GCVSEGVARS - General Catalog of Variable Stars (GCVS4.2): Extragalactic Variables
The present improved electronic version of the GCVS 4th Edition, Volumes I-V, combined with the Name-Lists of Variable Stars Nos. 67 - 77, is also available from the Sternberg Institute via anonymous ftp to ftp://ftp.sai.msu.su/pub/groups/cluster/gcvs/gcvs/ and more information is available via the Web at http://www.sai.msu.su/groups/cluster/gcvs/gcvs/.
General Catalogue of Variable Stars, 4th ed., vol. V. Extragalactic Variable Stars Artiukhina N.M., Durlevich O.V., Frolov M.S., Goranskij V.P., Gorynya N.A., Karitskaya E.A., Kazarovets E.V., Kholopov P.N., Kireeva N.N., Kurochkin N.E., Lipunova N.A., Medvedeva G.I., Pastukhova E.N., Samus N.N., Tsvetkova T.M. <"Kosmosinform", Moscow, (1995)>
This is a numeric code for the galaxy name, ranging from 89 for the LMC to 123 for the WLM Galaxy (codes 1-88 in the GCVS are reserved for constellation names for galactic variable stars). The galaxy codes are as follows:
Gal. Code Galaxy Gal. Code Galaxy Gal. Code Galaxy 89 LMC 90 SMC 91 M 31 92 M 33 93 NGC 147 94 NGC 185 95 NGC 205 96 NGC 300 97 Scl Galaxy 98 IC 1613 99 ESO 356- 4 100 NGC 1313 101 NGC 1466 102 Ret Galaxy 103 PGC 19441 104 NGC 2366 105 NGC 2403 106 Holmberg II 107 NGC 3031 108 Sextans B 109 Leo A 110 NGC 3109 111 Leo I 112 Sextans A 113 NGC 4365 114 NGC 4472 115 NGC 4486 116 NGC 5128 117 NGC 5457 118 UGC 9749 119 UGC 10822 120 NGC 6822 121 IC 5152 122 UGC 12613 123 WLM Galaxy
The Variable Star Number within the specified galaxy.
The GCVS Extragalactic Variable Star designation.
This flag is set to 'Y' if there is a remark on this star in the file: http://cdsarc.u-strasbg.fr/ftp/cats/II/250/evs_rem.dat.
The Right Ascension of the star in the specified equinox. This was given to no better than a precision of 0.1 seconds of time in the originating table, and in 1950 equatorial co-ordinates.
The Declination of the star in the specified equinox. This was given to a precision of 1 arcsecond in the originating table, and in 1950 equatorial co-ordinates.
The Galactic Longitude of the star.
The Galactic Latitude of the star.
This is a code flag describing the positional accuracy, as follows:
'A' means right ascensions accurate to one second of time and declinations accurate to one arcsecond; 'B' means declinations accurate to 0.1 arcminutes; 'C' means declinations accurate to one arcminute; 'D' means for V474 in the Sculptor system (V474 SclG), the listed coordinates refer to the galaxy's center since the coordinates of the star itself are unknown.
The type of variability according to the GCVS variability classification scheme, with the addition of the new "BLBOO" type, named after the prototype star BL Boo = NGC 5466 V19 referring to the so-called "anomalous Cepheids", i.e. stars with periods characteristic of comparatively long-period RRAB variables, but considerably brighter in luminosity. There are also suspected variables designated by the symbol "var:".
The apparent magnitude at maximum brightness.
This flag is set to ':' if the maximum magnitude is considered uncertain.
This is a limit flag for the minimum magnitude: '>' indicates that the min_mag value given is a bright limit, i.e., the actual minimum magnitude is fainter than this value, while '(' means that the min_mag value given is an amplitude rather than an observed magnitude.
This parameter is either the apparent magnitude at minimum brightness, or, if the value of limit_min_mag is '(', the amplitude of variation.
This flag is set to ':' if the min_mag value is considered uncertain.
