Impact of Solar X-ray Flares on the Earth lower ionosphere
relating LYRA – GOES - VLF data
Vida Žigman, UNG, Nova Gorica,SloveniaDavorka Grubor, UB, Belgrade, Serbia
Desanka Šulić, IP, Belgrade, SerbiaCraig Rodger, James Brundell, Department of Physics,
University of Otago, Dunedin, New ZealandMark Clilverd, British Antarctic Survey, Cambridge,UK
ESWW9 / PROBA2 splinter
JOINT WORKING GROUP
GOES
SDO
In Space:
Observe and
measure
Flares!
LYRA?
SOHO
OBSERVATIONS
• Observations of the effects of Solar X-ray flares from Earth –VLF transmission
• How we correlate with space based measurements – GOES
• How we model: N(t,h), LWPM• Can we exploit LYRA data? • Results• Summary
OUTLINE
74 km
On Earth:
D-region
Radiowavepropagation(Supported by NOSC LWPC)
Tx:NWC
Rx:AbsPAL,AwesomeBeograd
Solar Lyman Alpha (121.6 nm)during flares: Solar X-rays measure
AMPLITUDE& PHASE
DISTURBANCESVLF
f < 30 kHz
OBSERVATIONS:
Radiowave propagation
TRANSMITTER Tx:Harold E. HoltNorth West CapeNWC (21.S ;114.2 E)
RECEIVERs Rx:Beograd (44.85 N; 20.38 E)
AbsPAL
AWESOME
View from ArcticNAA/24.0 kHz
Antarctic-ArcticRadiation-belt Dynamic) Deposition –VLF Atmospheric Research Konsortia
e.g.Tx: :NAA/24.0 kHz :(44.65 N; 67.3 W)
GQD/22.1 kHz :(54.72 N; 02.88 W) ICV/20.3 kHz:(40.92 N;9.73W)NWC/19.8 kHz:(21.8S; 114.2 E)
BGAbsPAL
Rx:
Scott
Gde je NPM?
Casey Scott B.
NWC/19.8 kHz
SCIENCE TOPICS
• SPE• REP• SOLAR FLARES
NPM/21.4 kHz
00:00 04:00 08:00 12:00 16:00 20:00 24:00
1E-6
1E-5
1E-4
-68
-66
-64
-62
-60
-58
-100
0
100
200
10-3
time UT
0200 UTC4.7
I x [w
/m-2]
0353 M6.3
0.1-0.8 nm GOES15_20120309
0128 UTC2
NWC20120309_Casey_1min
ampl
itude
[dB
]
0350.5 UT0350.5 UT
NWC - Casey : VLF Amplitude & Phase
I [W
/m2 ]
0357 UT 6-20 nm + X ray
1E-6
1E-5
1E-4
1E-3
-96
-90
-84
-78
-72
-66
00:00 04:00 08:00 12:00 16:00 20:00 24:00
10-3
-450
0
450
0348 UT
I [w
/m-2]
I x
[w/m
-2]
0353 UTM6.3
0.1-0.8 nm GOES15_20120309VLF NPM20120309_Casey
ampl
itude
[dB
]
0357 UT ch2-4(Zr); 6-20 nm + X ray
time UT
NPM - Casey : VLF Amplitude & Phase
pha
se [d
eg]
0349 UT
OBSERVATIONS
NPM/21.4 kHz
VLF: AMPLITUDEPHASEat
CASEY
Flare – active 9March 2012
Solar Irradiance
GOES 15 LYRA
NWC/19.8 kHz
Maine NAA/24.0 kHz at BELGRADE Flare – active 17July 2004
-1 5 0-1 0 0
-5 00
5 01 0 0
4 04 55 05 56 06 5
1 0 -71 0 -6
1 x 1 0 -51 x 1 0 -4
NAA/24.0 kHz
phas
e (d
eg)
t ime UT
1 7 0 7 20 0 4
1 7 0 7 20 0 4
1 9 5 016 5 01 3 5 01 0 5 0
NAA/24.0 kHz
ampl
itude
(r
elat
ive
dB)
0 7 50
GO ES-120.1-0.8 nm
I (W
/m2 )
1 7 0 7 20 0 4
X1.1 0757 UT 110µW/m2
C7.3 1137 UT 7.3µW/m2
M2.5 1651 UT 25.4µW/m2
dB5min3
=∆=∆
At
M2.5
dB3min2
=∆=∆
At
C7.3
56
58
60
62
64
1639 1659 1719 1739 1759
10-6
1x10-5
50
100
150
200GOES-12 0.1-0.8 nm
1654 UT
1651 UT
ampl
itude
(re
lativ
e d
B)
17072004
NAA/24.0 kHz
I (W
/m2 )
time UT
phas
e (d
eg)
LWPC model
For quiet ionosphereInitial concentration N(t=0, h)
Wait model of the quiet ionosphere (1970)
-sharpness, H’ – reflection heightβ
NOSC: Computer programme for the assessment of long wave Propagation Long Wavelength Propagation Capability,
Input :Tx and Rx coordinates Time Angle of magnetic inclination Conductivity
For solar-flare conditions:N(h),
To validate the N(t,h) model
