A new, much-improved model of the Galactic magnetic field (GMF) is presented. We use theWMAP7 Galactic synchrotron emission map and more than 40,000 extragalactic rotation measures to constrain the parameters of the GMF model, which is substantially generalized compared with earlier work to now include an out-of-plane component (as suggested by observations of external galaxies) and striated-random fields (motivated by theoretical considerations). The new model provides a greatly improved fit to observations. Consistent with our earlier analyses, the best-fit model has a disk field and an extended halo field. Our new analysis reveals the presence of a large, out-of-plane component of the GMF; as a result, the polarized synchrotron emission of our Galaxy seen by an edge-on observer is predicted to look intriguingly similar to what has been observed in external edge-on galaxies. We find evidence that the cosmic-ray electron density is significantly larger than given by GALPROP or else that there is a widespread striated component to the GMF.

We present revised near-infrared albedo fits of 2835 main-belt asteroids observed byWISE/NEOWISE over the course of its fully cryogenic survey in 2010. These fits are derived from reflected-light near-infrared images taken simultaneously with thermal emission measurements, allowing for more accurate measurements of the near-infrared albedos than is possible for visible albedo measurements. Because our sample requires reflected light measurements, it undersamples small, low-albedo asteroids, as well as those with blue spectral slopes across the wavelengths investigated. We find that the main belt separates into three distinct groups of 6%, 16%, and 40% reflectance at 3.4 μm. Conversely, the 4.6 μm albedo distribution spans the full range of possible values with no clear grouping. Asteroid families show a narrow distribution of 3.4 μm albedos within each family that map to one of the three observed groupings, with the (221) Eos family being the sole family associated with the 16% reflectance 3.4 μm albedo group. We show that near-infrared albedos derived from simultaneous thermal emission and reflected light measurements are important indicators of asteroid taxonomy and can identify interesting targets for spectroscopic follow-up.

We report the results of one of the most sensitive pulsar surveys to date targeting the innermost region of the Galactic center (GC) using the Robert C. Byrd Green Bank Telescope atX band (8–12 GHz) using data from the Breakthrough Listen initiative. In total, we collected 9.5 hr of data covering the widerdiameter of the GC bulge, and 11 hr on the inner 14 region between 2021 May and 2023 December. We conducted a comprehensive Fourier-domain periodicity search targeting both canonical pulsars (CPs) and millisecond pulsars (MSPs), using constant and linearly changing acceleration searches to improve sensitivity to compact binaries. Assuming weak scattering, our searches reached luminosity limits of for CPs and for MSPs—sensitive enough to detect the most luminous pulsars expected in the GC. Among 5282 signal candidates, we identify an interesting 8.19 ms MSP candidate (dispersion measure (DM) of 2775 pc cm⁻³), persistent in time and frequency across a 1 hr scan at a flux density of. We introduce a novel randomization test for evaluating candidate significance against noise fluctuations, including signal persistence via Kolmogorov–Smirnov tests and flux-versus-DM behavior. We are unable to make a definitive claim about the candidate due to a mixed degree of confidence from these tests and, more broadly, its nondetection in subsequent observations. This deepens the ongoing missing pulsar problem in the GC, reinforcing the idea that strong scattering and/or extreme orbital dynamics may obscure pulsar signals in this region.

Carbonaceous cosmic dust is formed in the circumstellar envelopes of asymptotic giant branch stars and supernovae ejecta. Reprocessed carbonaceous cosmic dust, abundant in the light elements C, H, O, and N is found in asteroids and comets. These elements form dust that is well described as an amorphous, covalently bonded network solid with a structure that is expected to reflect the key formative influences of ion bombardment, temperature modification, and UV irradiation. Ion bombardment of a dust grain by an energetic particle in a stellar wind creates a nonequilibrium thermal spike event, which contrasts with the close-to-equilibrium process of annealing under the local ambient conditions. There is a gap in our knowledge of how to distinguish ion bombardment as a synthesis process from postsynthesis thermal modification through infrared spectroscopy. Here we synthesize dust from molecular precursors under a range of controlled space-like conditions to form a database of IR spectra. We apply principal component analysis to show that the first principal component correlates with ion bombardment intensity during synthesis and the second principal component correlates with annealing temperature. The spectral loading curves of these two principal components are proposed as potential diagnostic tools to uncover past formative influences on cosmic dust as well as on the carbonaceous content of asteroids such as Bennu and Ryugu. Amorphous organic networks composed of the CHON elements unify previous ideas on cosmic dust by encompassing features of PAHs, tholins, and mixed aliphatic–aromatic nanoparticles.