The designation of the photometric band in which the magnitudes are given: P means photographic magnitudes, V means visual or photovisual magnitudes as well as Johnson V system magnitudes. In the latter case, they are usually distinguishable from visual magnitudes by the number of digits after the decimal point (as a rule, V system magnitudes are based upon photoelectric or CCD photometry). The letters U, B, R, I, J, H, K, L, M, N, O, Q mean, as a rule, magnitudes expressed in the corresponding systems of broad-band photometry.
The epoch of maximum or minimum, expressed as the Julian Date. For eclipsing and ellipsoidal variables, RV Tau and RS CVn stars, the catalog gives the epoch of minimum light, while for the rest of variables, it gives the epoch of maximum light. For novae (variability_type N) and supernovae (variability_type SN), the epoch is completed by the year of the outburst (nova_year parameter).
This flag is set to ':' if the epoch is considered uncertain.
A code qualifying the period, that is set to '(' if the period is the mean cycle time of a U Gem star or recurrent nova.
The period of the variable star, in days, or, if limit_period = '(', the mean cycle time of a U Gem star or recurrent nova. This parameter is given with a range of precisions up to a possible maximum of 1.E-08 days in the original table.
This flag is set to ':' if the period is considered uncertain.
This parameter contains either the rise time (M-m, the duration of light increase from minimum to maximum) for intrinsic variables, or the duration of the eclipse (D) for eclipsing or Algol-type binaries. The value is given as a percentage of the period of the star.
This flag is set to ':' if the rise time or eclipse duration given in the rise_eclipse_time parameter is considered uncertain.
This is a note used for eclipsing variables that is set to '0' when the duration of the light constancy phase at minimum light (d) is equal to zero.
The spectral type of the variable star. If there exist several spectral type determinations for a star, the more recent ones have been preferred, taking into account the reliability of each determination. The symbols "d" (dwarfs) and "g" (giants) have been converted into luminosity classes V and III, respectively. If a star showed spectral features typical of novae during or after the outburst, a symbol 'NOVA' is given in this parameter. If the spectrum showed features characteristic of U Gem variables, this parameter contains the symbol 'UG'. A continuous spectrum is designated as 'cont', the symbol 'e' means an emission-line spectrum, lower-case letters 'ea', 'eb' in this field stand for 'e alpha', 'e beta'. For RR Lyrae stars, spectral types derived from hydrogen lines are given. A plus sign (+) between two spectral type values means that the spectra of two components of a spectroscopic binary are observed. Two spectral type values separated with a minus sign (-) give the range of spectral type variations in the process of brightness changes.
This is a reference code referring to a major study of the star, the key to which can be found in the file: http://cdsarc.u-strasbg.fr/ftp/cats/II/250/refs.dat.
This is a reference code referring to a study that contains a chart or photograph of the star field, the key to which can be found in the file: http://cdsarc.u-strasbg.fr/ftp/cats/II/250/refs.dat.
An alternative designation for the variable star that is used in the reference whose code is given in the ref_star parameter.
An alternative designation for the variable star that is used in the reference whose code is given in the ref_chart parameter.
The alternative GCVS or NSV designation for the variable star.
This is a flag indicating the non-membership status of the variable star in the Galaxy in whose field the star lies. The symbols 'N' or 'N:' indicate non-membership and possible non-membership, respectively, in the galaxy in question. For the stars that are in the main GCVS (vols. I-III) or the GCVS Catalog of Newly Suspected Variables (NSV) and which are not members of the corresponding galaxy, the present catalog typically gives only the Extragalactic Variable running number, the coordinates, the symbol 'N' in this field, and the GCVS or NSV name.
The year of outburst of the star, if a nova.
This flag is set to ':' if the outburst year of the nova is considered uncertain.
The HEASARC Browse object classification, based on the spectral type parameter (spect_type), if there is information in this field, else based on the variability type parameter (variability_type).