Antiproton and Positron Signal Enhancement in Dark Matter Mini-Spikes Scenarios

The annihilation of dark matter (DM) in the Galaxy could produce specific imprints on the spectra of antimatter species in Galactic cosmic rays, which could be detected by upcoming experiments such as PAMELA and AMS02. Recent studies show that the presence of substructures can enhance the annihilation signal by a "boost factor" that not only depends on energy, but that is intrinsically a statistical property of the distribution of DM substructures inside the Milky Way. We investigate a scenario in which substructures consist of $\sim 100$ "mini-spikes" around intermediate-mass black holes. Focusing on primary positrons and antiprotons, we find large boost factors, up to a few thousand, that exhibit a large variance at high energy in the case of positrons and at low energy in the case of antiprotons. As a consequence, an estimate of the DM particle mass based on the observed cut-off in the positron spectrum could lead to a substantial underestimate of its actual value.Comment: 13 pages, 9 figures, minor changes, version accepted for publication in PR

Clinician experiences on training and awareness of sexual orientation in NHS Talking Therapies Services for Anxiety and Depression

Previous research that explored sexual minority service users’ experiences of accessing NHS Talking Therapies for Anxiety and Depression Services highlighted the need for specific sexual orientation training. Inconsistent or lack of training may contribute to disparities in treatment outcomes between sexual minority service users and heterosexual service users. The aim of the study was to explore clinicians’ competencies working with sexual minority service users, their experiences of sexual orientation training, their view of current gaps intraining provision, and ways to improve training. Self-reported sexual orientation competency scales and open ended questions were used to address the aims of the study. Participants (n=83) included Psychological Wellbeing Practitioners (PWPs) and high-intensity CBT therapists (HITs). Responses on competency scales were analysed using Kruskal–Wallis tests and thematic analysis was used to analyse qualitative responses. Participants who identified as 25–29 years old had higher scores on the knowledge scale than 45+-year-olds.Bisexual participants also had higher scores on the knowledge subscale than heterosexual participants. Threeover-arching themes were identified: (a) training received on sexual minority issues by Talking Therapies clinicians, (b) clinicians’ experiences of accessing and receiving sexual minority training, and (c) perceived gaps in current sexual minority training and ways to improve training. Findings were linked to previous literature and recommendations to stakeholders are made throughout the Discussion section with the view of improving sexual orientation training

'Datafication': Making sense of (big) data in a complex world

This is a pre-print of an article published in European Journal of Information Systems. The definitive publisher-authenticated version is available at the link below. Copyright @ 2013 Operational Research Society Ltd.No abstract available (Editorial

Associations and the exercise of citizenship in new democracies : evidence from São Paulo and Mexico City

A well-established body of democratic theory suggests that associations are the schools of democracy and, because they produce civic and active citizens, are vital to the quality of democracy. In this paper we find that this may not be the case in newer democracies with authoritarian legacies. Survey research in the large urban centers of São Paulo and Mexico City reveals that citizens who participate in associations are more likely to actively pursue a range of rights and entitlements, but this participation does not improve the quality of their relations with government. Participation in associations does not make it more likely that an individual has the type of direct relations to government that approximate the democratic ideal, and that suggests that public officials treat citizens as legal equals and carriers of rights and entitlements. Instead, associations are as likely to reinforce the detached, brokered, or contentious relations to government that are common in newer democracies and vary in their distance from the democratic ideal. Rather than focus on voting behaviour or partisan activities, we explore the civil component of active citizenship that operates when citizens’ seek access to the public goods necessary for enjoyment of the rights and entitlements constitutive of contemporary citizenship. Keywords: associations; citizenship; citizens; democratic theory; inequality; rule of law; political participatio

In whose name? : political representation and civil organisations in Brazil

There is now considerable evidence that civil organisations have become de facto and de jure representatives of particular segments of the population and interests in the design, implementation, and monitoring of public policy. This paper explores two questions that are becoming increasingly important in the debate on the role of “civil society” in contemporary democracy: Who do civil organisations represent when they act as representatives in the polity; and, in what terms is this representation constructed? The role of civil organisations in political representation has received little or no attention in the research agendas on the reconfiguration of representation or on the democratising of democracy. Furthermore, there are no wellestablished theoretical models beyond the classic electoral or membership ones which set out how civil organisations could establish their representativeness. The vast majority of civil organisations in middleand low-income countries, however, are not membership based and few make use of electoral procedures to authorise a mandate or establish accountability. This paper examines which organisations define themselves as political representatives and the forms of representation they are constructing. It also explores some of the possible consequences of different forms of representation for democracy. The paper draws on findings of a survey of civil organisations – that is, neighbourhood or community associations, membership organisations, NGOs, and coordinators of networks of these organisations – in the city of São Paulo, Brazil. We find that organisations that publicly claim to be representatives of particular publics in fact do engage in extensive representation activities; and, that the dynamics of representation among civil organisations are closely related to those of traditional political channels of representation. Furthermore, we find that the congruency arguments civil organisations make publicly to support their representativeness are crystallising around a small number of notions of representation. The most common are mediation, proximity, and services. The least common are identity, electoral, and membership

