Papers by Michael Wiescher
De Mortuis Nil Nisi Bene
Springer biographies, 2021
In the development of the new nuclear model, Haas worked closely with scientists from the Univers... more In the development of the new nuclear model, Haas worked closely with scientists from the University of Chicago. After a meeting in Chicago, where he had presented a talk on his latest results, he collapsed on the stairs of the conference hotel. He never recovered.
The Leipzig Professorship
Springer biographies, 2021
Haas maintained his interests in the history of science and with the help of the famous and influ... more Haas maintained his interests in the history of science and with the help of the famous and influential science historian Karl Sudhoff, he was appointed in 1914 as docent for science history and as lector of the Poggendorff Journal at the University of Leipzig. He gave several successful lectures on the topic but also gradually developed a strong interest in theoretical physics.
The Next Generation
Springer biographies, 2021
German Publishers
Springer biographies, 2021
Vienna Misery
Springer biographies, 2021
The Dark Years
Springer biographies, 2021
The dark years are the last years of Austrian independence in the shadow of Nazi Germany. Haas hi... more The dark years are the last years of Austrian independence in the shadow of Nazi Germany. Haas himself was under steady attack by Nazi sympathizers, in both Austria and Germany, who wanted him as a Jew to be removed from his post at the Vienna Academy. Haas responded by writing books for the public, describing the benefits of the scientific approach versus the pseudo-scientific claims made by Nazi representatives and followers. These years were further darkened by the murder of Dollfuẞ. Afraid of traveling to Germany, Haas sent his wife to negotiate with German publishers about his publishing income. In a number of rather entertaining reports, she describes the political changes that were taking place in Germany and the German publishing world. At last, Haas has the long-awaited position in America, albeit a temporary post.
University of Notre Dame
Springer biographies, 2021
Nuclear Physics Constraints on Neutrino Astrophysics
Handbook of Nuclear Physics
Vienna Exodus
Arthur E. Haas - The Hidden Pioneer of Quantum Mechanics, 2021
The History and Impact of the CNO Cycles in Nuclear Astrophysics
Physics in Perspective, 2018
The carbon cycle, or Bethe-Weizsäcker cycle, plays an important role in astrophysics as one of th... more The carbon cycle, or Bethe-Weizsäcker cycle, plays an important role in astrophysics as one of the most important energy sources for quiescent and explosive hydrogen burning in stars. This paper presents the intellectual and historical background of the idea of the correlation between stellar energy production and the synthesis of the chemical elements in stars on the example of this cycle. In particular, it addresses the contributions of Carl Friedrich von Weizsäcker and Hans Bethe, who provided the first predictions of the carbon cycle. Further, the experimental verification of the predicted process as it developed over the following decades is discussed, as well as the extension of the initial carbon cycle to the carbon-nitrogen-oxygen (CNO) multi-cycles and the hot CNO cycles. This development emerged from the detailed experimental studies of the associated nuclear reactions over more than seven decades. Finally, the impact of the experimental and theoretical results on our present understanding of hydrogen burning in different stellar environments is presented, as well as the impact on our understanding of the chemical evolution of our universe.
Experimental problems in nuclear astrophysics
ABSTRACT
DIANA - A deep underground accelerator for nuclear astrophysics experiments
AIP Conference Proceedings, 2013
ABSTRACT DIANA (Dakota Ion Accelerator for Nuclear Astrophysics) is a proposed facility designed ... more ABSTRACT DIANA (Dakota Ion Accelerator for Nuclear Astrophysics) is a proposed facility designed to be operated deep underground. The DIANA collaboration includes nuclear astrophysics groups from Lawrence Berkeley National Laboratory, Michigan State University, Western Michigan University, Colorado School of Mines, and the University of North Carolina, and is led by the University of Notre Dame. The scientific goals of the facility are measurements of low energy nuclear cross-sections associated with sun and pre-supernova stars in a laboratory setup at energies that are close to those in stars. Because of the low stellar temperatures associated with these environments, and the high Coulomb barrier, the reaction cross-sections are extremely low. Therefore these measurements are hampered by small signal to background ratios. By going underground the background due to cosmic rays can be reduced by several orders of magnitude. We report on the design status of the DIANA facility with focus on the 3 MV electrostatic accelerator.
Reactions with radioactive beams and explosive nucleosynthesis
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 1998
Page 1. Reactions with radioactive beams and explosive nucleosynthesis By M. Wiescher1, H. Schatz... more Page 1. Reactions with radioactive beams and explosive nucleosynthesis By M. Wiescher1, H. Schatz1 and AE Champagne2 1Department of Physics, University of Notre Dame, Notre Dame, IN 46556, USA 2Department of Physics ...
Nuclear Reactions
Astrophysics and space science library, 2018
Nuclear Physics A, 2010
Studies have shown that alpha-induced nuclear reactions in the hot CNO cycles and on the waiting ... more Studies have shown that alpha-induced nuclear reactions in the hot CNO cycles and on the waiting points of the rp-process play a principal role in energy production and nucleosynthesis on the surface of mass-accreting white dwarfs and neutron stars. This paper will present recent measurements at Notre Dame on the rate of 15 O(α,γ) and new experiments for (α,p) reactions on the waiting point nuclei of 14 O and 26 Si. Preliminary results and astrophysical implications will be discussed.
Nuclear physics far from stability and explosive nucleosynthesis processes
Il Nuovo Cimento A, 1998
... Therefore, only the extended CN(O)-, the NeNa-, MgAl-, SiP-, SCl-, ArK-and CaSc-cycles exist ... more ... Therefore, only the extended CN(O)-, the NeNa-, MgAl-, SiP-, SCl-, ArK-and CaSc-cycles exist ... It should be mentioned, at this point, that this interpretation is in contradiction with the conclusions of other authors [52, 53] who prefer a mathemati-cal Fourier-type analysis, assuming ...
Radiative capture reactions and α-elastic scattering on 106Cd for the astrophysical p-process
AIP Conference Proceedings, 2006
In the present work both the (alpha,gamma) and (p,gamma) cross sections on the p-nucleus 106Cd ha... more In the present work both the (alpha,gamma) and (p,gamma) cross sections on the p-nucleus 106Cd have been measured in the energy range relevant to the astrophysical p-process. The results are compared with the predictions of the statistical model calculations implemented with the NON-SMOKER code using different input parameters. The proton capture cross section has also been measured for 108Cd. The
Reaction rates and reaction sequences in the rp-process
The Astrophysical Journal, 1994
ABSTRACT
O-17(n, alpha)C-14 - Closure of a primordial CNO bi-cycle?
The Astrophysical Journal, 1993
ABSTRACT
A measurement of the C-14(n, gamma)C-15 cross section at a stellar temperature of kT = 23.3 keV
The Astrophysical Journal, 1992
A fast cyclic activation technique is used to determine the capture cross section of C-14. The me... more A fast cyclic activation technique is used to determine the capture cross section of C-14. The measurements were carried out at the Karlsruhe 3.75-MV pulsed Van de Graaff accelerators using the 7Li(p, n) reaction close to the reaction threshold to generate neutrons with a distribution resembling a Maxwell spectrum of 25 keV. The activation sample consisted of 605 +/- 15 mg carbon powder enriched in C-14 by 89 percent. The C-14 capture cross section was measured relative to the Au-197 standard cross section. The activity produced by the neutron captures in the C-14 sample was counted with a high-resolution HPGe detector via the characteristic 5297.79 keV C-15 gamma-ray line. The C-14 capture cross section at 23.3 keV was found to be (1.72 +/- 0.43) microbarn.
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Papers by Michael Wiescher