Results 1201-1250 of 3560 (3466 ASCL, 94 submitted)

[ascl:1507.009]
PPInteractions: Secondary particle spectra from proton-proton interactions

PPInteractions generates the secondary particle energy spectra produced in proton-proton interactions over the entire chosen energy range for any value of the primary proton spectral index by adjusting the low energy part of the spectra (below 0.1TeV) to the high energy end of the spectra (above 0.1TeV). This code is based on the parametrization of Kelner et al (2006), in which the normalization of the low energy part of the spectra is given only for 3 values of the primary proton spectral indices (2, 2.5, 3).

[ascl:1401.009]
PPF module for CAMB

The main CAMB code supports smooth dark energy models with constant equation of state and sound speed of one, or a quintessence model based on a potential. This modified code generalizes it to support a time-dependent equation of state w(a) that is allowed to cross the phantom divide, i.e. w=-1 multiple times by implementing a Parameterized Post-Friedmann(PPF) prescription for the dark energy perturbations.

[ascl:2212.017]
powspec: Power and cross spectral density of 2D arrays

powspec provides functions to compute power and cross spectral density of 2D arrays. Units are properly taken into account. It can, for example, create fake Gaussian field images, compute power spectra P(k) of each image, shrink a mask with regard to a kernel, generate a Gaussian field, and plot various results.

[ascl:2301.023]
PoWR: Potsdam Wolf-Rayet Models

Hamann, W. R.; Gräfener, G.; Koesterke, L.; Sander, A.; Shenar, T.; Hainich, R.; Gímenez-García, A.; Todt, H.

PoWR (Potsdam Wolf-Rayet Models) calculates synthetic spectra for Wolf-Rayet and OB stars from model atmospheres which account for Non-LTE, spherical expansion and metal line blanketing. The model data is provided through a web interface and includes Spectral Energy Distribution, line spectrum in high resolution for different wavelength bands, and atmosphere stratification. For Wolf-Rayet stars of the nitrogen subclass, there are grids of hydrogen-free models and of models with a specified mass fraction of hydrogen. The iron-group and total CNO mass fractions correspond to the metallicity of the Galaxy, the Large Magellanic Cloud, or the Small Magellanic Cloud, respectively. The source code is available as a tarball on the same web interface.

[ascl:1110.017]
POWMES: Measuring the Power Spectrum in an N-body Simulation

POWMES is a F90 program to measure very accurately the power spectrum in a N-body simulation, using Taylor expansion of some order on the cosine and sine transforms. It can read GADGET format and requires FFTW2 to be installed.

[ascl:2406.025]
PowerSpecCovFFT: FFTLog-based computation of non-Gaussian analytic covariance of galaxy power spectrum multipoles

PowerSpecCovFFT computes the non-Gaussian (regular trispectrum and its shot noise) part of the analytic covariance matrix of the redshift-space galaxy power spectrum multipoles using an FFTLog-based method. The galaxy trispectrum is based on a tree-level standard perturbation theory but with a slightly different galaxy bias expansion. The code computes the non-Gaussian covariance of the power spectrum monopole, quadrupole, hexadecapole, and their cross-covariance up to kmax ~ 0.4 h/Mpc.

[ascl:1805.001]
powerbox: Arbitrarily structured, arbitrary-dimension boxes and log-normal mocks

powerbox creates density grids (or boxes) with an arbitrary two-point distribution (i.e. power spectrum). The software works in any number of dimensions, creates Gaussian or Log-Normal fields, and measures power spectra of output fields to ensure consistency. The primary motivation for creating the code was the simple creation of log-normal mock galaxy distributions, but the methodology can be used for other applications.

[ascl:1807.021]
POWER: Python Open-source Waveform ExtractoR

POWER (Python Open-source Waveform ExtractoR) monitors the status and progress of numerical relativity simulations and post-processes the data products of these simulations to compute the gravitational wave strain at future null infinity.

[ascl:2006.018]
Powderday: Dust radiative transfer package

Narayanan, Desika; Turk, Matthew J.; Robitaille, Thomas; Kelly, Ashley J.; Connor McClellan, B.; Sharma, Ray S.; Garg, Prerak; Abruzzo, Matthew; Choi, Ena; Conroy, Charlie; Johnson, Benjamin D.; Kimock, Benjamin; Li, Qi; Lovell, Christopher C.; Lower, Sidney; Privon, George C.; Roberts, Jonathan; Sethuram, Snigdaa; Snyder, Gregory F.; Thompson, Robert; Wise, John H.

