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E. Fischbach

Publications and source records attributed to E. Fischbach.

At least 19 recordsLinked to original sources
arXiv2025

Possibility of Inducing $^{241}$Am Fluctuations (Primakoff Photon-Magnetic Field Coupling Experiment)

This paper reports on results from an experiment designed to search for exotic particles interacting with nuclear matter. These particles could be created through the Primakoff coupling between photons and an external magnetic field. Theory suggests this coupling leads to the production of weakly interacting particles (e.g. axions) that are important to understanding the lack of a measured neutron electric dipole moment (nEDM). The current experiment has been run to look for evidence of weakly interacting particles, created by photons propagating through a magnetic field, by studying their influence on the measured decay spectrum of Americium (241Am). The results shown here reflect a statistically significant difference (sigma > 6.0) between observed decays when the experiment was run in a mode that allowed photons to traverse a magnetic field (light mode or sP for system-Photons) when compared to a second mode where the light was blocked from entering the cavity (dark mode or sD for system-Dark). This difference was observed to impact the count rate for the release of a 59.54keV gamma from 237Np. Repeated experimentation suggests the effect is robust and not due to spurious changes in background events. This could be confirmation that the Primakoff mechanism has been observed for visible photons. As importantly, this experiment looks at the possibility to develop a novel nuclear instrument that can modify nuclear decay rates.

nucl-ex↗
arXiv2025

Measuring $^{241}$Am Dipole Response

Americium ($^{241}$Am) with an unpaired proton in the F$_{5/2}$ state exhibits a significant magnetic dipole moment. The dipole can be experimentally measured with application of even modest external magnetic fields, as little as 1G, as a shifting in the energy spectrum of emitted gammas during the process of decaying to $^{237}$Np ground state. This paper looks at the shifting in the output energy peak of gammas from the decay of excited $^{237}$Np when two configurations of an external magnetic field are applied. The peak shifting, which does not appear in the background data dominated by $^{238}$U decays, differs for the two dominant gammas released at 26.3 keV and 59.5 keV. For the 59.5 keV peak: shifting is ~ 32% of 1-Energy Bin or about 0.5 keV. While for the 26.3 keV peak: shifting is ~ 15% of 1-Energy Bin or about 0.24 keV. Interestingly enough, there appears to be a shifting for the case where the field remains in a direction horizontal to the optical bench and the light is simply blocked or unblocked from entering the field, referred to as the light (sP) or dark (sD) modes.

nucl-ex↗
arXiv2022

Radon Decays and Their Implications for Elementary Particle Physics

This paper presents a new analysis of the observations of radon decay in an enclosed environment by the Geological Survey of Israel (GSI) between 2007 and 2012 [4]; for a more complete list of experiments performed by GSI on radon see also references [1-3]. The data exhibit a large peak around local noon followed by an abrupt drop, and by a second peak around 6PM local time. Additionally, there is also a very low amplitude peak occurring before daybreak. The salient features of the GSI radon decay data can be modeled as arising from a change in the radon decay rate, rather than due to the changes in the local concentration of radon (N0). Such a model may provide a clue to long theorized axionic, dark matter, interactions. Finally, new experimentation is suggested that can distinguish between changes in N0 versus changes in decay rate. Should a follow-up experiment show an effect similar to that seen in GSI, this could have significant implications for elementary particle physics.

nucl-ex↗
arXiv2021

Relationships among detector signals recorded during events SN1987A and GW170817

The temporal coincidences of events detected in four neutrino detectors and two gravitational antennas still remains among the most puzzling phenomena associated with SN1987A. The coincidences form a six-hour signal approximately coincident in time with the well-known LSD signal at 2h52m UT on 23/02/1987. After 30 years of research, the characteristics and the shape of the six-hour signal have been studied quite well, but the mechanisms of its formation have not been fully understood as of yet. Here we suggest that data obtained from another technology, radioactive decays, might provide new insights into the origin of signals previously seen in neutrino detectors and gravity wave detectors. On August 17, 2017, at 12h41m UT, the GW170817 signal was detected by LIGO and Virgo. At the same time, an approximately 7-hour long signal coincident with GW170817 was detected in the Si/Cl experiment on precision measurement of the $^{32}$Si half-life. We show that the Si/Cl signal is unexpectedly similar to the six-hour signal from SN1987A. In addition, we establish that the sources of the coinciding events are similar to those of the Si/Cl signal. To explain the surprising similarities in both signals, we present a mechanism which could in principle account for this phenomenon in terms of a local increase in the density of axionic dark matter induced by a gravity wave.

