| name | type | length | unit | ucd | description |
| name | varchar | 20 | | ID_AREA | Primary name |
| aliases | varchar | 20 | | | Other names |
| PGC_name | varchar | 10 | | | PGC (Paturel et al. 1989a,b) designation |
| ra | float | 8 | degrees | POS_EQ_RA | Right Ascension (J2000) |
| dec | float | 8 | degrees | POS_EQ_DEC | Declination (J2000) |
| good_position | int | 4 | | | The values of ra/dec are good to 0.1 sec time, 1 asec (otherwise, 0.1 min time, 1 amin) |
| galactic_l | float | 8 | degrees | POS_EQ_RA | Galactic longitude in the IAU 1958 system (Blaauw et al. 1960); good to 0.01 degrees |
| galactic_b | float | 8 | degrees | POS_EQ_DEC | Galactic latitude in the IAU 1958 system (Blaauw et al. 1960); good to 0.01 degrees |
| superGalactic_l | float | 8 | degrees | POS_EQ_RA | Supergalactic longitude in the RC2 system; good to 0.01 degrees |
| superGalactic_b | float | 8 | degrees | POS_EQ_DEC | Supergalactic latitude in the RC2 system; good to 0.01 degrees |
| PosAngle | float | 8 | degrees | | position angle, measured in degrees from north through east (all p.a. < 180 degrees), taken when available from UGC, ESO, and ESGC (and in a few cases from HI data). |
| rc2_type | char | 7 | | | mean revised morphological type in the RC2 system, coded as in RC2 |
| rc2_typeSource | char | 6 | | | Sources of revised morphological type estimate |
| T_type | float | 8 | | | Mean numerical index of stage along the Hubble sequence in the RC2 system |
| T_typeErr | float | 8 | | | Error in T_type |
| LC_rc2 | float | 8 | | | Mean numerical luminosity class in the RC2 system |
| LC_rc2Err | float | 8 | | | Error in LC_rc2 |
| n_L | float | 8 | | | Number of luminosity class estimates |
| B_T | float | 8 | magnitudes | | Total (asymptotic) magnitude in the B system, derived by extrapolation from photoelectric aperture-magnitude data, B_T^A, and from surface photometry with photoelectric zero point, B_T^S |
| B_TErr | float | 8 | magnitudes | | Error in B_T |
| B_Tsource | char | 1 | | | M when B_T is the weighted mean of B_T^A and B_T^S; V when B_T is a V-band magnitude rather than a B-band magnitude; v when the nucleus of the galaxy is variable; * when deriving B_T^A would have required an extrapolation in excess of 0.75 mag. |
| B_T0 | float | 8 | magnitudes | | total ``face-on'' magnitude corrected for Galactic and internal extinction, and for redshift |
| M_B | float | 8 | magnitudes | | Photographic magnitude from Ames (1930), Shapley and Ames (1932), CGCG, Buta and Corwin (1986), and/or Lauberts and Valentijn (1989) reduced to the B_T system |
| M_BErr | float | 8 | magnitudes | | Error in M_B |
| M_FIR | float | 8 | magnitudes | | Far-infrared magnitude calculated from M_FIR = - 20.0 - 2.5 log_10(FIR), where FIR is the far infrared continuum flux measured at 60 and 100 microns as listed in the IRAS Point Source Catalog (1987). For galaxies larger than 8 arcmin in RC2 and for the Virgo cluster area, resolved by the IRAS beam, integrated fluxes are taken from Rice et al. (1988) or Helou et al. (1988) |
| M_21cm | float | 8 | magnitudes | | 21-cm emission line magnitude, and its mean error, defined by m_21 = 21.6 - 2.5 log(S_H), where S_H is the measured neutral hydrogen flux density in units of 10^-24 W/m^2 |
| M_21cmErr | float | 8 | magnitudes | | Error in M_21cm |
| BV_T | float | 8 | magnitudes | | Total (asymptotic) color index in the Johnson B-V system, derived by extrapolation from photoelectric color-aperture data, and/or from surface photometry with photoelectric zero point |
| BV_TErr | float | 8 | magnitudes | | Error in BV_T |
| BV_T0 | float | 8 | magnitudes | | Total B-V color index corrected for Galactic and internal extinction, and for redshift |
| BV_e | float | 8 | magnitudes | | Mean B-V color index within the effective aperture A_e, derived by interpolation from photoelectric color-aperture data |
| BV_eErr | float | 8 | magnitudes | | Error in BV_e |
| UB_T | float | 8 | magnitudes | | Total (asymptotic) color index in the Johnson U-B system, derived by extrapolation from photoelectric color-aperture data, and/or from surface photometry with photoelectric zero point |
| UB_TErr | float | 8 | magnitudes | | Error in UB_T |
| UB_T0 | float | 8 | magnitudes | | Total U-B color index corrected for Galactic and internal extinction, and for redshift |
