GCVS - General Catalog of Variable Stars, March 2012 Version
The total number of designated variable stars has now reached 45835. Errors detected in the printed Volumes I-III and in the Name-Lists have been corrected.
There are 157 stars for which no positions are listed as they are now considered to be duplicates of other stars in the GCVS.
The present improved electronic version of the GCVS 4th Edition, Volumes I-V, combined with the Name-Lists of Variable Stars Nos. 67 - 79, is also available from the Sternberg Institute of Moscow University via at ftp://ftp.sai.msu.su/pub/groups/cluster/gcvs/gcvs/ or http://www.sai.msu.su/gcvs/gcvs/.
General Catalog of Variable Stars (GCVS database, Version 2012Apr) Samus N.N., Durlevich O.V., et al. <Institute of Astronomy of Russian Academy of Sciences and Sternberg State Astronomical Institute of the Moscow State University >
The GCVS numeric designation of the variable star, made from the constellation and star names codes. The numeric code for the constellation name is in alphabetic order of the full constellation name, so, for example, Cancer or CNC has a code value of 12 which precedes the code value of 16 for Capricornus or CAP). The codes are as follows:
Constellation Constell_code Constellation Constell_code Name Name And 1 Ant 2 Aps 3 Aqr 4 Aql 5 Ara 6 Ari 7 Aur 8 Boo 9 Cae 10 Cam 11 Cnc 12 CVn 13 CMa 14 CMi 15 Cap 16 Car 17 Cas 18 Cen 19 Cep 20 Cet 21 Cha 22 Cir 23 Col 24 Com 25 CrA 26 CrB 27 Crv 28 Crt 29 Cru 30 Cyg 31 Del 32 Dor 33 Dra 34 Equ 35 Eri 36 For 37 Gem 38 Gru 39 Her 40 Hor 41 Hya 42 Hyi 43 Ind 44 Lac 45 Leo 46 LMi 47 Lep 48 Lib 49 Lup 50 Lyn 51 Lyr 52 Men 53 Mic 54 Mon 55 Mus 56 Nor 57 Oct 58 Oph 59 Ori 60 Pav 61 Peg 62 Per 63 Phe 64 Pic 65 Psc 66 PsA 67 Pup 68 Pyx 69 Ret 70 Sge 71 Sgr 72 Sco 73 Scl 74 Sct 75 Ser 76 Sex 77 Tau 78 Tel 79 Tri 80 TrA 81 Tuc 82 UMa 83 UMi 84 Vel 85 Vir 86 Vol 87 Vul 88The star number within the constellation, which typically corresponds to the order in which the variables were found. For historical reasons, the first designated variable star in a constellation was given the name 'R constellation', e.g., 'R CMa', the second the prefix 'S', etc, the ninth 'Z', the tenth 'RR', etc., the 55th 'AA', etc, until the 334th 'QZ', at which point the letters have been exhausted, and the 335th variable is given the 'V0335' (or V335) prefix, e.g., 'V0335 And', and so on for all subsequent discoveries in the constellation.
The component identification, 'A', 'B', etc., i.e., the designations of components of double/multiple stars. Usually, only one component of the binary is variable, but there are 2 cases (CE Cas A and B, and EQ Peg A and B) where both components are variable and are listed as separate entries in the catalog.
The variable star designation. For a brief explanation of the variable star naming convention, see the help entry for the variable_star_number parameter. Notice that stars which have Bayer designations, e.g. Alpha Ori, which have been discovered to be variable stars have not been given a new variable star designation but are listed by their Bayer designation in the GCVS, e.g., as 'alf Ori'. (The traditional transliterations of Greek letters are used, e.g., 'alf' for alpha). There are also a small number of historical variable stars which were named using lower-case latin characters, e.g. g Her and u Her. The lower- and upper-case latin letters must be distinguished, notice, because in some cases, e.g., u Her and U Her, there are names for completely different stars using the alternate naming conventions.
This flag is set to 'Y' if there are notes on this star in the published version of the catalog: these comments can be found in ftp://cdsarc.u-strasbg.fr/cats/B/gcvs/gcvs_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.
The Declination of the star in the specified equinox. This was given to a precision of 1 arcsecond in the originating table.
The Galactic Longitude of the star.
The Galactic Latitude of the star.
This is a code flag describing the positional accuracy, as follows:
':' means the position is uncertain 'Y' means that the coordinates could not be improved and that they were recalculated from old coordinates to the J2000.0 equinox with allowance for precession
The type of variability according to the GCVS variability classification scheme. The system of variable star classification corresponds to the GCVS, 4th edition, with six additional classes (ZZO, AM, R, BE, LBV, and BLBOO) that were introduced in the Name-Lists 67 - 72 and in the GCVS vol. V. The full scheme is described in the file: ftp://cdsarc.u-strasbg.fr/cats/B/gcvs/vartype.txt. The HEASARC has made one change to the schema therein described: unique variable stars outside of the range of the GCVS classification scheme are designated as 'Unique', rather than by '*' as in the reference, so as to avoid confusion with the wild-card asterisk character.
