2 research outputs found

    UV/Optical disk reverberation lags despite a faint X-ray corona in the AGN Mrk 335

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    We present the first results from a 100-day Swift, NICER and ground-based X-ray/UV/optical reverberation mapping campaign of the Narrow-Line Seyfert 1 Mrk 335, when it was in an unprecedented low X-ray flux state. Despite dramatic suppression of the X-ray variability, we still observe UV/optical lags as expected from disk reverberation. Moreover, the UV/optical lags are consistent with archival observations when the X-ray luminosity was >10 times higher. Interestingly, both low- and high-flux states reveal UV/optical lags that are 6-11 times longer than expected from a thin disk. These long lags are often interpreted as due to contamination from the broad line region, however the u band excess lag (containing the Balmer jump from the diffuse continuum) is less prevalent than in other AGN. The Swift campaign showed a low X-ray-to-optical correlation (similar to previous campaigns), but NICER and ground-based monitoring continued for another two weeks, during which the optical rose to the highest level of the campaign, followed ~10 days later by a sharp rise in X-rays. While the low X-ray countrate and relatively large systematic uncertainties in the NICER background make this measurement challenging, if the optical does lead X-rays in this flare, this indicates a departure from the zeroth-order reprocessing picture. If the optical flare is due to an increase in mass accretion rate, this occurs on much shorter than the viscous timescale. Alternatively, the optical could be responding to an intrinsic rise in X-rays that is initially hidden from our line-of-sight.Comment: Accepted for publication in the Astrophysical Journal. 15 pages, 8 figures, 3 table

    Components of engagement in saying-is-believing exercises.

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    The saying-is-believing effect is an important step for changing students' attitudes and beliefs in a wise intervention. However, most studies have not closely examined the process of the saying-is-believing effect when individuals are engaged in the activity. Using a qualitative approach, the present study uses an engagement framework to investigate (a) components of engagement in the saying-is-believing effect; and (b) how differently students may engage in a saying-is-believing exercise. Semi-structured interviews were conducted with 14 undergraduates in a scholarship program for low-income transfer students from community college. Analysis using inductive and deductive approaches found that students varied on the extent to which they experienced the effectiveness of the saying-is-believing effect through affective, cognitive, and behavioral experiences. The study offers examples of how people can indeed differ in the extent to which they experience the saying-is-believing effect, and the implications for designing more effective interventions. Specifically, students' positive affective experiences from seeing the larger goal of creating videos may be important components for the saying-is-believing effect to work. Behavioral experiences, such as learning soft skills, academic skills learned indirectly from the intervention, and academic skills learned directly from the intervention were accompanied by both positive affective and cognitive experiences. Findings show the importance of students' differential engagement in saying-is-believing exercises both for building more effective wise interventions and interpreting heterogeneity in intervention effectiveness
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