| UB_e | float | 8 | magnitudes | | Mean U-B color index, and its mean error, within the effective aperture A_e, derived by interpolation from photoelectric color-aperture data |
| UB_eErr | float | 8 | magnitudes | | Error in UB_e |
| lgD_25 | float | 8 | lg(0.1 arcmin) | | mean decimal logarithm of the apparent major isophotal diameter measured at or reduced to surface brightness level mu_B = 25.0 B-mag/arcsec^2 |
| lgD_25Err | float | 8 | 0.1 arcmin | | Error in lgD_25 |
| lgD_0 | float | 8 | lg(0.1 arcmin)? | | decimal logarithm of the isophotal major diameter corrected to ``face-on'' (inclination = 0 degrees), and corrected for Galactic extinction to A_g = 0, but not for redshift |
| lgR_25 | float | 8 | | | Mean decimal logarithm of the ratio of the major isophotal diameter, D_25, to the minor isophotal diameter, d_25, measured at or reduced to the surface brightness level mu_B = 25.0 B-mag/arcsec^2 |
| lgR_25Err | float | 8 | | | Error in lgR_25 |
| logA_e | float | 8 | | | Decimal logarithm of the apparent diameter (in 0.1 arcmin) of the ``effective aperture,'' the circle centered on the nucleus within which one-half of the total B-band flux is emitted |
| logA_eErr | float | 8 | | | Error in logA_e |
| m_e | float | 8 | magnitudes | | mean B-band surface brightness in magnitudes per square arcmin (B-mag/arcmin^2) within the effective aperture A_e, as given by the relation m'_e = B_T + 0.75 + 5logA_e - 5.26. m'_e is statistically related to the effective mean surface brightness, mu'_e (RC2, p. 31; Olson and de Vaucouleurs 1981), with which it coincides when log R = 0 (i = 0 degrees) |
| m_eErr | float | 8 | magnitudes | | Error in m_e |
| m_25 | float | 8 | magnitudes/arcmin^2 | | m'_25 = the mean surface brightness in B-mag/arcmin^2 within the mu_B = 25.0 B-mag/arcsec^2 elliptical isophote of major axis D_25 and axis ratio R_25, defined as in RC2 (Equation 21) by: m'_25 = B_T + Delta m_25 + 5 logD_25 - 2.5 logR_25 - - 5.26, where Delta m_25 = 2.5 log(L_T/L_D_25) = B_25 - B_T is the magnitude increment contributed by the outer regions of a galaxy fainter than mu_B = 25.0 B-mag/arcsec^2 |
| m_25Err | float | 8 | magnitudes/arcmin^2 | | Error in m_25 |
| A_B | float | 8 | magnitudes | | Galactic extinction in B-band magnitudes, calculated following Burstein and Heiles (1978a,b, 1982, 1984) |
| A_HI_self | float | 8 | magnitudes | | HI line self-absorption in magnitudes (for correction to face-on), calculated from logR and T >= 1 |
| A_B_int | float | 8 | magnitudes | | internal extinction in B-band magnitudes (for correction to face-on), calculated from logR and T |
| W_20 | float | 8 | km/s | | Neutral hydrogen line full width measured at the 20% level (I_20/I_max) |
| W_20Err | float | 8 | km/s | | Error in W_20 |
| W_50 | float | 8 | km/s | | Neutral hydrogen line full width measured at the 50% level (I_50/I_max) |
| W_50Err | float | 8 | km/s | | Error in W_50 |
| HI | float | 8 | magnitudes | | corrected neutral hydrogen index, which is the difference m_21^0 - B_T^0 between the corrected (face-on) 21-cm emission line magnitude and the similarly corrected magnitude in the B_T system. N.n. Since m_21 and B_T are provided in this table, there is no need to list the uncorrected index. |
| V_21cm | float | 8 | km/s | | Mean heliocentric radial velocity, and its mean error, in km/s derived from neutral hydrogen observations |
| V_21cmErr | float | 8 | km/s | | Error in V_21cm |
| V_opt | float | 8 | km/s | | mean heliocentric radial velocity, and its mean error, in km/s derived from optical observations |
| V_optErr | float | 8 | km/s | | Error in V_opt |
| V_GSR | float | 8 | km/s | | weighted mean of the neutral hydrogen and optical velocities, corrected to the ``Galactic standard of rest |
| V_3K | float | 8 | km/s | | weighted mean velocity corrected to the reference frame defined by the 3 K microwave background radiation |
| htmID | bigint | 8 | | CODE_HTM | 20-deep hierarchical trangular mesh ID of this object |
| cx | float | 8 | | POS_EQ_CART_X | unit vector for ra+dec |
| cy | float | 8 | | POS_EQ_CART_Y | unit vector for ra+dec |
| cz | float | 8 | | POS_EQ_CART_Z | unit vector for ra+dec |
| objId | bigint | 8 | | ID_MAIN | the main primary key |