Department of Astronomy Annual Report 2000

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University of Helsinki

Annual Report 2000

Observatory P.O. Box 14, FIN-00014 University of Helsinki, Finland

http://www.astro.helsinki./

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Thepastyearwasaneventful oneforthe Observa-

tory. InJanuary2000,theFacultyofScienceinitiateda

processaimedatamergeroftheObservatoryintoaDe-

partmentofPhysicalSciences,whichwastobefounded.

Followingawholeyear'swork lledwith reports,meet-

ings,appeals,etc.,theFacultyofSciencedecidedonDe-

cember14th,2000that theDepartmentsofAstronomy,

Geophysics, Meteorology and Physics shall be merged

into one large institute. On January 17th, 2001, the

Senate of the University of Helsinki decided, however,

that the Department of Astronomy shall remain inde-

pendent, while the former Departments of Geophysics,

Meteorology and Physics will begin to operate at the

Kumpula Campus as the new Department of Physical

Sciencesfrom August1st,2001onwards.

Regardlessofthenal positiveoutcomeofthis\ad-

ministrativeadventure",thepastyear2000wasextreme-

ly demanding for the Observatory sta and students.

Fortunately, wecannowagain concentrateonourfore-

most duties which remain the researchand teaching of

Astronomy. Theboard oftheObservatoryhasdoneits

bestto secure thatthese dutiesare performed. I thank

theboard fortheirsupport.

Asforthenextyears,Iwishthatwemaypeacefully

concentrateonourwork,andthattheadministrationof

theUniversitywouldgiveussuÆcientresourcesforthis.

The fact that the fraction of external funding reached

80% in our last year's budget, already provesby itself

that the Observatory sta has performed high quality

research. Mydenition ofafullyoperativeObservatory

isthattheannualvolumeofourresearchremainsatthe

levelofat least40refereedpapers,andthattheannual

numberof completedM.Sc. degrees risesto 3from the

current mean value of 1 1

6

, while the number of Ph.D.

degrees remains at the steady level of one or two per

year.

LauriJetsu

DirectoroftheObservatory

Helsinki,June11th,2001

1 Strategy ofthe Observatory 1

2 Research of interstellar medium and star for-

mation 2

2.1 Researchactivities . . . 2

2.2 Progress . . . 2

2.2.1 Recentworkandachievements . . . . 2

2.3 Moneyandresources . . . 3

2.4 Testsoflearning . . . 3

2.5 Visitsabroad . . . 3

2.6 Visitingacademics . . . 4

2.7 Papersreadatscienticconferences,symposia, meetingsetc. . . 4

2.8 Membershipinscienticandscholarlysocieties 5 2.9 Acting as Opponentand pre-examinationsof doctoraldissertations. . . 5

2.10 Additionalinformation . . . 5

3 Planetary Astronomy 6 3.1 Researchactivities . . . 6

4 High EnergyAstrophysics 7 4.1 Researchactivities . . . 7

4.4 Testsoflearning . . . 8

4.8 Membershipinscienticandscholarlysocieties 9 4.9 Additionalinformation . . . 9

5 Stellar-planetary Astronomy 10 5.1 Researchactivities . . . 10

5.2 Progress . . . 10

5.7 Membershipinscienticandscholarlysocieties 13 5.8 Additionalinformation . . . 13

6 Publications 14 6.1 Scienticmonographies . . . 14

6.2 Articlesinrefereedjournals . . . 14

6.3 Otherrefereedarticles . . . 15

7 Academicdegreesbetween1995 and2000 16

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In order to guarantee the developmentof astronomical

research and teaching in the University of Helsinki, we

aimforhighqualityresearchinthoseeldsofAstronomy

that are pursued by thefour researchgroups currently

workingattheObservatory. Thechosenstrategicmeans

are:

Participationinlargescienticprojects:Highqual-

ityresearchrequiresaccesstothebestexistingin-

struments. The membership in international or-

ganizations oers this advantage. The Observa-

toryisactivelyinvolvedinseveralESA(European

SpaceAgency)projects,suchasISO,INTEGRAL,

SMART-1 andPlanck. Wearelookingforwardto

thenew resources oeredby the imminent mem-

bership of Finland in ESO (European Southern

Observatory). Among our ongoing joint research

projectsare,e.g. theuseofSwedish-ESOSubmil-

limetreTelescope (SEST) and the Nordic optical

Telescope(NOT).Ouractiveparticipationinsev-

eralinternationalprojectssecuresthecontinuityof

highqualityastronomicalresearch.

Increasingthevolumeofresearchwithexternalfund-

ing: Modern astronomicalresearch is team work,

whereoneoftenencounterstheterm\criticalmass"

usedin dening afunctional researchgroup. The

Observatory encourages all eorts by the perma-

nentstato acquireexternalfunding fortheirre-

searchgroups. Themostimportantfundingsources

are the Academy of Finland, the National Tech-

nology Agency of Finland, European Union and

privatefoundations.

Spaceresearch: Our increasingspace research ac-

tivityisaninvestmenttothefutureofAstronomy.

Ourspace researchinstrumentdevelopmentguar-

anteesusfutureobservingtimewithseveralsatel-

lites. Furthermore, we get positive publicity, as

wellasnewstudentstothisexpandingeldofAs-

tronomy. Thefractionofspaceresearchfundingin

theObservatorybudgethasbeensteadily increas-

ing. The fact that Astronomy is oneof the most

popularnaturalsciences,hasallowedusto utilize

theopportunitiesinspaceresearch,andourcontri-

butionindeningthegoalsofthiseldofresearch

inFinlandhasbeensignicant.

EÆcientPh.D. teaching: ThePh.D. degreeisthe

\basicdegree"foraresearcherinAstronomy. The

timetoreachthisdegreewillbeshortened,which

willalsoincreaseourresearchvolume. Weaimfor

a moreeÆcient Ph.D. student supervision inside

the research groups, and we continue to partici-

pateactivelyinthenational\GraduateSchoolfor

Astronomy and Space Physics". In spring 2001,

weinitiatedaprogram,whereapersonal\teacher

tutor"isselectedevenforeveryundergraduatestu-

dentstudyingAstronomyashis/hermainsubject.

In short, we do our best to encourage close con-

nections between the students and the research

groups.

PublicOutreach: Astronomyenjoystheinterestof

the general public, and it is also a highly pop-

ular minor subject in the University of Helsinki.

We aim at increasing our eectiveness in report-

ingaboutastronomicalresearch,e.g. in thepress,

televisionandwww. Wehavecloseconnectionsto

theAlmanacOÆce attheObservatory, aswellas

to the Finnish Amateur Astronomer Association

URSA.

ThepopularityofthebasiccoursesinAstronomyhas

been constantly growing. Continuous development of

these basic courses also strengthens the motivation of

students majoring in Astronomy. Another major goal

forthesebasiccoursesistoteachthemodernworldpic-

tureofnaturalsciencetothestudentsfrom allfaculties

oftheUniversityofHelsinki. Thedirectconnectionbe-

tweenAstronomycoursesandtheresearchperformedat

the Observatory will be strengthened. As an example

oftheeectivenessofthisstrategy,wementionthat the

research project performed by thestudents during one

undergraduate level course has already been published

inaninternationalrefereedjournal.

Thefundingandthevolumeofourresearchbetween

1995and2000isillustratedbelow. Thechosenstrategy

seemstopredictasuccessfulfuture fortheObservatory

oftheUniversityofHelsinki.

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and star formation

Projectnumber 81525002

Researchagreements AcademyofFinland

Typeofresearch Basicresearch

Directorofresearch Prof.Mattila,Kalevi

Telephone 09-19122947

Fax 09-19122952

E-mail Kalevi.Mattila@Helsinki.Fi

ResearchstawithaPh.D. KaleviMattila,Prof

JormaHarju,Docent

MikaJuvela,Docent

KimmoLehtinen,Ph.D.

MarkRawlings,Ph.D.

DelphineRusseil,Ph.D.

Viktor,Toth,Ph.D.

Ph.D.student(s) PaiviHarjunpaa,Phil.Lic.

JereKahanpaa,M.Sc.

SamuKontinen,M.Sc.

AskoPalviainen,M.Sc.

PetriVaisanen,M.Sc.

M.Sc.student(s) PeterJohansson

CajusPomren

Associatedresearchsta LauriHaikala,Docent

Technicalsta MikkoToriseva,Lic.Tech.

