-
Guttormsen, Magne Sveen
(2019).
Mini-workshop on the beta-Oslo method.
-
Guttormsen, Magne Sveen
(2019).
Level density in Nd isotopes as function of deformation.
-
Guttormsen, Magne Sveen
(2019).
Nøytronets mørke side.
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Guttormsen, Magne Sveen
(2018).
The beta-Oslo method.
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Guttormsen, Magne Sveen; Larsen, Ann-Cecilie; Midtbø, Jørgen E.; Crespo Campo, Lucia; Görgen, Andreas & Ingeberg, Vetle Wegner
[Vis alle 11 forfattere av denne artikkelen]
(2017).
Gamma-widths, lifetimes and fluctuations in the nuclear quasi-continuum.
-
Guttormsen, Magne Sveen
(2017).
Gamma-widths, lifetimes and fluctuations in the nuclear quasi-continuum
.
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Guttormsen, Magne Sveen
(2017).
On the validity of the generalized Brink-Axel hypothesis.
-
Guttormsen, Magne Sveen
(2017).
The beta-Oslo method.
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Tveten, Gry Merete; Spyrou, Artemis; Schwengner, Ronald; Naqvi, Farheen; Larsen, Ann-Cecilie & Eriksen, Tomas Kvalheim
[Vis alle 22 forfattere av denne artikkelen]
(2016).
The Statistical Properties Of 92Mo And Implications For The p-process.
Vis sammendrag
A particularly challenging part of the question of how elements heavier than iron are created in extreme, astrophysical environments is the creation of the so-called p-nuclei, which are believed to be mainly produced in the O-Ne layer of type II supernovae or type Ia supernovae. The lack of needed nuclear data presents an obstacle in nailing down the precise site and astrophysical conditions for the production of these isotopes. Astrophysical model calculations are able to reproduce abundance patterns of most p-isotopes reasonably well, with some pivotal exceptions. In particular, p-isotopes of mass 92 ≤ A ≤ 98 are underproduced in calculations compared to the actual abundance of these isotopes. The p-isotope 92Mo represents one of the most severe cases of underproduction. State-of-the-art p-process calculations systematically underestimate the observed solar abundance of this isotope.
The main destruction mechanism of this isotope in the standard description of the p-process is through the 92Mo(γ, p)91Nb reaction. Measurements on the nuclear level density and average gamma strength function of 92Mo have been carried out at the Oslo Cyclotron Laboratory. TALYS cross section and reaction rate calculations where the experimental results are used as input will be presented. The data provide stringent constraints on the 91Nb(p, γ)92Mo (and consequently the inverse) reaction rate. The reaction rate extracted in this work was used in reaction network calculations for the scenario of a p-process taking place in a type II supernova explosion as the shock front passes through the O-Ne layer of a 25 solar mass star.
-
Guttormsen, Magne Sveen
(2016).
On the validity of the generalised Brink-Axel hypothesis.
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Guttormsen, Magne Sveen; Larsen, Ann-Cecilie; Görgen, Andreas; Renstrøm, Therese; Siem, Sunniva & Tornyi, Tamas Gabor
[Vis alle 7 forfattere av denne artikkelen]
(2016).
Is the generalized Brink-Axel hypothesis valid?
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Guttormsen, Magne Sveen
(2016).
On the validity of the Brink-Axel hypothesis.
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Guttormsen, Magne Sveen
(2016).
Nuclear structure in the quasi-continuum.
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Guttormsen, Magne Sveen
(2015).
Thermodynamic and electromagnetic properties of nuclei.
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Guttormsen, Magne Sveen
(2015).
Adam's Early Era at HMI, Berlin.
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Guttormsen, Magne Sveen
(2015).
Scissors resonances in the quasi-continuum of heavy nuclei.
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Guttormsen, Magne Sveen
(2015).
The standard Oslo method.
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Guttormsen, Magne Sveen
(2015).
My projects in CAN.
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Guttormsen, Magne Sveen
(2014).
Level density of atomic nuclei.
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Guttormsen, Magne Sveen
(2014).
Nuclear level densities from an experimental point of view.
