Description

CAMB: Cosmological Boltzmann Code

CAMB (Code for Anisotropies in the Microwave Background) is a powerful and widely-used Fortran-90 code designed to compute the Cosmic Microwave Background (CMB) power spectra and related cosmological observables. It's a crucial tool for cosmologists and astrophysicists studying the early universe and the formation of large-scale structures.

Key Features:

• High Accuracy and Efficiency: CAMB employs sophisticated numerical techniques to achieve high accuracy in its calculations, while maintaining computational efficiency, even for complex cosmological models. This makes it suitable for both rapid exploration of parameter space and detailed, high-precision analyses.
• Comprehensive Cosmological Models: CAMB supports a broad range of cosmological models, including:
  • Standard ΛCDM: The standard six-parameter cosmological model (Ω_b, Ω_c, h, A_s, n_s, τ).
  • Extensions: Includes the flexibility to incorporate extensions such as massive neutrinos, varying dark energy equation of state, primordial gravitational waves, and non-standard recombination histories.
  • Customizable Parameters: Users have extensive control over cosmological parameters, allowing for tailored simulations based on specific research questions.
• Diverse Output: CAMB produces a wide array of outputs including:
  • CMB power spectra: Temperature and polarization (TT, EE, BB, TE) power spectra.
  • Matter power spectrum: Linear matter power spectrum.
  • Transfer functions: Information on the evolution of matter perturbations.
  • Lens-potential power spectrum: For weak lensing analyses.
• User-Friendly Interface: While being a powerful scientific tool, CAMB provides a relatively user-friendly interface. Its input parameters are specified through simple parameter files, making it accessible to both experienced and novice users. Extensive documentation and examples are available to aid users.
• Open Source and Widely Used: CAMB is open-source software, fostering collaboration and community development. Its widespread use in the cosmological community ensures a high level of scrutiny, testing, and validation. This leads to high confidence in its results and reliability.
• Python Interface (CAMBpower): A convenient Python wrapper, CAMBpower, simplifies the use of CAMB, providing more user-friendly access to its functionality.

Applications:

• Parameter Estimation: Inferring cosmological parameters from CMB data using Bayesian or other statistical methods.
• Model Comparison: Testing different cosmological models against observational data.
• Forecasting: Predicting the sensitivity of future CMB experiments.
• Weak Lensing Studies: Computing lensing power spectra for analyses of large-scale structure.
• Education and Research: CAMB serves as a valuable educational tool for students and researchers learning about cosmology.

System Requirements:

• Fortran 90 compiler (e.g., gfortran)
• Basic Linux/Unix environment (Windows compatibility may require additional setup)

In summary: CAMB is an indispensable tool for anyone involved in precision cosmology, providing a robust and versatile platform for computing CMB power spectra and related cosmological observables. Its accuracy, efficiency, and extensive capabilities make it a leading choice for researchers worldwide.