uncovering%the%firstgalaxies%in% the%frontier%fields · 12november2014...

Yale  Hubble  Frontier  Fields  Workshop

Uncovering  the  First  Galaxies  in  the  Frontier  Fields

Rachael  Livermore  University  of  Texas  at  Austin

12  November  2014 1

Yale  Hubble  Frontier  Fields  Workshop

The  Problem:  It  is  difficult  to  detect  faint  sources  in  the  most  magnified  regions  of  cluster  fields

Ishigaki+  2014 Atek+  2014

12  November  2014 2

Yale  Hubble  Frontier  Fields  Workshop

The  Problem:  It  is  difficult  to  detect  faint  sources  in  the  most  magnified  regions  of  cluster  fields

Ishigaki+  2014 Atek+  2014

Critical  line  at  z=7  denotes  region  of  

maximum  magnification

12  November  2014 2

Yale  Hubble  Frontier  Fields  Workshop

The  Problem:  It  is  difficult  to  detect  faint  sources  in  the  most  magnified  regions  of  cluster  fields

Ishigaki+  2014 Atek+  2014

Critical  line  at  z=7  denotes  region  of  

maximum  magnification

High-­‐z  sources  concentrated  around  outskirts  of  cluster  where  magnification  

➔  1

12  November  2014 2

Yale  Hubble  Frontier  Fields  Workshop

The  highly  magnified  regions  represent  the  smallest  volume…

…and  the  bright  foreground  galaxies  and  intracluster  light  limit  the  depth  of  the  image  in  the  central  

regions

12  November  2014 3

Yale  Hubble  Frontier  Fields  Workshop

The  highly  magnified  regions  represent  the  smallest  volume…

…and  the  bright  foreground  galaxies  and  intracluster  light  limit  the  depth  of  the  image  in  the  central  

regions

12  November  2014 3

Yale  Hubble  Frontier  Fields  Workshop

The  highly  magnified  regions  represent  the  smallest  volume…

…and  the  bright  foreground  galaxies  and  intracluster  light  limit  the  depth  of  the  image  in  the  central  

regions

12  November  2014 3

Yale  Hubble  Frontier  Fields  Workshop12  November  2014 4

Wavelet  Decomposition

Yale  Hubble  Frontier  Fields  Workshop12  November  2014 4

Wavelet  Decomposition

Yale  Hubble  Frontier  Fields  Workshop12  November  2014 4

Wavelet  Decomposition

Yale  Hubble  Frontier  Fields  Workshop12  November  2014 4

Wavelet  Decomposition

Yale  Hubble  Frontier  Fields  Workshop12  November  2014 4

Wavelet  Decomposition

Yale  Hubble  Frontier  Fields  Workshop12  November  2014 4

Wavelet  Decomposition

Yale  Hubble  Frontier  Fields  Workshop12  November  2014 4

Wavelet  Decomposition

Yale  Hubble  Frontier  Fields  Workshop12  November  2014 4

Wavelet  Decomposition

Yale  Hubble  Frontier  Fields  Workshop12  November  2014 4

Wavelet  Decomposition

Yale  Hubble  Frontier  Fields  Workshop12  November  2014 4

Wavelet  Decomposition

Yale  Hubble  Frontier  Fields  Workshop12  November  2014 4

Wavelet  Decomposition

Yale  Hubble  Frontier  Fields  Workshop12  November  2014 5

Wavelet  Decomposition

Yale  Hubble  Frontier  Fields  Workshop12  November  2014 5

Wavelet  Decomposition

Yale  Hubble  Frontier  Fields  Workshop12  November  2014 5

Wavelet  Decomposition

Cluster  modelWavelet-­‐subtracted  image

Yale  Hubble  Frontier  Fields  Workshop12  November  2014 6

Removing  the  foreground  light  makes  it  easier  to  detect  small,  faint  objects  behind  the  cluster

