Weak%20lensing%20mass-selected%20cluster%20catalogues

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Weak lensing mass-selected cluster catalogues
Weak lensing mass maps from the HST COSMOS survey
Richard Massey (CalTech) with Justin
Albert (CalTech), Joel Bergé (Saclay), Richard
Ellis (CalTech), Alexis Finogeunov (Garching),
Luigi Guzzo (INAF), Catherine Heymans (UBC),
Jean-Paul Kneib (Marseille), Alexie Leauthaud
(Marseille), Alexandre Refregier (Saclay), Jason
Rhodes (JPL), Nick Scoville (CalTech), James
Taylor (CalTech), Ludovic Van Waerbeke (UBC) and
the COSMOS team
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COSMOSCosmic Evolution Survey

• Largest ever HST survey
• 587 contiguous ACS fields
• 2 square degrees
• VSDSS at z1
• Depth IF814lt26.6 (at 5?)
• 2 million galaxies
• 80 resolved galaxies/arcmin2

Public data! http//irsa.ipac.caltech.edu/Missions
/cosmos.html
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Multiwavelength follow-up
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COSMOS team members
Nick Scoville (PI) Roberto Abraham Masaru
Ajiki Justin Alpert Herve Aussel Josh
Barnes Andrew Blain Daniela Calzetti Peter
Capak John Carlstrom Chris Carilli Andrea
Cimatti Andrea Comastri Marcella Corollo Emannuel
Daddi Richard Ellis Martin Elvis Amr El
Zant Shawn Ewald Mike Fall Alexis
Finoguenov AlbertoFranceschini Mauro Giavalisco
Richard Griffiths Gigi Guzzo Gunther
Hasinger Chris Impey Jean-Paul Kneib Karel
Nel Jeyhan Kartaltepe Jin Koda Anton
Koekemoer Lisa Kewley Alexie Leauthaud Olivier
LeFevre Ingo Lehmann Simon Lilly Thorsten
Lisker Charles Liu Richard Massey Henry
McCracken Yannick Mellier Satoshi Miyazaki Bahram
Mobasher Takashi Murayama Colin Norman
Alexandre Refregier Alvio Renzini Jason
Rhodes Mike Rich Dimitra Rigopoulou Dave
Sanders Shunji Sasaki Dave Schminovich Eva
Schinnerer Marco Scodeggio Kartik Sheth Patrick
Shopbell Jason Surace Yoshi Taniguchi James
Taylor Dave Thompson Neil Tyson Meg Urry Ludovic
Van Waerbeke Paolo Vettolani Simon White Lin Yan
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Issues from space - to bear in mind for DUNE,
SNAP,

• ACS pixels are slightly undersampled.
• PSF is not stable even from space - HST
  breathes.
• Charge transfer (in)efficiency in CCDs that have
  been
• degraded by cosmic rays.
• 8 band photo-zs are not yet totally reliable.
• 10 additional bands to be observed during 2006.

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Strong Gravitational Lensing
A gravitational field distorts all of space-time
like a rubber sheet. Even light rays bend around
the massive cores of galaxy clusters. The image
of a background galaxy can be strongly lensed
into multiple sources (corresponding to multiple
paths around the lens) and distorted into
arcs. Gravitational lensing is geometric. It
occurs regardless of the nature and state of the
foreground mass, and can thus be a bias-free
probe of dark matter!
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Weak Gravitational Lensing
The measurement of weak gravitational lensing
relies on the fact that averaging the shapes of
100 distant galaxies produces a circle.
zgalaxy1
zobserver0
Light actually follows the distorted path
(exaggerated) through intervening large-scale
structure. Adjacent background galaxies are
coherently distorted into an ellipse. Like glass
lenses, gravitational lenses are most effective
when placed half way between the source and the
observer.
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Weak gravitational lensingpatterns in a shear
field
Clusters are patterns in a shear field
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The usual cosmic shear analysisshear-shear
correlation functions
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(Photometric) redshift tomography
zgt1.5
1.1ltzlt1.5
0.8ltzlt1.1
0.4ltzlt0.8
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PRELIMINARY!Cosmological parameter constraints
?8
-3.0 -2.5 -2.0 -1.5
-1.0 -0.5 0.0
w
w
?m
Courtesy Joel Bergé
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Mass map of COSMOS survey
Sorry - this image is not yet publicly available
Using wavelet reconstruction method of Starck et
al. (2006) See poster by Sandrine Pires
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Residual systematics (B modes)
Sorry - this image is not yet publicly available
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Lensing sensitivity with redshift
Number of resolved galaxies
z
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Mass vs light
Sorry - this image is not yet publicly available
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Mass vs x-rays
Sorry - this image is not yet publicly available
Gunther Hasinger, Alexis Finoguenov Nico
Cappelluti
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Mass vs x-rays
Courtesy Alexis Finoguenov
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Zoom to one cluster at z0.73
Guzzo et al. (2006)
Lensing
X-ray
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Lensing sensitivity function (split)
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Lensing sensitivity function(tomography)
Number of resolved galaxies
z
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Tomography (3D maps)
Sorry - this image is not yet publicly available
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Tomography (3D maps)
Sorry - this image is not yet publicly available
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Tomography (3D maps)
Sorry - this image is not yet publicly available
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PRELIMINARY!Completely 3D maps
This was displayed via IDL Even powerpoint isnt
that good!
Courtesy David Bacon
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Conclusions

• COSMOS is the largest ever HST survey, sampling a
  complete range of large-scale structure and
  environments.
• Public data http//irsa.ipac.caltech.edu/Missions/
  cosmos.html
• Tomographic weak lensing analysis constrains ?m,
  ?8 and w.
• Reconstructed mass maps provide a direct view of
  the filamentary dark matter distribution with
  unprecedented resolution.
• Maps can be made fully 3D.
• Optimally-tuned lensing analysis around
  identified structures links into astrophysics (MD
  relation, x-ray MT, cluster formation)