Download Discovery of Cluster-Scale Lensed Quasars using the Subaru

Discovery of Cluster-Scale
Lensed Quasars using the
Subaru Telescope
Naohisa Inada （RIKEN）
M.Oguri, T.Broadhurst, E.Falco et al.
Subaru Users’ Meeting
29－31 Jan. 2008 @NAOJ
# OUTLINE #
We are carrying out the Sloan Digital Sky Survey
Quasar Lens Search （SQLS）. The main purposes of
the SQLS are 1） constructing a large statistical sample
of lensed quasars and 2） searching quasars lensed by
clusters of galaxies, i.e., a new population of lensed
quasars. So far we have succeeded in discovering two
cluster-scale lensed quasars, SDSS J1004+4112 and
SDSS J1029+2623. We used the Subaru Telescope
for the discoveries and further follow-up observations
of both of them.
Introduction
Overview of the SQLS :
Gravitationally lensed quasar survey using the SDSS
data. ~50 new lensed quasars are expected to be
discovered from the ~100,000 SDSS quasars.
Main Purposes :
1） Constructing a largest statistical sample of lensed
quasars to probe dark energy.
２） Discovering cluster-scale lensed quasars to probe
dark matter in galaxy clusters.
Current Status :
We have succeeded in discovering 28 lensed quasars
so far, including 2 cluster-scale lensed quasars. We
have completed the first statistical sample from DR3.
Discovery of SDSS J1004+4112
SDSS J1004+4112 :
The first （1/2） cluster-scale lensed quasar.
 = 14.6", zsource = 1.734, zlens = 0.680
D
B
A
C
gri-band
Subaru Suprime-Cam
Keck LRIS
existence of the lensing
galaxy cluster
originate a single
source quasar
Discovery of SDSS J1029+2623
SDSS J1029+2623 :
The second （2/2） cluster-scale lensed quasar.
 = 22.3", zsource = 2.197, zlens = 0.600
B
A
Subaru FOCAS
existence of
lensing galaxy
cluster
VLA
originate a single
source quasar
Central lensed image of SDSS J1004+4112
E
D
B
A
E
C
HST ACS
spectroscopically confirmed
central odd lensed image!!
（NFW +ρ   < 2.0）
FOCAS
C
Arcs in the SDSS J1029+2623 field
FOCAS
Many arcs are found
in the J1029 field
We are going to
propose service obs
for deeper images.
FOCAS
V between G1 and G2
is more than 2000 km/s
ongoing merger of
two clusters!?
Summary
• We discovered two cluster-scale lensed quasars,
SDSS J1004+4112 and SDSS J1029+2623 using
the Subaru Telescope.
• Further follow-up observations with Subaru :
We spectroscopically confirmed the central lensed
image of J1004, and we may find J1029 to be more
interesting （important） than J1004.
# References #
J1004 discovery : Inada et al. 2003, Nature, 426, 810 ; Oguri et al. 2004, ApJ, 605, 78
J1029 discovery : Inada et al. 2006, ApJ, L97
J1004 central image : Inada et al. 2005, PASJ, 57, L7 ; Inada et al. in preparation
J1029 follow-up : Oguri et al. ApJL submitted