.O.U., Henry, S., Johansson, H.T., Jonson, B., Meister, M., Nilsson, T., Nyman, G., Pantea, M., Riisager, K., Richter, Achim W., Rudolph, K., Schrieder, G., Siebert, T., Tengblad, Olof, Tengborn, E., Turrión, Manuela, Hahn, R. von, Wenander, F., and Wolf, B.

Abstract

The particle unbound nucleus Li-10 has been investigated at the newly constructed post-accelerator REX-ISOLDE at CERN via the Li-9 +d --> Li-10 +p reaction at 2.36 MeV/u. We present here the preliminary analysis of our first data from REX-ISOLDE.

Published
2004

34. Two- and three-body correlations: breakup of halo nuclei

Author

Simon, H., Aumann, T., García Borge, María José, Chulkov, L. V., Elze, Th. W., Emling, H., Forssén, C., Geissel, H., Hellström, M., Jonson, B., Kratz, J. V., Kulessa, R., Leifels, Y., Markenroth, K., Meister, M., Münzenberg, G., Nickel, F., Nilsson, T., Nyman, G., Pribora, V., Richter, A., Riisager, K., Scheidenberger, C., Schrieder, G., Tengblad, Olof, Zhukov, M. V., Simon, H., Aumann, T., García Borge, María José, Chulkov, L. V., Elze, Th. W., Emling, H., Forssén, C., Geissel, H., Hellström, M., Jonson, B., Kratz, J. V., Kulessa, R., Leifels, Y., Markenroth, K., Meister, M., Münzenberg, G., Nickel, F., Nilsson, T., Nyman, G., Pribora, V., Richter, A., Riisager, K., Scheidenberger, C., Schrieder, G., Tengblad, Olof, and Zhukov, M. V.

Abstract

Nuclear knockout, reactions at relativistic provide a sensitive tool to determine the ground state properties of nuclei close to the drip line. Studies with kinematically complete measurements reveal the, initial correlations in the reacting systems and yield spectroscopic information on the continuum states populated in the decay channel. The coincident data of charged fragments and neutrons as well allows to unveil the possible influence of the reaction mechanism to the interpretation of the measurements. Two- and three-body correlations can be observed and allow to determine the internal momentum distributions of halo nuclei as well as the assignment of Spills and parities to the populated states in the intermediate systems in the breakup process.

Published
2004

35. Dissociation of 8He into 6He + n + X at 240 MeV/u

Author

Nilsson, T., Humbert, F., Schwab, W., Zinser, M., Blaich, Th., García Borge, María José, Chulkov, L. V., Eickhoff, H., Elze, Th. W., Emling, H., Franzke, B., Freiesleben, H., Geissel, H., Grimm, K., Guillemaud-Mueller, D., Hansen, P. G., Holzmann, R., Irnich, H., Johannsen, L., Jonson, B., Keller, J. G., Klepper, O., Klingler, H., Kratz, J. V., Kulessa, R., Lambrecht, D., Leifels, Y., Magel, A., Mohar, M., Moore, E. F., Mueller, A. C., Münzenberg, G., M¢ller, P., Nickel, F., Nyman, G., Richter, Achim W., Riisager, K., Scheidenberger, C., Schrieder, G., Sherrill, B. M., Simon, H., Stelzer, K., Stroth, J., Tengblad, Olof, Trautmann, W., Wajda, E., Zude, E., and S034-Collaboration

Subjects
Physics, Nuclear and High Energy Physics, Physical chemistry, Dissociation (chemistry)
Abstract

4 pages, 3 figures, 2 tables., Extremely neutron-rich nuclei exhibit a number of interesting features of which the most well-known is the neutron halo phenomenon found in 11Li. See e.g. ref. [1] for a recent review. A much less investigated nucleus is 8He, although it is the nucleus with the highest A/Z-ratio that is still stable against particle emission. In the first experiment where evidence for an anomalously large matter radius in 11Li was seen [2], similar effects were also found in 6He and 8He. The extended neutron distribution has previously mainly been probed in dissociation experiments [3] at 800 MeV/u. We present here further information on reactions involving 8He.

