Äîêóìåíò âçÿò èç êýøà ïîèñêîâîé ìàøèíû. Àäðåñ îðèãèíàëüíîãî äîêóìåíòà : http://www.mrao.cam.ac.uk/projects/surveys/snrs-1996/table-0.ps Äàòà èçìåíåíèÿ: Fri Aug 30 15:26:15 1996 Äàòà èíäåêñèðîâàíèÿ: Fri Feb 28 18:02:43 2014 Êîäèðîâêà: Ïîèñêîâûå ñëîâà: m 103

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A Catalogue of
Galactic Supernova Remnants
(Version VI, 1996 August)
D.A. Green
Mullard Radio Astronomy Observatory
Cavendish Laboratory
Madingley Road
Cambridge CB3 0HE
UNITED KINGDOM
E­mail: D.A.Green@mrao.cam.ac.uk
Available on the World­Wide­Web at: http://www.mrao.cam.ac.uk/surveys/snrs/
1. The Catalogue Format
This catalogue of Galactic supernova remnants (SNRs) is an updated version of those presented in detail
in Green (1984, 1988), in summary form in Green (1991, 1996) --- hereafter Versions I, II, III and IV
respectively --- and on the World­Wide­Web (Version V, 1995 July). (Note that Version IV, although
published in 1996, was produced in 1993.)
This, the 1996 August version of the catalogue contains 215 SNRs (which is 21 more than in
Version V), with about thousand references in the detailed listings, plus notes on several dozen possible
or probable remnants. For each remnant in the catalogue the following parameters are given.
ffl Galactic Coordinates of the source centroid quoted to the nearest tenth of a degree as is
conventional.
ffl Other Names that are commonly used for the object. These are given in parentheses if the
remnant is only a part of the source. For some object, notably the Crab Nebula, not all common
names are given.
ffl Right Ascension and Declination of the source centroid. The accuracy of the quoted values
depends on the size of the remnant; for small remnants they are to the nearest few seconds of
time and the nearest minute of arc respectively, whereas for larger remnants they are rounded
to coarser values, but are in every case sufficient to specify a point within the boundary of the
remnant. These coordinates are almost always deduced from radio maps rather than from X­ray
or optical observations, and are for B1950.0.
ffl Angular Size of the remnant, in arcminutes, usually taken from the highest resolution radio
map available, although for some barely resolved sources that are thought to be SNRs the only
available size is that from Gaussian models after deconvolution with the observed beam size.
The boundary of most remnants approximates reasonably well to a circle or an ellipse; a single
value is quoted for the angular size of the more nearly circular remnants, which is the diameter
of a circle with an area equal to that of the remnant, but for elongated remnants the product of
two values is quoted, and these are the major and minor axes of the remnant boundary modelled
as an ellipse. In a few cases an ellipse is not a satisfactory description of the boundary of the
object (refer to the description of the individual object given in its catalogue entry), although
an angular size is still quoted for information. For `filled­centre' remnants the size quoted is for
the largest extent of the observed radio emission, not, as at times has been used, the half­width
of the centrally brightened peak.
ffl Flux Density of the remnant at 1 GHz in jansky. This is not a measured value, but that
deduced from the observed radio frequency spectrum of the source. The frequency of 1 GHz is
chosen because flux density measurements at frequencies both above and below this value are
usually available.
Version VI: 1996 August

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ffl Spectral Index of the integrated radio emission from the remnant, ff (here defined in the
sense, S / š \Gammaff , where S is the flux density at a frequency š), either a value that is quoted
in the literature, or one deduced from the available integrated flux densities of the remnant.
For several SNRs a simple spectral model is not adequate to describe their radio emission
because there is evidence that the spectral index varies across the face of the remnant or that
the integrated spectrum is curved, and in these cases the spectral index is given as `varies'
(refer to the description of the remnant and recent references in the catalogue entry for more
information). In some cases, for example where the remnant is highly confused with thermal
emission, the spectral index is given as `?' since no value can be deduced with any confidence.
ffl Type of the SNR, either `S', `F' or `C' if the remnant shows a `shell', `filled­centre' or `composite'
(or `combination') radio structure (or `S?', `F?' or `C?', respectively, if there is some uncertainty),
or `?' in several cases where an object is conventionally regarded as an SNR even though its
nature is poorly known or not well understood.
