Negative / Null Result ReportOpen accessPhysics
Qiu-Ju Huang, Bao Wang, Jun-Jie Wei et al. · 2025 · arXiv
Axions or axion-like particles (ALPs) are well-motivated dark matter (DM) candidates whose coupling to photons induces periodic oscillations in the polarization angle of astrophysical light. This work reports the first search for such a signature using ten years of optical polarimetric monitoring of the blazar 1ES 1959+650. No statistically significant periodicity is detected using a Lomb-Scargle periodogram and Monte Carlo analysis. Assuming a central DM density in the host galaxy, this null result places tight upper limits on the ALP-photon coupling constant at $g_{aγ}<(5.8 \times 10^{-14}-1
Negative / Null Result ReportOpen accessPhysics
David T. F Weldrake, Penny D Sackett, Kenneth C Freeman et al. · 2004 · arXiv
We present the results of a comprehensive wide field search for transiting ``Hot Jupiter'' planets (1d<P<16d) in the globular cluster 47 Tucanae. Motivated by the core null result of Gilliland and coworkers, this work further addresses the question of giant planet frequency in 47 Tuc by observing, from the ground, a 52'x52' field centered on the cluster for 30.4 nights. Hence this work is most sensitive to the uncrowded outer regions of the cluster and concentrates on 21,920 main sequence stars (~solar in mass). This work comprises the largest ground-based transit search of a globular cluster
Negative / Null Result ReportOpen accessComputer Science
K. S. Babu, Sandip Pakvasa · 2002 · arXiv
We show that lepton number violating muon decays, μ^+ -> e^+ + ν_e-bar + ν_i-bar (i=e, μor τ), can consistently explain the neutrino anomaly reported by the LSND experiment. Two effective operators in the Standard Model are identified which lead to just such decays and no other processes. The scale of new physics Λmust be relatively low, Λ< 500 GeV. Extensions of the Standard Model which realize these effective operators are presented. Since new physics affects only the decay of the muon, and not of π^+-, our scenario predicts a null result for ν_μ-bar - ν_e-bar oscillation searches at the Fer
Negative / Null Result ReportOpen accessPhysics
Isobel Falconer · 2016 · arXiv
In 1877 James Clerk Maxwell and his student Donald MacAlister refined Henry Cavendish's 1773 null experiment demonstrating the absence of electricity inside a charged conductor. This null result was a mathematical prediction of the inverse square law of electrostatics, and both Cavendish and Maxwell took the experiment as verifying the law. However, Maxwell had already expressed absolute conviction in the law, based on results of Michael Faraday's. So, what was the value to him of repeating Cavendish's experiment? After assessing whether the law was as secure as he claimed, this paper explores
Negative / Null Result ReportOpen accessPhysics
Rodrigo de Abreu, Vasco Guerra · 2005 · arXiv
In a previous work we have shown that the null result of the Michelson-Morley experiment in vacuum is deeply connected with the notion of time. The same is true for the the postulate of constancy of the two-way speed of light in vacuum in all frames independently of the state of motion of the emitting body. The argumentation formerly given is very general and has to be true not only within Special Relativity and its `equivalence' of all inertial frames, but as well as in Lorentz-Poincaré scenario of a preferred reference frame. This paper is the second of a trilogy intending to revisit the fou
Negative / Null Result ReportOpen accessPhysics
Jeremy Darling, Paul Goldsmith, Di Li et al. · 2003 · arXiv
