Redalyc.Very Large Array Observations of Winds from Massive Stars

Revista Mexicana de Astronomía y Astrofísica ISSN: 0185-1101 [email protected] Instituto de Astronomía México

Contreras, M. E.; Montes, G.; Wilkin, F. P. Very Large Array Observations of Winds from Massive Stars Revista Mexicana de Astronomía y Astrofísica, vol. 40, núm. 1, abril, 2004, pp. 53-60 Instituto de Astronomía Distrito Federal, México

Available in: http://www.redalyc.org/articulo.oa?id=57140106

How to cite Complete issue Scientific Information System More information about this article Network of Scientific Journals from Latin America, the Caribbean, Spain and Portugal Journal's homepage in redalyc.org Non-profit academic project, developed under the open access initiative © Copyright 2004: Instituto de Astronomía, Universidad Nacional Autónoma de México R Morelia, Nacional the they cen and kno lengths and Barlo classic evista 2 1 tly Since Univ Cen wn ultra c homogeneous hemical can w , tro w massiv ersidad Mic electron (1975), Mexic Aut´ through ork violet winds b de hoac´ e onoma of studied Radioastronom comp Cyg observ estos traba results p densities, en Key duran assumptions para jetos p desviaciones there and parameters on of v ana e an, ariations Mic P osibles ossess 1. from radiation it star the anagia the la temp their VER de M INTR w hoacana de WR Wor OB2 flo osition. cada jo cuy sup te ob ´ El The as exico. exist ado M winds winds assumption hot for ws observ Astr winds ´ exico, presen erature, jetos asimetr la p mo ds: o free-free osici´ 147 & sizes, ODUCTION Y ossible No. in classical y massiv with uno 3 vien ob ultima ´ onom from delo allo ´ F ıa de ST P — deriv confirman of brigh ha the w LAR In on Morelia, elli ationally p that jects (WN8h+B0.5V). tamos 12 R ere y CYGNI, oseen to de v w these ARS: ´ San sp ıas, ST this constan e e de ´ est´ Astrof ıa (1975) flux c to amos degree e M. the (B5Ie, ectral t emission. eive us no treated of deviate b ellos. d stars ARS: mo whose GE andar y sources: un inhomogeneidades een ´ obtain ecada Nicol´ w E. a Mic resultados hot to vien Astr densities. se underlying d a ´ del ısica, EARL stationary y el vien FR at un t 2003 Con , and hoac´ are questioned indices as analyze comp LBV?) of ARRA Estos massiv based CYGNUS tos v tama of W for wind radio from para as comp elo estas a to OM de ´ Univ ısic ionized treras, an, ionization W OLF-RA P Un v Octob isotropic que Y-TYPE cit free-free orta estacionario, alue righ no, ˜ Hidalgo, a Cyg M the par´ on la These b ersidad and e til y ortamien These para , w y sup , p ´ exico. eha star, 40 MASSIVE stars. se a isotropic Y and ossible 1 WR emisi´ t el ABSTRA the ametros er v for re- como RESUMEN basic b in osiciones G. e- & (B1Ia, , mass vior y ´ desv ındice OBSER tres 53–60 OB2 13; emission YET hot y features the Mon 147 on — v assumptions. ´ to ıan deviates lo ac ariaciones asymmetries, loss fuen massiv libre-libre and last LBV), isotr´ NO. esp distin tes, nos c (WN8h+B0.5V). the 1998; 2002). emission ev of w Cherepashc ual Radio sumptions tions. b firm (2004) CT ST predice epte de een ell han er, tes rates ectral material 1,2 ARS: homogeneous confirm The from V decade. opico mass p blobs lo d evidence (1981), ST 12) to ermiten studied, e A since brillan from F. sido observ Cyg 2004 Con esp ob TIONS In al for en ARS el existence ionized y P — loss de lines y jects INDIVIDUAL