DTIC ADA431710: Monopole-Quadrupole Model of Spacecraft Charging in Sunlight

0.4 MB·English

by  Defense Technical Information Center

Foi Apraved
‘OMB No. 704.0508

REPORT DATE DONA,
Bpeseee

[Tue ane SoerTE—' a conn ORE —
Monopele-Quedrupale Model of Saavecrar:

ic BRANT RI —

[ec PRGGRAN ECERERT TERTBER
= RATIO a PROMECT MUM
MeTaUEE! ana 8. T. bat 502t

“eS ONE

[at RICO ORE ————"
| ERFORUNT ORERUERTN ARERR" |
| 2 ERFORHING GRCANERTION NAMES) AND ADORESEERT PERFORMING ORATION REPORT
Bir Sorze Yosearch sabaratasyenne NUMBER.

29" Kandalph Read
Manson! ANG Sh 02731-3049
AFPI-S-icTR-2005~}003

| * SPONSOR KORTTORBIG RERICY NARETG) ATE RODREESES) pg paps a OHITORE KROHN —|
AERIS |
| Fa¥ORSORNON TORE REFORT
Maas)

é {
7 BaTRTIONT AVATAR SATEEN T
Approved for Public Releater Vistyibuticn Unlimited.

TREE, Ines, Lexington, Mh,

[SL aUPPLERenraRrOTES
REPRINTED PROM TROCHROTNCS

43 Aaa aanosTac

SCTENGHS IRETING aan) RMLBET

10-12 daa 2605, #9, i
Tener —
“ Goophysies rarentch spacceratt are often covered partially wlth thin fayees uf j
ctries such a8 Kuptua or thermal blanket materials, Analytical modeling of the
scharying of a dielecteic spacecraft in saligh code to go Beyond tho monopole
potential and include a dipole lerm. f the capacitancen ofthe dielectric Iqyers ace
suffleientlyTarge aud thu spacecrat spin rats ia sufficiently Last tas patewdals may
bbe determined on tie basis of spin averaged spectra of elestvon an lon tures. Ea
suck a condition the potent) dlsribution resembles that of a mdnopole-
A ‘yuadrupole systen, We formaulute the monapele-quadrupols ease and’ compare iL
(o the monopole-lipale mode. i
[SUE Teme
[Spacecrnf= sharing wanasole-uipole radel sangole-quedmpcle made
[spinuing spscocraft Chania ic. sun. taht
pe seciRYcUsSBICRTION EE E DATATION Te. RAAMHEN 190 ANE DF RESPOTERLEPERSOR|
OFapsimact «= OFeaces | Set ee
= REFORT STSPRBE “| sax. | ie, TELEPHGTE MUTE isa mae]
Tweras acing owas Sn vens

FRR Bee oa
AAA 2068-0088

AFRLVSHATR-20051008
Monopole-Quadrupole Model of Spacecraft Charging in
Sunlight
Moarce Tan"

AED, Ine, Lecinguoa, MA W735
est

Shu. Tit
Space Vehicles Divectorare, Air Hoven Reseaseh Labsrivry, ansoome AB, MA I71.

Geophssles researel spacecraft are often covered parGalty with thin bers of
deterrtee such ae keapton or Herma Wankel materials, Amatytical maleing of
Gurgiog of a dielectric spacecraft in sunlight weeds do yy buyund the manbpale
Polenta sal include w dipole term. I the capacitances of (he dsloeric layers are
Safficienily large aud the spacecraft spin rales slliienty fast the potenglals way
be doterimined on the basis of spin averaged speccra of electron and ion flunss.
sucha condition the poteuthal disteibulion cusemblos that of 2 monopele-
quadzupole system, We formulate the manapole-quadpule ce wale
(the mouapate-dipole mode.

