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Symbiotic Stars with Similar Line Profiles during Activity1 N. A. Tomov∗, M. T. Tomova∗ and D. V. Bisikalo† ∗InstituteofAstronomyandNationalAstronomicalObservatory,BulgarianAcademyofScience, 3 POBox136,BG-4700Smolyan,Bulgaria 1 †InstituteofAstronomy,RussianAcademyofScience,48PyatnitskayaStreet,RU-119017Moscow,Russia 0 2 Abstract. Line profiles containing indication of bipolar collimated outflow along with P Cyg absorption during phase of n activity of several symbiotic systems are considered. The Hg profile of Z And during its 2006 outburst consisted of four a groups of components. The profile of the HeI l 5876 line of the Hen 3-1341 system during its 1998–2004 outburst had J high-velocity satellitecomponents on one hand and abroad P Cyg absorption on other hand. The Ha and Hb profiles of 3 theBF Cygsystem during its2006–2012 outburst had satellitecomponents, observed forthe firsttime,along withPCyg 1 absorptions. These profiles are interpreted in the light of a model related to the strong recurrent outbursts of Z And. The AGDrasystemduringits2006 outburstdidnot containindicationof collimatedoutflow. Itsprofilesareinterpretedinthe ] lightofthemodelrelatedtothefirstoutburstof2000–2012activephaseofZAnd. R Keywords: stellar activity, symbiotic binaries, line profiles, individual stars (Z Andromedae, Hen 3-1341, BF Cygni, AG Draconis), S accretion,massloss,stellarwindsandoutflows . PACS: 97.10.Gz,97.10.Jb,97.10.Me,97.80.Gm h p - o 1. INTRODUCTION r t s Symbioticstarsarelong-periodinteractingbinariesconsistingofacoolvisualprimaryandahotcompactsecondary a [ componentaccretingmatterfromtheatmosphereofitscompanion.Theirspectralvariabilityisdeterminedfromboth theorbitalmotionandtheoutbursteventsofthehotcomponentwhichareoftenaccompaniedbyintensivelossofmass 1 intheformofopticallythickshells,stellarwindoutflowandbipolarcollimatedjets.Thenatureofthecollimatedjets v issubjectofintensivetheoreticalinvestigationandtheviewtheyrepresentoutflowfromanaccretingcompactobject 2 6 is widely accepted [1]. The collimated bipolaroutflow, however,could arise due to a stellar wind, if mechanism of 7 collimationisavailableinthesystem.Suchamechanismcanberelatedtodisc-likeformationsurroundingthewhite 2 dwarfwhichprovidesasmallopeningangleoftheoutflowingjets. 1. TheZAndsystemisconsideredasaprototypeoftheclassicalsymbioticstars.Itconsistsofanormalcoolgiantof 0 spectraltypeM4.5[2],ahotcompactobjectwithtemperaturehigherthan105 K [3,4]andanextendedsurrounding 3 nebulapartlyphotoionizedbythehotcomponent.Itsorbitalperiodis758.d8,whichisbasedonbothphotometric[5] 1 and radial velocity [6] data. The last active phase of Z And began at the end of 2000 August [7] and continues up : v to now includingseven optical eruptions.The maxima of the light duringthis phase were in 2000 December,2002 i November,2004September,2006July,2008January,2010Januaryand2012January[8,AAVSOdata].Ascenario X forinterpretationofthelinespectrumofZAndduringthisactivephasecontainingtwostagesoftheevolutionofthe r accretingcompactobjectwassuggestedintheworksofTomovetal.