erado. cl´ (Moffat . W w treras the mo la the OB2 cuestionadas. la h eac the the inhomogeneities Wilkin January homog asico ere tes: mo who uc ations vien e In ST for tasa rate b detectar densidad delo ha h k oth optical w are ving ha nonclassical standard not this ARS: v stellar No. tos deviations ork of (1990) wind. P found Se en e v & Rep OF M ´ de eneo. 1 e of observ & seem est´ obtained the ˙ v Cyg suggested ionizados alid, ha w estos with 22 of b Ro 12 from p Rob ortamos andar. p ork, een ´ erdida region, la MASS de ossible targets. Ho Abb winds WINDS that dr rep studied (B5Ie, to (B1Ia, Sin ationally mo v presencia ´ ıguez ert w vien Existen the flujo. rep arious radio detect ortado w from (WR147, ev ott, b del, radio e in and em eha orted de er, 1994). is En tos. to p se wind presen el inhomogeneities LBV?) some LOSS LBV), bargo, eaks the These Bieging, based 1999; these Estas observ viour masa these authors since basa time flujo (marginally) represen este flux que and ob- de to discrepancy (Skinner t cases sup basic Theoretically theoretically ations. Exter erp ha & t these v assump- Ch osed individ- e found et et blobs Ho urc has b as- on al. al. w- 53 h- e- . , © Copyright 2004: Instituto de Astronomía, Universidad Nacional Autónoma de México viations. in rep t 54 it with geneities ing WR b loss v that a emission 1997). that the sources: rate. rates mal an et the sev b a cal surface can et b w y ations erger et y binary v a een . 3 al. the Asso asymmetric al. Note. ery eral w orted Cyg P Source WR WR W V The The wind stellar b with wind. the rates, V as een He 147, these ariable e Ho Cyg e 1990, are ery the 1981; form ciated go due This 2002). m National presen ev hot National OB2 147 147 − at study w concluded system, the P lines mo uc can o a making firm usually In en ev exp Decon d Large v Th w winds 0.7, Cyg to h ariations 1994; S N stationary massiv er, v of del e Univ example t radio No. this in Con ariabilit as explain w us, ected the t migh should of blobs. evidence o stellar the the Radio 3.5, 2. Science t 80% , v is ersities w 12 where stellar treras the olv in Cyg pap Arra (Girard the Luehrs orbital deriv o v OBSER e emission v t that absence ery and ed order ariabilit and sets stars of b main are y er this Astronom of 0 WR 0.06 wind tak In 0 OB2 y e F size . ed suggests wind. . the there Inc. 06 [arcsec][deg] imp θ 04 winds, oundation. et explained w the a 0 a of (VLA) due fact, 6 e sw of 1997; . e discrepancy to × 7 & assuming non-classical V × × including star assumptions errors mo al. mass in cm in ortan under presen No. eeping · cm A an observ observ of 0 y has 0 · 0.05(22) determine Willson to is to . TIONS . · rotation. 03 y (P in del 03(32) Williams It 1996; in the an of of Georgiev asymmetric Observ a that accoun 12, A) of the trinsic b (42) t of are co has c this t including een in three b ations ed b hanging of optical the op y and new CONTRERAS, teraction ecause the observ a ∼ P w Williams erativ this 1987; X-ra the b atory detected binary e and classical SOUR wind t 0. een Cyg 0.37 0 0 In reliable 0.25 v wind of 00 are et WR brigh . p . VLA ariabilit NRA 01. & 13 19 presence tak [arcsec][deg] in θ ossible y e the v the 3 ed al. suggested is mass mass ariabilit prop teraction Williams . not Ko agreemen × × × luminos- 6 could × (Abb inhomo- wind en op 147. CE source. t surface system cm optical 0.21(120) O 0 0 case (1997) 0.30(110) classi- obser- enigs- . . et erated radio mass 12(103) ther- deal- 13(160) 3 from (P with osed y loss loss SIZES de- ott A) al. on b T in of of of y e t ABLE MONTES, a AND 0 0.46 0.49 0 . 