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Tveten, Gry Merete; Campo, L.C.; Eriksen, Tomas Kvalheim; Giacoppo, Francesca; Guttormsen, Magne Sveen & Görgen, Andreas
[Vis alle 16 forfattere av denne artikkelen]
(2014).
The statistical properties of Sn-isotopes studied with the Oslo-method.
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Guttormsen, Magne Sveen
(2014).
Basics of the Oslo Method on the beta-stability line.
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Guttormsen, Magne Sveen
(2014).
Exploring the Nuclear Quasi-Continuum with the Oslo Method.
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Guttormsen, Magne Sveen
(2014).
The long and winding road of the Oslo Method.
-
Guttormsen, Magne Sveen
(2014).
Large Scissors Resonance Strength in Actinides.
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Guttormsen, Magne Sveen; Larsen, Ann-Cecilie; Blasi, N; Bracco, A; Camera, F & Eriksen, Tomas Kvalheim
[Vis alle 18 forfattere av denne artikkelen]
(2014).
Recent results using large LaBr3 detectors and future perspectives.
-
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Guttormsen, Magne Sveen
(2013).
Constant-temperature level densities and large scissors strength in the quasi- continuum of actinides.
-
Guttormsen, Magne Sveen
(2013).
Level densities and the scissors resonance in Th, Pa and U isotopes.
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Guttormsen, Magne Sveen
(2013).
The Oslo Method.
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Guttormsen, Magne Sveen
(2013).
Observation of large scissors strength in actinides.
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Guttormsen, Magne Sveen
(2013).
The Oslo method applied to the actinides.
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Guttormsen, Magne Sveen
(2013).
The Oslo Cyclotron Laboratory and level density and gamma-strength in the actinides.
-
Guttormsen, Magne Sveen
(2013).
Scissors mode in the actinides.
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Guttormsen, Magne Sveen; Bernstein, Lee; Bürger, Alexander; Görgen, Andreas; Gunsing, Frank & Hagen, Trine Wiborg
[Vis alle 10 forfattere av denne artikkelen]
(2012).
Observation of large orbital scissors strength in actinides.
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Larsen, Ann-Cecilie; Bürger, Alexander; Goriely, Stephane; Guttormsen, Magne Sveen; Görgen, Andreas & Harrisopulos, Sotirios
[Vis alle 12 forfattere av denne artikkelen]
(2012).
Astrophysical reaction rates and the low-energy enhancement in the γ-ray strength.
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Larsen, Ann-Cecilie; Bürger, Alexander; Goriely, Stephane; Guttormsen, Magne Sveen; Görgen, Andreas & Harrisopulos, Sotirios
[Vis alle 12 forfattere av denne artikkelen]
(2012).
LOW-ENERGY ENHANCEMENT IN THE γ STRENGTH WITH IMPACT ON ASTROPHYSICAL REACTION RATES.
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Guttormsen, Magne Sveen
(2012).
Large scissors strength in the quasi-continuum of actinides.
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Larsen, Ann-Cecilie; Bürger, Alexander; Eriksen, Tomas Kvalheim; Görgen, Andreas; Guttormsen, Magne Sveen & Hagen, Trine Wiborg
[Vis alle 28 forfattere av denne artikkelen]
(2011).
Experiments of reaction model inputs: level density and gamma strength.
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Larsen, Ann-Cecilie; Guttormsen, Magne Sveen; Bürger, Alexander; Eriksen, Tomas Kvalheim; Görgen, Andreas & Hagen, Trine Wiborg
[Vis alle 15 forfattere av denne artikkelen]
(2011).
Level density and gamma strength - achievements and challenges.
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Guttormsen, Magne Sveen; Larsen, Ann-Cecilie; Bürger, Alexander; Görgen, Andreas; Nyhus, Hilde-Therese & Siem, Sunniva
[Vis alle 9 forfattere av denne artikkelen]
(2011).
Do light nuclei display a universal gamma-ray strength function?
-
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Olsen, Dag Rune & Guttormsen, Magne Sveen
(2010).
Kreftbehandling og protonterapi.
[TV].
NRK Schrødingers katt.
