1996MNRAS.280..252D The Vela 2.4 Mon. A. 2Australia Accepted IPhysics As part 1 tic been surrounding extends Y, polarized observed 238°. Hoc brightest similar these plane. present 2 plane Details therein. data of The plane the Z INTRODUCTION OBSERVATIONS atlas R. Not. complex A presented GHz made. objects survey Department, equipment Vela of distances of many section Telescope 1995 in Duncan/ (Duncan R. area. of SNRs, the © the emission other Astron. November Rodgers Royal Maps remnant the (Duncan offer recent Parkes degrees (Milne supernova of National here and The large-scale (of Vela et Soc. and the a of 2.4-GHz al. University are close-up Astronomical observations the 1968) both 24. are et beyond 280, et Gum appears observing both R. 1955a), supernova Facility, Received al. al. order presented. 252-266 taken T. it and 1995a), nebula, (1960b), the structures of survey look and the CSIRO, sensitive Queensland, as of what Stewart,2 ABSTRACT frequency containing range. number the plane Sensitive, emission account individual: a Key west procedures from total-power 1995 section boundary remnant (1996) are 500 one the at remnants Vela and of as words: to PO The many September given also appear the 276°~1~238°, pc). Society the Gum identified These of along Galactic images a Box for of supernova are detailed 4072, of southern the falls region polarimetric larger of Lying in of a of features G 76, may our nebula this polarization R. (SNR) significant Table and the therefore to 2.4 the the 240.9 Australia observations largest Epping, 11 of within longitude be • and observations, from be so emission F. the Galactic Galactic features GHz. Vela-X, account linearly imaged Galac Provided 1. found close, ejecta lie - remnant, have are area Haynes NSW The and the the 0.9 with at the Both required. observations polarized identified 2121, - - from accelerated a were ISM: ISM: total-power latitude Gum Australia were by consisted tude radio sample a over the both 2 centre the Observations assumed Table rms and Bandwidth Nominal 3Cl38 0605-063 Observation Centre Telescope Hydra Rms 1934-683 Final made individual: The the Nyquist component bubbles beyond (I) separated an telescope, a Gum noises noise points map thermal are coverage and NASA Astrophysics frequency area nebula: discrete position-angle A 1. K. frequency by of using calibrator nns flux flux instrumental HPBW for Information, and HPBW scans are presented constant nebula. the rate). L. the - dates exceeding per noise by _5° Vela using quoted ISM: were the supernova polarized and is Jones shell SNR 4.0 beamwidth in of of ~ detected Maps values directions Parkes b a SNR arcmin, Galactic 2.417 a new +5°~b~ pol. performed individual: ~ for receiver of non-thermal G for -8° measured 8 for 1 a composed Vela, 0 240.9-0.9 beam - GHz. emission in the the explosion. 64-m as from perspectives (HPBW; supernova latitude 17 145 1994 1994 6 diameter. (10.'62 2.417 12 11.50 169° 11 ~ (8.'93 25.87 bandwidth of this observations. mJy/bea.rn 1 which area region roJy mJy mJy/bea.rn Data _8 % Briefly, using constant MHz Gum May March map (assumed) radio the Jy GHz Jy (measured) provided x /bea.rn /bea.rn x 0 of of 8.'40):1: is component are (assumed) (assumed) 10'.23) (b). over i.e., (_5° Gum 10.4 correspond System reinterpreted the these parameters, Radio of (+So Additionally, nebula the remnants. telescope, area of detected area Adjacent area area sampled Galactic arcmin. the Note ~ most 145 0.'08 Parkes :I: just observations nebula. ~ b (PI) 0.'07 © orthogonal (TP) (TP) (PI) ~ b emission MHz Galactic 1996 that ~ over -8°) - of of at -5°) above longi ISM: from scans and 64-m with the at RAS this this and two To as a a 1996MNRAS.280..252D were scans suppress 3 as full The Table the tion were region measured power procedures from Affected be from examined tionally, Instrumental the the although combined inverse Fourier beamwidth, ratio, smoothed-beam-area. 3(c) The 4 4.1 seen from and 1.2 of the power (PI) applied tary degrees north pulsar. Stewart about © Throughout First, Corresponding All Additionally, 1996 By To gain described faint DATA RESULTS times Baars bright description point-like Ve1a reduction images 2, has observations. region regularly in and Overview the the far were the 1. then the images the of images 270°, 0605 RAS, while and The Fig. transform. calibrators, individual