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We present measurements of the radial profiles of the mass and galaxy number density around Sunyaev–Zel’dovich (SZ)-selected clusters using both weak lensing and galaxy counts. The clusters are selected from the Atacama Cosmology Telescope Data Release 5 and the galaxies from the Dark Energy Survey Year 3 data set. With signal-to-noise ratio of 62 (45) for galaxy (weak lensing) profiles over scales of about 0.2–20 h-1 Mpc, these are the highest precision measurements for SZ-selected clusters to date. Because SZ selection closely approximates mass selection, these measurements enable several tests of theoretical models of the mass and light distribution around clusters. Our main findings are: (1) The splashback feature is detected at a consistent location in both the mass and galaxy profiles and its location is consistent with predictions of cold dark matter N-body simulations. (2) The full mass profile is also consistent with the simulations. (3) The shapes of the galaxy and lensing profiles are remarkably similar for our sample over the entire range of scales, from well inside the cluster halo to the quasilinear regime. We measure the dependence of the profile shapes on the galaxy sample, redshift, and cluster mass. We extend the Diemer & Kravtsov model for the cluster profiles to the linear regime using perturbation theory and show that it provides a good match to the measured profiles. We also compare the measured profiles to predictions of the standard halo model and simulations that include hydrodynamics. Applications of these results to cluster mass estimation, cosmology, and astrophysics are discussed.

We present measurements of the specific angular momentum |$j_\star$| of 41 star-forming galaxies at |$1.5\lt z\lt 2.5$|⁠. These measurements are based on radial profiles inferred from near-infrared Hubble Space Telescope photometry, along with multiresolution emission-line kinematic modelling using integral field spectroscopy (IFS) data from K -band multi-object spectrograph, Spectrograph for Integral Field Observations in the Near Infrared, and OH-Suppressing Infra-Red Imaging Spectrograph. We identified 24 discs (disc fraction of |$58.6\pm 7.7~{{\ \rm per\ cent}}$|⁠) and used them to parametrize the |$j_\star$| versus stellar mass |$M_\star$| relation (Fall relation) as |$j_\star \propto M_\star ^{\beta }$|⁠. We measure a power-law slope |$\beta =0.25\pm 0.15$|⁠ , which deviates by approximately |$3\sigma$| from the commonly adopted local value |$\beta = 0.67$|⁠ , indicating a statistically significant difference. We find that two key systematic effects could drive the steep slopes in previous high-redshift studies: first, including irregular (non-disc) systems due to limitations in spatial resolution and second, using the commonly used approximation |$\tilde{j}_\star \approx k_n v_s r_\mathrm{eff}$|⁠ , which depends on global unresolved quantities. In our sample, both effects lead to steeper slopes of |$\beta =0.48\pm 0.21$| and |$0.61\pm 0.21$|⁠ , respectively. To understand the shallow slope, we discuss observational effects and systematic uncertainties and analyse the retention of |$j_\star$| relative to the angular momentum of the halo |$j_h$| (angular momentum retention factor |$f_j =j_\star /j_h$|⁠). For the |$M_\star$| range covered by the sample |$9.5 \lt \log _{10} (M_\star /\mathrm{ M}_\odot) \lt 11.5$| (halo mass |$11.5 \lt \log _{10} (M_h/\mathrm{ M}_\odot) \lt 14$|⁠), we find large |$f_j$| values (⁠|$\gt 1$| in some cases) in low-mass haloes that decrease with increasing mass, suggesting a significant role of efficient angular momentum transport in these gas-rich systems, aided by the removal of low- |$j_\star$| gas via feedback-driven outflows in low-mass galaxies. [ABSTRACT FROM AUTHOR]

