The Transverse Peculiar Velocity of the Q2237+0305 Lens Galaxy and the Mean Mass of its Stars
Keywords:
galaxies: kinematics and dynamicsgravitational lensing: micro
methods: numerical
quasars: individual (Q2237+0305)
Issue Date:
2010-03-20Metadata
Show full item recordPublisher:
American Astronomical SocietyCitation:
Shawn Poindexter and Christopher S. Kochanek, "The Transverse Peculiar Velocity of the Q2237+0305 Lens Galaxy and the Mean Mass of its Stars," The Astrophysical Journal 712, no. 1 (2010), doi:10.1088/0004-637X/712/1/658Abstract:
Using 11 years of OGLE V-band photometry of Q2237+0305, we measure the transverse velocity of the lens galaxy and the mean mass of its stars. We can do so because, for the first time, we fully include the random motions of the stars in the lens galaxy in the analysis of the light curves. In doing so, we are also able to correctly account for Earth's parallax motion and the rotation of the lens galaxy, further reducing systematic errors. We measure a lower limit on the transverse speed of the lens galaxy, v_t > 338 km s^-1 (68% confidence) and find a preferred direction to the east. The mean stellar mass estimate, including a well-defined velocity prior, is 0.12 ≤ (M/Msun) ≤ 1.94 at 68% confidence, with a median of 0.52 Msun. We also show for the first time that analyzing subsets of a microlensing light curve, in this case the first and second halves of the OGLE V-band light curve, gives mutually consistent physical results.
Type:
ArticleISSN:
1538-4357Collections
Items in Knowledge Bank are protected by copyright, with all rights reserved, unless otherwise indicated.