The Habitable Zone (HZ) is defined by the possibility of sustaining liquid water on a planetary surface. In the solar system, the HZ for a conservative climate model extends approximately between the orbits of Earth and Mars. We elaborate on earlier HZ models and apply an analytical climate model of the temperature distribution on tidally locked planets to extend the HZ. We show that planets orbiting M- and K-dwarf stars may maintain liquid water on their night side, significantly closer to their host star than the inner border of the conservative HZ. We calculate the extended borders of the HZ in the flux–effective temperature diagram. This extension may explain the presence of water vapor and other volatile gases in the transmission spectra of warm Super-Earth-sized exoplanets closely orbiting M dwarfs, recently detected by JWST. We also mention the HZ extension outward, due to subglacial liquid water in the form of intraglacial lakes or subglacial melting.

We report the multiwavelength properties of eROSITA Final Equatorial Depth Survey (eFEDS) J084222.9+001000 (hereafter ID830), a quasar atz = 3.4351, identified as the most X-ray luminous radio-loud quasar in the eFEDS field. ID830 shows a rest-frame 0.5–2 keV luminosity of, with a steep X-ray photon index (Γ = 2.43 ± 0.21), and a significant radio counterpart detected with the Very Large Array FIRST 1.4 GHz and Very Large Array Sky Survey 3 GHz bands. The rest-frame UV to optical spectra from Sloan Digital Sky Survey and Subaru/MOIRCSJ band show a dust-reddened quasar feature withA_V = 0.39 ± 0.08 mag, and the expected bolometric active galactic nuclei luminosity from the dust-extinction-corrected UV luminosity reachesL_bol,3000Å = (7.62 ± 0.31) × 10⁴⁶ erg s⁻¹. We estimate a black hole mass ofM_BH = (4.40 ± 0.72) × 10⁸ M_⊙ based on the MgIIλ2800 emission-line width, and Eddington ratios from the dust-extinction-corrected UV continuum luminosity and X-ray luminosity that reachλ_Edd,UV = 1.44 ± 0.24 andλ_Edd,X = 12.8 ± 3.9, respectively, both indicating super-Eddington accretion. ID830 shows a high ratio of UV to X-ray luminosities,α_OX = −1.20 ± 0.07 (orα_OX = −1.42 ± 0.07 after correcting for jet-linked X-ray excess), higher than quasars and little red dots in the super-Eddington phase with similar UV luminosities, withα_OX < −1.8. Such a highα_OX suggests the coexistence of a prominent radio jet and X-ray corona in this high-Eddington-accretion phase. We propose that ID830 may be in a transitional phase after an accretion burst, evolving from a super-Eddington to a sub-Eddington state, which could naturally describe the highα_OX.

The Galilean moons exhibit a decrease in bulk density with distance from Jupiter, which may reflect differences in evolutionary paths and water loss. Early in its history, Jupiter was more luminous, which may have driven substantial atmospheric escape on Io and Europa. We investigate whether Io could have lost its water inventory while Europa retained its volatiles, assuming both moons initially accreted hydrous silicates. The formation and early thermal evolution of the protosatellites are modeled using an interior evolution model coupled with an atmospheric escape framework. Dehydration timescales and volatile losses for Io and Europa are computed during their early evolution, accounting for accretional heating from both satellitesimal and pebble accretion and irradiation from Jupiter’s primordial luminosity. Europa likely retained most of its volatiles under nearly all plausible formation and evolution scenarios, as large-scale dehydration would have taken place only after the first ∼10 Myr of its evolution. In contrast, Io was unlikely to lose a substantial amount of water through atmospheric escape and therefore probably accreted predominantly anhydrous silicates. If Europa initially accreted hydrous minerals, the present-day volatile contrast between Io and Europa could be explained by their relative locations with respect to the phyllosilicate dehydration line in the Jovian subnebula. Distinct evolutionary pathways or atmospheric escape processes alone appear insufficient to reproduce the observed differences.

