Results 2501-2600 of 3429 (3345 ASCL, 84 submitted)

[ascl:1304.016]
Qhull: Quickhull algorithm for computing the convex hull

Qhull computes the convex hull, Delaunay triangulation, Voronoi diagram, halfspace intersection about a point, furthest-site Delaunay triangulation, and furthest-site Voronoi diagram. The source code runs in 2-d, 3-d, 4-d, and higher dimensions. Qhull implements the Quickhull algorithm for computing the convex hull. It handles roundoff errors from floating point arithmetic. It computes volumes, surface areas, and approximations to the convex hull.

[ascl:1908.020]
QLF: Luminosity function analysis code

QLF derives full posterior distributions for and analyzes luminosity functions models; it also models hydrogen and helium reionization. Used with the included homogenized data, the derived luminosity functions can be easily compared with theoretical models or future data sets.

[submitted]
qmatch: Some astronomical image matching programs

Matching stars in astronomical images is an essential step in data reduction. This work includes some matching programs implemented by Python: simple matching, fast matching, and triangle matching. For two catalogs with m and n objects, the simple method has a time and space complexity of O(m*n) but is fast for fewer n or m. The time complexity of the fast method is O(mlogm+nlogn). The triangle method will work between rotated and scaled images. All methods are applied in pipelines and work well. This package is published to the PyPI with the name 'qmatch'.

[ascl:1910.022]
qnm: Kerr quasinormal modes, separation constants, and spherical-spheroidal mixing coefficients calculator

qnm computes the Kerr quasinormal mode frequencies, angular separation constants, and spherical-spheroidal mixing coefficients. The qnm package includes a Leaver solver with the Cook-Zalutskiy spectral approach to the angular sector, and a caching mechanism to avoid repeating calculations. A large cache of low ℓ, m, n modes is available for download and can be installed with a single function call and interpolated to provide good initial guess for root-polishing at new values of spin.

[ascl:1809.011]
qp: Quantile parametrization for probability distribution functions

qp manipulates parametrizations of 1-dimensional probability distribution functions, as suitable for photo-z PDF compression. The code helps determine a parameterization for storing a catalog of photo-z PDFs that balances the available storage resources against the accuracy of the photo-z PDFs and science products reconstructed from the stored parameters.

[ascl:2208.002]
qrpca: QR-based Principal Components Analysis

qrpca uses QR-decomposition for fast principal component analysis. The software is particularly suited for large dimensional matrices. It makes use of torch for internal matrix computations and enables GPU acceleration, when available. Written in both R and python languages, qrpca provides functionalities similar to the prcomp (R) and sklearn (python) packages.

[ascl:1612.011]
QSFit: Quasar Spectral FITting

QSFit performs automatic analysis of Active Galactic Nuclei (AGN) optical spectra. It provides estimates of: AGN continuum luminosities and slopes at several restframe wavelengths; luminosities, widths and velocity offsets of 20 emission lines; luminosities of iron blended lines at optical and UV wavelengths; host galaxy luminosities. The whole fitting process is customizable for specific needs, and can be extended to analyze spectra from other data sources. The ultimate purpose of QSFit is to allow astronomers to run standardized recipes to analyze the AGN data, in a simple, replicable and shareable way.

[ascl:2205.003]
QSOGEN: Model quasar SEDs

The QSOGEN collection of Python code models quasar colors, magnitudes and SEDs. It implements an empirically-motivated parametric model to efficiently account for the observed emission-line properties, host-galaxy contribution, dust reddening, hot dust emission, and IGM suppression in the rest-frame 900-30000A wavelength range for quasars with a wide range of redshift and luminosity.

The code is packaged with a set of empirically-derived emission-line templates and an empirically-derived quasar dust extinction curve which are publicly released.

[ascl:1912.011]
QSOSIM: Simulated Quasar Spectrum Generator

QSOSIM realistically simulates high-resolution quasar spectra using a set of basic parameters (magnitude, redshift, and spectral index). The simulated spectra include physical effects seen in the real data: the power-law quasar continuum, the narrow and broad emission lines, absorption by neutral hydrogen (HI) in the Lyman alpha forest, and heavy element transitions along the line of sight. The code uses empirical HI column density, redshift, and b-parameter distributions to simulate absorption in the Lyman alpha forest. All absorbers with column densities larger than log [N(HI)/cm^{2}]>17 have heavy element absorption, for which the column densities are calculated using the plasma simulation code CLOUDY (ascl:9910.001) and the radiative transfer code CUBA. The code also simulates the clustering of the intergalactic medium along the line of sight, the proximity effect of the quasar, and the effect of the cosmic ultraviolet background. Each simulated spectrum is saved in a single FITS file in as a noiseless R=100000 spectrum, as well as a spectrum convolved with Sloan Digital Sky Survey resolution (R=10000) and realistic noise.

[ascl:1703.011]
QtClassify: IFS data emission line candidates classifier

QtClassify is a GUI that helps classify emission lines found in integral field spectroscopic data. Input needed is a datacube as well as a catalog with emission lines and a signal-to-noise cube, such at that created by LSDCat (ascl:1612.002). The main idea is to take each detected line and guess what line it could be (and thus the redshift of the object). You would expect to see other lines that might not have been detected but are visible in the cube if you know where to look, which is why parts of the spectrum are shown where other lines are expected. In addition, monochromatic layers of the datacube are displayed, making it easy to spot additional emission lines.

[ascl:2401.017]
QuantifAI: Radio interferometric imaging reconstruction with scalable Bayesian uncertainty quantification

Liaudat, Tobías I.; Mars, Matthijs; Price, Matthew A.; Pereyra, Marcelo; Betcke, Marta M.; McEwen, Jason D.

QuantifAI reconstructs radio interferometric images using scalable Bayesian uncertainty quantification relying on data-driven (learned) priors. It relies on the convex accelerated optimization algorithms in CRR (ascl:2401.016) and is built on top of PyTorch. QuantifAI also includes MCMC algorithms for posterior sampling.

[ascl:2305.006]
QuartiCal: Fast radio interferometric calibration

QuartiCal is the successor to CubiCal (ascl:1805.031). It implements a suite of fast radio interferometric calibration routines exploiting complex optimization. Unlike CubiCal, QuartiCal allows for any available Jones terms to be combined. It can also be deployed on a cluster.

[ascl:2106.016]
QuasarNET: CNN for redshifting and classification of astrophysical spectra

QuasarNET is a deep convolutional neural network that performs classification and redshift estimation of astrophysical spectra with human-expert accuracy. It is trained on data of low signal-to-noise and medium resolution, typical of current and future astrophysical surveys, and could be easily applied to classify spectra from current and upcoming surveys such as eBOSS, DESI and 4MOST.

[ascl:2005.013]
qubefit: MCMC kinematic modeling

qubefit fits an observed data cube to generate a model cube from a user-defined emission model. The model cube is convolved with the observed beam, after which residuals between the convolved model and the observed data cube are minimized using a Markov chain Monte Carlo approach. qubefit also determines estimates of the uncertainty for each parameter of the model.

[ascl:2112.002]
QUESTFIT: Fitter for mid-infrared galaxy spectra

Rupke, D. S. N.; Schweitzer, M.; Viola, V.; Lutz, D.; Sturm, E.; Spoon, H.; Veilleux, S.; Kim, D.-C.

