Vida Žigman, UNG, Nova Gorica,Slovenia

ESWW10 Antwerp, 18-22 November 2013

Modelling flare induced ionization enhancements of the lower ionosphere with

LYRA data relating Space LYRA – Earth VLF data

Guest Investigator ProgramFourth Call:Sep 2013- Jun 2014

ESWW10 / PROBA2 splinter

Davorka Grubor, UB, Belgrade, Serbia Craig Rodger, Department of Physics, University of

Otago, Dunedin, New ZealandMark Clilverd, British Antarctic Survey, Cambridge,UK

UnderstandImpact of Flares!On the Lower Ionosphere 50-100 km height

• Observations of the effects of Solar X-ray flares from Earth – VLF transmission

• Correlation: VLF data - space based measurements

• Can we exploit LYRA data? • How to combine data and model:

N(t,h), LWPM• (some) RESULTS – 90 km height

• Prospects

OUTLINE Objectives:

DATA:

LYRA ch2-4(Zr); 6 – 20 nm+X-ray(< 2 nm)

(SWAP ?)

GOES 12-15 ( 0.1-0.8 nm ) Flare classification

SPACE : Solar irradiance

GOES

2011_02_28_M1.1

Dammasch et al. 2012COSPAR

Dominique et al. 2013 Solar Physics, DOI: 10.1007.

The LYRA Instrument Onboard PROBA2: Description and In-Flight Performance

Characteristics of the Lyra Irradiance:

•Lyra peaks after GOES •Lyra descends slower than GOES

LYRA - 4 years in orbit

LG

DATA:

EARTH : VLF data - AMPLITUDE & PHASE on different sunlit paths from receivers Rx

• Belgrade IP VLF Observatory – Belgrade University • Casey and Scott Base stations, Antarctica –

Otago University, Dunedin NZ

BAS, Cambridge, UK

raypath

trace

great circle

EARTH

reflection pointD region

Earth-ionosphere

waveguide

T (transmitter)

R (receiver)

Radiowave propagation (Supported by NOSC LWPC)

Solar Lyman Alpha (121.6 nm)

during flares: Solar X-rays

emitVLF

f < 30 kHz

Transmitter:NWC/19.8 kHz

Receiver:Belgrade AbsPAL

On Earth:

D-region

measureAMPLITUDE

& PHASEDISTURBANCES

2011_02_18 NWC - Bgd

06:00 07:00 08:00 09:00 10:00 11:00

10-5

10-4

10-3

1E-8

1E-7

1E-6

1E-5

1E-4

1E-3

I X

[W

/m2 ]

Lyr

a I[

W/m

2 ]

time UT

NWC-Bgd 20110218

40

50

60

70

ampl

itude

[dB

]

0

350

700

phas

e [d

eg]

M6.6C4.2C8.5 C7.6

OBSERVATIONS:

All data in

1 min cadence

NWC – Bgd

11974 km

q( t ) = k I (t)

2Nqdt

dN

1

1

)1(2

dt

dNN

q

dt

dN

MODELLING:

time dependence!

-50

-40

00:00 04:48

10-6

1x10-5

1x10-4

10-3

10-2

0

10-3

10-2

I X [W

/m2 ]

I [W

/m2 ]

NPM20120307_SCOTT BASE

0028 UTLYRA ch2-4(Zr); 6-20 nm + X ray

GOES15 0.1-0.8 nm

0024 UT_X5.4

time UT

01:15.478 UT; 1.37E-4

Irradiance I (t) 2012_03_07

FROM LYRA!

From Goes

)()( maxmax ItNttttmaxmax IPA,

AMP & PHA Time delay!

4.0x10-4

8.0x10-4

1.2x10-3

1.6x10-3

2.0x10-3

20:40 20:50 21:00 21:10 21:20 21:30 21:4010-7

10-6

1x10-5

1x10-4

0

100

200

300

400

500

2057_M1.5

I L (

W/m

2 )ph

ase

(d

eg

)

-44

-42

-40

-38

-36

-34

am

plit

ud

e (

dB

)

time UT

I x (W

/m2 )

NPM_SB_20131028_2057_M1.5

10 10.1 10.2 10.3

1 1011

2 1011

3 1011

4 1011

5 1011

6 1011

7 1011

N [

m-3],

I X

x 1

016 ,

I L x

1014

[W

m-2]

Time UT

Electron density at 90 km height from AMPLITUDE time delay

)',( AA tt 4.14 1011 GOES (2, 1.92)1.74 1011 LYRA (1, 0.79)

Nmax [m-3]

LYRA Imax 1012 UT , 3.35 mW/m2

min1LG

[min]

NWC- Bgd 20110218_1011_M6.6

10:00

10-5

10-4

10-3

1E-8

1E-7

1E-6

1E-5

1E-4

1E-3

I X

[W

/m2 ]

Lyr

a I[

W/m

2 ]

time UT

NWC-Bgd 20110218

40

50

60

70

ampl

itude

[dB

]

0

400

phas

e [d

eg]

1013

2013_05_13 NPM – Scott BaseOBSERVATIONS:

00:00 04:00 08:00 12:00 16:00 20:00 24:00

10-4

10-3

10-2

1E-6

1E-5

1E-4

C8.3X1.7

2205 UT

X2.8C9.3

( Ix

GO

ES W

/m2 )

2207 UT

2209 UT

(Ix

Lyr

a W

/m2 )

LYRA_ 20130513

time UT

2207 UT

-75

-70

-65

-60

-55

-50

-45

-40

-35

-30

-25

-20

-15

ampl

itude

(dB

)

NPM-SB 20130513-1200

-800

-400

0

400

800

phas

e (d

eg)

(M1.3)

Lll

L

Scott

Gde je NPM?

