bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Azulejo as Colonial Symbol of Power: a Deconstruction through Sugar and Art
Authors: Miller Shelley 
Published: November 2020

I create murals that look like azulejos, depicting caravels and many decorative features seen in traditional azulejos, but my murals are made entirely of sugar. I make the sugar tiles and hand paint them with edible inks.
I am interested in the azulejo, specifically with imagery of ships, as a symbol of colonial power and of national pride (the Nation of Portugal), but only for the means to subvert this pride. I developed this work in Brazil, addressing the country’s history of colonization and the slave trade that supported Portugal’s sugar empire.
I continue to use the blue tile reference, even outside the context of Brazil, because I want to reference the general construct of colonization and slavery, showing how oppression has found new forms. I install my ephemeral murals on city walls, where they wash away, fade, crumble and decay, animating a more realistic version of history.
Architectures of Exoplanetary Systems. III. Eccentricity and Mutual Inclination Distributions of AMD-stable Planetary Systems
Authors: He Matthias Y. , Ford Eric B. , Ragozzine Darin , Carrera Daniel 
Published: November 2020

AbstractThe angular momentum deficit (AMD) of a planetary system is a measure of its orbital excitation and a predictor of long-term stability. We adopt the AMD-stability criterion to constrain the orbital architectures for exoplanetary systems. Previously, He et al. showed through forward modeling (SysSim) that the observed multiplicity distribution can be well reproduced by two populations consisting of a low and a high mutual inclination component. Here, we show that a broad distribution of mutual inclinations arising from systems at the AMD-stability limit can also match the observed Kepler population. We show that distributing a planetary system’s maximum AMD among its planets results in a multiplicity-dependent distribution of eccentricities and mutual inclinations. Systems with intrinsically more planets have lower median eccentricities and mutual inclinations, and this trend is well described by power-law functions of the intrinsic planet multiplicity (n):and, whereandare the medians of the eccentricity and inclination distributions. We also find that intrinsic single planets have higher eccentricities (σe,1 ∼ 0.25) than multiplanet systems and that the trends with multiplicity appear in the observed distributions of period-normalized transit duration ratios. We show that the observed preferences for planet-size orderings and uniform spacings are more extreme than what can be produced by the detection biases of the Kepler mission alone. Finally, we find that for systems with detected transiting planets between 5 and 10 days, there is another planet with a greater radial velocity signal ≃53% of the time.
An Unusual Transmission Spectrum for the Sub-Saturn KELT-11b Suggestive of a Subsolar Water Abundance
Authors: Colón Knicole D. , Kreidberg Laura , Welbanks Luis , Line Michael R. , Madhusudhan Nikku , Beatty Thomas , Tamburo Patrick , Stevenson Kevin B. , Mandell Avi , Rodriguez Joseph E. , Barclay Thomas , Lopez Eric D. , Stassun Keivan G. , Angerhausen Daniel , Fortney Jonathan J. , James David J. , Pepper Joshua , Ahlers John P. , Plavchan Peter , Awiphan Supachai , Kotnik Cliff , McLeod Kim K. , Murawski Gabriel , Chotani Heena , LeBrun Danny , Matzko William , Rea David , Vidaurri Monica , Webster Scott , Williams James K. , Cox Leafia Sheraden , Tan Nicole , Gilbert Emily A. 
Published: November 2020

