C14 and calibration resources
=============================

There are some interesting websites to learn about radiocarbon calibration and
related topics. Some of them have been useful during the development of this
software.

Other software
--------------

- OxCal_ is developed by the Oxford Radiocarbon Accelerator Unit: it's
  by far the most used calibration program
- CALIB_ is a radiocarbon calibration program. A command-line Linux
  version is available (non-free software, but works well)
- BCal_ is an on-line Bayesian radiocarbon calibration tool hosted by
  the Department of Probability and Statistics at the University of
  Sheffield
- ChronoModel_ is an open source application developed at CNRS for
  constructing chronologies in archaeology in combining Events, Phases
  and temporal constraints
- the rcarbon_ open source package for R enables calibration and
  analysis of radiocarbon dates and includes functions not only for
  basic calibration, uncalibration, and plotting of one or more dates,
  but also a statistical framework for building demographic and
  related longitudinal inferences from aggregate radiocarbon date
  lists
- the BChron_ open source package for R enables quick calibration of
  radiocarbon dates under various calibration curves (including user
  generated ones), age-depth modelling, Relative Sea Level Rate
  Estimation, and Non-Parametric Phase Modelling

.. _OxCal: http://c14.arch.ox.ac.uk/oxcal.html
.. _CALIB: http://calib.qub.ac.uk/calib/
.. _BCal: http://bcal.shef.ac.uk/
.. _ChronoModel: https://chronomodel.com/
.. _rcarbon: https://github.com/ahb108/rcarbon
.. _BChron: https://cran.r-project.org/package=Bchron

Reference websites
------------------

- `Oxford Radiocarbon Accelerator Unit`_ contains a detailed explanation of how
  to use C14 datings and how calibration_ works
- Radiocarbon_ is the main international journal of record for research
  articles and date lists relevant to 14C and other radioisotopes and
  techniques used in archaeological, geophysical, oceanographic, and related
  dating techniques
- `radiocarbon WEB-info`_ provides online information concerning the
  radiocarbon dating method

.. _`Oxford Radiocarbon Accelerator Unit`: http://c14.arch.ox.ac.uk/
.. _calibration: http://c14.arch.ox.ac.uk/calibration.html
.. _Radiocarbon: http://radiocarbon.org/
.. _`radiocarbon WEB-info`: http://www.c14dating.com/

Calibration curves
------------------

Calibration curves are released in the public domain and can be
downloaded in their native format, a slightly customised CSV, from the
IntCal_ website.

.. _IntCal: http://intcal.org/

Please note that IOSACal already includes the calibration curves listed below:

- *IntCal20*
- *Marine20*
- *ShCal20*
- *IntCal13*
- *Marine13*
- *ShCal13*
- *IntCal09*
- *Marine09*
- *IntCal04*
- *Marine04*
- *ShCal04*
- *IntCal98*
- *Marine98*

IntCal20 and the associated Marine20 and ShCal20 curves are the latest
calibration curves. Older calibration curves are useful to reproduce
calibration results found in published literature.

This is a short list of the published literature for the IntCal
calibration data:

- Heaton, T. J. et al. (2020) ‘MARINE20—THE MARINE RADIOCARBON AGE CALIBRATION CURVE (0–55,000 CAL BP)’, Radiocarbon, pp. 1–42. doi: 10.1017/RDC.2020.68.
- Hogg, A. G. et al. (2013) ‘SHCal13 Southern Hemisphere Calibration, 0–50,000 Years cal BP’, Radiocarbon, 55(4), pp. 1889–1903.
- Hogg, A. G. et al. (2020) ‘SHCal20 SOUTHERN HEMISPHERE CALIBRATION, 0–55,000 YEARS CAL BP’, Radiocarbon, pp. 1–20. doi: 10.1017/RDC.2020.59.
- Hughen, K. A. et al. (2004) ‘Marine04 marine radiocarbon age calibration, 0-26 cal kyr BP.’, Radiocarbon, 46(3), pp. 1059–1086.
- McCormac, F. G. et al. (2004) ‘SHCal04 Southern Hemisphere calibration, 0-11.0 cal kyr BP.’, Radiocarbon, 46(3), pp. 1087–1092.
- Reimer, P. J. et al. (2004) ‘IntCal04 terrestrial radiocarbon age calibration, 0-26 cal kyr BP.’, Radiocarbon, 46(3), pp. 1029–1058.
- Reimer, P. J. et al. (2009) ‘IntCal09 and Marine09 Radiocarbon Age Calibration Curves, 0-50,000 Years cal BP’, Radiocarbon, 51(4), pp. 1111–1150.
- Reimer, P. J. et al. (2013) ‘IntCal13 and Marine13 Radiocarbon Age Calibration Curves 0–50,000 Years cal BP’, Radiocarbon, 55(4), pp. 1869–1887.
- Reimer, P. J. et al. (2020) ‘THE INTCAL20 NORTHERN HEMISPHERE RADIOCARBON AGE CALIBRATION CURVE (0–55 CAL kBP)’, Radiocarbon, pp. 1–33. doi: 10.1017/RDC.2020.41.


Radiocarbon databases
---------------------

There are a few databases of radiocarbon dates that are available as
**open data**, and can be easily downloaded as CSV files for further processing.

- `EUROEVOL <http://openarchaeologydata.metajnl.com/articles/10.5334/joad.40/>`_
- `Mediterranean radiocarbon dates <http://crowdsourced.micropasts.org/project/MedRadiocarbon/>`_

Both databases are useful to experiment with many dates and apart from
their specific research aims and spatio-temporal coordinates, they are
incredibly useful as a learning resource.

Many more datasets are available through the c14bazAAR_ package for R.

.. _c14bazAAR: https://docs.ropensci.org/c14bazAAR/

Other databases are usually released under restrictive license terms
or unavailable to the public.