Casey Scott B.

NWC/19.8 kHz

NPM/21.4 kHz

NPM- Scott Base

11260 km

-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

10-2

0118 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

[de

g]

time UT

0.1-0.8 nm GOES15_20120307

0024 UTX5.4

Ix

[W/m

2 ]

data missing

data missing

2012_03_07_ NPM-Casey

-70

-60

-50

-40

00:00 04:00 08:00 12:00 16:00 20:00 24:00

10-6

1x10-5

1x10-4

10-3

10-2

-2000

-1000

0

10-4

10-3

10-2

10-1

I X [

W/m

2 ]

I [W

/m2 ]

NPM20120307_SCOTT BASE

Tx out of order

0.1-0.8 nm GOES15_20120307 0024_X5.4

time UT

PH

A [

deg]

AM

P [

dBm

]

01:15.478 UT; 1.37E-4

00:11.496 UT 00:19.5 UT01:15.498 UT

data missing

2012_03_07_ NPM-Scott Base

1.2 1.4 1.6 1.8

2 1011

4 1011

6 1011

8 1011

1 1012

N [

m-3],

I X

x 1

015 ,

I L x

1014

[W

m-2]

Time UT

-100

-80

-600

0

600

00:00 04:48

10-6

1x10-5

1x10-4

10-3

10-2

10-3

10-2

0115 UT

0118 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

pha

se [

deg]

time UT

GOES15 0.1-0.8 nm

0024 UTX5.4 I

x [W

/m2 ]

-50

-40

00:00 04:48

10-6

1x10-5

1x10-4

10-3

10-2

0

10-3

10-2

I X [

W/m

2 ]

I [W

/m2 ]

NPM20120307_SCOTT BASE

0028 UTLYRA ch2-4(Zr); 6-20 nm + X ray

GOES15 0.1-0.8 nm

0024 UT_X5.4

time UT

PH

A [

deg]

AM

P [

dBm

]

20120307_0115_ NPM-Casey X1.4 NPM_Scott Base - - - - - - - - - - - -

)5.3,5.2(

min),( PA tt

maxN

(7.4 1011, 1012) m-3

Overall: at 90 km

LG0

10-4

10-3

00:00 04:00 08:00 12:00 16:00 20:00 24:0010-9

10-8

10-7

10-6

1x10-5

1x10-4

M4

.4M

2.7

M2

.8

M1.4C5.2M5.1X1.02057_M1.5

I (W

/m2 )

day

NPM-SB 20131028

time UT

Ix (

W/m

2 )

-60

-45

-30a

mp

litu

de

(d

B)

-600

-400

-200

0

200

400

ph

ase

(d

eg

)

2013_10_28_ NPM-Scott Base

20.9 21 21.1 21.2 21.3

2.5 1010

5 1010

7.5 1010

1 1011

1.25 1011

1.5 1011

1.75 1011

N [

m-3],

I X

x 1

016 ,

I L x

1014

[W

m-2]

Time UT

NPM-Scott Base 20131028_2057_M1.5Electron density at 90 km height from AMPLITUDE & PHASE time delay

7.36 1010 GOES (2.5, 2.32)3.89 1010 LYRA (0.5, 0.52)

AMP

9.76 1010 GOES (3.5, 3.30)1.05 1011 LYRA (1.5, 1.58)

PHA

min2LG

LYRA Imax 2059 UT , 1.78 mW/m2

Nmax [m-3] )',( tt [min]

4.0x10-4

8.0x10-4

1.2x10-3

1.6x10-3

2.0x10-3

20:40 20:50 21:00 21:10 21:20 21:30 21:4010-7

10-6

1x10-5

1x10-4

0

100

200

300

400

500

2057_M1.5

I L (

W/m

2 )ph

ase

(d

eg

)

-44

-42

-40

-38

-36

-34

am

plit

ud

e (

dB

)

time UT

I x (W

/m2 )

Summary • LYRA data can be used to assess the flare enhanced electron density at the ceiling of the D-region - 90 km.

Nmax, N(t) • N(t) according to LYRA decreases slower than according to

GOES.• The predictions of the maximal flare induced electron density at 90 km height are in reasonabe agreement.

M1.5 M6.6 X1.4 Nmax [m.3] (7.4 1010, 1011) 2 - 4 1011 (7.5 1011, 1012)

Prospects: • Can the lower ionization efficiency be compensated by higher irradiance ?

• Assessment with Long Wavelength Propagation Capability LWPC (NOSC)

Thanks to

Proba2 Science Centre D. Berghmans

M. Dominique LYRA Team M. West

NOAA/SWPC

Antarctica logistic providers

The Audience !

ESWW10 Antwerp, 18-22 November 2013