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Indirect Detection as a Window into Physics Beyond the Standard Model
Full text linkWhile the Standard Model has proven remarkably successful in describing nature at a fundamental level, several key questions remain unanswered, such as the origin of neutrino masses and the nature of dark matter. As a means of probing physics beyond the Standard Model, we present a comprehensive study of indirect detection strategies, focusing on several well-motivated extensions: sterile neutrinos, weakly interacting massive particles (WIMPs), higgsinos, and axions. For sterile neutrinos, WIMPs, and higgsinos, we conduct analyses under the assumption that these particles constitute the dark matter of the universe. We probe their annihilation or decay signatures using astrophysical observations from X-ray and gamma-ray telescopes, leveraging the dense dark matter environments of the Milky Way. For axions, we investigate their indirect signatures in two settings: topological defects known as axion strings, and astrophysical environments with abundant axion production, such as core-collapse supernovae. We show that axion strings can deposit a fraction of their energy into Standard Model particles, leading to observable effects in cosmological data such as the cosmic microwave background and big bang nucleosynthesis. In high-production environments, we explore the potential for axion indirect detection through axion-photon conversion in magnetic fields or through the decay of heavier axions. By combining observational data with theoretical modeling, we derive new limits from the non-observation of a signal and demonstrate the power of indirect detection in the search for physics beyond the Standard Model
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Constraining axion dark matter with Big Bang Nucleosynthesis
Full text linkAbstractWe show that Big Bang Nucleosynthesis (BBN) significantly constrains axion-like dark matter. The axion acts like an oscillating QCD θ angle that redshifts in the early Universe, increasing the neutron–proton mass difference at neutron freeze-out. An axion-like particle that couples too strongly to QCD results in the underproduction of He4 during BBN and is thus excluded. The BBN bound overlaps with much of the parameter space that would be covered by proposed searches for a time-varying neutron EDM. The QCD axion does not couple strongly enough to affect BBN
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Upper limit on the axion-photon coupling from magnetic white dwarf polarization
Full text linkPolarization measurements of thermal radiation from magnetic white dwarf
(MWD) stars have been proposed as a probe of axion-photon mixing. The radiation
leaving the surface of the MWD is unpolarized, but if low-mass axions exist
then photons polarized parallel to the direction of the MWD's magnetic field
may convert into axions, which induces a linear polarization dependent on the
strength of the axion-photon coupling . We model this
process by using the formalism of axion-photon mixing in the presence of
strong-field vacuum birefringence to show that of all stellar types MWDs are
the most promising targets for axion-induced polarization searches. We then
consider linear polarization data from multiple MWDs, including SDSS J135141
and Grw+708247, to show that after rigorously accounting for
astrophysical uncertainties the axion-photon coupling is constrained to
GeV at 95% confidence
for axion masses eV. This upper limit puts in
tension the previously-suggested explanation of the anomalous transparency of
the Universe to TeV gamma-rays in terms of axions. We identify MWD targets for
which future data and modeling efforts could further improve the sensitivity to
axions.Comment: 22 pages, 9 figure
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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