We report the results of a search for 6.7 GHz methanol (CH3OH) maser emission in OH megamaser galaxies at 0.11<z<0.27. No detections were made in the 25 objects observed down to rms noise levels of roughly 0.6 mJy in 150 kHz channels. The OH megamaser sample includes OH emission of all observed types: narrow and broad, physically compact and extended, variable and quiescent, and from simple single lines to multi-component complexes to lines with high velocity wings. Our null result indicates, for the widest possible range of OH megamaser environments, that methanol masing does not scale with O
Negative / Null Result ReportOpen accessComputer Science
C. Abel, N. J. Ayres, G. Ban et al. · 2017 · arXiv
We report on a search for ultra-low-mass axion-like dark matter by analysing the ratio of the spin-precession frequencies of stored ultracold neutrons and $^{199}$Hg atoms for an axion-induced oscillating electric dipole moment of the neutron and an axion-wind spin-precession effect. No signal consistent with dark matter is observed for the axion mass range $10^{-24}~\textrm{eV} \le m_a \le 10^{-17}~\textrm{eV}$. Our null result sets the first laboratory constraints on the coupling of axion dark matter to gluons, which improve on astrophysical limits by up to 3 orders of magnitude, and also im
Negative / Null Result ReportOpen accessPhysics
Diego F. Torres, Stephen Reucroft, Olaf Reimer et al. · 2003 · arXiv
With the aim of testing recent claims for a particularly strong correlation between ultra-high energy cosmic rays (UHECRs), observed with the AGASA and the Yakutsk experiments, and a sample of BL Lacertae (BL Lacs), we here conduct a blind statistical assessment. We search for associations between the same set of BL Lac objects and the arrival directions of 33 relevant UHECRs observed with the Haverah Park and the Volcano Ranch experiments. Within the accuracy of angle determination, there are no positional coincidences. The probability that this null result arises as a statistical fluctuation
Negative / Null Result ReportOpen accessComputer Science
C. Abel, N. J. Ayres, G. Ban et al. · 2022 · arXiv
Ultra-low-mass axions are a viable dark matter candidate and may form a coherently oscillating classical field. Nuclear spins in experiments on Earth might couple to this oscillating axion dark-matter field, when propagating on Earth's trajectory through our Galaxy. This spin coupling resembles an oscillating pseudo-magnetic field which modulates the spin precession of nuclear spins. Here we report on the null result of a demonstration experiment searching for a frequency modulation of the free spin-precession signal of \magHg in a \SI{1}{\micro\tesla} magnetic field. Our search covers the axi
Negative / Null Result ReportOpen accessComputer Science
Bin Zhu, Xuewen Liu · 2021 · arXiv
Flavor-specific scalar bosons exist in various Standard Model extensions and couple to a single generation of fermions via a global flavor symmetry breaking mechanism. Given this strategy, we propose a MeV flavor-specific scalar model in dimension-$5$ operator series, which explains the muon g-2 anomaly and proton radius puzzle by coupling with the muon and down-quark at the same time. The framework is consistent with the null result of high-intensity searches. Specifically, the supernova constraints for muon couplings become weakened by including the contribution of down-quark interaction. Th
Negative / Null Result ReportOpen accessPhysics
Kaustubh Rajwade, Duncan Lorimer, Loren Anderson · 2016 · arXiv
Although high-sensitivity surveys have revealed a number of highly dispersed pulsars in the inner Galaxy, none have so far been found in the Galactic centre (GC) region, which we define to be within a projected distance of 1~pc from Sgr~A*. This null result is surprising given that several independent lines of evidence predict a sizable population of neutron stars in the region. Here, we present a detailed analysis of both the canonical and millisecond pulsar populations in the GC and consider free-free absorption and multi-path scattering to be the two main sources of flux density mitigation.
