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Observations of the redshift z = 7.085 quasar J1120+0641 are used to search for variations of the fine structure constant, a, over the redshift range 5:5 to 7:1. Observations at z = 7:1 probe the physics of the universe at only 0.8 billion years old. These are the most distant direct measurements of a to date and the first measurements using a near-IR spectrograph. A new AI analysis method is employed. Four measurements from the x-shooter spectrograph on the Very Large Telescope (VLT) constrain changes in a relative to the terrestrial value (α0). The weighted mean electromagnetic force in this location in the universe deviates from the terrestrial value by Δα/α = (αz − α0)/α0 = (−2:18 ± 7:27) × 10−5, consistent with no temporal change. Combining these measurements with existing data, we find a spatial variation is preferred over a no-variation model at the 3:9σ level.

The Global Network of Optical Magnetometers to search for Exotic physics (GNOME) is a network of geographically separated, time-synchronized, optically pumped atomic magnetometers that is being used to search for correlated transient signals heralding exotic physics. The GNOME is sensitive to nuclear-and electron-spin couplings to exotic fields from astrophysical sources such as compact dark-matter objects (for example, axion stars and domain walls). Properties of the GNOME sensors such as sensitivity, bandwidth, and noise characteristics are studied in the present work, and features of the network's operation (e.g., data acquisition, format, storage, and diagnostics) are described. Characterization of the GNOME is a key prerequisite to searches for and identification of exotic physics signatures.

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We report the detection of neutral deuterium in the low-metallicity damped Lyman-α system at z abs = 2.621 towards the quasar CTQ 247. Using a high signal-to-noise and high spectral resolution (R = 60 000) spectrum from the Very Large Telescope Ultraviolet and Visual Echelle Spectrograph, we precisely measure the deuterium-to-oxygen ratio log N(D i)/N(O i) = 0.74 ± 0.04, as well as the overall oxygen abundance, log N(O i)/N(H i) = −5.30 ± 0.10 (or equivalently [O/H] = −1.99 ± 0.10 with respect to the solar value). Assuming uniform metallicity throughout the system, our measurement translates into (D/H) = (2.8−5 . This ratio is consistent within errors (<0.4σ) with the primordial ratio, (D/H) p = (2.59 ± 0.15) × 10 −5 , predicted by standard Big-Bang nucleosynthesis using the WMAP7 value of the cosmological density of baryons (100 Ω b h 2 = 2.249 ± 0.056). The D i absorption lines are observed to be broader than the O i absorption lines. From a consistent fit of the profiles we derive the turbulent broadening to be 5.2 km s −1 and the temperature of the gas to be T = 8800 ± 1500 K, corresponding to a warm neutral medium.