Published
1995

36. Implications on obtained data, electronics and DAQ-system by the use of dense detector setups in beta-decay studies

Author

Tengblad, Olof, García Borge, María José, Fraile, Luis M., Bergmann, U. C., Fynbo, H.O.U., Riisager, K., Jonson, B., Nilsson, T., Nyman, G., Wenander, F., IS339 Collaboration, IS361 Collaboration, ISOLDE Collaboration, Tengblad, Olof, García Borge, María José, Fraile, Luis M., Bergmann, U. C., Fynbo, H.O.U., Riisager, K., Jonson, B., Nilsson, T., Nyman, G., Wenander, F., IS339 Collaboration, IS361 Collaboration, and ISOLDE Collaboration

Abstract

Beta-decay investigations of light nuclei close to the drip lines have revealed new and intriguing features of nuclear structure. However, to fully investigate the decay pattern of these nuclei, new detector systems with an increased granularity have to be implemented. The use of segmented detectors as, for example, the Double-Sided Silicon Strip Detectors has thus proven to give fantastic improvements on the quality of the obtained data. The extra granularity allows for discrimination between sequentially or directly emitted charged particles and thus to follow decay patterns of delayed particle emission.

Published
2002

37. Light exotic isotopes: recent beam developments and physics applications at ISOLDE

Author

Bergmann, U. C., Axelsson, L., Bennett, J. R. C., García Borge, María José, Catherall, R., Drumm, P. V., Fedoseyev, V. N., Forssén, C., Fraile, Luis M., Fynbo, H.O.U., Georg, U., Giles, T., Grévy, S., Hornshøj, P., Jonson, B., Jonsson, O. C., Köster, U., Lettry, J., Markenroth, K., Marqués, F. M., Mishin, V. I., Mukha, I., Nilsson, T., Nyman, G., Oberstedt, A., Ravn, H. L., Riisager, K., Schrieder, G., Sebastian, V., Simon, H., Tengblad, Olof, Wenander, F., Wilhelmsen Rolander, K., Bergmann, U. C., Axelsson, L., Bennett, J. R. C., García Borge, María José, Catherall, R., Drumm, P. V., Fedoseyev, V. N., Forssén, C., Fraile, Luis M., Fynbo, H.O.U., Georg, U., Giles, T., Grévy, S., Hornshøj, P., Jonson, B., Jonsson, O. C., Köster, U., Lettry, J., Markenroth, K., Marqués, F. M., Mishin, V. I., Mukha, I., Nilsson, T., Nyman, G., Oberstedt, A., Ravn, H. L., Riisager, K., Schrieder, G., Sebastian, V., Simon, H., Tengblad, Olof, Wenander, F., and Wilhelmsen Rolander, K.

Abstract

This paper is divided in three parts: (i) the measurement of yields and decay losses of Li and Be isotopes released from a thin foil tantalum target at the CERN/ISOLDE PS-Booster; (ii) results from beta-decay experiments on Be-12 and Be-14, an improved half-life of 21.49(3) ms has been obtained for Be-12; (iii) the beta-decay of C-9. An outline of the analysis procedure to determine the branching at high excitation energies is given. The ground-state branch has been determined to 54.1(15)%.

Published
2002

38. Two-proton emission in the decay of Ar-31

Author

Axelsson, L., Äystö, Juha, Bergmann, U. C., García Borge, María José, Fraile, Luis M., Fynbo, H.O.U., Honkanen, A., Hornshøj, P., Jokinen, A., Jonson, B., Martel, Ismael, Mukha, I., Nilsson, T., Nyman, G., Petersen, B., Riisager, K., Smedberg, M. H., Tengblad, Olof, Axelsson, L., Äystö, Juha, Bergmann, U. C., García Borge, María José, Fraile, Luis M., Fynbo, H.O.U., Honkanen, A., Hornshøj, P., Jokinen, A., Jonson, B., Martel, Ismael, Mukha, I., Nilsson, T., Nyman, G., Petersen, B., Riisager, K., Smedberg, M. H., and Tengblad, Olof

Abstract

Several beta-delayed two-proton branches were observed in the decay of Ar-31, the most intense ones proceeding through the isobaric analogue state (IAS) in Cl-31. The mechanism of the two-proton emission is studied via the energy and angular distributions of the two protons, Simultaneous emission of the two protons fits the present data well, sequential decays might also describe them. Independent of the decay mechanism, a spin of 5/2 for the IAS is suggested, An improved limit on the direct two-proton emission from the ground state of Ar-31 is presented.

