Space Radiation and its Effects on EEE Components

**on****on** **EEE** Comp**on**ents

Marc Poizat

ESA/ESTEC

TEC-QEC

**on**ment

EPFL

**on****on** **EEE** Comp**on**ents

Course Outline

• The Earth’s Trapped **on**

• Solar Particles

• Galactic Cosmic Rays

• Interacti**on**s of radiati**on** particles with

electr**on**ic devices

• Top level space envir**on**ment requirements

• Calculati**on** methods

EPFL

**on****on** **EEE** Comp**on**ents

Galactic

cosmic rays

Neutrinos

EPFL

Solar

X-rays

Solar flare

neutr**on**s

Sec**on**dary

emissi**on**s

Anomalous

cosmic rays

Trapped

particles

Jovian

electr**on**s

Solar event prot**on**s,

heavy i**on**s, **on**s

**on****on** **EEE** Comp**on**ents

The magnetosphere : a natural shield

EPFL

**on****on** **EEE** Comp**on**ents

Course Outline

• The Earth’s Trapped **on**

• Solar Particles

• Galactic Cosmic Rays

• Interacti**on**s of radiati**on** particles with

electr**on**ic devices

• Top level space envir**on**ment requirements

• Calculati**on** methods

EPFL

**on****on** **EEE** Comp**on**ents

The trapped radiati**on** belts

• Van Allen belts. Discovered during first space missi**on**s.

EPFL

**on****on** **EEE** Comp**on**ents

The trapped radiati**on** belts = dynamic envir**on**ment

EPFL

**on****on** **EEE** Comp**on**ents

The Trapped **on****on**ment (1)

• Inner belt is dominated by a populati**on** of energetic prot**on**s up

to ~400 MeV energy range

– Product of Cosmic-Ray Neutr**on** Decay

– Inner edge is encountered as the South Atlantic Anomaly

(SAA)

– Dominates the **on**

envir**on**ments

• Outer Belt is dominated by a populati**on** of energetic electr**on**s

up to 7 MeV;

– Frequent injecti**on**s

– Dominates the geostati**on**ary orbit envir**on**ment (mostly

telecom) **on** (Galileo, GPS) orb

certain Science missi**on**s in highly elliptic orb

Newt**on**, INTEGRAL)

EPFL

**on****on** **EEE** Comp**on**ents

The Trapped **on****on**ment (2)

• Trapped Electr**on**s (AE8 model) - Trapped Prot**on**s (AP8 model)

• AE8 **on** **on** spectra at solar

Minimum

• But envir**on**ment dynamic

EPFL

**on****on** **EEE** Comp**on**ents

The Trapped **on****on**ment (3)

• Moti**on** of a charged particle in the radiati**on** belts: triple

moti**on**.

EPFL

**on****on** **EEE** Comp**on**ents

The Trapped **on****on**ment (4)

• The South Atlantic Anomaly

EPFL

UoSAT SEUs

**on****on** **EEE** Comp**on**ents

The Trapped **on****on**ment (5)

EPFL

**on****on** **EEE** Comp**on**ents

The Trapped **on****on**ment (6)

EPFL

**on****on** **EEE** Comp**on**ents

The Trapped **on****on**ment (7)

EPFL

**on****on** **EEE** Comp**on**ents

Course Outline

• The Earth’s Trapped **on**

• Solar Particles

• Galactic Cosmic Rays

• Interacti**on**s of radiati**on** particles with

electr**on**ic devices

• Top level space envir**on**ment requirements

• Calculati**on** methods

EPFL

**on****on** **EEE** Comp**on**ents

Solar Particles (1)

� Solar Events of October – November 2003.