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Bürger, Alexander; Görgen, Andreas; Guttormsen, Magne Sveen; Hagen, Trine Wiborg; Larsen, Ann-Cecilie & Mansouri, Pejman
[Vis alle 15 forfattere av denne artikkelen]
(2010).
Level Densities and Gamma-Ray Strength Functions in Zr Isotopes.
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Nyhus, Hilde-Therese; Siem, Sunniva; Guttormsen, Magne Sveen; Larsen, Ann-Cecilie; Syed, Naeem Ul Hasan & Voinov, Alexander
(2009).
Level densities and the gamma ray strength functions of 163;164Dy.
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Bürger, Alexander; Larsen, Ann-Cecilie; Syed, Naeem Ul Hasan; Guttormsen, Magne Sveen; Nyhus, Hilde-Therese & Siem, Sunniva
[Vis alle 16 forfattere av denne artikkelen]
(2009).
Level Densities and Gamma Strength Functions in Light Sc and Ti Isotopes.
Vis sammendrag
Level densities and γ-ray strength functions are an important input to stellar reaction models and isotope abundance calculations. The nuclear physics group at the Oslo Cyclotron Laboratory has developed a method to extract both the level density and the γ-ray strength function below the particle-emission thresholds from particle-γ coincidence
data obtained in proton- or 3 He-induced pickup or transfer reactions. This experimental method will be presented in
the talk.
The method has recently been applied to study the nuclei 43 Sc and 44,45,46 Ti using the reactions 46 Ti(p,x γ)X. In
45 Ti, steps in the level density as a function of excitation energy have been observed. The nucleus 44 Ti is expected to be exclusively produced in supernovae. The abundance observed is therefore regarded as a marker for the type of supernova. The nuclear level density of 44 Ti is an important input for modelling the production of 44 Ti in the
stellar environment. Preliminary results on level densities and γ-ray strength functions for 43 Sc and 44,45,46 Ti will be presented.
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Bürger, Alexander; Syed, Naeem Ul Hasan; Larsen, Ann-Cecilie; Guttormsen, Magne Sveen; Harissopulos, Sotirios & Kmiecik, M.
[Vis alle 16 forfattere av denne artikkelen]
(2009).
Level Densities and Strength Functions in Light Sc and Ti Isotopes.
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Toft, Heidi Kristine; Bürger, Alexander; Guttormsen, Magne Sveen; Larsen, Ann-Cecilie; Nyhus, Hilde-Therese & Siem, Sunniva
[Vis alle 8 forfattere av denne artikkelen]
(2009).
Level Densities and Gamma Strength Functions in 116,118,119Sn.
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Bürger, Alexander; Larsen, Ann-Cecilie; Syed, Naeem Ul Hasan; Guttormsen, Magne Sveen; Harissopulos, Sotirios & Kmiecik, Marysia
[Vis alle 16 forfattere av denne artikkelen]
(2009).
Level density and gamma-ray strength function in 43Sc.
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Toft, Heidi Kristine; Bürger, Alexander; Guttormsen, Magne Sveen; Larsen, Ann-Cecilie; Nyhus, Hilde-Therese & Siem, Sunniva
[Vis alle 8 forfattere av denne artikkelen]
(2009).
Level Densities and Gamma Strength Functions in 116,118,118Sn.
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Guttormsen, Magne Sveen
(2008).
Finn Ingebretsen 70 år.
Fra Fysikkens Verden.
ISSN 0015-9247.
-
Nyhus, Hilde-Therese; Siem, Sunniva; Guttormsen, Magne Sveen; Larsen, Ann-Cecilie; Bürger, Alexander & Syed, Naeem Ul Hasan
[Vis alle 9 forfattere av denne artikkelen]
(2008).
Level Densities, Thermodynamics and Gamma-ray Strength Functions in 163,164Dy.
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Guttormsen, Magne Sveen
(2008).
Nuclear level density and its thermodynamical interpretation.
-
Guttormsen, Magne Sveen
(2008).
Physics at SAFE: Level density and thermodynamics of warm nuclei.
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Guttormsen, Magne Sveen
(2008).
Protonterapi.