[9,10].Itissupposedthatathinaccretiondisc a fromaccretionofastellarwindexistsinthesystemandtheobservedtwovelocityregimeofmassoutflowfromthe compactobjectduringthefirstoutburstoftheactivephaseisexplainedwithacollisionofonepartoftheoutflowing materialwiththediscanddecreaseofitsvelocity.Thefirstoutburst(andeveryfollowingone)givesbirthtoconditions adisc-likeenvelopesurroundingtheaccretiondisctoforminthesystem,whichcancollimatetheoutflowingmaterial duringthefollowingoutburstsandthegrowthofthecollimatedoutflowinparallelwiththedevelopmentofthewindis thusexplained.DuringthefirstoutburstofZAndin2000–2002twovelocityregimeofthemassoutflowwasobserved. Duringits2006–2007outburstdevelopmentofastellarwindtogetherwithabipolarcollimatedoutflowwasobserved on the otherhand. Some otherclassical symbiotic stars have similar behaviorduringtheir active phases. The mean aimofthisworkisselectedlinesofsomeothersymbioticbinariesduringtheiractivephasestobeconsideredandto showthattheirprofilescanbeinterpretedintheframeworkofthescenarioproposedforZAnd. 1 BasedonobservationscollectedattheRozhenNationalAstronomicalObservatory,Bulgaria Fast wind (HI (B), HeII (B)) Slow wind (P Cyg lines) Accretion disc (HI (N)) Shock ioization (HeII (N)) FIGURE1. Leftpanel:Schematicmodeloftheregionaroundthehotcomponentduringthefirstoutburst.Rightpanel:Thesame, butintheplaneperpendiculartotheorbitalplanewheretheemissionregionsareshown.(FromspectroscopypresentedinTomov etal.[12].) 2. OBSERVATIONSANDREDUCTION ThespectroscopicobservationswereobtainedwiththePhotometricsCCDcameramountedontheCoudéspectrograph ofthe2mRitchey–Chrétien-Coudé(RCC)telescopeoftheRozhenNationalAstronomicalObservatory.Thespectral resolutionwas0.2Åpx−1onalloccasions.Whenmorethanoneexposurewastakenpernight,thespectrawereadded withtheaimofimprovingthesignal-to-noiseratio.TheIRAFpackage2wasusedforthedatareductionaswellasfor obtainingthedispersioncurve,calculatingtheradialvelocitiesandequivalentwidths. ThelinefluxesweredereddenedonusingtheextinctionlawinthepaperbyCardellietal.[11]. 3. THESPECTRAL VARIABILITYOF ZAND 3.1. The model WeproposedamodelforinterpretationofthelinespectrumofZAndduringits2000–2012activephase[9,10].It wasconcludedthatasaresultofaccretionofthestellarwindfromthegiantstarathinaccretiondisk,locatedinthe orbitalplane,formsaroundthecompactobjectinthequiescentstateofthesystem.Theestimatesofthesizeandmass ofthediscshowitsinnermostpartcanbeopticallythickinthequiescentstate.Duringtheactivephaseanaccretion discwithamassof50–80percentofitsinitialmassexists,too(see[9]andreferencestherein). Duringthefirstoutbursttheoutflowingmaterialwithahighvelocitycollideswiththeaccretiondisc.Asaresult,the ejectavelocitydecreasesintheregionoftheorbitalplaneanddoesnotchangeathigherstellarlatitudes(Fig.1,left panel).Thedecreaseofthevelocityleadstoanincreaseofthedensityandtheleveloftheobservedphotosphereresides furtherawayfromthestar.Athigherstellarlatitudesthelevelofthephotosphereresidesclosertothestar.Inthisway an optically thick disc-like shell forms in the orbital plane, which plays the role of the observed photosphere.This shelloccultsthehotcompactobjectandsincetheshellhasalowereffectivetemperature[8,13,14]itisresponsible forredistributionofthecontinuumenergyandagrowthoftheopticalfluxofthestar.TheobservedPCygabsorption isrelatedtothisshell(seeFig.1,rightpanel). Duringtheactivephasethewindofthecompactobject“strips”theaccretiondiscandejectssomepartofitsmass. Attheendofeachoutburstsomepartoftheejectedmasslocatesinthepotentialwellofthecompactobject.Afterthe