This parameter is a limit [<>] or amplitude flag [(] for the maximum magnitude, where '>' indicates that the latter is a faint limit, '<' that it is a bright limit, and '(' that it is an amplitude rather than an observed magnitude.
The apparent magnitude at maximum brightness, or, if the value of limit_max_mag is '(', the amplitude of variation.
This flag is set to ':' if the maximum magnitude is considered uncertain.
This is a limit flag for the minimum magnitude, '>' indicating that the latter is a bright limit., and '(' that it 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 minimum magnitude is considered uncertain.
This is a code which is non-blank when the minimum magnitude or amplitude (min_mag) is given in an alternative photometric system to the one for the maximum magnitude (max_mag) which is given by the mag_system parameter. These codes are described in the parameter help for the mag_system parameter.
The photometric system in which the maximum and minimum (unless min_mag_altsys is non-blank) magnitudes are reported. The main codes used are p (photographic magnitudes) and V (visual, photovisual, or Johnson V). Several stars from the 68th Name-List have values of '1.' designating the 1.04 micrometer band of the system introduced by G.W. Lockwood. The designations u, v, b, and y refer to the Stroemgren system, the symbols 'Ic'and 'Rc' mean magnitudes in Cousins' RI system, 'g' designates magnitudes in the system of Thuan and Gunn, 'T' stands for broad-band Tycho magnitudes formed from B and V measurements, while 'r' indicates red magnitudes that are not tied to a particular system. Observations made in 'white light' are indicated by 'w' (rather than '*' as in the original table).
This is generally the epoch for maximum light, in Julian Days, except for all eclipsing and ellipsoidal variables, as well as for RV Tau and RS CVn types, where it is the epoch for minimum light. This rule may occasionally be broken, but this is explained only in the remarks to the catalog.
The precision of the quoted epoch value, i.e., the number of digits after the decimal point in the original table. Thus, a precision of 4 means that the epoch was given to 10-4 days in the original table.
This parameter is a flag qualifying the epoch according to the following codes:
':' epoch is uncertain; '+' epoch may be later than that reported; '-' epoch may be earlier than that reported.
The year of outburst for a nova or supernova. The exact date of maximum light is given in JD in the epoch parameter.
This parameter is set to ':' to indicate that there is uncertainty in the year of the nova or supernova outburst.
A code qualifying the period, as follows: '>' or '<' if the period is a lower or upper limit, respectively, or '(' if the period is the mean cycle time of a U Gem or recurrent nova.
The period of the variable star, in days. This is given with a range of precisions up to a possible maximum of 1.E-10 days in the original table.
The precision of the quoted period value, i.e., the number of digits after the decimal point in the original table. Thus, a precision of 4 means that the period was given to 10-4 days in the original table.
This is another flag that contains information if the actual period may be either a multiple ('MN' or 'M2') or a fraction ('FN') of the quoted period value.
This parameter contains either the rise time (M-m) for intrinsic variables, or the duration of the eclipse (D) for eclipsing binaries. These values help to define the shape of the light curve. 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, or to ':' if the value is considered uncertain.
The spectral type of the variable star.
This is a reference code referring to a major study of the star, as follows: (the codes and their corresponding references can be found in ftp://cdsarc.u-strasbg.fr/pub/cats/B/gcvs/refs.dat)
"00002" - "09148" - Vol. I GCVS (see Kholopov et al., 1985-1988) "09149" - "09558" - Vol. II GCVS "09559" - "10200" - Vol. III GCVS "67001" - "77229" - Name-Lists Nos.67-77References from Vol. V (extragalactic variables) start with the letter 'V', and references to the suspected variables start with 'N' (first part) or 'S' (supplement). References may also be abbreviations of catalog names (BD, CPD, CoD, GSC, HIP, USNO).
This is a reference code referring to a reference containing a chart or photograph of the star field, as follows: (the codes and their corresponding references can be found in the file ftp://cdsarc.u-strasbg.fr/pub/cats/B/gcvs/refs.dat)
"00002" - "09148" - Vol. I GCVS (see Kholopov et al., 1985-1988) "09149" - "09558" - Vol. II GCVS "09559" - "10200" - Vol. III GCVS "67001" - "77229" - Name-Lists Nos.67-77References from Vol. V (extragalactic variables) start with the letter 'V', and references to the suspected variables start with 'N' (first part) or 'S' (supplement). References may also be abbreviations of catalog names (BD, CPD, CoD, GSC, HIP, USNO), if no chart is available for the variable, but the star is contained in one of the Durchmusterung catalogs, the Hubble Space Telescope Guide Star Catalog (GSC), the Hipparcos (HIP) Catalog, or the USNO Catalog.
This parameter is a miscellaneous flag with the following meanings:
'=' indicates the star is also known under another variable name '+' indicates the star is in other catalogs (e.g. Hipparcos or Name Lists) 'N' indicates the star does not exist
An alternative designation for the variable.
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).