New Features in PSRCHIVE 12.1

Polarimetric calibration: pcm has a number of new features, including the ability to

  • model a unique value of gain, differential gain, or differential phase for each observation of the reference source (typically a noise diode) [enabled with -U];
  • automatically reduce the number of free parameters in the fit, then retry failed solutions;
  • manually configure the model before fitting [using -e or -E]. For example, parameters 4 to 7 (inclusive) may be held constant with a command like pcm -e 'fit[4-7]=0'. Initial guesses of parameter values can similarly be set.
The pac program is now able to load multiple databases [by using -d multiple times]; this allows multiple databases to be merged for use.

Bugs Fixed:

See the Bugs Tracker.

New Features in PSRCHIVE 12.0

Fourth-order moments: Support has been implemented for handling the fourth-order moments of the electric field, such as the four-dimensional covariance matrix of the Stokes parameters. Support includes input/output in PSRFITS files, as well as propagation through various algorithms, including polarimetric calibration, dedispersion, and integration over frequency channels and sub-integrations.

Rotating Vector Model: A new program, psrmodel, implements a novel algorithm for fitting the linear polarization profiles (Stokes Q and U) directly to the rotating vector model (RVM) by modeling the complex-valued L=Q+iU.

Bugs Fixed:

See the Bugs Tracker.