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The Planck All-Sky Survey to Analyze Gravitationally-lensed Extreme Starbursts project aims to identify a population of extremely luminous galaxies using the Planck all-sky survey and to explore the nature of their gas fuelling, induced starburst, and the resulting feedback that shape their evolution. Here, we report the identification of 22 high-redshift luminous dusty star-forming galaxies (DSFGs) at z = 1.1–3.3 drawn from a candidate list constructed using the Planck Catalogue of Compact Sources and Wide-field Infrared Survey Explorer all-sky survey. They are confirmed through follow-up dust continuum imaging and CO spectroscopy using AzTEC and the Redshift Search Receiver on the Large Millimeter Telescope Alfonso Serrano. Their apparent infrared luminosities span (0.1–3.1) × 1014 L⊙ (median of 1.2 × 1014 L⊙), making them some of the most luminous galaxies found so far. They are also some of the rarest objects in the sky with a source density of ≲0.01 deg−2. Our Atacama Large Millimeter/submillimeter Array 1.1 mm continuum observations with θ ≈ 0.4 arcsec resolution show clear ring or arc morphologies characteristic of strong lensing. Their lensing-corrected luminosity of LIR ≳ 1013 L⊙ (star-formation rate ≳ 103 M⊙ yr−1) indicates that they are the magnified versions of the most intrinsically luminous DSFGs found at these redshifts. Our spectral energy distribution analysis finds little detectable active galactic nucleus (AGN) activity despite their enormous luminosity, and any AGN activity present must be extremely heavily obscured.

The present work is a comprehensive study of the ionospheric vertical total electron content (vTEC) variations during the nighttime, based on data collected by ground‐based Global Navigation Satellite System (GNSS) receivers over the Latin American region. We provide a qualitative and quantitative analysis of the ionospheric vTEC trend at 21:00, 00:00, and 03:00 local time (LT), during geomagnetically undisturbed days of 2011 (ascending phase) and 2014 (maximum phase), which encompassed (a) the response to the solar flux variation, (b) the seasonal trend in different latitudes and longitudes, and (c) the interhemispheric asymmetry. One significant result of this study is the development of TEC maps for the Latin American region, which are used for the monitoring and forecasting of the ionosphere for space weather purposes. The nighttime vTEC variations showed a strong latitudinal dependence, especially in the Northern Hemisphere. For 2011, the semiannual anomaly was similar to that observed in daytime; however, in 2014, the receivers at midlatitude presented asymmetric behavior. Similarly, the nighttime winter anomaly (NWA) was very weak in both years. The Equatorial Ionospheric Anomaly (EIA) signature was absent from June to August, a period in which the hemispheric disparity in the vTEC values became more evident, suggesting a feeble interhemispheric circulation. The Midlatitude Summer Nighttime Anomaly (MSNA) was also identified in the Southern Hemisphere, during January and February of 2011 (moderate solar activity). Model approximations suggest that the equatorward winds and the EIA were involved in the formation of the MSNA.