QUESTFIT fit the Spitzer mid-infrared spectra of the QUEST (Quasar ULIRG and Evolution STudy) sample. It uses two PAH templates atop an extincted and absorbed continuum model to fit the mid-IR spectra of galaxies that are heavily-absorbed. It also fits AGN with silicate models. The current version of QUESTFIT is optimized for processing spectra from the CASSIS (Combined Atlas of Sources with Spitzer IRS Spectra) portal to produce PAH fluxes for heavily absorbed sources.

[ascl:2103.014]
QuickCBC: Rapid and reliable inference for binary mergers

QuickCBC is a robust end-to-end low-latency Bayesian parameter estimation algorithm for binary mergers. It reads in calibrated strain data, performs robust on-source spectral estimation, executes a rapid search for compact binary coalescence (CBC) signals, uses wavelet de-noising to subtract any glitches from the search residuals, produces low-latency sky maps and initial parameter estimates, followed by full Bayesian parameter estimation.

[ascl:1704.006]
Quickclump: Identify clumps within a 3D FITS datacube

Quickclump finds clumps in a 3D FITS datacube. It is a fast, accurate, and automated tool written in Python. Though Quickclump is primarily intended for decomposing observations of interstellar clouds into individual clumps, it can also be used for finding clumps in any 3D rectangular data.

[ascl:1402.012]
QUICKCV: Cosmic variance calculator

QUICKCV is an IDL sample variance/cosmic variance calculator for some geometry for galaxies in given stellar mass bins as a function of mean redshift and redshift bin size.

[ascl:1402.024]
QuickReduce: Data reduction pipeline for the WIYN One Degree Imager

QuickReduce quickly reduces data for ODI and is optimized for a first data inspection during acquisition at the the telescope. When installed on the ODI observer's interface, QuickReduce, coded in Python, performs all basic reduction steps as well as more advanced corrections for pupil-ghost removal, fringe correction and masking of persistent pixels and is capable enough for science-quality data reductions. It can also add an accurate astrometric WCS solution based on the 2MASS reference system as well as photometric zeropoint calibration for frames covered by the SDSS foot-print. The pipeline makes use of multiple CPU-cores wherever possible, resulting in an execution time of only a few seconds per frame, thus offering the ODI observer a convenient way to closely monitor data quality.

[ascl:1811.006]
QuickSip: Project survey image properties onto the sky into Healpix maps

QuickSip quickly projects Survey Image Properties (e.g. seeing, sky noise, airmass) into Healpix sky maps with flexible weighting schemes. It was initially designed to produce observing condition "systematics" maps for the Dark Energy Survey (DES), but will work with any multi-epoch survey and images with valid WCS. QuickSip can reproduce the Mangle (ascl:1202.005) magnitude limit maps at sub-percent accuracy but doesn't support additional masks (stars, trails, etc), in which case Mangle should be used. Thus, QuickSip can be seen as a simplified Mangle to project image properties into Healpix maps in a fast and more flexible manner.

[ascl:2110.009]
Quokka: Two-moment AMR radiation hydrodynamics on GPUs for astrophysics

Quokka is a two-moment radiation hydrodynamics code that uses the piecewise-parabolic method, with AMR and subcycling in time. It runs on CPUs (MPI+vectorized) or NVIDIA GPUs (MPI+CUDA) with a single-source codebase. The hydrodynamics solver is an unsplit method, using the piecewise parabolic method for reconstruction in the primitive variables, the HLLC Riemann solver for flux computations, and a method-of-lines formulation for the time integration. The order of reconstruction is reduced in zones where shocks are detected in order to suppress spurious oscillations in strong shocks. Quokka's radiation hydrodynamics formulation is based on the mixed-frame moment equations. The radiation subsystem is coupled to the hydrodynamic subsystem via operator splitting, with the hydrodynamic update computed first, followed by the radiation update, with the latter update including the source terms corresponding to the radiation four-force applied to both the radiation and hydrodynamic variables. A method-of-lines formulation is also used for the time integration, with the time integration done by the same integrator chosen for the hydrodynamic subsystem.

[ascl:2112.013]
Qwind: Non-hydrodynamical model for AGN line-drive winds

Quera-Bofarull, Arnau; Done, Chris; Lacey, Cedric; McDowell, Jonathan C.; Risaliti, Guido; Elvis, Martin

Qwind simulates the launching and acceleration phase of line-driven winds in the context of AGN accretion discs. The wind is modeled as a set of streamlines originating on the surface of the AGN accretion disc, and evolved following their equation of motion, given by the balance between radiative and gravitational force.

[ascl:2112.014]
Qwind3: Modeling UV line-driven winds originating from accretion discs

Qwind3 models radiation-driven winds originating from accretion discs. An improvement over Qwind (ascl:2112.013), it derives the wind initial conditions and has significantly improved ray-tracing to calculate the wind absorption self consistently given the extended nature of the UV emission. It also corrects the radiation flux for relativistic effects, and assesses the impact of this on the wind velocity.

[ascl:1210.028]
QYMSYM: A GPU-accelerated hybrid symplectic integrator

QYMSYM is a GPU accelerated 2nd order hybrid symplectic integrator that identifies close approaches between particles and switches from symplectic to Hermite algorithms for particles that require higher resolution integrations. This is a parallel code running with CUDA on a video card that puts the many processors on board to work while taking advantage of fast shared memory.

[ascl:1104.009]
r-Java: An r-process Code and Graphical User Interface for Heavy-Element Nucleosynthesis

r-Java performs r-process nucleosynthesis calculations. It has a simple graphical user interface and is carries out nuclear statistical equilibrium (NSE) as well as static and dynamic r-process calculations for a wide range of input parameters. r-Java generates an abundance pattern based on a general entropy expression that can be applied to degenerate as well as non-degenerate matter, which allows tracking of the rapid density and temperature evolution of the ejecta during the initial stages of ejecta expansion.

[ascl:1106.005]
R3D: Reduction Package for Integral Field Spectroscopy

R3D was developed to reduce fiber-based integral field spectroscopy (IFS) data. The package comprises a set of command-line routines adapted for each of these steps, suitable for creating pipelines. The routines have been tested against simulations, and against real data from various integral field spectrographs (PMAS, PPAK, GMOS, VIMOS and INTEGRAL). Particular attention is paid to the treatment of cross-talk.

R3D unifies the reduction techniques for the different IFS instruments to a single one, in order to allow the general public to reduce different instruments data in an homogeneus, consistent and simple way. Although still in its prototyping phase, it has been proved to be useful to reduce PMAS (both in the Larr and the PPAK modes), VIMOS and INTEGRAL data. The current version has been coded in Perl, using PDL, in order to speed-up the algorithm testing phase. Most of the time critical algorithms have been translated to C, and it is our intention to translate all of them. However, even in this phase R3D is fast enough to produce valuable science frames in reasonable time.

[ascl:1502.013]
Rabacus: Analytic Cosmological Radiative Transfer Calculations

Rabacus performs analytic radiative transfer calculations in simple geometries relevant to cosmology and astrophysics; it also contains tools to calculate cosmological quantities such as the power spectrum and mass function. With core routines written in Fortran 90 and then wrapped in Python, the execution speed is thousands of times faster than equivalent routines written in pure Python.