We present ongoing radio observations of the tidal disruption event (TDE) AT2018hyz, which was first detected in the radio at 972 days after disruption, following multiple nondetections from earlier searches. The new observations presented here span ≈1370–2160 days and 0.88–240 GHz. We find that the light curves continue to rise at all frequencies during this time period, following a power law of aboutF_ν ∝ t³ (compared toF_ν ∝ t^5.7 at 972–1400 days) and reaching a peak luminosity ofL ≈ 10⁴⁰ erg s⁻¹, comparable to the luminosity of the relativistic TDE Sw 1644+57 on the same timescale. The multifrequency data indicate that the peak frequency does not significantly evolve over the 1030 days span of our observations, while the peak flux density increases by an order of magnitude. The observed behavior is consistent with two possible scenarios: (i) a delayed spherical outflow launched about 620 days postdisruption with a velocity of ≈0.3c and an energy of ∼10⁵⁰ erg; or (ii) a highly off-axis (≈80°–90°) relativistic jet with a Lorentz factor of Γ ∼ 8 andE_K ≈ 10⁵² erg. Continued radio observations to capture the light-curve peak, as well as very long baseline interferometry observations, could distinguish between these scenarios.

Analytical models are essential for building physical intuition and guiding the interpretation of exoplanet observations by clarifying the dependencies that shape atmospheric signatures. I present a generalization of the classical isothermal, isobaric transmission model by allowing the opacity to vary with pressure as a power law,κ ∝ Pⁿ, and explicitly defining the reference opacityκ₀ at a chosen pressureP₀. By treating the slant optical depth as an Abel transform of the radial absorption coefficient, I derive a closed-form expression for the effective transit radius in a hydrostatic, isothermal atmosphere with pressure-dependent opacity. The solution provides a compact framework for exploring nonisobaric effects and explicitly links the vertical opacity gradient to observable spectral features. I benchmark the model against empirical transmission spectra of Earth and the hot Jupiter WASP-39b, finding a significantly improved fit relative to the isobaric formula. This generalized expression offers a physically interpretable foundation for analyzing high-precision spectra from JWST and upcoming ARIEL observations, and can serve as a basis for semianalytical retrieval approaches optimized for computational efficiency.

We introduce a simulation-based inference framework to constrain the origins of individual ultra-high-energy cosmic rays by combining realistic three-dimensional propagation modeling with Bayesian parameter estimation. Our method integratesCRPropa 3 simulations, including all relevant interactions and magnetic deflections in both Galactic and extragalactic fields, with approximate Bayesian computation to infer posterior distributions over key parameters such as source position, distance, energy, and magnetic field properties. This approach allows joint constraints from the observed energy and arrival direction to be applied simultaneously, naturally incorporating their correlations in addition to relevant modelling uncertainties. We demonstrate our method by applying it to the Amaterasu particle detected by the TA observatory, the second-highest-energy cosmic ray ever detected. The resulting posterior distributions quantify the regions of space consistent with its reconstructed properties under different energy and composition assumptions, revealing a broader set of nearby source candidates than found in previous analyses. This application highlights the framework’s ability to translate individual ultra-high-energy cosmic-ray observations into directly interpretable source constraints and provides a foundation for future simulation-based analyses of cosmic rays at the highest energies.