Negative / Null Result ReportOpen accessPhysics
Shunke Ai, He Gao · 2022 · arXiv
GRB 221009A is a bright Gamma-ray burst (GRB) with isotropic energy being larger than $10^{54} ~{\rm ergs}$. Its fairly low redshift makes it a promising candidate for high energy neutrino detection. However, a neutrino search for this GRB reported by the IceCube collaboration yielded a null result. In this paper, we utilize the upper limit from IceCube observation to test different GRB prompt emission models. We find that, at least for this specific burst, the dissipative photosphere model could be ruled out in a large parameter space. The internal shock model can survive only with a large bu
Negative / Null Result ReportOpen accessComputer Science
Ole Host, Ofer Lahav, Filipe B. Abdalla et al. · 2007 · arXiv
We present a showcase for deriving bounds on the neutrino masses from laboratory experiments and cosmological observations. We compare the frequentist and Bayesian bounds on the effective electron neutrino mass m_beta which the KATRIN neutrino mass experiment is expected to obtain, using both an analytical likelihood function and Monte Carlo simulations of KATRIN. Assuming a uniform prior in m_beta, we find that a null result yields an upper bound of about 0.17 eV at 90% confidence in the Bayesian analysis, to be compared with the frequentist KATRIN reference value of 0.20 eV. This is a signif
Negative / Null Result ReportOpen accessComputer Science
D. V. Ahluwalia, S. P. Horvath · 2010 · arXiv
In the very special relativity (VSR) proposal by Cohen and Glashow, it was pointed out that invariance under HOM(2) is both necessary and sufficient to explain the null result of the Michelson-Morely experiment. It is the quantum field theoretic demand of locality, or the requirement of P, T, CP, or CT invariance, that makes invariance under the Lorentz group a necessity. Originally it was conjectured that VSR operates at the Planck scale; we propose that the natural arena for VSR is at energies similar to the standard model, but in the dark sector. To this end we provide an ab initio spinor r
Negative / Null Result ReportOpen accessComputer Science
Alejandro Ibarra, Andreas Rappelt · 2017 · arXiv
We present a method to calculate, without making assumptions about the local dark matter velocity distribution, the maximal and minimal number of signal events in a direct detection experiment given a set of constraints from other direct detection experiments and/or neutrino telescopes. The method also allows to determine the velocity distribution that optimizes the signal rates. We illustrate our method with three concrete applications: i) to derive a halo-independent upper limit on the cross section from a set of null results, ii) to confront in a halo-independent way a detection claim to a
Negative / Null Result ReportOpen accessPhysics
D. Sarenac, O. Lailey, D. V. Garrad et al. · 2026 · arXiv
A recent proposal suggested that neutron orbital angular momentum (OAM) states could be detected via spin-polarized absorption in polarized 3He, with predicted cross-section variations linked to the neutron's OAM. We experimentally tested this hypothesis using spin-polarized neutron beams with OAM =-2 to 2, generated by fork-dislocation phase-gratings, and transmitted through a polarized 3He cell. Within statistical precision, no OAM-dependent change in the absorption cross section was observed. This null result places stringent constraints on polarized 3He-based OAM detection schemes. The abs
Negative / Null Result ReportOpen accessPhysics
D. Apai, M. R. Meyer, P. Hinz et al. · 2007 · arXiv
We present results from two high-contrast imaging surveys that exploit a novel technique, L-band angular differential imaging. Our first survey targeted 21 young stars in the Beta Pic and Tuc-Hor moving groups with VLT/NACO reaching typical sensitivities of 20 AU. The statistical analysis of the null result demonstrates that the giant planet population is truncated at 30 AU or less (90% confidence level). Our second, on-going MMT/Clio survey utilizes the unique sensitivity achieved in the L-band for old planets to probe all M-dwarf stars within 6 pc. The proximity of these targe
Negative / Null Result ReportOpen accessPhysics
Chuan-Ren Chen, Yu-Kuang Chu, Ho-Chin Tsai · 2015 · Physics Letters B
Even though the sensitivity of direct dark matter search experiments reaches the level of about 10−45 cm2, no confident signal of dark matter has been observed. We point out that, if dark matter is a vector boson, the null result in direct dark matter search experiments may be due to the destructive effects in dark-matter–nucleon elastic scattering. We illustrate the scenario using a modified Higgs portal model that includes exotic quarks. The significant cancellation can occur for a certain mass gap between new heavy quark and dark matter. As a result, the spin-independent dark-matter–nucleon
View details →DOI: 10.1016/j.physletb.2014.12.043 Negative / Null Result ReportOpen accessElementary particle physics
John K. Webb, Chung-Chi Lee, Dinko Milaković · 2022 · Universe
Recent advances in spectroscopic instrumentation and calibration methods dramatically improve the quality of quasar spectra. Supercomputer calculations show that, at high spectral resolution, procedures used in some previous analyses of spacetime variations of fundamental constants are likely to generate spurious measurements, biased systematically towards a null result. Developments in analysis methods are also summarised and a prescription given for the analysis of new and forthcoming data.
