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VII/227 A Catalogue of Galactic Supernova Remnants (Green 2001)
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A Catalogue of Galactic Supernova Remnants, 2001 December version
Green D.A.
<Mullard Radio Astronomy Observatory, Cambridge, United Kingdom (2001)>
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ADC_Keywords: Supernova remnants ; Milky Way ; Nonstellar objects
Abstract:
This catalogue of known Galactic supernova remnants (SNRs) is an
updated version of the catalogues of Galactic SNRs presented in detail
in Green (1984, 1988), in summary form in Green (1991, 1996), and on
the World-Wide-Web (versions of 1995 July 1995, 1996 August, 1998
September, and 2000 August). (Note that version published in Green
(1996) was produced in 1993.)
This 2001 December version of the catalogue contains 231 SNRs, which
is 6 more than listed in the previous version. The basic summary data
included in this catalogue for each SNR are its Galactic coordinates,
RA and Dec (J2000.0), angular size (in arcmin), type, flux density at
1 GHz, spectral index, and any other names. Notes on these parameters,
on possible remnants not included, and questionable SNRs listed in the
catalogue are given in the full version of the catalogue on the
World-Wide-Web. It should be noted that there are serious selection
effects which apply to the identification of Galactic SNRs (see Green
1991), so that great care should be taken if these data are used in
statistical studies.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
snrs.dat 89 231 Supernova Remnant catalogue
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See also:
VII/187 : the 1995 July version which was superseded by this catalogue
VII/210 : the 1996 August version which was superseded by this catalogue
VII/211 : the 1998 September version which was superseded by this catalogue
http://www.mrao.cam.ac.uk/surveys/snrs/ : the on-line version
Byte-by-byte Description of file: snrs.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- SNR *SuperNova Remnant designation
14- 15 I2 h RAh *Right Ascension J2000 hours
17- 18 I2 min RAm *Right Ascension J2000 minutes
20- 21 I2 s RAs *Right Ascension J2000 seconds
24 A1 --- DE- *Declination sign
25- 26 I2 deg DEd *Declination J2000 degrees
28- 29 I2 arcmin DEm *Declination J2000 arcminutes
31- 35 F5.1 arcmin MajDiam *Major Angular Size of remnant
36 A1 --- --- [x]
37- 41 F5.1 arcmin MinDiam *? Minor Angular Size of remnant
42 A1 --- u_MajDiam [?] Uncertainty flag on Angular Size
44- 45 A2 --- type *[CFS? ] Type of remnant
47 A1 --- l_S(1GHz) [>] Limit flag on S(1GHz)
48- 53 F6.1 Jy S(1GHz) *? Flux Density at 1 GHz
54 A1 --- u_S(1GHz) [?] Uncertainty flag on S(1GHz)
56- 59 F4.2 --- Sp-Index *? Spectral Index of integrated radio emission
60- 61 A2 --- u_Sp-Index *[?v ] Uncertainty and variability flag on SI
63- 89 A27 --- Names *Other names commonly used
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Note on SNR:
This designation is based on the galactic longitude and latitude of
the source centroid quoted to the nearest tenth of a degree. (Note:
in this catalogue additional leading zeros are not used.)
Note on RAh, RAm, RAs, DE-, DEd, DEm:
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 for RA and DEC respectively. For
the larger remnants they are rounded to coarser values. They are in
every case sufficient to specify a point within the boundary of the
remnant. These coordinates are generally deduced from radio maps
rather than from X-ray or optical observations, and are J2000.0.
Note on MajDiam, MinDiam:
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
modeled 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 the full catalogue entry), although an angular size
is still quoted for information. For `filled-centre' remnants the size
quoted is for the largest extent of the observed radio emission, not, as
at times has been used, the half-width of the centrally brightened peak.
Note on S(1GHz):
The 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.
Note on Sp-Index, u_Sp-Index:
The spectral index is {alpha} where S({nu}) {prop.to} {v}^-{alpha}^
The spectral index of the integrated radio emission from the remnant
is either a value quoted from 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 the spectral index varies across the face of the remnant or
that the integrated spectrum is curved, and in these cases the spectral
index includes the 'v' in u_SI. 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.
Note on type:
S remnant shows a shell radio structure
F remnant shows a filled center ('filled centre') radio structure
C remnant shows a composite or combination radio structure
S?, C?, F? if there is some uncertainty
? object is conventionally considered a SNR although its nature is
poorly known or not well understood.
Note on Names:
Other names commonly used for the object. These are given
in parentheses if the remnant is only part of the source.
For some objects, notably the Crab Nebula, not all common names
are given.
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Remarks:
The on-line version on the World-Wide-Web contains much more
information on the individual objects, include many references.
History:
* 10-Feb-2002: Prepared by Dave Green [MRAO]
References:
Green, D.A., MNRAS, 209, 449 (1984) =1984MNRAS.209..449G
Green, D.A., ApSS, 148, 3, (1988) =1988APSS..148....3G
Green, D.A., PASP, 103, 209 (1991) =1991PASP..103..209G
Green D.A., 1996, in Supernovae and Supernova Remnants, (the
proceedings IAU Colloquium 145), eds McCray R. & Wang Z.,
(Cambridge University Press), p419.
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(End) Dave Green [MRAO] 10-Feb-2002