We report Atacama Large Millimeter/submillimeter Array continuum and molecular line observations at 0.1 pc resolution toward the super star cluster (SSC) candidate H72.97−69.39 in the N79 region of the LMC. The continuum emission has a sharp peak around the SSC candidate but is also widely distributed. We identify two continuum sources at the northern (N79S-1) and northwestern (N79S-2) positions of the SSC continuum peak, associated with CH₃OH emission. In addition to CH₃OH, we also detect H₂CO, H₂CS, CS, SO, CO, CN, and CCH at the positions of N79S-1 and N79S-2. The rotation diagram analysis of CH₃OH and SO lines yields an average gas temperature of 13 ± 0.4 K for N79S-1 and 15 ± 0.9 K for N79S-2. Most emission lines exhibit line widths of less than 2.8 km s⁻¹, consistent with emissions from cold, dense molecular cloud cores. The abundance of cold CH₃OH gas is estimated to be (2.1 ± 1.1) × 10⁻⁹ at N79S-1 and (4.5 ± 2.5) × 10⁻¹⁰ at N79S-2. Despite the lower metallicity in the LMC, the CH₃OH abundance at N79S-1 is comparable to that of similar cold sources in our Galaxy. However, the formation of organic molecules is inhibited throughout the N79 regions, as can be seen in the nondetection of CH₃OH in most of the regions. The two positions N79S-1 and N79S-2 would be exceptional positions, where CH₃OH production is efficient. The possible origins of cold CH₃OH gas in these dense cores are discussed, along with a possible explanation for the nondetection of CH₃OH in the SSC candidate.

This study investigates the morphological classification and drifting rate measurement of the repeating fast radio burst (FRB) source FRB 20240114A using the Five-hundred-meter Aperture Spherical Telescope. Detected on 2024 January 14, FRB 20240114A exhibited an exceptionally high burst rate, revealing unique properties. Through observational campaigns over several months, we selected a data set comprising 3203 bursts (2109 burst clusters) during a continuous monitoring session (15,780 s) on 2024 March 12. Improving upon previous work, we clarify the definitions of sub-bursts, bursts, and burst clusters. Using an average dispersion measures of 529.2 pc cm⁻³, we classified the burst clusters into Downward Drifting, Upward Drifting, No Drifting, No Evidence for Drifting, Not-Clear, and Complex burst clusters. Among the 978 burst clusters that exhibit drifting behavior, 233 (23.82%) show upward drifting. Additionally, if 142 upward-drifting single-component burst clusters are excluded, upward-drifting double- and multicomponent burst clusters still account for 10.89% of the 836 burst clusters exhibiting drifting behavior, equating to 91 burst clusters. Furthermore, if only upward-drifting burst clusters with consecutive time intervals (or upward-drifting bursts) are considered, only nine bursts remain. Drifting rate comparisons with other physical quantities reveal that the drifting rate increases with peak frequency for single-component burst clusters with drifting behavior. Moreover, in single-component burst clusters, those with upward drifting exhibit smaller effective widths, bandwidths, and fluxes than their downward-drifting counterparts. A Kolmogorov–Smirnov test further indicates that upward-drifting burst clusters possess longer consecutive time intervals than downward-drifting ones, suggesting distinct underlying physical mechanisms.

Low-luminosityγ-ray bursts (LL GRBs), a subclass of the most powerful transients in the Universe, remain promising sources of high-energy astrophysical neutrinos, despite strong IceCube constraints on typical long GRBs. In this work, a novel approach is introduced to study a sample of seven LL GRBs with their multiwavelength observations to investigate leptohadronic processes during their prompt emission phases. The relative energy densities in magnetic fields, nonthermal electrons, and protons are constrained, with the latter defining the cosmic-ray (CR) loading factor. Our results suggest that LL GRBs exhibit diverse emission processes, as confirmed by a machine learning analysis of the fitted parameters. Across the seven LL GRBs, we find the posterior medians of the CR loading factor to be in the range ofξ_p ∼ 0.2–1.6. GRB 060218 and GRB 100316D, the lowest-luminosity bursts (L_γ,iso ∼ 10⁴⁶–10⁴⁷erg s⁻¹) consistent with the shock-breakout scenario, yield the highest CR loading factors and therefore are expected to produce neutrinos more efficiently. Our model predicts the expected number of neutrino signals that are consistent with current limits but would be detectable with next-generation neutrino observatories. These results strengthen the case for LL GRBs as promising sources of high-energy astrophysical neutrinos and motivate real-time searches for coincident LL GRB and neutrino events. Next-generation X-ray and MeV facilities will be critical for identifying more LL GRBs and strengthening their role in multimessenger astrophysics.