The dust radiative transfer software Powderday interfaces with galaxy formation simulations to produce spectral energy distributions and images. The code uses fsps (ascl:1010.043) and its Python bindings python-fsps for stellar SEDs, Hyperion (ascl:1207.004) for dust radiative transfer, and works with a variety of packages, including Arepo (ascl:1909.010), Changa (ascl:1105.005), Gasoline (ascl:1710.019), and Gizmo (ascl:1410.003); threaded throughout is yt (ascl:1011.022).

[ascl:2210.019]
POSYDON: Single and binary star population synthesis code

Fragos, Tassos; Andrews, Jeff J.; Bavera, Simone S.; Berry, Christopher P. L.; Coughlin, Scott; Dotter, Aaron; Giri, Prabin; Kalogera, Vicky; Katsaggelos, Aggelos; Kovlakas, Konstantinos; Lalvani, Shamal; Misra, Devina; Srivastava, Philipp M.; Qin, Ying; Rocha, Kyle A.; Roman-Garza, Jaime; Serra, Juan Gabriel; Stahle, Petter; Sun, Meng; Teng, Xu; Trajcevski, Goce; Hai Tran, Nam; Xing, Zepei; Zapartas, Emmanouil; Zevin, Michael

POSYDON (POpulation SYnthesis with Detailed binary-evolution simulatiONs) incorporates full stellar structure and evolution modeling for single and binary-star population synthesis. The code is modular and allows the user to specify initial population properties and adopt choices that determine how stellar evolution proceeds. Populations are simulated with the use of MESA (ascl:1010.083) evolutionary tracks for single, non-interacting, and interacting binaries organized in grids. Machine-learning methods are incorporated and applied on the grids for classification and various interpolation calculations, and the development of irregular grids guided by active learning, for computational efficiency.

[ascl:1411.021]
POSTMORTEM: Visibility data reduction and map making package

POSTMORTEM is the visibility data reduction and map making package from MRAO (Mullard Radio Astronomy Observatory) and is used with the Ryle and CLFST telescopes at Cambridge. It contains sub-systems for nonitoring telescope performance, displaying and editing the visibility data, performing calibrations, removing flux from interfering bright sources, and map-making. It requires PGPLOT (ascl:1103.002), SLALIB (ascl:1403.025), and NAG numerical routines, all of which are distributed with the STARLINK software collection (ascl:1110.012) or available separately.

[ascl:2104.031]
Posidonius: N-Body simulator for planetary and/or binary systems

Posidonius is a N-body code based on the tidal model used in Mercury-T (ascl:1511.020). It uses the REBOUND (ascl:1110.016) symplectic integrator WHFast to compute the evolution of positions and velocities, which is also combined with a midpoint integrator to calculate the spin evolution in a consistent way. As Mercury-T, Posidonius takes into account tidal forces, rotational-flattening effects and general relativity corrections. It also includes different evolution models for FGKML stars and gaseous planets. The N-Body code is written in Rust; a Python package is provided to easily define simulation cases in JSON format, which is readable by the Posidonius integrator.

[ascl:2003.006]
PORTAL: POlarized Radiative Transfer Adapted to Lines

PORTAL (POlarized Radiative Transfer Adapted to Lines), a 3D polarized radiative transfer code, simulates the emergence of polarization in the emission of atomic or molecular (sub-)millimeter lines. Written in Fortran90, PORTAL can be used in standalone mode or can process the output of other 3D radiative transfer codes

[ascl:2106.037]
PORTA: POlarized Radiative TrAnsfer

PORTA solves three-dimensional non-equilibrium radiative transfer problems with massively parallel computers. The code can be used for modeling the spectral line polarization produced by the scattering of anisotropic radiation and the Hanle and Zeeman effects assuming complete frequency redistribution, either using two-level or multilevel atomic models. The numerical method of solution used to find the self-consistent values of the atomic density matrix at each point of the model’s Cartesian grid is based on Jacobi iterative scheme and on a short-characteristics formal solver of the Stokes-vector transfer equation that uses monotonic Bézier interpolation. The code can also be used to compute the linear polarization of the continuum radiation caused by Rayleigh and Thomson scattering in 3D models of stellar atmospheres, and to solve the simpler 3D radiative transfer problem of unpolarized radiation in multilevel systems. PORTA accepts/produces HDF5 input/output and offers an advanced graphical user interface.