2.1 Research activities

Theactivitiesof theInterstellarMedium and StarFor-

mationresearchgrouparedirectedtothefollowingelds:

1)theevolutionofdustandmoleculargasininterstellar

clouds;2)theformationofprotostarsindensemolecular

cloudcores; 3) radiativetransferand magnetohydrody-

namic(MHD)modelingofinterstellarclouds;and4)star

formationhistoryanddustemissionathigh redshifts.

Thersttopicinvolvesthestudyofgrainpopulations

andtheirphysicalpropertiesanddistributionsinmolec-

ularclouds,whicharecorrelatedwiththepropertiesand

chemical composition of the gas component. The aim

is to understand the interrelation between interstellar

gasanddustanditsdependenceonphysicalconditions,

suchasthekinetictemperature,density,star-formation

activityand external radiation eld. These studies are

conductedviaobservingfar-infraredand(sub)millimetre

continuumemission fromdust and molecularline emis-

sionfromgas.

Thesecondtopiccontainsprotostellaraccretiondisks

and the violent ejection of `surplus' material through

jets, which drive shocks and outows in the surround-

ing gas. The parameters of shocks associated with ac-

cretion/outowarestudied withtheaidofthermaland

maserline emission. The nature and theoriginof pro-

tostellar jetsarestudied with theaidofinterferometric

continuumimaging.

The study of the star formation in the early Uni-

verseconcentratesonthefar-infraredandoptical/near-

infraredbackgroundradiation,andinfrared-brightgalax-

ies. Both topics are related to the dust content of the

forming and very young galaxies, and depend on the

physical processes taking place in them. The group is

developingmethods of component separation to disen-

andotherforegroundcomponents.

TheMonte Carloradiativetransfercodesdeveloped

inthegroupareessentialtoolsofresearchforthisgroup.

Thecodesare used formodelingof radio spectrallines

and infrared emission from galactic and extragalactic

molecularclouds. Thecombinationwith realisticcloud

modelsfrom MHDcalculationsmakesitpossibletode-

rivethephysicalcharacteristicsofasourcefromitsemis-

sionproperties.

Theresultsemergingfromtheresearchofthisgroup

will allow detailed testing of the current theories con-

cerninginterstellarcloud evolution,chemistry, andstar

formationin theMilkyWayandothergalaxies attheir

earlieststages.

2.2 Progress

Thegroupisfollowingamulti-wavelengthobservational

approach wheretop-classspaceborneand ground-based

infrared,(sub)millimetre,andradiotelescopesarebeing

utilized. Sofarthetwoobservationalfacilitiesmostim-

portant for the group have been ESA's Infrared Space

Observatory(ISO)andtheSwedish-ESOSubmillimetre

Telescope(SEST) at ESO/La Silla. The launch of the

OdinsatelliteinFebruary2001hasopenedupanimpor-

tantnewanduniqueresearchopportunityforthegroup.

Based on its ISO experience, the group is participat-

ing since 2000 in the relevant Planck Surveyorscience

projects.

2.2.1 Recent workand achievements

The group has discovered for the rst time the

so-called Unidentied Infrared Features between

6.2 and 11.3 m in the diuse disk emission of

anexternal galaxy(NGC891)with ISO.Thecar-

riers of these features which are suspected to be

some form of the PolycyclicAromatic Hydrocar-

bons(PAH's)areamajor,stillunidentiedcompo-

nentoftheinterstellarmediuminourGalaxyand

in other galaxies (Mattila, Lehtinen & Lemke

1999). Earlierwehavediscovered,alsofortherst

time, the "PAH" bands in alocal interstellar cir-

ruscloud(Lemke,Mattila,Lehtinenetal. 1997)

andin thedisk emissionofourGalaxy(Mattila,

Lehtinenet al. 1996).

Based on extensive ISO far-IR mapping we have

analysed the dust properties and detected proto-

starsandnewlyformedstarsinseveralnearbymo-

lecularclouds,starformationregions,andglobules

(Lehtinenetal. 1998,1999,2000)

Using SEST we havecarried out several research

projectswhich, in addition to theirown scientic

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theOdin satellite or ascomplimentary/follow up

studiesforour ISO projects: Extensivemappings

ofnearbymolecularcloudshavebeenusedtostudy

thedynamicalandchemicalevolutionofpre-stellar

andprotostellarcoresandtheirrelationtonewly-

born stars (e.g. Anderson et al. 1999, Konti-

nen et al. 2000). Interaction between protostel-

larsystemsandtheirimmediatesurroundingshave

beenstudied withtheaid ofhigh-resolutionspec-

tralline(SEST)andradiocontinuum(ATCA)ob-

servations(Anderson etal. 1997a,b; Harjuet al.

1998,2000).

UsingISOPHOTfar-IR mapsofseveralverydark

patchesintheskywehavebeenabletodetectnew

extragalacticsourcesandperformgalaxycountsat

90, 150, and 180 m (Juvela, Mattila & Lemke

2000). The sources already detected form asub-

stantialpartofthecosmicinfraredbackgroundra-

diation. Extensive galaxy counts at the near-IR

Jand Kbands havebeen performed in twolarge

elds which were included in the joint European

LargeAreaISOSurvey(ELAIS).Thesecountsare

the most extensive ones so far performed at the

intermediateJmagnituderange. Theresultsindi-

catea high normalization for the NIR galaxylu-

minosity function withoutstrong evolutionin the

giantgalaxypopulation(Vaisanen etal. 2000).

AneÆcientMonte Carlocodehasbeendeveloped

forthe treatment of radiation transfer in clumpy

molecularclouds(Juvela 1997). It hasbeensuc-

cessfullyappliedto theinterpretationofanexten-

siveSESTmultitransitionCSsurveyofhigh-mass

starformationregions(Juvela1998),tomodelling

ofCOemissionfromlocal clouds(Padoan,Juve-

laet al. 1998, 1999a,1999b), and to modeling of

COemissionfromprotogalaxies(Jimenez, ...,Ju-

vela,et al. 2000).

Thegrouphasasubstantialpublicationrecordfor

the past 5 years: 50/55 papers have been pub-

lished/acceptedin refereed journals during 1996-

2000.

2.3 Money and resources

2000: Man-monthsofwork: 129

Externalnancing:

AcademyofFinland: 1900000FIM

GraduateSchoolforAstronomyandSpace

Physics: 190000FIM

tal: 22000FIM

2.4 Tests of learning

Kontinen, Samu

Tahtienvalisten molekyylienpylvastiheyksien

johtaminenradiospektriviivahavainnoista;M.Sc.

thesis;2000;DepartmentofPhysics,Universityof

Helsinki

2.5 Visits abroad

Mattila,Kalevi

MPIfurAstronomie,Germany,23.-24.10.2000,

2days

EuropeanSouthernObservatory,Garching,Ger-

many,6.-7.6. 2000,2days

EuropeanSouthernObservatory,Garching,Ger-

many,28.-29.11.2000, 2days

UniversityofLeiden,Netherlands,20.6. 2000,

1day

Svenskarymdbolaget,Solna,Sweden,8.9. 2000,

1day

CopenhagenUniversityObservatory,15.11.2000,

1day

Harju, Jorma

Australian Telescope National Facility, Par-

kes,Australia,8.-23.4. 2000,16days

Australian Telescope National Facility, Nar-

rabri,ATCA,Australia,21.-31.5. 2000,11days

ObservatoiredeParis,France,13.-15.9. 2000,

3days

Toth,Viktor

University of Manchester (IAU General As-

sembly),GreatBritain,9.-16.8. 2000,8days

KonkolyObservatory,Budapest,Hungary,De-

cember2000, 7days

Rawlings,Mark G.

RoyalAstronomicalSociety,AstrophysicalChem-

istryGroup,United Kingdom,3-7.3. 2000,5days

NATOAdvancedStudyInstituteSummerSchool,

Italy, 4.-17.6.2000, 14days

U.K.InfraredTelescope(U.K.I.R.T.),Hawaii,

UnitedStates,10.-22.8. 2000,13days

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ImperialCollege,GreatBritain,15.-16.6.2000,

2days

EuropeanSouthernObservatory,Germany,7.-

8.12. 2000,1day

UniversityofManchester, GreatBritain,14.-

19.8. 20006days

2.6 Visiting academics

StephenHotzel, Dipl.Phys., doktorand, Germany,

45days

JanWouterloot, Ph.D.,Netherlands,60days

GianfrancoDeZotti,Italy,3days

ViktorToth,Ph.D., Hungary,20days

2.7 Papers read at scientic confer-

ences, symposia, meetings etc.

