This is a thin element. It cuts particle out of a box of dimensions cxplus,cxminus,cyplus,cyminus. This element is considered as part of the beam pipe and therefore is activated by the flag npipe

The definition of this element is

Element name,	1st number,	2nd number,	3rd number,	4th number
COLLIMATOR1,	cxplus [m],	cxminus [m],	cyplus [m],	cyminus [m]

NOTE: the sign of cxplus,cxminus,cyplus,cyminus are positive as drawn in the picture. If you put one of these number negative it inverts the direction (so you cat put the box completely off axis).

The data of this element are stored in the matrix alat(n,m). The first index in alat identifies the lattice element as found in the sequence of elements loaded from the lattice file. The number of elements is NELMAX. In the variable alength is stored the lattice length.

alat(n,1) =	//
alat(n,2) =	15 ( number coding the type of element) ;
alat(n,3) =	longitudinal coordinate at the enter face of the n-th lattice element;
alat(n,4) =	longitudinal coordinate at the exit face of the n-th lattice element;
alat(n,5) =	cxplus [m];
alat(n,6) =	cxminus [m];
alat(n,7) =	cyplus [m];
alat(n,8) =	//
alat(n,9) =	cyminus [m];
alat(n,10) =	//
alat(n,11) =	length of the n-th element [m]
alat(n,12) =	//
alat(n,13) =	//