[ascl:2202.021]
popsynth: Observed surveys from latent population models

Popsynth provides an abstract way to generate survey populations from arbitrary luminosity functions and redshift distributions. Additionally, auxiliary quantities can be sampled and stored. Populations can be saved and restored via an HDF5 files for later use, and population synthesis routines can be created via classes or structured YAML files. Users can construct their own classes for spatial, luminosity, and other distributions, all of which can be connected to arbitrarily complex selection functions.

[ascl:1912.008]
PopSyCLE: Population Synthesis for Compact object Lensing Events

PopSyCLE performs compact object population synthesis while taking photometric and astrometric microlensing effects into consideration. It uses Galaxia (ascl:1101.007) to produces a synthetic survey, injects compact objects into the resulting survey, and then produces a list of microlensing events, enabling the discovery of black holes with microlensing. It can be used to examine historical microlensing events from photometric surveys to statistically constrain the abundance of black holes in our galaxy, and to forward model microlensing survey results to constrain, for example, the properties of compact objects, Galactic structure, and the initial-final mass relation.

[ascl:0202.001]
PopRatio: A program to calculate atomic level populations in astrophysical plasmas

PopRatio is a Fortran 90 code to calculate atomic level populations in astrophysical plasmas. The program solves the equations of statistical equilibrium considering all possible bound-bound processes: spontaneous, collisional or radiation induced (the later either directly or by fluorescence). There is no limit on the number of levels or in the number of processes that may be taken into account. The program may find a wide range of applicability in astronomical problems, such as interpreting fine-structure absorption lines or collisionally excited emission lines and also in calculating the cooling rates due to collisional excitation.

[ascl:1602.018]
POPPY: Physical Optics Propagation in PYthon

Perrin, Marshall; Long, Joseph; Douglas, Ewan; Sivaramakrishnan, Anand; Slocum, Christine; and others

POPPY (Physical Optics Propagation in PYthon) simulates physical optical propagation including diffraction. It implements a flexible framework for modeling Fraunhofer and Fresnel diffraction and point spread function formation, particularly in the context of astronomical telescopes. POPPY provides the optical modeling framework for WebbPSF (ascl:1504.007) and was developed as part of a simulation package for JWST, but is available separately and is broadly applicable to many kinds of imaging simulations.

[ascl:2007.006]
PoPE: Population Profile Estimator

PoPE (Population Profile Estimator) analyzes spatial distribution or internal spatial structure problems of samples of astronomical systems. This population-based Bayesian inference model uses the conditional statistics of spatial profile of multiple observables assuming the individual observations are measured with errors of varying magnitude. Assuming the conditional statistics of the observables can be described with a multivariate normal distribution, the model reduces to the conditional average profile and conditional covariance between all observables. The method consists of two steps: (1) reconstructing the average profile using non-parametric regression with Gaussian Processes and (2) estimating the property profiles covariance given a set of independent variable. PoPE is computationally efficient and capable of inferring average profiles of a population from noisy measurements without stacking and binning nor parameterizing the shape of the average profile.

[ascl:2407.018]
pony3d: Efficient island-finding tool for radio spectral line imaging

pony3d statistically identifies islands of contiguous emission inside a three-dimensional volume. The primary functionality is the rapid and reliable creation of masks for the deconvolution of radio interferometric radio spectral line emission. It has been designed to run on the output of the wsclean imager (ascl:1408.023) whereby the individual FITS image per frequency plane enables a high degree of parallelism, but can work on any image set providing this criterion is met. Single channel island rejection is offered, along with 3D mask dilation and boxcar averaging. pony3d is also a prototype source-finding and extraction tool.

