NCF - ModelScale SRP disabled versus SRP factor 0

[Bemtgenj]

Hello

I am writing to you to see if you can help me with some variable settings

I used to run simulateAccelerometer/ Albedo to get the Abledo part of the non-conservative forces (see print screen and plot for GRAC-FO).

Now in the latest GROOPS version the Albedo (and SRP) are depreciated and replaced by modelScale/radiationPressure. So my thought was to disable factorSolarRadiation and get ERP. But then i got the following plot

which is different from the first one. However when i leave SRP enabled but set the factor from 1.0 to 0.0 i get the same plot as with the
original Albedo script

I thought that disabling the SRP would leave SRP out of the acceleration determination, but it seems setting it to 0 leaves it out of the acceleration determination? Isn't disabling and setting it to 0 the same? Maybe i missed something in the documentations that covers these setting differences?

The same question would then be valid for VariationalEqaution, VariationalEqautionOrbitFit, SimulateOrbit,, GNSSProcessing/RD, basically anytime forces or miscelAccelerations / radiationPressure is used? And the same logic will need to be applied for EarthRadiation and / or thermalRadiation acceleration?

The following plots show the difference using the albedo setting as baseline

thank you for helping out with using the proper settings and clarifying my confusion.

BR
Jean

[Bemtgenj]

Hello

I assume it has nothing to do with the typo in "radation" as the variable that is used is named factorSun.

[tmayerguerr]

Hi Jean,
If a config element is disabled, groops assumes the default value. In this case, this is 1.0, so if you want to use the factor 0.0, you must use it explicitly.
best regards
Torsten

[Bemtgenj]

Hi Torsten
Thank you very much for the feedback and the clarification

BR
Jean

[Bemtgenj]

Hi Torsten

Then i have a few more questions based on what you said above when i use the ProcessingVariationalEquation , ProcessingVariationalEquationOrbitFit, GNSS processing / parameter.dynamicorbits/ forces:

Setting A
miscAccel Radiation Pressure enabled
SRP disabled -> default factor = 1
ERP enabled -> factor 1
TRP enabled -> factor 1
=> this will use SRP, ERP, TRP in the processing with all having a of 1

Setting B
miscAccel Radiation Pressure enabled
SRP enabled -> factor 0
ERP enabled -> factor 1
TRP enabled -> factor 1
=> this will use RP, TRP in the processing and no SRP

Setting C
miscAccel Radiation Pressure enabled
SRP disabled -> default factor = 1
ERP enabled -> factor 1
TRP enabled -> factor 1
miscAccel AD enabled
AD enabled factor 0
=> this will use SRP, ERP, TRP in the processing an no AD (or AD at 0)

Setting D
miscAccel Radiation Pressure enabled
SRP enabled -> factor 1
ERP enabled -> factor 1
TRP enabled -> factor 1
miscAccel AD disabled
AD enabled factor 1
=> this will use SRP, ERP, TRP and AD at default setting of 1 the processing or no AD

Setting E
miscAccel Radiation Pressure enabled
SRP enabled -> factor 1
ERP enabled -> factor 1
TRP enabled -> factor 1
miscAccel AD disabled
AD disabled factor 0
=> this will use SRP, ERP, TRP and AD at default setting of 1 the processing or no AD at all?

I just want check if there is a difference between disabling the entire miscAcc versus disabling the different variables i.e SRP,ERP,TRP individually. Or in other words if i enabled miscAccel/RadiationPressure and disable miscAcc: AD then SRP,ERP,TRP are being included in the process and AD is not (no matter what the AD factor setting itself is)
NAd default setting for SRP, ERP, TRP, AD is 1.0

You can probably see how the confusion came about as there are different ways to enable disable settings and their consquences.

I realize now that the best way would have been not to include multiple miscAccel in the base program, I did this so that i had a standard program and just needed to to change the settings for various studies.

Thank you un advance for clarifying the settings of disabling. enabling at different levels.

BR
Jean