J. T. Gruenwald
Purdue University
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Featured researches published by J. T. Gruenwald.
Astroparticle Physics | 2009
Jere H. Jenkins; Ephraim Fischbach; J. B. Buncher; J. T. Gruenwald; D. E. Krause; J. J. Mattes
Abstract Unexplained periodic fluctuations in the decay rates of 32 Si and 226 Ra have been reported by groups at Brookhaven National Laboratory ( 32 Si), and at the Physikalisch–Technische–Bundesanstalt in Germany ( 226 Ra). We show from an analysis of the raw data in these experiments that the observed fluctuations are strongly correlated in time, not only with each other, but also with the time of year. We discuss both the possibility that these correlations arise from seasonal influences on the detection system, as well as the suggestion of an annual modulation of the decay rates themselves which vary with Earth–Sun distance.
Astroparticle Physics | 2010
D. Javorsek; P. A. Sturrock; R.N. Lasenby; A.N. Lasenby; J. B. Buncher; Ephraim Fischbach; J. T. Gruenwald; A. W. Hoft; T. J. Horan; Jere H. Jenkins; J. L. Kerford; R. H. Lee; A. Longman; J. J. Mattes; B. Morreale; D. B. Morris; R. Mudry; J. R. Newport; D. O’Keefe; M. A. Petrelli; M. A. Silver; C. A. Stewart; B. Terry
Abstract We provide the results from a spectral analysis of nuclear decay data displaying annually varying periodic fluctuations. The analyzed data were obtained from three distinct data sets: 32 Si and 36 Cl decays reported by an experiment performed at the Brookhaven National Laboratory (BNL), 56 Mn decay reported by the Children’s Nutrition Research Center (CNRC), but also performed at BNL, and 226 Ra decay reported by an experiment performed at the Physikalisch–Technische Bundesanstalt (PTB) in Germany. All three data sets exhibit the same primary frequency mode consisting of an annual period. Additional spectral comparisons of the data to local ambient temperature, atmospheric pressure, relative humidity, Earth–Sun distance, and their reciprocals were performed. No common phases were found between the factors investigated and those exhibited by the nuclear decay data. This suggests that either a combination of factors was responsible, or that, if it was a single factor, its effects on the decay rate experiments are not a direct synchronous modulation. We conclude that the annual periodicity in these data sets is a real effect, but that further study involving additional carefully controlled experiments will be needed to establish its origin.
arXiv: High Energy Physics - Phenomenology | 2010
Ephraim Fischbach; Jere H. Jenkins; J. B. Buncher; J. T. Gruenwald; P. A. Sturrock; D. Javorsek
Abstract : Recent reports of periodic fluctuations in nuclear decay data of certain isotopes have led to the suggestion that nuclear decay rates are being influenced by the Sun, perhaps via neutrinos. Here we present evidence for the existence of an additional periodicity that appears to be related to the Rieger periodicity well known in solar physics.
VIII LATIN AMERICAN SYMPOSIUM ON NUCLEAR PHYSICS AND APPLICATIONS | 2010
D. Javorsek; J. L. Kerford; C. A. Stewart; J. B. Buncher; Ephraim Fischbach; J. T. Gruenwald; J. Heim; A. W. Hoft; T. J. Horan; Jere H. Jenkins; M. Kohler; R. H. Lee; A. Longman; J. J. Mattes; T. Mohsinally; B. Morreale; D. B. Morris; R. Mudry; J. R. Newport; D. O’Keefe; M. A. Petrelli; M. A. Silver; P. A. Sturrock; B. Terry; H. Willenberg
Recent developments in efforts to determine the cause of anomalous experimental nuclear decay fluctuations suggest a possible solar influence. Here we report on the preliminary results from several nuclear decay experiments performed at Thule Air Base in Greenland during the Solar Eclipse that took place on 1 August 2008. Because of the high northern latitude and time of year, the Sun never set and thereby provided relatively stabilized conditions for nearly all environmental factors. An exhaustive list of relevant factors were monitored during the eclipse to help rule out possible systematic effects due to external influences. In addition to the normal temperature, pressure, humidity, and cloud cover associated with the outside ambient observations, we included similar measurements within the laboratory along with monitoring of the power supply output, local neutron count rates, and the Earth’s local magnetic and electric fields.
VIII LATIN AMERICAN SYMPOSIUM ON NUCLEAR PHYSICS AND APPLICATIONS | 2010
D. Javorsek; P. A. Sturrock; R.N. Lasenby; A.N. Lasenby; J. B. Buncher; Ephraim Fischbach; J. T. Gruenwald; Jere H. Jenkins; R. H. Lee; J. J. Mattes; D. B. Morris; R. Mudry; J. R. Newport
Recent comparisons of independent and unrelated nuclear decay experiments have shown unexplained oscillations that appear to be common in frequency and phase. The most logical explanation for this fluctuation would be some common systematic or environmental factor. In this paper we provide detailed spectral analysis comparisons of several environmental factors with nuclear decay data from an experiment performed at the Brookhaven National Laboratory. We demonstrate that, although none of the environmental factors investigated can be causal, comparisons with ACRIM solar irradiance measurements provide good agreement with the nuclear decay data. This analysis provides the first direct evidence that the cause of the fluctuations has a possible solar origin.
Space Science Reviews | 2009
Ephraim Fischbach; J. B. Buncher; J. T. Gruenwald; Jere H. Jenkins; D. E. Krause; J. J. Mattes; J. R. Newport
Astroparticle Physics | 2010
P. A. Sturrock; J. B. Buncher; Ephraim Fischbach; J. T. Gruenwald; D. Javorsek; Jere H. Jenkins; R. H. Lee; J. J. Mattes; J. R. Newport
Solar Physics | 2010
P. A. Sturrock; J. B. Buncher; Ephraim Fischbach; J. T. Gruenwald; D. Javorsek; Jere H. Jenkins; R. H. Lee; J. J. Mattes; J. R. Newport
Astroparticle Physics | 2016
T. Mohsinally; S. Fancher; M. Czerny; Ephraim Fischbach; J. T. Gruenwald; J. Heim; J.H. Jenkins; J. Nistor; D. O’Keefe
Physical Review D | 1976
Ephraim Fischbach; J. T. Gruenwald; Simon Peter Rosen; Harvey Spivack; A. Halprin; Boris Kayser