Nanoflare Activity in the Solar Chromosphere

We use ground-based images of high spatial and temporal resolution to search for evidence of nanoflare activity in the solar chromosphere. Through close examination of more than 10^9 pixels in the immediate vicinity of an active region, we show that the distributions of observed intensity fluctuations have subtle asymmetries. A negative excess in the intensity fluctuations indicates that more pixels have fainter-than-average intensities compared with those that appear brighter than average. By employing Monte Carlo simulations, we reveal how the negative excess can be explained by a series of impulsive events, coupled with exponential decays, that are fractionally below the current resolving limits of low-noise equipment on high-resolution ground-based observatories. Importantly, our Monte Carlo simulations provide clear evidence that the intensity asymmetries cannot be explained by photon-counting statistics alone. A comparison to the coronal work of Terzo et al. (2011) suggests that nanoflare activity in the chromosphere is more readily occurring, with an impulsive event occurring every ~360s in a 10,000 km^2 area of the chromosphere, some 50 times more events than a comparably sized region of the corona. As a result, nanoflare activity in the chromosphere is likely to play an important role in providing heat energy to this layer of the solar atmosphere.Comment: 7 pages, 3 figures, accepted into Ap

Cacophony is Music to our Minds

The clarity of a single note played beautifully can be a highlight of a musical performance. Jason, Stevens, Ram, Beasley and Gleason (2016) do us a service by reminding us of the distilled clarity that arises from a pure note played well in community psychology. In science this can includes theory-based predictions that are tested and affirmed, or tested and either discarded or improved. Such clear moments can be uncommon and are special instances of scientific progress. Seeking such clarity of theory is important in advancing science. On the other hand, in my first year of college, an insightful music major commented that the history of progress in music appreciation is the story of listeners learning to appreciate new forms of dissonance. Science is music to the ears and minds of researchers and is about many things. Developing theory-based predictions that enable us to predict and control is an important one, but only one of many, as Jason and his colleagues (2016) note. For this brief comment I focus primarily on generativity as a one of several valuable functions of scientific theory that is given little attention by some of the sources Jason and colleagues cite in defense of their position

Cacophony is Music to our Minds

The clarity of a single note played beautifully can be a highlight of a musical performance. Jason, Stevens, Ram, Beasley and Gleason (2016) do us a service by reminding us of the distilled clarity that arises from a pure note played well in community psychology. In science this can includes theory-based predictions that are tested and affirmed, or tested and either discarded or improved. Such clear moments can be uncommon and are special instances of scientific progress. Seeking such clarity of theory is important in advancing science. On the other hand, in my first year of college, an insightful music major commented that the history of progress in music appreciation is the story of listeners learning to appreciate new forms of dissonance. Science is music to the ears and minds of researchers and is about many things. Developing theory-based predictions that enable us to predict and control is an important one, but only one of many, as Jason and his colleagues (2016) note. For this brief comment I focus primarily on generativity as a one of several valuable functions of scientific theory that is given little attention by some of the sources Jason and colleagues cite in defense of their position

Creating community life among immigrant survivors of torture and their allies

This qualitative study describes how immigrant survivors of torture in the United States built relationships among each other to form a psychological sense of community. Eight men and seven women from 11 different countries were recruited through a torture treatment center and a survivor-led advocacy and support coalition. This qualitative study explored how participants described their experiences of community life. An advisory group that included torture survivors, torture treatment practitioners, abolition advocates, and academic experts guided the study. Data was analyzed using inductive and phenomenological theories. The construct of psychological sense of community articulated by McMillan and Chavis1 provided the conceptual framework for the evaluation of how a psychological sense of community was developed. Torture survivors with their allies formed community boundaries based on a deep understanding of the impact of torture. The safety afforded through the community boundaries was reinforced by shared condemnation of torture in all circumstances. Within the security of the community’s boundaries, members shared their experiences to enable their own and others’ recovery from torture. As community members exchanged advice and support, survivors met one another’s needs, providing physical and emotional relief from the effects of their torture. As individuals and a community, they influenced each other’s identities as survivors rather than victims. Advocating for those who remained vulnerable to torture was important to their identification as survivors. Through these exchanges, community members influenced one another and developed trusting relationships and emotional bonds. This study illuminates how community life enabled survivors to contribute to and benefit from, each other’s journeys