[ascl:1711.015]
rac-2d: Thermo-chemical for modeling water vapor formation in protoplanetary disks

rec-2d models the distribution of water vapor in protoplanetary disks. Given a distribution of gas and dust, rac-2d first solves the dust temperature distribution with a Monte Carlo method and then solves the gas temperature distribution and chemical composition. Although the geometry is symmetric with respect to rotation around the central axis and reflection about the midplane, the photon propagation is done in full three dimensions. After establishing the dust temperature distribution, the disk chemistry is evolved for 1 Myr; the heating and cooling processes are coupled with chemistry, allowing the gas temperature to be evolved in tandem with chemistry based on the heating and cooling rates.

[ascl:1010.075]
Radex: Fast Non-LTE Analysis of Interstellar Line Spectra

The large quantity and high quality of modern radio and infrared line observations require efficient modeling techniques to infer physical and chemical parameters such as temperature, density, and molecular abundances. Radex calculates the intensities of atomic and molecular lines produced in a uniform medium, based on statistical equilibrium calculations involving collisional and radiative processes and including radiation from background sources. Optical depth effects are treated with an escape probability method. The program makes use of molecular data files maintained in the Leiden Atomic and Molecular Database (LAMDA), which will continue to be improved and expanded. The performance of the program is compared with more approximate and with more sophisticated methods. An Appendix provides diagnostic plots to estimate physical parameters from line intensity ratios of commonly observed molecules. This program should form an important tool in analyzing observations from current and future radio and infrared telescopes.

[ascl:1806.017]
RadFil: Radial density profile builder for interstellar filaments

RadFil is a radial density profile building and fitting tool for interstellar filaments. The software uses an image array and (in most cases) a boolean mask array that delineates the boundary of the filament to build and fit a radial density profile for the filaments.

[ascl:1108.014]
RADICAL: Multi-purpose 2-D Radiative Transfer Code

RADICAL is a multi-purpose 2-D radiative transfer code for axi-symmetric circumstellar (or circum-black-hole) envelopes /disks / tori etc. It has been extensively tested and found reliable and accurate. The code has recently been supplemented with a Variable Eddington Tensor module which enables it to solve dust continuum radiative transfer problems from very low up to extremely high optical depths with only a few (about 7) iterations at most.

[ascl:2104.022]
RadioFisher: Fisher forecasting for 21cm intensity mapping and spectroscopic galaxy surveys

RadioFisher is a Fisher forecasting code for cosmology with intensity maps of the redshifted 21cm emission line of neutral hydrogen. It uses CAMB (ascl:1102.026) to produce a high-resolution P(k) for the fiducial cosmology when the code is first run and caches the results, making subsequent runs faster and more efficient. It includes specifications for a large number of experiments, as well as survey parameters and the fiducial cosmological parameters, and can run a forecast for a galaxy redshift survey rather than an IM survey. RadioFisher also contains a number of options for plotting results.

[ascl:2208.019]
RadioLensfit: Radio weak lensing shear measurement in the visibility domain

RadioLensfit measures star-forming galaxy ellipticities using a Bayesian model fitting approach. The software uses an analytical exponential Sersic model and works in the visibility domain avoiding Fourier Transform. It also simulates visibilities of observed SF galaxies given a source catalog and Measurement Sets containing the description of the radio interferometer and of the observation. It provides both serial and MPI versions.

[ascl:2101.004]
radiowinds: Radio emission from stellar winds

radiowinds calculates the radio emission produced by the winds around stars. The code calculates thermal bremsstrahlung that is emitted from the wind, which depends directly on the density and temperature of the stellar wind plasma. The program takes input data in the form of an interpolated 3d grid of points (of the stellar wind) containing position, temperature and density data. From this it calculates the thermal free-free emission expected from the wind at a range of user-defined frequencies.

[ascl:2312.033]
RADIS: Fast line-by-line code for high-resolution infrared molecular spectra

Pannier, E.; Laux, C.O.; van den Bekerom, D.C.M.; Minesi, N.; Soref, J.; Kumar, A.; Misra, P.; Verma, S.; Grimaldi, C.; Sharma, S.; Huy, T.H.N.; Aryan, G.; Kawahara, H.

RADIS resolves spectra with millions of lines within seconds on a single-CPU and can be GPU-accelerated. It supports HITRAN, HITEMP and ExoMol out-of-the-box (auto-download), and therefore is particularly suitable to compute cross-sections or transmission spectra at high-temperature. RADIS includes equilibrium calculations for all species, and non-LTE for CO2 and CO.

[ascl:1308.012]
RADLite: Raytracer for infrared line spectra

RADLite is a raytracer that is optimized for producing infrared line spectra and images from axisymmetric density structures, originally developed to function on top of the dust radiative transfer code RADMC. RADLite can consistently deal with a wide range of velocity gradients, such as those typical for the inner regions of protoplanetary disks. The code is intended as a back-end for chemical and excitation codes, and can rapidly produce spectra of thousands of lines for grids of models for comparison with observations. It includes functionality for simulating telescopic images for optical/IR/midIR/farIR telescopes. It takes advantage of multi-threaded CPUs and includes an escape-probability non-LTE module.

[ascl:1202.015]
RADMC-3D: A multi-purpose radiative transfer tool

Dullemond, C. P.; Juhasz, A.; Pohl, A.; Sereshti, F.; Shetty, R.; Peters, T.; Commercon, B.; Flock, M.

RADMC-3D is a software package for astrophysical radiative transfer calculations in arbitrary 1-D, 2-D or 3-D geometries. It is mainly written for continuum radiative transfer in dusty media, but also includes modules for gas line transfer and gas continuum transfer. RADMC-3D is a new incarnation of the older software package RADMC (ascl:1108.016).

[ascl:1108.016]
RADMC: A 2-D Continuum Radiative Transfer Tool

RADMC is a 2-D Monte-Carlo code for dust continuum radiative transfer circumstellar disks and envelopes. It is based on the method of Bjorkman & Wood (ApJ 2001, 554, 615), but with several modifications to produce smoother results with fewer photon packages.

[ascl:1811.015]
radon: Streak detection using the Fast Radon Transform

radon performs a Fast Radon Transform (FRT) on image data for streak detection. The software finds short streaks and multiple streaks, convolves the images with a given PSF, and tracks the best S/N results and find a automatic threshold. It also calculates the streak parameters in the input image and the streak parameters in the input image. radon has a simulator that can make multiple streaks of different intensities and coordinates, and can simulate random streaks with parameters chosen uniformly in a user-defined range.

[ascl:9910.009]
RADPACK: A RADical compression analysis PACKage for fitting to the CMB

The RADPACK package, written in IDL, contains both data and software. The data are the constraints on the cosmic microwave background (CMB) angular power spectrum from all published data as of 9/99. A unique aspect of this compilation is that the non-Gaussianity of the uncertainties has been characterized. The most important program in the package, written in the IDL language, is called chisq.pro and calculates $chi^2$, for an input power spectrum, according to the offset log-normal form of Bond, Jaffe and Knox (astro-ph/9808264). chisq.pro also outputs files that are useful for examining the residuals (the difference between the predictions of the model and the data). There is an sm macro for plotting up the residuals, and a histogram of the residuals. The histogram is actually for the 'whitenend' residuals ---a linear combination of the residuals which leaves them uncorrelated and with unit variance. The expectation is that the whitened residuals will be distributed as a Gaussian with unit variance.

[ascl:2210.008]
RADTRAN: General purpose planetary radiative transfer model

RADTRAN calculates the transmission, absorption or emission spectra emitted by planetary atmospheres using either line-by-line integration, spectral band models, or 'correlated-K' approaches. Part of the NEMESIS project (ascl:2210.009), the code also incorporates both multiple scattering and single scattering calculations. RADTRAN is general purpose and not hard-wired to any specific planet.

