New Improved Operational Model for Cosmic Ray Effects in
Space PhysicsPeter Velinov, Simeon Asenovski, Lachezar Mateev
Institute for Space and Solar-Terrestrial Research, BAS
International Conference on Physics in Memoriam Acad. Prof. Matey Mateev
Alexander MishevInstitute for Nuclear Research and Nuclear Energy, BAS
Sodankyla Geophysical Observatory (Oulu unit)
AbstractThe influences of galactic and solar cosmic rays (CR) in the middle
atmosphere and lower ionosphere are mainly related to ionization and excitation. In this way, CR modify the electric conductivity in the middle atmosphere and the electric processes in it. One fundamental problem in the understanding of interaction between CR and the neutral components in the atmosphere is precisely determination of the electron production rate profiles.
The effects of galactic and solar cosmic rays in the middle atmosphere can be computed with our model CRIMA. We take into account the CR modulation by solar wind and the anomalous CR component also. A new analytical approach for CR ionization by protons and nuclei with charge Z in the lower ionosphere and the middle atmosphere is developed. For this purpose, the ionization losses (dE/dh) for the energetic charged particles according to the Bohr-Bethe-Bloch formula are approximated in different energy intervals (two ionization losses intervals, one charge Z decrease interval and intermediate coupling intervals).
Electron production rate profiles q(h) are determined by the numerical evaluation of a 3D integral with account of cut-off rigidities. For calculations are used computer algebra systems Wolfram Mathematica 7 and Maple 14, and Pascal procedures.
Contents of the presentation An introduction in Cosmic Ray Ionization Model for the
Atmosphere (CRIMA)
Reviews of the main results and computer simulations made by CRIMA
Some results by CORSIKA simulations in middle and lower atmosphere
Future development and conclusions
Introduction CR are main ionization agent in middle atmosphere and lower
ionosphere The influence of CR penetration in the Earth’s atmosphere is
important for understanding of the solar-terrestrial relationships and space weather
The presented model is developed on the base of Bohr-Bethe-Bloch theory for ionization losses due to charged particles penetration through substance
This new generalized model contributes to the better accuracy of the problem solution towards the experimental data
An intermediate transition region between neighbouring energy intervals is introduced and the charge decrease interval is taken into account
Cosmic ray spectra
Cosmic ray spectrum“knee”
“ankle”
104 m-2 s-1 ~ 109 eV 10-2 km-2 yr-1 ~1021 eV
Mathematical background
Energy intervals approximation in six steps of the ionization losses function according to Bohr-Bethe-Bloch theory and with account of experimental data :
E – kinetic energy of particles kT – thermal energy Interval 2 – charge decrease interval Z – charge of the penetrating particle
)1(
6 interval , MeV/n 105105 if 66.05 interval , MeV/n 105850 if 1.91 4 interval , MeV/n 850200 if 68 3 interval , MeV/n 200 if 231 2 interval ,MeV/n 0.150.15 if 1540
1 interval , MeV/n 15.0 if 1057.2
1
63123.02
32
53.02
77.02
223.0
5.03
EEZEZEEZEEEZ
ZEEEEkTE
dhdE a
a
Atmospheric cut-offs The energy cut-offs (atmospheric and geomagnetic) determined the
starting point of CR differential spectrum at the top of the atmosphere The atmospheric cut-offs are derived for those values of the traveling
substance path, which correspond to the actual energy interval of the ionization losses function
where:
- traveling substance pathρ(h) - neutral density in the atmosphere at altitude h H(h) – scale height
)2()()(1
~
1min
hHhdhh
dhdEdEh
h
h
E
E
h~
Energy cut offs in Intervals 1-3
Interval 1
Interval 2 (charge decrease interval)
Interval 3
)3(~1285 25.0
1
kThA
hEA
)4(~8.118515.09228.015.077.0/1
5.05.077.02
h
AkThEA
5.05.0277.13 15.03182.0 kTZEhE aA
77.077.02 15.0345.0 aEZ )5(~/87.40877.1/12 hAZ
Energy cut offs in Intervals 4-6 Interval 4
Interval 5
Interval 6
5.05.02
253.1
