This card follows the general FLUKA format (see description in 6}). It can be in free format if the latter has been requested with option FREE. The rest of the geometry must be in a special fixed format described below, unless free geometry format has been requested by a GLOBAL command at the beginning of input. The meanings of the WHAT andSDUMparameters are:WHAT(1): >0 switches on online parenthesis expansion. If during expansion at initialization the length of an expression (measured in number of terms) exceeds the original length by a factor NINT(WHAT(1)), expansion is aborted and online parenthesis expansion is used.WHAT(2): absolute accuracy parameter (Aa) in units of 10**-6 cm. It is used for tracking and boundary identification. Aa should be larger than Ar*L , where L is the largest coordinate value in the geometry description (excluding the outer blackhole shell containing it and Ar is the relative accuracy achievable in double precision (of the order of 1.E-14 - 1.E-15).Default= 0.0001WHAT(3)> 0.0 : logical unit for geometry input. The name of the corresponding file must be input on the next card ifWHAT(3)is different from 5. Note that values ofWHAT(3)/= 5.0 and < 21.0 must be avoided because of possible conflicts with FLUKA pre-defined units.Default= 5.0 (i.e. geometry input follows)WHAT(4)> 0.0 : logical unit for geometry output. If different from 11, the name of the corresponding file must be input on the next card ifWHAT(3)= 0 or 5, otherwise on the card following the next one. Values ofWHAT(4)/= 11.0 and < 21.0 must be avoided because of possible conflicts with FLUKA pre-defined units.Default= 11.0 (i.e. geometry output is printed on the standard output)WHAT(5): parentheses optimisation level = i0 + i1 x 1000 i0 = 1: logical optimisation only activated 2: logical + "plane" optimisation activated 3: logical + "plane" + "bounding box" optimisation activated (Default: 3) i1 > 0 forces optimisation even if no parentheses are found in the region under scrutiny (Default: 0)WHAT(6): not usedSDUM= COMBINAT : Combinatorial geometry is used. See section on Combinatorial Geometry for input description Other geometries, available in older versions of FLUKA, are no longer supported.Default: COMBINATSDUM= COMBNAME : Combinatorial geometry is used in free format, and names can be used instead of body and region numbersDefault(option GEOBEGIN not given): not allowed! GEOBEGIN and GEOEND must always be present.