HI in the Interacting Pair NGC 4618/4625

HI in the Interacting Pair NGC 4618/4625

HI in the Interacting Pair NGC 4618/4625 Stephanie J. Bush Case Western Reserve University What's so exciting? Why do we care about NGC 4618/4625?

Why neutral hydrogen? intermediate masses we can observe it!

lopsided galaxies Interactions often more extended and

possibly more massive distributions than stars more sensitive to interactions Objectives We hope to calculate:

spatial distribution masses rotation curves

Interaction history HI Detection 101 HI gives off radio emission

with a 21 cm wavelength Higher column density HI gives off more emission Doppler shift gives velocities Can display channels as a movie or as a sum http:///burro.cwru.edu/Academics/Astr222/Galaxy/Structure/gas.html So how about some data?

A quick optical glimpse... Sloan Digital Sky Survey Total HI distribution NGC 4618 Spatial Analysis

Intensity vs. radius plots Adopting 6 Mpc distance and effective radii (Odewahn 1991) we find... Extent

4618: 4 x effective radii 4625: 9 x effective radii HI mass 4618: (5.3 +/- 0.6) x 108 Msun

4625: (3.9 +/- 0.6) x 108 Msun NGC 4625 Dynamical Analysis: Velocity Field Dynamical Analysis: Rotation Curve for NGC 4618

Preliminary Dynamical Mass: 4.1 x 109 M sun Dynamical Analysis: Rotation Curve for NGC 4625 Preliminary dynamical mass: 8.2 x 108 Msun Future work (Preferably, in the next week...)

Dynamical masses with more detailed halo models, perhaps including a disk model Interaction history: What constraints can we put on the galaxies being bound or unbound? If they are bound what will the merger remnant look like? Compare with other pairs of galaxies (perhaps NGC 672 - IC 1727) to find trends.

References Odewahn, S. C. 1991, AJ, 101, 829. Acknowledgments Dr. Eric Wilcots

Dr. Bob Benjamin The first year grad student office (ok, ok, no pixels!)

Kiwi Davis and Adrienne Stilp the bug graveyard survivors the NSF

Recently Viewed Presentations

  • 18. Stoletje Barok - Rokoko

    18. Stoletje Barok - Rokoko

    18. stoletje - evropski visoki barok g. ph. telemann, j. j. fux, a. vivaldi evropski visoki barok Čas dinastiČnih vojn brez nacionalnih predznakov mednarodna druŽba aristokratov jezik francoski - glasba italijanska glasba po letu 1700 izoblikovanje skupnih pravil znaČilnost vseh...
  • The Four Basic Principles of Document Design

    The Four Basic Principles of Document Design

    Avoid elements that are merely similar. Proximity: Group related elements together GG Marquez 404.555.5555 Café Macando 100 Solidad Lane Bogota, Columbia Café Macando GG Marquez 100 Solidad Lane Bogota, Columbia 404.555.5555 Alignment: Every item should have a visual connection with...
  • Caught by the Tail: Tail Risk Neutrality and Hedge Fund Returns

    Caught by the Tail: Tail Risk Neutrality and Hedge Fund Returns

    Caught by the Tail: Tail Risk Neutrality and Hedge Fund Returns Stephen J. Brown Jonathan F. Spitzer NYU Stern Caught by the tail Historical perspective The myth of market neutrality Robust measure of tail risk neutrality Application to TASS data...
  • Changes to MFPH Part A

    Changes to MFPH Part A

    New Marking Algorithm. The requirement to score no more than one bad fail across Paper I in order to pass the paper has been removed. The requirement to score . 20 or more in each of Paper IIA and Paper...
  • Why do financial institutions exist?

    Why do financial institutions exist?

    Basic facts about financial structure throughout the world. Indirect finance, which involves the activities of financial intermediaries, is many times more important than direct finance, in which businesses raise funds directly from lenders in financial markets.
  • stench - rcboe.org

    stench - rcboe.org

    uneasy. Synonym-uncomfortable, Antonym-calm, comfortable, unpleasant, nervous, worried. happy
  • Drag picture to placeholder or click icon to

    Drag picture to placeholder or click icon to

    What is meant by recycling, waste that can be recycled and the advantages of recycling. How to be more energy efficient and to conserve water. The ways consumers can contribute to sustainable and responsible living. Organisations involved in raising awareness...
  • EPIC 2.03 PG&E Smart Inverters Modeling Project

    EPIC 2.03 PG&E Smart Inverters Modeling Project

    DER Connection Screening Practice: Used in FERC-SGIP, NY SIR, CA Rule 21 and most states . Aim to screen out DER connections prone to ground-fault overvoltage (GFO) and to limit allowed connection types based on concerns for ground fault and...