Nommuclature

4 quad upoleUpule ster ela tn emanate

y= svcieients givay De stengC reletve tothe menapils

a ‘monopale potent

Py sf order Tegendie polynenail i
i barrier

Re ‘anni bauer sal

a ‘olentitoutride spacceratt

Fu smusimumn basis heist

Fe anise perential at oP ‘
Pa susface potential at = 99°

% sueliee pote at/— 180° .
Fog = sun o shade potential et

nds

L plemeeanon «0050412 006

angular wieth ot arto:

* Menlo techies AER Jae non, a
jor sosasch PAGED. Ad Tinos evench iron, Aetocise Fela, ATAA,

ait 2808 ne
ATA. 2005-0068

1 Tanednetton

Daylight charging of a aphericl ebjost covaci wits dielectric was far stufiod yy) Maude
sta, Tiegine® aad Besse and Kubin’. “The Laplaoiar.petenialdighibution anand the satelhae is
Tepretented nya eohintion af menqpatc and pale lente, Axial ynumomy aroun The sue directo
fs assumed, an the abject ond he enter stflousey ue ruGaing. The monopole atl dipole ers
combine tw fara a potetial burcisr oulude the sunt raface hich aels to suppress the oscape of
phetactootans,Jeading ultimately ty ence. balance. Tn hi per Aesebe a skit model, wire
ths dipale fore is roplacee hy « quadmpots cowtibucua, Ta the monnpole-quedepole system. the
suiellleapizs about -he por xcs of 3 erpreed obs shining. op the bells-
Ud. Asialssunetsy seoun the spin pule is uae une hae the stl cst be rotating repay
stat only "evolution tne eccraped photoemission is eapsrienced. An arly aymvcciic potential
Darmier ferns al the belly-band to b.ack photasectons, cnebling the uel curent to xh m9 7240, ‘The
pofvatits give the rt order charging reponse in daylight of ara sphricd, wen-condueting, fest
spimmg spaccorat in afow dersiy space else.

To lacie voparison, Une renepolequadrupote ard mpnopule-tipule enalyne mols ate
devalogsd in pallet, Ther: ate to tive puraelers ix tie models. ‘Ihe Hist parawter, K. 18 the
monopole potenlial Tae sevund parsretsr, 4, it the quadripoledipole stg relive 10 the
monopole. ‘Ths basis oqeatio sf dk els aul he parumeters ae doseribod in sti 2, In section
3,auumeruol soliians ure oullned und reruts are piven. Seaton 4 cntins sunmmacy seirarks

11.The Monopaleidipeleiqnadrupole Expansion

The weamicy of pid spies relive to satellite surfs chargig mes, Tete spin perlod ia tong,
compared ta de aiferantial casing tne of dielectric surface elmnets, themurios 9 able to respond
fo ee sim and rte motion tny be conickred slow. fee spin grind is short souaned lo the tee
toles a dieletric surface to barge, the mation keane ka be fist Ta this ease the suiface wuld
Teqpond oat spin avsraged solar Thuniatio,

Consiler a dieletic-covered spherical satelits “rat s rotting enyédly in sight, 0 that only
spin nverayed effect are importa Ifthe mint space change density isle, rahich aaa be Ibe case
at gener chions atin, abe polos’ outside Une aelite word de ger” apptamely by an
axllysyame'sic solution to Laplus'scquarin. th sph cal ceuricalee. che Laplacian potoutisls cat
‘he wrton in tho tw: ace Seer

AF tuo

Fee) o

where ris the mdins and ¢ ia tho polar angle. The sum ig vee 0. 2, 2.-and P41) is Gas 0 order
Logendrs polars. ‘The onpstant coeMiv‘ent Xie the maacpale etn al and he coetacenes dy

lve the stealth relive fo the monopole. Pree ksop tho hues lowest oder Lea, the patria vill,
be

es ey a

where A isd
vn tbe surfnne

pale stengl aud 4s ropresens he quadropole, ars age a wl phere, we have

a

Fil

‘The maanpote-tipale case corresponds © dy a. dU and the menagole quadupule vase v6
specified by dye, 4:54. We net thatthe dns sign i Une amepleaionle earn i arity ana
ALAA-2005-1068

agrees with previous treaimenks pus sgn would per “ken sethe oppose spin pule. ‘The A and 4
patuneters depend op the Bales uf the ‘ncomine and ousgeng steve savtace eMC sae
the amon eres archers nos s5suuted 799 hadi ne ree purumetea of tho minds.

