GOSCAT - Galactic O Stars with Accurate Spectral Classes Catalog

Overview

The authors have produced a catalog of 378 Galactic O stars (the GOS Catalog) with accurate spectral classifications that is complete for V < 8 but includes many fainter stars. The catalog provides cross-identifications with other sources; coordinates (obtained in most cases from Tycho-2 data); astrometric distances for 24 of the nearest stars; optical (Tycho-2, Johnson, and Stroemgren) and NIR photometry; group membership, runaway character, and multiplicity information.

There is also a web-based version of this catalog with links to online services at http://www-int.stsci.edu/~jmaiz/research/GOS/GOSmain.html

Catalog Bibcode

2004ApJS..151..103M

References

A galactic O star catalog.
    Maiz-Apellaniz J., Walborn N.R., Galue H.A., Wei L.H.
   <Astrophys. J. Suppl. Ser., 151, 103-148 (2004)>
   =2004ApJS..151..103M

Provenance

This table was created by the HEASARC in February 2009 based on the electronic versions of Tables 1, 2, 5, 6, 8, 9, 10, 11, 12 and 13 obtained from the CDS, namely their catalog V/116 (files main.dat, posplx.dat, tyc2mmag.dat, ubvmag.dat and dist.dat).

Parameters

Supplement_Flag
This flag parameter is set to 'S' if the star is one of the 8 'supplement' O stars which have unresolved Wolf-Rayet companions.

Gos_Name
The GOS Catalog designation of the O star, as recommended by the CDS Dictionary of Nomenclature of Celestial Objects, using the 'GOS' prefix (for Galactic O stars) and the Galactic coordinates, followed by a running number to differentiate stars that are so close that they would otherwise have the same catalog name, e.g., 'GOS G287.64-00.68 02'.

HD_Number
The HD number of the O star.

HD_Component
The HD component identification for stars in multiple systems, listed as either capital letters or numerical identifications.

Tycho2_Name
The Tycho-2 Catalog designation for the O star. This catalog is used as the main source for positions in the GOS Catalog.

Wds_Name
The identification of the O star in the 2002 August Version of the Washington Double Star (WDS) Catalog.

Alt_Name
A common non-HD name for the O star, for those stars that do not have an HD catalog number or which are usually known by a name other than their HD designation.

Spect_Type
The spectral class of the O star, using the classification methodology discussed in Section 3 of the reference paper.

Spect_Type_Qualifier
The spectral type qualifier for the O star, as described in Table 4 of the reference paper.

Sec_Spect_Type
The spectral type of the 'secondary' component detected in the O star's spectrum, if any, or, for stars in the supplement (supplement_flag = 'S'), the spectral type of the Wolf-Rayet companion.

Ref_Spect_Type
This parameter contains a code indicating the reference from which the spectral type was taken, as follows:

  Value Reference          Authors(s)              CDS

  B97  1997ApJ...490..328B Burkholder et al.       Cat. <J/ApJ/490/328>
  D95  1995AJ....110.2235D Drissen et al.
  D99  1999AJ....117..354D de Zeeuw et al.         Cat. <J/AJ/117/354>
  F58  1958MNRAS.118..618F Feast
  G77  1977ApJS...35..111G Garrison et al.
  G82  1982ApJ...263..777G Garmany et al.          Cat. <II/82>
  G92  1992A&AS...94..211G Garmany & Stencel
  H01  2001A&A...365...49H Hoogerwerf et al.
  H64  ................... Haffner & Alter         1964, Trans. IAU, 12B, 336
  H77  1977AJ.....82..973H Heiser
  H93  1993AJ....106.1906H Hillenbrand et al.      Cat. <J/AJ/106/1906>
  H99  ................... Houk & Swift            Cat. <III/214>
  L68  1968ApJS...17..371L Lesh                    Cat. <III/23>
  L80  1980PASP...92..323L Levato & Malaroda
  M01  2001AJ....121.1050M Massey et al.
  M04  2004ApJS..151..103M Maiz-apellaniz et al.   This paper
  M53  1953ApJ...118..323M Morgan et al.
  M55  1955ApJS....2...41M Morgan et al.
  M76  1976AJ.....81..225M MacConnell & Bidelman
  M95  1995ApJ...454..151M Massey et al.           Cat. <J/ApJ/454/151>
  M98  1998AJ....115..821M Mason et al.
  N88  1988PASP..100.1436N Niemela & Morrison
  P02  2002ApJ...575.1050P Penny et al.
  S90  1990ApJ...358..229S Smith et al.
  S99  1999A&A...347..127S Schweickhardt et al.
  W00a 2000PASP..112...50W Walborn & Fitzpatrick
  W00b 2000PASP..112.1446W Walborn & Howarth
  W02a 2002AJ....123.2754W Walborn et al.
  W02b 2002AJ....124..507W Walborn
  W72  1972AJ.....77..312W Walborn
  W73  1973AJ.....78.1067W Walborn
  W74  1974ApJ...189..269W Walborn
  W76  1976ApJ...205..419W Walborn
  W80  1980ApJS...44..535W Walborn
  W81  1981ApJ...243L..37W Walborn
  W82  1982AJ.....87.1300W Walborn
  W90  1990MNRAS.243..662W Williams et al.
  W95  1995RMxAC...2...51W Walborn

