GC+HIP

Description



Field 1:
HIP number
Number of the star in the HIPPARCOS Catalogue (ESA 1997).
This numbering follows closely ordering by right ascension alpha
for the epoch J1991.25 (not J2000.0 !).

Field 2:
FK6 number
The FK6 number of the star (Wielen et al. 1999d, 2000) is identical with its
FK5 number (for the FK5 stars) or its FK4Sup number (for the RSup stars).

Field 3:
Flag for the subsample of FK6 stars
   BA = basic FK5 star
   BX = star from the bright extension of the FK5
   FX = star from the faint extension of the FK5
   RS = star from the RSup (Schwan et al. 1993).

Field 4:
GC number
Number of the star in the GC (Boss et al. 1937).

Fields 5 - 4:
The Fields 5 - 14 contain the GC+HIP results in the single-star (SI) mode.

Field 5:
alpha 2000 (SI mode)
The right ascension alpha of the star at epoch and equinox J2000.0 in
the ICRS/HIPPARCOS system for the SI mode of the GC+HIP. alpha is given in
the printed catalogue in the conventional sexagesimal
units of hours, minutes of time, and seconds of time. The
machine-readable version of the GC+HIP gives alpha also in degrees and
decimal fractions of degrees. Below we use the notation alpha_* =
alpha*cos(delta), as it is done in the HIPPARCOS Catalogue.

Field 6:
delta 2000 (SI mode)
The declination delta of the star at epoch and equinox J2000.0 in the
ICRS/HIPPARCOS system for the SI mode of the GC+HIP. delta is given in the
printed catalogue in the conventional sexagesimal
units of degrees, minutes of arc, and
seconds of arc. The machine-readable version of the GC+HIP gives delta also
in degrees and decimal fractions of degrees.

Field 7:
mu_alpha_* 2000 (SI mode)
The proper-motion component mu_alpha_* of the star in alpha_* at epoch and equinox J2000.0 in
the ICRS/HIPPARCOS system for the SI mode of the GC+HIP. Instead of the
conventional way of presenting mu_alpha, the catalogue gives
mu_alpha_* = mu_alpha*cos(delta) in milliarcseconds (mas)/year.

Field 8:
mu_delta 2000 (SI mode)
The proper-motion component mu_delta of the star in delta at epoch and
equinox J2000.0 in the ICRS/HIPPARCOS
system for the SI mode of the GC+HIP. Units: mas/year.

Field 9:
T_alpha (SI mode)
Central epoch T_alpha in alpha of the star in the SI mode. The catalogue
gives T_alpha - 1900 in order to save printing space. Units: years.

Field 10:
epsilon_alpha_* (SI mode)
Mean error epsilon_alpha_* of alpha_* of the star at the
central epoch T_alpha (given in Field 9) in the SI mode. Units: mas.

Field 11:
epsilon_mu_alpha_* (SI mode)
Mean error epsilon_mu_alpha_* of mu_alpha_* of the star in the SI mode. Units: mas/year.

Field 12:
T_delta (SI mode)
Central epoch T_delta in delta of the star in the SI mode. The catalogue
gives T_delta - 1900 in order to save printing space. Units: years.

Field 13:
epsilon_delta (SI mode)
Mean error epsilon_delta of delta of the star at the
central epoch T_delta (given in Field 12) in the SI mode. Units: mas.

Field 14:
epsilon_mu_delta (SI mode)
Mean error epsilon_mu_delta of mu_delta of the star in the SI mode. Units: mas/year.

Field 15:
p_H
Parallax p_H of the star, given in the HIPPARCOS Catalogue (HIP Field H11). Units: mas.

Field 16:
epsilon_p_H
Mean error epsilon_p_H of p_H. Units: mas.

Field 17:
v_rad 
Radial velocity v_rad of the star, used in calculating the foreshortening effect. Units: km/s.

Field 18:
m_V
Apparent visual magnitude m_V of the star, taken from the HIPPARCOS Catalogue.

Field 19:
K_m
Flag for the variability of the brightness of the star, taken from the HIPPARCOS Catalogue (HIP Field H6):
       blank = star not variable
           1 = star variable at the level of < 0.06 mag
           2 = star variable at the level of 0.06 - 0.6 mag
           3 = star variable at the level of > 0.6 mag

Field 20:
K_bin
Flag for the double-star nature of the object:
K_bin = d_1,d_2 = 10*d_1 + d_2
 First digit d_1:
 The first digit d_1 describes the information on the double-star nature based
 on the proper-motion differences Delta_mu. The method and the meaning of
 the corresponding test parameters F are explained in Wielen et al. (1999a).
 1 = all values of F (F_{FH}, F_{0H}, F_{0(GC)H}, F_{0F}, F_{TH}) are below 2.49
 2 = at least one value of F (F_{FH}, F_{0H}, F_{0(GC)H}, F_{0F}, F_{TH}) is larger than 3.44
 3 = all other (intermediate) cases
 Second digit d_2:
 The second digit d_2 describes the information on the double-star nature based on various other methods. If
 the data indicate various kinds of binarity, the'astrometrically most disturbing' effect is given.
   1 = single star indicated
   2 = the star is a member of a visual binary (gravitationally bound system),
       or the object is  resolved by speckle interferometry
   3 = the object is suspected to be a visual binary (mainly due to HIP)
   4 = the star has at least one optical companion with a separation of rho < 60"
   5 = the star has at least one optical companion, but all companions have a separation of rho >= 60"
   6 = astrometric binary (mainly the non-standard solutions O, G, V, X of HIP)
   7 = spectroscopic binary with a known orbit,  or the star is an eclipsing binary
   8 = the radial velocity of the star is variable (indicating a spectroscopic binary),
       or the object shows a composite spectrum (indicating a double star)
   9 = the radial velocity of the star may be variable (possible indication for a spectroscopic binary),
       or the object may show a composite spectrum (possibly indicating a double star),
       or other weak indications of binarity, or the star has a (suspected) planetary companion