In the detailed listings, for each remnant, notes on a variety of topics are given. First, it is noted if other
Galactic coordinates have at times been used to label it (usually before good observations have revealed
the full extent of the object), if the SNR is thought to be the remnant of a historical SN, or if the
nature of the source as an SNR has been questioned (in which case an appropriate reference is usually
given later in the entry). Brief descriptions of the remnant from the available radio, optical and X­ray
observations as applicable are then given, together with notes on available distance determinations, and
any point sources or pulsars in the field of the object (although they may not necessarily be related
to the remnant). Finally, appropriate references to observations are given for each remnant, complete
with journal, volume, page, and a short description of what information each paper contains (for radio
observations these include the telescopes used, the observing frequencies and resolutions, together with
any flux density determinations). These references are not complete, but cover representative and
recent observations of the remnant, and they should themselves include references to earlier work. The
references do not generally include large observational surveys --- of particular interest in this respect
are: the Effelsberg 100­m survey at 2.7 GHz of the Galactic plane 358 ffi ! l ! 240 ffi , jbj ! 5 ffi by Reich
et al. (1990) and F¨urst et al. (1990); reviews of the radio spectra of some SNRs by Kassim (1989)
and by Kovalenko, Pynzar' & Udal'tsov (1994); the Parkes 64­m survey at 2.4 GHz of the Galactic
plane 238 ffi ! l ! 365 ffi , jbj ! 5 ffi by Duncan et al. (1995); reviews of Einstein X­ray imaging and FPCS
observations of Galactic SNRs by Seward (1990) and Lum et al. (1992) respectively; surveys of IRAS
observations of SNRs and their immediate surroundings by Arendt (1989) and by Saken, Fesen & Shull
(1992); and the survey of HI emission towards SNRs by Koo & Heiles (1991).
A summary of the data available for all 215 remnants in the catalogue is given in Table I.
The other names for SNRs are listed in Table II, and the abbreviations for journals, proceedings and
telescopes (both radio and X­ray) used here are listed in Table III. The detailed listings for each SNR
are given in Table IV.
2. Revisions and Notes
2.1 Objects no longer thought to be SNRs
The following objects, which were listed in Version I of the catalogue were removed because they were
no longer thought to be remnants, or are poorly observed (see Version II for references and further
details): G2.4+1.4 (see also Gray 1994a; Goss & Lozinskaya 1995; Polcaro et al. 1995), G41.9\Gamma4.1
(=CTB 73, PKS 1920+06), G47.6+6.1 (=CTB 63), G53.9+0.3 (part of HC40), G93.4+1.8 (=NRAO
655), G123.2+2.9, G194.7+0.4 (the Origem Loop), G287.8\Gamma0.5 (see below), G322.3\Gamma1.2 (=Kes 24) and
G343.0\Gamma6.0 (see below).
G350.1\Gamma0.3, which was listed in Version II of the catalogue, was removed as it is no longer
thought to be a SNR (see Version III for details).
G358.4\Gamma1.9, which was listed in Version IV of the catalogue, was removed, as following the
discussion of Gray (1994a), as it is not clear that this is a SNR.
In this version of the catalogue the following have been removed:
ffl G240.9\Gamma0.9, as Duncan et al. (1996) show that it is not a distinct SNR;
ffl G299.0+0.2 and G328.0+0.3, following improved radio observations, and comparisons with
IRAS data by Whiteoak & Green (1996) which showed that these are not SNRs.
Version VI: 1996 August

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The following objects, which have been reported as SNRs, but have not been included in any of SNR
catalogues, have subsequently been shown not to be SNRs.
ffl G70.7+1.2, which was reported as a SNR by Reich et al. (1985), but this has not been confirmed
by later observations (see Green 1986; de Muizon et al. 1988; Becker & Fesen 1988; Caswell
1988; Bally et al. 1989; Phillips, Onello & Kulkarni 1993; Onello et al. 1995).
ffl G81.6+1.0 a possible SNR in W75 reported by Ward­Thompson & Robson (1991). From the
published data (see the observations in Wendker, Higgs & Landecker 1991) it was noted in
Version IV of the catalogue that this is thermal source not a SNR, because of its thermal radio
spectrum, and high infrared­to­radio emission (see the subsequent discussion by Wendker et al.