β H’
Output :VLF amplitude and phase along the trace, from Tx to Rx
0 2000 4000 6000 8000 10000 1200030
60
90
120
am
plitu
de [d
B]
D [km] along GCP
LWPC quiet
NPM-Cas 07/03/12; LWPC for X1.4 at 01:15 UT
-400
-200
0
200
400
pha
se [d
eg]
NPM-Cas 07/03/12; LWPC for X1.4 at 01:15 UT
0 2000 4000 6000 8000 10000 12000
D [km] along GCP
NAA/24.0 kHz 17July 2004, 1651 UT
OBSERVATIONS - MODELLING:
Time delay (Appleton,1953, Journal of Atm. Terrestrial Physics JATP, 3, 282) “slugishness”(time shift of maximum N with respect to regular diurnal fluxat χ=0)
Amax , Imax ,, I(Amax) , A(Imax)
maxmax IAttt −=∆
KEY parameters:MEASUREMENTS:2004 -2007…2010...2012I(t), A(t), P(t)
maxmax NAtt ≡
)()( maxmax N IA I ≡
Assumption:
56
58
60
62
64
1639 1659 1719 1739 1759
10-6
1x10-51654 UT
1651 UT
ampl
itude
[dB
]
17072004 NAA/24 [kHz]
I X x
106
[W/m
2 ]
time UT
t∆ > 0A∆ > 0A∆ < 0
300 , 250 events
Multicomponent hydrodynamics N,N+,N-
q = (C/eH )I
q( t ) = k I (t)
q - rate of electron productionC –number of electrons per unit of energyH - scale height– solar zenith angle e –base of natural logarithm
?,αk
2Nqdt
dN α−=
χcos
χcoseH
Ck ≡
( )λλα
λ +−−
+=
1
1
)1(2
dt
dNN
q
dt
dN
Continuity equationelementary process kinetics
- effective electron recombination coefficient
MODELLING:
time dependence!
11.4 11.5 11.6 11.7 11.8 11.9 12
1× 109
2× 109
3× 109
4× 109
5× 109
6× 109
7× 109
Time UT
I (t)
from NOAAwww.sec.noaa.gov
From LWPC or IRI:preflare N(t=0)
α
χ
Why not LYRA?
Time delay , but for the active ionosphere:
tIN
∆=
α21
)( max ),,,( maxmaxmax IktNN α∆= (1)
α)(
)( maxmaxNkI
N DE =2Nqdt
dN α−= (2)
Agreement of (1) i (2) yields:
.constk =αq( t ) = k I (t), χcos
eH
Ck ≡
5× 1012
1× 1013
1.5× 1013
2× 1013
5× 10-13
1× 10-12
1.5× 10-12
2× 10-12
0
1
2
3
4
5
5× 1012
1× 1013
1.5× 1013
5× 101× 10-12
1.5× 10-12
2× 10
1/Jm][k
min][t∆
]sm[ -13α
5× 10121× 1013
1.5× 1013
2× 1013
5× 10-13
1× 10-12
1.5× 10-12
2× 10-12
0
1
2
3
4
5
5× 101× 10-12
1.5× 10-12
2×
0
1
2
3
4
]sm[ -13α1/Jm][k
min][t∆
0 5× 1012 1× 1013 1.5× 1013 2× 10130
5× 10-13
1× 10-12
1.5× 10-12
2× 10-12
.constk =αFriedrich et al. 1999, Adv. Space Res. Osepian et al. 2009 ,
Ann.Geophys
RECENT advances - extension to different heights
170704_1137 C7.3
e.g.
min)',( tt ∆∆(2, 1.92)
= 8.75 10-13 m3 s-1
q(t) = 3.73 1012 I(t) [m-3 s-1]
11.4 11.5 11.6 11.7 11.8 11.9 12
1× 109
2× 109
3× 109
4× 109
5× 109
6× 109
7× 109
Time UT
N [m
-3],
I x
1015
[Wm
-2]
17072004_1137 C7.3
Nmax= 5.23 109 m-3
N(Imax)= 4.86 109 m-3Height: 74km,
N(t=0):2.18 x 108 m-3
RESULTS
NAA/24.0 KHz
Žigman et al., 2007, Grubor et al., 2008,Journal of Atm. Solar-Terrestrial Physics Ann. Geophys
α
60 65 70 75 80 85 90
108
109
1010
1011
1012
X3.9X1.1M2.5M1.6C8.8C2.5M1.0X1.4
Nm
ax [m
-3]
height [km]
C2.5_70705_1228 ibid, Osepian et al. r.c. C8.8_50510_1152 M1.0_180211_1408 M1.6_160505_908 M2.5_60706_836 X1.1_170704_757 X3.9_170105_952 X1.4_70312_115 LWPM
Nmax height profile from N(t,h): t∆ from X flux 0.1-0.8 nm
How to apply the N(t,h) model to Lyra data ?
Ohshio M, et al. 1966Height distribution of local ionization efficiency,Journal of the Radio Research Laboratories, 13, no 70, 245- 261
Local ionization efficiencies ?
