The tuneDisplay application shows an overview of the deviation of actual read back values (Setpoints) to calculated values (Theoretical values) for all devices along a desired beamline chosen from a source, e.g. OLIS, to an experiment, e.g. TIGRESS in two graphs. Thereby on top of the page both the beamline information and the beam information as for example the beam energy and charge states are shown.
The tune overview displays the start of the beamline left hand side at the upper graph and the end at the right hand side of the lower graph. The different devices are displayed as they occur along the beamline. This should help to visualize how i.e. quadrupoles or steerers affects the beam in a matching section or for a transport section. For a good tune the deviation of the actual readback value (Setpoint) to the calculated value (Theoretical value) is small, ideally none.
Suggested definition of 'differences' to be shown by tuneDisplay for various devices:
- Quads (both magnetic and electrostatic):
The percent difference between the quad's calculated setpoint (current or voltage)
\left({SP}_{theo}\right)
and its actual setpoint\left({SP}_{act}\right)
.
\Delta = \frac{100 \cdot \left( {SP}_{act} - {SP}_{theo}\right)}{{SP}_{theo}}
- Electrostatic steerers:
The difference will be the actual steering voltage (steerer setpoint minus common plate setpoint)
\left(U_{act}\right)
minus the calculated steering voltage (steerer setpoint minus common plate setpoint)\left(U_{theo}\right)
, divided by the the full scale of the steerer supply (1000 V for most steerers in ISAC)\left(\Delta U\right)
, multiplied by the minimum source voltage\left(U_{min, \: source}\right)
over the actual source voltage\left(U_{act, \: source}\right)
.
\Delta = \frac{100 \cdot \left( U_{act} - U_{theo}\right)}{\Delta U} \cdot \frac{U_{min, \: source}}{U_{act, \: source}}
For a typical ISAC electrostatic steerer this becomes:
\Delta = \frac{100 \cdot \left( U_{act} - U_{theo}\right)}{1000} \cdot \frac{10}{U_{act, \: source}}
- Magnetic steerers:
The difference will be the actual steerer current
\left(I_{act}\right)
minus the calculated steerer current\left(I_{theo}\right)
, divided by the the full scale of the steerer supply (6 A or 200 A for most steerers in ISAC)\left(\Delta I\right)
, multiplied by the minimum beam rigidity\left( \left(B\rho\right)_{min} \right)
at that location over the actual beam rigidity\left( \left(B\rho\right)_{act} \right)
.
\Delta = \frac{100 \cdot \left( I_{act} - I_{theo}\right)}{\Delta I} \cdot \frac{\left(B\rho\right)_{min}}{\left(B\rho\right)_{act}}
For a typical 100 A ISAC magnetic steerer in MEBT this becomes:
\Delta = \frac{100 \cdot \left( I_{act} - I_{theo}\right)}{200} \cdot \frac{84 \left[\mathrm{kG} \cdot \mathrm{cm}\right]}{\left(B\rho\right)_{act}}
- Electrostatic dipoles:
The percent difference between the dipole's calculated plate setpoint
\left(U_{act}\right)
, which is the difference of the actual Voltage between the plates\left(\left(U_{-} - U_{+}\right)_{act}\right)
, and its actual common plate setpoint\left(U_{theo}\right)
, which is the difference of the theoretical Voltage\left(\left(U_{-} - U_{+}\right)_{theo}\right)
.
\Delta = \frac{100 \cdot \left( U_{act} - U_{theo}\right)}{U_{theo}}
- Magnetic dipoles:
The percent difference between the dipole's calculated field setpoint (Gauss)
\left(B_{theo}\right)
and its actual setpoint\left(B_{act}\right)
.
\Delta = \frac{100 \cdot \left( B_{act} - B_{theo}\right)}{B_{theo}}
- RF phases:
The difference between the calculated phase setpoint (in degrees)
\left(\varphi_{theo}\right)
and its actual setpoint\left(\varphi_{act}\right)
, normalized to 180 degrees.
\Delta = \frac{100 \cdot \left( \varphi_{act} - \varphi_{theo}\right)}{180}
- RF amplitudes:
The percent difference between the calculated amplitude setpoint (units unspecified)
\left(A_{theo}\right)
and its actual setpoint\left(A_{act}\right)
.
\Delta = \frac{100 \cdot \left( A_{act} - A_{theo}\right)}{A_{theo}}