[ascl:1801.012]
RadVel: General toolkit for modeling Radial Velocities

RadVel models Keplerian orbits in radial velocity (RV) time series. The code is written in Python with a fast Kepler's equation solver written in C. It provides a framework for fitting RVs using maximum a posteriori optimization and computing robust confidence intervals by sampling the posterior probability density via Markov Chain Monte Carlo (MCMC). RadVel can perform Bayesian model comparison and produces publication quality plots and LaTeX tables.

[ascl:1902.008]
Radynversion: Solar atmospheric properties during a solar flare

Radynversion infers solar atmospheric properties during a solar flare. The code is based on an Invertible Neural Network (INN) that is trained to learn an approximate bijective mapping between the atmospheric properties of electron density, temperature, and bulk velocity (all as a function of altitude), and the observed Hα and Ca II λ8542 line profiles. As information is lost in the forward process of radiation transfer, this information is injected back into the model during the inverse process by means of a latent space; the training allows this latent space to be filled using an n-dimensional unit Gaussian distribution, where n is the dimensionality of the latent space. The code is based on a model trained by simulations made by RADYN, a 1D non-equilibrium radiation hydrodynamic model with good optically thick radiation treatment that does not consider magnetic effects.

[ascl:1411.010]
Raga: Monte Carlo simulations of gravitational dynamics of non-spherical stellar systems

Raga (Relaxation in Any Geometry) is a Monte Carlo simulation method for gravitational dynamics of non-spherical stellar systems. It is based on the SMILE software (ascl:1308.001) for orbit analysis. It can simulate stellar systems with a much smaller number of particles N than the number of stars in the actual system, represent an arbitrary non-spherical potential with a basis-set or spline spherical-harmonic expansion with the coefficients of expansion computed from particle trajectories, and compute particle trajectories independently and in parallel using a high-accuracy adaptive-timestep integrator. Raga can also model two-body relaxation by local (position-dependent) velocity diffusion coefficients (as in Spitzer's Monte Carlo formulation) and adjust the magnitude of relaxation to the actual number of stars in the target system, and model the effect of a central massive black hole.

[ascl:2312.019]
Rainbow: Simultaneous multi-band light curve fitting

Russeil, E.; Malanchev, K. L.; Aleo, P. D.; Ishida, E. E. O.; Pruzhinskaya, M. V.; Gangler, E.; Lavrukhina, A. D.; Volnova, A. A.; Voloshina, A.; Semenikhin, T.; Sreejith, S.; Kornilov, M. V.; Korolev, V. S.

Rainbow is a black-body parametric model for transient light curves. It uses Bazin function as a model for bolometric flux evolution and a logistic function for the temperature evolution; it provides seven fit parameters and goodness of fit (reduced χ^{2}) and is well-suited for transient objects. Also included is RainbowRisingFit, suitable for rising transient objects, which offers six fit parameters. It is based on a rising sigmoid bolometric flux and a sigmoid temperature evolution. These implementations are implemented in the light-curve processing toolbox (ascl:2107.001) for Python.

[ascl:2103.016]
RAiSERed: Analytic AGN model based code for radio-frequency redshifts

The RAiSERed (Radio AGN in Semi-analytic Environments: Redshifts) code implements the RAiSE analytic model for Fanaroff-Riley type II sources, using a Bayesian prior for their host cosmological environments, to measure the redshift of active galactic nuclei lobes based on radio-frequency observations. The Python code provides a class for the user to store measured attributes for each radio source, and to which model derived redshift probability density functions are returned. Systematic uncertainties in the analytic model can be calibrated by specifying a subset of radio sources with spectroscopic redshifts. Functions are additionally provided to plot the redshift probability density functions and assess the success of the model calibration.

[ascl:2302.022]
RALF: RADEX Line Fitter

The RADEX Line Fitter provides a Python 3 interface that calls RADEX (ascl:1010.075) to make a non-LTE fit to a set of observed lines and derive the column density of the molecule that produced the lines and optionally also the molecular hydrogen (H_{2}) number density or the kinetic temperature of the molecule. This code requires RADEX to be installed locally.

[ascl:1710.013]
Ramses-GPU: Second order MUSCL-Handcock finite volume fluid solver

RamsesGPU is a reimplementation of RAMSES (ascl:1011.007) which drops the adaptive mesh refinement (AMR) features to optimize 3D uniform grid algorithms for modern graphics processor units (GPU) to provide an efficient software package for astrophysics applications that do not need AMR features but do require a very large number of integration time steps. RamsesGPU provides an very efficient C++/CUDA/MPI software implementation of a second order MUSCL-Handcock finite volume fluid solver for compressible hydrodynamics as a magnetohydrodynamics solver based on the constraint transport technique. Other useful modules includes static gravity, dissipative terms (viscosity, resistivity), and forcing source term for turbulence studies, and special care was taken to enhance parallel input/output performance by using state-of-the-art libraries such as HDF5 and parallel-netcdf.

[ascl:1011.007]
RAMSES: A new N-body and hydrodynamical code

A new N-body and hydrodynamical code, called RAMSES, is presented. It has been designed to study structure formation in the universe with high spatial resolution. The code is based on Adaptive Mesh Refinement (AMR) technique, with a tree based data structure allowing recursive grid refinements on a cell-by-cell basis. The N-body solver is very similar to the one developed for the ART code (Kravtsov et al. 97), with minor differences in the exact implementation. The hydrodynamical solver is based on a second-order Godunov method, a modern shock-capturing scheme known to compute accurately the thermal history of the fluid component. The accuracy of the code is carefully estimated using various test cases, from pure gas dynamical tests to cosmological ones. The specific refinement strategy used in cosmological simulations is described, and potential spurious effects associated to shock waves propagation in the resulting AMR grid are discussed and found to be negligible. Results obtained in a large N-body and hydrodynamical simulation of structure formation in a low density LCDM universe are finally reported, with 256^3 particles and 4.1 10^7 cells in the AMR grid, reaching a formal resolution of 8192^3. A convergence analysis of different quantities, such as dark matter density power spectrum, gas pressure power spectrum and individual haloes temperature profiles, shows that numerical results are converging down to the actual resolution limit of the code, and are well reproduced by recent analytical predictions in the framework of the halo model.

[ascl:2008.021]
ramses2hsim: RAMSES output to 3D data cube for HSIM

Richardson, Mark L. A.; Routledge, L.; Thatte, N.; Tecza, M.; Houghton, Ryan C. W.; Pereira-Santaella, M.; Rigopoulou, D

The ramses2hsim pipeline converts a simulated galaxy in a RAMSES (ascl:1011.007) output into an 3D input data cube for HSIM (ascl:1912.006). The code incorporates gas kinematics (both bulk and turbulence), line emission and line width for Hα, and accounts for dust extinction.

[ascl:2105.019]
RandomQuintessence: Integrate the Klein-Gordon and Friedmann equations with random initial conditions

RandomQuintessence integrates the Klein-Gordon and Friedmann equations for quintessence models with random initial conditions and functional forms for the potential. Quintessence models generically impose non-trivial structure on observables like the equation of state of dark energy. There are three main modules; montecarlo_nompi.py sets initial conditions, loops over a bunch of randomly-initialised models, integrates the equations, and then analyses and saves the resulting solutions for each model. Models are defined in potentials.py; each model corresponds to an object that defines the functional form of the potential, various model parameters, and functions to randomly draw those parameters. All of the equation-solving code and methods to analyze the solution are kept in solve.py under the base class DEModel(). Other files available analyze and plot the data in a variety of ways.