Published
1998

39. Fine structure in the beta-delayed proton decay of Ar-33

Author

Honkanen, A., Axelsson, L., Äystö, Juha, García Borge, María José, Jonson, B., Jokinen, A., Martel, Ismael, Martínez Pinedo, Gabriel, Mukha, I., Nilsson, T., Nyman, G., Petersen, B., Poves, Alfredo, Smedberg, M. H., Teijeiro, A., Tengblad, Olof, Honkanen, A., Axelsson, L., Äystö, Juha, García Borge, María José, Jonson, B., Jokinen, A., Martel, Ismael, Martínez Pinedo, Gabriel, Mukha, I., Nilsson, T., Nyman, G., Petersen, B., Poves, Alfredo, Smedberg, M. H., Teijeiro, A., and Tengblad, Olof

Abstract

Low-energy beta-delayed protons from Ar-33 have been measured for the first time. The data reveal states, which, despite unfavourable barrier penetrability values, strongly decay to the first excited 2+ state in S-32. The observation is discussed in terms of the standard shell model. A natural explanation is provided by the large spectroscopic amplitudes, involving s(1/2) and d(3/2) orbitals, as well as the l = 0 barrier penetrability, favouring the decay to the 2+ state.

Published
1996

40. Beta-decay to the proton halo state in 17F

Author

García Borge, María José, Deding, J., Hansen, P. G., Jonson, B., Martínez Pinedo, Gabriel, Møller, P., Nyman, G., Poves, Alfredo, Richter, Achim W., Riisager, K., Tengblad, Olof, ISOLDE Collaboration, García Borge, María José, Deding, J., Hansen, P. G., Jonson, B., Martínez Pinedo, Gabriel, Møller, P., Nyman, G., Poves, Alfredo, Richter, Achim W., Riisager, K., Tengblad, Olof, and ISOLDE Collaboration

Abstract

In the first experiment at the newly constructed ISOLDE Facility the first-forbidden beta-decay of 17Ne into the first excited state of 17F has been measured. It is a factor two faster than the corresponding mirror decay and thus gives one of the largest recorded asymmetries for beta decays feeding bound final states. Shell-model calculations can only reproduce the asymmetry if the halo structure of the 17F state is taken into account.

Published
1993

41. First observation of beta-delayed deuteron emission

Author

Riisager, K., García Borge, María José, Gabelmann, H., Hansen, P. G., Johannsen, L., Jonson, B., Kurcewicz, W., Nyman, G., Richter, Achim W., Tengblad, Olof, Wilhelmsen, K., Riisager, K., García Borge, María José, Gabelmann, H., Hansen, P. G., Johannsen, L., Jonson, B., Kurcewicz, W., Nyman, G., Richter, Achim W., Tengblad, Olof, and Wilhelmsen, K.

Abstract

Beta-delayed deuteron emission has been observed in the decay of He-6 with a branching ratio of (2.8 ± 0.5)×10−6. Simple theoretical estimates predict an intensity that is significantly higher.

Published
1990

42. The doubly closed shell nucleus Sn-132(50)82

Author

Björnstad, T., García Borge, María José, Blomqvist, J., Von Dincklage, R. D., Ewan, G. T., Hoff, P., Jonson, B., Kawade, K., Kerek, A., Klepper, O., Lövhöiden, G., Mattsson, S., Nyman, G., Ravn, H. L., Rudstam, G., Sistemich, K., and Tengblad, Olof

Subjects
Radioactivity In-132 (β-) [from U(p,fission)]: measured Eγ, Iγ, Ee, Ie, En, T1/2,Qβ, γγ-, βγ-coin, Sn-132 deduced level scheme, B(E2), neutron separation energy, ICC, On-line mass separation, measured Eγ, Iγ, Ee, Ie, En, T1/2,Qβ, γγ-, βγ-coin [Radioactivity In-132 (β-) [from U(p,fission)]], Uranium carbide target, Ge(Li), Si(Li), He-3 ion chamber, plastic scintillator telescope detectors
Abstract

