Summary

The morphological catalogue of galaxies, MCG, (Vorontsov-Velyaminov et al., 1962-1968), which presently can be considered as one of the most complete galaxy catalogues, has been used as a main source of data for the merged catalogue on the magnetic tape. It has been supplied with information from the other catalogues and lists of galaxies published by 1973, such as UGC (Nilson, 1973), RCBG (de Vaucouleurs and de Vaucouleurs, 1964), CGGG catalogues (Zwicky et al., 1961-1968) and from other sources.

The arrangement of galaxies in the merged catalogue is similar to that in morphological catalogue of galaxies. The galaxies are ordered according the increase of right ascension within each of the Palomar sky atlas prints. These prints, in their turn, are arranged in accordance with increasing Right Acension within each zone having the same declination.

Data from UGC catalogue have been added to data already stored in MCG. Data for galaxies with no MCG numbers in UGC were introduced into the corresponding fields arranged by increasing right ascension.

The whole information about each galaxy consists of two parts: the main part, containing exclusively the MCG data, and the additional one, containing the data from notes given for some galaxies in MCG catalogue as well as from the other sources.

The first part includes: MCG and NGC or IC identification numbers, equatorial coordinates for the epoch of 1950.0, diameters and surface brightnesses for the internal and external areas of the galaxy, inclination and detailed morphological description of the galaxy by symbols.

The second part consists of: morphological types of the galaxy by the hubble, de Vaucouleurs, Morgan and van den Bergh's classifications, integrated colour indices, radial velocities, diameters on blue and red PA prints from UGC, position angle, its belonging to near-by clusters from cgcg catalogue, the occurrence in some lists of galaxies, radio flux densities for several wave lengths, the membership in binary or multiple systems, the interaction features, numbers of companions as well as some other parameters.

In compiling the catalogue of galaxies on the magnetic tape we aimed to retain the accepted astronomical symbols as far as possible. To facilitate the work with the computer we have had to encode certain data.

The complete morphological description of each galaxy by means of symbols according to MCG was divided into three parts to simplify the computer comparison of different descriptions of galaxies: the description of 1) general appearance of a galaxy (if the object is described in MCG by means of basic symbols); 2) the bright internal part of a galaxy; 3) the external part of a galaxy.

The description of the external part of a galaxy was carried out from the centre outwards for five similar areas with the similar structure, completely filled by symbols only when there were seen many details in the appearance of a galaxy.in the case of lack of data in the either part, the corresponding places were filled by blanks. The descriptions of galaxies are given with minimized simplification.

Magnetic tape version of the merged catalogue consists of four files. The first file contains the detailed description of the catalogue, the second one - the data concerning the galaxies, the third-bibliographical references and the fourth-detailed description of the information, encoded in the catalogue mentioned.

One of the main purposes of the merged catalogue was to record on the magnetic tape as complete information for each galaxy as possible.at the same time it turned out quite impossible to enter into the first and forth descriptive files all the symbols from MCG catalogue, because of the restricted symbolics of the computer used.

Therefore there had been worked out some main principles for storing of the whole descriptive information on the magnetic tape and particularly for recording of some of the nontrivial symbols from MCG.

1. For designation of some astronomical values there had been utilized conventional in astronomy greek symbols, which were denoted in accordance with abbreviations, accepted in Strasbourg. e.g., alf and del were used for right ascension and declination etc.
2. The small letters, widely adopted in MCG catalogue for the description of some structural features, are represented by capital letters and a point. e. g., a., b. etc.
3. The interliner indices are represented by means of symbols followed by figures. e.g., the angular diameters of the galaxy bright inner part are designated as d.1xd.2 etc.

There should be taken into account the expressions for some of the nontrivial symbols, used by Vorontsov-Velyaminov in MCG, e.g., for description of the spiral arms of galaxies, as seen projected in the sky, Vorontsov-Velyaminov had used two symbols s and reverse s (sometimes referred to as a cyrillic g) to define the two different directions of rotation of a galaxy. Vorontsov- Velyaminov introduces also the term branched spiral arm , represented as ss.s. and reverse ss.s. the existance of spiral arms of both directions in the same galaxy are denoted in MCG by symbols gam or s+reverse s . arrows, which were used by Vorontsov-Velyaminov for designation of the structure transitions are denoted in our case by two computer symbols -> , structure uncertainties of galaxies in MCG-by three symbols (') , the description of the structure incompleteness-by (-) , the uncertainty of morphological type of a galaxy, denoted in catalogues by square brackets, -by symbols (//) etc.

The second file consists of 31917 records for 31917 galaxies. The record length is 364 bytes. The internal computer code is ebcdic.

The author is greatly thankful to the staff of the astronomical data centre of the astronomical council of the academy of sciences of the ussr, and particularly to the department head O. B. Dluzhnevskaya, as well as to A. Piskunov and V. Semyonova, who have accomplished all the work related to the recording of the merged catalogue of galaxies from the formerly used M-220 computer codes to the ES ones.