The effective redshift distributionn(z) of galaxies is a critical component in the study of weak gravitational lensing. Here, we introduce a new method for determiningn(z) for weak lensing surveys based on high-quality redshifts and neural-network-based importance weights. Additionally, we present the first unified photometric redshift calibration of the three leading stage-III weak lensing surveys, the Dark Energy Survey (DES), the Hyper Suprime-Cam (HSC) survey, and the Kilo-Degree Survey (KiDS), with state-of-the-art spectroscopic data from the Dark Energy Spectroscopic Instrument (DESI). We verify our method using a new, data-driven approach and obtainn(z) constraints with statistical uncertainties of the order of and smaller. Our analysis is largely independent of previous photometric redshift calibrations and, thus, provides an important cross-check in light of recent cosmological tensions. Overall, we find excellent agreement with previously published results on the DES Y3 and HSC Y1 data sets, while there are some differences on the mean redshift with respect to the previously published KiDS-1000 results. We attribute the latter to mismatches in photometric noise properties in the COSMOS field compared to the wider KiDS self-organizing map-gold catalog. At the same time, the newn(z) estimates for KiDS do not significantly change estimates of cosmic structure growth from cosmic shear. Finally, we discuss how our method can be applied to future weak lensing calibrations with DESI data.

The supernova remnant (SNR) RCW86 is among the few SNRs with Balmer-emission lines containing broad and narrow spectral components that trace fast, nonradiative shocks in partially ionized gas. These are invaluable laboratories for collisionless shock physics, especially for poorly understood phenomena like electron-ion equilibration, and shock precursors. Here we present the first ∼0.3 pc spatial scale integral field unit observations of the southwestern RCW86 shock, obtained as part of the Sloan Digital Sky Survey-V Local Volume Mapper (LVM). The forward shock, clearly visible as thin filaments in narrowband images, exhibits broad component Hα emission, indicating shock velocities varying from 500–900 km s⁻¹ in the south to 1000–1500 km s⁻¹ in the north. The varying velocity widths and broad-to-narrow intensity ratios show that electrons and ions have lower equilibration (T_e/T_p → 0.1) in faster (>800 km s⁻¹) shocks, in line with previous studies. The broad components are generally redshifted from the narrow components by ≲100 km s⁻¹, likely due to shock-obliquity or non-Maxwellian post-shock distributions. We observe high extinction-corrected Balmer-decrements of 3–5 in the narrow components, indicating that conversion of Lyβ photons to Hα is more efficient than Lyγ to Hβ. Upper limits on the HeIIλ4686 in the southern shock are consistent with a moderate-to-high (30%–100%) neutral fraction in the preshock gas. We also find the first evidence of an intermediate Hα component in RCW86, with ΔV(FWHM) = 193–207 km s⁻¹, likely due to a fast neutral precursor. We also briefly discuss the southwestern radiative shock, and lay out the exciting future of studying astrophysical shocks with LVM.

We report measurements of the mass density, Ω_M, and cosmological-constant energy density, Ω_Λ, of the universe based on the analysis of 42 type Ia supernovae discovered by the Supernova Cosmology Project. The magnitude-redshift data for these supernovae, at redshifts between 0.18 and 0.83, are fitted jointly with a set of supernovae from the Calán/Tololo Supernova Survey, at redshifts below 0.1, to yield values for the cosmological parameters. All supernova peak magnitudes are standardized using a SN Ia light-curve width-luminosity relation. The measurement yields a joint probability distribution of the cosmological parameters that is approximated by the relation 0.8Ω_M-0.6Ω_Λ≈-0.2±0.1 in the region of interest (Ω_M≲1.5). For a flat (Ω_M+Ω_Λ=1) cosmology we find Ω_M^flat=0.28^+0.09_-0.08 (1 σ statistical)^+0.05_-0.04 (identified systematics). The data are strongly inconsistent with a Λ=0 flat cosmology, the simplest inflationary universe model. An open, Λ=0 cosmology also does not fit the data well: the data indicate that the cosmological constant is nonzero and positive, with a confidence ofP(Λ>0)=99%, including the identified systematic uncertainties. The best-fit age of the universe relative to the Hubble time ist₀^flat=14.9^+1.4_-1.1(0.63/h) Gyr for a flat cosmology. The size of our sample allows us to perform a variety of statistical tests to check for possible systematic errors and biases. We find no significant differences in either the host reddening distribution or Malmquist bias between the low-redshift Calán/Tololo sample and our high-redshift sample. Excluding those few supernovae that are outliers in color excess or fit residual does not significantly change the results. The conclusions are also robust whether or not a width-luminosity relation is used to standardize the supernova peak magnitudes. We discuss and constrain, where possible, hypothetical alternatives to a cosmological constant.