Abstract
We present an optical-to-infrared transmission spectrum of the inflated sub-Saturn KELT-11b measured with the Transiting Exoplanet Survey Satellite (TESS), the Hubble Space Telescope (HST) Wide Field Camera 3 G141 spectroscopic grism, and the Spitzer Space Telescope (Spitzer) at 3.6 μm, in addition to a Spitzer 4.5 μm secondary eclipse. The precise HST transmission spectrum notably reveals a low-amplitude water feature with an unusual shape. Based on free-retrieval analyses with varying molecular abundances, we find strong evidence for water absorption. Depending on model assumptions, we also find tentative evidence for other absorbers (HCN, TiO, and AlO). The retrieved water abundance is generally ≲0.1× solar (0.001–0.7× solar over a range of model assumptions), several orders of magnitude lower than expected from planet formation models based on the solar system metallicity trend. We also consider chemical-equilibrium and self-consistent 1D radiative-convective equilibrium model fits and find that they, too, prefer low metallicities ([M/H] ≲ −2, consistent with the free-retrieval results). However, all of the retrievals should be interpreted with some caution because they either require additional absorbers that are far out of chemical equilibrium to explain the shape of the spectrum or are simply poor fits to the data. Finally, we find that the Spitzer secondary eclipse is indicative of full heat redistribution from KELT-11b’s dayside to nightside, assuming a clear dayside. These potentially unusual results for KELT-11b’s composition are suggestive of new challenges on the horizon for atmosphere and formation models in the face of increasingly precise measurements of exoplanet spectra.
Endogenic and Exogenic Contributions to Visible-wavelength Spectra of Europa’s Trailing Hemisphere
Authors: Trumbo Samantha K. , Brown Michael E. , Hand Kevin P. 
Published: November 2020

Abstract
The composition of Europa’s trailing hemisphere reflects the combined influences of endogenous geologic resurfacing and exogenous sulfur radiolysis. Using spatially resolved visible-wavelength spectra of Europa obtained with the Hubble Space Telescope, we map multiple spectral features across the trailing hemisphere and compare their geographies with the distributions of large-scale geology, magnetospheric bombardment, and surface color. Based on such comparisons, we interpret some aspects of our spectra as indicative of purely exogenous sulfur radiolysis products and other aspects as indicative of radiolysis products formed from a mixture of endogenous material and magnetospheric sulfur. The spatial distributions of two of the absorptions seen in our spectra—a widespread downturn toward the near-UV and a distinct feature at 530 nm—appear consistent with sulfur allotropes previously suggested from ground-based spectrophotometry. However, the geographies of two additional features—an absorption feature at 360 nm and the spectral slope at red wavelengths—are more consistent with endogenous material that has been altered by sulfur radiolysis. We suggest irradiated sulfate salts as potential candidates for this material, but we are unable to identify particular species with the available data.
Early High-contrast Imaging Results with Keck/NIRC2-PWFS: The SR 21 Disk
Authors: Uyama Taichi , Ren 任 Bin 彬 , Mawet Dimitri , Ruane Garreth , Bond Charlotte Z. , Hashimoto Jun , Liu Michael C. , Muto Takayuki , Ruffio Jean-Baptiste , Wallack Nicole , Baranec Christoph , Bowler Brendan P. , Choquet Elodie , Chun Mark , Delorme Jacques-Robert , Fogarty Kevin , Guyon Olivier , Jensen-Clem Rebecca , Meshkat Tiffany , Ngo Henry , Wang Jason J. , Wang Ji , Wizinowich Peter , Ygouf Marie , Zuckerman Benjamin 
Published: November 2020

Abstract
High-contrast imaging of exoplanets and protoplanetary disks depends on wave front sensing and correction made by adaptive optics instruments. Classically, wave front sensing has been conducted at optical wavelengths, which made high-contrast imaging of red targets such as M-type stars or extincted T Tauri stars challenging. Keck/NIRC2 has combined near-infrared (NIR) detector technology with the pyramid wave front sensor (PWFS). With this new module we observed SR 21, a young star that is brighter at NIR wavelengths than at optical wavelengths. Compared with the archival data of SR 21 taken with the optical wave front sensing we achieved ∼20% better Strehl ratio in similar natural seeing conditions. Further post-processing utilizing angular differential imaging and reference-star differential imaging confirmed the spiral feature reported by the Very Large Telescope/Spectro-Polarimetric High-contrast Exoplanet REsearch instrument polarimetric observation, which is the first detection of the SR 21 spiral in total intensity at L′ band. We also compared the contrast limit of our result (10−4 at 04 and 2 × 10−5 at 10) with the archival data that were taken with optical wave front sensing and confirmed the improvement, particularly at ≤05. Our observation demonstrates that the NIR PWFS improves AO performance and will provide more opportunities for red targets in the future.
Characterizing the Evolved Stellar Population in the Galactic Foreground. I. Bolometric Magnitudes, Spatial Distribution and Period–Luminosity Relations
Authors: Quiroga-Nuñez Luis Henry , van Langevelde Huib Jan , Sjouwerman Loránt O. , Pihlström Ylva M. , Brown Anthony G. A. , Rich R. Michael , Stroh Michael C. , Lewis Megan O. , Habing Harm J. 
Published: November 2020

