3 research outputs found

    Tapped Out: Threats to the Human Right to Water in the Urban United States

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    In the United States today, the goal of universal water service is slipping out of reach. Water costs are rising across the country, forcing many individuals to forgo running water or sanitation, or to sacrifice other essential human rights. The fixed costs of water systems have increased in recent years, driven in part by underinvestment in infrastructure. In many cities, this has been exacerbated by population shifts and the economic downturn. In this era of increasing costs and limited financial resources, water providers struggle to balance the competing priorities of modernization and universal access. This report, researched and written by students of Georgetown Law’s Human Rights Institute in the winter of 2013, details the causes, effects, and solutions to the affordability crisis affecting water in the urban United States

    Near-Infrared Photometry of the Type IIn SN 2005ip: The Case for Dust Condensation

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    Near-infrared photometric observations of the Type IIn SN 2005ip in NGC 2906 reveal large fluxes (>1.3 mJy) in the K_s-band over more than 900 days. While warm dust can explain the late-time K_s-band emission of SN 2005ip, the nature of the dust heating source is ambiguous. Shock heating of pre-existing dust by post-shocked gas is unlikely because the forward shock is moving too slowly to have traversed the expected dust-free cavity by the time observations first reveal the K_s emission. While an infrared light echo model correctly predicts a near-infrared luminosity plateau, heating dust to the observed temperatures of ~1400-1600 K at a relatively large distance from the supernova (> 10^{18} cm) requires an extraordinarily high early supernova luminosity (~1 X 10^{11} L_solar). The evidence instead favors condensing dust in the cool, dense shell between the forward and reverse shocks. Both the initial dust temperature and the evolutionary trend towards lower temperatures are consistent with this scenario. We infer that radiation from the circumstellar interaction heats the dust. While this paper includes no spectroscopic confirmation, the photometry is comparable to other SNe that do show spectroscopic evidence for dust formation. Observations of dust formation in SNe are sparse, so these results provide a rare opportunity to consider SNe Type IIn as dust sources.Comment: 11 pages, 6 figures, 3 tables, Accepted for Publication to ApJ: January 20, 200
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