[ascl:2003.007]
RAPID: Real-time Automated Photometric IDentification

RAPID (Real-time Automated Photometric IDentification) classifies multiband photometric light curves into several different transient classes. It uses a deep recurrent neural network to produce time-varying classifications, and because it does not rely on deriving computationally expensive features from the data, it is well suited for processing alerts that wide-field surveys such as the Zwicky Transient Facility (ZTF) and the Large Synoptic Survey Telescope (LSST) will produce.

[ascl:2209.016]
RAPOC: Rosseland and Planck mean opacities calculator

RAPOC (Rosseland and Planck Opacity Converter) uses molecular absorption measurements (*i.e.*, wavelength-dependent opacities) for a given temperature, pressure, and wavelength range to calculate Rosseland and Planck mean opacities for use in atmospheric modeling. The code interpolates between discrete data points and can use ExoMol and DACE data, or any user-defined data provided in a readable format. RAPOC is simple, straightforward, and easily incorporated into other codes.

[ascl:2005.016]
RAPP: Robust Automated Photometry Pipeline

RAPP is a robust automated photometry pipeline for blurred images. RAPP requires that the observed images contain at least three stars and applies bias, dark, and flat field correction on blurred observational raw data; it also uses the median of adjacent pixels to eliminate outliers. It also uses star enhancement and robust image matching, extracts stars, and performs aperture photometry to extract information from blurred images.

[ascl:2308.008]
Rapster: Rapid population synthesis for binary black hole mergers in dynamical environments

Rapster (RAPid cluSTER evolution) models binary black hole population synthesis and the evolution of star clusters based on simple, yet realistic prescriptions. The code can generate large populations of dynamically formed binary black holes. Rapster uses SEVN (ascl:2206.019) to model the initial black hole mass spectrum and PRECESSION (ascl:1611.004) to model the mass, spin, and gravitational recoil of merger remnants.

[ascl:1803.015]
RAPTOR: Imaging code for relativistic plasmas in strong gravity

Bronzwaer, Thomas; Davelaar, Jordy; Younsi, Ziri; Mościbrodzka, Monika; Falcke, Heino; Kramer, Michael; Rezzolla, Luciano

RAPTOR produces accurate images, animations, and spectra of relativistic plasmas in strong gravity by numerically integrating the equations of motion of light rays and performing time-dependent radiative transfer calculations along the rays. The code is compatible with any analytical or numerical spacetime, is hardware-agnostic and may be compiled and run on both GPUs and CPUs. RAPTOR is useful for studying accretion models of supermassive black holes, performing time-dependent radiative transfer through general relativistic magneto-hydrodynamical (GRMHD) simulations and investigating the expected observational differences between the so-called fastlight and slow-light paradigms.

[ascl:1909.008]
RascalC: Fast code for galaxy covariance matrix estimation

RascalC quickly estimates covariance matrices from two- or three-point galaxy correlation functions. Given an input set of random particle locations and a two-point correlation function (or input set of galaxy positions), RascalC produces an estimate of the associated covariance for a given binning strategy, with non-Gaussianities approximated by a ‘shot-noise-rescaling’ parameter. For the 2PCF, the rescaling parameter can be calibrated by dividing the particles into jackknife regions and comparing sample to theoretical jackknife covariance. RascalC can also be used to compute Legendre-binned covariances and cross-covariances between different two-point correlation functions.

[ascl:2002.002]
RASCAS: Resonant line transfer in AMR simulations

Michel-Dansac, Leo; Blaizot, Jeremy; Garel, Thibault; Verhamme, Anne; Kimm, Taysun; Trebitsch, Maxime

The massively parallel code RASCAS (RAdiative SCattering in Astrophysical Simulations) performs radiative transfer on an adaptive mesh with an octree structure using the Monte Carlo technique. The code features full MPI parallelization, domain decomposition, adaptive load-balancing, and a standard peeling algorithm to construct mock observations. The radiative transport of resonant line photons through different mixes of species (e.g. HI, SiII, MgII, FeII), including their interaction with dust, is implemented in a modular fashion to allow new transitions to be easily added to the code. RASCAS may also be used to propagate photons at any wavelength (e.g. stellar continuum or fluorescent lines), and has been designed to be easily customizable and to process simulations of arbitrarily large sizes on large supercomputers.

[ascl:2102.022]
RASSINE: Normalizing 1D stellar spectra

RASSINE normalizes merged 1D spectra using the concept of convex hulls. The code uses six parameters that can be fine-tuned, and provides an interactive interface, including graphical feedback, for easily choosing the parameters. RASSINE can also provide a first guess for the parameters that are derived directly from the merged 1D spectrum based on previously performed calibrations.

[ascl:1904.014]
rate: Reliable Analytic Thermochemical Equilibrium

rate computes thermochemical-equilibrium abundances for a H-C-N-O system with known pressure, temperature, and elemental abundances. The output abundances are H2O, CH4, CO, CO2, NH3, C2H2, C2H4, HCN, and N2, H2, H, and He.

[ascl:0008.002]
RATRAN: Radiative Transfer and Molecular Excitation in One and Two Dimensions

RATRAN is a numerical method and computer code to calculate the radiative transfer and excitation of molecular lines. The approach is based on the Monte Carlo method, and incorporates elements from Accelerated Lambda Iteration. It combines the flexibility of the former with the speed and accuracy of the latter. Convergence problems known to plague Monte Carlo methods at large optical depth (>100) are avoided by separating local contributions to the radiation field from the overall transfer problem. The random nature of the Monte Carlo method serves to verify the independence of the solution to the angular, spatial, and frequency sampling of the radiation field. This allows the method to be used in a wide variety of astrophysical problems without specific adaptations. Moreover, the code can be applied to all atoms or molecules for which collisional rate coefficients are available and any axially symmetric source model. Continuum emission and absorption by dust is explicitly taken into account but scattering is neglected. We expect this program to be an important tool in analyzing data from present and future infrared and (sub-)millimeter telescopes.

[ascl:1105.009]
Ray Tracing Codes: run_tau, run_raypath, and ray_kernel

Time-distance helioseismology aims to measure and interpret the travel times of waves propagating between two points located on the solar surface. The travel times are then inverted to infer sub-surface properties that are encoded in the measurements. The trajectory of the waves generally follows that of the infinite-frequency ray path, although they are sensitive to perturbations off of this path. Finite-frequency sensitivity kernels are thus needed to give more accurate inversion results.

Ray tracing codes calculate travel time kernels for a ray. There are three main codes which calculate the group time as a function of distance, the ray paths as well as the phase and group times along the path, and the ray kernels for the sound speed squared.

[ascl:2401.002]
Rayleigh: Pseudo-spectral MHD

Featherstone, Nicholas A.; Edelmann, Philipp V. F.; Gassmoeller, Rene; Matilsky, Loren I.; Orvedahl, Ryan J.; Wilson, Cian R.

The 3-D convection code Rayleigh enables study of dynamo behavior in spherical geometry. It evolves the incompressible and anelastic MHD equations in spherical geometry using a pseudo-spectral approach. Rayleigh employs spherical harmonics in the horizontal direction and Chebyshev polynomials in the radial direction and has undergone extensive accuracy testing.

