Peculiar velocity flow field in the Zone of Avoidance Khaled Said - - PowerPoint PPT Presentation

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Peculiar velocity flow field in the Zone of Avoidance Khaled Said - - PowerPoint PPT Presentation

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at low Galactic latitude Peculiar velocity flow field in the Zone of Avoidance Khaled Said Large Scale Structure and Galaxy Flows, Tuesday, July 5, 2016 Supervisors: Rene C. Kraan-Korteweg & Thomas H. Jarrett (UCT)

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SLIDE 1

Peculiar velocity flow field in the Zone of Avoidance Khaled Said

  • Large Scale Structure and Galaxy Flows, Tuesday, July 5, 2016
  • Supervisors: Renée C. Kraan-Korteweg & Thomas H. Jarrett (UCT)
  • Lister Staveley-Smith (ICRAR, UWA)
  • Collaborators: W. Williams, C. Springob, A. Schröder, W. van Driel & P. Henning

at low Galactic latitude

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SLIDE 2

Motivation?

CF-3; Tully et al (2016) 6df; Springob et al (2014) 2MTF; Hong et al (2014)

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SLIDE 3

How we map these galaxies?

  • 1. Calibrated TF relation to work in the ZOA
  • 2. Follow-up NIR observations of HIZOA galaxies
  • 3. 21-cm HI observations of the edge-on galaxies in

the NIR imaging

  • 4. Measuring distances and peculiar velocities
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SLIDE 4

Why isophotal and not total magnitude?

l

Depth of 2MASS survey.

l

IRSF (0.45''/pix) & 2MASS (2''/ pix)

l

Difficulty to determine total magnitude in ZoA even with IRSF survey.

l

High offsets between 2MASS and IRSF in total magnitude (create artificial peculiar velocity).

l

Sample of 66 galaxies in ZoA.

Said, Kraan-Korteweg & Jarrett (2015)

  • 1. Calibrate TF relation to work in the ZoA
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SLIDE 5
  • 1. Calibrate TF relation to work in the ZoA

Said, Kraan-Korteweg & Jarrett (2015)

Sample of 888 galaxies used in

  • 2MTF. I (Masters et al. 2008)
  • Bias correction:
  • 1. Morphological correction.
  • 2. Incompleteness Bias.
  • 3. Cluster Size Bias.
  • Mean Distances to Cluster.
  • Sample Incompleteness.
  • 4. Cluster Peculiar velocity.
  • K-Correction:
  • Internal Extinction:
  • Galactic Extinction:

nearly identical Less scatter

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SLIDE 6
  • 1. Calibrated TF relation to work in the ZOA
  • 2. Follow-up NIR observations of HIZOA galaxies
  • 3. 21-cm HI observations of the edge-on galaxies in

the NIR imaging

  • 4. Measuring distances and peculiar velocities

Outline!

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SLIDE 7
  • 2. Follow-up NIR imaging of HIZOA

A total of 12 weeks were allocated exclusively to this project.

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SLIDE 8
  • 2. Follow-up NIR imaging of HIZOA

A total of 12 weeks were allocated exclusively to this project.

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SLIDE 9

Photometry:

  • 1. Find the galaxy.
  • 2. Run star-subtraction.
  • 3. Run photometry pipe-line.
  • Results:

ellipticity, isophotal radius, isophotal magnitude, central surface brightness, stellar density.

  • 2. Follow-up NIR imaging of HIZOA

Said et al., submitted

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SLIDE 10
  • 2. Follow-up NIR imaging of HIZOA

Said et al., submitted

  • 1. IRSF vs. 2MASS (285 galaxies)
  • 2. IRSF vs. UKIDSS (30 galaxies; NE)

Comparisons

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SLIDE 11
  • 2. Follow-up NIR imaging of HIZOA

Said et al., submitted

  • 1. IRSF vs. 2MASS (285 galaxies)
  • 2. IRSF vs. UKIDSS (30 galaxies; NE)

Comparisons

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SLIDE 12

How we map these galaxies?

  • 1. Calibrated TF relation to work in the ZOA
  • 2. Follow-up NIR observations of HIZOA galaxies
  • 3. 21-cm HI observations of the edge-on galaxies in

the NIR imaging

  • 4. Measuring distances and peculiar velocities
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SLIDE 13
  • 3. 21cm HI Follow-up of the NIR follow-up of the HIZOA
  • 300 hours on Parkes radio

telescope

  • High Quality (HQ) narrow-

band observations of 238 galaxies and 104 additional HIZOA galaxies with HQ H I profiles

  • Blue >>> Staveley-Smith et

al (2016) Green >>> Donley et al (2005) Red >>> Kraan-Korteweg (in prep.)

Said et al., (2016)

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SLIDE 14
  • 3. 21cm HI Follow-up of the NIR follow-up of the HIZOA

Said et al., (2016)

Comparison

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SLIDE 15
  • 3. 21cm HI Follow-up of the NIR follow-up of the HIZOA

Said et al., (2016)

Comparison

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SLIDE 16

How we map these galaxies?

  • 1. Calibrated TF relation to work in the ZOA
  • 2. Follow-up NIR observations of HIZOA galaxies
  • 3. 21-cm HI observations of the edge-on galaxies in

the NIR imaging

  • 4. Measuring distances and peculiar velocities
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SLIDE 17
  • 4. Measuring Peculiar Velocities (PRELIMINARY)

in progress

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SLIDE 18
  • 4. Measuring Peculiar Velocities (PRELIMINARY)

work in progress

Selection bias

  • Inhomogeneous Malmquist bias (negligible)
  • homogeneous Malmquist bias
  • A. volume effect
  • B. selection effect
  • Same Method as in Springob et al. (6df;2014 & 2MTF; 2015)
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SLIDE 19
  • 4. Measuring Peculiar Velocities (PRELIMINARY)

in progress

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SLIDE 20
  • 4. Measuring Peculiar Velocities (PRELIMINARY)

in progress

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SLIDE 21

Summary & take home messages

  • T-F Template relation (Said et al. 2015, MNRAS, 447, 1618);

less scatter than 2MTF. I (for small galaxies, log W < 2.5)

  • NIR observations using the IRSF telescope in SA (Said et al.,

submitted); NIR photometry for over a thousand galaxies in the ZOA (catalog and Fits files will be available)

  • 21cm radio observation using Parkes telescope in AU (Said

et al. 2016, MNRAS, 457, 2366); 342 galaxies with S/N > 5 (catalog and Fits files are available)

  • Distance and Peculiar velocity calculations; Work still in

progress (stay tuned)

  • Extend to Northern sky using Nancay & UKIDSS data; Anja

Schröder talk

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SLIDE 22

Extra slides

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SLIDE 23
  • 2. Follow-up NIR imaging of HIZOA

Said et al., submitted

Completeness

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SLIDE 24
  • 4. Measuring Peculiar Velocities (PRELIMINARY)

in progress

Same Method as in Springob et al. (2014, 2015)

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SLIDE 25