Images from the SOHO

EPFL

**on****on** **EEE** Comp**on**ents

Solar Particles (2)

� **on**

� Solar activity cycle approximately 11 years l**on**g

� Fluences high enough to cause damage => importance

of proper shielding

� Include prot**on**s **on**s

� Energy spectrum highly variable

� Essentially unpredictable, however efforts dedicated to

address the problem in various

� Analysis methods are statistical (e.g. ESP, JPL-91,

models, available in SPENVIS, OMERE)

� Solar particles are shielded by the Earth magnetic field

EPFL

**on****on** **EEE** Comp**on**ents

Solar Particles (3)

• STS-116 missi**on** to ISS

EPFL

Flux (1/cm2/sr/s)

1E+03

1E+02

1E+01

1E+00

1E-01

1E-02

SPEs of December 2006 (GOES)

>10 MeV

>50 MeV

>100 MeV

STS-116 spacewalk 1

STS-116 spacewalk 2

11/12 12:00 12/12 00:00 12/12 12:00 13/12 00:00 13/12 12:00 14/12 00:00 14/12 12:00 15/12 00:00 15/12 12:00 16/12 00:00

**on****on** **EEE** Comp**on**ents

Course Outline

• The Earth’s Trapped **on**

• Solar Particles

• Galactic Cosmic Rays

• Interacti**on**s of radiati**on** particles with

electr**on**ic devices

• Top level space envir**on**ment requirements

• Calculati**on** methods

EPFL

**on****on** **EEE** Comp**on**ents

Galactic Cosmic Rays (1)

� Flux ~ 4 particles /cm 2 /sec in space, anticorrelati**on** with solar activity

� Atmosphere shields Earth’s surface from “primary" cosmic rays

� Collisi**on**s in upper atmosphere produce "sec**on**dary" cosmic rays

- some reach ground level (seen in “neutr**on** m**on**itors”)

� Average pers**on** is crossed by ~ 100 relativistic mu**on**s per sec**on**d

� Discovered in 1912 by Austrian Victor Hess

� Supernovae produce high energy cosmic rays, accelerated by

moving shocks, as suggested by Enrico Fermi in 1949.

� Charged particles accelerated to near speed of light

( can reach ~10 20 eV range. The most powerful particle accelerators

**on** Earth “weak” in comparis**on**)

� Most accurate GCR model is CREME96 by NRL.

EPFL

**on****on** **EEE** Comp**on**ents

Galactic Cosmic Rays (2)

• Anticorrelati**on** with solar min/max periods

EPFL

**on****on** **EEE** Comp**on**ents

• Compositi**on**

Galactic Cosmic Rays (3)

EPFL

**on****on** **EEE** Comp**on**ents

Course Outline

• The Earth’s Trapped **on**

• Solar Particles

• Galactic Cosmic Rays

• Interacti**on**s of radiati**on** particles with

electr**on**ic devices

• Top level space envir**on**ment requirements

• Calculati**on** methods

EPFL

**on****on** **EEE** Comp**on**ents

Interacti**on** of **on**

Electr**on**ic Devices

The effects of radiati**on** **on** electr**on**ic devices

depend **on** :

• Type of radiati**on** (phot**on**, electr**on**, prot**on**...)

• Rate of interacti**on**

• Type of material (Silic**on**, GaAs..)

• Comp**on**ent related (process, structure, etc.)

C**on**sequences : I**on**izati**on** (TID

Displacement Damage

EPFL

**on****on** **EEE** Comp**on**ents

Interacti**on** of **on**

Electr**on**ic Devices

• Electr**on**-matter interacti**on**:

– N**on** linear trajectory

– Bremsstrahlung producti**on**

– 1D shielding analysis with

Shieldose or Mulassis

– Interacti**on**s best described

by M**on**te Carlo analysis (GEANT4)

– Range in Al:

• R(cm) = 0.196E (MeV) – 0.04

(for 1 < E < 20 MeV i.e. for E = 5MeV, R = 9cm)

EPFL

**on****on** **EEE** Comp**on**ents

Interacti**on** of **on**

Electr**on**ic Devices

• Prot**on**-matter interacti**on**:

– Linear trajectory

– Energy loss via direct **on**izati**on**

– Spallati**on** reacti**on**s for E > 10 MeV

– Range in Al: R(cm) = 10 -3 .E 1.74 (MeV)

For E = 7MeV, R = 0.3mm

For E = 100MeV, R = 3cm

For E = 1GeV, R = 160cm

EPFL

**on****on** **EEE** Comp**on**ents

Interacti**on** of **on**

Electr**on**ic Devices

• Heavy i**on** – matter interacti**on**:

– Essentially same as with prot**on** except much higher

energies involved

EPFL

**on****on** **EEE** Comp**on**ents

Interacti**on** of **on****on**ic

Devices

• Particles causing Single Events

– Galactic cosmic rays

– Cosmic solar particles (heavily influenced by solar flares)

– Trapped prot**on**s in radiati**on** belts

• Particles causing l**on**g term degradati**on** radiati**on** damage

– Trapped electr**on**s in radiati**on** belts (TID)

– Trapped prot**on**s in radiati**on** belts (TID, Displacement damage)

– Prot**on**s from solar flares

EPFL

**on****on** **EEE** Comp**on**ents

Course Outline

• The Earth’s Trapped **on**

• Solar Particles

• Galactic Cosmic Rays

• Interacti**on**s of radiati**on** particles with

electr**on**ic devices

• Top level space envir**on**ment requirements

• Calculati**on** methods

EPFL

**on****on** **EEE** Comp**on**ents

Calculating total i**on**izing dose

• SHIELDOSE2 (from Seltzer) calculates electr**on** **on** doses

for Al planar

AsGa…)

• Can be generated by M**on**teCarlo.

• Inputs necessary to generate Total I**on**izing Dose curves are

electr**on** **on**s fluxes (integral or differential)

• SHIELDOSE implemented in SPENVIS

EPFL

**on****on** **EEE** Comp**on**ents

Sector Analysis - Geometries

EPFL

**on****on** **EEE** Comp**on**ents

Dose depth curve for a 5 year LEO polar missi**on**

(800km, 98deg)

EPFL

**on****on** **EEE** Comp**on**ents

Dose rate al**on**g LEO polar orbit

EPFL

**on****on** **EEE** Comp**on**ents

Dose depth curve for a 15 year Navigati**on** (Galileo, GPS)

missi**on** (23000km, 56deg)

EPFL

**on****on** **EEE** Comp**on**ents

Dose depth curve for an 18 year geostati**on**ary missi**on**

(36000km, 0deg, 160W)

EPFL

**on****on** **EEE** Comp**on**ents

Displacement damage calculati**on**

• Device degradati**on** due to displacement damage can be

evaluated thanks to NIEL (MeV.cm2/mg)

• If NIEL curve for a given material is known (Si, GaAs…), calculate

Displacement Damage Equivalent Fluence (DDEF):

Φ

10

1

=

⋅

NIEL(

10MeV

)

MeV ∫

• DDEF at part level can be either calculated by sector analysis or

M**on**teCarlo

• If NIEL curve not available in litterature, possibility if using NEMO

(NIEL Evaluati**on** Model of ONERA). NEMO is a Geant4 based

tool implemented in OMERE.

EPFL

Φ(

E)

⋅NIEL(

E)

**on****on** **EEE** Comp**on**ents

DDEF depth curve for a 5 year LEO missi**on**

(800km, 98deg)

EPFL

**on****on** **EEE** Comp**on**ents

DDEF depth curve for a 15 year Navigati**on** (Galileo, GPS)

missi**on** (23000km, 56deg)

EPFL

**on****on** **EEE** Comp**on**ents

DDEF depth curve for an 18 year geostati**on**ary missi**on**

(36000km, 0deg, 160W)

EPFL

**on****on** **EEE** Comp**on**ents

LET spectrum

• To study the effects of GCR in microcircu

heavy i**on**s are comm**on**ly described by amount of

energy lost per unit track length i.e. Linear Energy

Transfer

• Linear Energy Transfer (LET)

– Energy loss per unit path length

– dE/dx = MeV/cm

– Divide by material density = MeV-cm 2 /mg

– LET of 97 MeV-cm 2 /mg corresp**on**ds to charge

depositi**on** of 1pC/μm

• How does LET spectrum relate to the real space

envir**on**ment?