6 2005+403 configuration ∼ 1999 1328+307 F hours observ ∼ During densities and observ tiv the a opacit flux sizes Astronomical in zenith follo terminal soft calibrating sume data order 2D-Gaussian pure BUST w F ha 1 . 24 [arcsec][deg] 22 or or eigh θ small tegrated cm. v 0. ely 6 1 × × Data CLEANed e w × × 00 second the w cm P densit FLUXES 2.54 2 & hour 0.35(163) are 0 uniform used (T t 0 ed w June 0.21(93) y to . to ed, ed. and During (P for . optical 12(176) and Cyg b = 19(29) eigh WILKIN correction the able dep first et A) ha of for v obtain standard while 0, w the y and for elo 0 The the reduction for flux and and v ting ∼ first endence run . een 28 and the 03 of e 2) season, 2005+403 Figures cit fit w 0. giving b depth eac minimized 2015+371: second. AIPS 0137+331 1.99 maps 00 Image eigh total oth and densities mJy imaging. for Natural y during only 2015+371 observing 4 NRA 36.6 Cyg sc to flux 9.0 9.7 h S v for for [mJy] hemes 0 alues ting all · ep source the . of 7 · VLA Septem the of 0 on-source at IMFIT angular 2005+403 · w O. atmospheric 1 OB2 densities o eac cm . 1 2 w 2 01 sources. the ere c . . the Pro τ w . 5 1 source, and w Amplitude 0.7, hs as and 2 observ A h (T ere: w A = and as the at according 1.35 run t ere ap cessing t for the second w pro obtained No. on able 0.1. b 24.5 preferred 0.7 3.6 Uniform p 5.9 8.0 9.3 3.5 2), 3.6, a pro er erture S resolutions exp phase v erformed 1.18 [mJy] all cedures 3 the tak arra ed elength, eac in . and w 12, w cm, 6 Distances 0 cm cedure. In 1) 3 while and tegration . e ected and cm as 0 0 0 three 09 en b 0 extinction h only . . . at first y this . ha 1 2 and 2 o System calibrators 0 1 w an efficiency calibrators w source observ otstrapp . w observing at to using from as w 6 06, v e (Figure 6 0.7, as e for as WR in ha trop sources w 22.1 10.8 cm resp for run 0.7 decon 4.2 6.0 obtained. cm, the Based determined using of a termediate in 2.01 [mJy] S used v y and WR the 6 ed time e 3.6, , differen cm. sizes w ospheric ectiv ∼ the 147 and editing, cm w applied (AIPS) using . resp source. ed 0 0 e v 0 0 and 3). e . . 0. olv . . (R 1 1 liter- wind 0 2 w w w ha 2 on run. 147, 00 “A” pre- flux and w w . F ely the ere 02, ere ere 1.5 05, ec- w O- ed v In as as or a a a e e t . © Copyright 2004: Instituto de Astronomía, Universidad Nacional Autónoma de México 60 IMA at Fig. ature of S-E. are times with magnitude. but and mass-loss tries WR WR Cyg P Source P µ 0.7 not Cyg Jy 1. GR they W Cyg Both the or

50 © Copyright 2004: Instituto de Astronomía, Universidad Nacional Autónoma de México © Copyright 2004: Instituto de Astronomía, Universidad Nacional Autónoma de México OB2 147 147 (Con cm. VLA b righ DECLINATION (B1950) DECLINATION (B1950) corrected eam 41 0415.0 37 5237.0 inhomogeneities with w µ relation are rates w 20 1556.65 N S e 11.5 12.0 12.5 13.0 13.5 14.0 14.5 33.5 34.0 34.5 35.0 35.5 36.0 36.5 Jy t 20 3053.35 Con No. treras eak maps − DERIVED can & 1 an b exp at eam tours Barlo 12 emission for see 56.60 in 53.30 6 of ected for deriv et α termediate 0.26 0.25 0.12 − cm, eac P a 0 1 56.55 . w for 53.25 7 T al. RIGHT ASCENSION(B1950) p the Cyg and − · h ABLE ossible − · ed (1975), 3 · to 56.50 P regions Cyg . ob 3,3,4,8,12,16,30,40,60,80 0 0 0 1996); 6 53.20 ARAMETERS eﬀects (e.g., . . . and − cm 10 04 13 b Cyg OB2No.12 ject b y 3,3,4,5,6,7,8 56.45 e 53.15 OB2 data − blob P 2 Cyg 0.63 0.18 0.50 correct P Cyg α 0.25 (T anagia allo are Skinner 56.40 these 6 cm 6 cm 53.10 3 of . able 6 No. OB2 w to − IONIZED w ∼ p 56.35 6 eigh 53.05 ed 0 0 0 ossible the 0 3 cm . . . 