[ascl:1805.011]
PoMiN: A Post-Minkowskian N-Body Solver

PoMiN is a lightweight N-body code based on the Post-Minkowskian N-body Hamiltonian of Ledvinka, Schafer, and Bicak, which includes General Relativistic effects up to first order in Newton's constant G, and all orders in the speed of light c. PoMiN is a single file written in C and uses a fourth-order Runge-Kutta integration scheme. PoMiN has also been written to handle an arbitrary number of particles (both massive and massless) with a computational complexity that scales as O(N^2).

[ascl:2012.016]
Pomegranate: Probabilistic model builder

Pomegranate builds probabilistic models in Python that is implemented in Cython for speed. The code merges the easy-to-use API of scikit-learn with the modularity of probabilistic modeling, including general mixture and hidden Markov models and Bayesian networks, to allow users to specify complicated models without the need to be concerned about implementation details. The models are built from the ground up and natively support features such as multi-threaded parallelism and out-of-core processing.

[ascl:1912.001]
Polyspectrum: Computing polyspectra using an FFT estimator

Polyspectrum computes the polyspectrum from 3D grids using a fast Fourier transformation (FFT) estimator. The code, written in C and MPI-parallelized, support the computation of power- and bispectra; it also supports higher-order polyspectra, but streamlining the input data is required.

[ascl:2007.009]
polyMV: Multipolar coefficients converter

polyMV converts multipolar coefficients (alms in healpix order) into Multipole Vectors (MVs) and also Fréchet Vectors (FVs) given a specific multipole. The code uses MPSolve (ascl:2007.008) and is order of magnitudes faster than other existing public codes at high multipoles.

[ascl:1502.011]
PolyChord: Nested sampling for cosmology

PolyChord is a Bayesian inference tool for the simultaneous calculation of evidences and sampling of posterior distributions. It is a variation on John Skilling's Nested Sampling, utilizing Slice Sampling to generate new live points. It performs well on moderately high dimensional (~100s D) posterior distributions, and can cope with arbitrary degeneracies and multimodality.

[ascl:2404.006]
PolyBin3D: Binned polyspectrum estimation for 3D large-scale structure

PolyBin3D estimates the binned power spectrum and bispectrum for 3D fields such as the distributions of matter and galaxies. For each statistic, two estimators are available: the standard (ideal) estimators, which do not take into account the mask, and window-deconvolved estimators. In the second case, the computation of a Fisher matrix is required; this depends on binning and the mask, but does not need to be recomputed for each new simulation. PolyBin3D supports GPU acceleration using JAX. It is a sister code to PolyBin (ascl:2307.020), which computes the polyspectra of data on the two-sphere, and is a modern reimplementation of the former Spectra-Without-Windows (ascl:2108.011) code.

[ascl:2307.020]
PolyBin: Binned polyspectrum estimation on the full sky

PolyBin estimates the binned power spectrum, bispectrum, and trispectrum for full-sky HEALPix maps such as the CMB. This can include both spin-0 and spin-2 fields, such as the CMB temperature and polarization, or galaxy positions and galaxy shear. Alternatively, one can use only scalar maps. For each statistic, two estimators are available: the standard (ideal) estimators, which do not take into account the mask, and window-deconvolved estimators. For the second case, a Fisher matrix must be computed; this depends on binning and the mask, but does not need to be recomputed for each new simulation. PolyBin can compute both the parity-even and parity-odd components, accounting for any leakage between the two, for the bispectrum and trispectrum.

[ascl:1109.005]
PolSpice: Spatially Inhomogeneous Correlation Estimator for Temperature and Polarisation

PolSpice (aka Spice) is a tool to statistically analyze Cosmic Microwave Background (CMB) data, as well as any other diffuse data pixelized on the sphere.

This Fortran90 program measures the 2 point auto (or cross-) correlation functions w(θ) and the angular auto- (or cross-) power spectra C(l) from one or (two) sky map(s) of Stokes parameters (intensity I and linear polarisation Q and U). It is based on the fast Spherical Harmonic Transforms allowed by isolatitude pixelisations such as Healpix [for Npix pixels over the whole sky, and a C(l) computed up to l=lmax, PolSpice complexity scales like Npix1/2 lmax2 instead of Npix lmax2]. It corrects for the effects of the masks and can deal with inhomogeneous weights given to the pixels of the map. In the case of polarised data, the mixing of the E and B modes due to the cut sky and pixel weights can be corrected for to provide an unbiased estimate of the "magnetic" (B) component of the polarisation power spectrum. Most of the code is parallelized for shared memory (SMP) architecture using OpenMP.