23 pages, 4 tables, 10 figures., The structure of excited states in Sn-132, fed in the β-decay of In-132, has been investigated. Absolute intensities were deduced from γ-singles measurements. From multi-spectrum analysis of γ-lines the half-life of In-132 was determined to be 186 ± 22 ms. A level scheme based on γγ and βγ coincidences is presented. The conversion electron spectrum has been studied and internal conversion coefficients deduced for two low-energy transitions. The total decay energy of In-132 was determined, from γ-gated β-spectra, to be Q(β) = 13.6 ± 0.4 MeV. A lower limit of 6.968 MeV for the neutron separation energy in Sn-132 was deduced from the β-delayed neutron spectrum. The experimental results on the level structure of the doubly closed shell nucleus Sn-132 show that the shell model is applicable even far from the valley of stability.

Published
1986

43. An appropriate inspiratory flow pattern can enhance CO2 exchange, facilitating protective ventilation of healthy lungs.

Author

Sturesson LW, Malmkvist G, Allvin S, Collryd M, Bodelsson M, and Jonson B

Subjects
Acute Lung Injury metabolism, Acute Lung Injury physiopathology, Adult, Aged, Algorithms, Anesthesia, Breath Tests, Capnography, Carbon Dioxide analysis, Female, Humans, Intermittent Positive-Pressure Breathing, Male, Middle Aged, Pulmonary Alveoli physiopathology, Pulmonary Gas Exchange, Respiratory Dead Space, Tidal Volume, Carbon Dioxide metabolism, Pulmonary Ventilation, Respiration, Artificial methods
Abstract

Background: In acute lung injury, CO2 exchange is enhanced by prolonging the volume-weighted mean time for fresh gas to mix with resident alveolar gas, denoted mean distribution time (MDT), and by increasing the flow rate immediately before inspiratory flow interruption, end-inspiratory flow (EIF). The objective was to study these effects in human subjects without lung disease and to analyse the results with respect to lung-protective ventilation of healthy lungs., Methods: During preparation for intracranial surgery, the lungs of eight subjects were ventilated with a computer-controlled ventilator, allowing breath-by-breath modification of the inspiratory flow pattern. The durations of inspiration (TI) and postinspiratory pause (TP) were modified, as was the profile of the inspiratory flow wave (i.e. constant, increasing, or decreasing). The single-breath test for CO2 was used to quantify airway dead space (VDaw) and CO2 exchange., Results: A long MDT and a high EIF augment CO2 elimination by reducing VDaw and promoting mixing of tidal gas with resident alveolar gas. A heat and moisture exchanger had no other effect than enlarging VDaw. A change of TI from 33 to 15% and of TP from 10 to 28%, leaving the time for expiration unchanged, would augment tidal elimination of CO2 by 14%, allowing a 10% lower tidal volume., Conclusions: In anaesthetized human subjects without lung disease, CO2 exchange is enhanced by a long MDT and a high EIF. A short TI and a long TP allow significant reduction of tidal volume when lung-protective ventilation is required., Clinical Trial Registration: NCT01686984., (© The Author 2016. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Published
2016
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44. Anaesthetic conserving device AnaConDa: dead space effect and significance for lung protective ventilation.

Author

Sturesson LW, Bodelsson M, Jonson B, and Malmkvist G

Subjects
Adult, Aged, Aged, 80 and over, Carbon Dioxide analysis, Equipment Design, Female, Humans, Male, Methyl Ethers administration & dosage, Middle Aged, Postoperative Care methods, Pulmonary Gas Exchange drug effects, Sevoflurane, Tidal Volume drug effects, Anesthesia, Inhalation instrumentation, Anesthesia, Inhalation methods, Anesthetics, Inhalation administration & dosage, Respiration, Artificial methods, Respiratory Dead Space drug effects
Abstract

