CDROM/AJ/V113/P0321 Stellar Kinematics (Tiede & Terndrup 1997) ================================================================================ A New Survey of Stellar Kinematics in the Central Milky Way Glenn P. Tiede and D. M. Terndrup <1997, AJ, 113, 321> =1997AJ....113..321T ================================================================================ Abstract: We present the results of a photometric and spectroscopic study of 189 stars in a field at (l,b)=(8.4 deg,-6.0 deg). We measure radial velocities and selected indices of line strength from the spectra and derive reddening, metallicity, photometric parallaxes, and azimuthal rotation velocities and dispersion. We find an average reddening and extinction to the field of E(V-I)=0.43+/-0.09 and A_V=1.07+/-0.22. We use distances derived from photometric parallaxes and find that the distribution of stars along this line of sight is not strongly peaked at the tangent point. In an attempt to understand the apparent decrease in line-of-sight velocity dispersion with increasing metallicity, we divide our sample into metal-rich and metal-poor groups. Though we lack enough stars to statistically analyze each group, we find the average distances of the metal-rich and metal-poor groups to be, =3.1 kpc and =7.0 kpc. Excluding stars in our sample which are likely to be in the foreground disk, we calculate a rotational velocity for the bulge of Vrot=97+/-9 km/s, sigma_phi=71+/-11 km/s. Combining this result with studies at other (l,b), we find a rotation rate for the bulge of 10.6+/-0.6 km/s/deg or 77+/-5 km/s/kpc. We conclude that when attempting to understand the properties of stars along lines of sight into the bulge it is important to consider the line-of-sight distribution of the stars, especially when more than a few degrees from the galactic center. (Copyright) 1997 American Astronomical Society. File Summary: -------------------------------------------------------------------------------- File Name Lrecl Records Explanations -------------------------------------------------------------------------------- table1.dat 80 189 Astrometry, photometry, radial velocity, and distance modulus table1.tex 104 211 AASTeX version of table1.dat table3.dat 47 189 Transformed indices and calculated [Fe/H] table3.tex 80 208 AASTeX version of table3.dat -------------------------------------------------------------------------------- Byte-by-byte Description of file: table1.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 3 I3 --- Star Star number 4- 6 I3 h RAh Right ascension, epoch J1950 7 1X --- --- Always ':' 8- 9 I2 min RAm R.A. 10 1X --- --- Always ':' 11-15 F5.2 s RAs R.A. 16 1X --- --- Blank 17 A1 --- DE- Declination sign 18-19 I2 deg DEd Declination, epoch J1950 20 1X --- --- Always ':' 21-22 I2 arcmin DEm Dec. 23 1X --- --- Always ':' 24-28 F5.2 arcsec DEs Dec. 29-36 F8.3 mag V V magnitude 37-42 F6.3 mag e_V Error in V 43-49 F7.3 mag V-I V-I color 50-55 F6.3 mag e_V-I Error in V-I 56-62 F7.1 km/s v_h []? Heliocentric radial velocity 63-68 F6.1 km/s e_v_h []? Error in v_h 69-75 F7.2 mag DMod []? Distance modulus, (m-M)_0 76-80 F5.2 mag e_DMod []? Error in DMod -------------------------------------------------------------------------------- Byte-by-byte Description of file: table3.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 3 I3 --- Star Star number 4- 9 F6.2 --- Fe5270 Fe5270 index 10-14 F5.2 --- e_Fe5270 Error in Fe5270 15-20 F6.2 --- Fe5335 Fe5335 index 21-25 F5.2 --- e_Fe5335 Error in Fe5335 26-31 F6.2 --- Hbeta []? Hbeta index 32-36 F5.2 --- e_Hbeta []? Error in Hbeta 37-42 F6.2 --- Fe_H []? Metallicity [Fe/H] 43-47 F5.2 --- e_Fe_H []? Error in Fe_H -------------------------------------------------------------------------------- ================================================================================ (End) Lee Brotzman [ADS] 04-Apr-1997