Mattila,Kalevi

"ResultsfromtheInfraredSpaceObservatory",

XXXIVAnnualConferenceoftheFinnishPhysical

Society,9.-11.3.2000,Espoo,Finland

"UIR band emission from NGC 891", Work-

shop, Lorentz Center, University of Leiden, 20.6.

2000,Leiden,Netherlands

"Extragalacticbackgroundradiationinthein-

frared",24.10. 2000,Heidelberg,Germany

Harju, Jorma

"Odininlaukaisumarraskuussa2000-Linnun-

radan tason ja pimeiden sumujen tutkimusohjel-

mat", VIII Cospar-Meeting of the Finnish Space

Researchers, 25.-27.9. 2000, Helsinki-Tukholma-

Helsinki,Finland

"Radio imaging of protostars and prospects

forstudieswithALMA", XXXIVAnnualConfer-

enceoftheFinnish PhysicalSociety,9.-11.3.2000,

Espoo,Finland

Juvela, Mika

"Cosmicinfraredbackground: ISOPHOTsource

counts",XXXIVAnnualConferenceoftheFinnish

PhysicalSociety,9.-11.3.2000,Espoo,Finland

"FarInfraredExtragalacticBackgroundRadi-

ation: Source countswithISOPHOT",IAUGen-

eral Assembly, Symposium 204, 15.-18.8. 2000,

Manchester,GreatBritain

diation: Source Counts with ISOPHOT ", IAU

GeneralAssembly,Symposium204,15.-18.8. 2000,

Manchester,GreatBritain

"Linnunradancirruspilvetjaekstragalaktinen

taustavalo", VIII Cospar-Meeting of the Finnish

Space Researchers, 25.-27.9. 2000, Helsinki-Tuk-

holma-Helsinki,Finland

Lehtinen, KimmoK.

"ISOPHOTFIR surveysof nearbymolecular

clouds", Planck LFI Consortium Meeting, Plan-

ning the Planck-satelliteresearch, 24.-26.2. 2000,

Saariselka,Finland

"ISOPHOTfar-infraredsurveyofnearbymolec-

ular clouds", XXXIV Annual Conference of the

FinnishPhysicalSociety,9.-11.3.2000,Espoo,Fin-

land

"ISO-satelliitinhavaintojatahtiensyntyalueis-

ta",VIIICospar-MeetingoftheFinnishSpaceRe-

searchers, 25.-27.9. 2000, Helsinki-Tukholma-Hel-

sinki,Finland

"SuomenTahtitieteilijaseuraesittaytyy",VIII

Cospar-MeetingoftheFinnishSpace Researchers,

25.-27.9. 2000, Helsinki-Tukholma-Helsinki, Fin-

land

"Compactmolecularclouds,cloudcores,glob-

ules", Planck LFI Consortium Meeting, Planning

the Planck-satellite research, , 19.-21.10. 2000,

JodrellBank Observatory,Maccleseld, Cheshire,

GreatBritain,

Vaisanen, Petri

"Newwideeldnear-infraredgalaxycounts",

XXXIVAnnualConferenceoftheFinnishPhysical

Society,9.-11.3.2000,Espoo,Finland

"NewwideeldJ-andK-bandgalaxycounts

andtheextragalacticbackgroundradiation",IAU

24th General Assembly, 16.8. 2000, Manchester,

UnitedKingdom

"GalaksitutkimusavaruusteleskoopeillaISOja

SIRTF",VIII Cospar-MeetingoftheFinnishSpa-

ce Researchers, 25.-27.9. 2000, Helsinki-Tukhol-

ma-Helsinki,Finland

"Newnear-infraredgalaxycountsandthecos-

mic NIRbackgroundradiation",7.12. 2000,ESO

SouthernObservatory,Garching,Germany

"NewwideeldJ-andK-bandgalaxycounts

andtheextragalacticbackgroundradiation",IAU

24th General Assembly, 15.-18.8. 2000, Manch-

ester,UnitedKingdom

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"Pre-stellar cores", Seminary of the Astron-

omy Section of the Hungarian Physical Society,

13.12.2000,Budapest,Hungary,invitedspeaker

Rawlings, MarkG.

"Heavily-reddenedlinesofsightin thegalaxy

(Rawlings,MarkG.&Adamson,A.J. &Whit-

tet, D. C. B.)", NATOAdvanced Study Institute

"SolidStateAstrochemistry",5.-16.6. 2000,Erice,

Italy,poster

"ISOPHOTStudiesoftheinterstellarmedium

&reectionnebulae(Rawlings,MarkG.&Leh-

tinen, Kimmo K. & Mattila, Kalevi)", VIII

Cospar-MeetingoftheFinnishSpaceResearchers,

land,poster

Kontinen,Samu

"Molecular line study of evolution in proto-

stellar cloud cores", YERAC 2000 (nuorten eu-

rooppalaisten tahtitieteilijoiden vuosittainen kon-

ferenssi),17.-20.9. 2000,Granada,Spain

Kahanpaa, Jere

"Galaksin NGC 253kaukoinfrapunaemissio -

matkaISO-havainnoistafysikaaliseenmalliin",VIII

land,poster

2.8 Membershipinscienticandschol-

arly societies

Harju, Jorma

Finnish National Committee of URSI, 2000-

2002,Finland,boardmember

Lehtinen,KimmoK.

Suomentahtitieteilijaseurary,1.1.-31.12.2000,

Finland,chairman

Toth, Viktor

AstronomySectionoftheHungarianPhysical

Society,1999-2001,Hungary,chairman

inations of doctoral dissertations

Mattila,Kalevi

AlanNielsen: "AnObservationalStudyofPhoto-

Evaporating,Bright-RimmedInterstellarStarForm-

ingCloudsinthemm-andOpticalRegime.",Uni-

versityofCopenhagen,15.11. 2000,Denmark,act-

ingasOpponent

2.10 Additional information

Mattila,Kalevi

EuropeanSouthernObservatory,expertadvi-

sorin ESOObservingProgrammesCommittee

Member, Scientic Organizing Committee of

theODINSatellite

Co-InvestigatoroftheISOPHOTExperiment

(ESA/ISO)

AssociateScientist,PlanckSurveyor(ESA)

Rawlings,Mark G.

Actedasscienticrefereeforproposalsto the

U.K.panelfortheallocationoftelescopetime(P.-

A.T.T.). Granted observing time for 3 proposals

for telescope time (principal investigator on two,

co-investigatoronone).

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NationalTechnologyAgency(appl.

(tech.research,endedinApril1999)

NationalTechnologyAgency

(Pigmentproject,1999-2001)

Typeofresearch Basicresearch,share:70%

Appliedresearch,share:20%

Developmentwork,share:10%

Directorofresearch Prof.Lumme,Kari

Telephone 19122910

Fax 19122952

E-mail Kari.Lumme@Helsinki.Fi

ResearchstawithaPh.D. KariLumme,Prof

LarsLamberg,Ph.D.

Ph.D.student(s) KimGreen,M.Sc.

M.Sc.student(s) RiikkaKangaslampi

AnttiPenttila

SeppoPietarinen

JaniTyynela

ThePlanetaryResearch Group(PRG) doesresearchin

lightscattering and radiativetransfer and applies itto

variousplanetarysystemobjectsandtovarioustechno-

logicalapplications,specicallyto pigmentsandpaper.

3.2 Progress

ThePRGattheUniversityofHelsinkiObservatoryhas

concentratedonsomekeytheoreticalproblemsrelevant

tomodernsolarsystemstudies. Theseactivitiesinclude

the analysis and modelling of dust and aerosol parti-

clesbothonthesurfaces ofatmospherelesssolarsystem

bodies,inMartianatmosphereandintheinterplanetary

space and cometary comae. Interestingly enough light

scattering studies haverecentlyfound applications also

in thepigment,paperandpaintindustries. Thereason

forthis isthat in these areasscatteringplaysanessen-

tialrole. This researchhasbeensupported bothbythe

NationalTechnologyAgency ofFinlandand variousin-

dustrialcompanies.

Lummeisparticipating at aCo.Ilevelbothin the

MarsExpress/HRSC-experimentandin theMicrograv-

ity project (ICAPS) on board the International Space

Station (ISS).The PRG is taking the responsibility to

analyzeandmodelthepropertiesofthesmalldustpar-

ticlesintheMartianatmosphere. IntheICAPS-project,

thegroupisresponsiblefordevelopingandtestingvari-

ouslightscatteringandradiativetransfercodes.