View details →DOI: 10.3390/universe8050266 Negative / Null Result ReportOpen accessPhysics
Javier De Miguel, Evanthia Hatziminaoglou, Frédéric Poidevin et al. · 2026 · Physics Letters B
We report a mm-wave search for axion dark matter from SGR 1745–2900, based on 4.8 h of ALMA observations. No candidate features are found between 133.99–135.78, 135.91–137.70, 145.99–147.78, and 147.99–149.78 GHz, corresponding to 0.55–0.62 meV. Interpreting this null result within a state-of-the-art stellar framework, we derive sensitivity to the axion–photon coupling at the level of gγ≳2×10−11 GeV−1 under a standard Navarro–Frenk–White profile; down to gγ≳2×10−13 GeV−1 upon accounting for a dense dark-matter spike around Sagittarius A*, probing the quantum chromodynamics axion parameter spac
View details →DOI: 10.1016/j.physletb.2026.140567 Negative / Null Result ReportOpen accessPolitical science (General)
Jeremy Ferwerda, Sascha Riaz · Political Science Research and Methods
Recent research suggests that local exposure to refugees does not increase support for far-right parties. We challenge this null result by drawing on granular data from Berlin in the wake of the Syrian refugee crisis. While prior work in the German context has generally assumed that refugee exposure is exogenous at the local level, we demonstrate that refugee housing was disproportionately concentrated in neighborhoods with young, non-citizen residents. To address this selection bias, we harmonize in-person and mail-in precinct boundaries across elections and implement a difference-in-differen
View details →DOI: 10.1017/psrm.2025.10061 Negative / Null Result ReportOpen accessAstrophysics
B. King, T. Heinzl, T. G. Blackburn · 2023 · European Physical Journal C: Particles and Fields
Abstract By combining an adiabatic approach based on a ‘locally monochromatic’ approximation with a local Hilbert transform, it is demonstrated how vacuum birefringence in the strong field regime can be calculated using a rate approach suitable for Monte Carlo simulation codes. Results for the flipping of the photon’s polarisation (helicity) are benchmarked with evaluation of exact expressions in a circularly (linearly) polarised plane wave of finite extent. For the circularly polarised case, the Heisenberg–Euler approach predicts a null result; an approximation similar to the ‘locally constan
View details →DOI: 10.1140/epjc/s10052-023-12074-w Negative / Null Result ReportOpen accessMedicine
Katie Finning, David A Richards, Victoria A Goodwin et al. · 2019 · BMJ Open
Objectives Physical rehabilitation is a complex process, and trials of rehabilitation interventions are increasing in number but often report null results. This study aimed to establish treatment success rates in physical rehabilitation trials funded by the National Institute of Health Research Health Technology Assessment (NIHR HTA) programme and examine any relationship between treatment success and the quality of intervention development work undertaken.Design This is a mixed methods study.Setting This study was conducted in the UK.Methods The NIHR HTA portfolio was searched for all complet
View details →DOI: 10.1136/bmjopen-2018-026289 Negative / Null Result ReportOpen accessPhysics
H. C. Eggers, B. Buschbeck · 2013 · Advances in High Energy Physics
A detailed understanding of all effects and influences on higher-order correlations is essential. At low charged multiplicity, the effect of a non-Poissonian multiplicity distribution can significantly distort correlations. Evidently, the reference samples with respect to which correlations are measured should yield a null result in the absence of correlations. We show how the careful specification of desired properties necessarily leads to an average-of-multinomials reference sample. The resulting internal cumulants and their averaging over several multiplicities fulfill all requirements of c
View details →DOI: 10.1155/2013/230515 Negative / Null Result ReportOpen accessPhysics
C. Abel, N. J. Ayres, G. Ban, G. Bison, K. Bodek, V. Bondar, E. Chanel, C. B. Crawford, M. Daum, B. Dechenaux, S. Emmenegger, P. Flaux, W. C. Griffith, P. G. Harris, Y. Kermaidic, K. Kirch, S. Komposch, P. A. Koss, J. Krempel, B. Lauss, T. Lefort, Prajwal MohanMurthy, Oscar Naviliat Cuncic, D. Pais, F. M. Piegsa, Guillaume Pignol, M. Rawlik, D. Ries, Stephanie Roccia, D. Rozpedzik, Philipp Schmidt-Wellenburg, N. Severijns, Y. V. Stadnik, J. A. Thorne, A. Weis, E. Wursten, Jacek Zejma, Geza Zsigmond · 2023 · SciPost Physics