EPFL

**on****on** **EEE** Comp**on**ents

LET (MeV-cm 2 /mg)

110

100

90

80

70

60

50

40

30

20

10

LET vs. Energy

0

0.1 1.0 10.0 100.0 1000.0 10000.0 100000.0

Energy (MeV/u)

EPFL

H

He

Li

Fe

Ni

Te

I

Au

Pb

U

After J. Barth, 1997 NSREC Short course

**on****on** **EEE** Comp**on**ents

Fluence (#/cm 2 )

GCR **on**ment vs. LET

10 4

10 3

10 2

10 1

10 0

10 -1

10 -2

10 -3

10 -4

10 -5

10 -6

10 -7

10 -8

200 mils

10

0.1 1.0 10.0 100.0

-9

LET (MeV-cm 2 /mg)

EPFL

Total

H

He

Li

Mg

Fe

Ni

I

Au

Pb

U

After J. Barth, 1997 NSREC Short course

**on****on** **EEE** Comp**on**ents

Fluence (#/cm 2 /s)

SPE **on**ment vs. LET

10 3

10 2

10 1

10 0

10 -1

10 -2

10 -3

10 -4

10 -5

10 -6

10 -7

10 -8

10 -9

10 -10

10 -11

10 -12

200 mils

10

0.1 1.0 10.0 100.0

-13

EPFL

LET (MeV-cm 2 /mg)

Total

H

He

Li

Mg

Fe

Ni

I

Au

Pb

U

After J. Barth, 1997 NSREC Short course

**on****on** **EEE** Comp**on**ents

Fe/cm 2 /s/MeV/n

**on****on**ment - Fe

10 3

10 2

10 1

10 0

10 -1

10 -2

10 -3

10 -4

10 -5

10 -6

10 -7

10 -8

10 -9

10 -10

10 -11

0.1 1.0 10.0 100.0 1000.0 10000.0 100000.0

30

0

0.1 1.0 10.0 100.0 1000.0 10000.0 100000.0

Energy (MeV/u)

EPFL

GCR

Solar peak Peak

LET

20

10

LET (MeV-cm 2 /mg)

After J. Barth, 1997 NSREC Short course

**on****on** **EEE** Comp**on**ents

LET

LET (MeVcm 2 /mg)

40

30

20

10

0

10 -2

10 -1

10 0

10 1

Energy (MeV/u)

EPFL

10 2

10 3

10 4

10 6

10 5

10 4

10 3

10 2

10 1

10 0

After J. Barth, 1997 NSREC Short course

range (um)

**on****on** **EEE** Comp**on**ents

Pb/cm 2 /s/MeV/u

**on****on**ment - Pb

10 -3

10 -4

10 -5

10 -6

10 -7

10 -8

10 -9

10 -10

10 -11

10 -12

10 -13

10 -14

10 -15

10 -16

10 -17

0.1 1.0 10.0 100.0 1000.0 10000.0 100000.0

100

0

0.1 1.0 10.0 100.0 1000.0 10000.0 100000.0

Energy (MeV/u)

EPFL

GCR

Solar Peak

LET

90

80

70

60

50

40

30

20

10

de_dx

LET (MeV-cm 2 /mg)

After J. Barth, 1997 NSREC Short course

**on****on** **EEE** Comp**on**ents

Testing to the Envir**on**ment - GCR

LET Fluence (#/cm 2 /day)

f_all

10 -1

10 -2

10 -3

10 -4

10 -5

10 -6

10 -7

10 -8

10 -9

10 -10

10 -11

10 -12

10 -13

10 -14

200 mils

Total Integral LET Spectra

10

0.1 1.0 10.0 100.0

let_all

-15

EPFL

LET (MeV-cm 2 /mg)

for E > 0.1 MeV/n

for E > 25 M eV/n

for E > 200 MeV/n

After J. Barth, 1997 NSREC Short course

**on****on** **EEE** Comp**on**ents

Testing to the Envir**on**ment - Solar

LET Fluence (#/cm 2 /s)

f_all

10 3

10 2

10 1

10 -1

10 0

10 -2

10 -3

10 -4

10 -5

10 -6

10 -10

10 -9

10 -8

10 -7

10 -11

10 -12

10 -13

10 -14

200 mils

Total Integral LET Spectra

10

0.1 1.0 10.0 100.0

e_all

-15

EPFL

LET (MeV-cm 2 /mg)

for E > 0.1 MeV/n

for E > 25 MeV /n

for E >200 M eV /n

After J. Barth, 1997 NSREC Short course

**on****on** **EEE** Comp**on**ents

Fluence (#/cm 2 /s)