06 02 05 12 data, to . 2). & − 04 No. © Copyright 2004: Instituto de Astronomía, Universidad Nacional Autónoma de México © Copyright 2004: Instituto de Astronomía, Universidad Nacional Autónoma de México times us t et N-E 4 are (R F an [10 Our σ to elli 12 M 2.7 1.0 0.5 al. 20 1556.65 OBUST=0). asymme- ˙ ab 20 3053.35 together − order − 0 · in 0.6 at deriv WINDS . 5 · 7 (1975) o 3,3,4,6,8,10, 1998), v · M 1.0 0.4 0.2 v the times alues all cm e mJy

56.60 the 53.30 ed ] observ of wind, 70 b 56.55 corresp 53.25 OF RIGHT ASCENSION(B1950) eam µ ed Con as 56.50 Jy 53.20 MASSIVE − 20,40,60,80 kind (1998) mined from ha able found the flux our creased v ters 1996). the early sities observ da w Cyg OB2No.12 w 1 b ariations tours onding a 56.45 ell eam at 53.15 v ys. v This e elengths. first 2D observ (ionization P Cyg densit c as 6, of 3.6 cm 3.6 cm b their with 56.40 hanges 1980’s − 53.10 ed that een for flux Sev 3.6, 1 Gaussian one in b b time map B1 at eha y 56.35 on 53.05 P ed their times ST previous eral y are 1995 prop 3.6 ∼ and in densities , Ia P vior Cyg All when a © Copyright 2004: Instituto de Astronomía, Universidad Nacional Autónoma de México © Copyright 2004: Instituto de Astronomía, Universidad Nacional Autónoma de México with noise. in v ARS 3.1 b 70%, the star ariable cm time Cyg as explanations eha 41 0413.4 37 5235.4 0.7 degree, osed, the maps 20 1556.53 long-term . v 60 has fits. are alues Cyg 13.0 13.1 13.2 13.3 34.8 34.9 35.0 35.1 35.2 35.3 12.9 and large vior. v has cm, P Abb ∼ µ ones, ariations 3. sp sho scale 20 3053.23 Jy − at b Cyg w radio but Comparing − 35%, OB2 ectral RESUL een 3,3,4,6,8,10,15,20,40,60,80 b resp ere ws ott (Con 56.52 wind 3,3,4,5,6 as b 0.7, een In eam w probably (B1Ia, none obtained observ ∼ e ectiv imp No. et deep this emission. and 53.22 studied RIGHT ASCENSION(B1950) 56.51 treras 3.6, found related indices v − of 50% al. TS elo 1 ortan 12 ely , times of w 20 ∼ 53.21 and − cit ed 56.50 radio (1981) LBV) Cyg OB2No.12 ork these . map 3,3,6,10,20,40,60,70 them 34%, that without using et − In as y in b (Con to t , y 6 50% 0.7 53.20 Radio al. w mass-loss 56.49 the c radio P Cyg 0.7 cm short at wind Skinner hanges cm, study new e they 0.7 cm resp AIPS rep mJy seems 1996). treras 6 ha 3.6 frequen 53.19 56.48 cm, consider- v based orted flux since emission as parame- ha ectiv . e cm b routine eam deter- v to in a They to et times et rate) e This den- map few ely the de- the for tly its al. on al. 55 − fit 1 , © Copyright 2004: Instituto de Astronomía, Universidad Nacional Autónoma de México found tinct emitting the 10 Fig. 56 − in dex altered star, sp b Skinner mal sp one lengths the one p abilit at of are (2001) serv to cen 6 seems again lations Genderen, lengths eha o 3,3,4,6,8, termediate cm ectral ectral 00 orly these 0.7 c tly Regarding Regarding hanges ed star, observing outer in v 2. wind. can close vior y arying regions is maps, , the to t cm radius) in correlated has long-term w ha VLA that b © Copyright 2004: Instituto de Astronomía, Universidad Nacional Autónoma de México almost sample b et regions index, new y o index, ha exp seems is eing v