Propagating Wave Phenomena Detected in Observations and Simulations of the Lower Solar Atmosphere

We present high-cadence observations and simulations of the solar photosphere, obtained using the Rapid Oscillations in the Solar Atmosphere imaging system and the MuRAM magneto-hydrodynamic code, respectively. Each dataset demonstrates a wealth of magneto-acoustic oscillatory behaviour, visible as periodic intensity fluctuations with periods in the range 110-600 s. Almost no propagating waves with periods less than 140s and 110s are detected in the observational and simulated datasets, respectively. High concentrations of power are found in highly magnetised regions, such as magnetic bright points and intergranular lanes. Radiative diagnostics of the photospheric simulations replicate our observational results, confirming that the current breed of magneto-hydrodynamic simulations are able to accurately represent the lower solar atmosphere. All observed oscillations are generated as a result of naturally occurring magnetoconvective processes, with no specific input driver present. Using contribution functions extracted from our numerical simulations, we estimate minimum G-band and 4170 Angstrom continuum formation heights of 100 km and 25 km, respectively. Detected magneto-acoustic oscillations exhibit a dominant phase delay of -8 degrees between the G-band and 4170 Angstrom continuum observations, suggesting the presence of upwardly propagating waves. More than 73% of MBPs (73% from observations, 96% from simulations) display upwardly propagating wave phenomena, suggesting the abundant nature of oscillatory behaviour detected higher in the solar atmosphere may be traced back to magnetoconvective processes occurring in the upper layers of the Sun's convection zone.Comment: 13 pages, 9 figures, accepted into Ap

Toward the future: A conceptual review and call for research and action with online communities

The internet allows people to connect with virtually anyone across the globe, building communities based on shared interests, experiences, and goals. Despite the potential for furthering our understanding of communities more generally through exploring them in online contexts, online communities have not generally been a focus of community psychologists. A conceptual, state-of-the-art review of eight major community psychology journals revealed 23 descriptive or empirical articles concerning online communities have been published in the past 20 years. These articles are primarily descriptive and can be organized into four categories: community building and maintenance (seven articles, 30.43%), community support (six articles, 26.09%), norms and attitudes (six articles, 26.09%), and advocacy (four articles, 17.39%). These articles reflect a promising start to understanding how we can utilize the internet to build and enhance communities. They also indicate how much further we have to go, both in understanding online communities and certain concepts regarding community psychology more generally. Community psychologists involved in practice and applied settings specifically may benefit from understanding online communities as they become integral components of advocacy, community organizing, and everyday life

The Velocity Distribution of Solar Photospheric Magnetic Bright Points

We use high spatial resolution observations and numerical simulations to study the velocity distribution of solar photospheric magnetic bright points. The observations were obtained with the Rapid Oscillations in the Solar Atmosphere instrument at the Dunn Solar Telescope, while the numerical simulations were undertaken with the MURaM code for average magnetic fields of 200 G and 400 G. We implemented an automated bright point detection and tracking algorithm on the dataset, and studied the subsequent velocity characteristics of over 6000 structures, finding an average velocity of approximately 1 km/s, with maximum values of 7 km/s. Furthermore, merging magnetic bright points were found to have considerably higher velocities, and significantly longer lifetimes, than isolated structures. By implementing a new and novel technique, we were able to estimate the background magnetic flux of our observational data, which is consistent with a field strength of 400 G.Comment: Accepted for publication in ApJL, 12 pages, 2 figure