Abstract
Radio campaigns using maser stellar beacons have provided crucial information to characterize Galactic stellar populations. Currently, the Bulge Asymmetries and Dynamical Evolution (BAaDE) project is surveying infrared (IR) color-selected targets for SiO masers. This provides a sample of evolved stars that can be used to study the inner, optically obscured Galaxy using line-of-sight velocities and possibly very long baseline interferometry proper motions. In order to use the BAaDE sample for kinematic studies, the stellar population should be characterized. In this study, the BAaDE targets have been cross-matched with IR (2MASS) and optical (Gaia) samples. By exploring the synergies of this cross-match together with Gaia parallaxes and extinction maps, the local (d < 2 kpc) asymptotic giant branch (AGB) stars can be characterized. We have defined a BAaDE–Gaia sample of 20,111 sources resulting from cross-matching BAaDE targets with IR and optical surveys. From this sample, a local sample of 1812 evolved stars with accurate parallax measurements, confirmed evolved stellar evolution stage, and within 2 kpc distance around the Sun was selected, for which absolute (bolometric) magnitudes are estimated. The evolved stellar population with Gaia counterparts that are variable seems to be predominantly associated with AGB stars with moderate luminosity (

) and periods between 250 and 1250 days.
A Significant Excess in Major Merger Rate for AGNs with the Highest Eddington Ratios at z < 0.2
Authors: Marian Victor , Jahnke Knud , Andika Irham , Bañados Eduardo , Bennert Vardha N. , Cohen Seth , Husemann Bernd , Kaasinen Melanie , Koekemoer Anton M. , Mechtley Mira , Onoue Masafusa , Schindler Jan-Torge , Schramm Malte , Schulze Andreas , Silverman John D. , Smirnova-Pinchukova Irina , Wel Arjen van der , Villforth Carolin , Windhorst Rogier A. 
Published: November 2020

Abstract
Observational studies are increasingly finding evidence against major mergers being the dominant mechanism responsible for triggering an active galactic nucleus (AGN). After studying the connection between major mergers and AGNs with the highest Eddington ratios at z = 2, we here expand our analysis to

, exploring the same AGN parameter space. Using ESO VLT/FORS2

,

, and color images, we examine the morphologies of 17 galaxies hosting AGNs with Eddington ratios

, and 25 mass- and redshift-matched control galaxies. To match the appearance of the two samples, we add synthetic point sources to the inactive comparison galaxies. The combined sample of AGN and inactive galaxies was independently ranked by 19 experts with respect to the degree of morphological distortion. We combine the resulting individual rankings into multiple overall rankings, from which we derive the respective major merger fractions of the two samples. With a best estimate of f
m,agn = 0.41 ± 0.12 for the AGN host galaxies and f
m,ina = 0.08 ± 0.06 for the inactive galaxies, our results imply that our AGN host galaxies have a significantly higher merger rate, regardless of the observed wavelength or applied methodology. We conclude that although major mergers are an essential mechanism to trigger local high Eddington ratio AGNs at

, the origin of

of this specific AGN subpopulation still remains unclear.
Constraining the Chemical Signatures and the Outburst Mechanism of the Class 0 Protostar HOPS 383
Authors: Sharma Rajeeb , Tobin John J. , Sheehan Patrick D. , Megeath S. Thomas , Fischer William J. , Jørgensen Jes K. , Safron Emily J. , Nagy Zsofia 
Published: November 2020

Abstract
We present observations toward HOPS 383, the first known outbursting Class 0 protostar located within the Orion molecular cloud using the Atacama Large Millimeter/submillimeter Array (ALMA), Very Large Array (VLA), and Submillimeter Array (SMA). The SMA observations reveal envelope scale continuum and molecular line emission surrounding HOPS 383 at 0.85, 1.1, and 1.3 mm. The images show that HCO+ and H13CO+ peaks on or near the continuum, while N2H+ is reduced at the same position. This reflects the underlying chemistry where CO evaporating close to the protostar destroys N2H+ while forming HCO+. We also observe the molecular outflow traced by 12CO (