The Astropy Project supports and fosters the development of open-source and openly developedPython packages that provide commonly needed functionality to the astronomical community. A key element of the Astropy Project is the core packageastropy, which serves as the foundation for more specialized projects and packages. In this article, we summarize key features in the core package as of the recent major release, version 5.0, and provide major updates on the Project. We then discuss supporting a broader ecosystem of interoperable packages, including connections with several astronomical observatories and missions. We also revisit the future outlook of the Astropy Project and the current status of Learn Astropy. We conclude by raising and discussing the current and future challenges facing the Project.

We present measurements of dust reddening using the colors of stars with spectra in the Sloan Digital Sky Survey. We measure reddening as the difference between the measured and predicted colors of a star, as derived from stellar parameters from the Sloan Extension for Galactic Understanding and Exploration Stellar Parameter Pipeline. We achieve uncertainties of 56, 34, 25, and 29 mmag in the colorsu −g,g −r,r −i, andi −z, per star, though the uncertainty varies depending on the stellar type and the magnitude of the star. The spectrum-based reddening measurements confirm our earlier “blue tip” reddening measurements, finding reddening coefficients different by −3%, 1%, 1%, and 2% inu −g,g −r,r −i, andi −z from those found by the blue tip method, after removing a 4% normalization difference. These results prefer anR_V = 3.1 Fitzpatrick reddening law to O'Donnell or Cardelli et al. reddening laws. We provide a table of conversion coefficients from the Schlegel et al. (SFD) maps ofE(B −V) to extinction in 88 bandpasses for four values ofR_V, using this reddening law and the 14% recalibration of SFD first reported by Schlafly et al. and confirmed in this work.

We present constraints on cosmological parameters from the Pantheon+ analysis of 1701 light curves of 1550 distinct Type Ia supernovae (SNe Ia) ranging in redshift fromz = 0.001 to 2.26. This work features an increased sample size from the addition of multiple cross-calibrated photometric systems of SNe covering an increased redshift span, and improved treatments of systematic uncertainties in comparison to the original Pantheon analysis, which together result in a factor of 2 improvement in cosmological constraining power. For a flat ΛCDM model, we find Ω_M = 0.334 ± 0.018 from SNe Ia alone. For a flatw₀CDM model, we measurew₀ = −0.90 ± 0.14 from SNe Ia alone,H₀ = 73.5 ± 1.1 km s⁻¹ Mpc⁻¹ when including the Cepheid host distances and covariance (SH0ES), andw₀ = when combining the SN likelihood with Planck constraints from the cosmic microwave background (CMB) and baryon acoustic oscillations (BAO); bothw₀ values are consistent with a cosmological constant. We also present the most precise measurements to date on the evolution of dark energy in a flatw₀w_aCDM universe, and measurew_a = from Pantheon+ SNe Ia alone,H₀ = 73.3 ± 1.1 km s⁻¹ Mpc⁻¹ when including SH0ES Cepheid distances, andw_a = when combining Pantheon+ SNe Ia with CMB and BAO data. Finally, we find that systematic uncertainties in the use of SNe Ia along the distance ladder comprise less than one-third of the total uncertainty in the measurement ofH₀ and cannot explain the present “Hubble tension” between local measurements and early universe predictions from the cosmological model.