[ascl:1603.018]
PolRadTran: Polarized Radiative Transfer Model Distribution

PolRadTran is a plane-parallel polarized radiative transfer model. It is used to compute the radiance exiting a vertically inhomogeneous atmosphere containing randomly-oriented particles. Both solar and thermal sources of radiation are considered. A direct method of incorporating the polarized scattering information is combined with the doubling and adding method to produce a relatively simple formulation.

[ascl:1405.014]
POLPACK: Imaging polarimetry reduction package

POLPACK maps the linear or circular polarization of extended astronomical objects, either in a single waveband, or in multiple wavebands (spectropolarimetry). Data from both single and dual beam polarimeters can be processed. It is part of the Starlink software collection (ascl:1110.012).

[ascl:1406.012]
POLMAP: Interactive data analysis package for linear spectropolarimetry

POLMAP provides routines for displaying and analyzing spectropolarimetry data that are not available in the complementary TSP package. Commands are provided to read and write TSP (ascl:1406.011) polarization spectrum format files from within POLMAP. This code is distributed as part of the Starlink software collection (ascl:1110.012).

[ascl:2102.011]
polgraw-allsky: All-sky almost-monochromatic gravitational-wave pipeline

Astone, Pia; Bejger, Michał; Bolek, Jan; Ciecieląg, Paweł; Dorosh, Orest; Garus, Aleksander; Królak, Andrzej; Nagy-Egri, Máté Ferenc; Piętka, Maciej; Pisarski, Andrzej; Poghosyan, Gevorg; Sieniawska, Magdalena; Skrzypiec, Rafał

polgraw-allsky searches for almost monochromatic gravitational wave signals. This pipeline searches for continuous gravitational wave signals in time-domain data using the F-statistic on data from a network of detectors. The software generates a parameter space grid, conducts a coherent search for candidate signals in narrowband time segments, and searches for coincidences among different time segments. The pipeline also estimates the false alarm probability of coincidences and follows up on interesting outliers.

[ascl:2402.006]
polarizationtools: Polarization analysis and simulation tools in python

polarizationtools converts, analyzes, and simulates polarization data. The different python scripts (1) convert Stokes parameters into linear polarization parameters with proper treatment of the uncertainties and vice versa; (2) shift electric vector position angle (EVPA) data points in time series to account for the 180 degrees ambiguity; (3) identify rotations of the EVPA e.g. in blazar polarization monitoring data according to various rotation definitions; and (4) simulate polarization time series as a random walk in the Stokes Q-U plane.

[ascl:1807.001]
POLARIS: POLArized RadIation Simulator

POLARIS (POLArized RadIation Simulator) simulates the intensity and polarization of light emerging from analytical astrophysical models as well as complex magneto-hydrodynamic simulations on various grids. This 3D Monte-Carlo continuum radiative transfer code is written in C++ and is capable of performing dust heating, dust grain alignment, line radiative transfer, and synchrotron simulations to calculate synthetic intensity and polarization maps. The code makes use of a full set of physical quantities (density, temperature, velocity, magnetic field distribution, and dust grain properties as well as different sources of radiation) as input.

[ascl:1505.018]
POKER: P Of K EstimatoR

POKER (P Of K EstimatoR) estimates the angular power spectrum of a 2D map or the cross-power spectrum of two 2D maps in the flat sky limit approximation in a realistic data context: steep power spectrum, non periodic boundary conditions, arbitrary pixel resolution, non trivial masks and observation patch geometry.

