Hannah Shoemaker | Searcharxiv

arXiv2026

A Search for Dust in the Outflow of the HH212 Class 0 Protostellar System

Perhaps the most visually striking phenomenon during star formation is the ejection of material along the direction of the protostar's rotational axis. Observed in the form of molecular outflows and/or atomic jets, these features carry away mass, energy and angular momentum from the system. Given the known dust content of protoplanetary disks, and the energetics of outflows, it has been suggested that it should be possible to lift dust from disks via winds, yet limited observational evidence has been presented in the literature. Any detection of dust within protostellar outflows not only puts constraints on the dust content in outflows, but if a sufficient amount of dust can be removed from the system, the mass budget for planet formation could also be affected. We present re-imaging of archival, multi-frequency dust continuum observations taken with the Atacama Large Millimeter/sub-millimeter Array (ALMA) towards the HH212 protostellar system. We detect an extension in the dust emission, and using multi-frequency data in Bands 7 and 9, we estimate the spectral index of the emitting dust and the dust mass in the wind launching region. We find a small but still significant amount of dust mass coincident with the molecular outflow cavity. This finding is assessed in relation to the hypothesis that the outflow could be capable of transporting dust away from the HH212 protoplanetary disk.

astro-ph.SR↗

arXiv2022

Buying Privacy: User Perceptions of Privacy Threats from Mobile Apps

As technology and technology companies have grown in power, ubiquity, and societal influence, some companies -- and notably some mobile apps -- have come to be perceived as privacy threats. Prior work has considered how various factors impact perceptions of threat, including social factors, political speech, and user-interface design. In this work, we investigate how user-visible context clues impact perceptions about whether a mobile application application poses a privacy threat. We conduct a user study with 2109 users in which we find that users depend on context clues -- such as presence of advertising and occurrence (and timing of payment) -- to determine the extent to which a mobile app poses a privacy threat. We also quantify how accurately user assessments match published data collection practices, and we identify a commonly-held misconception about how payments are processed. This work provides new insight into how users assess the privacy threat posed by mobile apps and into social norms around data collection.

cs.HC↗