1993).
ffl Green & Gull (1984) suggested that G227.1+1.0 as a very young SNR, but subsequent ob­
servations (Channan et al. 1986; Green & Gull 1986) have shown that this is most likely an
extragalactic source, not an SNR.
ffl A candidate SNR, G274.7\Gamma2.8, identified by Helfand & Channan (1989), has been shown not
to be a SNR by Caswell & Stewart (1991).
ffl G25.5+0.2, which was reported as a very young SNR by Cowan et al. (1989), although this
identification was not certain (see White & Becker 1990; Green 1990; Zijlstra 1991). Sramek
et al. (1992) report the detection of recombination lines from this source (also see Subrahmanyan
et al. 1993). Becklin et al. (1994) identify G25.5+0.2 as a ring nebula around a luminous blue
star.
ffl Most of the possible SNRs listed by Gorham (1990) --- following up SNR candidates suggested
by Kassim (1988) --- have been shown not to be SNRs by Gorham, Kulkarni & Prince (1993).
Some entries in the catalogue have been renamed, due to improved observations revealing a larger true
extent for the object (G5.3\Gamma1.0 is now G5.4\Gamma1.2; G193.3\Gamma1.5 is now G192.8\Gamma1.1; G308.7+0.0 is now
incorporated into G308.8\Gamma0.1).
2.2 New SNRs
The following remnants were added to Version II of the catalogue: G0.9+0.1, G1.9+0.3, G5.9+3.1,
G6.4+4.0, G8.7\Gamma0.1, G16.8\Gamma1.1, G18.9\Gamma1.1, G20.0\Gamma0.2, G27.8+0.6, G30.7+1.0, G31.5\Gamma0.6, G36.6\Gamma0.7,
G42.8+0.6, G45.7\Gamma0.4, G54.1+0.3, G73.9+0.9, G179.0+2.6, G312.4\Gamma0.4, G357.7+0.3 and G359.1\Gamma0.9.
The following remnants were added to Version III of the catalogue: G4.2\Gamma3.5, G5.2\Gamma2.6,
G6.1+1.2, G8.7\Gamma5.0, G13.5+0.2, G15.1\Gamma1.6, G16.7+0.1, G17.4\Gamma2.3, G17.8\Gamma2.6, G30.7\Gamma2.0, G36.6+2.6,
G43.9+1.6, G59.8+1.2, G65.1+0.6, G68.6\Gamma1.2, G69.7+1.0, G279.0+1.1, G284.3\Gamma1.8 (=MSH 10\Gamma53),
G358.4\Gamma1.9 and G359.0\Gamma0.9.
The following remnants were added to Version IV of the catalogue: G59.5+0.1, G67.7+1.8,
G84.9+0.5, G156.2+5.7, G318.9+0.4, G322.5\Gamma0.1, G343.1\Gamma2.3, and G348.5\Gamma0.0.
The following remnants were added to Version V of the catalogue: G1.0\Gamma0.1, G1.4\Gamma0.1,
G3.7\Gamma0.2, G3.8+0.3, G28.8+1.5, G76.9+1.0, G272.2\Gamma3.2, G341.2+0.9, G354.1+0.1, G355.6\Gamma0.0,
G356.3\Gamma0.3, G356.3\Gamma1.5 and G359.1+0.9.
The following remnants have been added to this version of the catalogue:
ffl G13.3\Gamma1.3 and G299.2\Gamma2.9, both identified from ROSAT observations by Seward et al. (1995)
and Busser, Egger & Aschenbach (1996) respectively;
ffl G286.5\Gamma1.2, G289.7\Gamma0.3, G294.1\Gamma0.0, G299.6\Gamma0.5, G301.4\Gamma1.0, G308.1\Gamma0.7, G310.6\Gamma0.3,
G310.8\Gamma0.4, G315.9\Gamma0.0, G317.3\Gamma0.2, G318.2+0.1, G320.6\Gamma1.6, G321.9\Gamma1.1, G327.4+1.0,
G329.7+0.4, G342.1+0.9, G343.1\Gamma0.7, G345.7\Gamma0.2, G349.2\Gamma0.1, G351.7+0.8, G351.9\Gamma0.9 and
G354.8\Gamma0.8, identified or confirmed as SNRs from the MOST radio survey of Whiteoak & Green
(1996).
Version VI: 1996 August

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2.3 Possible and probable SNRs not listed in the catalogue
The following are possible or probable SNRs for which further observations are required to confirm their
nature or parameters, or for which observations are not yet in the published literature.
