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The systematic targeting of extended Ly α emission around high-redshift quasars resulted in the discovery of rare and bright Enormous Ly α Nebulae (ELANe) associated with multiple active galactic nuclei (AGNs). We initiate here “a multiwavelength study of ELAN environments” (AMUSE2) focusing on the ELAN around the z ∼ 3 quasar SDSS J1040+1020, aka the Fabulous ELAN. We report on VLT/HAWK-I, APEX/LABOCA, JCMT/SCUBA-2, SMA/850 ÎĽ m, and ALMA CO(5-4), and 2 mm observations and compare them to previously published VLT/MUSE data. The continuum and line detections enable a first estimate of the star formation rates, dust, stellar, and molecular gas masses in four objects associated with the ELAN (three AGNs and one Ly α emitter), confirming that the quasar host is the most star-forming (star formation rate of ∼500 M ⊙ yrâˆ'1) and massive galaxy (M star ∼ 1011 M ⊙) in the system, and thus can be assumed as central. All four embedded objects have similar molecular gas reservoirs ( M H 2 ∼ 10 10 M ⊙), resulting in short depletion timescales. This fact together with the estimated total dark matter halo mass, M DM = (0.8â€"2) Ă— 1013 M ⊙, imply that this ELAN will evolve into a giant elliptical galaxy. Consistently, the constraint on the baryonic mass budget for the whole system indicates that the majority of baryons should reside in a massive warm/hot reservoir (up to 1012 M ⊙), needed to complete the baryons count. Additionally, we discuss signatures of gas infall on the compact objects as traced by Ly α radiative transfer effects and the evidence for the alignment between the satellites’ spins and their directions to the central. [ABSTRACT FROM AUTHOR]

Submillimeter dust polarization measurements of a sample of 50 star-forming regions, observed with the Submillimeter Array (SMA) and the Caltech Submillimeter Observatory (CSO) covering parsec-scale clouds to milliparsec-scale cores, are analyzed in order to quantify the magnetic field importance. The magnetic field misalignment δ—the local angle between magnetic field and dust emission gradient—is found to be a prime observable, revealing distinct distributions for sources where the magnetic field is preferentially aligned with or perpendicular to the source minor axis. Source-averaged misalignment angles 〈 |δ|〉 fall into systematically different ranges, reflecting the different source-magnetic field configurations. Possible bimodal 〈 |δ|〉 distributions are found for the separate SMA and CSO samples. Combining both samples broadens the distribution with a wide maximum peak at small 〈 |δ|〉 values. Assuming the 50 sources to be representative, the prevailing source-magnetic field configuration is one that statistically prefers small magnetic field misalignments |δ|. When interpreting |δ| together with a magnetohydrodynamics force equation, as developed in the framework of the polarization-intensity gradient method, a sample-based log-linear scaling fits the magnetic field tension-to-gravity force ratio 〈 ΣB〉 versus 〈 |δ|〉 with 〈 ΣB〉 = 0.116 · exp (0.047 · 〈 |δ|〉 ) ± 0.20 (mean error), providing a way to estimate the relative importance of the magnetic field, only based on measurable field misalignments |δ|. The force ratio ΣB discriminates systems that are collapsible on average (〈 ΣB〉 < 1) from other molecular clouds where the magnetic field still provides enough resistance against gravitational collapse (〈 ΣB〉 > 1). The sample-wide trend shows a transition around 〈 |δ|〉 ≈ 45°. Defining an effective gravitational force ∼1 – 〈 ΣB〉 , the average magnetic-field-reduced star formation efficiency is at least a factor of two smaller than the free-fall efficiency. For about one fourth of the sources the average efficiency drops to zero. The force ratio ΣB can further be linked to the normalized mass-to-flux ratio, yielding an estimate for the latter one without the need of field strength measurements. Across the sample, a transition from magnetically supercritical to subcritcal is observed with growing misalignment 〈 |δ|〉 . [ABSTRACT FROM AUTHOR]