to Note of & plane, and instrumental been low-level entire brightest SNR. areas the instrumental the the images et loop-like beamwidths (146 Stokes-Q using © eastern for Vela-X. either Haynes pertaining REDUCTION processed - appropriately structures 1.7 surrounding are 3. to smaller al. MNRAS in most subtle remnant, nominal effects Royal the that 063 sources is observed. and further Both procedures bad increase were the Jy Flux of and (1977) a 2.4-GHz shown Jy the software given AND of were later majority beam-I), the were the orthogonally scanning sections prominent scans Assumed side beam figures Large 1993) Finally, observations, polarized structures data features. while the these densities to either and SNR were 280, Astronomical Society calibrator G data-reduction to polarization smoothed in telescope resembling and and in flux polarization paper, smoothed approximately produce the observed of total-power DISCUSSION Hydra -I were 274.0 the survey Duncan the grey-scale is 252-266 arcs to points, Stokes-V images. will most 3C Puppis baselined, have map of of Vela, density combined corrected point-like in also signal-to-noise effects to add polarized Vela calibrator of the No intensity object of the in assembled polarized 138 -1.2 be A can improve will values resolutions, clearly noticeable up scanned emission been beamwidth which the the to and SNR. at spikes to with spatial et briefly A four 'plumes' Gum SNR scale. and and effects was to be to 2.0 maps be and and al. Galactic calibrate individual (G seen final 1934 or process source in 10 and enhance rescaled centred intensity used a image seen polarization calibration presented. Interesting visible (1995a). times noise. the values, also the nebula 260.4 - flagged is polarized G Gaussian outlined intensity such Jy and filtering into can maps in map where were - shown ratio or 265.1 each coincident beam agree point-like (see are signal-to-noise removed Figs within 638 G be shown the longitudes for the 'fountains' interference. maps. in a on the maps to 267.9 through images emission along detailed 3.4; were Reduction further. subtracted seen out. way were Table + Fig. -I 1 map the telescope required. below. well polariza has • in the are intensity mJy of visibility filamen sources and 1.5. images in several in Provided Milne, These Figs Addi in -1.1, width total to as 1. from used been with Vela with then total with seen H was will Fig. 1). per 2 the the an to in A of of II is is 1 The from extending centred throughout region nature related & emission Galactic This we pis enhanced in images. majority with G 1974). density been associated expected ized diameter iated by observations 4.2 by Both this remnant 1968, 4.2.1 The than represent to sion structure, from complex, of Triimper Features rounding sources. designations are Vela A Additionally, The Many The Fig. The Fig. 267.947 Whiteoak extend the the A are the some faint, frequency, total-power emission clearly faint the The that previously detected. the remnants, the with the 1980). of SNR radio Gum 3(a), The of dominant to observations integrated of l(b) looking on The NASA Vela plane of compact similar (Figs to are indicating bright Vela the A X-ray structure of Hoc exceeding the the circular these total-power much (1995). with features 146 several - with the compact total-power G visible. much be around Milne sky through nebula. 1.066 identifies and over brightest (from 1960a). Vela emission visible. can most Gum remnant. 260.1 Jy remnant and 1 many extragalactic. remnant with there Vela faint further objects image emission away image than angular and beam Astrophysics polarization be of Additionally, area sources the the degrees flux remnant (Caswell Faint sensitive (1980). of terminating appears nebula, Rodgers that + G sources this seen rms 8°. of filaments and are Throughout E The 2) to has 0.6. the brighter from and 243.2 Gum image - produced of point-like of presented the of Fig. out the in is J, the Furthermore, be are size, regions region can two noise Vela in Indeed, unpolarized large-scale previously is produced Vela the This not 'plumes' can this towards PI which more to much in than 2 Fig. visible wide-area SNR associated Vela bright & - consistent et small, be RCW nebula shows be the features 0.4 maps Vela reveals clear, sections and Haynes be in an figure correlates