[ascl:1411.006]
RC3 mosaicking pipeline: Creating mosaics for the RC3 Catalogue

The RC3 mosaicking pipeline creates color composite images and scientifically-calibrated FITS mosaics in all SDSS imaging bands for all the RC3 galaxies that lie within the survey’s footprint and on photographic plates taken by the Digitized Palomar Observatory Sky Survey (DPOSS) for the B, R, IR bands. The pipeline uses SExtractor (ascl:1010.064) for extraction and STIFF (ascl:1110.006) to generating color images. The mosaicking program uses a recursive algorithm for positional update first to correct the positional inaccuracy inherent in the RC3 catalog, then conducts the mosaicking procedure using the Astropy (ascl:1304.002) wrapper to IPAC's Montage (ascl:1010.036) software. The program is generalized into a pipeline that can be easily extended to future survey data or other source catalogs; an online interface is available at

http://lcdm.astro.illinois.edu/data/rc3/search.html.

[submitted]
RCETC: Roman Coronagraph Exposure Time Calculator

Hildebrandt, S.R.; Spohn, C.; Nemati, B.; Savransky, D.; Bailey, V.; Debes, J.; Douglas, E.S.; Keithly, D.; Kern, B.; Sheldon, L.J.

The Roman Coronagraph Exposure Time Calculator (Roman_Coronagraph_ETC for short) is the public version of the exposure time calculator of the Coronagraph Instrument aboard the Nancy Grace Roman Space Telescope funded by NASA. The methods used to estimate the integration times are based upon peer reviewed research articles (see Bibliography) and a collection of instrumental and modeling parameters of both the Coronagraph Instrument and the Nancy Grace Roman Space Telescope. The code is written in python. Visit https://github.com/hsergi/Roman_Coronagraph_ETC for more information.

[ascl:2009.015]
rcosmo: Cosmic Microwave Background data analysis

rcosmo provides information processing, visualization, manipulation and spatial statistical analysis of Cosmic Microwave Background (CMB) radiation and other spherical data stored in or converted to HEALPix coordinates. The package has more than 100 different functions, and can perform spherical geometry, manipulate CMB and other spherical data, and visualize HEALPix data. rcosmo can also perform statistical analysis of CMB and spherical data, and transforme spherical data in cartesian and geographic coordinates into HEALPix format.

[ascl:2302.006]
RCR: Robust Chauvenet Outlier Rejection

RCR provides advanced outlier rejection that is easy to use. Both sigma clipping, the simplest form of outlier rejection, and traditional Chauvenet rejection make use of non-robust quantities, the mean and standard deviation, which are sensitive to the outliers that they are being used to reject. This limits such techniques to samples with small contaminants or small contamination fractions. RCR instead first makes use of robust replacements for the mean, such as the median and the half-sample mode, and similar robust replacements for the standard deviation. RCR has been carefully calibrated and can be applied to samples with both large contaminants and large contaminant fractions (sometimes in excess of 90% contaminated).

[ascl:1408.017]
RDGEN: Routines for data handling, display, and adjusting

RDGEN is a collection of routines for data handling, display, and adjusting, with a facility which helps to set up files for using with VPFIT (ascl:1408.015); it is included in the VPFIT distribution file. It is useful for setting region boundaries and initial guesses for VPFIT, for displaying the accumulated results, for examining by eye particular redshift systems and fits to them, testing that the error array is a true reflection of the rms scatter in the data, comparing spectra and generally examining and even modifying the data.

[ascl:2301.017]
ReACT: Calculation of non-linear power spectra from non-standard physics

ReACT extends the Copter (ascl:1304.022) and MG-Copter packages, which calculate redshift and real space large scale structure observables for a wide class of gravity and dark energy models. Additions to Copter include spherical collapse in modified gravity, halo model power spectrum for general theories, and real and redshift space LSS 2 point statistics for modified gravity and dark energy. ReACT also includes numerical perturbation theory kernel solvers, real space bispectra in modified gravity, and a numerical perturbation theory kernel solver up to 4th order for 1-loop bispectrum.

[ascl:2007.016]
ReadPDS: Visualization tools for PDS4 data

ReadPDS reads in and visualizes data from the Planetary Data System in PDS4 format. Tools are available in Python as PDS4Viewer and in IDL as PDS4-IDL. These tools support PDS4 data, including images, spectra, and arrays and provide multiple views of the data, including summary, image, plot, and table views in addition to easy access to metadata such as structure labels and spectral characteristics.

[ascl:1506.007]
REALMAF: Magnetic power spectra from Faraday rotation maps

REALMAF is a maximum-a-posteriori code to measure magnetic power spectra from Faraday rotation data. It uses a sophisticated model for the magnetic autocorrelation in real space, thus alleviating the need for simplifying assumptions in the processing. REALMAF treats the divergence relation of the magnetic field with a multiplicative factor in Fourier space, which allows modeling the magnetic autocorrelation as a spherically symmetric function.

[ascl:2206.022]
RealSim-IFS: Realistic synthetic integral field spectrscopy of galaxies from numerical simulations

RealSim-IFS generates survey-realistic integral-field spectroscopy (IFS) observations of galaxies from numerical simulations of galaxy formation. The tool is designed primarily to emulate current and experimental observing strategies for IFS galaxy surveys in astronomy, and can reproduce both the flux and variance propagation of real galaxy spectra to cubes. RealSim-IFS has built-in functions supporting SAMI and MaNGA IFU footprints, but supports any fiber-based IFU design, in general.

[ascl:1107.009]
REAS3: Modeling Radio Emission from Cosmic Ray Air Showers

The freely available Monte Carlo code REAS for modelling radio emission from cosmic ray air showers has evolved to include the full complexity of air shower physics. REAS3 improves the calculation of the emission contributions, which was not fully consistent in earlier versions of REAS, by incorporating the missing radio emission due to the variation of the number of charged particles during the air shower evolution using an "end-point formalism". With the inclusion of these emission contributions, the structure of the simulated radio pulses changes from unipolar to bipolar, and the azimuthal emission pattern becomes nearly symmetric. Remaining asymmetries can be explained by radio emission due to the variation of the net charge excess in air showers, which is automatically taken into account in the new implementation. REAS3 constitutes the first self-consistent time-domain implementation based on single particle emission taking the full complexity of air shower physics into account, and is freely available for all interested users. REAS3 has been superseded by CoREAS (ascl:1406.003).

[ascl:1110.016]
REBOUND: Multi-purpose N-body code for collisional dynamics

REBOUND is a multi-purpose N-body code which is freely available under an open-source license. It was designed for collisional dynamics such as planetary rings but can also solve the classical N-body problem. It is highly modular and can be customized easily to work on a wide variety of different problems in astrophysics and beyond.

REBOUND comes with symplectic integrators WHFast, WHFastHelio, SEI, and LEAPFROG. It supports open, periodic and shearing-sheet boundary conditions. REBOUND can use a Barnes-Hut tree to calculate both self-gravity and collisions. These modules are fully parallelized with MPI as well as OpenMP. The former makes use of a static domain decomposition and a distributed essential tree. Two new collision detection modules based on a plane-sweep algorithm are also implemented. The performance of the plane-sweep algorithm is superior to a tree code for simulations in which one dimension is much longer than the other two and in simulations which are quasi-two dimensional with less than one million particles.