‘The overall shape ofthe potential disibutines eam he soe1 hy Tong at nor, sl aad
south surface pofetiakacthe polarangles 0, 9G snd ISO degrees vemeccvely. hese partial ake
‘Shown bec, with the avon equairsnole sytem on the Teh ans “ie monppole-dipele vase on the
ight, enclose in curly rackets

W,0) = Ny KCN) easeen) a
MIMO) = Vek 4I2 EE oy
PUI) = vs = KO tea) 6

In Cae ecuations, se normely have K «0 for nepative yocage vhuceag sud A % 0 for sunlit,
charging, ‘The raanpole-<qiadmpele system hae eel pore. sl le pule, and loser (negeive
polentil et the bellj-bund. In eaciast, for the mennsnlochpe'e aystem, the polatils ineresse
(egatvely) in going from the nowy 10 sta pul,

‘Te lower fmt on Ar derma hy the chargiog Uaesbule dissnsed in Ube niet section. A
pesatcal upper lant ou 4 ve be taker ar the pea whece the lowe pores ga Jem, This gives
2 1 for tho ronopee-ipo e ryteomand 4=2 fa The mene sole quatre ce,

IL Solution tHe Mindels

Pholuemistion curents(povitive) usualy dormiate amie-t oments ie the magnetuaphere. Yel

negative charging is spot i Gasligh. A roscnansna for sunlight changing 1s well know. Th

shaded surfeves charge up and the Fields wrap apni the: chet se the slit side. A pufeul barier

forms ovtide of the sunt suave fo tap eseuping ponpukeerars, a lowing enrieat hace, Ta

‘models ane bused om this baer dainated soon. Tiina set uation ws le probies: we

saegleclu elF-comsisenl photosteath, whish would xequie Poisar’saquarion ae particle asking
or e potent halite foun, we Lave the cu on

AV eeahide=o a

srl using the revinn expression () for Vet get

A, 2AHO 3g

®

Sowing ‘his eqalion drs gives Ue buerie: radius 2,(4,¢). Hore and oe pve hee Jor a>
senopole-quaciusnle system (the corresponding quaatices for Uke rasmupolecipole mode are
summarized in Tse 8)

Relat

(24nyt «(240 -t0os'9)) ¢

‘A maximum harrisradius, &, oocusat soute angle, Tor he muraronle-quadhupals mov), #8
duesinuu when -P, is al a meximura, hich neours avty= OUP ard vc have Rh, (382492, We
‘an intseprcs tho ange ty ag spocsing lhe ein dinwatine. A beries orm onside the sore Ibe
‘ues abavea shrethold whiot ean be dexrmisd using ths we tion Ry | bc gives A= 25,
AINA, 2005-0068

: on
i | i
bol 16
aol} Boos
gf Cunonurere i
if i
2 aot A 1 8 oe
‘STRENGTH A STRENGTH A

‘thresh oe of

Figure | shows the maximum hervier eos for ae no ols i the eunge of interes. "he hare
reds iniesces moqw'onicelly wit A, fm the “resho‘d vale af ne. ‘he tneximuta cg of Use
tential hair ig gee bye

Pahl ty)-H Le? ‘ny

or the mnie qoutrunle ars, tna a neva

y (y's oe an

A plotot My lr the lwo mudels is given in Vigure 2. The hariers menoteuslly iszteme Fm v0
al he treshld.