Yale  Hubble  Frontier  Fields  Workshop12  November  2014 7

Simulations  show  we  recover  more  faint  sources  when  wavelet-­‐subtracted  images  

are  used  for  detection

Fake  source  input  magnitude

Fractio

n  of  so

urces  recovered

Original  (unsubtracted)  

image

Increasingly  aggressive  subtraction

Yale  Hubble  Frontier  Fields  Workshop12  November  2014 7

Simulations  show  we  recover  more  faint  sources  when  wavelet-­‐subtracted  images  

are  used  for  detection

Fake  source  input  magnitude

Fractio

n  of  so

urces  recovered

Original  (unsubtracted)  

image

Increasingly  aggressive  subtraction

Bright  sources  are  lost  in  the  subtraction,  but  

fainter  sources  become  easier  to  recover

Yale  Hubble  Frontier  Fields  Workshop12  November  2014 8

Wavelet  subtraction  improves  depth  across  the  field,  particularly  the  crucial  

central  region

Original  image

Yale  Hubble  Frontier  Fields  Workshop12  November  2014 8

Wavelet  subtraction  improves  depth  across  the  field,  particularly  the  crucial  

central  region

Original  image Subtraction  scale  0

Yale  Hubble  Frontier  Fields  Workshop12  November  2014 8

Wavelet  subtraction  improves  depth  across  the  field,  particularly  the  crucial  

central  region

Original  image Subtraction  scale  1

Yale  Hubble  Frontier  Fields  Workshop12  November  2014 8

Wavelet  subtraction  improves  depth  across  the  field,  particularly  the  crucial  

central  region

Original  image Subtraction  scale  2

Yale  Hubble  Frontier  Fields  Workshop12  November  2014 8

Wavelet  subtraction  improves  depth  across  the  field,  particularly  the  crucial  

central  region

Original  image Subtraction  scale  3

Yale  Hubble  Frontier  Fields  Workshop12  November  2014 8

Wavelet  subtraction  improves  depth  across  the  field,  particularly  the  crucial  

central  region

Original  image Subtraction  scale  4

Yale  Hubble  Frontier  Fields  Workshop12  November  2014 8

Wavelet  subtraction  improves  depth  across  the  field,  particularly  the  crucial  

central  region

Original  image Subtraction  scale  5

Yale  Hubble  Frontier  Fields  Workshop12  November  2014 9

Up  to  scale  5,  flux  recovery  remains  robust  if  the  original  image  is  used  for  

photometry

Fake  source  input  magnitude

Inpu

t  –  Recovered

 magnitude

Yale  Hubble  Frontier  Fields  Workshop

Candidate  selection  in  Abell  2744

12  November  2014 10

Yale  Hubble  Frontier  Fields  Workshop

z  ~  7

Candidate  selection  in  Abell  2744

12  November  2014 10

Yale  Hubble  Frontier  Fields  Workshop

z  ~  7z  ~  8

Candidate  selection  in  Abell  2744

12  November  2014 10

Yale  Hubble  Frontier  Fields  Workshop

z  ~  7z  ~  8z  ~  9

Candidate  selection  in  Abell  2744

12  November  2014 10

Yale  Hubble  Frontier  Fields  Workshop

z  ~  7z  ~  8z  ~  9

Candidate  selection  in  Abell  2744

12  November  2014 10

We  find  53  galaxies  at  z  ≥  7:  34  at  z  ≈  7  16  at  z  ≈  8  3  at  z  ≈  9

Yale  Hubble  Frontier  Fields  Workshop

Candidate  selection  in  MACS0416

12  November  2014 11

Yale  Hubble  Frontier  Fields  Workshop

z  ~  7

Candidate  selection  in  MACS0416

12  November  2014 11

Yale  Hubble  Frontier  Fields  Workshop

z  ~  7z  ~  8

Candidate  selection  in  MACS0416

12  November  2014 11

Yale  Hubble  Frontier  Fields  Workshop

z  ~  7z  ~  8z  ~  9

Candidate  selection  in  MACS0416

12  November  2014 11

Yale  Hubble  Frontier  Fields  Workshop

z  ~  7z  ~  8z  ~  9

Candidate  selection  in  MACS0416

12  November  2014 11

We  find  23  galaxies  at  z  ≥  7:  7  at  z  ≈  7  8  at  z  ≈  8  8  at  z  ≈  9