Ultra-low-mass axions are a viable dark matter candidate and may form a coherently oscillating classical field. Nuclear spins in experiments on Earth might couple to this oscillating axion dark-matter field, when propagating on Earth's trajectory through our Galaxy. This spin coupling resembles an oscillating pseudo-magnetic field which modulates the spin precession of nuclear spins. Here we report on the null result of a demonstration experiment searching for a frequency modulation of the free spin-precession signal of \magHg in a 1 $\mu$T magnetic field. Our search covers the axion mass rang
View details →DOI: 10.21468/scipostphys.15.2.058 Negative / Null Result ReportOpen accessMedicine
Alexis David James Makin, Afzal Rahman, Marco Bertamini · 2020 · PLoS ONE
Previous work has shown that symmetrical stimuli are judged as lasting longer than asymmetrical ones, even when actual duration is matched. This effect has been replicated with different methods and stimuli types. We aimed to a) replicate the effect of symmetry on subjective duration, and b) assess whether it was further modulated by the number of symmetrical axes. There was no evidence for either effect. This null result cannot be explained by reduced statistical power or enhanced floor or ceiling effects. There is no obvious stimulus-based explanation either. However, we are mindful of the r
View details →DOI: 10.1371/journal.pone.0238554 Negative / Null Result ReportOpen accessConsciousness. Cognition
Ronald Andringa, Walter R. Boot, Nelson A. Roque et al. · 2018 · Cognitive Research
Abstract Placing one’s hands near an object has been reported to enhance visual processing in a number of ways. We explored whether hand proximity confers an advantage when applied to complex visual search. In one experiment, participants indicated the presence or absence of a target item in a baggage x-ray image by pressing response boxes located at the edge of a tablet computer screen, requiring them to grip the display between their hands. Alternatively, they responded using a mouse held within their lap. Contrary to expectations, hand position did not influence search performance. In a sec
View details →DOI: 10.1186/s41235-018-0094-7 Negative / Null Result ReportOpen accessAstrophysics
Yuta Hamada, Masatoshi Yamada · 2017 · European Physical Journal C: Particles and Fields
Abstract The null result in the LHC may indicate that the standard model is not drastically modified up to very high scales, such as the GUT/string scale. Having this in the mind, we suggest a novel leptogenesis scenario realized in the false vacuum of the Higgs field. If the Higgs field develops a large vacuum expectation value in the early universe, a lepton number violating process is enhanced, which we use for baryogenesis. To demonstrate the scenario, several models are discussed. For example, we show that the observed baryon asymmetry is successfully generated in the standard model with
View details →DOI: 10.1140/epjc/s10052-017-5215-9 Negative / Null Result ReportOpen accessOptics. Light
Alex Midasala · 2024 · Results in Optics
A viable solution to detect the one-way speed of light anisotropy in linear motion is by using an Isosceles triangle-shaped design for the experimental setup, from which two light pulses from both ends of one of the triangle’s sides are sent to the same clock upon the detection of the incident and the reflected pulse, thereby evading the need for synchronization. The relativistic effects are taken into account in the timing measurements by incorporating the Lorentz transformation equations of length contraction and time dilation, which produces a non-null result for the time difference of the
View details →DOI: 10.1016/j.rio.2024.100710 Negative / Null Result ReportOpen accessScience
Milton Gering, Tayla Johnson, Colin Tredoux · 2023 · South African Journal of Science
The effect of stress on face identification is not yet clear, with recent experiments finding positive, negative and null results. Here we report the results of two experiments examining the effect of stress on eyewitness performance in line-up face recognition tasks. Both experiments use a stress manipulation and live mock crime paradigm to examine the relationship between stress at encoding and subsequent line-up performance. Experiment 1 replicated an experiment by Sauerland et al. (Behav Sci Law. 2016;34(4):580–594) which induced stress using the Maastricht Acute Stress Test. The replicati
View details →DOI: 10.17159/sajs.2023/12102 