[ascl:2011.020]
REBOUNDx: Adding effects in REBOUND N-body integrations

REBOUNDx incorporates additional physics into REBOUND (ascl:1110.016) simulations. Users can add effects from a list of pre-implemented astrophysical forces or contribute new ones. The main code is written in C, and a Python wrapper is provided for interfacing with other libraries. The REBOUNDx source code is machine independent and a binary format to save REBOUNDx configurations interfaces with the SimulationArchive class in REBOUND, making it possible to share and reproduce results bit by bit.

[ascl:1106.026]
RECFAST: Calculate the Recombination History of the Universe

RECFAST calculates the recombination of H, HeI, and HeII in the early Universe; this involves a line-by-line treatment of each atomic level. It differs in comparison to previous calculations in two major ways: firstly, the ionization fraction x_e is approximately 10% smaller for redshifts <~800, due to non-equilibrium processes in the excited states of H, and secondly, HeI recombination is much slower than previously thought, and is delayed until just before H recombines. RECFAST enables fast computation of the ionization history (and quantities such as the power spectrum of CMB anisotropies which depend on it) for arbitrary cosmologies.

[ascl:2005.004]
REDFIT: Red-noise spectra directly from unevenly spaced time series

Time series are commonly unevenly spaced in time make it difficult to obtain an accurate estimate of their typical red-noise spectrum. REDFIT overcomes this problem by fitting a first-order autoregressive (AR1) process directly to unevenly spaced time series. Hence, interpolation in the time domain and its inevitable bias can be avoided. The program can be used to test if peaks in the spectrum of a time series are significant against the red-noise background from an AR1 process.

[ascl:2106.024]
RedPipe: Reduction Pipeline

The RedPipe collection of Python scripts performs optical photometric and spectroscopic data reduction. There are scripts on preprocessing, photometry, calibration, spectroscopy, analysis and plotting. The photometry and spectroscopy codes use pyraf (ascl:1207.011) and hence require an already existing installation of Image Reduction and Analysis Facility (IRAF, ascl:9911.002).

[ascl:2103.004]
redshifts: Spectroscopic redshifts search tool

redshifts collects all unique spectroscopic redshifts from online databases such as VizieR and NED. It can perform a flexible search within a radius of a given set of (RA, DEC) coordinates and uses column names and descriptions (including UCD keywords) to identify columns containing spectroscopic redshifts or velocities. It weeds out photometric redshifts and duplicates and returns a unique list of best spectroscopic redshift measurements. redshifts can be used standalone from the terminal, and can take a number of optional command line arguments, or from Python.

[ascl:1507.017]
REDSPEC: NIRSPEC data reduction

REDSPEC is an IDL based reduction package designed with NIRSPEC in mind though can be used to reduce data from other spectrographs as well. REDSPEC accomplishes spatial rectification by summing an *A+B* pair of a calibration star to produce an image with two spectra; the image is remapped on the basis of polynomial fits to the spectral traces and calculation of gaussian centroids to define their separation, producing straight spectral traces with respect to the detector rows. The raw images are remapped onto a coordinate system with uniform intervals in spatial extent along the slit and in wavelength along the dispersion axis.

[ascl:1508.003]
REDUCEME: Long-slit spectroscopic data reduction and analysis

Cardiel, N; Gorgas, J.; Pedraz, S.; Cenarro, J.; Alonso, O; Gil de Paz, A.; García-Dabó, E.; Sánchez-Blázquez, P.; Mármol-Queraltó, E.; Toloba, E.

The astronomical data reduction package REDUCEME reduces and analyzes long-slit spectroscopic data. The package uses the unformatted FORTRAN raw data format, so requires FITS files be transformed to REDUCEME format; the reverse operation (from REDUCEME to FITS format) is also available. The package is a set of programs written in FORTRAN 77 and includes shell scripts (using the C shell syntax) to perform routine tasks; it can be extended by the inclusion of external programs. REDUCEME uses PGPLOT (ascl:1103.002) for line plots and images, and a subset of subroutines, called BUTTON, enables the user to communicate interactively with the image display employing graphic buttons. One advantage of using REDUCEME is that for each image an associated error image can also be processed throughout the reduction process, allowing for a careful control of the error propagation.

[ascl:2106.017]
redvsblue: Quasar and emission line redshift fitting

redvsblue measures a precise redshift given a broad redshift prior. For each emission line or the full spectrum, the software runs a coarse chi2 scan as a function of redshift, using the input PCA+broadband Legendre polynomials, and finds three local minima, and does a finer chi2 scan in each minima. It then defines the global PCA redshift (ZPCA) from the best minimum of the three; ZPCA is a redshift estimator biased toward the computation of the PCA. The redshift of the line (ZLINE) is defined from the maximum of the best-fit model of the line. ZLINE is a redshift estimator un-biased toward the velocity of the line, but can be biased with respect to the cosmological redshift. The output is a FITS file, with one HDU per redshift type.

[ascl:1401.004]
Reflex: Graphical workflow engine for data reduction

Reflex provides an easy and flexible way to reduce VLT/VLTI science data using the ESO pipelines. It allows graphically specifying the sequence in which the data reduction steps are executed, including conditional stops, loops and conditional branches. It eases inspection of the intermediate and final data products and allows repetition of selected processing steps to optimize the data reduction. The data organization necessary to reduce the data is built into the system and is fully automatic; advanced users can plug their own modules and steps into the data reduction sequence. Reflex supports the development of data reduction workflows based on the ESO Common Pipeline Library. Reflex is based on the concept of a scientific workflow, whereby the data reduction cascade is rendered graphically and data seamlessly flow from one processing step to the next. It is distributed with a number of complete test datasets so users can immediately start experimenting and familiarize themselves with the system.

[ascl:1206.001]
RegiStax: Alignment, stacking and processing of images

Berrevoets, Cor; DeClerq, Bart; George, Tony; Makolkin, Dmitry; Maxson, Paul; Pilz, Bob; Presnyakov, Pavel; Roel, Eric; Weiller, Sylvain

RegiStax is software for alignment/stacking/processing of images; it was released over 10 years ago and continues to be developed and improved. The current version is RegiStax 6, which supports the following formats: AVI, SER, RFL (RegiStax Framelist), BMP, JPG, TIF, and FIT. This version has a shorter and simpler processing sequence than its predecessor, and optimizing isn't necessary anymore as a new image alignment method optimizes directly. The interface of RegiStax 6 has been simplified to look more uniform in appearance and functionality, and RegiStax 6 now uses Multi-core processing, allowing the user to have up to have multiple cores(recommended to use maximally 4) working simultaneous during alignment/stacking.

[ascl:1404.012]
RegPT: Regularized cosmological power spectrum

RegPT computes the power spectrum in flat wCDM class models based on the RegPT treatment when provided with either of transfer function or matter power spectrum. It then gives the multiple-redshift outputs for power spectrum, and optionally provides correlation function data. The Fortran code has two major options for power spectrum calculations; -fast, which quickly computes the power spectrum at two-loop level (typically a few seconds) using the pre-computed data set of PT kernels for fiducial cosmological models, and -direct, in which the code first applies the fast method, and then follows the regularized expression for power spectrum to directly evaluate the multi-dimensional integrals. The output results are the power spectrum of direct calculation and difference of the results between fast and direct method. The code also gives the data set of PT diagrams necessary for power spectrum calculations from which the power spectrum can be constructed.