[ascl:2403.005]
Poke: Polarization ray tracing and Gaussian beamlet module for Python

Ashcraft, Jaren N.; Mulhal, Kenji; Douglas, Ewan S.; Kim, Daewook; Riggs, A.J. E.; Anche, Ramya M.; Brendel, Trent; Derby, Kevin Z.; Dube, Brandon D.; Jarecki, Quinn; Jenkins, Emory; Milani, Kian

Poke (pronounced /poʊˈkeɪ/ or po-kay) uses commercial ray tracing APIs and open-source physical optics engines to simultaneously model scalar wavefront error, diffraction, and polarization to bridge the gap between ray trace models and diffraction models. It operates by storing ray data from a commercial ray tracing engine into a Python object, from which physical optics calculations can be made. Poke provides two propagation physics modules, Gaussian Beamlet Decomposition and Polarization Ray Tracing, that add to the utility of existing scalar diffraction models. Gaussian Beamlet Decomposition is a ray-based approach to diffraction modeling that integrates physical optics models with ray trace models to directly capture the influence of ray aberrations in diffraction simulations. Polarization Ray Tracing is a ray-based method of vector field propagation that can diagnose the polarization aberrations in optical systems.

[ascl:2208.011]
POIS: Python Optical Interferometry Simulation

POIS (Python Optical Interferometry Simulation) provides the building blocks to simulate the operation of a ground-based optical interferometer perturbed by atmospheric seeing perturbations. The package includes functions to generate simulated atmospheric turbulent wavefront perturbations, correct these perturbations using adaptive optics, and combine beams from an arbitrary number of telescopes, with or without spatial filtering, to provide complex fringe visibility measurements.

[ascl:1408.005]
POET: Planetary Orbital Evolution due to Tides

POET (Planetary Orbital Evolution due to Tides) calculates the orbital evolution of a system consisting of a single star with a single planet in orbit under the influence of tides. The following effects are The evolutions of the semimajor axis of the orbit due to the tidal dissipation in the star and the angular momentum of the stellar convective envelope by the tidal coupling are taken into account. In addition, the evolution includes the transfer of angular momentum between the stellar convective and radiative zones, effect of the stellar evolution on the tidal dissipation efficiency, and stellar core and envelope spins and loss of stellar convective zone angular momentum to a magnetically launched wind. POET can be used out of the box, and can also be extended and modified.

[ascl:1907.006]
POCS: PANOPTES Observatory Control System

PANOPTES (Panoptic Astronomical Networked Observatories for a Public Transiting Exoplanets Survey) is a citizen science project for low cost, robotic detection of transiting exoplanets. POCS (PANOPTES Observatory Control System) is the main software driver for the PANOPTES telescope system, responsible for high-level control of the unit. POCS defines an Observatory class that automatically controls a commercially available equatorial mount, including image analysis and corresponding mount adjustment to obtain a percent-level photometric precision.

[ascl:2207.018]
pocoMC: Preconditioned Monte Carlo method for accelerated Bayesian inference

pocoMC performs Bayesian inference, including model comparison, for challenging scientific problems. The code utilizes a normalizing flow to precondition the target distribution by removing any correlations between its parameters. pocoMC then generates posterior samples, used for parameter estimation, with a powerful adaptive Sequential Monte Carlo algorithm manifesting a sampling efficiency that can be orders of magnitude higher than without precondition. Furthermore, pocoMC also provides an unbiased estimate of the model evidence that can be used for the task of Bayesian model comparison. The code is designed to excel in demanding parameter estimation problems that include multimodal and highly non–Gaussian target distributions.

[ascl:2011.025]
PNICER: Extinction estimator

PNICER estimates extinction for individual sources and creates extinction maps using unsupervised machine learning algorithms. Extinction towards single sources is determined by fitting Gaussian Mixture Models along the extinction vector to (extinction-free) control field observations. PNICER also offers access to the well-established NICER technique in a simple unified interface and is capable of building extinction maps including the NICEST correction for cloud substructure.

[ascl:1302.004]
pNbody: A python parallelized N-body reduction toolbox

pNbody is a parallelized python module toolbox designed to manipulate and interactively display very large N-body systems. It allows the user to perform complicated manipulations with only very few commands and to load an N-body system and explore it interactively using the python interpreter. pNbody may also be used in python scripts. pNbody contains graphical facilities for creating maps of physical values of the system, such as density, temperature, and velocities maps. Stereo capabilities are also implemented. pNbody is not limited by file format; the user may use a parameter file to redefine how to read a preferred format.

