IANIGLA   20881
INSTITUTO ARGENTINO DE NIVOLOGIA, GLACIOLOGIA Y CIENCIAS AMBIENTALES
Unidad Ejecutora - UE
artículos
Título:
Kinematics and velocity ellipsoid of the F giants
Autor/es:
BRANHAM, RICHARD L. JR.
Revista:
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
Editorial:
WILEY-BLACKWELL PUBLISHING, INC
Referencias:
Año: 2010 vol. 409 p. 1269 - 1280
ISSN:
0035-8711
Resumen:
To study the kinematics of the F giant stars (luminosity class III), proper motions taken from
van Leeuwens new reduction of the Hipparcos catalogue are used. 591 stars, of which 222
have radial velocities, were used in the final study. Semi-definite programming solves for the
kinematical parameters such as the Oort constants and simultaneously for the coefficients of
the velocity ellipsoid. The condition that the solution for the solar velocity calculated both
from the kinematical parameters and from the velocity ellipsoid calculation should be the
same is enforced. The truncated singular value decomposition allows one to incorporate into
the velocity ellipsoid determination tangential velocities for which there are no corresponding
radial velocities. The solution gives solar velocity of 18.52 } 0.48 km s−1 ; Oorts constants,
in units of km s−1 kpc−1, A = 14.85 } 7.47 and B = −10.85 } 6.83, implying a rotational
velocity of 210.68 } 29.66 km s−1 if we take the distance to the Galactic Centre as 8.2 }
velocity of 210.68 } 29.66 km s−1 if we take the distance to the Galactic Centre as 8.2 }
in units of km s−1 kpc−1, A = 14.85 } 7.47 and B = −10.85 } 6.83, implying a rotational
velocity of 210.68 } 29.66 km s−1 if we take the distance to the Galactic Centre as 8.2 }
velocity of 210.68 } 29.66 km s−1 if we take the distance to the Galactic Centre as 8.2 }
have radial velocities, were used in the final study. Semi-definite programming solves for the
kinematical parameters such as the Oort constants and simultaneously for the coefficients of
the velocity ellipsoid. The condition that the solution for the solar velocity calculated both
from the kinematical parameters and from the velocity ellipsoid calculation should be the
same is enforced. The truncated singular value decomposition allows one to incorporate into
the velocity ellipsoid determination tangential velocities for which there are no corresponding
radial velocities. The solution gives solar velocity of 18.52 } 0.48 km s−1 ; Oorts constants,
in units of km s−1 kpc−1, A = 14.85 } 7.47 and B = −10.85 } 6.83, implying a rotational
velocity of 210.68 } 29.66 km s−1 if we take the distance to the Galactic Centre as 8.2 }
velocity of 210.68 } 29.66 km s−1 if we take the distance to the Galactic Centre as 8.2 }
in units of km s−1 kpc−1, A = 14.85 } 7.47 and B = −10.85 } 6.83, implying a rotational
velocity of 210.68 } 29.66 km s−1 if we take the distance to the Galactic Centre as 8.2 }
velocity of 210.68 } 29.66 km s−1 if we take the distance to the Galactic Centre as 8.2 }
Hipparcos catalogue are used. 591 stars, of which 222
have radial velocities, were used in the final study. Semi-definite programming solves for the
kinematical parameters such as the Oort constants and simultaneously for the coefficients of
the velocity ellipsoid. The condition that the solution for the solar velocity calculated both
from the kinematical parameters and from the velocity ellipsoid calculation should be the
same is enforced. The truncated singular value decomposition allows one to incorporate into
the velocity ellipsoid determination tangential velocities for which there are no corresponding
radial velocities. The solution gives solar velocity of 18.52 } 0.48 km s−1 ; Oorts constants,
in units of km s−1 kpc−1, A = 14.85 } 7.47 and B = −10.85 } 6.83, implying a rotational
velocity of 210.68 } 29.66 km s−1 if we take the distance to the Galactic Centre as 8.2 }
velocity of 210.68 } 29.66 km s−1 if we take the distance to the Galactic Centre as 8.2 }
in units of km s−1 kpc−1, A = 14.85 } 7.47 and B = −10.85 } 6.83, implying a rotational
velocity of 210.68 } 29.66 km s−1 if we take the distance to the Galactic Centre as 8.2 }
velocity of 210.68 } 29.66 km s−1 if we take the distance to the Galactic Centre as 8.2 }
} 0.48 km s−1 ; Oorts constants,
in units of km s−1 kpc−1, A = 14.85 } 7.47 and B = −10.85 } 6.83, implying a rotational
velocity of 210.68 } 29.66 km s−1 if we take the distance to the Galactic Centre as 8.2 }
velocity of 210.68 } 29.66 km s−1 if we take the distance to the Galactic Centre as 8.2 }
−1 kpc−1, A = 14.85 } 7.47 and B = −10.85 } 6.83, implying a rotational
velocity of 210.68 } 29.66 km s−1 if we take the distance to the Galactic Centre as 8.2 }} 29.66 km s−1 if we take the distance to the Galactic Centre as 8.2 }
1.1 kpc; velocity dispersions, in units of km s−1, of óx = 36.89 } 1.90, óy = 24.66 } 1.16,−1, of óx = 36.89 } 1.90, óy = 24.66 } 1.16,
óz = 17.97 } 0.81 with a vertex deviation of −16. ◦ 54 } 14. ◦ 88.z = 17.97 } 0.81 with a vertex deviation of −16. ◦ 54 } 14. ◦ 88.