nucl-ex↗
arXiv2021

Constraints on the Dimensionality of Space

Complex structures can only form in a universe that allows for bound states. While this is clearly observed in three-dimensions, added degrees of freedom in a higher-dimensional space preclude the immediate assumption that binding potentials can in fact exist. In this paper, we derive a constraint on the dimensionality of a universe in the presence of an arbitrary set of forces. We then apply this constraint to systems with several example potentials. In doing so, we find that bound states in higher than 3 dimensions are in fact possible under specific circumstances which we characterize.

physics.class-ph↗
arXiv2020

Anomalies in Radioactive Decay Rates: A Bibliography of Measurements and Theory

Knowledge of the decay rates (or half-lives) of radioisotopes is critical in many fields, including medicine, archeology, and nuclear physics, to name just a few. Central to the many uses of radioisotopes is the belief that decay rates are fundamental constants of nature, just as the masses of the radioisotopes themselves are. Recently, the belief that decay rates are fundamental constants has been called into question following the observation of various reported anomalies in decay rates, such as apparent periodic variations. The purpose of this bibliography is to collect in one place the relevant literature on both sides of this issue in the expectation that doing so will deepen our understanding of the available data.

nucl-ex↗
arXiv2020

Generalized Analysis of the Eötvös Experiment

We present a generalized phenomenological formalism for analyzing the original Eötvös experiment in the presence of gravity and a generic "5th force." To date no evidence for a 5th force has emerged since its presence was suggested by a 1986 reanalysis of the 1922 publication coauthored by Eötvös, Pekàr, and Fekete (EPF). However, our generalized analysis introduces new mechanisms capable in principle of accounting for the EPF data, while at the same time avoiding detection by most recent experiments carried out to date. As an example, some of these mechanisms raise the possibility that the EPF signal could have arisen from an unexpected direction if it originated from the motion of the Earth through a medium.

hep-ph↗
arXiv2019

An Oscillation Evident in Both Solar Neutrino Data and Radon Decay Data

Analyses of neutrino measurements acquired by the Super-Kamiokande Neutrino Observatory (SK, for the time interval 1996 - 2001) and of radon decay measurements acquired by the Geological Survey of Israel (GSI, for the time interval 2007 - 2017) yield remarkably consistent detections of the same oscillation: frequency 9.43 +/- 0.04 year-1 (SK), 9.44 +/- 0.04 year-1 (GSI); amplitude 6.8 +/- 1.7 % (SK), 7.0 +/- 1.0 % (GSI); phase 124 +/- 15 deg. (SK), 124 +/- 9 deg. (GSI). We briefly discuss possible hypotheses that may be relevant to this experimental result.

hep-ph↗
arXiv2018

Indications of an unexpected signal associated with the GW170817 binary neutron star inspiral

We report experimental evidence at the 2.5$σ$ level for an unexpected signal associated with the GW170817 binary neutron star inspiral. This evidence derives from a laboratory experiment simultaneously measuring the $β$-decay rates of Si-32 and Cl-36 in a common detector. Whereas the Si-32 and Cl-36 decay rates show no statistical correlation before or after the inspiral, they are highly correlated ($\sim 95\%$) in the 5 hour time interval immediately following the inspiral. If we interpret this correlation as arising from the influence of particles emitted during the inspiral, then we can estimate the mass $m_{x}$ of these particles from the time delay between the gravity-wave signal and a peak in the $β$-decay data. We find for particles of energy 10 MeV, $m_{x}$ $\lesssim$ 16 eV which includes the neutrino mass region $m_ν$ $\lesssim$ 2 eV. The latter is based on existing limits for the masses $m_{i}$ of the three known neutrino flavors. Additionally, we find that the correlation is even stronger if we include data in the 80 minute period before the arrival of the gravity wave signal. Given the large number of radionuclides whose decays are being monitored at any given time, we conjecture that other groups may also be in a position to search for statistically suggestive fluctuations of radionuclide decay rates associated with the GW170817 inspiral, and possibly with other future inspirals.