cessationofthewinditbeginstoaccreteagain.Becauseofconservationoftheinitialangularmomentumadisc-like envelopeformssurroundingthe disc which envelopeis located at a greaterdistance from the orbital plane than the accretion disc itself. The existence of centrifugalbarrier leads to the appearance of two hollow cones with a small 2 TheIRAFpackage isdistributed bytheNational Optical AstronomyObservatories, whichisoperated bytheAssociation ofUniversities for ResearchinAstronomy,Inc.,undercontractwiththeNationalScienceFoundation. Satellite components > P Cyg region Accretion disc Fast wind Shock ionization Disc-like envelope FIGURE2. ThesamelikeinFig.1butduringrecurrentstrongoutburst. openingangle(15◦–30◦)aroundtheaxisofrotation(seeFig.2,leftpanel)[15,16]. During the first outburst, disc-like envelope does not exist. The following outbursts during the active phase, the extendeddisc-likeenvelopecancollimatethewind,whichinthiscaseoccupiesonlythetwohollowconesandbipolar outflow forms(Fig. 2, left panel). This outflow is observedas highvelocity satellite components,situated on either sideofthemainpeakoftheemissionline.Theirpresenceinthespectrumdependsonthedensityofboththedisc-like envelopeandthe outflowingmaterial. These componentswill appearonly if the density of the disc-like envelopeis high enough to providecollimation and the mass-loss rate of the outbursting componentis also high. Accordingto ourmodeltheyareexpectedtobeobservedduringoutburstsaccompaniedbymass-lossathighratesandprecededby similarstrongoutburst. Theobservedbroademissioncomponentsindicatinganopticallythinstellarwindwithahighvelocityappearclose tothecompactobjectwheretheoutflowingmaterialmovesinalldirections(Fig.2,rightpanel).Thegasoutflowing close to the surface of the cone, whose velocity is lower than that along to the cone axis, can contribute to these emission components too. Depending on the inclination angle of the orbit and the opening angle of the cone the outflowclosetotheconesurfacecanhavearadialvelocity,whichmakesitabletoemitatwavelengthsfarawayfrom thecenterofthesatelliteemission. 3.2. The 2000–2002outburst We will consider only the Hg and HeI profiles of Z And during its 2000–2002 brightening to illustrate the interpretationof its line spectrum. All of the lines observedby us are considered in the work of Tomov et al. [12]. Duringthisoutburstanadditionallow-intensityemissioncomponentoftheHg linewithaheightof∼0.5ofthelocal continuumandFWZIof∼1000kms−1wasseentogetherwithitsnarrowcomponent(Fig.3,rightpanel).Theintensity ofthebroademissionreacheditsmaximalvalueatthetimeofthemaximallightwhereasthebehaviorofthenarrow 15 y 4 it s n e nt10 i e v ti la 5 2 e R 0 -500 0 500 -500 0 500 Heliocentric RV (km/s) FIGURE3. TheprofileoftheHg line.ThespectrumofJanuary7,1999takeninthequiescentstateofthesystemisshownin theleftpanel.ThespectraofNovember17(dot-dashline)andDecember5(solidline),2000takenduringtheoutburstphaseare shownintherightpanel.TheGaussianfitofthebroadcomponentisshowntoo.Thelevelofthelocalcontinuumismarkedwitha dashedline. componentwas different.Thatis whywe considerthatthe Hg line consistedin this way ofa narrowcomponentof nebulartypeandabroadcomponent.ThebroademissioncomponentwasanalyzedbyfittingwithGaussianfunction. ThebluewingofthebroadcomponentwasnotseeninNovember2000(Fig.3)whichprobablyresultedfromthe