Astrotomography

TheideaforthisbookoriginatedintheLaSillaobservatorywheretwoofthe editorsweredoingphase-resolvedspectroscopyofsomecataclysmicvariable starsusingtheNTT. Werealizedthatalthoughindirectimagingtechniques suchaseclipsemappingandDopplertomographyhadbeenaroundformore thanadecadeandhadprovidedsomeofthemostinterestingdiscoveries,no bookexistedwhichcoveredthesetechniques. Moreover,nocolloquiumhadever beenorganizedspeci?callyonthesetopics. Theimplementationoftomographic methodsinastrophysics,inordertoprobestructuresonangularscalesofmic- arcseconds,startedabout15yearsagowiththedevelopmentoftheeclipsem- pingmethod. Thismethodisabletoreconstructlightdistributionsineclipsing binariesbyexploitingtheregularobscurationofthelightsourcebyoneofthe binarycomponents. Asimilarapproachtoregulariseddata?ttingleadtoa- rietyofrelatedmethodsinordertoresolvelightdistributionsoftheaccretion ?owsinbinaries,thesurfacestructuresofstarsandtheinnerregionsofactive galaxies. Thescienti?coutputofthesemethodsisconsiderableandtheyare increasinglybecomingversatiletoolsforawidecommunityofresearchers. Aspecialisedworkshopseemedhighlydesirable,sowedecidedtoorganise the?rstinternationalworkshoponastrotomography. Theideaofthemeeting, whichtookplaceinBrusselsinearlyJuly2000,wastobringtogetherresearchers sharinganinterestinapplyingindirectimagingmethodsinastronomy,andto comparethemethodsusedindi?erent?elds. Duringthemeeting,alargeamount oftimewasdevotedtoextensivereviewsofthevariousreconstructiontechniques. Inconjunctionwiththereviews,shortcontributedtalkshighlightedrecent- sultsanddevelopments. Duetothesmallnumberofparticipants,60,therewas plentyofopportunityfordiscussionandinteraction. Moreover,wewantedthat theproceedingsofthismeetingcouldbeusedasahandbookonthesemethods. Thereviewerswerethereforeaskedtoprovideextensiveaccountsoftheir?eld. Theproceedingsthusconsistof13reviewsofabout25pageseachaswellas 15contributedtalksof6?8pages. Awiderangeoftopicsarediscussed,mostly onthepropertiesofaccretion?owsinsemi-detachedbinarysystemsconta- ingacompactstellarremnant. Othertopicsincludethesurfaceandmagnetic ?eldstructureofsinglestars,theshockwavesofMirastars,theaccretion?ows aroundblackholesinbinariesandactivegalacticnucleiandthestructureof Algolsystems. Thelargevarietyofsubjectscoveredisaclearillustrationofthe importancethatindirectimagingtechniqueshavegainedinastrophysics. Anew VI generationofopticaltelescopesandspectrographsiscomingon-linewhichwill pushthepossibilitiesofindirectimagingevenfurther. Inconjunctionwiththat, specialisedinstrumentsandprojectsonexistingtelescopeswilldeliverdatasets withhightimeandwavelengthresolutionstailoredforaccuratemapping- periments. Wehopethattheseproceedingswillprovideahelpfuloverviewfor anyresearcherinterestedinsuchtechniques. Withthesamespiritofproducing morethanjustproceedings,wealsoincludealistofsomeusefulresourceson theInternet. Wealsohopethatthewebpageoftheworkshopwillbekeptalive andbecomeausefulreferenceonastrotomography. Wewouldliketothankalltheparticipantsformakingthisworkshopas- cess,andinparticularallthecontributingreviewauthorsforhavinggenerously agreedtocometothemeetingattheirownexpense,andfortheire?ortsin providingabalancedsetofreviewpapers. Manythankstoallthemembersof thelocalorganisingcommitteeforthehardworkbefore,duringandafterthe workshop. TheBrusselsPlanetariumisthankedforprovidinguswithameeting venueandexcellentsupport. WealsowishtothanktheDirectoroftheRoyal ObservatoryofBelgium,Prof. PaulPaquet,forhise?orts. RobHynesprovided uswithasuperb'scienti?cimpression'ofaninteractingbinarythatfeaturedon theworkshopposterandvariousotherlocations. Finally,wearegratefulfo- nancialsupportfromprojectG. 0265. 97oftheResearchProgrammeoftheFund forScienti?cResearch-Flanders(F. W. O. -Vlaanderen). Brussels,Southampton, HenriBo?n, November2000 DannySteeghs, JanCuypers Workshopwebpage:http://www. astro. oma. be/DopplerWorkshop/ Contents DopplerTomography T. R. Marsh...1 MappingthePeculiarBinaryGPCom L. Morales-Rueda,T. R. Marsh,R. C. North...27 ...