def rayTracingResultsFileName(
    site, telescopeModelName, sourceDistance, zenithAngle, label
):
    """
    Ray tracing results file name.

    Parameters
    ----------
    site: str
        South or North.
    telescopeModelName: str
        LST-1, MST-FlashCam, ...
    sourceDistance: float
        Source distance (km).
    zenithAngle: float
        Zenith angle (deg).
    label: str
        Instance label.

    Returns
    -------
    str
        File name.
    """
    name = "ray-tracing-{}-{}-d{:.1f}-za{:.1f}".format(
        site, telescopeModelName, sourceDistance, zenithAngle
    )
    name += "_{}".format(label) if label is not None else ""
    name += ".ecsv"
    return name