absorptionbythestellarwindformingthePCyglines(seebelow).We considerthatthebroademissioncomponent oftheHg lineindicatesanopticallythinstellarwindwithahighvelocityof∼500kms−1 fromthecompactobjectin thesystem,whichwindwasalsoobservedintheHeIIl 4686line. 3.5 HeI 4471 HeI 4713 3.0 1999 Jan. 7 nsity2.5 2000 Nov. 17 e nt e i2.0 v ati Rel1.5 1.0 0.5 -500 0 500 -500 0 500 Heliocentric RV (km/s) FIGURE4. TheprofilesoftheHeItripletlinesinquiescence(January1999;dot-dashedline)andnearthemaximumofthefirst outburst(November2000;solidline).(FromspectroscopypresentedinTomovetal.[12].) ThetripletlinesofheliumHeIl 4471andHeIl 4713hadpurelyemissionprofileandFWHM=45–50kms−1in thequiescentstateofthesystem.Ablue-shiftedPCygabsorptionwithavelocityof∼60kms−1appearedinNovember andDecember2000duringthetimeofthemaximallight.InNovemberthisabsorptionhadtwocomponentstructure (Fig.4).TheHeI l 4471line reachedaresidualintensityof0.46in Novemberand0.60inDecember,respectively. Since the coolgiant’scontinuumatthe same time amountedto ∼0.07–0.08of the totalcontinuumof the system at thewavelengthsoftheselines[17],theirappearancecanbe relatedtoopticallythickoutflow(stellarwind)fromthe outburstingcompactobject.MoreoversomepartoftheHg lineonNovember17,2000wasprobablyalsoabsorbedby thiswindasfarasitsabsorptiondiphasthesamewavelengthposition(Fig.5). IntheframeworkofourmodeltheHg andHeI profilesofZ Andcanbeinterpretedinthenextway.We suppose thata geometricallythin accretiondisc existsin the system in the beginningof the firstoutburstof the activephase andtheinnerregionofthisdisc canbe opticallythick.Thehigh-velocitywindofthecompactobjectarisingduring Hgamma HeI 4471 4 HeI 4713 y it 3 s n e t n e i v ti a el 2 R 1 -400 0 400 Heliocentric RV (km/s) FIGURE 5. The profiles of the Hg, HeI l 4471, and HeI l 4713 lines on November 17, 2000. The positions of the two componentsofheliumabsorptionaremarkedwithdashedlines. the outburstandemitting the broadHg emission componentcollideswith the disc in the regionof the orbitalplane anditsvelocitydecreases(Fig.1).Athigherstellarlatitudesthisvelocitydoesnotchange.Thiscausesopticallythick disc-likeshelltoform,whichoccultsthecompactobjectandplaysaroleofobservedphotospherewithaneffective temperaturemuchlower[13,14]thanthatofthecompactobjectinthequiescentstateofthesystem.Asaresultofthe velocitydecreasethedensityoftheoutflowinggasincreasesandthispartofitwhichisprojectedontothephotosphere givesrisetoareversalintheemissionprofileofHg andtoPCygabsorptioncomponentinthelinesofHeI. Wesupposethatthelinespectrumofanysystemcontainingindicationsoftwo-velocityregimewindoutflowcanbe interpretedintheframeworkoftheideaforaccretiondiscsurroundingtheoutburstingcompactobjectandpreventing thewind. 3.3. The 2006–2007outburst During the major 2006 outburst the Hg profile of Z And was multicomponent one indicating all regimes of the outflow in the system and to illustrate the interpretation of its line spectrum we will use only the Hg line. The Hg linepresenteda broademissioncomponentwith lowintensityandFWZI of∼1000kms−1 in additiontoitscentral narrow componentwith a nebularprofile. The broad component is best seen on the spectra taken after October31, 2006(seeFigs.6and 7).Thedataobtainedinthisperiodoftimeshowthattheenergyfluxofthebroadcomponent decreased when the light weakened after