CONAN.utils.aR_to_Tdur
======================

.. py:function:: CONAN.utils.aR_to_Tdur(aR, b, Rp, P, e=0, w=90, tra_occ='tra', total=True)

   convert scaled semi-major axis to transit duration in days
   using eqn 30 and 31 of Kipping 2010 https://doi.org/10.1111/j.1365-2966.2010.16894.x
   it is a more precise modification of eq 14,16 of Winn2010 https://arxiv.org/pdf/1001.2010.pdf

   :param aR: The scaled semi-major axis of the planet.
   :type aR: float, ufloat, array-like;
   :param b: The impact parameter.
   :type b: float, ufloat, array-like;
   :param Rp: planet-to-star radius ratio.
   :type Rp: float, ufloat, array-like;
   :param P: The period of the planet in days.
   :type P: float, ufloat, array-like;
   :param e: The eccentricity of the orbit.
   :type e: float, ufloat, array-like;
   :param w: The argument of periastron in degrees.
   :type w: float, ufloat, array-like;
   :param tra_occ: select duration of transit (tra) or occultation (occ)
   :type tra_occ: str;
   :param total: select total duration T14 (True) or full duration T23 (False)
   :type total: bool;

   :returns: **Tdur** -- The transit duration in days (same unit as P).
   :rtype: array-like;