) and (

). A disk is resolved in the ALMA 0.87 mm dust continuum, orthogonal to the outflow direction, with an apparent radius of ∼62 au. Radiative transfer modeling of the continuum gives disk masses of 0.02 M
⊙ when fit to the ALMA visibilities. The models including VLA 8 mm data indicate that the disk mass could be up to a factor of 10 larger due to lower dust opacity at longer wavelengths. The disk temperature and surface density profiles from the modeling, and an assumed protostar mass of 0.5 M
⊙ suggest that the Toomre Q parameter < 1 before the outburst, making gravitational instability a viable mechanism to explain outbursts at an early age if the disk is sufficiently massive.
A Photoionized Accretion Disk around a Young High-mass Star
Authors: Guzmán Andrés E. , Sanhueza Patricio , Zapata Luis , Garay Guido , Rodríguez Luis Felipe 
Published: November 2020

Abstract
We present high spatial resolution (52 au) observations of the high-mass young stellar object (HMYSO) G345.4938+01.4677 made using the Atacama Large Millimeter/submillimeter Array. This O-type HMYSO is located at 2.38 kpc and is associated with a luminosity of 1.5 × 105
L
☉. We detect circumstellar emission from the H38β hydrogen recombination line showing a compact structure rotating perpendicularly to the previously detected radio jet. We interpret this emission as tracing a photoionized accretion disk around the HMYSO. While this disk-like structure seems currently too small to sustain continued accretion, the data present direct observational evidence of how disks can effectively survive the photoionization feedback from young high-mass stars. We also report the detection of a low-mass young stellar object in the vicinity of the HMYSO and suggest that it forms a high-mass and low-mass star binary system.
Morphological and Rotation Structures of Circumgalactic Mg ii Gas in the EAGLE Simulation and the Dependence on Galaxy Properties
Authors: Ho Stephanie H. , Martin Crystal L. , Schaye Joop 
Published: November 2020

Abstract
Low-ionization-state Mg ii gas has been extensively studied in quasar sightline observations to understand the cool, ∼104 K gas in the circumgalactic medium. Motivated by recent observations showing that the Mg ii gas around low-redshift galaxies has significant angular momentum, we use the high-resolution EAGLE cosmological simulation to analyze the morphological and rotation structures of the z ≈ 0.3 circumgalactic Mg ii gas and examine how they change with the host galaxy properties. Around star-forming galaxies, we find that the Mg ii gas has an axisymmetric instead of a spherical distribution, and the axis of symmetry aligns with that of the Mg ii gas rotation. A similar rotating structure is less commonly found in the small sample of simulated quiescent galaxies. We also examine how often Mg ii gas around galaxies selected using a line-of-sight velocity cut includes gas physically outside of the virial radius (r
vir). For example, we show that at an impact parameter of 100 pkpc, a ±500 km s−1 velocity cut around galaxies with stellar masses of 109–109.5
M
⊙ (1010–1010.5
M
⊙) selects Mg ii gas beyond the virial radius 80% (6%) of the time. Because observers typically select Mg ii gas around target galaxies using such a velocity cut, we discuss how this issue affects the study of circumgalactic Mg ii gas properties, including the detection of corotation. While the corotating Mg ii gas generally extends beyond 0.5r
vir, the Mg ii gas outside of the virial radius contaminates the corotation signal and makes observers less likely to conclude that gas at large impact parameters (e.g., ≳0.25r
vir) is corotating.
Structure and Rotation of Young Massive Star Clusters in a Simulated Dwarf Starburst
Authors: Lahén Natalia , Naab Thorsten , Johansson Peter H. , Elmegreen Bruce , Hu Chia-Yu , Walch Stefanie 
Published: November 2020