2.3.1 Radio
ffl A possible SNR near the Galactic centre reported by Ho et al. (1985) from radio observations.
ffl Gosachinski–i (1985) reported evidence for non­thermal radio emission, presumably from SNRs,
associated with several bright, thermal Galactic sources (also see Odegard 1986, who questions
the reliability of some of Gosachinski–i's results).
ffl G300.1+9.4, a possible SNR nearly 2 ffi in diameter reported by Dubner, Colomb & Giacani
(1986) from radio observations.
ffl Routledge & Vaneldik (1988) report a possible faint shell SNR nearly 2 ffi in diameter at radio
wavelengths, near the young pulsar PSR 1930+22 (see also G'omez­Gonz'alez & del Romero
1983, who report a smaller (about 40 arcmin) possible SNR (G57.1+1.7) associated with this
pulsar, and see Caswell, Landecker & Feldman 1985 and Kovalenko 1989).
ffl G28.6\Gamma0.2, a possible SNR reported by Helfand et al. (1989) from radio observations.
ffl Seven possible remnants (G45.9\Gamma0.1, G55.2+0.5, G63.7+1.1, G71.6\Gamma0.5, G72.2\Gamma0.3, G83.0\Gamma0.2
and G85.2\Gamma1.2) of the eleven reported by Taylor, Wallace & Goss (1992) from a radio survey of
part of the Galactic plane. (One of the other possible SNRs reported by Taylor et al., G76.9+0.9,
has now been included in the catalogue, but is called G76.9+1.0, see above.)
ffl A faint, poorly defined possible remnant G41.1+1.2 reported by Gorham et al. (1993) from
radio observations.
ffl G9.7\Gamma0.1, a possible SNR report by Frail, Kassim & Weiler (1994) from radio observations.
ffl Ten (G355.4+0.7, G356.6+0.1, G357.1\Gamma0.2, G358.1+1.0, G358.5\Gamma0.9, G358.7+0.7, G359.2\Gamma1.1,
G0.3+0.0, G3.1\Gamma0.6 and G4.2+0.0) of the seventeen possible SNRs listed by Gray (1994b) from
radio observations near the Galactic centre (see also Dagkesamanskii, Kovalenko & Udal'tsov
1994, who from radio observations also suggest a SNR, G0.4+0.1, in the Galactic centre region
which presumably related to G0.3+0.0 suggested by Gray).
ffl G104.7+2.8, a possible SNR reported by Green & Joncas (1994) from radio observations. How­
ever, recent observations at 10.7 GHz (W. Reich, private communication) cast doubt on this
identification, as they do not support a non­thermal radio spectrum for the source.
ffl G310.6\Gamma0.2 and G310.8\Gamma0.4, two possible radio SNRs listed by Whiteoak, Cram & Large (1994).
ffl G11.2\Gamma1.1, a possible SNR listed by Kovalenko, Pynzar' & Udal'tsov (1994), based on unpub­
lished radio studies (Trushkin 1988, preprint).
ffl Duncan et al. (1995) list 10 large­scale (1.5 to 10 degree), and 22 smaller, low radio surface­
brightness candidate SNRs.
ffl Whiteoak & Green (1996) list sixteen possible SNRs (G308.4\Gamma1.4, G317.5+0.9, G319.9\Gamma0.7,
G320.6\Gamma0.9, G322.7+0.1, G322.9\Gamma0.0, G323.2\Gamma1.0, G324.1+0.1, G325.0\Gamma0.3, G331.8\Gamma0.0,
G337.2+0.1, G339.6\Gamma0.6, G345.1+0.2, G345.1\Gamma0.2, G348.8+1.1 and G350.1\Gamma0.3) from their
radio survey of much of the southern Galactic plane.
2.3.2 Optical/Infra­red
ffl G343.0\Gamma6.0 was listed in Version I as a SNR, identified optically by Meaburn & Rovithis (1977).
However, it was removed from the catalogue in Version II as its extent is uncertain, and it has
not been identified at other wavelengths (also see Bedford et al. 1984; Meaburn et al. 1991).
ffl A possible SNR overlapping G296.1\Gamma0.5, identified from optical (and X­ray) observations by
Hutchings, Crampton & Cowley (1981).
ffl A SNR (G260.4\Gamma3.3) about 4 arcmin in diameter within the Puppis A remnant identified
optically by Winkler et al. (1989). This has not been detected at radio wavelengths (Dubner
et al. 1991).
ffl A possible SNR (G32.1+0.1) reported from optical spectroscopy by Thompson, Djorgovski &
de Carvalho (1991), following up radio and infrared observations of Jones, Garwood & Dickey
(1988).
ffl G203.2\Gamma12.3, a optical ring about 3 arcmin in diameter, which was identified as a SNR by
Winkler & Reipurth (1992).