Ref_Spect_Type_Table
The table number in the reference given in the ref_spect_type parameter from which the spectral classification was obtained.

Name
A commonly used name for the O star.

RA
The Right Ascension of the O star in the selected equinox. This was given in J2000.0 equatorial coordinates to a precision of 0.001 seconds of time in the original table. The Tycho-2 catalog was used as the primary reference for positions, given its precision (median astrometric errors of 7 mas for stars with V_T < 9), completeness (99% of all stars with V < ~11), and uniformity. Three hundred fifty-nine of the stars were found in the Tycho-2 catalog. Of those, 336 were present in the main catalog and had proper motion measurements (these are the stars with the most precise positions), and 14 were present in the main catalog but did not have their proper motion measured. The remaining nine Tycho stars were found in the first supplement (seven with proper motions and two without them) and their coordinates were precessed to epoch J2000.0.

For the 19 stars in the GOS catalog not included in the Tycho-2 catalog, the authors obtained their positions from other sources. Eleven of them were measured using a WFPC2 field that included Tycho-2 stars (used as a reference to correct the absolute astrometry), three were measured using ground-based images, one was listed in the USNO-A2.0 catalog, and four were obtained from the literature (see the ref_position parameter description below for more information). Those coordinates are expected to have in general a lower precision than the Tycho ones.

Dec
The Declination of the O star in the selected equinox. This was given in J2000.0 equatorial coordinates to a precision of 0.01 arcseconds in the original table.

LII
The Galactic Longitude of the O star.

BII
The Galactic Latitude of the O star.

Ref_Position
This parameter contain a code indicating the source reference for the position of the O star, as follows:

  Al = Secondary component of a multiple system measured with Aladin
  Ma = Massey et al. (2001AJ....121.1050M)
  NT = Measured from archival NTT data
  TA = Main Tycho-2 catalog, <I/259>, columns 5 and 6 (with proper motion)
  TB = Main Tycho-2 catalog, <I/259>, columns 28 and 29 (without proper motion)
  TC = Tycho-2 supplement 1, precessed to J2000.0 with proper motion
  TD = Tycho-2 supplement 1, precessed to J2000.0 without proper motion
  US = USNO-A2.0 data, Cat. <I/252>
  Va = van Altena & Jones (1972A&A....20..425V)
  Wa = Walborn et al. (2002AJ....124..507W)
  WF = WFPC2 data with absolute astrometry corrected using Tycho-2 stars.

HIP_Parallax
The Hipparcos parallax of the O star, in milliarcseconds. The vast majority (354 out of 378) of the O stars are beyond the range in which individual Hipparcos measurements are useful, i.e., most of the measurements suffer from Lutz-Kelker-type biases, as evidenced by the large fraction of values with large relative uncertainties (hip_parallax_error / hip_parallax) or with negative parallaxes.

HIP_Parallax_Error
The 1-sigma uncertainty in the O star's Hipparcos parallax, in milliarcseconds.

