The Ubiquity of Stellar Halos In the Virgo Cluster Kevin McKinnon - - PowerPoint PPT Presentation

▶

Mar 27, 2023 100 likes •167 views

The Ubiquity of Stellar Halos In the Virgo Cluster Kevin McKinnon 1,2 Collaborators: Stphane Courteau 2 , Raja Guha Thakurta 1 1: University of California, Santa Cruz 2: Queens University Motivation Previously hard to observe (~27 mag

SLIDE 1

The Ubiquity of Stellar Halos In the Virgo Cluster

Kevin McKinnon1,2 Collaborators: Stéphane Courteau2, Raja Guha Thakurta1

1: University of California, Santa Cruz 2: Queen’s University

SLIDE 2

Motivation

Previously hard to observe

(~27 mag arcsec-2)1

Act as temporal window
f the accretion history
Helps set constraints
n formation models

Kevin McKinnon - Heidelberg 2018 2 1Courteau et al. 2011 (Figure 8)

HALO (4%) Disk Bulge M31

SLIDE 3

Next Generation Virgo Survey (NGVS)1

CFHT/ Megacam
104 deg2 FOV
Limiting mag

g = 28.8 mag arcsec-2

415 VCC objects used
Isophotal analysis
f 2D image2
Extraction of 1D (azimuthally

averaged) surface brightness profile

Kevin McKinnon - Heidelberg 2018 3 1Ferrarese et al. 2012, 2Courteau 1995

~360 arcsec (20 Re)

Halo Domain

SLIDE 4

Profile Classification for Virgo (NGVS) Galaxies

Type I 45% Type II 20%

Kevin McKinnon - Heidelberg 2018 5

Type III 35%

1SHIVir: Roediger et al. 2012 (Table 1)

This Work: Previous1: 35% 34% 34%

exponential

SLIDE 5

Profile Decomposition (VCC0355)

Profile Components Cumulative Light Fractions

Kevin McKinnon - Heidelberg 2018 6

SLIDE 6

Halo Light Fractions (N=87)

General (expected) trend of increasing HLF with host galaxy mass (Purcell et al. 2008)
Might be seeing the mass regime where low mass galaxies begin to self-populate halo

Kevin McKinnon - Heidelberg 2018 7 M31: Courteau et al. 2011, MW: Carollo et al. 2010, VCC Structural Parameters: Ouellette et al. 2017