def METHOD_NAME(self, value):
    """Update the resolution when energy changed.
    Args:
        value(float): Energy [keV]
    """
    value = value or HWR.beamline.energy.get_value()
    _wavelength = HWR.beamline.energy.calculate_wavelength(value)
    _distance = self._hwr_detector.distance.get_value()
    _radius = self._hwr_detector.get_radius(_distance)
    try:
        ttheta = atan(_radius / _distance)
        if ttheta:
            self._nominal_value = _wavelength / (2 * sin(ttheta / 2))
            self.emit("valueChanged", (self._nominal_value,))
    except (TypeError, ZeroDivisionError):
        logging.getLogger().exception("Error while calculating resolution")