its maximum, whereas the behavior of the central narrow emission was different[18]. The broadcomponentwas analyzed by fitting with a Gaussian function(Fig. 7) [18]. On the spectra taken in July–September the blue wing of the broad component was not seen because of blending with the P Cyg absorptioncomponent(seebelowandFig.6).OnthespectratakeninOctoberandDecemberthebluewingappeared tobelessextendedthantheredoneduetoblendingwiththePCygabsorption.Weconsiderthatthebroademission componentindicatesanopticallythinstellarwindwithahighvelocityof∼500kms−1fromthecompactobjectinthe 8 7 Jul 8 Jul 9 6 Jul 14 Jul 20 t 5 s n o c Aug 13 + 4 x u Sept 7 l F Sept 8 g 3 o Oct 3 l Oct 4 2 Oct 31 Dec 1 1 Dec 2 Dec 30 0 -2000 -1000 0 1000 2000 Heliocentric RV (km/s) FIGURE6. TimeevolutionoftheHg lineofZAnd. system. On the spectra taken during July–September 2006 the central narrow component of the line had positive radial velocity, which was due to the presence of a blueshifted P Cyg absorption (Figs. 6 and 7). In July this absorption presented multi-component structure and occupied a velocity range from ∼100 to 1500–1600 kms−1. After that it gradually weakened and converted in low-velocity absorption presenting in the spectrum until the beginning of October2006(Fig.6).TheresidualintensityofthisabsorptionwasminimalinthemiddleofJulyat0.4.Asthecool giant’scontinuum,atthesametime,waslessthan9percentofthetotalcontinuumofthesystematthewavelength position of the B photometric band [8] which is close to the Hg line, the P Cyg absorption may be related to the opticallythickmassoutflowfromtheoutburstingcompactobject. The comparison of the spectra taken on July 9 and October 31 shows that the red wing of the broad component on the two spectra coincide (Fig. 7), which suggests that the Hg line has three components, consisting of a central narrowemissioncomponent,abroademissioncomponentwithlow-intensityandmulti-componentPCygabsorption occupyingbroadregionofvelocitiesoftheoutflowingmaterial—from∼100to1500–1600kms−1. The comparison of the Hg profile with those of Ha and Hb taken on September 8 (Fig. 8) shows that the Hg linehassatelliteemissioncomponents,too,withvelocitiesveryclosetotheHa andHb velocities.BothHg satellite componentswere observed only in Septemberwhen the intensity of the Ha componentswas maximal. In October onlyablueshiftedHg emissionpresentedinthespectrum.ThismeansthatinSeptembertheHg profileconsistedof fourgroupsofcomponents. The Hg profile is considered in the light of the second variant of the model (Fig. 2) where a disc-like envelope surroundingtheaccretiondiscexistsinthesystem.Thefour-componentlinecanbeinterpretedinthefollowingway. Thehighvelocitywindindicatedbythebroademissioncomponentcollideswiththediscanddisc-likeenvelopeanda collimatedoutflowformsafterthecollision.Theoutflowinggaswhichisprojectedontotheobservedphotosphereof theoutburstingcompactobject(thedisc-likeshell)givesrisetothePCygabsorption(Fig.2).Duetothisabsorption thebluewingofthebroademissioncomponentisnotseen.Theradialvelocitiesintheareaofthewindprojectingonto 1.5 y t i s n Oct. 31 e t n i e 1.0 v i t a l e R 0.5 July 9 -2000 -1000 0 1000 2000 Heliocentric RV (km/s) FIGURE7. TheprofileoftheHg lineonJuly9andOctober31.TheGaussianfitofthebroadcomponent isalsoshown.The