al. SNR (Sivan several 3(b), of by detected the associated covers source, by polarized form is a remnant more prominent and Data most seen order 1960a) in the spiral loop-like isolated 27 the cap-like can detected the SNR the by been Aschenbach, surrounding structure brighter but Figs and the emission a at correspond (Rodgers, image G remnant 1974). with low-intensity with 1987). Gum of the wealth are of objects in polarized extensive of be a north of System 253.7 region they 2.4 with arms, known. bright, was a contour l(a) much well are over the the Fig. presented emission Vela also with magnitude seen H the previous structure. areas nebula of in Vela-X, GHz features identified, However, can II SNR are and of found - with side a can total-power can the H an Hoc with 3(a), dominated larger complexes by associated regions Campbell 0.3. detail peak and in point-like the emission than II Egger be to possibly of 3(a) be angular SNR be far images sketch. (Milne of an region (Sivan Fig. polar assoc RCW seen. emis radio away those to Pup seen Vela Y, 253 here seen The area flux sur and less the Hoc the has are of be as at as & Z 1 1996MNRAS.280..252D
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The image is blanked wherever the polarized-intensity values fall below 0\ 0\ 20'. 1996MNRAS.280..252D 4.2.2 of X-ray ments' match region. most remnant Several Data the power features (Aschenbach 1 Gum Detection than © of 1996 Fig. the presence o ~ ~ Aschenbach prominently is I pertaining nebula features well remnant 1 image The RAS, of extensions seen ~~'~'~'~~~"~'~'~'~'~'~~~~~~~~~-.~.~'~"~"~'~"~:~::~':~:~:.~:'.:~:~::~:~::~.~::7:~::7::~:-.~::~:~:~T.~::~:.~.:~:~::~:~:~::~:T.:~;~::~:~::r:~::~:~::~:n shows will shell ,...... -- --- :!:::::::::::.::::. ::::::::::::; ...... : : : : : : : " ...... :~~:::::.:::: ...... _ ...... ::::::::::::: ...... :. ~ ...... :.:::".:.::: • the ...... ~ . . :.'.::. .. • • © of .. with ~ ,...... , Vela --_ ...... ~ ...... MNRAS ...... ~ ...... •• :.' • ...... · .. 275 · now ...... · the Royal from original et ',::.=.:.: ~ ...... and ~ on can of -. ,...... ~ : : • : : : : ...... feature identified ~ ...... similar is al. 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Figs .. • • radio considerably ::::::::::::::':":::::::::::::.:.:::.:':::::::::::.": : ; .. •..• C with : . • ...... • ...... , '" • • • • : of ...... "...... ,.,...... , ~ and ...... : ; in are ...... 1 as In :: ...... ~::::::::: ~ ~ . . :=::::::::.:: ::::::. . . .., " . ... • :::::::::.::: :::::: :: I Vela. emission ...... ,...... and •• . side ...... ••• our an Society sketch (F) , ...... " ...... , , ••• .. identified ...... ~ ...... emission ...... • • • • D high-velocity ;:;::'::: ... given ...... , ••• I'. .. the ~ ~ ... .: •••••••••• ... ,., ...... • • • • H ,...... ~ ~ ...... " , ...... and 2. Specifically, ...... :::::;::::::.:;:: ; : ,...... 2.4-GHz, 'f of is :.::.:.: ...... I : I : ...... ,...... ~ .. 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" ...... :::-;::: ...... • , :::::::;: ...... ,,,,...... "...... by complicated only. this region the from 'radio' our encompassing of ated in this spectral symmetric (Wright emission. feature computed. source ...... •• :::::::::::::::~:~~;;::::.:.::: ...... •••• .. Vela ~ . :: • .... •• ::~::;:':~ ~ ...... -_... , ...... Feature feature ::::;. _ :::::: ~ ...... the SNR the .. : ; ...... • .. • ...... 2.4-GHz region .... "., ...... ••••• ...... ::: :::::::::!:~J~~ ...... with object It _ ...... , ~ , . ~ :::::~::::::::::::: , the ...... ~ ·,,. , , ...... SNR (Fig. _ sections, - ~;;;;;-;~I; " :H1!; ...... :::::::;~~::::::::::::::: ...... should • source (1.05 _. B. index .. ::: et "·~::~§§~~lJ~ ...... NASA Astrophysics , - -_ ... shell. ,...... , ...... ::::: Especially RCW _ :' .. .. "" ...... " PMN ...... " A al. crescent (Strom ...... , . , ,., B This ~~~ ...... ,., ...... :::: ...... ,.",...... ••• f...... 1b), appears by - ...... is • and value ...... · can 1994), .. .. '1 .. ,...... beamwidths) - ...... "...... , .. · _...... ,...... be both ::::::::~::.: The too ". 265 ",. , ~ ... " -...... , .. oo catalogue the in _ ',.,."1'.'" with ...... 33. source data, feature 1.'