4 15.0081.0~04.104200 kTZhAZhEA
)6(200254.015.0088.053.1/177.177.177.077.02
aa EEZ
5.05.0232
5 15.01049.1850~91.1 kTZh
AZhEA
77.177.1377.077.023 2001067.415.0106.1 aa EEZ )7(200850018.0 53.153.1
24
2877.0
6 105.4~579.05000 ZhAZhEA 77.077.0245.05.0 15.01088.415.0 aEZkT
)8(]45,12572008501056.52001041.1 877,0/153.153.1377.177.13 aE
Boundary crossing between the different energy intervals
The boundary crossing defines the energy transfer over the interval limits
Boundary crossing between intervals 1 and 2
Boundary crossing between intervals 2 and 3
)9(~128515.008.115.02
77.077.05.021
h
AEhE k
)10(~8.11859.2 77.0/177.177.1
277.0
32
h
AEE
ZEhE aka
Boundary crossing between the different energy intervals
Boundary crossing between intervals 3 and 4
Boundary crossing between intervals 4 and 5
Boundary crossing between intervals 5 and 6
)12(~
/ 04.10485047.5485053.1/1253.1
54 hAZEhE k
)13(50003.3~
/ 91.15000 877.0877.0265 kEhAZhE
)11(~87.40820093.320077.1/12
53.153.177.143
h
AZEhE k
Initial energies for interval boundaries
They define the starting energy values of the interval limits before entering of charged particles in the atmosphere
Initial energy of boundary between intervals 1 and 2
Initial energy of boundary between intervals 2 and 3
)14(~8.118515.077.0/1
77.02;15.0
h
AhE
)15(~/87.40877.1/1277.1
3, hAZEhE aEa
Initial energies for interval boundaries
Initial energy of boundary between intervals 3 and 4
Initial energy of boundary between intervals 4 and 5
Initial energy of boundary between intervals 5 and 6
)16(~/04.10420053.1/1253.1
4,200 hAZhE
)17(~ / 91.1850 25,850 hAZhE
)18(~/579.05000877.0/12877.0
6,5000 hAZhE
Energy decrease laws in internal regions
They define the energy decrease in the energy intervals without boundary crossings
Energy decrease law in interval 1
Energy decrease law in interval 2
)19(~1285 25.0
1
h
AEhE k
)20(~8.1185 77.0/1
77.02
h
AEhE k
Energy decrease laws in internal regions
Energy decrease law in interval 3
Energy decrease law in interval 4
Energy decrease law in interval 5
Energy decrease law in interval 6
)21(~/87.40877.1/1277.1
3 hAZEhE k
)22(~/04.10453.1/1253.1
4 hAZEhE k
)23(~/91.1 25 hAZEhE k
)24(~/579.0877.0/12877.0
6 hAZEhE k
Electron production rate in 6 energy intervals with CR charge decrease
The improved CR ionization model includes the electron production rate terms in 6 energy intervals of the ionization losses function and 5 intermediate transition region terms between the basic intervals
Lower boundary of integration Emin. The following case of lower integration boundary is assumed:
kT EA1(h) Emin 0.15 < Ea MeV/n (25)
The lower bound of integration Emin is chosen as the maximum of the atmospheric cut-off and the geomagnetic cut-off rigidity
The case of vertical penetration of cosmic rays is considered This model can be extended to the 3-dimensional case in the Earth
environment with introduction of the Chapman function
Electron production rate in 6 energy intervals with CR charge decrease
15.0
15.0
5.021
5.01
min
2;15.0
2570E
hE
dEhEEDdEhEEDQhhq
hE
E
E
hE
aE
a
a
dEhEEDdEhEED3,
2;15.0
23.032
23.021540
hE
hE
dEhEEDdEhEEDZaE
4,200
3, 200
77.043
20077.0
32231
hE
hE
dEhEEDdEhEEDZ5,850
4,200 850
53.054
85053.0
4268
dEhEdhdEED
hE5
5000
5,850
hE
dEhEdhdEED
6,5000
500065
hE
dEhEEDZ6,5000
123.06
266.0
Results
• The electron production rate values are proportional to the square of the charge (Z2), flux intensity in the different energies and the neutral density in middle atmosphere
• Above 90 km ACR ionization dominates over GCR ionization
Results
• The geomagnetic cut offs reflect the influence of the geomagnetic field on the CR penetration in the middle atmosphere of the Earth.
• For the higher Rc are obtained the profiles with smaller values.
CORSIKA
CORSIKA (COsmic Ray SImulations for KAscade) is a program for detailed simulation of extensive air showers initiated by high energy cosmic ray particles
Hadronic interactions at lower energies are described either by the GHEISHA interaction routines, by a link to FLUKA
Version CORSIKA 6.970 from July 19, 2010 (D. Heck et al.)