[ascl:2107.005]
ReionYuga: Epoch of Reionization neutral Hydrogen field generator

The C code ReionYuga generates the Epoch of Reionization (EoR) neutral Hydrogen (HI) field (successively the redshifted 21-cm signal) within a cosmological simulation box using semi-numerical techniques. The code is based on excursion set formalism and uses a three parameter model. It is designed to work with PMN-body (ascl:2107.003) and FoF-Halo-finder (ascl:2107.004).

[ascl:2306.023]
RELAGN: AGN SEDs with full GR ray tracing

RELAGN creates spectral models for the calculation of AGN SEDs, ranging from the Optical/UV (outer accretion disc) to the Hard X-ray (Innermost X-ray Corona). The code is available in two languages, Python and Fortran. The Fortran version is written to be used with the spectral fitting software XSPEC (ascl:9910.005), and is the preferred version for analyzing X-ray spectral data. The Python version provides more flexibility for modeling. Whereas the Fortran version produces only a spectrum, the Python implementation can extract the physical properties of the system (such as the physical mass accretion rate, disc size, and efficiency parameters) since these are all stored as attributes within the model. Both versions require a working installation of HEASOFT (ascl:1408.004).

[ascl:2307.003]
RelicFast: Fast scale-dependent halo bias

RelicFast computes the scale-dependent bias induced by relics of different masses, spins, and temperatures, through spherical collapse and the peak-background split. The code determines halo bias in under a second, making it possible to include this effect for different cosmologies, and light relics, at little computational cost.

[ascl:1505.021]
relline: Relativistic line profiles calculation

relline calculates relativistic line profiles; it is compatible with the common X-ray data analysis software XSPEC (ascl:9910.005) and ISIS (ascl:1302.002). The two basic forms are an additive line model (RELLINE) and a convolution model to calculate relativistic smearing (RELCONV).

[ascl:2010.015]
relxill: Reflection models of black hole accretion disks

Dauser, T.; García, J.; Parker, M. L.; Fabian, A. C.; Wilms, J.; Lohfink, A.; Kallman, T. R.; Steiner, J. F.; McClintock, J. E.; Brenneman, L.; Eikmann, W.; Reynolds, C. S.; Tombesi, F.

relxill self-consistently connects an angle-dependent reflection model constructed with XILLVER (http://www.srl.caltech.edu/personnel/javier/xillver/index.html) with the relativistic blurring code RELLINE (ascl:1505.021). It calculates the proper emission angle of the radiation at each point on the accretion disk and then takes the corresponding reflection spectrum into account.

[ascl:2307.049]
reMASTERed: Calculate contributions to pseudo-Cl for maps with correlated masks

reMASTERed reconstructs ensemble-averaged pseudo-$C_\ell$ to effectively exact precision, with significant improvements over traditional estimators for cases where the map and mask are correlated. The code can compute the results given an arbitrary map and mask; it can also compute the results in the ensemble average for certain types of threshold masks.

[ascl:1904.008]
repack: Repack and compress line-transition data

repack re-packs and compresses line-transition data for radiative-transfer calculations. It identifies the strong lines that dominate the spectrum from the large-majority of weaker lines, returning a binary line-by-line (LBL) file with the strong lines info (wavenumber, Elow, gf, and isotope ID), and an ASCII file with the combined contribution of the weaker lines compressed into a continuum extinction coefficient (in cm-1 amagat-1) as function of wavenumber and temperature.

[ascl:2107.021]
RePrimAnd: Recovery of Primitives And EOS framework

The RePrimAnd library supports numerical simulations of general relativistic magnetohydrodynamics. It provides methods for recovering primitive variables such as pressure and velocity from the variables evolved in quasi-conservative formulations. Further, it provides a general framework for handling matter equations of state (EOS). Python bindings are automatically built together with the library, provided a Python3 installation containing the pybind11 package is detected. RePrimAnd also provides an (experimental) thorn that builds the library within an Einstein Toolkit (ascl:1102.014) environment using the ExternalLibraries mechanism.

[ascl:2011.023]
reproject: Python-based astronomical image reprojection

reproject implements image reprojection (resampling) methods for astronomical images using various techniques via a uniform interface. Reprojection re-grids images from one world coordinate system to another (for example changing the pixel resolution, orientation, coordinate system). reproject works on celestial images by interpolation, as well as by finding the exact overlap between pixels on the celestial sphere. It can also reproject to/from HEALPIX projections by relying on the astropy-healpix package.

[ascl:1612.022]
REPS: REscaled Power Spectra for initial conditions with massive neutrinos

Zennaro, Matteo; Bel, Julien; Villaescusa-Navarro, Francisco; Carbone, Carmelita; Sefusatti, Emiliano; Guzzo, Luigi

REPS (REscaled Power Spectra) provides accurate, one-percent level, numerical simulations of the initial conditions for massive neutrino cosmologies, rescaling the late-time linear power spectra to the simulation initial redshift.

[ascl:1809.016]
RequiSim: Variance weighted overlap calculator

RequiSim computes the Variance Weighted Overlap, which is a measure of the bias on the lensing signal from power spectrum modelling bias for any non-linear model. It assumes that the bias on the power spectrum is Gaussian with a covariance described by a user-provided knowledge matrix that describes the covariance in the bias on the power spectrum. The data from the Euclid wide-field survey are included.

[ascl:1505.028]
RESOLVE: Bayesian algorithm for aperture synthesis imaging in radio astronomy

RESOLVE is a Bayesian inference algorithm for image reconstruction in radio interferometry. It is optimized for extended and diffuse sources. Features include parameter-free Bayesian reconstruction of radio continuum data with a focus on extended and weak diffuse sources, reconstruction with uncertainty propagation dependent on measurement noise, and estimation of the spatial correlation structure of the radio astronomical source. RESOLVE provides full support for measurement sets and includes a simulation tool (if uv-coverage is provided).

[ascl:1907.023]
REVOLVER: REal-space VOid Locations from suVEy Reconstruction

REVOLVER reconstructs real space positions from redshift-space tracer data by subtracting RSD through FFT-based reconstruction (optional) and applies void-finding algorithms to create a catalogue of voids in these tracers. The tracers are normally galaxies from a redshift survey but could also be halos or dark matter particles from a simulation box. Two void-finding routines are provided. The first is based on ZOBOV (ascl:1304.005) and uses Voronoi tessellation of the tracer field to estimate the local density, followed by a watershed void-finding step. The second is a voxel-based method, which uses a particle-mesh interpolation to estimate the tracer density, and then uses a similar watershed algorithm. Input data files can be in FITS format, or ASCII- or NPY-formatted data arrays.

[ascl:2306.028]
rfast: Planetary spectral forward and inverse modeling tool

rfast ingests tables of opacities and generates synthetic spectra of worlds and retrieves real or simulated spectral observations. It can add noise, perform inverse modeling, and plot results. The tool can be applied to simulated and real observations spanning reflected-light, thermal emission, and transit transmission. Retrieval parameters can be toggled and parameters can be retrieved in log or linear space and adopt a Gaussian or flat prior.

[ascl:2005.018]
RFCDE: Random Forests for Conditional Density Estimation

RFCDE provides an implementation of random forests designed for conditional density estimation. It computes a kernel density estimate of y with nearest neighbor weightings defined by the location of the evaluation point x relative to the leaves in the random forest.

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