Who participates? : civil society and the new democratic politics in São Paulo, Brazil

This paper explores the participation of collective civil society actors in institutional spaces for direct citizen participation in the city of São Paulo, Brazil. The data was produced by a unique survey of civil society actors who work for, or with, sectors of the lower-middle class, the working class, and the urban poor. The paper identifies factors that influence the propensity of civil society actors to participate in three types of institutions: the participatory budget, the constitutionally mandated policy councils, and other local participatory councils and programmes. Many political leaders, policy-makers and researchers believe that such forms of direct citizen participation can help democratise and rationalise the state, as well as provide politically marginalised populations with a say in policy. Whether these hopes materialise depends in part on the answer(s) to a question the literatures on civil society, citizen participation and empowered participation have not addressed – Who Participates? Contrary to the focus on autonomy in much of the work on civil society, the statistical findings support the claim that collective actors with relations to institutional actors, and the Workers’ Party and State actors in particular, have the highest propensity to participate. The findings also support the idea that the institutional design of participatory policy-making spaces has a significant impact on who participates, and that this impact varies by type of civil society actor. Unlike what has been found in research on individual citizen participation, there is no evidence that the “wealth” of collective actors influences participation

Galactic secondary positron flux at the Earth

Secondary positrons are produced by spallation of cosmic rays within the interstellar gas. Measurements have been typically expressed in terms of the positron fraction, which exhibits an increase above 10 GeV. Many scenarios have been proposed to explain this feature, among them some additional primary positrons originating from dark matter annihilation in the Galaxy. The PAMELA satellite has provided high quality data that has enabled high accuracy statistical analyses to be made, showing that the increase in the positron fraction extends up to about 100 GeV. It is therefore of paramount importance to constrain theoretically the expected secondary positron flux to interpret the observations in an accurate way. We find the secondary positron flux to be reproduced well by the available observations, and to have theoretical uncertainties that we quantify to be as large as about one order of magnitude. We also discuss the positron fraction issue and find that our predictions may be consistent with the data taken before PAMELA. For PAMELA data, we find that an excess is probably present after considering uncertainties in the positron flux, although its amplitude depends strongly on the assumptions made in relation to the electron flux. By fitting the current electron data, we show that when considering a soft electron spectrum, the amplitude of the excess might be far lower than usually claimed. We provide fresh insights that may help to explain the positron data with or without new physical model ingredients. PAMELA observations and the forthcoming AMS-02 mission will allow stronger constraints to be aplaced on the cosmic--ray transport parameters, and are likely to reduce drastically the theoretical uncertainties.Comment: 15 pages, 12 figures. The recent PAMELA data on the positron fraction (arXiv:0810.4995) have been included and the ensuing discussion has been extended. Accepted version in A&

Antimatter signals of singlet scalar dark matter

We consider the singlet scalar model of dark matter and study the expected antiproton and positron signals from dark matter annihilations. The regions of the viable parameter space of the model that are excluded by present data are determined, as well as those regions that will be probed by the forthcoming experiment AMS-02. In all cases, different propagation models are investigated, and the possible enhancement due to dark matter substructures is analyzed. We find that the antiproton signal is more easily detectable than the positron one over the whole parameter space. For a typical propagation model and without any boost factor, AMS-02 will be able to probe --via antiprotons-- the singlet model of dark matter up to masses of 600 GeV. Antiprotons constitute, therefore, a promising signal to constraint or detect the singlet scalar model.Comment: 24 pages, 8 figures. v2: minor improvements. Accepted for publication in JCA

Cosmic-ray antiproton constraints on light dark matter candidates

Some direct detection experiments have recently collected excess events that could be interpreted as a dark matter (DM) signal, pointing to particles in the $\sim$10 GeV mass range. We show that scenarios in which DM can self-annihilate with significant couplings to quarks are likely excluded by the cosmic-ray (CR) antiproton data, provided the annihilation is S-wave dominated when DM decouples in the early universe. These limits apply to most of supersymmetric candidates, eg in the minimal supersymmetric standard model (MSSM) and in the next-to-MSSM (NMSSM), and more generally to any thermal DM particle with hadronizing annihilation final states.Comment: Contribution to the proceedings of TAUP-2011 (Munich, 5-9 IX 2011). 4 page