This is the first of a series of papers presenting the Modules for Experiments in Stellar Astrophysics (MESA) Isochrones and Stellar Tracks (MIST) project, a new comprehensive set of stellar evolutionary tracks and isochrones computed using MESA, a state-of-the-art open-source 1D stellar evolution package. In this work, we present models with solar-scaled abundance ratios covering a wide range of ages (), masses (), and metallicities (). The models are self-consistently and continuously evolved from the pre-main sequence (PMS) to the end of hydrogen burning, the white dwarf cooling sequence, or the end of carbon burning, depending on the initial mass. We also provide a grid of models evolved from the PMS to the end of core helium burning for. We showcase extensive comparisons with observational constraints as well as with some of the most widely used existing models in the literature. The evolutionary tracks and isochrones can be downloaded from the project website athttp://waps.cfa.harvard.edu/MIST/.

HEALPix—the Hierarchical Equal Area isoLatitude Pixelization—is a versatile structure for the pixelization of data on the sphere. An associated library of computational algorithms and visualization software supports fast scientific applications executable directly on discretized spherical maps generated from very large volumes of astronomical data. Originally developed to address the data processing and analysis needs of the present generation of cosmic microwave background experiments (e.g., BOOMERANG,WMAP), HEALPix can be expanded to meet many of the profound challenges that will arise in confrontation with the observational output of future missions and experiments, including, e.g.,Planck,Herschel,SAFIR, and the Beyond Einstein inflation probe. In this paper we consider the requirements and implementation constraints on a framework that simultaneously enables an efficient discretization with associated hierarchical indexation and fast analysis/synthesis of functions defined on the sphere. We demonstrate how these are explicitly satisfied by HEALPix.

We present a full-sky 100 μm map that is a reprocessed composite of theCOBE/DIRBE andIRAS/ISSA maps, with the zodiacal foreground and confirmed point sources removed. Before using the ISSA maps, we remove the remaining artifacts from theIRAS scan pattern. Using the DIRBE 100 and 240 μm data, we have constructed a map of the dust temperature so that the 100 μm map may be converted to a map proportional to dust column density. The dust temperature varies from 17 to 21 K, which is modest but does modify the estimate of the dust column by a factor of 5. The result of these manipulations is a map with DIRBE quality calibration andIRAS resolution. A wealth of filamentary detail is apparent on many different scales at all Galactic latitudes. In high-latitude regions, the dust map correlates well with maps of H I emission, but deviations are coherent in the sky and are especially conspicuous in regions of saturation of H I emission toward denser clouds and of formation of H₂ in molecular clouds. In contrast, high-velocity H I clouds are deficient in dust emission, as expected.

To generate the full-sky dust maps, we must first remove zodiacal light contamination, as well as a possible cosmic infrared background (CIB). This is done via a regression analysis of the 100 μm DIRBE map against the Leiden-Dwingeloo map of H I emission, with corrections for the zodiacal light via a suitable expansion of the DIRBE 25 μm flux. This procedure removes virtually all traces of the zodiacal foreground. For the 100 μm map no significant CIB is detected. At longer wavelengths, where the zodiacal contamination is weaker, we detect the CIB at surprisingly high flux levels of 32 ± 13 nW m^-2 sr^-1 at 140 μm and of 17 ± 4 nW m^-2 sr^-1 at 240 μm (95% confidence). This integrated flux ~2 times that extrapolated from optical galaxies in the Hubble Deep Field.

The primary use of these maps is likely to be as a new estimator of Galactic extinction. To calibrate our maps, we assume a standard reddening law and use the colors of elliptical galaxies to measure the reddening per unit flux density of 100 μm emission. We find consistent calibration using theB-R color distribution of a sample of the 106 brightest cluster ellipticals, as well as a sample of 384 ellipticals withB-V and Mg line strength measurements. For the latter sample, we use the correlation of intrinsicB-V versus Mg₂ index to tighten the power of the test greatly. We demonstrate that the new maps are twice as accurate as the older Burstein-Heiles reddening estimates in regions of low and moderate reddening. The maps are expected to be significantly more accurate in regions of high reddening. These dust maps will also be useful for estimating millimeter emission that contaminates cosmic microwave background radiation experiments and for estimating soft X-ray absorption. We describe how to access our maps readily for general use.