‘We cen alr detereime the angular wid, ty. of the bare seginn, given am A-value ahowe
these, The coedition By 1 g-ves he arte ta: snc tho barrier eemao ote suice and ee
ten lh.e), Sulsing Ja the taonopologeadranne cas, ee

0

At deesbuld ay ~ Oud at marin 4 we have ty — 23.1". ‘Swe the muenimune buried “&
less than whe nominal ang with ol putcemission exposwe HAM, we dn not have sel-cousistenl,
photoanissiva dyneaic,

he sunita sade pots sali, Pe, in Che momonole-qracnapae eae given by

Y%y 3)
AIAA-2006 0068

‘SrreNo A a
Fiyoro3. Theson toshade potentialralo Figured, Poloatiuls forthe Monopole.
aca function of strength A for the dipale and Gundenpole system it fhe phine Y=,
‘quadmnpole models, The puramaters ated are te = IT, A ~ OSI.

05. FyEMOIE

which al threshalif is 2.75. A aroparisent
plot of Va is wiven iu Piguee 3. Since Ves
for bath cascs is monotonically decreasing,
The maedsls prediot that this ratio will be
Dbolow the thresh valu,

‘gure 4 shows the aronopole-quad/ pate
poroials, uouuslized tw K. i the phyvil
space eumrnending the aphore. "The cemten plot
showisa Y~ O slice of data enpresond in X.Y, 2
coneinates, vhigh as nemmalized 0 the sphae
radius, The 4 pururcter kas buen releoted 60
thot te barvi petsmual aio Fa # X ~ 001
This sels up u bunier ef 10 V, give a
rmarnapnie poten of <I ¥, An axially
Sninetie polelial buries Foose atthe hell

The cantons plot for the coneepuading
nvaupule-lipole ene is iver. in Fagere 5

Figures. Potential for the Monopole Dipale
system in tho plaae NO, TBe parameter uted
are AT STE, He = L152, Hy —O07

18, Summary

Fora spbeneal fase-ammrg diloctce covered silellite is: i late ina lose deity mbsent
sprce plasm, we have developed u simple avalyee model, “1¢ monapate-quadepals fur aging sn
sunlight ‘The model sets np an axilly aye polente! Eater at te heigrband af de swelite
‘which acts 0 suppress photwemission aru leads eo ewrert balaass. We ean iaterel the made! at
fepeesenting apaceorst charg g with the sum al righ ances lo => spit exis. The Hely-band changes
Jess (negatively) than he apis paler and the an tha potential rai ies boom ib Umsthold vale.
‘The monpoleqiadvupsle ant Ure monopaleinle sytem. are similar in that ey iguore
anany delails of satellite constuction and charging cksiussul in oider to elie he main eects,
A1AA.2005.0068,

or hom, the analysis i tased oa ial Qeumary ad Leplacion polenbels. The major aisrensos
hetween the meds ar: (1) The sun locations aus $0 dees apa ike belly versus the Spm
o!), (2) Uhe charging thresholds are sig "The wu ts shane
ratios ure similar, bus mo the some (Pig= 25 versus V5,

“the mocopole-divele syste the chzk sul is consmlly cen thee the sam dosing, spin
revalusion end thr model fssladss ras alow apia nit, For hs mouapele-quidrupole eystern the
saded side is nstantaneousls changing and. Ue rel exe emly valid for Fast rotation fates, she-e
spin sveznged protosission bsvounes a goed aptosicr ion.

References

'Mondell. M. LKels, G, Selauelle, P. Stees. and. Noche, ‘Ee dacrease m eAere potne
cure dus to sade pom a sleteci pvesils near ill eal charged mpastora, TEE
Frans, Ne: Set, Vol26, No, Bes, 1978, 12121317

“Tigo, D, An analytic mucel of marainscaieel speoserett charging fide an: pera,
WEB Trans, Bh Sc, VOL26, N06, Dus 1978, p 5162

Spense, 8. and A. Rubin, A site analy of spaccoat chore iuvulving Vick photoelectnn
curls. J Genpips. Res. Vol 88, No. AE. 1980, pp.2324-2324

“Remmrare, M. Prnciplr of Recronsnandes,

‘able 1: Comparlarn ofthe Quastrupate verses Dipole Model

Monapole-Quadrupole Madel__ Mfouopale-Diyole Model

R(Aa) 3 a(.-seoe! ‘ij Dhow
rs c
| Ret. we)

*

Anche

oom