Background: The anaesthetic conserving device AnaConDa (ACD) reflects exhaled anaesthetic agents thereby facilitating the use of inhaled anaesthetic agents outside operating theatres. Expired CO₂ is, however, also reflected causing a dead space effect in excess of the ACD internal volume. CO₂ reflection from the ACD is attenuated by humidity. This study tests the hypothesis that sevoflurane further attenuates reflection of CO₂. An analysis of clinical implications of our findings was performed., Methods: Twelve postoperative patients received mechanical ventilation using a conventional heat and moisture exchanger (HME, internal volume 50 ml) and an ACD (100 ml), the latter with or without administration of sevoflurane. The ACD was also studied with a test lung at high sevoflurane concentrations. Reflection of CO₂ and dead space effects were evaluated with the single-breath test for CO2., Results: Sevoflurane reduced but did not abolish CO₂ reflection. In patients, the mean dead space effect with 0.8% sevoflurane was 88 ml larger using the ACD compared with the HME (P<0.001), of which 38 ml was due to CO₂ reflection. Our calculations show that with the use of the ACD, normocapnia cannot be achieved with tidal volume <6 ml kg(-1) even when respiratory rate is increased., Conclusions: An ACD causes a dead space effect larger than its internal volume due to reflection of CO₂, which is attenuated but not abolished by sevoflurane administration. CO₂ reflection from the ACD limits its use with low tidal volume ventilation, such as with lung protection ventilation strategies., Clinical Trial Registration: Clinical Trials NCT01699802., (© The Author [2014]. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Published
2014
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45. Protective ventilation in experimental acute respiratory distress syndrome after ventilator-induced lung injury: a randomized controlled trial.

Author

Uttman L, Bitzén U, De Robertis E, Enoksson J, Johansson L, and Jonson B

Subjects
Acute Lung Injury pathology, Animals, Blood Gas Analysis, Computer Simulation, Endpoint Determination, Hemodynamics physiology, Lung pathology, Monitoring, Intraoperative, Pulmonary Gas Exchange physiology, Respiratory Distress Syndrome pathology, Respiratory Mechanics physiology, Swine, Acute Lung Injury therapy, Pneumonia, Ventilator-Associated therapy, Respiration, Artificial, Respiratory Distress Syndrome therapy
Abstract

Background: Low tidal volume (V(T)), PEEP, and low plateau pressure (P(PLAT)) are lung protective during acute respiratory distress syndrome (ARDS). This study tested the hypothesis that the aspiration of dead space (ASPIDS) together with computer simulation can help maintain gas exchange at these settings, thus promoting protection of the lungs., Methods: ARDS was induced in pigs using surfactant perturbation plus an injurious ventilation strategy. One group then underwent 24 h protective ventilation, while control groups were ventilated using a conventional ventilation strategy at either high or low pressure. Pressure-volume curves (P(el)/V), blood gases, and haemodynamics were studied at 0, 4, 8, 16, and 24 h after the induction of ARDS and lung histology was evaluated., Results: The P(el)/V curves showed improvements in the protective strategy group and deterioration in both control groups. In the protective group, when respiratory rate (RR) was ≈ 60 bpm, better oxygenation and reduced shunt were found. Histological damage was significantly more severe in the high-pressure group. There were no differences in venous oxygen saturation and pulmonary vascular resistance between the groups., Conclusions: The protective ventilation strategy of adequate pH or PaCO2 with minimal V(T), and high/safe P(PLAT) resulting in high PEEP was based on the avoidance of known lung-damaging phenomena. The approach is based upon the optimization of V(T), RR, PEEP, I/E, and dead space. This study does not lend itself to conclusions about the independent role of each of these features. However, dead space reduction is fundamental for achieving minimal V(T) at high RR. Classical physiology is applicable at high RR. Computer simulation optimizes ventilation and limiting of dead space using ASPIDS. Inspiratory P(el)/V curves recorded from PEEP or, even better, expiratory P(el)/V curves allow monitoring in ARDS.

Published
2012
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46. Carbon dioxide rebreathing with the anaesthetic conserving device, AnaConDa®.