ThePRGhassystematicallystudiedandfurtherde-

veloped demanding codes to compute light scattering

bynonsphericalparticles. Developed byourowngroup

wehaveformulatedaso-calledIntEq(integralequation)

code which is capable of computing light scattering by

anyirregular solidor aggregatedparticle. The particle

canalso beopticallyanisotropicorinhomogeneous.

lightscatteringbyarotationallysymmetricsolidparticle

oranaggregatecomposedofspheres. Thesecodeshave

been improvedand somefundamental errorshavebeen

corrected.

The PRGhas also activelybeenstudying how par-

ticlesize and shapestatisticcanbededuced fromtheir

projections,mainlyobtainedfromtheTEM-images. We

havealsobeenabletodevelopquitenewalgorithmshow

irregularsolid canbe closely-packed without any over-

lapping. Theseareimportantbothintheeldofcosmic

duststudiesandseveralindustrialapplications.

Wearecurrentlytryingtounderstandthelargedata

set of cometary polarization by applying our extensive

pooloflightscatteringcodes. Itseemsquitereasonable

that in near future we will knowmuch moreabout the

cometarydust.

ThePRGconsistsof sevenresearchersand students

partlypaid bythe funds from theAcademy of Finland

andtheNational TechnologyAgency. Thegroupleader

Kari Lumme has in the last few years given several

invited talks in international meetings. Eight refereed

papershavebeenpublished inthelastthreeyears.

Basicresources: 500000FIM.

3.4 Visits abroad

Lumme,Kari

ObservatoiredeParis,France,4.-8.3. 2000, 5

days

Hadamcik Edith, Dr., France, August 2000, 20

days,researchguest

Lumme,Kari

"Lightscattering bycosmic dust",Asteroids,

comets...,9.-14.4.2000,Canterbury,GreatBritain

"Komeettapolyn polarisaatio ja tulkinta val-

onsirontamenetelmilla",VIIICospar-Meetingofthe

FinnishSpaceResearchers,25.-27.9. 2000,Helsin-

ki-Tukholma-Helsinki,Finland

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NationalTechnologyAgency

Typeofresearch Basicresearch,share:50%

Developmentwork,share:50%

Directorofresearch DocentVilhu,Osmi

Telephone 19122801

Fax 19122952

E-mail Osmi.Vilhu@Helsinki.Fi

ResearchstawithaPh.D. OsmiVilhu,Docent

JuhaniHuovelin,Docent

DianaHannikainen,Ph.D.

JarkkoLaukkanen,Ph.D.

JukkaNevalainen,Ph.D.

Ph.D.student(s) LauriAlha,M.Sc.

SamiMaisala,M.Sc.

PanuMuhli,M.Sc.

JuhoSchultz,M.Sc.

M.Sc.student(s) EeroEsko

PetterNikula

IirisSoranta

Associatedresearchsta PasiHakala,Docent

JuriPoutanen,Docent

Theresearchprogrammeisdividedinto twoparts:

I.Fundamentalscience

II.Developmentofnewinstruments.

I. The rst part consists of scientic return (guar-

anteed time) from the instrument projects the group

is involved in (INTEGRAL, SMART-1,SRG), comple-

mentedbydatafromsatellitesalreadyexisting(e.g. X-

MM-Newton,Chandra,HST).Thesecondpartisacon-

tinuationtotheongoinghardwareprojectsincludingre-

searchalsoindetectorandmaterialphysics,withactive

collaboration between several institutes inside and ex-

ternalto theUniversityofHelsinki.

Thesciencetopicsaddressedbyourresearchinclude

hard tailsand superorbital periods of Low Mass X-ray

Binaries,broadbandspectralmodellingofmicroquasars

andAGNs,spectralevolutionandafterglowsofGamma-

ray bursts, coronae and aring in active stars and the

Sun, and X-ray scattering from the lunar surface. In

particular,theverybroadspectralcoverage(e.g. INTE-

GRAL ,SRG)and thepossibilityforaverylongmoni-

toring(SMART-1cruisephase),coupledtosophisticated

theoreticalmodelling, arethekeyincredientsofoursci-

enceprogramme.

II. Development of future instruments is a natural

continuation to the ongoing projects, where the group

hasgained experience, providing valuableaccess to the

guaranteedtimealsoin thefuture. Theaimistoutilise

advancesin instrumentperformance carriedalong with

biggertelescopes,largereld-of-viewanddecreasednoise

ofnewsystemsinthefutureplansofESA(XEUS),indi-

vidualcountries(ROEMER/Denmark,Submillimetron/

Russia)andMIT/NASA(AXM/GEM).Thespecicim-

provementswhicharemeaningfulare:

olutionwithXEUS,whichenablesstudiesofX-rayspec-

traof Galacticsources withthe samequalitywenowa-

dayscaninvestigatethesolarcorona,

2) almost full sky eld-of-view in X-rays with moder-

atespectralresolution(AXM)givingafreedomtoselect

targetsofinterestandstudytheirtemporalandspectral

behaviourinalltimescalesfromsecondsto months,

3)fastresponseto Gamma-raybursts(ROEMER/Bal-

lerina)enablingstudiesofearlyphasesoftheX-rayand

opticalafterglows.

4.2 Progress

Thegrouphasreceivedobservationtimefromastronomi-

calsatellites(ASTRO-E,XMM-Newton,Rossi-XTE,Ch-

andra). The Nordic Optical Telescope (NOT) in La

Palma,and MOST inAustralia havealsobeenusedby

thegroup. Thegrouphasstudied accretiondisksof bi-

narystars,microquasars,hotplasma ofgalaxyclusters

and X-ray activity of Sun-like stars. On the theoreti-

cal side, geneticalgorithms and mechanismsproducing

optical and X-ray polarisation have been studied. An

importantpartofthegroup'swork consistsofscientic

instrumentprojectsforsatellites. These include theX-

ray spectrometer SIXA (SRG satellite, launch in 2004,

PI and 2 Co-I's in the group), X-ray monitor JEM-X

(INTEGRAL satellite, launch in 2002, 4 Co-I's in the

group), and solar X-ray monitor XSM and lunar uo-

rescence analyzer D-CIXS (SMART-1 satellite, launch

in 2003,Co-PIand 2Co-I'sin thegroup). Majormile-

stonesininstrumentdevelopmentduring2000were,

1)SIXApassedsatellitelevelacceptancetests,

2)theQualicationModelofJEM-Xwascompleted,and

3)mechanicalmodeloftheXSMwascompletedandde-

livered.

Theeducationalactivitiesofthegroupincludeduni-

versity courses and supervising of doctoral and under-

graduatestudents, resultingto 2 doctoral, and 1mas-

ter's degreein our groupduring 2000. Also, 2persons

with recent doctoral degrees obtained an international

levelpost-docpositionabroad(UniversityofSouthamp-

ton;ESA/ESTEC).

Externalnancing:

AcademyofFinland: 1200000FIM

NationalTechnologyAgency: 5964000FIM

(10)

Nevalainen, Jukka

DeterminingcosmologicalparametersusingX-

rayanalysesofclustersofgalaxiesandtheCepheid-

luminosityrelation;dissertation;2000;Department

ofAstronomy,UniversityofHelsinki

Laukkanen, Jarkko

Advanced experimental methodsin Compton

scatteringspectroscopy;dissertation;2000;Depart-

mentofPhysics,UniversityofHelsinki

ViliLamsa

AsoftX-raySolarMonitorforSMART-Isatel-

lite; M.Sc. thesis; 2000; Department of Physics,

UniversityofHelsinki

4.5 Visits abroad

Vilhu, Osmi

Danish Space Research Institute, Denmark,

6.-8.12.2000,3days

Universityof Granada, Spain, 3.-14.9. 2000,

12days

Huovelin,Juhani

EuropeanGeophysicalSociety,France,27.-29.4.