the DECLINATION (B1950) prop region to the o 10,15,20 differen 40 1041 e The Sterk al. b v in consisten curring P data sho with e een CLEANed describ ect around studies, zero. 20 3454.1 outer 35 36 37 38 39 40 a (1998) decrease Cyg sp a morphology the osed more presen coming 0 to flat wn to non-isotropic differen coming en, observ rapid ectral . that w of 7 optical or a t the eigh b wind times − undergo in ed v in completely explanations & regions e (T the In en t ob alues P ts 3 prop the it south 54.0 flux Fig. t de able . with the tirely c v maps from 6 ed indices, Cyg: viously of t a our (R hange arious from nebula w parameters. 0.6 cm photometric regions Gro sp the opp ould osed, at OBUST=0). , corresp inner 1. es densit RIGHT ASCENSION(B1950) 53.9 2) of w of the ectral mJy case regions sp of uncorrelated. the other ot e 0.7 osite: wind whic a In the the while in ectral t b WR presen elongated Skinner differen since sho yp 0.6 region (2002) e 53.8 region, inner b these cm y men in the the WR onding eam h index useful es wind. w at ws c CONTRERAS, v 147 the farther the could hanges flux a alue the of index tioned differen t v sp all wind studies 53.7 − Th WR 147 star. a region Con elengths. t maps, closer and 1 0.7, at 0 et ectral stellar wind, but of time-scale), sp three us, . densit 3 6 cm to at Wind to 7 for at . b 0.7 tours al. 6 ectral Then, 53.6 0.8 − has out e 6 emission de examine 3.6, t ab ma − in not t w 0.7 related a (ab and b 3 P (1998) to and w w o . y index Jager (eac o y while oscil- 6 ther- 6 y from b v view . are v a a Cyg 53.5 and dis- v Re- ari- een out the ob- e. v v cm cm cm in- As w 0.7 an b 6 e- e- h e e © Copyright 2004: Instituto de Astronomía, Universidad Nacional Autónoma de México − MONTES, cm. 3,3,4,6,8,10,15,20,40,80,100,150,200 cm, 40 1038.0 20 3453.89 Maps resp 37.0 37.1 37.2 37.3 37.4 37.5 37.6 37.7 37.8 37.9 y the asymmetric 1998. 1 p sults emission one. 0.7 et somewhat wind more lar the where observ inner ∼ ula can ten termediate emission ing NE men denser from is et ortan − more 16 al. ectiv 53.88 ths wind The to to of w cm tary 1999 around hardly 3 error, & − ere the P (1996), of detailed is nebula × P ed Since its b t 53.87 90 than ely of 18 WILKIN Cygni’s also e ob flux Skinner decrease Cyg. deriv 10 source. obtained 00 at at cen . wind con ma 00 explained. mass-loss an . 53.86 vious − In lo in and see scale a v the Although structure 5 P our inhomogeneous. tral RIGHT ASCENSION(B1950) jor/minor w tamination densit is arious arcsec (as ed 4 the 53.85 study This diameter er M σ asymmetry Cyg still what surrounding -lev in wind t also

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(WR alues 3.6 the w ma e w as enhanced is ell b some Th ha yp (B5Ie, a w observing The ould Both b a e fit, standard while increased v W flat 2003), region fluxes It jor-to-minor for ob map een S v ts cm if case. elengths; is e and explained us, an as t on smo obtained e and b atson comp of star) IONIZED 2 viously the from ∝ clearly for w with y and one (Williams y 3 caused v w v rep b inhomogeneities the and the (Figs. e its . alue Con 0.7 ariation whic the ∼ n oth 6 a sho LBV?) deviation e ha emitting Since WR v source e 2 are curving − and of some orted onen elengths elongated , 18%, morphology emission et sho the wind a v 3). ws and second treras 0 assumption w 6 b of h o run e the . sho 2D it y 7 v elongated e al. 1 sho the cm from as ws 147S obtained al WR our − 0.3 that classical free-free t). 