This will call make_lstar1 or make_lstar_shell_splitting_1 from the irbem library and will lookup omni values for given time if not provided (optional). If pitch angles are provided, drift shell splitting will be calculated and “Bmirr” will be returned. If they are not provided, then no drift shell splitting is calculated and “Blocal” is returned.
Parameters: | - ticks (Ticktock class) : containing time information
|
---|---|
Returns: | - results (dictionary) : containing keys: Lm, Lstar, Bmin, Blocal (or Bmirr), Xj, MLT
|
Notes
0 : no external field
MEAD : Mead & Fairfield [1975] (uses 0<=Kp<=9 - Valid for rGEO<=17. Re)
T87SHORT: Tsyganenko short [1987] (uses 0<=Kp<=9 - Valid for rGEO<=30. Re)
T87LONG : Tsyganenko long [1987] (uses 0<=Kp<=9 - Valid for rGEO<=70. Re)
T89 : Tsyganenko [1989] (uses 0<=Kp<=9 - Valid for rGEO<=70. Re)
OPQUIET : Olson & Pfitzer quiet [1977] (default - Valid for rGEO<=15. Re)
-100.<=Dst<=20. - Valid for rGEO<=60. Re)
there is no upper or lower limit for those inputs - Valid for xGSM>=-15. Re)
W1, W2, W3, W4, W5, W6 - no upper or lower limit for inputs - Valid for xGSM>=-15. Re)
Kp: value of Kp as in OMNI2 files but has to be double instead of integer type
Dst: Dst index (nT)
dens: Solar Wind density (cm-3)
velo: Solar Wind velocity (km/s)
Pdyn: Solar Wind dynamic pressure (nPa)
ByIMF: GSM y component of IMF mag. field (nT)
BzIMF: GSM z component of IMF mag. field (nT)
previous 1 hour, Vsw is the solar wind speed, Bperp is the transverse IMF component (GSM) and theta it’s clock angle.
Vsw is solar wind speed, Bs=|IMF Bz| when IMF Bz < 0 and Bs=0 when IMF Bz > 0, a=0.005.
Vsw is the solar wind speed, Dsw is the solar wind density, Bs=|IMF Bz| when IMF Bz < 0 and Bs=0 when IMF Bz > 0.
W1 - W6: see definition in (JGR-A, v.110(A3), 2005.) (PDF 1.2MB)
AL: the auroral index
1st element: 0 - don’t compute L* or phi ; 1 - compute L*; 2- compute phi
n - n is the frequency (in days) starting on January 1st of each year (i.e. if options(2nd element)=15 then IGRF will be updated on the following days of the year: 1, 15, 30, 45 ...)
good ratio precision/computation time (i.e. an error of ~2% at L=6). The higher the value the better will be the precision, the longer will be the computing time. Generally there is not much improvement for values larger than 4. Note that this parameter defines the integration step (theta) along the field line such as dtheta=(2pi)/(720*[options(3rd element)+1])
the precision, the longer will be the computing time. It is recommended to use 0 (usually sufficient) unless L* is not computed on a LEO orbit. For LEO orbit higher values are recommended. Note that this parameter defines the integration step (phi) along the drift shell such as dphi=(2pi)/(25*[options(4th element)+1])