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Voinov, Alexander; Grimes, S.M.; Brune, C.R.; Guttormsen, Magne Sveen; Massey, T.N. & Schiller, Andreas
[Vis alle 7 forfattere av denne artikkelen]
(2007).
Experimental Study of Level Density and gamma-strength Functions from Compound Nuclear Reactions.
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Guttormsen, Magne Sveen
(2007).
Syklotronlaboratoriet og protonterapi.
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Siem, Sunniva; Guttormsen, Magne Sveen; Chankova, Rositsa; Larsen, Ann-Cecilie; Rekstad, John Bernhard & Syed, Naeem Ul Hasan
[Vis alle 9 forfattere av denne artikkelen]
(2007).
Level densities and gamma-strength functions in rare earth nuclei.
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Guttormsen, Magne
(2007).
Nuclear Physics at the Oslo Cyclotron Laboratory.
Vis sammendrag
The low energy nuclear physics group has developed a method for measuring level density and photon strength functions in the continuum. These quantities are known from conventional nuclear spectroscopy near the ground state, but are little known at higher excitation energies. The instrumentation and methods will be briefly described. New and controversial experimental results using the Oslo method will also be presented.
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Larsen, Ann-Cecilie; Chankova, Rositsa; Guttormsen, Magne Sveen; Ingebretsen, Finn; Lönnroth, Tom & Messelt, Svein
[Vis alle 11 forfattere av denne artikkelen]
(2007).
Puzzling gamma-ray strength functions in 44,45Sc and 50,51V.
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Siem, Sunniva; Guttormsen, Magne; Larsen, Ann-Cecilie; Rekstad, John Bernhard; Syed, Naeem Ul Hasan & Schiller, Andreas
[Vis alle 7 forfattere av denne artikkelen]
(2006).
Level densities and gamma-ray strength functions in Sm isotopes.
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Siem, Sunniva; Guttormsen, Magne; Larsen, Ann-Cecilie; Rekstad, John Bernhard; Schiller, Andreas & Ødegård, Stein Westad
[Vis alle 8 forfattere av denne artikkelen]
(2006).
Level densities and gamma-ray strength functions in Sm isotopes.
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-
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Larsen, Ann-Cecilie; Guttormsen, Magne; Chankova, Rositsa; Ingebretsen, Finn; Lönnroth, Tom & Messelt, Svein
[Vis alle 11 forfattere av denne artikkelen]
(2006).
Radiative strength functions of warm nuclei in the 1f7/2 shell.
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Rekstad, John Bernhard; Siem, Sunniva; Guttormsen, Magne & Ingebretsen, Finn
(2005).
Syklotronlaboratoriet i Oslo, et senter for forskning og knoppskyting i 25 år.
Fra Fysikkens Verden.
ISSN 0015-9247.
s. 35–39.
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Guttormsen, Magne; Agvaanluvsan, Undraa; Chankova, Rositsa; Hjorth-Jensen, Morten; Rekstad, John Bernhard & Schiller, Andreas
[Vis alle 10 forfattere av denne artikkelen]
(2005).
Single particle entropy in heated nuclei.
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Algin, Emel; Schiller, Andreas; Voinov, Alexander; Agvaanluvsan, Undraa; Belgya, Thomas & Bernstein, Lee
[Vis alle 15 forfattere av denne artikkelen]
(2005).
Level densities and radiative strength functions in 56,57Fe and 96,97Mo.
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Voinov, Alexander; Grimes, S.M.; Agvaanluvsan, Undraa; Algin, Emel; Belgya, Thomas & Brune, C.R.
[Vis alle 13 forfattere av denne artikkelen]
(2005).
Level densities of iron isotopes and lower-energy enhancement of gamma-strength function.
-
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Lønnroth, Tom & Guttormsen, Magne
(2004).
Hur attrahera studerande till fysikstudier och ge dem en interessant undervisning?
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Sunde, Ann-Cecilie; Chankova, Rosita; Guttormsen, Magne; Ingebretsen, Finn; Lönnroth, Tom & Messelt, Svein
[Vis alle 10 forfattere av denne artikkelen]
(2004).
Thermal and electromagnetic properties in the light vanadium isotopes 50,51V.