How they change with:
•Wavelength
•Height
from: J.K.Hargreaves,1992, The solar-terrestrial environment
Production rate / irradiance for vertical incidenceat 90 km for 6-20 nm
1210≅k [mJ]
-112
-104
-96
-88
-80
-72
-450
0
450
00:00 04:00 08:00 12:00 16:00 20:00 24:00
10-6
1x10-5
1x10-4
10-3
10-2
10-3
10-20118 UT
0020 UT
0115 UTX1.4
ch2-4(Zr); 6-20 nm + X ray
I [W
/m2 ]
VLF NPM20120307_Casey
ampl
itude
[dB
]
0028 UT p
hase
[deg
]
time UT
0.1-0.8 nm GOES15_20120307
0024 UTX5.4
Ix [
W/m
2 ]
data missing
data missing
2012_03_07
time UT1.2 1.4 1.6 1.8
2× 1011
4× 1011
6× 1011
8× 1011
-120
-100
-80
-600
0
600
00:00 02:00
10-6
1x10-5
1x10-4
10-3
10-2
10-3
10-2
0117.5 UT
0020 UT
0115 UTX1.4
ch2-4(Zr); 6-20 nm + X ray
I [W
/m2 ]
VLF NPM20120307_Casey
ampl
itude
[dB
]
0028 UT p
hase
[deg
]
time UT
0.1-0.8 nm GOES15_20120307
0024 UTX5.4
I x [W
/m2 ]
2012_03_07_0115_X1.4 H=90 km : I(t), N(t) GOES - LYRA
GOES LYRA
Nmax [m-3]: AMP 8.30 ×1011 7.66 × 1011
t(Imax ) UT 0115 0115
(∆t ∆t ′) [min] (2.5, 2.52) (2.5, 2.36)
Nmax [m-3]: PHA 8.82 × 1011
N(t) according to LYRA decreases slower than N(t) according to GOES
N [m-3], I x 1015 [Wm-2]
I x 1014 [Wm-2]
Nmax [m-3]: LWPM 1.13 × 1012
1E-6
1E-5
1E-4
1E-3
-96
-90
-84
-78
-72
-66
00:00 04:00 08:00 12:00 16:00 20:00 24:00
10-3
-450
0
450
0348 UT
I [w
/m-2]
I x
[w/m
-2]
0353 UTM6.3
0.1-0.8 nm GOES15_20120309VLF NPM20120309_Casey
ampl
itude
[dB
]
0357 UT ch2-4(Zr); 6-20 nm + X ray
time UT
pha
se [d
eg]
0349 UT
2012_03_09
5 10 15 20
0.00001
0.00002
0.00003
0.00004
0.00005
0.00006
1.8 1.9 2 2.1 2.2 2.3
1× 10-6
2× 10-6
3× 10-6
4× 10-6
5 10 15 20
0.0015
0.002
0.0025
0.003
0.0035
0.004
1.8 1.9 2 2.1 2.2 2.3 2.4
0.0002
0.0004
0.0006
0.0008
0.001
LYRA ch(2- 4) 6 - 20 nm +XrayLyra peaks at 0201 UT
Irr [W/m2] on 2012_03_09GOES15 0.1- 0.8 nm; 0200 UT_C4.7
Time UT Time UT
1.8 1.9 2 2.1 2.2 2.3
2× 1010
4× 1010
6× 1010
8× 1010
GOES15 LYRA
2012_03_09_0200_C4.7 H=90 km : I(t), N(t)
I scaled 1014I scaled 2 x 1016
1.9 2 2.1 2.2 2.3 2.4
1.2× 1011
1.4× 1011
1.6× 1011
1.8× 1011
2× 1011
Nmax [m-3]: 4.22×1010 1.17× 1011
t(Imax ) UT 0200 0201
t(Nmax ) UT (ev) 2.079 2.08
(∆t ∆t ′) [min] (4.5, 4.6) (3.5, 3.8)
Ns according to both GOES and LYRA peak simultaneously
Time UT Time UT
N [m-3], N [m-3],
Nmax [m-3]: LWPM 3.92 ×1010
X-ray flare ionization is efficient in the range 60-90km, more efficient than any other radiation in the lower D-region.
At the D-region upper limit Ly-Alpha and EUV are mo re efficient.
The diagnostics by Lyra time delay is more approp riate for the D-region upper limit, and is expected to give more realistic N estimates.
Apparently there is no reason to retrieve N from GO ES at 90 km height.But GOES time delay will give more realistic values of N for 74 km height and below.
VLF data A and P give N ( 60- 90 km) independetly o f the particular radiation. A na P bear the integral signature of th e event.
REMARKS
To estimate D- region electron density enhancements during Solar X-ray flares, as diagnostic tools use:
For the lower D-region limit and its vicinity - GOES X-ray data
For the upper D-region limit - LYRA data
For the whole D-region - VLF data
Summary
Thanks to
Proba2 Science Centre
LYRA team Ingolf Dammasch
Antarctica logistic providers