Abstract
We analyze the three-dimensional shapes and kinematics of the young star cluster population forming in a high-resolution griffin project simulation of a metal-poor dwarf galaxy starburst. The star clusters, which follow a power-law mass distribution, form from the cold phase interstellar medium with an initial mass function sampled with individual stars down to four solar masses at sub-parsec spatial resolution. Massive stars and their important feedback mechanisms are modeled in detail. The simulated clusters follow a surprisingly tight relation between the specific angular momentum and mass with indications of two sub-populations. Massive clusters (M
cl ≳ 3 × 104
M
⊙) have the highest specific angular momenta at low ellipticities (ϵ ∼ 0.2) and show alignment between their shapes and rotation. Lower mass clusters have lower specific angular momenta with larger scatter, show a broader range of elongations, and are typically misaligned indicating that they are not shaped by rotation. The most massive clusters (M ≳ 105
M
⊙) accrete gas and protoclusters from a ≲100 pc scale local galactic environment on a t ≲ 10 Myr timescale, inheriting the ambient angular momentum properties. Their two-dimensional kinematic maps show ordered rotation at formation, up to v ∼ 8.5 km s−1, consistent with observed young massive clusters and old globular clusters, which they might evolve into. The massive clusters have angular momentum parameters λ
R ≲ 0.5 and show Gauss–Hermite coefficients h
3 that are anti-correlated with the velocity, indicating asymmetric line-of-sight velocity distributions as a signature of a dissipative formation process.
Clustering of LRGs in the DECaLS DR8 Footprint: Distance Constraints from Baryon Acoustic Oscillations Using Photometric Redshifts
Authors: Sridhar Srivatsan , Song Yong-Seon , Ross Ashley J. , Zhou Rongpu , Newman Jeffrey A. , Chuang Chia-HSun , Blum Robert , Gaztañaga Enrique , Landriau Martin , Prada Francisco 
Published: November 2020

Abstract
A photometric redshift sample of luminous red galaxies (LRGs) obtained from the DECam Legacy Survey (DECaLS) is analyzed to probe cosmic distances by exploiting the wedge approach of the two-point correlation function. Although the cosmological information is highly contaminated by the uncertainties existing in the photometric redshifts from the galaxy map, an angular diameter distance can be probed at the perpendicular configuration in which the measured correlation function is minimally contaminated. An ensemble of wedged correlation functions selected up to a given threshold based on having the least contamination was studied in previous work (Sridhar & Song 2019) using simulations, and the extracted cosmological information was unbiased within this threshold. We apply the same methodology for analyzing the LRG sample from DECaLS, which will provide the optical imaging for targeting two-thirds of the Dark Energy Spectroscopic Instrument footprint and measure the angular diameter distances at z = 0.69 and z = 0.87 to be

and

with a fractional error of 4.77% and 6.09%, respectively. We obtain a value of H
0 = 66.58 ± 5.31 km s−1 Mpc−1, which supports the H
0 measured by all other baryon acoustic oscillation results and is consistent with the ΛCDM model.
Tidal Disruptions of Main-sequence Stars. V. The Varieties of Disruptions
Authors: Krolik Julian , Piran Tsvi , Ryu Taeho 
Published: November 2020

Abstract
Tidal disruption events (TDEs) are generally imagined as the complete disruption of a star when it passes close to a supermassive black hole (SMBH). Relativistic apsidal precession is thought to quickly “circularize” the bound debris, forming a compact accretion disk, which then emits a flare of standardized light curve and spectrum. We show here that this picture holds in only a minority of cases. TDEs are more diverse and can be grouped into several categories distinguished by stellar pericenter distance r

p
; we estimate the relative frequency of these categories. Rapid circularization is rare both because it requires

(

) and because most events with

lead to direct capture. For larger pericenter distances,

(for M
BH = 106
M
⊙), main-sequence stars with M
* ≲ 3 are completely disrupted, but the bound debris orbits are highly eccentric and possess semimajor axes ∼100× the scale of the expected compact disk. Partial disruptions with fractional mass loss ≳10% occur with a rate similar to that of total disruptions; for fractional mass loss ≳50%, the rate is ≈1/3 as large. Partial disruptions—which must precede total disruptions when the stars’ angular momenta evolve in the “empty loss-cone” regime—change the orbital energy by factors ≳O(1). Partial disruption remnants are in general far from thermal equilibrium. Depending on its orbital energy and conditions within the stellar cluster surrounding the SMBH, a remnant may return after ∼O(100)–O(1000) yr and be fully disrupted, or it may rejoin the stellar cluster.