References

The present catalogue is based on the following works:
1. N.G.Kogoshvili, bul. Abastum. astr. obs., 46, 1975, 133. Catalogue of galaxies brighter than 15-th magnitude on the computer M-220 magnetic tape.
2. N.G.Kogoshvili, coll.n 64 mas, Strasbourg, D. Reidel publ. comp., 1981, 273. The compiled catalogue of galaxies in machine-readable form and its statistical investigation.

columns designation units of measure     ------   notes -------

  1- 11 MCG                           MCG identification number
      1                               zone sign
  2-  3                               zone number
  5-  6                               field number
  8- 10                               galaxy number in the field
     11                               component symbolic designation
 13- 18 NGC/IC                        NGC or IC identification number
     13                               if NGC,  then  n
				      if IC,  then  i
				      a - designation for an anonymous galaxy
				      in rcbg catalogue, otherwise blank
 14- 17                               galaxy number
     18                               component symbolic designation
     20                               if * ,  then additional information is
				      given, otherwise blank
 22- 29 alf(1950)                     right ascension at epoch 1950.0
 22- 23 h.                            hours
 25- 26 m.                            minutes
 28- 29 s.                            seconds
 31- 36 del(1950)                     declination at epoch 1950.0
     31                               sign
 32- 33 degr                          degrees
 35- 36 min                           arc minutes
 38- 42 magn                          integral magnitude
     44                               accuracy of magnitude: coded as 1,  if
				      magnitude was reported in source catalog
				      with accuracy to 0.01 magn
				      as 2,  if to 0.1 magn
				      as 3,  if to 1 magn
 46- 47                               reference for magnitude
     49                               symbol z is used,  if a magnitude is given
				      for two or more galaxies, otherwise blank
     50                               quantity of galaxies having common
				      magnitude
 52- 56 d.1(MCG)    arc min           angular diameters (major and minor axes)
 58- 62 d.2(MCG)    arc min           of the galaxy bright inner part in MCG
     64 id.                           surface brightness of galaxy inner part
				      in the scale of MCG (ref.1)
 66- 70 d1(MCG)     arc min           angular diameters (major and minor axes)
 72- 76 d2(MCG)     arc min           of the whole galaxy in MCG
     78                               >,  if d1, d2 are the lower limits of
				      diameters (for uncertain dimensions),
				      otherwise blank
 80- 81 id                            surface brightness of the galaxy outward
				      regions in the scale of MCG (ref.1)
     83 i.                            The inclination to the line of sight in
				      The scale of MCG (ref.1)
 85- 89 d.1(UGC)    arc min           maximum diameters (major and minor axes)
 91- 95 d.2(UGC)    arc min           measured on the blue Palomar sky survey
	blue PA prints                prints from UGC (ref.10)
 97-101 d.1(UGC)    arc min           maximum diameters (major and minor axes)
103-107 d.2(UGC)    arc min           measured on the red Palomar sky survey
	red PA prints                 prints from UGC (ref.10)
    109                               parameter, estimating the uncertainty in
				      diameters:
				      0  for certain values
				      1  for uncertain values on the blue pa
				      prints only
				      2  for uncertain values on the red pa
				      prints only
				      3  for uncertain values on the blue
				      and red pa prints
111-113 p.                            position angle from UGC (ref.10)
    115                               parameter, estimating the uncertainty
				      in position angle:
				      0  for certain values
				      1  for uncertain values (denoted in UGC
				      by a colon)
				      2  for face-on spirals (values in
				      brackets in UGC)
				      3  for asymmetric systems (values in
				      square brackets in UGC)
117-121                               symbolic description of the general
				      app.earance of a galaxy according to MCG
				      (ref.1). See remark 1 (file 4)
123-126                               symbolic description of the galaxy
				      inner part according to MCG (ref.1).
				      see remark 2 (file 4)
128-166                               symbolic description of the galaxy
				      outward part in MCG (ref.1) divided
				      into five areas:
128-134                               first area
136-142                               second area
144-150                               third area
152-158                               fourth area
160-166                               fifth area
				      see remark 3 (file 4)
    168                               source of classification:(cc170-176)
				      if  U,  then ref.10
				      if  R,  then ref.21
170-176                               galaxy morphological type by de
				      Vaucouleurs classification
				      see remark 4
178-183                               galaxy type by Morgan classification
				      (ref.21). See remark 5
185-192                               galaxy type by hubble classification
				      according to UGC (ref.10) or by van
				      den Bergh classification according
				      to RCBG (ref.21).see remark 6
    194                               source of classification:(cc185-192)
				      if  U,  then ref.10
				      if  R,  then ref.21
196-201 v           km/sec/mpc        radial velocity referred to the sun
    196                               sign of the velocity.
203-204                               reference for v
206-211 v0          km/sec/mpc        radial velocity corrected for solar
				      motion
    206                               sign of the velocity
213-214                               reference for v0
216-218 v.          km/sec/kpc        rotational velocity
220-224 r.h                           distance from the centre to the bend
				      point on rotation curve
				      r.h  in arc min,  if ref.11
				      r.h  in kpc,  if ref.12
    226                               >,  if, r.h is the lower limit
				      otherwise blank
228-229                               reference for v.
231-232 SN 1                          date of an explosion of the first
				      supernova (two last figures of the year)
234-235 SN 2                          date of an explosion of the second
				      supernova (two last figures of the year)
    237                               number of supernovae observed in
239-241                               number of HII regions
243-244                               reference for HII regions
246-250 U-B         magn              integrated U-B colour
252-253                               reference for U-B
255-258 B-V         magn              integrated B-V colour
260-261                               reference for B-V
263-267 (U-B)(0)    magn              integrated 'face-on' (U-B)(0) colour
				      from rcbg (ref.21)
269-272 (B-V)(0)    magn              integrated 'face-on' (B-V)(0) colour
				      from rcbg (ref.21)
274-275                               integral spectrum
277-280 S178        dex(-26)wt/Hz*m*m radio flux density at 178 MHz
282-283                               reference for S178
285-288 S780        dex(-26)wt/Hz*m*m radio flux density at 780 MHz
290-291                               reference for S780
293-296 S1400       dex(-26)wt/Hz*m*m radio flux density at 1400 MHz
298-299                               reference for S1400
301-304 S2700       dex(-26)wt/Hz*m*m radio flux density at 2700 MHz
306-307                               reference for S2700
309-312 S5000       dex(-26)wt/Hz*m*m radio flux density at 5000 MHz
314-315                               reference for S5000
317-319                               number of near-by cluster according
				      to cgcg (ref.2) and taken from UGC
				      (ref.10),  if a galaxy is within the
				      outline of this cluster
    321                               if  1  ,  then the galaxy is contained
				      in ccg catalogue (ref.55)
				      otherwise blank
    323                               if  1  ,  then the galaxy is contained
				      in Markaryan's lists (ref.56)
				      otherwise blank
    325                               if  1  ,  then the galaxy is contained
				      in the catalogue of isolated galaxies
				      by Karachentseva (ref.58)
				      otherwise blank