._. , .... _...... noted ;.:.:.;;:: i! be .. ", ...... et the agreement great "1' shows ...... ,' with 'X-ray superposition it' :·;''ttli~~~~~~~:i oo...... ~ ,..... Nevertheless, segments and interesting al. ~~~: ,...... clearly the ...... '" ...... • real, .... and 0 • Gum :: ...... ••• 1995). that (G a - : : , C' a 0. to " A c ...... latter the well-defined '. comparison ::::::::::: ...... section' .. of ~ C obtain ...... , .. ::::::::::::::::: ...... is so with 265.14 '.'0','_ ::.::.:.::::::::: ...... near ~~§ITI·~Ir~ the . seen ...... " source divided with nebula ...... the The and no ...... is . • ::::::::::::::";:::::::::.:::: ...... • ...... section appearance ...... ::::::::: ...... faint ...... a the of an Data the spectral ...... in the of size + 4.85-GHz extending bright, , , " ,., .. to radio 1.45; ...... :.:::::: ,., , feature "...... accurate Fig. into "'" ... HI::::: ",." ...... , geometric VLA of radio at 'leading-edge' ofthe , ...... _ ...... have visible extended ...... , " , ...... the System - 2.4 ::::::::::::::::::: ...... "', .", , , .. ': " I l(a) both slightly ", ...... RCW ...... ",...... ::: :.~:::::;::~:::::: ...... •• , . . . emission index ...... ,. ... " ...... "" .... •• .. observations :::::::;:.;:::::: ...... , "...... counterpart • , • • . , . of listed a A ...... , 'radio ...... ••• I back PMN , 'I· ...... ::::::':.::::: GHz .... ". , "...... , ...... , I flux non-thermal in ...... , •••••• ...... : . " feature as was 'X-ray' """., ...... ; • ...... ' ... .. """ ,...... , ...... • ... . 260 36) centre ...... the ...... "...... has extended emission a flux . ,...... estimate ,. •••••••• I.,.t :::' towards section' ...... :...... located . associ , . I I I I , bright, ...... survey .. to ...... is radio been ::::: ,.. , • I .. .. . 257 with A , , .... •••• •••• and the the ...... ••• . ... of .. of ...... of . is ...... , ...... I . . . . , .. .. 1996MNRAS.280..252D
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~ @ o o ~ ~ 10 o o ?"'4 tl <-< ;::::: ~ 2 -> ;: ....[IJ .., ~ o o $:) o l"'- o= co ..:3 ~ ~ rJ1- o o ..~ o o (D co ~ '0 ::J • ....~ ~ (\j ~ ~ o -< o ~ ~ Q. ~ .... 10 ;- I o z o > N rJ1> > ....[IJ 8 "0 o ~@ 260 255 250 245 240 [IJ•• '0..... ~ '0 [IJ ~ Longitude ~~ ~[IJ ..... Figure 3. (a) Grey-scale image showing the total-power emission over Galactic longitudes of 238°:5;/:5; 260°; the region of the survey where the faint emission from the Gum nebula is most ~ :: rJ1Z easily seen. The grey-scale wedge is labelled in units of mJy beam - I. Axis markings are in degrees. (b) Grey-scale image detailing the polarized intensities detected over Galactic longitudes ~~ of 238°:5;/ :5;260°. The grey-scale wedge is labelled in mJy beam- I. Axis markings are in degrees. (c) Orientation of the polarization vectors (magnetic vector) of the received radiation over ;-[IJ the same longitude range as in part (b). The length of each vector is proportional to the polarized intensity, with a maximum intensity of 250 mJy beam - I. Axis markings are in degrees. The :3 ~ image is blanked wherever the polarized intensity values fall below 2er. •Q N VI N I N ~ ~ 1996MNRAS.280..252D © 1996 RAS © , MNRAS Royal 09e: 280, Astronomical Society 252-266 00e: 09l • Provided OOl The by Vela the SNR NASA 09 and Astrophysics the Gum o C,\l C,\l LO LO 0 ~ nebula ....:I +' ..... '0 Data ;:j I=l 0 btl CI) at ~ '" -;:: ~ = .. .. " System ::: ::: '" a v I 2.4 GHz 259 1996MNRAS.280..252D 260 third feature 36 circle density with Verma and order large (Whiteoak 36 of confirms beyond some appearing integrated the emission arcuate itudes, ± all is 4 calculated Another Feature The our is has emission X-ray arcmin. o 10 a unlikely, star-forming velocity I brightest suggestion centred 260 of A. high-speed data essentially a X-ray et B the of structure seen structure 30 velocity a .. . is al. R. - in ,,., ··." © just flux thermal & 24 C broken shell km that with object, Any 1994), associated our for , I . " Duncan Royal feature Gardner dispersions however, on can Jy is to ••• object S-I this is, ofthe from radio association the estimated dispersion the beam-I. 'fragment' at the .. ' region associated also into up spectrum. ,' (Caswell .. protruding the ··,1 object, PMN . Astronomical E bright the a east visible f within 1977). Vela image with as et I'" the edge appears in be II within this total-power (e.g. al. a The source of 'leading-edge' """ in \ since faintly the remnant, typical source would similar & I between ofthe Furthermore, feature can "' with in Table latter the .. Haynes ".... 