levelofthelocalcontinuumismarkedwithadashedline. theobservedphotospherecoveranappreciablerange—fromvaluesclosetozerotothemaximalobservedvelocityof thecollimatedoutflow.Thisprovidespossibilitybroadabsorptiontoform.Theredwingofthebroademissionisseen since some part of the back wind componentis not occulted by the observedphotosphere(the disc-like shell). The high-velocitysatellitecomponentsariseinmoreouterregionsofthebipolaroutflow. Halpha 2 y blue red t i s n e t n i Hbeta e v i t a l 1 e R Hgamma -1000 0 1000 Heliocentric RV (km/s) FIGURE 8. The profilesof the Ha , Hb , and Hg lines of Z And based on a CCD frameon September 8, 2006. The satellite componentsarepointedwithverticallines.Thelevelofthelocalcontinuumismarkedwithadashedline. Wesupposethatthelinespectrumofanysystemcontainingindicationsofbothstellarwindandcollimatedoutflow canbeinterpretedintheframeworkoftheideaforcollimatedstellarwind. 4. THE SPECTRAL VARIABILITY OFOTHER CLASSICAL SYMBIOTIC STARS 4.1. HEN 3-1341 The Hen 3-1341system consists of a coolgiantof spectraltype M4 [2] withoutcircumstellardust[19, 20], very hot and luminouswhite dwarf with effective temperatureof ∼1.2×105 K and luminosity of 3.8×103 L⊙, and an surroundingnebulapartlyphotoionizedbythewhitedwarf[21]. FIGURE9. TheVlightcurveofHen3-1341overthetime1990–2005showingthe1998–2004outburstfromthepaperofMunari etal.[21]. Thesystemunderwentalargeoutburstlastingfrom1998to2004(Fig.9)whichwasitsfirstoutbursteverrecorded [20,21].High-resolutionspectraldatawereobtainedbyTomovetal.[20]andMunarietal.[21]duringthisoutburst. The data of Tomov et al. [20] taken on June 8, 1999 shows that the Ha line had an emission profile consisting of an intensivecentralsinglepeakedcomponentandadditionalsatellite componentswith velocityof about800kms−1 on both sides of the centralemission. The same appearancehad the Hb profile whose satellite componentshad the same velocity. The profile of the triplet HeI l 5876 line was similar to those of the Balmer lines consisting of the samecomponentsbutthislinecontainedtwo-componentPCygabsorptioninadditionwhichoccupiedbroadvelocity range—fromabout150 to about700 kms−1 (Fig. 10). The high-velocityemission satellite componentsof all lines were attributed by the authors to bipolar jets and the HeI P Cyg absorption was recognized as signature of mass outflow (stellar wind)from the outburstingcompactobject. Munariet al. [21] paid attention to the tightcorrelation betweenthestrengthoftheHa satellitecomponentsandtheHeIPCygabsorption.Theycametotheconclusionthat thewindplaysaroleoffeedingmechanismforthebipolarjets. In our opinion the correlation between the Ha satellite emissions and the HeI absorption of Hen 3-1341 is of primaryimportance.Accordingtothemoderntheory,theexistenceofbipolarcollimatedjetsissupposedtobedueto thepresenceofmagneticdiscwhichtransformsthepotentialenergyoftheaccretingmaterialintokineticenergyofthe outflowinggas.Thismeansthattheaccretingmaterialprovidesthejetoutflow.Ifweobservesimultaneousindications ofbipolaroutflowandstellarwind,accretionandstellarwindfromthewhitedwarfshouldhappenatthesametime. ToavoidthisdifficultyweuseanothermodelfortheinterpretationofthespectrumofHen3-1341,namelyonewith collimatedstellarwind. IntheframeworkofthismodeltheHeIl 5876linecanbeinterpretedinthefollowingway.Thestellarwindfrom