Author

Sturesson LW, Malmkvist G, Bodelsson M, Niklason L, and Jonson B

Subjects
Anesthetics, Inhalation administration & dosage, Gas Scavengers, Humans, Inhalation physiology, Models, Anatomic, Respiratory Dead Space physiology, Respiratory Rate physiology, Tidal Volume physiology, Anesthesia, Inhalation instrumentation, Carbon Dioxide analysis
Abstract

Background: The anaesthetic conserving device (ACD) AnaConDa(®) was developed to allow the reduced use of inhaled agents by conserving exhaled agent and allowing rebreathing. Elevated has been observed in patients when using this ACD, despite tidal volume compensation for the larger apparatus dead space. The aim of the present study was to determine whether CO(2), like inhaled anaesthetics, adsorbs to the ACD during expiration and returns to a test lung during the following inspiration., Methods: The ACD was attached to an experimental test lung. Apparent dead space by the single-breath test for CO(2) and the amount of CO(2) adsorbed to the carbon filter of the ACD was measured with infrared spectrometry., Results: Apparent dead space was 230 ml larger using the ACD compared with a conventional heat and moisture exchanger (internal volumes 100 and 50 ml, respectively). Varying CO(2) flux to the test lung (85-375 ml min(-1)) did not change the measured dead space nor did varying respiratory rate (12-24 bpm). The ACD contained 3.3 times more CO(2) than the predicted amount present in its internal volume of 100 ml., Conclusions: Our measurements show a CO(2) reservoir effect of 180 ml in excess of the ACD internal volume. This is due to adsorption of CO(2) in the ACD during expiration and return of CO(2) during the following inspiration.

Published
2012
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47. Element migration from glass compositions containing no added lead.

Author

Hynes MJ, Forde S, and Jonson B

Subjects
Acetic Acid, Beverages, Kinetics, Consumer Product Safety standards, Glass analysis, Glass chemistry, Metals, Heavy analysis
Abstract

Six crystal glass compositions without added lead were used to prepare standard beakers having a volume of ca. 240 ml. The experimentally determined concentrations of the elements in the glass beakers were in satisfactory agreement with the theoretically predicted values. The degree of leaching of selected elements from these beakers was determined using 4% acetic acid as described in the ISO 7086-1:2000 standard test. In addition, to the degree of leaching by 4% acetic acid, migration into cola, red wine, 40% ethanol and 0.3% citric acid was also determined. Elements tested included antimony, barium, bismuth and zinc as these were considered to be of most interest. The results show that it is possible to produce durable glass containing no added lead. The overall quality of the glasses was good and the concentrations of the various elements migrating (leaching) into the various test solutions used was very small and it is clear that they would not present a hazard to consumers in the event that they were to use glasses of any of these compositions for consumption of either alcoholic or non-alcoholic beverages. The original ISO7086-1:2000 test using a 4% acetic acid leaching solution was developed to test for lead migration from crystal containing added lead and ceramic ware containing lead glazes or colouring. This work also shows that it is an excellent leaching agent for assessing the safety of crystal containing no added lead as it gave the highest degree of migration for all the glass compositions and all the elements tested. In the case of glasses containing ZnO, it was shown that the degree of zinc migration was linearly related to the mole-% of ZnO in the glass. With respect to the durability of glasses, it was shown that the degree of attack increases when the degree of silica depolymerisation increases.

Published
2004
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48. Kinetics of lung clearance of 99mTc-DTPA in smoking patients with sarcoidosis compared to healthy smokers.

Author

Brådvik I, Wollmer P, Evander E, Lárusdóttir H, Blom-Bülow B, and Jonson B

Subjects
Adult, Follow-Up Studies, Forced Expiratory Volume, Half-Life, Humans, Middle Aged, Sarcoidosis, Pulmonary physiopathology, Smoking physiopathology, Spirometry, Vital Capacity, Lung metabolism, Radiopharmaceuticals pharmacokinetics, Sarcoidosis, Pulmonary metabolism, Smoking metabolism, Technetium Tc 99m Pentetate pharmacokinetics
Abstract

Investigation of lung clearance of 99mTc-labelled diethylene triamine penta-acetic acid (DTPA) in smoking sarcoid patients has been impeded by difficulties to differ between pathology of clearance kinetics caused by sarcoidosis and by smoking. This study explores the kinetics of lung clearance of 99mTc-DTPA in 15 current smokers with intrathoracic sarcoidosis. The results are compared with findings from 16 healthy smokers. Measurements of lung clearance over 180 min, i.e. longer than usual, revealed in II of the sarcoid patients a bi-exponential lung clearance course, which is pathologic. All healthy smokers also showed a bi-exponential lung clearance. In the analysis of the bi-exponential curve an initial fast, and a slow clearance component could be separated. The smokers with sarcoidosis had a significantly higher elimination rate of the slow component than the healthy smokers. Thus, analysis of the late part of the lung clearance curve may be rewarding in smoking sarcoid patients. The study shows that lung clearance of 99mTc-DTPA may be a method useful also in smoking patients with sarcoidosis.