2000,3days

SMART-1D-CIXS/XSMTeamMeeting,United

Kingdom,16.-18.10. 2000,3days

NordicOpticalTelescope,Spain,5days

Hannikainen, Diana

Department of Physics and Astronomy, Uni-

versityofSouthampton,GreatBritain,7-11.2.2000,

5days

Department of Astrophysics, School of Phy-

sics,UniversityofSydney,Australia,9.3-3.4. 2000,

26days

AAO/ANTF,Australia,16-17.3. 2000,2days

UniversityofAlicante,4thINTEGRALWork-

shop,Spain,4.-8.9. 2000,5days

Department of Physics and Astronomy, Uni-

versity of Southampton United Kingdom, 10.5.-

2000,235days

Laukkanen, Jarkko

EuropeanSynchrotronRadiationFacility,ESRF,

Grenoble,France,19.-29.4. 2000,11days

Britain,16.-18.10. 2000,3days

ESRF, Grenoble, France, 25.10.-4.11. 2000,

11days

Muhli,Panu

UniversityofSouthampton,GreatBritain,19.-

20.10. 2000,2days

EuropeanGeophysicalSociety,France,27.-29.4.

2000,3days

Osservatorio Astronomico di Palermo, Italy,

3.-10.9. 2000,8days

SMART-1D-CIXS/XSMTeamMeeting,United

Kingdom,16.-18.10. 2000,3days

Schultz, Juho

NordicOptical Telescope,Spain,5days

NordicOptical Telescope,Spain,4days

ASA/ESASummerSchool"EctragalacticAs-

tronomyandcosmologyfromspace",Austria,18.-

27.7. 2000,10days

EneErgma,Dr.Sc.,professor,UniversityofTartu,

Estonia,120days

Mait Muntel, University of Tartu, Estonia, 120

days

Vilhu, Osmi

"DeepIntegralPrintingtowardsLargeMagel-

lanicClouds", 4thIntegralWorkshop,September

2000,Alicante,Spain

"ThermalComptonizationinGRS1915-105",

3rdMicroquasarWorkshop,September2000,Gra-

nada,Spain

"Jem-X: X-ray monitor on board Integral",

ObservingwithINTEGRALWorkshop,April2000,

LesDiableters,Switzerland

"AXMjamikrokvasaarit",VIIICospar-Meet-

ingoftheFinnishSpaceResearchers,25.-27.9. 2000,

Helsinki-Tukholma-Helsinki,Finland

"Integral-satelliitin havainto-ohjelma 1: Suu-

ri Magellanin Pilvi", VIII Cospar-Meeting of the

ki-Tukholma-Helsinki,Finland

(11)

"TheXrayspectrometer(XSM)forSMART-

1",ConferenceoftheEuropeanGeophysicalSoci-

ety,26.-30.4. 2000,Nice,France,poster

"BeppoSAX-havaintoja Linnunradan keskus-

alueestakohteenEXS1737.9-2952suunnassa",VIII

land

"TheX-raysolarmonitor(XSM)forSMART-

1spaceprobe",ProceedingsoftheXXXIVAnnual

ConferenceoftheFinnishPhysicalSociety,9.-11.3.

2000,Espoo,Finland,poster

Hannikainen, Diana

"TheradioemissionfromGROJ1655-40dur-

ingthe1994ejectionepisodes",AAO/ATNFWork-

shop,16-17.3. 2000,HunterValley,Australia

"The radioemissionfromtheX-raytransient

XTE J1550-564", 4th INTEGRAL Workshop, 4-

8.9. 2000,Alicante,Spain

"XTEJ1550-564:Asuperluminalejectionevent

duringthe September1998 outburst",3rdMicro-

quasarWorkshop,11-13.9. 2000,Granada,Spain

Laukkanen, Jarkko

"Electronic momentum anisotropy in quasi-

crystals-InelasticX-rayscatteringstudyonAl

0:71 -

Co

0:17 Ni

0:11

", XXXIV Annual Conference of the

Finnish Physical Society, 9.-11.3. 2000, Espoo,

Finland,poster

"Inelasticscatteringstudyonthehigh-T

c su-

perconductor La

1:85 Sr

0:15 CuO

4

- Anisotropy and

electronicproperties",SagamoreXIII-Conference

onCharge,SpinandMomentum Densities,3.-9.9.

2000,StareJablonki,Poland,poster

"Compton-sirontakvasikiteista",X-rayphysics

laboratoryNobel-seminar2000,8.12. 2000,Baltic

Sea

"D-CIXS/XSM update", X-rayphysics labo-

ratoryNobel-seminar2000,2000,8.12. 2000,Baltic

Sea

Muhli,Panu

"MonitoringX-raybinarieswithlong-termvari-

ability",XXV GeneralAssemblyof theEuropean

Geophysical Society (SMART-1 D-CIXS Splinter

Meeting),27.-29.4. 2000,Nizza,France

"Monitoringthelong-termvariabilityofX-ray

binarieswithSMART-1",X-RayAstronomy2000,

3.-10.9.2000,Mondello (Palermo),Italy

binarieswithSMART-1",SMART-1D-CIXS/XSM

TeamMeeting, 16.-18.10. 2000, Abingdon, Great

Britain

Schultz, Juho

"Kertymakiekkojenpolarisaatio",VIIICospar-

MeetingoftheFinnishSpaceResearchers,25.-27.9.

2000,Helsinki-Tukholma-Helsinki,Finland

"Simulationsofpolarizationfromaccretiondisks",

34. XXXIVAnnualConferenceoftheFinnishPhys-

icalSociety,9.-11.3.2000,Espoo,Finland

4.8 Membershipinscienticandschol-

arly societies

Vilhu, Osmi

International Astronomical Union. Commis-

sion42"CloseBinaryStars",boardmember

International Astronomical Union, Commis-

sion 44 "Space Astronomy and High Energy As-

trophysics",boardmember

Vilhu, Osmi

PrincipalInvestigatorofSIXA(onboardSRG

launch2003).

Co-Investigator of Jem-X (on board Integral

launch2002).

Co-InvestigatorofXSM(onboardSMART-1

launch2002).

Huovelin, Juhani

PrincipalInvestigatorofESA'sSMART-IXSM

experiment

Co-InvestigatorofINTEGRAL/JEM-X

Co-investigatorofSIXA(onboardSRG)

(12)

Typeofresearch Basicresearch

Directorofresearch DocentMuinonen,Karri

Telephone 19122941

Fax 19122952

E-mail Karri.Muinonen@Helsinki.Fi

ResearchstawithaPh.D. KarriMuinonen,Docent

LauriJetsu,Docent

MikkoKaasalainen,Ph.D.

JukkaPiironen,Ph.D.

Phdstudent(s) ThomasHackman,M.Sc.

MikaKokko,M.Sc.

JenniVirtanen,M.Sc.

JohannaTorppa,M.Sc.

TeemuLaakso,DI

SannaKaasalainen,M.Sc.

M.Sc.student(s) JoonasLyytinen

JyriNaranen

OlaviLindroos

Associatedresearchsta TimoNousiainen,Ph.Lic.

ThescienticinterestsofSPAcan bedividedintothree

main overlappingcategories:

(i)astronomicalobservations

(ii)fundamental physics

(iii)inverseproblems

Astronomicalobservationsarecarriedoutusingmod-

erntelescopes(e.g., NordicOptical Telescope) in aster-

oid photometry, polarimetry, and astrometry, and the

photometry and spectroscopy of late-type stars. SPA

playsacrucial rolein the calibrationofthe forecoming

multi-wavelength SMART-1/AMIE and D-CIXS obser-

vations of the Moon in the visual and X-rays. Infun-

damentalphysics,boththeoreticalandexperimentalad-

vancesare beingmade. As to theory, theSPA research

isfocussedonscatteringandabsorptionof lightbysin-

gle small particles and by particulate media, and the

celestial mechanics of the few-body problem, whereas

experiments are being carried out to measure albedos

of singlesmall particlesand backscatteringcharacteris-

tics of particulate media (scattering laboratory at the

Observatory).SPAisparticipatingintheICAPSexper-

iment(InteractionsinCosmicandAtmosphericParticle

Systems)aboard theInternationalSpace Station (ISS).

The SPA inverse problems can be divided into mathe-

matical methods and astronomical applications. As to

the former,SPA isdevelopingtechniquesforstatistical

determinationofasteroidorbits,forthecomputation of

collisionprobabilityofnear-Earthobjects,forlightcurve

inversionof physical properties of asteroids(e.g., rota-

tionandshape,microscopicsurfaceproperties),andfor

time-series analyses. As to the latter, theapplications

include,e.g.,theimpacthazardfromnear-Earthobjects,

interpretationoflunarvisualandX-Rayimagingduring

stellarmagneticactivity,andindustrialapplications.