BT_Mag
The Tycho-2 B-band magnitude B_T of the O star. The Tycho-2 photometry is described in Hog et al. (2000, A&A, 357, 367); Hog et al. (2000, A&A, 355, L27). Two passbands, B_T and V_T, similar but not identical to Johnson's B and V passbands, were observed by the star mapper aboard the astrometric satellite Hipparcos between 1989.85 and 1993.21. Photometric typical uncertainties on V_T are 0.013 mag for V_T < 9 and 0.10 mag for the full catalog (which includes many fainter stars); individual uncertainties are provided for the value of B_T and V_T of each star. The main advantages of Tycho photometry are (1) its full sky coverage. (2) being obtained with a single instrument, (3) not being affected by atmospheric extinction, and (4) being obtained with a common reduction procedure. The GOS catalog includes V_T magnitudes and uncertainties for 359 stars and B_T magnitudes and uncertainties for 356 stars.

BT_Mag_Error
The 1-sigma uncertainty in the B_T magnitude of the O star.

VT_Mag
The Tycho-2 V-band magnitude V_T of the O star. The Tycho-2 photometry is described in Hog et al. (2000, A&A, 357, 367); Hog et al. (2000, A&A, 355, L27). Two passbands, B_T and V_T, similar but not identical to Johnson's B and V passbands, were observed by the star mapper aboard the astrometric satellite Hipparcos between 1989.85 and 1993.21. Photometric typical uncertainties on V_T are 0.013 mag for V_T < 9 and 0.10 mag for the full catalog (which includes many fainter stars); individual uncertainties are provided for the value of B_T and V_T of each star. The main advantages of Tycho photometry are (1) its full sky coverage. (2) being obtained with a single instrument, (3) not being affected by atmospheric extinction, and (4) being obtained with a common reduction procedure. The GOS catalog includes V_T magnitudes and uncertainties for 359 stars and B_T magnitudes and uncertainties for 356 stars.

VT_Mag_Error
The 1-sigma uncertainty in the V_T magnitude of the O star.

Jmag
The 2MASS J-band magnitude of the O star. The authors have included J, H, and K_s magnitudes only if two requirements were satisfied: (1) the 2MASS photometry for that passband had the best quality flag (A), indicating a valid measurement with SNR > 10 and a magnitude uncertainty < 0.10857; and (2) no other stars in the GOS catalog exist within a radius of 3" (this last requirement is included to avoid "mergers" in the data). With those restrictions, the GOS catalog includes 332, 339, and 344 stars with J, H, and K_s data, respectively. The values listed have been corrected for the zero-point offsets that Cohen et al. (2003, AJ, 126, 1090) measured in order to make them consistent with a number of other IR photometric systems. The corresponding uncertainties in the zero-point offsets have been added in quadrature to the measured ones.

Jmag_Error
The 1-sigma uncertainty in the J magnitude of the O star.

Hmag
The 2MASS H-band magnitude of the O star. The authors have included J, H, and K_s magnitudes only if two requirements were satisfied: (1) the 2MASS photometry for that passband had the best quality flag (A), indicating a valid measurement with SNR > 10 and a magnitude uncertainty < 0.10857; and (2) no other stars in the GOS catalog exist within a radius of 3" (this last requirement is included to avoid "mergers" in the data). With those restrictions, the GOS catalog includes 332, 339, and 344 stars with J, H, and K_s data, respectively. The values listed have been corrected for the zero-point offsets that Cohen et al. (2003, AJ, 126, 1090) measured in order to make them consistent with a number of other IR photometric systems. The corresponding uncertainties in the zero-point offsets have been added in quadrature to the measured ones.

Hmag_Error
The 1-sigma uncertainty in the H magnitude of the O star.

Kmag
The 2MASS K_s-band magnitude of the O star. The authors have included J, H, and K_s magnitudes only if two requirements were satisfied: (1) the 2MASS photometry for that passband had the best quality flag (A), indicating a valid measurement with SNR > 10 and a magnitude uncertainty < 0.10857; and (2) no other stars in the GOS catalog exist within a radius of 3" (this last requirement is included to avoid "mergers" in the data). With those restrictions, the GOS catalog includes 332, 339, and 344 stars with J, H, and K_s data, respectively. The values listed have been corrected for the zero-point offsets that Cohen et al. (2003, AJ, 126, 1090) measured in order to make them consistent with a number of other IR photometric systems. The corresponding uncertainties in the zero-point offsets have been added in quadrature to the measured ones.