Published
2002
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49. Dynamics of carbon dioxide elimination following ventilator resetting.

Author

Taskar V, John J, Larsson A, Wetterberg T, and Jonson B

Subjects
Adult, Aged, Aged, 80 and over, Female, Humans, Male, Middle Aged, Postoperative Period, Tidal Volume, Carbon Dioxide, Pulmonary Gas Exchange, Respiration, Artificial
Abstract

Background: Carbon dioxide elimination (VCO2) at steady state corresponds to the metabolic rate. A change in tidal ventilation will lead to a transient response in VCO2 if other determinants of VCO2 are constant. This principle may be applied in the critical care unit to reset ventilators., Objective: To define and characterize the transient response of VCO2 to a well-defined change in ventilation., Methods: Forty-four patients in stable condition receiving volume-controlled mechanical ventilation had trend recordings of ventilator pressures, flow, volumes, VCO2, and end-tidal CO2 (ETCO2) for 20 min. At time t0, the minute ventilation was either increased (n = 22) or decreased (n = 22) by 10% after which these parameters were monitored over 30 min. Blood gas values were measured 5 and 20 min after the change in ventilation and the dead space fractions were computed using the single breath-CO2 test., Data Analysis: The first ten breaths (till t1) after a change in ventilation were excluded. The time constant (tau) of the relative change in VCO2 (delta VCO2) was calculated by fitting exponential regressions to delta VCO2 for periods up to 20 min after t1., Results: The delta VCO2 at t1 was proportional to the relative change in tidal volume (delta VT). The proportionality decreased gradually during 20 min. The proportionality of the relative change in ETCO2 (delta ETCO2) or PaCO2 (delta PaCO2) with delta VT was minimal at t1 and increased during the 20 min. tau increased progressively when calculated over longer periods (p < 0.001). tau was similar in the groups with increased and decreased ventilation up to 5 min, after which it was longer in the group with decreased ventilation (p < 0.05). The delta PaCO2 after 20 min correlated best with delta VCO2 at t1 (r = -0.8) and with delta ETCO2 at the end of 20 min (r = 0.8)., Conclusions: Noninvasively monitored VCO2 provides an instantaneous indication of the change in alveolar ventilation in well-sedated, mechanically ventilated patients in stable condition without significant cardiopulmonary disease.

Published
1995
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50. Lung mechanics and gas exchange during exercise in pulmonary sarcoidosis.

Author

Brådvik I, Wollmer P, Blom-Bülow B, Albrechtsson U, and Jonson B

Subjects
Adult, Aged, Airway Resistance, Female, Forced Expiratory Volume, Functional Residual Capacity, Humans, Lung Compliance, Male, Middle Aged, Oxygen blood, Residual Volume, Tidal Volume, Total Lung Capacity, Vital Capacity, Lung physiopathology, Lung Diseases physiopathology, Physical Exertion physiology, Pulmonary Gas Exchange physiology, Respiratory Mechanics physiology, Sarcoidosis physiopathology
Abstract

To clarify how lung function at exercise is affected in sarcoidosis, and to analyze how exercise studies compare to testing measurements, 63 patients with pulmonary sarcoidosis were examined with lung mechanics and arterial blood gases during exercise. These findings were compared with simultaneously obtained, but previously reported results of the static lung pressure/volume curve and the lung resistance/static lung pressure curve. While mechanical variables at maximal exercise were as sensitive as those determined by measuring the PstL/V and RL/PstL curves, mechanics during spontaneous breathing at rest was less sensitive. The derangement of mechanics was more evident than that of arterial blood gases. No measurement at rest was a good predictor of working capacity or of arterial PaO2. A comprehensive exercise examination may be an alternative to resting investigations, which are either more elaborate or less sensitive.

Published
1991
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