5.2 Progress

Inwhat follows,SPA publicationsin theyear 2000are

briey reviewed. Erikson et al. (2000)published their

thirdcompilationpaperonnear-Earthasteroidobserva-

tions,includinglightcurvesof12asteroids. Thisworkis

organizedbyDLR(Berlin)andPiironencontributedby

observingasteroid(1917)Cuyoin1995. Piironenetal.

(2000) compiled all outdoor data of small-phase-angle

measurements from the years 1979-81, 1985, 1987 and

1999. Theirresultsindicatedthat snowshowscoherent-

backscattering-typeenhancement of intensity near zero

phaseangle. Piironenparticipatedintwoobservational

campaignsofanactivestarEVUMaandaquasar(Kata-

jainen et al. 2000, Villata et al. 2000). Both of these

objectsexhibitoccasionalandnon-periodicoutbursts.

Tedescoetal.(2000)examinedapromisingnewtech-

nique for detecting near-Earth asteroids: space-based

infrared observations. Computer simulations indicated

that such a space-based survey would be signicantly

moreeÆcientthanagroundbasedvisualsurvey.

Muinonen(2000a)reviewedlightscatteringbysto-

chasticallyshapedparticles(inparticular,Gaussianran-

domparticles)foracornerstonebook onLightScatter-

ingby NonsphericalParticles(Academic Press). Mui-

nonen (2000b) further introduced a so-called axisym-

metricGaussianrandomparticle,whichiscomputation-

allyattractive(cf.,T-matrixmethod)andhasintriguing

futureapplications. Muinonen&Saarinen(2000)pub-

lishedapioneeringstudyoflightscatteringbyGaussian

randomcylinders, withforeseeableapplications in pulp

andpaperindustry,andMuinonen(2000c)studiedthe

eect of clustering on the scattering characteristics of

Gaussianrandomparticles.

S.Kaasalainenetal. (2000)carriedoutacompara-

tive,partlysemiempiricalstudyoftheoppositioneects

foratmospherelesssolar systembodies. Using astatis-

tical, inversion-theoreticaltechnique,they were able to

estimatetheamountandcharacterofphotometricdata

necessaryforwell-denedoppositioneects. Stankevych

etal. (2000)continuedtheirthoroughstudyoftheshad-

owingmechanismin particulatemediaofopaquespher-

icalparticles. M. Kaasalainen&Torppa (2000)pre-

sented new, robust methods for deducing the shapes,

rotational states, and scattering properties of large ir-

regularbodiesfromtheirlightcurves.

Nousiainenet al. (2000)applied the second-order

perturbationtheorytoradarbackscatteringbynonspher-

ical ice particles (with emphasis on the University of

Helsinkiradar). Miloslavskayaetal. (2000)studied the

wavelengthandpolarizationdependenceoftransmission

(13)

marizingsomechallengingopentransmissionproblems.

Jetsu& Pelt (2000) demonstrated how the round-

ing of terrestrial impact crater ages introduces spuri-

ous(i.e., unreal)periodicitiesinto such aseries of time

points. Hackman in collaborationwith theOulu Uni-

versityAstrophysicsgroup,continuedto investigatethe

evolution ofmagnetic regions of FK Comaetype stars.

The two stars, HD199178and FK Comae, included in

theobservation programme(NordicOpticalTelescope),

both show long-lived large high latitude spots (Korho-

nen et al. 2000, Hackman et al. 2000). Jetsu et al.

(2000)analyzed a timeseries ofBV-photometry of the

chromosphericallyactivebinaryV815Her. Spotsonthe

surface of the star caused an amplitude of 0.05-0.2 in

theV-lightcurve. Variationsinthephotometricrotation

period indicatesurfacedierentialrotation.

Sincethebeginningofitsactivitiesin1998,SPAhas

published altogether (7+1)+(10+6)+(9+8) = (26+15)

=41articlesineitherrefereedscienticjournalsorrefer-

eedscienticproceedings(inaddition,asofMarch2001,

with2+0published,10+0inpressand6+0submitted).

Along with its steeply growing publication rate, SPA

is becoming anevermoresuccessfulscienticcoalition,

withgreatprospectsforitsfuture.

Keywords: absorption,scattering,multiplescatter-

ing, coherentbackscattering, small particles, reection,

regolith, asteroids, comets, planetary satellites, plane-

tary rings, interplanetary dust, atmospheric particles,

celestial mechanics, statistical orbitdetermination, im-

pacthazard,collisionprobability,numericalintegrators,

Hamiltonian dynamics, time series analysis, solar-type

stars, cool stars, variable stars, stellar activity, stellar

magnetism,stellarspots,stellardierentialrotation,stel-

larDopplerimaging

Specialresources: 130000FIM.

Externalnancing:

Academy of Finland, 'Light Scattering by

GaussianRandomMedia': 450000FIM

AcademyofFinland,'Coherentmultipleback-

scatteringbyinhomogeneousmedia': 42300FIM

AcademyofFinland,AcademyResearchFel-

lowpost: 280000FIM

MinistryofEducation,'GraduateSchoolfor

AstronomyandSpace Physics': 190000FIM

Muinonen,Karri

Lowell Observatory, Arizona, United States,

27.10.-3.11.2000,3days

SAGEMS.A.,France,12.-13.1. 2000, 2days

Piironen,Jukka

Uppsala University, Astronomiskaobservato-

riet,Sweden,14.-25.2. 2000,12days

Hackman, Thomas

UppsalaUniversity,AstronomiskaObservato-

riet,Sweden,5.-9.4. 2000,4days

NordicOpticalTelescope,Spain,7.-19.8.2000,

13days

Virtanen,Jenni

LowellObservatory,UnitedStates,29.9.-22.11.

2000,55days

YurijShkuratov,FT,visitingscientist,Astronom-

ical Observatory, Kharkov State University, Uk-

raine,8.-19.5. 2000,12days

YurijShkuratov,FT,visitingscientist,Astronom-

ical Observatory, Kharkov State University, Uk-

raine,6.-17.11. 2000,12days

Dmytro Stankevich, FT, visitingscientist, Astro-

nomicalObservatory,KharkovStateUniversity,Uk-

raine,8.-19.5. 2000,12days

Dmytro Stankevich, FT, visitingscientist, Astro-

raine,6.-17.11. 2000,12days

Olga Myloslavskaya, FT, visiting scientist, Insti-

tute for Low Temperature Physicsand Engineer-

ing,Ukraine,9.-19.5. 2000,12days

Olga Myloslavskaya, FT, visiting scientist, Insti-

tute for Low Temperature Physicsand Engineer-

ing,Ukraine,6.-17.11. 2000,12days

VadimKaydash,FT,visitingscientist,Astronomi-

calObservatory,KharkovStateUniversity,United

ArabEmirates,6.-17.11. 2000,12days

Andriy Ovcharenko, FT,visiting scientist, Astro-

raine,8.-19.5. 2000,12days

AstaPellinen-Wannberg,FT,dosentti,SwedishIn-

stitute ofSpace Research,Kiruna, Sweden,12.12.

2000,1dayofdepartment

(14)

Muinonen,Karri

"Collision probability for Earth-crossing as-

teroids.",US-EuropeanCelestialMechanicsWork-

shop,3.-7.7. 2000,Poznan,AdamMickiewiczUni-

versity,Poland,invitedspeaker

"LightscatteringbyaxiallysymmetricGaus-

sianrandom particles", Light Scatteringby Non-

sphericalParticles,28.8.-1.9. 2000,Halifax,Canada

"Initial statisticalranging oforbitsfortrans-

Neptunianobjects",InternationalAstronomical

Union,TheXXIVthGeneralAssembly,JointDis-

cussion4,TheTransneptunianPopulation,7.-18.8.

2000,Manchester,United Kingdom

"Coherent Backscattering of Light by Solar

SystemBodies: EÆcientVectorComputation",32nd

AnnualMeetingoftheDivision forPlanetarySci-

ences, Americal Astronomical Society, 23.-27.10.