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WR al. al. the v made 1996 1996 the Morphologically Guna e discussed cm er treras presen cause 3.6 southern whic e densit v clearly 0.1 run, w of of flux and sets. the (1997) for t ariations remained A al radio (2002) the (2001) comp MERLIN inside rep in ations eak & wind at 1), with v flux 147S. inhomogeneities w WR w cm b precise of resolution. ariations mJy h w v v Ro the obtained measuring e 1995 e er orts b the WR measured alue. alues. resp densit quite t y comp an ST & emissions, w ∼ traces ecause Although confirm . still onen dr densit asymmetric. flux comp w e 3, and the of the 147S sho As E-W Ro ARS 3 find of same and Therefore, ork et b ´ source, ıguez cannot an ectiv 147N, y observ 1999). v yr. 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This a o -2.0 and t that north-south blobs What (2002) indices of p the Based w indices tak ossesses W p emission, b e (1999), clump R osition flux e eha they en exp do w OBUST=-1. of observ sho is ell ha vior on emission in are not ected v most w for v ariabilit seem with in e a based as June these a preferen ed, can sho suggested, exp whic the negativ the set those v surprising alue to an wn then ect of b S-W and to southern v h on y e y alues, lie Con fitting is at explained rep the in them tial for e of data it consisten Septem almost direction, index all tours T orted the the a south ma outflo able w classi- curv ab w tak to e com- y WR a t can out b v are w in- b b b en in es er e- 2. of w if y o e e t © Copyright 2004: Instituto de Astronomía, Universidad Nacional Autónoma de México assumption to greater the (2003) in of ters consisten will the latter under & b Raga c colliding with Although system. ratio b our (1996) northeastern adopt the ing jection to This v the ing with η tion, resp sev Williams the nation WR distance tion p view R This obtained hrotron ariations, y , o eak ◦ w w Ro P the eral agreemen Con the W from a stagnation stars. brigh wind e onds collision new normal neglect of of sho 147S, of ratio emission the new dr e but a the non-axisymmetric then = et b the the treras inclination to the for ha metho ´ p eing radio the v ıguez momen than b 3.4 c alues oin and 1350 t D al. maps, winds test est k the In north v to et from collision system. is repro assumption our exact v e calculated , the within . is Considering as t alue wings t t, 0. w the sho is inhomogeneities t 1997). and previously al. also w Fitting order the 00 thermal surface wing fit orbital indep & source d o 1999). part morphology w 556 o with and of φ of yr v tum w p collision duce the describ stars, ell (Raga c (1997). w alid Ro angle stars, oin solutions of estern k of stagnation = the WR supp φ e (v are error. app as angle has of dr v enden to no t. measure η φ In (Fig. loss 30 ratio an elo that the Along b ´ of the sp 0. ıguez stagnation and Giv emission. the the the 0. w differs If ecause 147N ◦ 00 b orted of apply ears obtained = et ed the 00 our cit t eeds. 020. der fitted et wing the w an 635 rates WR surface, curv the W morphology rederiv steady t en observ of al. w 30 pro o y orbital 3). used b R wind the Our of e of y of to (1999) een winds the estimated fit, ◦ fundamen ◦ is Huc the corresp w the stars obtain p b 1997). /D e Wilkin Can its . 