We investigate the planetary migration of low-mass planets (⁠|$M_p\in [1,15]\, \mathrm{ M}_{\oplus }$|⁠ , here |$\mathrm{ M}_{\oplus }$| is the Earth mass) in a gaseous disc containing a previously formed gap. We perform high-resolution 3D simulations with the fargo3d code. To create the gap in the surface density of the disc, we use a radial viscosity profile with a bump, which is maintained during the entire simulation time. We find that when the gap is sufficiently deep, the spiral waves excited by the planet trigger the Rossby wave instability, forming cyclonic (underdense) vortices at the edges of the gap. When the planet approaches the gap, it interacts with the vortices, which produce a complex flow structure around the planet. Remarkably, we find a widening of the horseshoe region of the planet produced by the vortex at the outer edge of the gap, which depending on the mass of the planet differs by at least a factor of two with respect to the standard horseshoe width. This inevitably leads to an increase in the co-rotation torque on the planet and produces an efficient trap to halt its inward migration. In some cases, the planet becomes locked in co-rotation with the outer vortex. Under this scenario, our results could explain why low-mass planets do not fall towards the central star within the lifetime of the protoplanetary disc. Lastly, the development of these vortices produces an asymmetric temporal evolution of the gap, which could explain the structures observed in some protoplanetary discs. [ABSTRACT FROM AUTHOR]

By means of three-dimensional resistive-magnetohydrodynamical models, we study the evolution of the so-called dead zones focused on the magnitude of the Reynolds and Maxwell stresses. We consider two different types of static resistivity radial profiles that give rise to an intermediate dead zone or an intermediate active zone. As we are interested in analysing the strength of angular momentum transport in these intermediate regions of the disc, we use as free parameters the radial extent of the intermediate dead (Δ r idz) or active (Δ r iact) zones, and the widths of the inner (⁠|$H_{b_1}$|⁠) and outer (⁠|$H_{b_2}$|⁠) transitions. We find that regardless of the width or radial extent of the intermediate zones, Rossby wave instability (RWI) develops at these transition boundaries, leading to the emergence of vortices and spiral waves. In the case of an intermediate dead zone when |$H_{b_1}\,H_{b_2}\le 0.8$|⁠ , the vortices are almost completely confined to the dead zone. Remarkably, we find that the formation of vortices at the inner transition can drag magnetic field lines into the dead zone stirring up the region that the vortex covers (reaching an α ≈ 10−2 value similar to that of an active zone). Vortices formed in the outer transition only modify the Reynolds stress tensor. Our results can be important to understanding angular momentum transport in poorly ionized regions within the disc due to magnetized vortices within dead zones. [ABSTRACT FROM AUTHOR]

Planets can carve gaps in the surface density of protoplanetary discs. The formation of these gaps can reduce the corotation torques acting on the planets. In addition, gaps can halt the accretion of solids on to the planets as dust and pebbles can be trapped at the edge of the gap. This accumulation of dust could explain the origin of the ring-like dust structures observed using high-resolution interferometry. In this work, we provide an empirical scaling relation for the depth of the gap cleared by a planet on an eccentric orbit as a function of the planet-to-star mass ratio q , the disc aspect ratio h , Shakura–Sunyaev viscosity parameter α, and planetary eccentricity e. We construct the scaling relation using a heuristic approach: we calibrate a toy model based on the impulse approximation with 2D hydrodynamical simulations. The scaling reproduces the gap depth for moderate eccentricities (e ≤ 4 h) and when the surface density contrast outside and inside the gap is ≤102. Our framework can be used as the basis of more sophisticated models aiming to predict the radial gap profile for eccentric planets. [ABSTRACT FROM AUTHOR]