Version VI: 1996 August

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ffl G75.5+2.4, a possible large (about 2 ffi ) old SNR in Cygnus suggested by Nichols­Bohlin & Fesen
(1993) from infra­red and optical observations (see also Dewdney & Lozinskaya 1994).
ffl A possible optical SNR (G247.8+4.9) noted by Weinberger (1995), which may be Balmer dom­
inated.
2.3.3 X­ray
ffl H1538\Gamma32 a large X­ray source in Lupus, near l = 307 ffi , b = 20 ffi (Reigler, Agrawal & Gull 1980,
see also Colomb, Dubner & Giacani 1984) which is a possible old SNR;
ffl The Monogem ring, near l = 203 ffi , b = +12 ffi , is a possible old SNR (see Nousek et al. 1981;
Plucinsky et al. 1996, and references therein).
ffl X­ray emission in the Gum Nebula near l = 250 ffi , b = 0 ffi (Leahy, Nousek & Garmire 1992, see
also Reynolds 1976, Dubner et al. 1992 and Duncan et al. 1996) which, together with optical
spectra indicate a possible old remnant;
ffl an X­ray enhancement due to an old SNR in Eridanus near l = 200 ffi , b = \Gamma40 ffi (Naranan et al.
1976, see also Burrows et al. 1993 and Snowden et al. 1995).
ffl G189.6+3.3, a faint, possible SNR overlapping G189.1+3.0 (=IC443) identified by Asaoka &
Aschenbach (1994) from ROSAT X­ray observations.
ffl G117.7+0.6, a faint shell of soft X­ray emission near CTB1 (=G116.9+0.2), which contains a
pulsar (Hailey & Craig 1995).
2.3.4 Other
ffl G284.2\Gamma1.8 (=MSH 10\Gamma53), which was listed in early SNR catalogues, but subsequently rejected
because of its apparent thermal spectrum (see Version II for details). Ruiz & May (1986) report
optical and CO radio observations that indicate the presence of shock­excited material in this
region, supporting the SNR identification, although the parameters of any SNR are not well
defined.
ffl G287.8\Gamma0.5, which is associated with j Carinae, was listed in Version I as a SNR, but was
removed from the catalogue in Version II as its parameters are uncertain (see Jones 1973,
Retallack 1984, Tateyama, Strauss & Kaufmann 1991, and the discussion in Version II).
ffl G359.2\Gamma0.8 (the `mouse'), near the Galactic centre, which has been suggested as being analogous
to the central region of CTB 80 (=G69.0+2.7) by Predehl & Kulkarni (1995).
Finally, it should be noted that some radio loops in the Galactic plane (see Berkhuijsen 1973) may be
parts of very large, old SNRs, but they have not been included in the catalogue (see also Combi et al.
1995).
2.4 Questionable SNRs listed in the catalogue
As noted in Versions II and IV of the catalogue, the following sources are listed as SNRs, although, as
discussed in each case, the identifications are not certain: G5.4\Gamma1.2, G39.7\Gamma2.0 (=W50), G65.7+1.2
(=DA 495), G69.0+2.7 (=CTB 80), G318.9+0.4 and G357.7\Gamma0.1. The nature of G76.9+1.0 (an unusual
radio source similar to G65.7+1.2 (=DA 495)), and of G354.1+0.1 (which appears may be similar to
G357.7\Gamma0.1 (=MHS 17\Gamma39)) are also uncertain (see Landecker, Higgs & Wendker 1993 and Frail, Goss
& Whiteoak 1994 respectively).
There are also some objects that have been identified as SNRs and are listed in the catalogue,
although they have been barely resolved in the available observations, or are faint, and have not been
well separated from confusing background or nearby thermal emission, and their identification as SNRs,
or at least their parameters remain uncertain.
Acknowledgements
I am grateful to the many colleagues who have commented on the errors and omissions in previous
versions of the catalogue. No doubt errors remain in this version, and I am always happy to receive
feedback from users of the catalogue.
This research has made use of the Bath Information & Data Services (BIDS) ISI databse,
NASA's Astrophysics Data System (ADS) Abstract Service, and the SIMBAD database, operated by
CDS, Strasbourg, France.
Version VI: 1996 August

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Version VI: 1996 August