Kmag_Error
The 1-sigma uncertainty in the K_s magnitude of the O star.

Vmag
The Johnson V-band magnitude of the O star. The sources and merging procedure for the Johnson magnitudes and colors given here are discussed in Section 5.1 of the reference paper.

Vmag_Error
The 1-sigma uncertainty in the V magnitude of the O star.

BV_Color
The Johnson (B-V) color of the O star. The sources and merging procedure for the Johnson magnitudes and colors given here are discussed in Section 5.1 of the reference paper.

BV_Color_Error
The 1-sigma uncertainty in the B-V color of the O star.

UB_Color
The Johnson (U-B) color of the O star. The sources and merging procedure for the Johnson magnitudes and colors given here are discussed in Section 5.1 of the reference paper.

UB_Color_Error
The 1-sigma uncertainty in the U-B color of the O star.

BY_Color
The Stromgren (b-y) color of the O star. The sources and merging procedure for the Stromgren colors and indices given here are discussed in Section 5.1 of the reference paper.

BY_Color_Error
The 1-sigma uncertainty in the b-y color of the O star.

M1_Index
The Stromgren m₁ index of the O star. The sources and merging procedure for the Stromgren colors and indices given here are discussed in Section 5.1 of the reference paper.

M1_Index_Error
The 1-sigma uncertainty in the Stromgren m₁ index.

C1_Index
The Stromgren c₁ index of the O star. The sources and merging procedure for the Stromgren colors and indices given here are discussed in Section 5.1 of the reference paper.

C1_Index_Error
The 1-sigma uncertainty in the Stromgren c₁ index.

Source_Flag
This parameter contains a flag [CMNW] which indicates that there are discrepancies in the optical photometry for the O star, as follows:

  M = Star deviated significantly from the general trend in
      (B_T - V_T) in the (V_T - V) against (B_T - V_T) plot.
  C = Star's color difference deviated from at least one of the trends
      in the "blue" minus "visual" colors (B_T - V_T), (B-V), and (b-y) plots.
  N = No discrepancy.
  W = Wolf-Rayet

Gos_Tyc_Offset_Limit
This parameter is set to '>' if the quoted angular distance (in arcseconds) from the given O star to the nearest star in the Tycho catalog is a lower limit.

Gos_Tyc_Offset
The angular distance (in arcseconds) from the given O star to the nearest star in the Tycho catalog.

Gos_Gos_Offset_Limit
This parameter is set to '>' if the quoted angular distance (in arcseconds) from the given O star to the nearest other O star in the GOS catalog is a lower limit.

Gos_Gos_Offset
The angular distance (in arcseconds) from the given O star to the nearest other O star in the GOS catalog.

Binary_Status
The O star's binary status, where 'SB1O' and 'SB2O' are well-known single-lined or double-lined spectroscopic binaries, respectively, 'SB1?' and 'SB2?' are their uncertain equivalents, 'C' are stars with apparent constant radial velocity, 'U' are stars with unknown status, and an 'E' suffix indicates an eclipsing or ellipsoidal variable.

Num_Astrometric_Cpt
The number of astrometric components for the O star.

Gos_Near_Cpt_Offset
The angular distance (in arcseconds) to the nearest astrometric component for the O star.

Gos_Far_Cpt_Offset
The angular distance (in arcseconds) to the furthest astrometric component for the O star.

Group_Membership
Information about the membership of the O star in a cluster or an OB association. Uncertain determinations are indicated with a colon.