Cosmological constraints from current and upcoming galaxy cluster surveys are limited by the accuracy of cluster mass calibration. In particular, optically identified galaxy clusters are prone to selection effects that can bias the weak lensing mass calibration. We investigate the selection bias of the stacked cluster lensing signal associated with optically selected clusters, using clusters identified by the redMaPPer algorithm in the Buzzard simulations as a case study. We find that at a given cluster halo mass, the residuals of redMaPPer richness and weak lensing signal are positively correlated. As a result, for a given richness selection, the stacked lensing signal is biased high compared with what we would expect from the underlying halo mass probability distribution. The cluster lensing selection bias can thus lead to overestimated mean cluster mass and biased cosmology results. We show that the lensing selection bias exhibits a strong scale dependence and is approximately 20–60 per cent for ΔΣ at large scales. This selection bias largely originates from spurious member galaxies within ±20–60  |$h^{-1}\, \rm Mpc$| along the line of sight, highlighting the importance of quantifying projection effects associated with the broad redshift distribution of member galaxies in photometric cluster surveys. While our results qualitatively agree with those in the literature, accurate quantitative modelling of the selection bias is needed to achieve the goals of cluster lensing cosmology and will require synthetic catalogues covering a wide range of galaxy–halo connection models. [ABSTRACT FROM AUTHOR]

We present detailed stellar specific angular momentum (j *) measurements of 10 star-forming galaxies at z ∼ 1.5−2, using both high and low spatial resolution integral field spectroscopic data. We developed a code that simultaneously models the adaptive optics (AO) assisted observations from OSIRIS/SINFONI along with their natural seeing (NS) counterparts from KMOS at spatial resolutions of [0.1−0.4] arcsec and [0.6−1.0] arcsec, respectively. The AO data reveal 2/10 systems to be mergers and for the remaining eight the mean uncertainties |$\bar{\Delta }j_*$| decrease from 49 per cent (NS), and 26.5 per cent (AO), to 16 per cent in the combined analysis. These j * measurements agree within 20 per cent with simple estimates (⁠|$\tilde{j_*}$|⁠) calculated from Hubble Space Telescope photometry and NS kinematics; however, higher resolution kinematics are required to first identify these discs. We find that the choice of surface mass density model and the measurement of effective radius from photometry are the key sources of systematic effects in the measurement of j * between different analyses. Fitting the j * versus M * relations (Fall 1983) with a fixed power-law slope of β = 2/3, we find a zero-point consistent with prior NS results at z ≥ 1 within ∼0.3 dex. Finally, we find a ∼0.38 dex scatter about that relation that remains high despite the AO data so we conclude it is intrinsic to galaxies at z > 1. This compares to a scatter of ≤0.2 dex for discs at z ≃ 0 pointing to a settling of the Fall relation with cosmic time. [ABSTRACT FROM AUTHOR]

We describe our non-linear emulation (i.e. interpolation) framework that combines the halo occupation distribution (HOD) galaxy bias model with N -body simulations of non-linear structure formation, designed to accurately predict the projected clustering and galaxy–galaxy lensing signals from luminous red galaxies in the redshift range 0.16 < z < 0.36 on comoving scales 0.6 < r p < 30 |$h^{-1} \, \text{Mpc}$|⁠. The interpolation accuracy is ≲ 1–2 per cent across the entire physically plausible range of parameters for all scales considered. We correctly recover the true value of the cosmological parameter S 8 = (σ8/0.8228)(Ωm/0.3107)0.6 from mock measurements produced via subhalo abundance matching (SHAM)-based light-cones designed to approximately match the properties of the SDSS LOWZ galaxy sample. Applying our model to Baryon Oscillation Spectroscopic Survey (BOSS) Data Release 14 (DR14) LOWZ galaxy clustering and galaxy-shear cross-correlation measurements made with Sloan Digital Sky Survey (SDSS) Data Release 8 (DR8) imaging, we perform a prototype cosmological analysis marginalizing over w CDM cosmological parameters and galaxy HOD parameters. We obtain a 4.4 per cent measurement of S 8 = 0.847 ± 0.037, in 3.5σ tension with the Planck cosmological results of 1.00 ± 0.02. We discuss the possibility of underestimated systematic uncertainties or astrophysical effects that could explain this discrepancy. [ABSTRACT FROM AUTHOR]