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Siem, Sunniva; Guttormsen, Magne; Rekstad, John Bernhard; Chankova, Rosita & Sunde, Ann-Cecilie
(2004).
Study of the level density and gamma strength function using MINIBALL.
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Chankova, Rosita; Guttormsen, Magne; Sunde, Ann-Cecilie; Ingebretsen, Finn; Lønnroth, Tom & Messelt, Svein
[Vis alle 10 forfattere av denne artikkelen]
(2004).
Level density and gamma-decay properties of heated 93-98Mo isotopes.
-
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Siem, Sunniva; Guttormsen, Magne; Rekstad, John Bernhard; Chankova, Rositsa; Schiller, Andreas & Sunde, Ann-Cecilie
(2003).
Level densities and gamma strength functions.
-
Siem, Sunniva; Guttormsen, Magne & Rekstad, John Bernhard
(2003).
Thermodynamic and electromagnetic properties of nuclei.
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Voinov, Alexander; Schiller, Andreas; Guttormsen, Magne; Rekstad, John Bernhard & Siem, Sunniva
(2003).
Electromagnetic character of soft dipole modes in rare earth nuclei.
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Algin, Emel; Becker, J.A.; Bernstein, Lee; Garrett, P.E.; Guttormsen, Magne & Mitchell, Gary
[Vis alle 11 forfattere av denne artikkelen]
(2003).
Average Nuclear Level Densities and Radiative Strength Functions in 56,57Fe from Primary Gamma-Ray Spectra.
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Agvaanluvsan, Undraa; Schiller, Andreas; Becker, J.A.; Bernstein, Lee; Guttormsen, Magne & Mitchell, Gary
[Vis alle 9 forfattere av denne artikkelen]
(2003).
Level densities and radiative strength functions in 170,171Yb.
-
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Lønnroth, Tom; Guttormsen, Magne; Chankova, Rositsa; Melby, Elin; Rekstad, John Bernhard & Schiller, Andreas
[Vis alle 8 forfattere av denne artikkelen]
(2003).
Level Densities and Gamma-Ray Strength in Light Nuclei.
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Lønnroth, Tom; Guttormsen, Magne; Chankova, Rositsa; Sunde, Ann-Cecilie; Schiller, Andreas & Voinov, Alexander
(2003).
Light Nuclei at High Excitation: Study of Level Densities at Alpha-Cluster Energies.
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Guttormsen, Magne; Hjorth-Jensen, Morten; Rekstad, John Bernhard; Siem, Sunniva; Schiller, Andreas & Voinov, Alexander
(2003).
MEASUREMENTS OF NUCLEAR LEVEL DENSITIES AND GAMMA-RAY STRENGTH FUNCTIONS AND THEIR INTERPRETATIONS.
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Bagheri, Assadollah; Chankova, Rositsa; Guttormsen, Magne; Hjorth-Jensen, Morten; Ingebretsen, Finn & Messelt, Svein
[Vis alle 11 forfattere av denne artikkelen]
(2003).
Electromagnetic and thermodynamic proprties of rare earth nuclei.
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Schiller, Andreas; Guttormsen, Magne; Hjorth-Jensen, Morten; Rekstad, John Bernhard & Siem, Sunniva
(2002).
Caloric curves of nuclei.
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Schiller, Andreas; Bernstein, Lee; Voinov, Alexander; Guttormsen, Magne; Hjorth-Jensen, Morten & Rekstad, John Bernhard
[Vis alle 9 forfattere av denne artikkelen]
(2002).
Radiative strength functions and level densities.
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Siem, Sunniva; Guttormsen, Magne; Rekstad, John Bernhard; Schiller, Andreas & Voinov, Alexander
(2002).
Level densities and gamma strength functions: important quanteties in nucleosynthesis.
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Guttormsen, Magne; Rekstad, John Bernhard; Siem, Sunniva; Schiller, Andreas & Voinov, Alexander
(2002).
Extraction of level densities from primary gamma-spectra.
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Guttormsen, Magne; Hjorth-Jensen, Morten; Rekstad, John Bernhard; Siem, Sunniva; Schiller, Andreas & Voinov, Alexander
(2002).