147 jected an from and wind A of b the a eak η y Reasonable oin WR The plane 0. greatest is e , , the revised b e ed colliding line 00 w collision Our Th h sim for orbit thin and impro the isotropic p more y analytic p 020 and t t´ er = motion t e in parameters Bow angle o, are osition collide oin p of IONIZED 5 us, is the Doughert symmetry 2002), observ 147N onds sp assume ulated ossible sho η Giv 15 wind, η . assumption joining go (1997) Raga, of the b GHz 0.01, w t shell 1 in tal apply eeds separated Although = w o op v / ◦ orbital o Sho as is a c one w 2 tuitiv ed the en v at ould d at k / ≤ 0 angle alue surface en, wind to of parameters lo at head-on (1 tak (Con ed . relativ winds: mo sho surface agreemen ck fits radio but 02 the η a qualit mo images this are mass w whic & φ (see the the obtained sky that the the distance + suggest- y v er en e, ma del, b WINDS separa- c for Wilkin ≤ alue del is axis p to k, mo e is φ treras η . et latter m erio since stag- h driv- lo 0 limit from y , also, 1 ana- b that e syn- pro- cen- 30 y 40 also cor- still loss . uc / the the W the the the the y ca- del 01. for for w w 2 al. b to at of of of of ◦ ◦ ). h d a e e e e t , . OF MASSIVE rep tions. highly cal at & lution to detect information is than anisotropic that to t solv p lytic the b wind wind of sess most inhomogeneous could In comp previously a garding giv sho the confirms deriv angle standard error. sources. M.E.C, commen from Ciencias thank Program w ort o theoretical o o w Stapp a constrain non-classical e all this orted c All In W structure. ed inclination man same k a a w non-spherical the ed mo sho for in onen DGAP the e has φ of b region this fain observ higher a W Our giv line v v teresting the e of ys w thank of ariable ariations. dels previously ts a F.P y ers c e observ the the a ork, the B´ based for ks en surrounding b wind t north-south t direction confirm ST 30 our free w asicas from b clump emission. een on new emission and .W., NSF-In using A-P 2002). deriv a y ma suc the − +10 ed (Wilkin financial (north first WR ARS b wind y suggestion w 15 , Con o observ Luis sev This ed angle parameters source, rep y w e h our API on inhomogeneous. b wind w b winds. binary presen degrees the and ed eha est b a detect a (40864-F). crossing time sho eral elongation our star. treras 4. that v orted e momen W ternational but high source Ho mo new elengths from IT radio and generated F. v vior p fitting e of SUMMAR ed standard c 2000), source. ariabilit G.M. eak supp w preferen k wind new del found t b v systems. (IN107202) that is at ev the Ro ersions curv oth VLA angular P of ob t whic These maps at p observ & w of er, comp tum still lo with osition a at this ort. dr o Cyg jects to W VLA orbit. high Ro curv thank cated lo material. in Cyg e these ´ suc and ıguez p it is h F.P y atson that 6 WR w data attempt tial ossible to consisten for dr ratio, (see zone. its giv ations onen additional Researc due w mo er Y has blobs h cm deviates e of A ´ Additionally .W. are ıguez resolution angular ould the data. in OB2 as to corresp non-axisymmetric es resolution radio mo outflo del: Cyg financial highly 147 three confirm and for Gaensler, the et to t) b and its a η the clear those W northern een also dels of clumps , are b seems a lo al. (1999). 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