10 6

10 5

10 4

10 3

10 2

10 1

10 0

10 -1

10 -2

10 -3

10 -4

10 -5

10 -6

10 -7

10 -8

10 -9

10 -10

Direct I**on**izati**on** by Prot**on**s

0.01 0.10 1.00 10.00 100.00 1000.00 10000.00 100000.00

0.6

GCR Surface

GCR 200 mils

GCR 500 mils

Solar Peak Surface

Solar Peak 200 mils

Solar Peak 500 mils

0.5

LET E >0.1 MeV

LET E > .01 MeV 0.4

0.0

0.01 0.10 1.00 10.00 100.00 1000.00 10000.00 100000.00

Energy (MeV)

EPFL

0.3

0.2

0.1

let_reg2

LET (MeV-cm 2 -mg)

After J. Barth, 1997 NSREC Short course

**on****on** **EEE** Comp**on**ents

LET Fluence (#/cm 2 /s)

f_reg

10 -5

10 -4

10 -3

10 -2

10 -1

10 0

10 1

10 2

10 3

10 4

10 5

10 6

Low LET Prot**on**s

Total Integral LET Spectra

10

0.001 0.010 0.100

let_reg

1.000 10.000 100.000

-14

10 -13

10 -12

10 -11

10 -10

10 -9

10 -8

10 -7

10 -6

200 mils

EPFL

LET (MeV-cm 2 /mg)

GCR

Solar Peak

GCR

Solar Peak

After J. Barth, 1997 NSREC Short course

**on****on** **EEE** Comp**on**ents

Course Outline

• The Earth’s Trapped **on**

• Solar Particles

• Galactic Cosmic Rays

• Interacti**on**s of radiati**on** particles with

electr**on**ic devices

• Top level space envir**on**ment requirements

• Calculati**on** methods - Tools

EPFL

**on****on** **EEE** Comp**on**ents

Predicting the radiati**on** envir**on**ment at

comp**on**ent level

• Several methods to calculate received I**on**izing Dose or N**on**-i**on**izing

dose at part level:

– 3D M**on**teCarlo. Can be either direct (GEANT4) or reverse (e.g. NOVICE)

M**on**teCarlo. Huge computing time with GEANT4 (up to several m**on**ths).

Requires prot**on** **on** spectra as inputs. For displacement damage,

NIEL curve in the appropriate target material also necessary.

– Sector analysis. Less accurate but quick **EEE** parts.

Requires Total I**on**izing dose curve or Total N**on** I**on**izing dose curve as inputs

– The more complex the geometry of the CAD model, the higher the computing

time.

• Heavy i**on** **on** induced SEE rates calculated with CRÈME96

(creme96.nrl.navy.mil/).

CREME86 available in OMERE

– Inputs necessary to calculate SEE rates are Intergral LET spectrum

device cross secti**on**.

– Calculati**on**s performed **on**ly with simple shielding geometries

EPFL

**on****on** **EEE** Comp**on**ents

TID, TNID computer methods for particle

transport

Vehicle

geometry

specificati**on**

**on**

transport

data

Missi**on** specificati**on**

Compute charged particle

positi**on**al

orbit-averaged

missi**on**-averaged

flux-vs-energy spectra

Flux spectra

Simple-geometry

radiati**on** transport

**on**

Dose-depth curve

Solid-angle

sectoring

Dose at a point

EPFL

Particle

envir**on**ment

models

Materials

geometry specificati**on**

Complex-geometry

radiati**on** transport

**on**

(M**on**te Carlo)

Geomagnetic

field models

**on**

transport

data

After Daly, ESA report 1989

**on****on** **EEE** Comp**on**ents

Sector Analysis - Definiti**on**

• Based **on** “straight ahead” approximati**on**

• 4π space around the detector is divided into

N elementary solid angles ω i

• Calculate the dose d i for each elementary

solid angle by using dose depth curve

• Sum the c**on**tributi**on** of all the sectors:

N 1

D = 4π

N

∑

i=

1

EPFL

⋅

d

i

⋅

ωi

**on****on** **EEE** Comp**on**ents

Ray tracing paths

• Norm method Slant method

r

r

• Norm method to be used in c**on**juncti**on**

with Shell sphere dose curve

method with solid sphere dose curve

EPFL

r

r

α

**on****on** **EEE** Comp**on**ents

Sector analysis

• Simple or detailed sectoring analysis

– Influence of material type is neglected. Different materials are approximated to equivalent

mass of a single material type (typically Al) by a proporti**on**al change in density.

– The sector shielding approach does not c**on**sider the physics involved in the

• performance of graded shields, dose enhancement,

• or in calculating the X-ray bremsstrahlung dose in a locati**on** shielded by tantalum

– Sectoring is not appropriate for the assessment of sec**on**dary hadr**on** levels from materials

with significantly different atomic mass number from the original target material.

– For electr**on** dominated orb**on**), sector/ray tracing analysis can

overestimate or (sometimes) underestimate the dose levels.

– For prot**on** dominated orb**on** of the dose level.

• Example Sectoring Analysis tools

– Fastrad

– ESABase

– SSAT (capable of implementing Geant4 geometry)

EPFL

**on****on** **EEE** Comp**on**ents

Examples of sector analysis tools

EPFL

**on****on** **EEE** Comp**on**ents

Missi**on** Dose (krad(Si))

35

30

25

20

15

10

5

0

TID at part level – ST5

200-35790km, 0 degree inclinati**on**, 3 m**on**ths

C&DH_A1

C&DH_A3

C&DH_A5

C&DH_B2

C&DH_B4

HPA_A1

HPA_A3

HPA_A5

HPA_B2

HPA_B4

MSSS_B1

MSSS_C1

MSSS_C3

MSSS_C5

MAG_ELEC_2

MAG_ELEC_4

PRESS_SENS

PSE_A2

PSE_A4

PSE_B1

PSE_B3

PSE_B5

VEC_CON1_2

VEC_CON1_4

VEC_CON2_1

VEC_CON2_3

VEC_CON2_5

Subsystem dose point

EPFL

An accurate spacecraft model

will increase the accuracy of

dose requirements

Top Level Requirement

XPOND_A2

XPOND_A4

XPOND_B2

XPOND_B4

XPOND_C2

XPOND_C4

**on****on** **EEE** Comp**on**ents

M**on**te Carlo Particle Transport

• Detailed radiati**on** “transport” calculati**on**s provide a more accurate

treatment of the radiati**on** interacti**on** processes. Calculates:

– particle numbers, species, energy, **on** of propagati**on**

• MC required when accurate part level dose calculati**on** necessary.

• MC Calculati**on**s based **on** the actual material employed

• MC calculati**on**s also include sec**on**dary particle informati**on**

• Example MC tools

– Geant4 based tools

– NOVICE

– MCNPX (limited accessibility)

EPFL

Geant4 simulati**on** of ISS ATV module

**on****on** **EEE** Comp**on**ents

C**on**clusi**on**

• Defining the space radiati**on** envir**on**ment is an

essential input to cope with radiati**on** effects in

**EEE** comp**on**ents during space missi**on**s.

• Numerous future challenges:

– Need for updated, more accurate

models taking into account e.g. solar cycle activity

variati**on**s…

– Better predicti**on**s of space weather is essential for

future manned missi**on**s to the Mo**on**

– Improved models would help produce more reliable

implementati**on** of new space technologies

EPFL

**on****on** **EEE** Comp**on**ents

References

• I**EEE** NSREC Short courses

• RADECS Short courses

• ECSS-E-10-04

• The near-Earth **on**

Envir**on**ment, S. Bourdarie et. al., I**EEE**

Trans. Nucl. Sci., Vol. 55, No. 4, Aug.

2008

• www.spenvis.be

• http://trad.fr/OMERE-Software

EPFL