3 List of Namelist Commands

The namelist commands in the command input file define the whole problem: the ring parameters, the bunch distribution of the beam, the cavity HOM impedances, the optional instructions to setup the calculation, and the calculation itself. Each namelist commands use variables which further specify the command.

The namelist commands are processed by subroutines from object libraries made available publicly by M. Borland.

Below, the namelist commands in clinchor are listed and grouped according to their function:

The following pages describe all the namelist commands. For each command, one will find:

• the type and function of the command,
• a command definition listing, and
• a detailed explanation of the variables of the command.

The command definition listing is of the form

The component <variable-type> can be one of three types:

• double — for a double-precision type, used for most physical quantity variables,
• long — for an integer type, used for some physical quantity variables, such as the harmonic number, but most often for the logical flag variables, where 0 mean false and 1 means true.
• STRING — for a character string enclosed in double quotes, used most often for a filename variable.

Note that the component <variable-type> appears in these pages only as a place-holder, and shouldn’t be used literally in an actual input file.¹ The namelist in an input file should look like this:

The square brackets denotes an optional component. Not all variables need to be defined – the defaults may be sufficient. Those that do need to be defined are noted in the detailed explanations. The only variables that don’t have default values in general are string variables.

Array variables take a list of values with the first one assigned to the array element index. If the index value isn’t given, then the namelist processor assumes the first array element is number zero. The case of the letters in all namelist and variable names is important.

One will note that quantities which aren’t traditionally described in MKS units have their units appearing explicitly in their names. This convention is used to avoid confusion about which non-MKS units to use.

Whenever a namelist is read, it is written back to the standard output file, which is the screen device unless the output is redirected.

In general, the namelist commands can be repeated as many times as one wishes. The reason for repeating may be to change a variable value between calculation commands, to assemble HOM definitions in a modular way, or to construct a more complex bunch pattern.