Thick disk evolution is studied using edge-on galaxies in two Hubble Space Telescope Frontier Field Parallels. The galaxies were separated into 72 clumpy types and 35 spiral types with bulges. Perpendicular light profiles in F435W, F606W and F814W (B, V and I) passbands were measured at 1 pixel intervals along the major axes and fitted to sech 2 functions convolved with the instrument line spread function (LSF). The LSF was determined from the average point spread function (PSF) of ∼ 20 stars in each passband and field, convolved with a line of uniform brightness to simulate disk blurring. A spread function for a clumpy disk was also used for comparison. The resulting scale heights were found to be proportional to galactic mass, with the average height for a 10 10±0.5 M galaxy at z = 2 ± 0.5 equal to 0.63 ± 0.24 kpc. This value is probably the result of a blend between thin and thick disk components that cannot be resolved. Evidence for such two-component structure is present in an inverse correlation between height and midplane surface brightness. Models suggest that the thick disk is observed best between the clumps, and there the average scale height is 1.06 ± 0.43 kpc for the same mass and redshift. A 0.63 ± 0.68 mag V-I color differential with height is also evidence for a mixture of thin and thick components.
We study the imprint of higher spin supermultiplets on cosmological correlators, namely the non-Gaussianity of the cosmic microwave background. Supersymmetry is used as a guide to introduce the contribution of fermionic higher spin particles, which have been neglected thus far in the literature. This necessarily introduces more than just a single additional fermionic superpartner, since the spectrum of massive, higher spin supermultiplets includes two propagating higher spin bosons and two propagating higher spin fermions, which all contribute to the three point function. As an example we consider the half-integer superspin Y = s + 1/2 supermultiplet, which includes particles of spin values j = s + 1, j = s + 1/2, j = s + 1/2 and j = s. We compute the curvature perturbation 3-point function for higher spin particle exchange and find that the known P s (cos θ) angular dependence is accompanied by superpartner contributions that scale as P s+1 (cos θ) and m P m s (cos θ), with P s and P m s defined as the Legendre and Associated Legendre polynomials respectively. We also compute the tensor-scalar-scalar 3-point function, and find a complicated angular dependence as an integral over products of Legendre and associated Legendre polynomials.
The quasar 3C454.3 underwent a uniquely-structured multi-frequency outburst in June 2016. The blazar was observed in the optical R band by several ground-based telescopes in photometric and polarimetric modes, at γ-ray frequencies by the Fermi Large Area Telescope, and at 43 GHz with the Very Long Baseline Array. The maximum flux density was observed on 2016 June 24 at both optical and γ-ray frequencies, reaching S max opt = 18.91 ± 0.08 mJy and S max γ = 22.20 ± 0.18 × 10 −6 ph cm −2 s −1 , respectively. The June 2016 outburst possessed a precipitous decay at both γ-ray and optical frequencies, with the source decreasing in flux density by a factor of 4 over a 24-hour period in R band. Intraday variability was observed throughout the outburst, with flux density changes between 1 and 5 mJy over the course of a night. The precipitous decay featured statistically significant quasi-periodic micro-variability oscillations with an amplitude of ∼ 2-3% about the mean trend and a characteristic period of 36 minutes. The optical degree of polarization jumped from ∼ 3% to nearly 20% during the outburst, while the position angle varied by ∼ 120 • . A knot was ejected from the 43 GHz core on 2016 Feb 25, moving at an apparent speed v app = 20.3c ± 0.8c. From the observed minimum timescale of variability τ min opt ≈ 2 hr and derived Doppler factor δ = 22.6, we find a size of the emission region r 2.6 × 10 15 cm. If the quasi-periodic micro-variability oscillations are caused by periodic variations of the Doppler factor of emission from a turbulent vortex, we derive a rotational speed of the vortex ∼ 0.2c.
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