astro-ph.HE↗
arXiv2017

Analysis of Ten Years of Radon-Chain Decay Measurements: Evidence of Solar Influences and Inferences Concerning Solar Internal Structure and the Role of Neutrinos

Gamma radiation associated with radon decay exhibits variations in both time of year and time of day. The annual oscillation has its maximum value in June, suggestive of a galactic influence. Measurements made at midnight show strong evidence of an influence of solar rotation, but measurements made at noon do not. We find several pairs of oscillations with frequencies separated by 1 cycle per year that is suggestive of an influence of rotation that is oblique with respect to the normal to the ecliptic. We suggest that beta decays may be stimulated by neutrinos and that the decay products tend to travel in the same direction as the neutrinos. We estimate the relevant cross section.

astro-ph.SR↗
arXiv2016

Is there a signal for Lorentz non-invariance in existing radioactive decay data?

Measurements of the beta decay rates of nuclei have revealed annual periodicities with approximately the same relative amplitude even though the half-lives range over nine orders of magnitude. Here we show that this can be explained if the emitted neutrinos behave as if they propagate in a medium with a refractive index which varies as the Earth orbits the sun. This refractive index may be due to fundamental Lorentz non-invariance (LNI), or apparent LNI arising from interactions with solar or relic neutrinos, or dark matter. Additionally, this medium could have consequences for experiments attempting to measure the neutrino mass.

hep-ph↗
arXiv2016

Search for Perturbations of Nuclear Decay Rates Induced by Reactor Electron Antineutrinos

We report the results of an experiment conducted near the High Flux Isotope Reactor of Oak Ridge National Laboratory, designed to address the question of whether a flux of reactor-generated electron antineutrinos can alter the rates of weak nuclear interaction-induced decays for Mn-54, Na-22, and Co-60. This experiment, while quite sensitive, cannot exclude perturbations less than one or two parts in $10^4$ in $β$ decay (or electron capture) processes, in the presence of an antineutrino flux of $3\times 10^{12}$ cm$^{-2}$ s$^{-1}$. The present experimental methods are applicable to a wide range of isotopes. Improved sensitivity in future experiments may be possible if we can understand and reduce the dominant systematic uncertainties.

nucl-ex↗
arXiv2016

Stronger limits on hypothetical Yukawa interactions in the 40--8000 nm range

We report the results of new differential force measurements between a test mass and rotating source masses of gold and silicon to search for forces beyond Newtonian gravity at short separations. The technique employed subtracts the otherwise dominant Casimir force at the outset and, when combined with a lock-in amplification technique, leads to a significant improvement (up to a factor $10^{3}$) over existing limits on the strength (relative to gravity) of a putative force in the 40--8000 nm interaction range.

hep-ex↗
arXiv2015

Comparative Analysis of Brookhaven National Laboratory Nuclear Decay Data and Super-Kamiokande Neutrino Data: Indication of a Solar Connection

An experiment carried out at the Brookhaven National Laboratory from February 1982 to December 1989 acquired 364 measurements of the beta-decay rates of a sample of 36Cl and of a sample of 32Si. The experimenters reported finding small periodic annual deviations of the data points from an exponential decay - of uncertain origin. We here analyze this dataset by power spectrum analysis and by forming spectrograms and phasegrams. We confirm the occurrence of annual oscillations but we also find evidence of oscillations in a band of frequencies appropriate for the internal rotation of the Sun. Both datasets show clear evidence of a transient oscillation with a frequency of 12.7 cycles per year that falls in the range of rotational frequencies for the solar radiative zone. We repeat these analyses for 358 neutrino measurements acquired by Super-Kamiokande over the interval May 1986 to August 2001. Spectrogram analysis yields a strong and steady oscillation at about 9.5 cycles per year and an intermittent oscillation with frequency in the range 12.5 - 12.7 cycles per year. We attribute the former to rotation of the solar core and the latter to rotation in the radiative zone. Since the flux of neutrinos (8B neutrinos) responsible for the Super-Kamiokande measurements is known, we are able to estimate the cross sections for the beta-decay oscillations at 12.7 cycles per year. These estimates are found to be 10-21.6 cm-2 for 36Cl and 10-18.4 cm-2 for 32Si. We suggest that the beta-decay process is influenced by neutrinos, and that the solar neutrino flux is modulated by magnetic field in the deep solar interior by Resonant Spin Flavor Precession.

hep-ph↗