Remarks

 1 description of the general app.earance of a galaxy according to MCG
   (ref.1)
   field structure: a b c d e
 a description of the general app.earance of a galaxy by means of symbols:
   e, p, l, f
 b description of various structure details coded as follows:
   MCG  tape!MCG  tape!MCG  tape!MCG  tape!MCG  tape!MCG  tape!MCG  tape!
   a.   a   !i.   i   !o.   2   !f.   f   !n.   8   !t.   t   !b.   b   !
   a.d. 5   !e.   e   !m.   m   !z.   z   !c.   c   !a.i. 6   !a    1   !
   w.   w   !l.   9   !d.   d   !b.i. 7   !p.   p   !?    4   !
 c the same as b
 d type of the faint galaxy seen in contact with the main one, or *,  if a
   star is projected on the image of a galaxy
 e structure of the faint galaxy or its inclination to the line of sight.
   in the case of * in  d  there are used codes: 1 - for a star, projected
   on the nuclear region of a galaxy,  2 - on the outer region,  3 - a star
   is close-by to a galaxy,  4 - a star is possibly projected on the galaxy
   image

 2 description of the galaxy inner bright region according to MCG (ref.1)
   field structure: a b c d
 a number of galaxy nuclei seen in contact
 b description of the galaxy inner region by symbols: n, l, n..
   in the case of 'n.' the symbol $ is used on the tape
 c, d structure of a nuclear region, for ()  is used the code  3

 3 description of the galaxy external region according to MCG (ref.1)
   description of the external part of a galaxy was carried out from
   The central regions outwards for five similar areas.for lack of
   information the corresponding areas were filled with blanks.
   field structure for one of the abovementioned similar 5 areas:
   a b c d e f g
 a area separating symbols according to MCG,  coded as follows:
    MCG  tape!MCG  tape!MCG  tape!MCG  tape!
    ,     ,    !;    ;   !;;   1   !->   2   !
 b number of structure details described in  c  .in the case of b=9,
   b  must be considered as duplication of symbols in  c
 c   description of galaxy external areas by symbols,  coded as follows:
    MCG  tape!MCG  tape!MCG  tape!MCG  tape!MCG  tape!MCG  tape!MCG  tape!
    s    s   !h    h   !b    b   !t    t   !cam  6   !r    r   !l.   9   !
    c    c   !ss.s.4   !d    d   !l    l   !r.   @   !s.   2   !
    MCG            tape!MCG            tape!MCG            tape!
    'reverse ss.s.'3   !'reverse s.'+s.0   !'reverse s'    #   !
    'reverse s.'   1   !'reverse s'+s  5   !'arcs'         8   !
 d, e, f description of various structure details (the same as  b  in
   remark 1),  as well as the following codes: k - for a galaxy with sharp
   edges,  x - for the traces of structure,  q - for the uncertainty in
   The number of arms
 g uncertainties in structure details coded as follows:
    MCG  tape!MCG  tape!MCG  tape!MCG  tape!MCG  tape!MCG  tape!MCG  tape!
    '    1   !(')  4   !->r  r   !-    2   !->8  8   !()   3   !(-)  6   !