Measurements of Nuclear Level Densities and Gamma-Ray Strength Functions and their Interpretations.
Vis sammendrag
A method to extract primary $\gamma$-ray spectra from particle-$\gamma$
coincidences at excitation energies up to the neutron binding energy is
described. From these spectra, the level density and $\gamma$-ray
strength function can be determined. From the level density, several
thermodynamical quantities are obtained within the microcanonical and
canonical ensemble. Also models for the $\gamma$-ray strength function
are discussed.
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Tavukcu, Emel; Mitchell, Gary; Guttormsen, Magne; Melby, Elin; Rekstad, John Bernhard & Siem, Sunniva
[Vis alle 9 forfattere av denne artikkelen]
(2001).
Bulk properties of ^56Fe.
Vis sammendrag
A technique to extract primary (first generation) \gamma rays has been developed by the Oslo Cyclotron group. The primary \gamma-ray spectrum represents the \gamma decay probability distribution, and it depends on the product of the level density at the final excitation energy and the radiative strength function, according to the Brink-Axel hypothesis. Within an iterative procedure, the level density and the radiative strength function can be extracted from the primary \gamma-ray spectra. The method has been applied to study ^56Fe which is close to a doubly magic core. The experiment was carried out with a 45-MeV ^3He beam using the (^3He,\alpha) reaction on a ^57Fe target at the Oslo Cyclotron Laboratory. New results of this experiment will be discussed.
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Schiller, Andreas; Guttormsen, Magne; Hjorth-Jensen, Morten; Melby, Elin; Rekstad, John Bernhard & Siem, Sunniva
[Vis alle 7 forfattere av denne artikkelen]
(2001).
Level density, thermodynamics and radiative strength.
Vis sammendrag
A method to measure level density (LD) and radiative strength (RS) below the particle threshold with previously unachieved accuracy has been developed. Using the (^3He,\alpha\gamma) reaction on rare earth nuclei at the Oslo Cyclotron Laboratory, the resulting LD and RS have been successful in describing (\gamma,\gamma') reaction cross-sections and total \gamma spectra following n capture, thereby verifying the unexpected resonant structure at 3~MeV in the RS, also observed by Igashira et al\rm. Since the LD essentially equals the \mu-canonical partition function (PF), temperature and heat capacity can be determined. Structures in these quantities have been related to Cooper-pair breaking. Laplace transformation of the LD yields the canonical PF. The shape of the canonical C_V(T) curve indicates quenching of pairing correlations at finite T, as predicted by Sano/ Yamasaki, Goodman and Tanabe/Sugawara-Tanabe long ago. New results and the possibility of a pairing phase transition are discussed.
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Guttormsen, Magne; Hjorth-Jensen, Morten; Ingebretsen, Finn; Melby, Elin; Messelt, Svein & Rekstad, John Bernhard
[Vis alle 8 forfattere av denne artikkelen]
(2001).
Thermodynamical properties in rare earth nuclei.
Vis sammendrag
The Oslo Cyclotron Group has established a method to extract primary gamma-ray spectra at excitation energies up to the neutron binding energy. From these energy distributions, the level density and gamma-ray strength function can be extracted. In this group report we focus on experimental thermodynamical quantities obtained within the microcanonical and canonical ensemble theory.
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Schiller, Andreas; Guttormsen, Magne; Hjorth-Jensen, Morten; Melby, Elin; Rekstad, John Bernhard & Siem, Sunniva
(2001).
Thermodynamical properties of rare earth nuclei: the melting of pair correlations.
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Schiller, Andreas; Guttormsen, Magne; Melby, Elin; Rekstad, John Bernhard; Siem, Sunniva & Voinov, Alexander
(2001).
Radiative strength function in deformed rare earth nuclei below the neutron binding energy.
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Siem, Sunniva; Guttormsen, Magne; Ingeberg, Kristian; Melby, Elin; Rekstad, John Bernhard & Schiller, Andreas
(2000).
Thermal quenching of pair correlations and gamma-strength functions in 148,149Sm.
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Schiller, Andreas; Guttormsen, Magne; Hjorth-Jensen, Morten; Melby, Elin; Rekstad, John Bernhard & Siem, Sunniva
(2000).
