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J/A+A/325/647      High-resolution spectra south of Taurus    (Neuhaeuser+ 1997)
================================================================================
Optical high-resolution spectroscopy of ROSAT detected
late-type stars south of the Taurus molecular clouds
       Neuhauser R., Torres G., Sterzik M.F., Randich S.
      <Astron. Astrophys. 325, 647 (1997)>
      =1997A&A...325..647N      (SIMBAD/NED BibCode)
================================================================================
ADC_Keywords: Stars, late-type ; Radial velocities ; Rotational velocities
Keywords: stars: formation - stars: late-type - stars: pre-main sequence -
          X-rays: stars
Mission_Name: ROSAT

Description:
    Listed are results from our high-resolution data for all stars in our
    study area which were listed by either Magazzu et al.
    (1997A&AS..124..449M) or Alcala et al. (1996A&AS..119....7A), i.e.
    T Tauri candidates from the ROSAT All-Sky Survey. In table 1, we list
    all stars for which lithium was found either by Magazzu et al.
    (1997A&AS..124..449M) or in our CASPEC spectra, as well as two stars
    identified as wTTS by Alcala et al. (1996A&AS..119....7A). Listed are
    the designation, number of single-order echelle spectra taken,
    effective temperatures, projected rotational velocities, mean
    heliocentric radial velocities with errors, radial velocities in the
    local standard of rest, and remarks on variability in radial velocity
    as found in our high-resolution spectra. For comparison, we also list
    the results on spectral types of the stars (with `e' for H{alpha}
    emission) as found by Magazzu et al. (1997A&AS..124..449M) (or Alcala
    et al., 1996A&AS..119....7A) with low- and medium-resolution
    spectroscopy. In the last two columns, we list the (NLTE) lithium
    abundance (given on a scale where logN(H)=12) and the lithium excess
    above the relevant Pleiades upper envelope; upper limits indicate
    stars where the Magazzu et al. (1997A&AS..124..449M) spectra suffer
    from either low S/N or low resolution. In table 2, we list all stars
    where no lithium was detected -- neither by Magazzu et al.
    (1997A&AS..124..449M) nor in our CASPEC spectra.

File Summary:
--------------------------------------------------------------------------------
  FileName   Lrecl  Records   Explanations
--------------------------------------------------------------------------------
ReadMe          80        .   This file
table1          89       56   High-resolution data for lithium-rich ROSAT
                               source counterparts
table2          78       55   High-resolution data for ROSAT sources with
                               undetected lithium
--------------------------------------------------------------------------------

Byte-by-byte Description of file: table1
--------------------------------------------------------------------------------
   Bytes Format Units    Label        Explanations
--------------------------------------------------------------------------------
   1- 16  A16   ---      Name         Name of objects (1)
  18- 19  I2    ---      No           Number of high-resolution observations
  22- 25  I4    K        Teff         ? Effective temperature
  27- 29  I3    km/s     vsini        ? Rotational velocity v sin i
  32- 36  F5.1  km/s     HRV          ? Heliocentric radial velocity
  39- 42  F4.1  km/s   e_HRV          ? Error in radial velocity
  45- 49  F5.1  km/s     RVlsr        ? Local-standard-of-rest radial velocity
  52- 59  A8    ---      Rem          Remarks (2)
  61- 71  A11   ---      M97          Results from Magazzu et al.
                                       (1997A&AS..124..449M) (3)
  73- 75  F3.1 [Sun]     NLi          ? log of Lithium abundance N(Li)
      76  A1    ---    n_NLi          [?] Unknown value
  78- 82  F5.2  0.1nm    dEW(Li)      ? Lithium excess above ZAMS level
      83  A1    ---    n_dEW(Li)      [?] Unknown value
  85- 88  F4.2  0.1nm    ULdEW(Li)    ? Upper limits on Lithium excess above
                                         ZAMS level
--------------------------------------------------------------------------------
Note (1):
   Row 1 to   9: K-type stars with lithium excess south of Taurus:
                 PMS stars younger than 30 million years
   Row 10 to 18: K-type stars located on lambda Ori with lithium excess:
                 PMS stars younger than 30 million years
   Row 19 to 33: F8- to G9-type stars with lithium excess:
                 ZAMS stars older than 30 million years
   Row 34 to 40: Lithium upper limits due to low S/N or low-resolution spectra
   Row 41 to 56: Stars with lithium, but without lithium excess:
                 ZAMS stars older than 100 million years
Note (2): SB 1 or 2: single- or double-lined spectroscopic binaries.
Note (3): (N): Listed as "wTTS" in Neuhaeuser et al. (1995A&A...299L..13N)
          (1): Spectral type given by Alcala et al. (1996A&AS..119....7A), who
                identified these stars as wTTS.
          (2): SB as found in our CASPEC spectrum; components NW and SE are
                separated by 14 arcsec (Magazzu et al., 1997A&AS..124..449M)
          (3): SB as found by Magazzu et al. (1997A&AS..124..449M), who found
                lithium in both components; data given here are for the primary,
                which is much brighter.
          (4): We have revised EW(Li) down to 0.25 Angstrom from the value given
                in Magazzu et al. (1997A&AS..124..449M), which apparently was
                too large due to an incorrect assumption on the continuum level.
          (5): Classified as a wTTS by N95c, but as a dKe star by Magazzu et al.
                (1997A&AS..124..449M); we detect lithium in our CASPEC spectrum
                but not in excess of the Pleiades level, and conclude that this
                star is a K5 ZAMS star.
          (6): Magazzu et al. (1997A&AS..124..449M) detected lithium, but did
                not classify this star as `PMS' or `PMS?'.
          (7) Lithium data from our high-resolution CASPEC spectra.
          (8) Orbit known (Torres et al., in preparation).
--------------------------------------------------------------------------------

Byte-by-byte Description of file: table2
--------------------------------------------------------------------------------
   Bytes Format Units    Label      Explanations
--------------------------------------------------------------------------------
   1- 16  A16   ---      Name       Name of objects
  18- 19  I2    ---      no         Number of high-resolution observations
  22- 25  I4    K        Teff       ? Effective temperature
  27- 29  I3    km/s     vsini      ? Rotational velocity v sin i
  31- 33  I3    km/s     ULvsini    ? Upper limit on v sin i
  35- 39  F5.1  km/s     HRV        ? Heliocentric radial velocity
  42- 45  F4.1  km/s   e_HRV        ? Error in radial velocity
  48- 52  F5.1  km/s     RVlsr      ? Local-standard-of-rest radial velocity
  55- 63  A9    ---      remarks    Remarks (1)
  66- 72  A7    ---      M97        Results from Magazzu et al.
                                     (1997A&AS..124..449M)
--------------------------------------------------------------------------------
Note (1): SB 1 or 2: single- or double-lined spectroscopic binaries.
          If "orbit" is given, then the orbit is known (Torres et al., in prep.)
          (1): Lines in high-resolution spectra are too broad to obtain
                reliable data.
--------------------------------------------------------------------------------

Acknowledgements: Ralph Neuhaeuser <rne@rosat.mpe-garching.mpg.de>
================================================================================
(End)          Ralph Neuhaeuser [MPE Garching], Patricia Bauer [CDS] 22-Jul-1997

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