2000,Pasadena,CA,UnitedStates

"SMART-1AMIEja D-CIXS/XSMkokeiden

teoreettisetvalonsirontamenetelmat",VIIICospar-

2000,Helsinki-Tukholma-Helsinki,Finland

"Computationsofcoherentbackscatteringand

shadowingeects foratmosphereless solarsystem

objects", Light Scatteringby Nonspherical Parti-

cles,28.8.-1.9. 2000, Halifax,Canada,poster

"Wavelengthdependentdepolarizationoflight

transmittedthroughslabsofAl

2 O

3

powder",Light

ScatteringbyNonsphericalParticles,28.8.-1.9. 2000,

Halifax,Canada,poster"Coherentbackscattering

byinterplanetarydustparticles",IAUColloquium

181, Dust in the Solar System and Other Plane-

tary Systems, 10-14.4. 2000, Canterbury, United

Kingdom,poster

"Circular polarimetric observations of aster-

oids", 32nd Annual Meeting of the Division for

Planetary Sciences, Americal Astronomical Soci-

ety,23.-27.10.2000,Pasadena,CA,UnitedStates,

poster

Piironen,Jukka

"Lightcurveinversionofasteroid6489Golevka",

EuropeanGeophysical Society, XXV General As-

sembly,24.-29.4. 2000,Nice,France

"SMART-1AMIE:kokeellisetmenetelmat",

VIIICospar-MeetingoftheFinnishSpaceResearch-

ers, 25.-27.9. 2000, Helsinki-Tukholma-Helsinki,

Finland

periments: implicationstothelunaroppositionef-

fect", European Geophysical Society, XXV Gen-

eralAssembly,24.-29.4. 2000,Nice,France,poster

Kaasalainen, Mikko

"Asteroid shapes, periods, poles and photo-

metric properties from lightcurves ", Division of

planetary Sciences, 2000, AmericanAstronomical

Society,October,Pasadena,CA,United States

"Valokayrainversioasteroiditutkimuksessa",

Finland

"Deductingtheshapesandscatteringproper-

ties of asteroids and other irregular bodies from

their lightcurves", Light Scatteringby Nonspher-

ical Particles, 28.8.-1.9. 2000, Halifax, Canada,

poster

Hackman, Thomas

"Surfaceimagingofstarspots",VIIICospar-

2000,Helsinki-Tukholma-Helsinki,Finland,poster

"Surface imagingof late typestars",Finnish

AstronomicalSocietyMeeting,26.5. 2000,Helsinki,

Finland

Kaasalainen, Sanna

"Modelling of shadowingand coherentback-

scattering: comparisontoplanetaryphasecurves",

International Astronomical Union, The XXIVth

GeneralAssembly,JointDiscussion12,Highlights

ofPlanetaryExplorationfromSpaceandfromEarth,

7.-18.8.2000,Manchester,UnitedKingdom,poster

"Comparativestudiesontheoppositioneect

in thesolarsystem", 32ndAnnualMeetingof the

Division for Planetary Sciences, Americal Astro-

nomical Society, 23.-27.10. 2000, Pasadena, CA,

UnitedStates,poster

"Jaisten aurinkokunnan kappaleiden opposi-

tioefektin vertailua", VIII Cospar-Meeting of the

ki-Tukholma-Helsinki,Finland,poster

Virtanen,Jenni

"CollisionprobabilitiesforEarth-approaching

asteroids", 32nd Annual Meeting of the Division

forPlanetarySciences,AmericalAstronomicalSo-

ciety,23.-27.10. 2000,Pasadena,CA,UnitedStates

"Initial-orbital-rangingforEKOsandNEOs",

Finland

(15)

arly societies

Muinonen,Karri

sion15,1997-2000,secretary

sion15,OrganizingCommittee,2000-,boardmem-

ber

InternationalAstronomicalUnion,Working

Group for Near-Earth Objects, Organizing Com-

mittee,2000-,boardmember

Groupfor Near-Earth Objects, Technical Review

Committee,2000-,expertmember

TheSpaceguardFoundation,1996-,boardmem-

ber

FinnishNationalCommitteeofAstronomy,1998,-

Finland,secretary

Piironen,Jukka

TelescopioNazionaleGalilei,TimeAllocation

Committee,Italy,expertmember

Hackman, Thomas

Ursa,14.11. 2000-,Finland,boardmember

Muinonen,Karri

GroupforDistantObjects,member2000-.

InternationalSpaceStation,ESATopicalTeam

onCosmicDust,member1997-.

5thConferenceonElectromagneticandLight

ScatteringbyNonsphericalParticles:Theory,Mea-

surements,andApplications,Halifax,Canada,2000

28.8.-1.9. 2000, Member of Scientic Organizing

Committee.

VIIICospar-MeetingoftheFinnishSpaceRe-

searchers,25.-27.9. 2000, Helsinki-Tukholma-Hel-

sinki,Finland,MemberofOrganizingCommittee.

(16)

6.1 Scientic monographies

Nevalainen, Jukka: Determining cosmological

parametersusingX-rayanalysesofclustersofgalax-

iesandthecepheidperiod-luminosityrelation. Ph.D.

Dissertation. Universityof Helsinki 2000, 43,[49]

p.

ers: Program and abstracts, Helsinki-Tukholma-

Helsinki 25.-27.9. 2000. University of Helsinki

2000,38s.

6.2 Articles in refereed journals

1. Durouchoux, Ph., Sood, R., Oka, T., Seers, M.,

Sa-Harb,S.,Vilhu, Osmi, Huovelin, Juhani,

Thresher,D.,Corbel, S., O'Neill, P.: Jet interac-

tionofSS433withtheambientmedium. Advances

inspaceresearch25(2000): p. 703-708

2. Durouchoux, Ph.,Sood, R.,Smith, I., Corbel, S.,

Hannikainen, Diana, Lover,R.: Millimeterob-

servationsofthecandidatesoftgamma-rayrepeater

SGR1814-13.Advancesinspaceresearch25(2000):

p. 765-768

3. Erikson,A.,Mottola, S.,Lagerros,J.S. V., Lind-

gren, M., Piironen, Jukka, Oja, T., Hahn, G.,

Lagerkvist,C.-I.,Harris,A.W.,Nathues,A.,Neu-

kum,G.: TheNear-EarthObjectsFollow-UpPro-

gram:III:Lightcurvesof12objectsfrom1992and

1995. Icarus147(2000): p. 487-497

4. Green, Kim, Lamberg, Lars, Lumme, Ka-

ri: Stochastic modelling of paper structure and

Monte-Carlo simulation of light scattering. Ap-

pliedoptics29(2000): p. 4669-4683

5. Hannikainen,Diana,Hunstead,R.W.,Campbell-

Wilson,D., Wu, K., McKay, D. J., Smits, D. P.:

RadioemissionfromGROJ1655-40duringthe1994

jet ejection episodes. Astrophysical journal 540

(2000): p. 521-534

6. Harju, Jorma, Winnberg, A., Wouterloot,J. G.

A.: The distribution of OH in Taurus Molecular

Cloud-1. Astron. Astrophys.353 (2000): 1065-

1073

7. Henning, Th., Lapinov, A., Schreyer, K., Steck-

lum,B.,Zinchenko,Igor: IRAS12326-6245:Lu-

minousvery young stellarobjectswith a massive

molecularoutow. Astron. Astrophys. 364(2000):

613-624

Henry, G. W., Kokko, Mika, You, J.: Time se-

riesanalysisofV815Herculisphotometrybetween

1984 and 1998. Astron. Astrophys. 362(2000):

223-235

9. Jetsu,Lauri,Pelt,J.: Spuriousperiodsintheter-

restrialimpact craterrecord. Astron. Astrophys.

353(2000): 409-418

10. Jimenez, R., Padoan, P., Dunlop, J., Bowen, D.,

Juvela,Mika,Matteucci,F.: Proto-galacticstar-

burstsathigh redshift. Astrophysical Journal532

(2000): p. 152-169

11. Juvela,Mika, Mattila,Kalevi,Lemke,D.: Far

infraredextragalacticbackgroundradiation: I.Sour-

cecountswithISOPHOT.Astron. Astrophys. 360

(2000): 813-832

12. Jaaskelainen,A.J.,Peiponen,K.E.,Raty,J.,Tap-

per,U., Richard, O., Kauppinen,E. I., Lumme,

Kari: Estimationofrefractiveindexofplasticpig-

mentsby Wiener bounds. Optical engineering39

(2000): p. 2959-2963

13. Katajainen, S., Lehto, H. J., Piirola, V., Kart-

tunen, H., Piironen, Jukka: AM Herculis star

EVUMa(RE1307+535)inahighaccretionstate.

Astron. Astrophys. 357(2000): 677-680

14. Kiss,Cs., Toth, Viktor, Moor,A., Sato, F., Ni-

colic, S., Wouterloot, J. G. A.: Low massclouds

in the Cepheus-Cassiopeia void: I.Khavtassi 15.

