Effortless reconstructs Roman images 50–60× faster than Imcom; one calibrated single-image output beats ~6 coadded Imcom images on ideal point-source moments.
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HEALPix -- a Framework for High Resolution Discretization, and Fast Analysis of Data Distributed on the Sphere
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abstract
HEALPix -- the Hierarchical Equal Area iso-Latitude Pixelization -- is a versatile data structure with an associated library of computational algorithms and visualization software that supports fast scientific applications executable directly on very large volumes of astronomical data and large area surveys in the form of discretized spherical maps. Originally developed to address the data processing and analysis needs of the present generation of cosmic microwave background (CMB) 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 CMB polarization probe. In this paper we consider the requirements and constraints to be met in order to implement a sufficient framework for the efficient discretization and fast analysis/synthesis of functions defined on the sphere, and summarise how they are satisfied by HEALPix.
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- abstract HEALPix -- the Hierarchical Equal Area iso-Latitude Pixelization -- is a versatile data structure with an associated library of computational algorithms and visualization software that supports fast scientific applications executable directly on very large volumes of astronomical data and large area surveys in the form of discretized spherical maps. Originally developed to address the data processing and analysis needs of the present generation of cosmic microwave background (CMB) experiments (e.g. BOOMERanG, WMAP), HEALPix can be expanded to meet many of the profound challenges that will aris
- method 0 scenario [31] with time-varying greenhouse gas and ozone concentrations. ICON started 1 January 2020 at approximately 10 km atmospheric and 5 km oceanic resolution; IFS-FESOM started 20 January 2020 at approximately 9 km atmospheric and 5 km oceanic resolution. Output was post-processed onto a Hierarchical Equal Area IsoLatitude Pixelation (HEALPix) grid [32] at∼12.7 km horizontal resolution. 2.2 K¨ oppen-Geiger climate classification We use the K¨ oppen-Geiger classification as described in [
- background 08022]. [45] H. Li, S.-Y. Li, Y. Liu, Y.-P. Li, Y. Cai, M. Li et al.,Probing Primordial Gravitational Waves: Ali CMB Polarization Telescope,Natl. Sci. Rev.6(2019) 145 [1710.03047]. [46] M. Hazumi et al.,LiteBIRD: A Satellite for the Studies of B-Mode Polarization and Inflation from Cosmic Background Radiation Detection,J. Low Temp. Phys.194(2019) 443. [47] C. Chiocchetta, A. Gruppuso, M. Lattanzi, P. Natoli and L. Pagano,Lack-of-correlation anomaly in CMB large scale polarisation maps,JCAP08(202
- method 500 snapshots are stored, linearly spaced in scale factor 15. halos are also identified and used in the baryonification process, which we detail in Section 3.3. We build past lightcones by discretizing the volume around an observer into concentric shells, computing the projected density of particles in each of those shells, and storing them on Healpixmaps [65, 66] 16 with anNsideof 8192. This resolution corresponds to a physical scale of 0.43 arcmin or 26 arcsec. The lightcone construction proce
- method parameters, the marginal widths ∆λand ∆βalone are not sufficient to fully capture the two-dimensional poste- rior structure, especially when the sky posterior exhibits clear multimodality. In such cases, the sky area provides a more direct measure of the overall geometric extent of the localization region. In this work, the sky area is com- puted using a HEALPix-based pixelization scheme [65], with implementation details given in Appendix B. The corresponding parameter-precision, divergence, and
- background 8 ˚A for all fibers and exposures, which simplifies the co-addition (or averaging) of spectra from the same target obtained in different exposures. The data pro- cessing pipeline provides 2 sets of co-added spectra, one per spectrograph and tile, combining data of several exposures and nights for the same pointing and fiber allocation, and one per HEALPix pixel [42] on the sky where the full co-added spectra (across exposures and tiles) of all the targets in a HEALPix pixel are saved. We use thi
- background E[d] =WE[a] +E[ϵ] =Wµ a,(19) Cov(d) = Cov(Wa) + Cov(ϵ) =WΣ a W T + Σd.(20) Hence, p(d|θ) =N d Wµ a, WΣ a W T + Σd ,(21) so that marginalization over the high-dimensional sur- face map is available in closed form without explicitly computing any integrals. The posterior distribution of the nonlinear parameters θfollows from Bayes' theorem: p(θ|d)∝p(d|θ)p(θ),(22) wherep(d|θ) is the marginal likelihood in Eq. (21), andp(θ) denotes the prior on the nonlinear parameters. Bayesian Doppler Imaging5
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The authors derive the fourth-order galaxy-galaxy lensing 4PCF and aperture statistics, implement a numerical pipeline and FFT estimator, and detect the connected ⟨N³ M_ap⟩ signal at SNR ~9 in stage IV mock data over 2000 deg².
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Adding a fitted radio-emission component to tSZ×galaxy cross-spectra removes an apparent negative small-scale signal and yields spectra consistent with a standard halo model (9.5–11σ BIC preference for the radio term).
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Auriga simulations show the LMC induces azimuthal anisotropies in directional DM recoils that enhance discovery prospects relative to the Standard Halo Model.
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A divide-and-conquer framework using QAOA and neural network surrogates accelerates constrained MCMC by factors of 7.6 to 20.3 over classical methods.
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citing papers explorer
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Efficient Optimal Image Reconstruction for the Nancy Grace Roman Space Telescope and Beyond: I. First Results with {\sc Effortless}
Effortless reconstructs Roman images 50–60× faster than Imcom; one calibrated single-image output beats ~6 coadded Imcom images on ideal point-source moments.
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DIffuse X-ray Explorer (DIXE): Sky Survey Strategy and Collimator Response Demodulation
DIXE proposes CSS-based survey strategies covering 72.5% of the sky with 26-68 ks exposures and shows via simulation that MCMC collimator demodulation yields 1° point-source localization and 3° extended-source resolution.