Atmospheric cascade
Ionization yield function Y, Oulu model
ionEx
ExEExY 11),(),(
Ion rate
dEhEhYEDhqE
mm )(),(),(),(0
0 200 400 600 800
100
101
102
103
104
105Y
[sr c
m2 g-1
]
Atmospheric Depth [g cm-2]
Total ionization EM ionization Muon ionization Hadron ionization
1 GeV Protons
0 200 400 600 800 1000 1200102
103
104
105
106
10 GeV Protons Total Ionization EM ionization Muon ionization Hadron ionization
Y [s
r cm
2 g-1]
Atmospheric Depth [g cm-2]
0 200 400 600 800 1000
104
105
106
100 GeV Protons Total ionization EM ionization Muon ionization Hadron ionization
Y [s
r cm
2 g-1]
Atmospheric Depth [g cm-2]
0 200 400 600 800 1000104
105
106
107
Y [s
r cm
2 g-1]
Atmospheric Depth [g cm-2]
Total ionization EM ionization Muon ionization Hadron ionization
1 TeV Protons
Y ~ spectrum
0 200 400 600 800 1000102
103
104
105
Y [s
r cm
2 g-1]
Atmospheric Depth [g cm-2]
Total ionization EM ionization Muon ionization Hadron ionization
1.5 GeV Protons
0 200 400 600 800 1000
103
104
105
106
Total ionization EM ionization Muon ionization Hadron ionization
Y [s
r cm
2 g-1]
Atmospheric Depth [g.cm-2]
5 GeV protons steep spectrum70 deg inclined
0 200 400 600 800 1000 1200103
104
105
106
spectrum of 9 GeV protons
70 degrees inclined
Total ionization EM ionization Muon ionization Hadron ionization
Y [s
r cm2 g-1
]
Atmospheric Depth [g.cm-2]
0 200 400 600 800 1000103
104
105
106
spectrum of 15 GeV protons
70 degrees inclined
Total ionization EM ionization Muon ionization Hadron ionization
Y [s
r cm2 g-1
]
Atmospheric Depth [g.cm-2]
Comparison with experimental data
0 200 400 600 800 1000 12000
20
40
60
80
100
0 200 400 600 800 1000 12000
10
20
30
40
50
60
70
80
90
100
qsolar minimum
qsolar maximum
q [io
n pa
irs s-1 c
m-3]
Atmospheric Depth [g cm-2]
Experimental data
0 200 400 600 800 1000
102
103
104
105
106
Fluka Total ionization EM ionization Muon ionization Hadron ionization
Gheisha Total ionization EM ionization Muon ionization Hadron ionization
Yie
ld fu
nctio
n Y
[Ion
pai
rs s
r cm
2 g-1]
Atmospheric Depth [g cm-2]
15 GeV protons steep spectrum70 deg inclined
Impact of atmospheric models
0 200
4,0x104
8,0x104
1,2x105
summer profile winter profile US standard
Yie
ld fu
nctio
n Y
[sr c
m2 g-1
]
Atmospheric Depth [g cm-2]
Protons 1 GeV
200 400 600
0,0
2,0x107
4,0x107
summer profile winter profile US standard
Yie
ld fu
nctio
n Y
[sr c
m2 g-1
]
Atmospheric Depth [g cm-2]
1 TeV protons
Electron production rate in Titan’s atmosphere
SEP on 20 January 2005
100
1000
10000
100000
0,01 0,1 1 10 100 1000 10000
Rate 08h 00 40 N Rate 23h 00 40 N Rate 08h 00 60 N Rate 23h 00 60 N
Q [ion pairs s-1 cm-3]
Dep
th [
m, a
.s.l.
]
100
1000
10000
100000
10-1 100 101 102 103 104 105 106
Rate 08h 00 60N Rate 23h 00 60N Rate 08h 00 80N Rate 23h 00 80N
Q [ion pairs s-1 cm-3]
Dep
th [
m, a
.s.l.
]
Cosmic ray induced ionization
Solar Influence on ClimateThe general aim is to investigate the effects of solar variability on the climate of the lower and middle atmosphere. Variations in the solar spectral irradiance, as well as solar energetic particles and galactic cosmic rays may impacts on the thermodynamic, chemical, and microphysical structure of the atmosphere.
Space Weather "Space Weather" is a term related the science and applications
arising from short-term variations of the Sun, propagation of energetic particles and electromagnetic emissions throughinterplanetary space, and effects on technology and humans orbiting in geospace and on the Earth's surface. It includes rapid phenomenasuch as solar flares and coronal mass egections, effects of shockwaves at the magnetosphere, global magnetic storms
Future plans
Improvement of CRIMA
Application of CRIMA model
Ionization rate Atmospheric chemistry Comparison withexperimental data
Operational CRIMA model for computer simulations and visualization
Determination of basic parameters in heliophysics and space physics
THANK YOU FOR YOUR ATTENTION!