Astron. Astrophys. 363(2000): 755-766

15. Kontinen,Samu,Harju,Jorma,Heikkila,Arto,

Haikala,L.K.: Molecularlinestudyofevolutionin

protostellar cloudcores. Astron. Astrophys. 361

(2000): 704-718

16. Korhonen,H.,Berdyugina,S.V.,Hackman,Tho-

mas, Strassmeier, K. G., Tuominen, I.: Studyof

FKComaeBerenices: II.Spotevolutionfrom1994

to 1997. Astron. Astrophys. 360 (2000): 1067-

1076

17. Muinonen, Karri,Saarinen, K.: Ray optics ap-

proximationforGaussianrandomcylinders. Jour-

nalofquantitativespectroscopyandradiativetrans-

fer64(2000): p. 201-218

18. Nevalainen,Jukka,Markevitch,M.,Forman,W.:

TheclusterM-Trelationfromtemperatureproles

observed with ASCA and ROSAT. Astrophysical

Journal532(2000): p. 694-699

(17)

X-ray totalmass estimate for the nearby relaxed

cluster A3571. Astrophysical Journal536(2000):

p. 73-78

20. Oliver,S., Rowan-Robinson,M., Mattila, Kale-

vi,Vaisanen, Petri: TheEuropeanLargeArea

ISOSurvey: I.Goals,denitionsandobservations.

Monthly Notices of the R. Astronomical Society

316(2000): p. 749-767

21. Padoan, P., Juvela, Mika, Bally, J., Nordlund,

A.: Acomparisonofsup[13]COLTEandtruecol-

umn densities in molecular cloud models. Astro-

physicalJournal529(2000): p. 259-267

22. Peiponen,K.E.,Jaaskelainen,A.,Raty,J.,Richard,

O., Tapper, U., Kauppinen, E. I., Lumme, Ka-

ri: Reectance studyofpigmentslurries. Applied

spectroscopy54(2000): p. 878-884

23. Potter,S.B.,Cropper,M.,Hakala, Pasi: Stokes

imagingofthe accretion regionin magneticcata-

clysmicvariables: II.V347 Pav. Monthly Notices

oftheR.AstronomicalSociety315(2000): p. 423-

431

24. Ramsay,G.,Cropper,M.,Wu,Kinwah,Mason,K.

O.,Hakala, Pasi: Detectionof theopticalcoun-

terpart of the proposed double degenerate polar

RX J1914+24. Monthly Notices of theR. Astro-

nomicalSociety311(2000): p. 75-84

25. Rawlings, Mark G., Adamson, A. J., Whittet,

D.C.B.: A searchforhighly reddenedearly-type

stars:opticalphotometryandspectroscopyofstars

in theStephenson objective prismsurvey. Astro-

physicalJournal. Suppl.ser131(2000): p. 531-559

26. Stankevych, D., Shkuratov, Yu. G., Muinonen,

Karri, Miloslavskaya, O.: Simulation of shading

systemsofopaqueparticles. Optikaispektroskopija

88(2000): p. 619-622

27. Tedesco, E. F., Muinonen, Karri, Price,S. D.:

Space-basedinfrarednear-Earthasteroidsurveysi-

mulation. Planetaryand space science48 (2000):

p. 801-816

28. Toth,Viktor,Hotzel,S.,Krause,O.,Lehtinen,

KimmoK.,Lemke,D.,Mattila,Kalevi,Stickel,

M.,Laureijs,R.J.: ISOPHOTSerendipitySurvey

observationsof interstellarclouds: I.Detection of

theColdestCoresin Chamaeleon. Astron. Astro-

phys. 364(2000): 769-779

29. Villata,M.,Piironen,Jukka: The0716+714WE-

BT campaign of February 1999. Astron. Astro-

phys. 363(2000): 108-116

P., Cohen, M.: Wide-eld J- and K-band galaxy

counts in the Europeanlarge-areaInfraredSpace

Observatorysurvey elds. Astrophysical Journal

540(2000): p. 593-604

31. Zinchenko,Igor,Henkel,C.,Mao,R.Q.: HNCO

in massive galactic dense cores. Astron. Astro-

phys. 361 (2000): 1079-1094; Erratum.,Astron.

Astrophys. 363(2000): 1195

6.3 Other refereed articles

1. Juvela,Mika,Mattila,Kalevi,Lemke,D.:Cir-

russpectraoflowsurfacebrightnessregions. ISO

beyondpointsources: studiesofextendedinfrared

emission workshop, ISO Data Centre, Villafranca

delCastillo,Madrid,Spain,14-17September1999

p. 99-

2. Juvela,Mika,Mattila,Kalevi,Lemke,D.:Cos-

mic Inrared Background; ISOPHOT FIR source

counts at 90, 150 and 180m. ISO surveysof a

dustyuniverse: workshopatRingbergCastle,Ger-

many,November8-12,1999p. 88-95

3. Kaasalainen, Mikko, Torppa, Johanna: De-

ducingtheshapesandscatteringproperties ofas-

teroidsandotherirregularbodiesfromtheirlight-

curves. Lightscattering bynonsphericalparticles

: Halifaxcontributions, August28-September1,

2000,Halifax,Canadap. 275-278

4. Keranen,Sanna,Muinonen,Karri,Piironen,

Jukka: Computations of coherentbackscattering

andshadowingeectsforatmospherelesssolarsys-

temobjects. Lightscatteringbynonsphericalpar-

ticles: Halifaxcontributions,August28-Septem-

ber1,2000,Halifax,Canadap. 279-282

5. Lehtinen,KimmoK.,Mattila,Kalevi,Lemke,

D.: Far-infrared ISOPHOT observations of glob-

ules. ISO beyond point sources: studies of ex-

tendedinfraredemissionworkshop,ISODataCen-

tre,VillafrancadelCastillo, Madrid,Spain,14-17

September1999p. 137-

6. Lehtinen,KimmoK.,Mattila,Kalevi,Lemke,

D.,Heikkila, Arto: ISOPHOT far-infraredsurvey

onnearbymolecularclouds. ISOsurveysofadusty

universe: workshopat RingbergCastle,Germany,

November8-12,1999p. 317-324

7. Lumme, Kari: Scattering propertities of inter-

planetarydust particles. Lightscatteringbynon-

sphericalparticles: theory,measurements,andap-

plicationsp. 555-582

(18)

Karri,Stankevich, D., Piironen, Jukka: Wave-

lengthdependentdepolarizationoflighttransmit-

ted through slabs of Al

2 O

3

powder. Light scat-

tering by nonspherical particles: Halifax contri-

butions, August 28 - September 1,2000, Halifax,

Canadap. 325-327

9. Muinonen,Karri: Lightscatteringbystochasti-

callyshapedparticles. inLightscatteringbynon-

sphericalparticles: theory,measurements,andap-

plications,AcademicPress,NewYork,p. 323-352

10. Muinonen, Karri: Light scattering by axially

symmetricGaussianrandomparticles. Lightscat-

tering by nonspherical particles: Halifax contri-

butions, August 28 - September 1,2000, Halifax,

Canadap. 91-94

11. Muinonen,Karri: Rayopticsapproximationfor

random clusters of Gaussian spheres. Observing

landfrom space: science, customersand technol-

ogyp. 209-217

12. Nousiainen, Timo,Muinonen, Karri, Avelin,

Juha, Sihvola, Ari: Microwavebackscattering by

nonsphericalice particles using second-orderper-

turbation series. Light scattering by nonspheri-

cal particles: Halifax contributions, August 28 -

September1,2000,Halifax,Canada143-146

13. Piironen,Jukka,Muinonen,Karri,Keranen,

Sanna,Karttunen,H.,Peltoniemi,J.I.: Backscat-

tering oflight by snow: eld measurements. Ob-

serving land from space : science, customers and

technologyp. 219-228

and 2000

1995 M.Sc. DianaHannikainen

1996 Ph.Lic. PaiviHarjunpaa

1997 M.Sc. AskoPalviainen

1997 Ph.D. MikaJuvela

1998 M.Sc. SannaKeranen

1998 Pd.D. KimmoLehtinen

1998 Ph.D. JukkaPiironen

1999 M.Sc. JereKahanpaa

1999 M.Sc. JuhoSchultz

1999 M.Sc. JohannaTorppa

1999 M.Sc. JenniVirtanen

1999 Ph.D. DianaHannikainen

2000 Ph.D. JukkaNevalainen

M.Sc. Ph.Lic. Ph.D.

1995 1 - -

1996 - 1 -

1997 1 - 1

1998 1 - 2

1999 4 - 1

2000 - - 1