Field 21:
K_Delta_mu
Flag for the double-star nature of the object based on differences between
various proper motions (Wielen et al. 1999a):
        1 = single-star candidate
        2 = Delta_mu binary
    blank = uncertain (between 1 and 2),
            or the binary nature which is indicated by other data does
            not allow to classify the object as a single-star candidate

Field 22:
K_ae
Flag for 'astrometrically excellent stars' (see Section 5):
        3 = astrometrically excellent star with rank ***
        2 = astrometrically excellent star with rank **      
        1 = astrometrically excellent star with rank *   
    blank = star not classified as astrometrically excellent

Fields 23 -  32:
General remarks:
 The printed version and the print-analogue of the GC+HIP
contain for the other modes of the GC+HIP the proper motions and their mean
errors only. The positions, central epochs, and parallaxes derived for these
modes are given in the machine-readable version of the GC+HIP.

In order to save printing space, we give for the other modes of the GC+HIP,
i.e. the long-term prediction (LTP) and the short-term prediction (STP), and
for HIP (HIPPARCOS Catalogue) and GC, not the full quantities, but only
their differences, Delta = other mode - SI mode, with respect to the
single-star (SI) mode of the GC+HIP. These differences have to be added to
the results of the SI mode of the GC+HIP (Fields 7 and 8) in order to obtain
the results of the other modes. The data given for the GC and for
mu_0(GC) are given in the ICRS/HIPPARCOS system. Since the quantities for
the SI mode and all the differences Delta refer to the epoch and equinox
J2000.0 in the ICRS/HIPPARCOS system, this is then also the case for the full
results of the other modes.

The differences Delta are given for numerical and printing convenience only.
Therefore, the mean errors given in the GC+HIP Catalogue are not the errors of
these differences, but those of the full quantities in the other modes. The
mean errors given for the GC and for mu_0 include the mean errors
of the systematic differences between the GC system and the HIPPARCOS system.

Fields 23 - 27:
Delta_mu_alpha_*(LTP, STP, HIP, GC, mu_0(GC))
Difference Delta_mu_alpha_* between mu_alpha_* in the other solutions (LTP, STP, HIP, GC, mu_0)
and mu_alpha_* in the SI mode at epoch and equinox J2000.0. Units: mas/year.

Fields 28 - 32:
Delta_mu_delta (LTP, STP, HIP, GC, mu_0(GC))
Difference Delta_mu_delta between mu_delta in the other solutions (LTP, STP, HIP, GC, mu_0 (GC))
and mu_delta in the SI mode at epoch and equinox J2000.0. Units: mas/year.

Fields 33 - 37:
epsilon_mu_alpha_* (LTP, STP, HIP, GC, mu_0(GC))
Mean error epsilon_mu_alpha_* of mu_alpha_* of the star in
the solutions LTP, STP, HIP, GC, mu_0(GC). Units: mas/year.

Fields 38 - 42:
epsilon_mu_delta (LTP, STP, HIP, GC, mu_0(GC))
Mean error epsilon_mu_delta of mu_delta of the star in
the solutions LTP, STP, HIP, GC, mu_0(GC). Units: mas/year.

Field 43:
F_{FH}
F parameter based on the difference Delta_mu_{FH} = mu_F - mu_H between
the proper motions given by the FK5 (or RSup) and by HIPPARCOS.

Field 44:
F_{0H}
F parameter based on the difference Delta_mu_{0H} = mu_0 - mu_H between
the proper motion mu_0 (based on the stellar positions in the FK5 (or RSup)
and in the HIPPARCOS Catalogue) and the proper motion mu_H given by HIPPARCOS.

Field 45:
F_{0(GC)H}
F parameter based on the difference Delta_mu_{0(GC)H} = mu_0(GC) - mu_H between
the proper motion mu_0 (GC) (based on the stellar positions in the GC (Boss et al. 1937) and
in the HIPPARCOS Catalogue) and the proper motion mu_H given by HIPPARCOS.

Field 46:
F_{0F}
F parameter based on the difference Delta_mu_{0F} = mu_0 - mu_F between
the proper motion mu_0 (based on the stellar positions in the FK5 (or RSup)
and in the HIPPARCOS Catalogue) and the proper motion mu_F given by the FK5 (or RSup).

Field 47:
F_{TH}
F parameter based on the difference Delta_mu_{TH} = mu_T - mu_H between
the proper motion mu_T given in TYCHO2 Catalogue (Hoeg et al. 2000) and the
proper motion mu_H given by HIPPARCOS.

Field 48:
Number of an individual note
The number of the individual note refers to the notes given either in Part I of
the FK6 (Numbers 1-560, Wielen et al. 1999d) or in Part III of the FK6
(Numbers 3001-3024, Wielen et al. 2000).


Updated: 08 April 2002