Yale  Hubble  Frontier  Fields  Workshop

Observed  number  counts  at  z  ≥  7

z  ≈  7

Observed  mag

n

z  ≈  8 z  ≈  9

12  November  2014 12

Yale  Hubble  Frontier  Fields  Workshop

Observed  number  counts  at  z  ≥  7

z  ≈  7

Observed  mag

n

z  ≈  8 z  ≈  9

12  November  2014 12

Yale  Hubble  Frontier  Fields  Workshop

Observed  number  counts  at  z  ≥  7

z  ≈  7

Observed  mag

n

z  ≈  8 z  ≈  9

12  November  2014 12

Yale  Hubble  Frontier  Fields  Workshop

Observed  number  counts  at  z  ≥  7

z  ≈  7

Observed  mag

n

z  ≈  8 z  ≈  9

12  November  2014 12

Wavelet  subtraction  enables  us  to  detect  more  faint  

galaxies

Yale  Hubble  Frontier  Fields  Workshop

Observed  magnitudes  of  z>7  candidates

12  November  2014 13

Abell  2744 MACS  0416

H-­‐band  mag  (observed)H-­‐band  mag  (observed)

n n

z  ~  7z  ~  8z  ~  9

Yale  Hubble  Frontier  Fields  Workshop

Observed  magnitudes  of  z>7  candidates

12  November  2014 13

Abell  2744 MACS  0416

H-­‐band  mag  (observed)H-­‐band  mag  (observed)

n n

z  ~  7z  ~  8z  ~  9

Yale  Hubble  Frontier  Fields  Workshop

Observed  magnitudes  of  z>7  candidates

12  November  2014 13

Abell  2744 MACS  0416

H-­‐band  mag  (observed)H-­‐band  mag  (observed)

n n

z  ~  7z  ~  8z  ~  9

Yale  Hubble  Frontier  Fields  Workshop

Magnification

12  November  2014 14

Yale  Hubble  Frontier  Fields  Workshop

Magnification

12  November  2014 14

Yale  Hubble  Frontier  Fields  Workshop

Magnification

12  November  2014 14

CATS

Yale  Hubble  Frontier  Fields  Workshop

Magnification

12  November  2014 14

Bradac

Yale  Hubble  Frontier  Fields  Workshop

Magnification

12  November  2014 14

Merten

Yale  Hubble  Frontier  Fields  Workshop

Magnification

12  November  2014 14

Sharon

Yale  Hubble  Frontier  Fields  Workshop

Magnification

12  November  2014 14

Williams

Yale  Hubble  Frontier  Fields  Workshop

Magnification

12  November  2014 14

Zitrin-­‐LTM

Yale  Hubble  Frontier  Fields  Workshop

Magnification

12  November  2014 14

Zitrin-­‐NFW

Yale  Hubble  Frontier  Fields  Workshop

Magnification

12  November  2014 14

Zitrin-­‐NFW

The  photo-­‐z  is  the  dominant  source  of  error  on  the  

magnification,  but  model  uncertainties  are  important  at  

high  magnification

Yale  Hubble  Frontier  Fields  Workshop

Intrinsic  magnitudes  of  z  ≥  7  candidates

12  November  2014 15

Abell  2744 MACS  0416

H-­‐band  mag  (intrinsic)H-­‐band  mag  (intrinsic)

n n

Yale  Hubble  Frontier  Fields  Workshop

Intrinsic  magnitudes  of  z  ≥  7  candidates

12  November  2014 15

Abell  2744 MACS  0416

H-­‐band  mag  (intrinsic)H-­‐band  mag  (intrinsic)

n n

Yale  Hubble  Frontier  Fields  Workshop

Intrinsic  magnitudes  of  z  ≥  7  candidates

12  November  2014 15

Abell  2744 MACS  0416

H-­‐band  mag  (intrinsic)H-­‐band  mag  (intrinsic)

n n

Yale  Hubble  Frontier  Fields  Workshop

Summary

• We  are  using  wavelet  decomposition  to  remove  foreground  cluster  light  

!• We  find  this  increases  the  depth  of  the  image  without  impacting  the  

photometry  !• Early  results  indicate  78  lensed  z  ≥  7  galaxies  in  the  first  two  clusters

12  November  2014 16