2. The catalogue

The new edition of the Asiago SN Catalogue lists data for 1447 SNe and for their parent galaxies discovered up to 31 December, 1998. For the galaxy data we made large use of the Third Reference Catalogue of Bright Galaxies by de Vaucouleurs et al. (1991, [RC3]) and of the LEDA and NED databases.

   

Table 3: Supernovae not included in the ASC89

1945B	1975U?	1983ab
1950N?	1975V?	1985S
1950O?	1976O?	1985T?
1951J?	1976P?	1986P?
1953J?	1976Q?	1987Q?
1953K?	1977I?	1987R?
1953L?	1978J	1987S
1954ac?	1978K	1988ac
1954ad?	1978L?	1988ad?
1955Q?	1980Q	1988ae
1955R?	1982Z?	1988af
1955S?	1982aa	1988ag
1962R?

The format of the new edition follows that of ASC89 with some improvements. In particular, we have now included:

1.

Accurate supernova positions;

2.

Position angles of the major axes;

3.

Morphological type code of the parent galaxies.

Accurate SN positions are mostly useful to compare observations at different wavelengths, from X-ray to radio, which in recent years had a large impact in SN research. Note that in the present Catalogue all coordinates are given at the 2000.0 epoch. Major axis position angles were introduced to study the position of the SNe within the galaxies and numerical morphological type code to facilitate the derivation of descriptive statistics.

Instead, we choose to drop the information on the parent galaxy luminosity classes because this information is available only for a small fraction (less than 20%) of the objects. The galaxy integrated luminosity can be computed from the apparent magnitudes and distances of the galaxies.

To facilitate the consultation of the Catalogue, we present it with two different sortings: in Table 1 the list is arranged chronologically according to the date of SN discovery while in Table 2 the same data are listed in order of Right Ascension.

In the tables, the content of the different columns is as follows:

1: supernova designation. The symbols "?'' denote an unconfirmed SN and "*'' the occurrence of multiple SN discoveries in the same galaxy.

2: parent galaxy identification. In case a galaxy has different identifications, we adopted the following priority: NGC, IC, MCG (M), UGC, ESO (E), PGC, Leda, others. In some cases specific names are reported, e.g. LMC. Anonymous galaxies are listed with the letter A followed by the coordinates. In a few cases, where the association with a definite parent galaxy was not possible, we have filled the field with INTERGALACTIC.

3-4: equatorial coordinates of the parent galaxy at the 2000.0 epoch.

5-6: equatorial coordinates of the supernova at the 2000.0 epoch.

   

Table 4: Objects which turned out not to be real supernovae

1950E	1986F	1991W
1956C	1986H	1991ap
1967F	1987E	1992W
1973G	1987H	1993U
1893H	1988X	1993V
1985J	1990C	1998di
1986D	1992X

7: morphological type of the parent galaxy.

Figure 1: Histogram of the number of SNe discovered per year. The shaded area refers to SNe with magnitude at maximum (or at discovery) brighter than 14 which, enlarged by a factor 10, are also shown as dotted lines

8: morphological type code for the parent galaxy (coding as in RC3).

Figure 2: Distribution of SNe with the redshift of the host galaxy. The shaded area is relative to the SNe discovered in the last 6 years

9: only for disk-like system, inclination of the polar axis with respect to the line of sight in degrees (0 for face on systems).

Figure 3: Distribution of SNe in the sky in equatorial (top) and galactic (bottom) coordinates

10: position angle of the major axis of the parent galaxy (North Eastwards) in degrees.

11: heliocentric radial velocity of the parent in km s^-1, but for objects with redshift $z \geq 0.1$ where the z value has been listed.

12: integrated B magnitude of the parent, mostly from the RC3 or LEDA. In a few cases only photographic magnitudes (prefixed by "p'') are available.

13: decimal logarithm of the apparent isophotal diameter, in 0.1 arcmin units.

14-15: SN offset from the galaxy nucleus in arcsec, in the E/W and N/S direction respectively.

16: if available, supernova magnitude at maximum (photometric band indicated); otherwise discovery magnitude (labelled by "*''). A magnitude without band means that the observation has not been made in a standard photometric system (e.g. those reported in the discovery announcement as photographic, blue plate, red plate, CCD without filter, and so on).

17: supernova type, mostly from spectroscopy. In a few cases, marked by "*'', types have been inferred from the light curve.

18: if known, epoch of maximum, otherwise "*'' marks date of discovery.

19: name(s) of discoverer(s). For organized search teams the acronyms are given.