 4 morphological type of a galaxy by de Vaucouleurs classification
   according to rcbg (ref.21), or UGC (ref.10)
   field structure: a b c d e f g
 a existance of outward ring
 b,  c, d, e galaxy type
 f, g peculiarities

 5 type of a galaxy by Morgan's classification according to rcbg (ref.21)
   field structure: a b c d e f
 a, b,  c galaxy type
 d, e spectral class
 f peculiarities

 6 type of a galaxy by Hubble's classification according to UGC (ref.10),
   or van den Bergh's classification according to RCBG (ref.21)
   field structure: a b c d e f g h
   for the case of hubble's classification (ref.10), we have:
 a, b, e, f galaxy type coded as follows:
    UGC       tape!UGC       tape!UGC       tape!UGC       tape!
    e         e   !e0        e0  !s         s   !so        so  !
    sb        sb  !sbo       s1  !p         p   !ir.r.     i   !
   dwarf      1   !dwarf s   2   !dwarf i   3   !dwarf e   4   !
    dwarf p   5   !
 c, g structure details coded as follows:
    UGC  tape!UGC  tape!UGC  tape!UGC  tape!UGC  tape!
    a.   a   !b.   b   !a.-b.1   !c.   c   !b.-c.2   !
 d additional symbols coded as follows:
    UGC  tape!UGC  tape!UGC  tape!UGC  tape!UGC  tape!
    :    :   !?    1   !/    /   !(//) 2   !-    3
 h luminosity class
   for the case of van den Bergh's classification (ref.21), we have:
 a, b galaxy type
 c structure details
 d peculiarities,  additional symbols
 e, f, g characteristics of spiral arms
 h luminosity class
 7 app.earance of a galaxy in binary or multiple system
   field structure: a b c d
 a the following codes are used:
    1 the galaxy has a companion with MCG identification number
    2 the galaxy has a companion with no MCG identification number
    3 for more than one galaxy in a system described by one MCG
      identification number
 b designation of members in binary and multiple systems
    1 for the brightest member in a multiple system
    k for one of the fainter members in a multiple system
    2 for one of the members of binary system
    d for another member of binary system
    3 for the brightest member of triple system
    t for one of the fainter members of triple system
 c if  a=1,  then  c=xxx (MCG number of the component in the field,
   positions 8-10), otherwise blank
 d degree of isolation of galaxy pairs according to Karachentsev
   (ref.57),  coded as follows:
    ref.57  tape!  ref.57  tape!  ref.57  tape!  ref.57  tape!
    +, +     1   !  -, -     2   !  +, -     3   !  -, +     4

 8 existance of the interaction features
   field structure: a b c d e
 a number of the members observed in interaction
 b the following codes are used:
    if  b  then interaction is evident
    if  q  then interaction is suspected, otherwise blank
 c type of interaction,  coded as follows:
    if  1  then galaxies are connected with a bar
    if  2  then a galaxy is connected with another one by a spiral arm
    if  3  then contact of galaxies
    if  4  then contact of galaxy nuclei
    if  5  then a nest of galaxies
    if  6  then a chain of galaxies
    if  7  then galaxies are embedded in common nebulous envelope
 d description of app.arent galaxy form distortion by means of codes:
    if  1  then existance of a tail
    if  2  then existance of unusual branched features (jet, streamer,
	   plume, etc.)
    if  3  then a halo
    if  4  then clear evidence of structure distortion
    if  7  then galaxies are embedded in common nebulous envelope
 e angular separation of members in system in minutes of arc (e=x.x)

 9 existance of faint components
   field structure: a b c d
 a number of faint components
 b the following codes are used:
    1 a galaxy has a faint component with MCG identification number
    2 a galaxy has a faint component with no MCG identification number
    3 a galaxy has a faint galaxy close-by
    4 a galaxy has a questionable object (star or defect),  close-by
 c either MCG number of a component in the field (if b=1), or a magnitude
   of a nearest component (if b=2, 3, 4).c=xx
 d angular distance to the nearest companion in minutes of arc.d=x.x

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