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Pizza Lunch

Pizza Lunch. Galaxy-Halo Gas Kinematic Connection at 0.3 < z < 1. Diffuse Ionized Gas (DIG). Rand (2000). NGC 5775 H α map. D = 24.8 Mpc It is an interacting galaxy. Diffuse Ionized Gas (DIG). DIG detected out to 13 kpc Gas approaches the systemic velocity of the galaxy.

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Pizza Lunch

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  1. Pizza Lunch Galaxy-Halo Gas Kinematic Connection at 0.3 < z < 1

  2. Diffuse Ionized Gas (DIG) Rand(2000) • NGC 5775 Hα map. • D = 24.8 Mpc • It is an interacting galaxy

  3. Diffuse Ionized Gas (DIG) • DIG detected out to 13 kpc • Gas approaches the systemic velocity of the galaxy. • Implies that the gas is decreasing in rotational velocity and have no rotational above several kpcs. Rand(2000)

  4. HI Halos • D = 9.5 Mpc • Neutral hydrogen map from WSRT • Presence of an H I halo extending up to at least 5 kpc from the plane Swaters et al. (1997)

  5. HI Halos Disk gas Halo gas Halo gas appears to rotate 25 to 100 km s-1 more slowly than the gas in the plane.      Swaters et al. (1997)

  6. Lagging HI Halos The channel radial velocities run in steps of 33 km/s from systemic (528 km/s heliocentric) at the top to near rotational (299 km/s heliocentric) at the bottom. Swaters et al. (1997)

  7. Lagging HI Halos & Forbidden Gas Fraternali et al. (2002) The total mass of the anomalous gas is 3×108 Msun (of which just 6−7×106 Msun forbidden), which corresponds to 10% of the total H I mass of NGC 2403.

  8. Halo Gas Model

  9. How Far is Too Far? DSS overlaid column densities • Halos of nine galaxies (with redshifts cz < 6000 kms−1) were probed at large galactocentric radii using background quasars. • The projected quasar-galaxy separations range from 55 to 387 h−175 kpc. • Lyα absorption lines were successfully detected in the spectra of five quasars and in each case at wavelengths consistent with the galaxy’s redshift. • HI velocity fields were obtained at the VLA for three of the galaxies in our sample to derive their rotation curves. Cotéet al. (Astroph 410288)

  10. Cotéet al. (Astroph 410288) Halo Gas at Large Radii Lyα

  11. Halo Gas at Large Radii It is very difficult to explain the observed Lyα velocity as due to gas in an extended rotating disk. In most cases one would need to invoke large warps in the outer gas disks and also thick gas disks in order to reconcile the observed velocities with the predicted ones. Lyα

  12. Halo Gas at Large Radii or Cosmic Web The cosmic web is the most likely origin for the detected Ly lines. Observations confirm the Bowen et al. (2002) correlation of equivalent widths with the local volume density of galaxies around the sightline, and the observed equivalent widths of the lines are consistent with expectations of the cosmic web. Cotéet al. (Astroph 410288)

  13. Questions • How far can we measure the kinematics of haloes? • How do the kinematics of the stellar component reflect that of the halo • kinematics? • What role does morphology and star formation history play? • Do disturbed galaxies have more enriched haloes?

  14. Galaxy-Halo Gas Kinematic Connection at 0.3 < z < 1 Glenn Kacprzak NMSU Collaborators: Chris Churchill NMSU Chuck Steidel Caltech

  15. Method & Goals • Study Mg II quasar absorption line systems in order to understand the kinematics of halos probing distances out to 70 kpcs from the galaxies. • Therefore the galaxies in our sample are selected by the known presence of Mg II absorption • Determine whether the galaxy kinematics and/or morphologies are coupled to the halo kinematics • Our main goal is to determine how early epoch galaxy halos are built and sustained.

  16. Quasar Spectra & Intervening Galaxies Mg II 2796, 2803

  17. High Resolution Spectra 2796 2803 Mg II 2796, 2803

  18. Quasar Spectra of Intervening Galaxies Velocity km s-1 Sample includes absorbers with W(2796) < 1

  19. UnderStanding Galaxies is the Key Selected 5 edge-on galaxies 4 of the 5 showed the trend for the halo gas kinematics follows that of the galaxies What is needed is a larger sample which represents a broad range of orientations with respect to the quasar line of sight Steidel et al. (2002)

  20. HST WFPC-2 5” z = 0.374 z = 0.298 z = 0.346 z = 0.368 z = 0.317 Orientated such that the QSO is down 5” z = 0.418 z = 0.442 z = 0.472 z = 0.494 z = 0.437 z = 0.525 z = 0.550 z = 0.551 z = 0.553 z = 0.591 z = 0.640 z = 0.656 z = 0.661 z = 0.729 z = 0.787 z = 0.797 z = 0.851 z = 0.888 z = 0.888 z = 0.891

  21. Halo Gas Absorption Strength Correlated to Oriention of Galaxies? PA = 45o i = 0o PA = 45o i = 30o PA = 0o i = 0o PA = N/A i = 90o cos(PA)cos(i) = 0.61 cos(PA)cos(i) = 1.0 cos(PA)cos(i) = 0.0 QSO Intensity Velocity

  22. Co-rotating Disk Gas & Oriention of Galaxies “Normal” Absorbers Wind Dominate & DLA Systems

  23. Impact Parameter & Absorption

  24. z = 0.374 z = 0.298 z = 0.346 z = 0.368 z = 0.317 z = 0.418 z = 0.442 z = 0.472 z = 0.494 z = 0.437 z = 0.525 z = 0.550 z = 0.551 z = 0.553 z = 0.591 z = 0.640 z = 0.656 z = 0.661 z = 0.729 z = 0.787 z = 0.797 z = 0.851 z = 0.888 z = 0.888 z = 0.891

  25. Galaxy Models: GIM2D Simard et al. (2002) N E HST Galaxies Model Images Residual Images

  26. GIM2D: Galaxy Asymmetry HST Image Model Model Residual RA33 RT > 0.05 Barred Spiral Structure! If more than 5% of the galaxies total residual flux is due to asymmetries then these galaxies are considered to not be “normal”; they are “asymmetric”. Schade et al. (1995)

  27. Asymmetry & Absorption Strength Asymmetric Galaxies “Normal” Galaxies “Normal” Absorbers Wind Dominate & DLA Systems

  28. Summary • Halo gas is “aware” of the kinematics of the galaxy (pilot study 5 galaxies). • There are no clear trends between absorption strength and orientation of the galaxy. More detailed models are needed. • Minor morphological perturbations are correlated to absorption strength. This may suggest that most Mg II absorption selected galaxies have had some previous minor interactions or harassments. Future Work • 21 of 25 Keck HIRES spectra are in hand and are currently being analyzed. The remaining quasar spectra will be obtained in the near future. • Obtain redshifts of remaining candidates in order to increase sample size to over 50. • Obtain rotation curves of the galaxy using Gemini and Keck.

  29. Some Cases are Complicated... MC 1331+170 zabs = 0.7 Ellison et al. (2003) Forbidden Gas Lagging Halo Swaters et al. (1997) Schaap et al. (2000) Sancisi et al. (2001) Fraternali et al. (Yesterday)

  30. Halo Gas: Simple Kinematic Model Asymmetric Blended Line Morphology Symmetric Resolved Line Morphology Observed spectra contain an admixture of both models

  31. HIRES/Kinematics

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