Source code for orbit.py_linac.lattice_modifications.sns_aperture_additions

#!/usr/bin/env python

# --------------------------------------------------------------
# Function to add the aperture class instances to the SNS linac lattice.
# These apertures are not belong to the particular accelerator elements,
# so we created them as markers: MEBT:ChpPlt:Entr and MEBT:ChpPlt:Exit
# --------------------------------------------------------------

import math
import sys
import os

from orbit.py_linac.lattice import LinacApertureNode
from orbit.py_linac.lattice import Quad


def AddMEBTChopperPlatesAperturesToSNS_Lattice(accLattice, aprtNodes):
    """
    Function will add two Aperture nodes at the entrance and exit of
    MEBT chopper plates. It returns the list of Aperture nodes.
    """
    x_size = 0.060
    y_size = 0.018
    shape = 3
    node_pos_dict = accLattice.getNodePositionsDict()
    node1 = accLattice.getNodesForName("MEBT:ChpPlt:Entr")[0]
    node2 = accLattice.getNodesForName("MEBT:ChpPlt:Exit")[0]
    for node in [node1, node2]:
        node_name = node.getName()
        (posBefore, posAfter) = node_pos_dict[node]
        apertureNode = LinacApertureNode(shape, x_size / 2.0, y_size / 2.0, posBefore)
        apertureNode.setName(node_name + ":Aprt")
        apertureNode.setSequence(node.getSequence())
        node.addChildNode(apertureNode, node.ENTRANCE)
        aprtNodes.append(apertureNode)
    aprtNodes = sorted(aprtNodes, key=lambda x: x.getPosition(), reverse=False)
    return aprtNodes