Cluster weak lensing is a sensitive probe of cosmology, particularly the amplitude of matter clustering σ8 and matter density parameter Ωm. The main nuisance parameter in a cluster weak lensing cosmological analysis is the scatter between the true halo mass and the relevant cluster observable, denoted |$\sigma _{\ln M_\mathrm{ c}}$|⁠. We show that combining the cluster weak lensing observable ΔΣ with the projected cluster–galaxy cross-correlation function w p,cg and galaxy autocorrelation function w p,gg can break the degeneracy between σ8 and |$\sigma _{\ln M_\mathrm{ c}}$| to achieve tight, per cent-level constraints on σ8. Using a grid of cosmological N -body simulations, we compute derivatives of ΔΣ, w p,cg, and w p,gg with respect to σ8, Ωm, |$\sigma _{\ln M_\mathrm{ c}}$|⁠ , and halo occupation distribution (HOD) parameters describing the galaxy population. We also compute covariance matrices motivated by the properties of the Dark Energy Survey cluster and weak lensing survey and the BOSS CMASS galaxy redshift survey. For our fiducial scenario combining ΔΣ, w p,cg, and w p,gg measured over 0.3−30.0  h −1 Mpc, for clusters at z  = 0.35−0.55 above a mass threshold M c ≈ 2 × 1014  h −1 M⊙, we forecast a |$1.4{{\ \rm per\ cent}}$| constraint on σ8 while marginalizing over |$\sigma _{\ln M_\mathrm{ c}}$| and all HOD parameters. Reducing the mass threshold to 1 × 1014  h −1 M⊙ and adding a z  = 0.15−0.35 redshift bin sharpens this constraint to |$0.8{{\ \rm per\ cent}}$|⁠. The small-scale (r p < 3.0  h −1 Mpc) 'mass function' and large-scale (r p > 3.0  h −1 Mpc) 'halo-mass cross-correlation' regimes of ΔΣ have comparable constraining power, allowing internal consistency tests from such an analysis. [ABSTRACT FROM AUTHOR]

The combination of galaxy–galaxy lensing (GGL) with galaxy clustering is one of the most promising routes to determining the amplitude of matter clustering at low redshifts. We show that extending clustering+GGL analyses from the linear regime down to |${\sim } 0.5 \, h^{-1}$| Mpc scales increases their constraining power considerably, even after marginalizing over a flexible model of non-linear galaxy bias. Using a grid of cosmological N -body simulations, we construct a Taylor-expansion emulator that predicts the galaxy autocorrelation ξgg(r) and galaxy-matter cross-correlation ξgm(r) as a function of σ8, Ωm, and halo occupation distribution (HOD) parameters, which are allowed to vary with large-scale environment to represent possible effects of galaxy assembly bias. We present forecasts for a fiducial case that corresponds to BOSS LOWZ galaxy clustering and SDSS-depth weak lensing (effective source density ∼0.3 arcmin−2). Using tangential shear and projected correlation function measurements over |$0.5 \le r_\mathrm{ p} \le 30 \, h^{-1}$| Mpc yields a 2 per cent constraint on the parameter combination |$\sigma _8\Omega _\mathrm{ m}^{0.6}$|⁠, a factor of two better than a constraint that excludes non-linear scales (⁠|$r_\mathrm{ p} \gt 2 \, h^{-1}$| Mpc, |$4 \, h^{-1}$| Mpc for γt, |$w$| p). Much of this improvement comes from the non-linear clustering information, which breaks degeneracies among HOD parameters. Increasing the effective source density to 3 arcmin−2 sharpens the constraint on |$\sigma _8\Omega _\mathrm{ m}^{0.6}$| by a further factor of two. With robust modelling into the non-linear regime, low-redshift measurements of matter clustering at the 1-per cent level with clustering+GGL alone are well within reach of current data sets such as those provided by the Dark Energy Survey. [ABSTRACT FROM AUTHOR]