Level density and thermal properties in rare earth nuclei.
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Siem, Sunniva; Schiller, Andreas; Guttormsen, Magne; Hjorth-Jensen, Morten; Melby, Elin & Rekstad, John Bernhard
(2000).
Level density and thermal properties in rare earth nuclei.
-
Siem, Sunniva; Guttormsen, Magne; Hjorth-Jensen, Morten; Melby, Elin; Rekstad, John Bernhard & Schiller, Andreas
(2000).
Level densities and the thermal quenching of pair correlations in rare earth nuclei.
-
Guttormsen, Magne; Hjorth-Jensen, Morten; Melby, Elin; Rekstad, John Bernhard; Schiller, Andreas & Siem, Sunniva
(2000).
Thermal quenching of pair correlations in rare earth nuclei.
Vis sammendrag
The gamma-ray spectra of the (3He,alpha gamma) pick-up reaction on
162,163Dy and 172,173Yb are utilized to extract level densities. The
temperature T as function of excitation energy E is deduced within the
microcanonical ensemble. Oscillations in T(E) are interpreted as the
breaking of Cooper pairs. The deduced heat capacity in the canonical
ensemble shows an S-form indicating a critical temperature for
quenching of pair correlations at Tc = 0.50(4) MeV.
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Guttormsen, Magne; Hjorth-Jensen, Morten; Melby, Elin; Rekstad, John Bernhard; Schiller, Andreas & Siem, Sunniva
(2000).
Single quasiparticle entropy in excited nuclei with T < 1MeV.
Vis sammendrag
Entropies in rare earth nuclei are extracted from measured level
densities. The entropy difference between odd and even-even mass nuclei
are almost independent of excitation energy in the 1.5 - 6 MeV region.
A global study of level densities from so-called anchor points, reveals
that this is a common property for mid-shell nuclei. The findings
indicate thermodynamical extensivity, suggesting that each thermal
quasiparticle is carrying an entropy of appr. S = 2.
-
Guttormsen, Magne
(2000).
Thermodynamical properties of excited nuclei with T < 1MeV.
-
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Melby, Elin; Bergholt, Lisbeth; Guttormsen, Magne; Hjorth-Jensen, Morten; Ingebretsen, Finn & Messelt, Svein
[Vis alle 9 forfattere av denne artikkelen]
(1999).
Experimental temperature and heat capacity in rare earth nuclei.
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Schiller, Andreas; Bergholt, Lisbeth; Guttormsen, Magne; Melby, Elin; Messelt, Svein & Rekstad, John Bernhard
[Vis alle 7 forfattere av denne artikkelen]
(1999).
Level density and gamma-strength functions in rare earth nuclei.
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Rekstad, John Bernhard; Bergholt, Lisbeth; Guttormsen, Magne; Hjorth-Jensen, Morten; Ingebretsen, Finn & Melby, Elin
[Vis alle 9 forfattere av denne artikkelen]
(1999).
Measurements of level densities and gamma ray strength functions.
-
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Greenless, P.T.; Guttormsen, Magne; Messelt, Svein; Schiller, Andreas; Siem, Sunniva & Tveter, Trine Spedstad
(1999).
Identification of excited states in <SUP>226</SUP>U.
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Lonnroth, Tom; Kallman, K.; Guttormsen, Magne; Bergholt, Lisbeth; Bjerve, Amund & Ingeberg, Kristian
[Vis alle 8 forfattere av denne artikkelen]
(1999).
Spectroscopy with entry-state selection: Search for cluster-state gamma-ray emission.
-
Guttormsen, Magne
(1999).
Observation of thermodynamical properties in rare earth nuclei.
-
Lonnroth, Tom; Guttormsen, Magne & Schiller, Andreas
(1999).
New observation methods for alpha-particle elastic scattering. Microscopic properties of alpha cluster states.
-
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Melby, Elin; Bergholt, Lisbeth; Guttormsen, Magne; Huseby, I.; Rekstad, John Bernhard & Schiller, Andreas
[Vis alle 8 forfattere av denne artikkelen]
(1997).
K-selection in gamma-decay after ARC and thermal neutron capture.
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