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Polarized Anisotropic Stochastic Gravitational Wave Background Search with Ground-Based Detector Networks
Implements full-Stokes SGWB map-making for ground-based networks, applies to LVK O3 data, and constrains polarized angular spectra while showing intensity-only models can be biased.
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Bayesian Doppler Imaging: Simultaneous Inference of Surface Maps and Geometric Parameters
A fully Bayesian pixel-based Doppler imaging framework uses Gaussian Process priors and Hamiltonian Monte Carlo to simultaneously infer surface maps and geometric parameters from spectral data.
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AIMIP Phase 1: systematic evaluations of AI weather and climate models
Under one protocol, most AI climate models reproduce historical climatology and ENSO response as well as a CMIP6 model, but some underestimate warming trends and all diverge on +2/+4K SST experiments.
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Forecasting graviton-mass constraints from the full covariance of PTA-astrometry ORF estimators
A full-covariance formalism for PTA-astrometry ORF estimators forecasts graviton-mass upper limits of 4.41e-24 eV/c2 for current-like setups and 0.48e-24 eV/c2 for SKA/Theia-like future setups, with astrometry adding significant power in the latter case.
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Archival Multiband Gravitational-Wave Signals from Massive Black Hole Binary Mergers
Massive black hole binary mergers produce orphaned low-frequency signals in PTA pulsar terms that can be stacked for archival multiband gravitational-wave detection.
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Fourth-order galaxy-galaxy-lensing: Theoretical framework and direct estimation
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Non-Gaussianity in SMICA
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Deep Learning for CMB Foreground Removal and Beam Deconvolution: A U-Net GAN Approach
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Milky Way Atlas: A radial-velocity-resolved, three-dimensional map of H I within 1.25 kpc
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Robust CMB polarisation mapmaking with a rotating half-wave plate
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Thermal Sunyaev-Zel'dovich cross-correlations with unWISE galaxies: disentangling radio contamination, dust properties, and electron pressure
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Cross-correlation of SPT-3G D1 CMB lensing and DES Y3 galaxy lensing
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Directional dark matter signatures of the Large Magellanic Cloud
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Dark Energy Survey Year 3 results: optimized $w$CDM simulation-based inference with weak lensing map-level hybrid statistics
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Radio sirens: inferring $H_0$ with binary black holes and neutral hydrogen in the era of the Einstein Telescope and the SKA Observatory
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Parameter Estimation of the Gravitational-Wave Angular Power Spectrum in the Dirty-Map Space
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HealDA: Highlighting the importance of initial errors in end-to-end AI weather forecasts
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Efficient Search for Detection Candidates Using a Peak Finder Strategy for All-Sky-All-Frequency Gravitational Wave Radiometer
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The first AKRA mass map reconstruction from HSC Y1 data
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Robust Measurement of Stellar Streams Around the Milky Way: Correcting Spatially Variable Observational Selection Effects in Optical Imaging Surveys
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QML-FAST -- A Fast Code for low-$\ell$ Tomographic Maximum Likelihood Power Spectrum Estimation
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Constraining Inflationary Particle Production with CMB Polarization
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Probing the limits of cosmological information from the Lyman-$\alpha$ forest 2-point correlation functions
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Lya2pcf: an efficient pipeline to estimate two- and three-point correlation functions of the Lyman-$\alpha$ forest
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Cosmic filaments confirm unexplained CMB temperature decrements in two independent redshift ranges
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Reconstructing the Thermal Sunyaev Zeldovich Power Spectrum from Planck using the ABS Method
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Modeling and measuring the anisotropic halo 3-point correlation function: a coordinated study
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DESI 2024 IV: Baryon Acoustic Oscillations from the Lyman Alpha Forest
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The Atacama Cosmology Telescope: DR6 Gravitational Lensing Map and Cosmological Parameters
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The Atacama Cosmology Telescope: A Measurement of the DR6 CMB Lensing Power Spectrum and its Implications for Structure Growth
ACT DR6 yields a 2.3% precise CMB lensing power spectrum with A_lens = 1.013 ± 0.023 relative to Planck 2018 Lambda CDM, giving S8 = 0.818 ± 0.022 and no evidence for suppressed structure growth.
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Estimating distances from parallaxes. V: Geometric and photogeometric distances to 1.47 billion stars in Gaia Early Data Release 3
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First Results from the TNG50 Simulation: Galactic outflows driven by supernovae and black hole feedback
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CMB Lensing Reconstruction Using Two Years of Temperature Data from the SPT-3G Summer Survey
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Impact of inhomogeneous curvature on growth rate measurements from magnitude fluctuations
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HETDEX Public Data Release 1: Source Catalog 2 and Data Cubes from ~90 sq deg of Integral-Field Optical Spectroscopy
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The Ellis and Baldwin test of the Cosmic Dipole: Exploring the impact of multiple flux density cuts
A multi-bin simultaneous dipole fitting method yields higher Bayes factors than single flux-cut approaches for non-power-law luminosity functions in cosmic dipole measurements.
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$4\times3$ Point Correlation Functions in Galaxy Surveys: Impact of Baryonic Feedback
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Pre-localization of Massive Black Hole Binaries in the Millihertz Band
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Extending Galactic foreground emission with neural networks
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Blind mitigation of foreground-induced biases on primordial $B$ modes for ground-based CMB experiments
Two NILC extensions—one deprojecting foreground moments and one marginalizing residuals at the likelihood level—yield unbiased r estimates and consistent lensing B-mode reconstruction in SO-SAT-like simulations.
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Expectations for the first supermassive black-hole binary resolved by PTAs II: Milestones for binary characterization
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