1,721,069 research outputs found
Particle Dark Matter constraints: The effect of Galactic uncertainties
No full textCollider, space, and Earth based experiments are now able to probe several extensions of the Standard Model of particle physics which provide viable dark matter candidates. Direct and indirect dark matter searches rely on inputs of astrophysical nature, such as the local dark matter density or the shape of the dark matter density profile in the target in object. The determination of these quantities is highly affected by astrophysical uncertainties. The latter, especially those for our own Galaxy, are ill-known, and often not fully accounted for when analyzing the phenomenology of particle physics models. In this paper we present a systematic, quantitative estimate of how astrophysical uncertainties on Galactic quantities (such as the local galactocentric distance, circular velocity, or the morphology of the stellar disk and bulge) propagate to the determination of the phenomenology of particle physics models, thus eventually affecting the determination of new physics parameters. We present results in the context of two specific extensions of the Standard Model (the Singlet Scalar and the Inert Doublet) that we adopt as case studies for their simplicity in illustrating the magnitude and impact of such uncertainties on the parameter space of the particle physics model itself. Our findings point toward very relevant effects of current Galactic uncertainties on the determination of particle physics parameters, and urge a systematic estimate of such uncertainties in more complex scenarios, in order to achieve constraints on the determination of new physics that realistically include all known uncertainties
Bounds on axionlike particles from the diffuse supernova flux
Full text linkThe cumulative emission of axionlike particles (ALPs) from all past core-collapse supernovae (SNe) would lead to a diffuse flux with energies O(50) MeV. We use this to constrain ALPs featuring couplings to photons and to nucleons. ALPs coupled only to photons are produced in the SN core via the Primakoff process and then converted into gamma rays in the Galactic magnetic field. We set a bound on gaγ≲5×10-10 GeV-1 for ma≲10-11 eV, using recent measurements of the diffuse gamma-ray flux observed by the Fermi-LAT telescope. However, if ALPs couple also with nucleons, their production rate in SN can be considerably enhanced due to the ALPs nucleon-nucleon bremsstrahlung process. Assuming the largest ALP-nucleon coupling phenomenologically allowed, bounds on the diffuse gamma-ray flux lead to a much stronger gaγ≲6×10-13 GeV-1 for the same mass range. If ALPs are heavier than ∼keV, the decay into photons becomes significant, leading again to a diffuse gamma-ray flux. In the case of only photon coupling, we find, e.g., gaγ≲5×10-11 GeV-1 for ma∼5 keV. Allowing for a (maximal) coupling to nucleons, the limit improves to the level of gaγ≲10-19 GeV-1 for ma∼20 MeV, which represents the strongest constraint to date
Erratum: Particle Dark Matter constraints: the effect of Galactic uncertainties (Journal of Cosmology and Astroparticle Physics DOI: 10.1088/1475-7516/2017/02/007)
No full textThis erratum corrects the following mistakes in our paper Particle Dark Matter Constraints: the Effect of Galactic Uncertainties: values of the stellar mass of the Milky Way (MW) in column 4 of table 1, values of the total MW mass quoted in text, and a typo when referring to the value of the total MW as quoted in the Sagittarius stream paper [1]. Here we provide a correct version of table 1 (stellar mass of the MW corrected, column 4), and replace the final, corrected version of the text (original lines below table 1 in page 5). No other element of the paper has changed, and conclusions are unaffected. 1.1 Changes: When varying Galactic parameters, we obtain the total mass of the MW within 50 kpc to be in the range M(< 50 ) = (1.2-22.9) × 1011MȮ. The lower limit is in agreement with previous determinations [1, 11-14], while the larger MW masses we obtain can not be directly compared, as the adopted Galactic Parameters are different than ours. When varying baryonic morphology, the minimum/maximum values obtain are M(< 50 kpc) = 4.36+0.11-0.10 × 1011 MȮ and M(< 50 kpc) = 7.0±0.3 × 1011MȮ. The former value for the variation of morphology is in good agreement with mass estimate from kinematics of globular clusters, satellite galaxies and halo stars [11, 12, 14, 15]. There is, however, a discrepancy at the 1 σ level with the independent determination in [1], that used the Sagittarius stream, and is slightly smaller than the other cited determinations. All our results are in agreement at the 1 σ level with the recent estimate of the dynamical mass [16] within the region of the Galactic bulge, as in the analysis presented in [17]. (Table Presented)
“Civis romana sum”: uno sguardo d’insieme sulla cittadinanza al femminile nella Roma antica
No full textSi paragonano le prerogative della cittadinanza romana in base al genere maschile o femminile. Si delinea la condizione giuridica della donna a Roma e le sue limitazioni rispetto al diritto pubblico e al diritto privato. Tuttavia la cittadinanza romana si trasmette anche attraverso le donne. Inoltre lo statuto delle donne non è statico
Cittadinanza, identità e diritto alla differenza. Quanta ‘cittadinanza’ possiamo dare alla differenza?
No full textIn questo contributo adotto una prospettiva sociologico-giuridica orientata alla teoria costituzionalista del diritto per trattare dell’identità e della differenza delle persone che sono cittadini di una società pluralista retta da un sistema politico democratico-costituzionale. La questione più ampia che viene affrontata è quella dell’integrazione di questo tipo di società mediante il riconoscimento dei suoi membri come cittadini di pieno diritto. Il concetto di ‘cittadinanza’ appare come medium di relazioni tra identità e differenza e rinvia a due distinti significati. Il primo è quello tradizionale, per cui la cittadinanza è simbolo di omogenea appartenenza politico-culturale alla nazione; il secondo è quello che la cittadinanza assume in un contesto politico e sociale pluralista, in cui essa si collega ad una collettività di cittadini, accomunati principalmente (solo) dalla titolarità di diritti e doveri peculiari del loro status. In questa seconda versione, la cittadinanza può essere veicolo di inclusione di cittadini differenti. Qui la cittadinanza rimane estranea a, ma garante de, l’identità individuale e ciò nonostante è veicolo del riconoscimento della dignità della persona/cittadino. Poiché alla persona viene riconosciuto costituzionalmente il diritto alla differenza, bisogna vedere fino a punto può essere garantita la sua diversità
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
- …