255 Caswell feature north-east approximately the faintly Fig. we be brighter a dense list .... .,~ be map. for detected with manner source region, 2. cannot well D, is feature •• • 1, expected to image (Wright ... H Society 1987). feature at is __ ----~"~~ known No with an & II feature fitted detected. far molecular feature is any edge whereas regions, be to uncertainty ...... integrated Haynes that in a Band negative Comparison a that et certain known D. interaction as 45 by peak Fig. of D the • al. produce .. There D'. a B. ,.~ seen Figure arcmin and Provided of RCW X-ray RCW cloud semi 1994) 1987; radio l(a), -.".0: The H flux that flux lat the an of in II is 250 - 3 Longitude continued 4.2.3 large The remnant sion of edge intense complex tion towards total-power brighter power polarized unusual gential length. Polarization to known the reach rotation, by - see Like The estimate a formation the visible faint, ",.,,~"'''' is polarized of ,~,;~ Section amount values Polarization emission appearance at the magnetic in It over the the negative Vela NASA Astrophysics structure, - to as is low emission other broad, far total-power in the possible is remnant. a image, percentages the up 4.2.5) the emission. intensities probable in of more latitude of intensity overall SNRs, in SNRs, to associated Vela-X field the northern polarized polarized intensities the of 245 associated ~50 runs that comparatively than familiar Galactic Vela (in The size nature of image, This per we image parallel region, and along the this has © the be:::. half polarized ofthe in with 'arm' are 1996 cent. structure 'arm' across absence extends ,,--~""~ been 'shell' polarization region outer with ,,--. latitudes, much -7~5. of the of of detecting with the to RAS, which object. running The the Data of ... Vela arm the known the the , little regions structure, of arm ofthe emission polarization of most to remnant. Closer MNRAS direction associated northern arm ~la are the significant with is (Fig. approximately We System the emission is from before. can not very of polarized Vela over remnant of lost find early 240 the in, the which 2a) the also is understood. 280, As the patchy, of side within most SNR. especially the exception the with polariza is stages remnant shows with Faraday the be 252-266 is Vela-X a is bright of emis total most of used seen well tan the the the but the the its in a 1996MNRAS.280..252D emission Figure in remnant from cisely tion the faint graph north-east pass © degrees. 1996 bright image that 'arm' both than 4. is RAS, An (thick not shell The © derived outer in presents side overlay of this MNRAS completely Royal the Table features 1b). lines) 2.4-GHz polarization to D A A B C Feature fits arc polarization total-power (radio) (X-ray) be of from from 2. a the of the enclosed 280, Astronomical A, problem: contour polarized Integrated 2.4-GHz the fig. derived B, enclosed 252-266 (6±I)Jy (600 (4.5 (2.3 (0.8 C Integrated discussed 2 total-power co CD of and image. I I arm levels by ± ± ± ± at Dame total-power shell emission 1.0) 0.3) 1.5) D 150) far a fluxes by (see and circle are: However, 268 Jy Jy Jy negative the Flux et in o mJy boundary Society al. Fig. 0.65, a. Interestingly, map. the for match circle. on indistinguishable (1987); contours previous 1.5,5, the latitudes, off the To the more 0 see remnant's 266 • 0 polariza 10,50 surrounding encom Provided Section bright para pre the and Longitude 4.2.1. 100 The the 264 Jy by Vela which was polarized shell conclude The The that min expansion et maps the tely rically polarized seen (i.e., (1989) ray 0 Vela Vela beam-I. To al. the features convergence resolution elliptical away also length the must opposite in remnant 1995) region of the is SNR and into Fig. NASA Dame Vela noted extremely arc that CO from eastern emission be 262 the occurring - of the 2(a), discussed (Aschenbach in and (thin on of 8 emission the the the this SNR close ~ et shape, the from the 6 interstellar the point Astrophysics Vela al. has across lines), side the density minor CO positional pulsar from likely, opposite match 1987). and the a contours towards with in of Gum SNR of contours less 260 with and Section axis, the several pulsar recent Vela birthplace. enhancements et given a between As certain contours medium, must major centred X-ray side nebula al. difference