ASCL.net

Astrophysics Source Code Library

Making codes discoverable since 1999

Welcome to the ASCL

The Astrophysics Source Code Library (ASCL) is a free online registry and repository for source codes of interest to astronomers and astrophysicists, including solar system astronomers, and lists codes that have been used in research that has appeared in, or been submitted to, peer-reviewed publications. The ASCL is indexed by the SAO/NASA Astrophysics Data System (ADS) and Web of Science and is citable by using the unique ascl ID assigned to each code. The ascl ID can be used to link to the code entry by prefacing the number with ascl.net (i.e., ascl.net/1201.001).


Most Recently Added Codes

2025 Jun 12

[ascl:2506.005] VBMicrolensing: Microlensing computations for single, binary, and multiple lenses

VBMicrolensing performs efficient computation in gravitational microlensing events using the advanced contour integration method, supporting single, binary and multiple lenses. It calculates magnification by single, binary and multiple lenses, centroid of the images generated by single and binary lenses, and critical curves and caustics of binary and multiple lenses. It also computes complete light curves including several higher order effects, such as limb darkening of the source, binary source, parallax, xallarap, and circular and elliptic orbital motion.

VBMicrolensing is written as a C++ library and wrapped as a Python package; the code can be called from either C++ or Python. This package encompasses VBBinaryLensing (ascl:1809.004), which is at the basis of several platforms for microlensing modeling. VBBinaryLensing will still be available as a legacy software, but will no longer be maintained.

[ascl:2506.004] TESS-cont: TESS contamination tool

TESS-cont quantifies the flux fraction coming from nearby stars in the TESS photometric aperture of any observed target. The package identifies the main contaminant Gaia DR2/DR3 sources, quantifies their individual and total flux contributions to the aperture, and determines whether any of these stars could be the origin of the observed transit and variability signals. Written in Python, TESS-cont is based on building the pixel response functions (PRFs) of nearby Gaia sources and computing their flux distributions across the TESS Target Pixel Files (TPFs) or Full Frame Images (FFIs).

[ascl:2506.003] SMART: Forward-modeling framework for spectroscopic data

SMART (Spectral Modeling Analysis and RV Tool) forward models spectral data. The method works best in those spectral orders with both strong telluric absorption features for accurate wavelength calibration and sufficient structure in the stellar spectrum to distinguish it from the telluric absorption. The code uses Markov Chain Monte Carlo (MCMC) methods to determine stellar parameters such as effective temperature, surface gravity, and rotational velocity, and calibration factors, including continuum and wavelength corrections, instrumental line-spread function (LSF), and strength of telluric absorption. SMART has been used with Keck/NIRSPEC, SDSS/APOGEE, Gemini/IGRINS high-resolution near-infrared spectrometers, among others, and with medium-resolution spectrometers, including Keck/OSIRIS and Keck/NIRES

[ascl:2506.002] MAGIC: Automatic analysis of realistic microlensing light curves

The MAGIC (Microlensing Analysis Guided by Intelligent Computation) PyTorch framework efficiently and accurately infers the microlensing parameters of binary events with realistic data quality. The code divides binary microlensing parameters into two groups, which are inferred separately with different neural networks. The neural controlled differential equation handles light curves with irregular sampling and large data gaps. MAGIC can achieve fractional uncertainties of a few percent on the binary mass ratio and separation, and can locate the degenerate solutions even when large data gaps are introduced. As irregular samplings are common in astronomical surveys, this code may be useful for other time series studies.

2025 Jun 10

[ascl:2506.001] CTD: Cumulative Time Dilation

Cumulative Time Dilation (CTD) calculates and plots the total time dilation experienced by a point (Earth) located at the center of a spherical mass-energy distribution. There are both analytical and numerical solutions for two different descriptions of how gravity acts across cosmological distances. The calculations are done for universes filled with a single energy type (dark energy; matter, including dark matter; or radiation) as well as the concordance model.

2025 May 31

[ascl:2505.020] Hibridon: Time-independent non-reactive quantum scattering calculations

Hibridon solves the close-coupled equations which occur in the quantum treatment of inelastic atomic and molecular collisions. Gas-phase scattering, photodissociation, collisions of atoms and/or molecules with flat surfaces, and bound states of weakly-bound complexes can be treated.

[ascl:2505.019] AIRI: Algorithms for computational imaging

The AIRI (AI for Regularization in radio-interferometric Imaging) algorithms are Plug-and-Play (PnP) algorithms propelled by learned regularization denoisers and endowed with robust convergence guarantees. The (unconstrained) AIRI algorithm is built on a Forward-Backward optimization algorithmic backbone enabling handling soft data-fidelity terms. AIRI's primary application is to solve large-scale high-resolution high-dynamic range inverse problems for RI in radio astronomy, more specifically 2D planar monochromatic intensity imaging.

[ascl:2505.018] SCATTERING: Solve the coupled equations for a given scattering system

The SCATTERING code solves the coupled equations for a given scattering system, provides the scattering S-matrix elements, and calculates the state-to-state cross-sections. Its approach is different from codes such as MOLSCAT (ascl:1206.004) or Hibridon (ascl:2505.020), as SCATTERING solves coupled equations in the body-fixed (BF) frame, where the coupling matrix exhibits a predominantly block-diagonal structure with blocks interconnected by centrifugal terms. This significantly reduces computational time and memory requirements.

[ascl:2505.017] TD-CARMA: Estimates of gravitational lens time delays with flexible CARMA processes

TD-CARMA estimates cosmological time delays to model observed and irregularly sampled light curves as realizations of a continuous auto-regressive moving average (CARMA) process using MultiNest (ascl:1109.006) for Bayesian inference. TD-CARMA accounts for heteroskedastic measurement errors and microlensing, an additional source of independent extrinsic long-term variability in the source brightness.

[ascl:2505.016] iSLAT: Interactive Spectral-Line Analysis Tool

iSLAT (the interactive Spectral-Line Analysis Tool) provides an interactive interface for the visualization, exploration, and analysis of molecular spectra. Synthetic spectra are made using a simple slab model; the code uses molecular data from HITRAN. iSLAT has been tested on spectra at infrared wavelengths as observed at different resolving powers (R = 700-90,000) with JWST-MIRI, Spitzer-IRS, VLT-CRIRES, and IRTF-ISHELL.