[ascl:2307.009]
pnautilus: Three-phase chemical code

The three-phase pnautilus chemical code finds the abundance of each species by solving rate equations for gas-phase and grain surface chemistries. It performs gas–grain simulations in which both the icy mantle and the surface are considered active, taking into account mantle photodissociation, diffusion, and reactions; the code also considers the competition among reaction, diffusion and evaporation.

[ascl:1010.065]
PN: Higher Post Newtonian Gravity Calculations

Motivated by experimental probes of general relativity, we adopt methods from perturbative (quantum) field theory to compute, up to certain integrals, the effective lagrangian for its n-body problem. Perturbation theory is performed about a background Minkowski spacetime to O[(v/c)^4] beyond Newtonian gravity, where v is the typical speed of these n particles in their center of energy frame. For the specific case of the 2 body problem, the major efforts underway to measure gravitational waves produced by in-spiraling compact astrophysical binaries require their gravitational interactions to be computed beyond the currently known O[(v/c)^7]. We argue that such higher order post-Newtonian calculations must be automated for these field theoretic methods to be applied successfully to achieve this goal. In view of this, we outline an algorithm that would in principle generate the relevant Feynman diagrams to an arbitrary order in v/c and take steps to develop the necessary software. The Feynman diagrams contributing to the n-body effective action at O[(v/c)^6] beyond Newton are derived.

[ascl:2205.001]
PMOIRED: Parametric Modeling of Optical Interferometric Data

PMOIRED models astronomical spectro-interferometric data stored in the OIFITS format. Parametric modeling is used to describe the observed scene as blocks such as disks, rings and Gaussians which can be combined and their parameters linked. It includes plotting, least-square fitting and bootstrapping estimation of uncertainties. For spectroscopic instruments (such as GRAVITY), tools are provided to model spectral lines and correct spectra for telluric lines.

[ascl:2107.003]
PMN-body: Particle Mesh N-body code

PMN-body computes the non-linear evolution of the cosmological matter density contrast. It is based on the Particle Mesh (PM) technique. Written in C, the code is parallelized for shared-memory machines using Open Multi-Processing (OpenMP).

[ascl:1102.015]
PMFASTIC: Initial condition generator for PMFAST

PMFASTIC is a parallel initial condition generator, a slab decomposition Fortran 90 parallel cosmological initial condition generator for use with PMFAST (ascl:1102.008). Files required for generating initial dark matter particle distributions and instructions are included, however one would require CMBFAST (ascl:9909.004) to create alternative transfer functions.

[ascl:1102.008]
PMFAST: Towards Optimal Parallel PM N-body Codes

The parallel PM N-body code PMFAST is cost-effective and memory-efficient. PMFAST is based on a two-level mesh gravity solver where the gravitational forces are separated into long and short range components. The decomposition scheme minimizes communication costs and allows tolerance for slow networks. The code approaches optimality in several dimensions. The force computations are local and exploit highly optimized vendor FFT libraries. It features minimal memory overhead, with the particle positions and velocities being the main cost. The code features support for distributed and shared memory parallelization through the use of MPI and OpenMP, respectively.

The current release version uses two grid levels on a slab decomposition, with periodic boundary conditions for cosmological applications. Open boundary conditions could be added with little computational overhead. Timing information and results from a recent cosmological production run of the code using a 3712^3 mesh with 6.4 x 10^9 particles are available.

[ascl:9909.001]
PMCode: Particle-Mesh Code for Cosmological Simulations

Particle-Mesh (PM) codes are still very useful tools for testing predictions of cosmological models in cases when extra high resolution is not very important. We release for public use a cosmological PM N-body code. The code is very fast and simple. We provide a complete package of routines needed to set initial conditions, to run the code, and to analyze the results. The package allows you to simulate models with numerous combinations of parameters: open/flat/closed background, with or without the cosmological constant, different values of the Hubble constant, with or without hot neutrinos, tilted or non-tilted initial spectra, different amount of baryons.

[ascl:2211.008]
pmclib: Population Monte Carlo library

Benabed, Karim; Cappé, Olivier; Cardoso, Jean-François; Fort, Gersende; Kilbinger, Martin; Prunet, Simon; Robert, Christian P.; Wraith, Darren

The Population Monte-Carlo (PMC) sampling code pmclib performs fast end efficient parallel iterative importance sampling to compute integrals over the posterior including the Bayesian evidence.

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