thewhitedwarfcollideswiththediscanddisc-likeenvelopeandabipolarcollimatedoutflowformsafterthecollision. Theareaofthewindwhichisprojectedontotheeffectivephotosphereoftheoutburstingcompactobjectgivesriseto thePCygabsorption.Theradialvelocitiesinthisareacoveranappreciaterange—fromvaluesclosetozerotothereal windvelocity(Fig.2).Thisprovidesthepossibilityabroadabsorptiontoform.Thehigh-velocitysatelliteemissions ofalllinesappearinmoreouterregionsofthewind,notprojectingontotheeffectivephotosphere. TheHeIprofileofHen3-1341iscomparedwiththeHg profileofZAndinFig.11.Itisseenthegreatidentityof theseprofileswhichgivesusareasontointerpretthemintheframeworkofthesamemodel. FIGURE10. TheprofilesoftheHa ,Hb ,andHeIl 5876linesofHen3-1341basedonCCDframesonJune8,1999(fromthe articleofTomovetal.[20]). 4.2. BF Cyg ThesymbioticBFCygsystemisaneclipsingbinary[22]consistingofalate-typecoolcomponentclassifiedasan M5IIIgiant[23],ahotcompactobjectwithtemperatureofabout100000Kandanextendedsurroundingnebula[24]. Itsorbitalperiodisabout757d,whichisbasedonbothphotometric[25]andradialvelocity[26]data. ThehistoricallightcurveofBFCygshowsthreetypesofactivity.Itcontainsoneveryprolongedoutburst,lasting fordecadesand similar to that of the symbiotic novae,severaleruptionsof an othertype such as those observedin =(cid:3)$QG +HQ(cid:22)(cid:16)(cid:20)(cid:22)(cid:23)(cid:20) +JDPPD +H,(cid:3)(cid:24)(cid:27)(cid:26)(cid:25)(cid:3) >2,,,@ )H,, \ VLW Q H QW YH(cid:3)L %OXH 5HG %OXH 5HG DWL HO 5 (cid:20) 1D, (cid:16)(cid:20)(cid:24)(cid:19)(cid:19) (cid:16)(cid:20)(cid:19)(cid:19)(cid:19) (cid:16)(cid:24)(cid:19)(cid:19) (cid:19) (cid:24)(cid:19)(cid:19) (cid:20)(cid:19)(cid:19)(cid:19) (cid:20)(cid:24)(cid:19)(cid:19) (cid:16)(cid:20)(cid:24)(cid:19)(cid:19) (cid:16)(cid:20)(cid:19)(cid:19)(cid:19) (cid:16)(cid:24)(cid:19)(cid:19) (cid:19) (cid:24)(cid:19)(cid:19) (cid:20)(cid:19)(cid:19)(cid:19) (cid:20)(cid:24)(cid:19)(cid:19) +HOLRFHQWULF(cid:3)59(cid:3)(cid:3)(cid:11)NP(cid:18)V(cid:12) FIGURE11. TheHg profileofZAndbasedonaCCDframeonSeptember8,2006andtheHeIl 5876profileofHen3-1341 basedonCCDframeonJune8,1999[20]. theclassicalsymbioticstarsandsuddenrapidbrightenings,lastingasmallportionoftheorbitalperiod[27].Thelast majoreruptionofBFCygbeganin2006andatthepresenttimecontinues(Fig.12). 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 9 V BF Cyg B 10 U e d u t 11 i n g a M 12 13 52000 52500 53000 53500 54000 54500 55000 55500 Julian date - 2 400 000 FIGURE12. TheUBVlightcurvesofBFCygduringitslastoutburst[28](Skopaletal.2012). We observedthe regionsof the Ha and Hb lines of the spectrum of BF Cyg on seven nightsduring2009June– 2012September.DuringthewholetimeofourobservationstheHa lineoftheBFCygsystemhadmulticomponent profile.Ithadcentralnarrowemissioncomponentwhichattimeswasdoublewithablueshiftedcentralreversaland verybroadwingswithalowintensityextendedtovelocityofabout±2200kms−1 fromthecenterofthelinewhose natureisratherunclear.ThesewingswereanalyzedbyfittingwithaGaussianfunction.TheHa linehadanadditional emission,whichafterMay6,2012containedtwopeaks,situatedoneithersideofitscentralnarrowcomponent(see Fig.13).ThecomparisonwiththeHb lineshowsthatthesepeakshadthesamewavelengthpositionof∼400kms−1 like the satellite componentsof Hb indicatingbipolarcollimatedoutflow(see below).Thatis why we supposethat thisoutflowgaverisetotheHa peakstoo(Fig.14).