estimated are such, negative is we 4.2.2. X-ray have 30 1995), the areas have in Data of detect axis fragments value arcmin. the the steps of the approximately As work with at velocity-integrated a Specifically, expanded of surrounding observations pulsar SNR it SNR, from a common Galactic System visible is of 2.4 of width large significant is Axis of the real. 5 K 5 (7.4±0.5t. reasonable is GHz (Aschenbach the Bailes position the markings approxima amounts km (8.6 most on Assuming asymmet emission latitudes remnant origin features S-I. the ± 40 the of offset et rapid 0.3t. 261 arc and CO the CO are X al. to of - 1996MNRAS.280..252D well, feature Band 262 nant which rounding significant ated cent in velocity percentages polarized The to the between possible seen 'radio' ation feature object 45 the ture pulsar. sects is of ment' be ing is along 4.2.4 A tion those position across 2.4-GHz the regions has of magnetic Vela, this netic field sion), of the magnetic-vector appear Associated An produced The curious map Unfortunately, polarization; the the First, arcmin the claimed. polarized centre edge' bright RMs. adjacent only direction 'line' across appears with at source confirming (well measure the was from of feature A. percentage Galactic where D/D' as may arc morphology sections), interesting Polarization the of B. G at significantly fragment of we features that the angles been feature emission, the results (apparent) of the R. a of 264.3 field. particle their of in to (the H © within the made to Vela the be might the latitude by appear of the are Vela polarized as II feature length, section this the note polarization Duncan lie with Royal expanding also. emission occurring traced performed remnant. particle object. area region emission plane. 2.7-GHz (RM) a over instead, + total-power If fragment; remnant that of approximately approximatly B CorE. vectors A to thin from itself. 'core' expect the supernova 1.5, polarizations acceleration as This that feature position rotation (Fig. polarized the and with of of to least draw rotated oriented of D, the path the back detailed uncertainty) Astronomical linear which Note this Note b RCW information have emission received acceleration a No seen features is B, the et where region approximately we 2a) However, percentages work = the from follow Vela-X shock confused synchrotron bright, indeed is from over position some around structure al. nevertheless, D towards + convincing angles arc, that see that shown is matches significant ( direction segment corresponds emission. explosion, 34 on 1 ~ approximately is structure of small this it ~ 45 multifrequency is is the the 45°), tangential compresses the just 7. radiation rise a (Caswell a is general a feature crosses A seen the region point-like Milne taking associated bright G The break per considerable terminated we angles the by Vela-X Vela feature in arc Vela-X, (both from to exists strongly 264.3 to while at the of north-eastern of other of Fig. along process can detection position linear the cent 20 The polarization fairly with the ~ Society (1980). this place. are polarized pulsar D' RCW the no 'core' in total-power conclusions can to yet (magnetic should 55 & arcmin + to use 2(b). west, the the over region, and this order H cannot association the polarized consistent the along the projected where PI 1.5. Haynes frequency, depolarization with perpendicular per implies section the another closely. II be is in the Polarization vectors 34. 'X-ray' to region of polarimetry mid-section structure image hence amount The position This the interstellar region of lie the the bright a cent. across, the the of emission the detected Again, • available most cap-like no polariz be it close vector) associ vectors side 25 of 1987). vector domi Provided that figure Along struc inter 'lead about 'frag high outer emis Vela seen mag rota near lying It with that sur and this per can lies rim the of of of in of to is is it it variations along if remnant, rad rotated ever, 4.2.5 rather bright, found The Although values vectors seen ing their place stantially ated determine our associated edge across fused feature value ports clear dominating lie ment ±26 pret. RM evidence a order radiation where Gum by (e.g. component 2.4 Hence the 8= age 8=0.8U (pc) thin caused Lerche This The The tangential. most data m GHz the path, O.71