Time Dependence of the electron and positron components of the cosmic radiation measured by the PAMELA experiment between July 2006 and December 2015

Cosmic-ray electrons and positrons are a unique probe of the propagation of cosmic rays as well as of the nature and distribution of particle sources in our Galaxy. Recent measurements of these particles are challenging our basic understanding of the mechanisms of production, acceleration, and propagation of cosmic rays. Particularly striking are the differences between the low energy results collected by the space-borne PAMELA and AMS-02 experiments and older measurements pointing to sign-charge dependence of the solar modulation of cosmic-ray spectra. The PAMELA experiment has been measuring the time variation of the positron and electron intensity at Earth from July 2006 to December 2015 covering the period for the minimum of solar cycle 23 (2006-2009) until the middle of the maximum of solar cycle 24, through the polarity reversal of the heliospheric magnetic field which took place between 2013 and 2014. The positron to electron ratio measured in this time period clearly shows a sign-charge dependence of the solar modulation introduced by particle drifts. These results provide the first clear and continuous observation of how drift effects on solar modulation have unfolded with time from solar minimum to solar maximum and their dependence on the particle rigidity and the cyclic polarity of the solar magnetic field

“I decided to teach… despite the anger”: using forum theatre to connect queer activists, teachers and school leaders to address heterosexism in schools

While South Africa’s transition to democracy was filled with promises of transformation in education and access to all South Africans, these promises are met by the reality of lasting and entrenched inequality. Schools remain defined by racism, sexism, and heterosexism. Regarding heterosexism, while there are many challenges; opportunities for dialogue and social change are emerging. This chapter explores the way school administrators, teachers, and queer activists connect to address heterosexism. Specifically, it addresses a critical question—what happens when queer activists, teachers, and school managers are brought together using the democratic dialogic process of Freire together with Augusto Boal’s Forum Theatre to address heterosexism in schools? The chapter argues that art-based methods not only offer a structure for dealing with complex and challenging conversation that may arise but is a constructive platform to create sketches that show what anti-heterosexist and inclusive schools for LGBTI learners might look like