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• GeoMagSphere Web Calculators

GeoMagSphere data sets and results can be freely downloaded or copied. However, the user should make the appropriate acknowledgment or citation, e.g., see  Citations or Bibliography  pages. The data generated by using the Calculator may be used by GeoMagSphere developers for statistical purpose.

• Vertical Rigidity Cutoff

In this page we provide the possibility to perform the Vertical Rigidity Cutoff calculation with our bactracing code, using  two different External Field models.

The following links give access to Tsyganenko 96 and Tsyganenko 2005 code:

## How to Use Rigidity Cutoff Calculator

The vertical Rigidity Cutoff Calculator evaluater allowed trajectories with the backtracing technique. Particles trajectories are reconstructed starting from the given location and with verical directions, with rigidity step of 0.1 GV, using the Internal Geomagnetic Field model IGRF and External Geomagnetic Field model choosen (Tsyganenko 96 or 05). For each rigidity step the particle backtracing ends once it reaches the two boudaries, or the magteopause on dayside and a limit at 25 Re on nightside, or the same starting altitude.

## Input Parameters

1. Year (from 1 Jan 1968 to 31 dec 2015)
2. Day Of Year (DOY)
3. Hour (from 0 to 23)
4. Latitude (from -88 to +88 deg.)
5. Longitude (from 0 to 360 deg.)
6. Radius in Earth Radii Re (from 1.00 to 10.00)

1.00 Re = 6371,2 km / 1.00 Re is the Earth surface

## CAVEAT

The Tsyganenko 96 model should be used for quiet solar periods, i.e. when the Solar Wind Pressure Pdyn is below the value of 4  nPa (the average solar wind pressure is 2 nPa). In disturbed periods we suggest to use the Tsyganenko 05 model, especially developed from Solar Events and thus tailored for Active Periods. Calculation can take 1-2 minutes and can run significantly longer for r > 1.1 Re.

## Tsyganenko 96 model

All info related to the Tsyganenko 96 Model used in our backtracing code can be found at this link: External Magnetic Field

## Tsyganenko 2005 Model

All info related to the Tsyganenko 96 Model used in our backtracing code can be found at this link: External Magnetic Field