The extent and reliability of this is extremely varied. For nearby stars, the most detailed study is that of de Zeeuw et al. (1999, AJ, 117, 354), who used a combination of positions, parallaxes, and proper motions to identify the membership of OB associations in the solar neighborhood. For stars located at farther distances, information is usually poorer and many times based only on position and spectroscopic distances (which themselves may be suspect). In some cases the only information present in the literature of the last 40 years is that of the original definition of OB Association nomenclature by the IAU. Given these problems, the authors decided to build this part of the GOS catalog with the approach of providing at least a tentative assignment for each star, knowing that future works may supersede their compilation. They used as a primary reference for group membership Mason et al. (1998, AJ, 115, 821) due to the large size of its sample, and they complemented it with a series of papers on individual clusters and associations (see the ref_notes parameter for these) and by Haffner & Alter (1964, Trans. IAU, 12B, 336). For those stars not referenced in those articles, they used the boundaries for associations established by Haffner & Alter (1964) to determine their membership tentatively (uncertain determinations are indicated by a colon). In those cases where a star is known to be part of a cluster or sub-association inside an association, both are listed. In this paper, the authors introduced the term of "Carina Nebula Association" to refer to the stars physically associated with that Nebula. Trumpler 14, Trumpler 16, and Collinder 228, as well as some stars in between those sub-associations, are included in that association: see Walborn (1995, RMAA, 2, 51) for a discussion of the stellar content of this region.

Runaway_Flag
This parameter is a flag which indicates the runaway (or not) character of the O star, as follows:

  1] Stars listed as runaways in Hoogerwerf et al., 2001A&A...365...49H
         or Mason et al., 1998AJ....115..821M, have a 'Y' for "yes"
  2] Other stars in clusters/associations or stars in Mason et al.,
         1998AJ....115..821M, not listed as runaways have a 'N' for "no".
  3] Other stars with "Field:" in the group_membership parameter have a
         'N' for "no:".

Ref_Codes
This parameter contains codes indicating the references for the group membership and runaway nature of the O star, as follows:

  Value Reference          Authors(s)              CDS

  B97  1997ApJ...490..328B Burkholder et al.       Cat. <J/ApJ/490/328>
  D95  1995AJ....110.2235D Drissen et al.
  D99  1999AJ....117..354D de Zeeuw et al.         Cat. <J/AJ/117/354>
  F58  1958MNRAS.118..618F Feast
  G77  1977ApJS...35..111G Garrison et al.
  G82  1982ApJ...263..777G Garmany et al.          Cat. <II/82>
  G92  1992A&AS...94..211G Garmany & Stencel
  H01  2001A&A...365...49H Hoogerwerf et al.
  H64  ................... Haffner & Alter         1964, Trans. IAU, 12B, 336
  H77  1977AJ.....82..973H Heiser
  H93  1993AJ....106.1906H Hillenbrand et al.      Cat. <J/AJ/106/1906>
  H99  ................... Houk & Swift            Cat. <III/214>
  L68  1968ApJS...17..371L Lesh                    Cat. <III/23>
  L80  1980PASP...92..323L Levato & Malaroda
  M01  2001AJ....121.1050M Massey et al.
  M04  2004ApJS..151..103M Maiz-apellaniz et al.   This paper
  M53  1953ApJ...118..323M Morgan et al.
  M55  1955ApJS....2...41M Morgan et al.
  M76  1976AJ.....81..225M MacConnell & Bidelman
  M95  1995ApJ...454..151M Massey et al.           Cat. <J/ApJ/454/151>
  M98  1998AJ....115..821M Mason et al.
  N88  1988PASP..100.1436N Niemela & Morrison
  P02  2002ApJ...575.1050P Penny et al.
  S90  1990ApJ...358..229S Smith et al.
  S99  1999A&A...347..127S Schweickhardt et al.
  W00a 2000PASP..112...50W Walborn & Fitzpatrick
  W00b 2000PASP..112.1446W Walborn & Howarth
  W02a 2002AJ....123.2754W Walborn et al.
  W02b 2002AJ....124..507W Walborn
  W72  1972AJ.....77..312W Walborn
  W73  1973AJ.....78.1067W Walborn
  W74  1974ApJ...189..269W Walborn
  W76  1976ApJ...205..419W Walborn
  W80  1980ApJS...44..535W Walborn
  W81  1981ApJ...243L..37W Walborn
  W82  1982AJ.....87.1300W Walborn
  W90  1990MNRAS.243..662W Williams et al.
  W95  1995RMxAC...2...51W Walborn

Class
The HEASARC Browse O star classification, based on the spect_type parameter.

Contact Person

Questions regarding the GOSCAT database table can be addressed to the HEASARC User Hotline.

Page Author: Browse Software Development Team
Last Modified: Thursday, 13-Apr-2017 18:32:12 EDT