We present cosmological parameter measurements from the Deep Lens Survey (DLS) using galaxy–mass and galaxy–galaxy power spectra in the multipole rangeℓ = 250–2000. We measure galaxy–galaxy power spectra from two lens bins centered atz ∼ 0.27 and 0.54 and galaxy–mass power spectra by cross-correlating the positions of galaxies in these two lens bins with galaxy shapes in two source bins centered atz ∼ 0.64 and 1.1. We marginalize over a baryonic feedback process using a single-parameter representation and a sum of neutrino masses, as well as photometric redshift and shear calibration systematic uncertainties. For a flat ΛCDM cosmology, we determine, in good agreement with our previous DLS cosmic shear and thePlanck cosmic microwave background (CMB) measurements. Without the baryonic feedback marginalization,S₈ decreases by because the dark-matter-only power spectrum lacks the suppression at the highestℓ values owing to active galactic nucleus (AGN) feedback. Together with thePlanck CMB measurements, we constrain the baryonic feedback parameter to, which suggests an interesting possibility that the actual AGN feedback might be stronger than the recipe used in the OverWhelmingly Large cosmological hydrodynamical Simulations. The interpretation is limited by the validity of the baryonic feedback simulation and the one-parameter representation of the effect.

We present the large-scale correlation function measured from a spectroscopic sample of 46,748 luminous red galaxies from the Sloan Digital Sky Survey. The survey region covers 0.72h^-3 Gpc³ over 3816 deg² and 0.16 <z < 0.47, making it the best sample yet for the study of large-scale structure. We find a well-detected peak in the correlation function at 100h^-1 Mpc separation that is an excellent match to the predicted shape and location of the imprint of the recombination-epoch acoustic oscillations on the low-redshift clustering of matter. This detection demonstrates the linear growth of structure by gravitational instability betweenz ≈ 1000 and the present and confirms a firm prediction of the standard cosmological theory. The acoustic peak provides a standard ruler by which we can measure the ratio of the distances toz = 0.35 andz = 1089 to 4% fractional accuracy and the absolute distance toz = 0.35 to 5% accuracy. From the overall shape of the correlation function, we measure the matter density Ω_mh² to 8% and find agreement with the value from cosmic microwave background (CMB) anisotropies. Independent of the constraints provided by the CMB acoustic scale, we find Ω_m = 0.273 ± 0.025 + 0.123(1 +w₀) + 0.137Ω_K. Including the CMB acoustic scale, we find that the spatial curvature is Ω_K = -0.010 ± 0.009 if the dark energy is a cosmological constant. More generally, our results provide a measurement of cosmological distance, and hence an argument for dark energy, based on a geometric method with the same simple physics as the microwave background anisotropies. The standard cosmological model convincingly passes these new and robust tests of its fundamental properties.

Here we present 1701 light curves of 1550 unique, spectroscopically confirmed Type Ia supernovae (SNe Ia) that will be used to infer cosmological parameters as part of the Pantheon+ SN analysis and the Supernovae andH₀ for the Equation of State of dark energy distance-ladder analysis. This effort is one part of a series of works that perform an extensive review of redshifts, peculiar velocities, photometric calibration, and intrinsic-scatter models of SNe Ia. The total number of light curves, which are compiled across 18 different surveys, is a significant increase from the first Pantheon analysis (1048 SNe), particularly at low redshift (z). Furthermore, unlike in the Pantheon analysis, we include light curves for SNe withz < 0.01 such that SN systematic covariance can be included in a joint measurement of the Hubble constant (H₀) and the dark energy equation-of-state parameter (w). We use the large sample to compare properties of 151 SNe Ia observed by multiple surveys and 12 pairs/triplets of “SN siblings”—SNe found in the same host galaxy. Distance measurements, application of bias corrections, and inference of cosmological parameters are discussed in the companion paper by Brout et al., and the determination ofH₀ is discussed by Riess et al. These analyses will measurew with ∼3% precision and H₀ with ∼1 km s⁻¹ Mpc⁻¹ precision.