Transcript UKIDSS DXS and SDSS-2dF LRG Surveys

SDSS-2dF LRG Survey
and the prospects for its
UKIDSS-DXS counterpart
Alastair Edge
and SDSS-2dF team
Kyoto 13th January 2004
LRG = Luminous Red Galaxy
• Luminous = Massive, most likely elliptical
• Red = old, evolved stellar population
These two properties make LRGs
excellent tracers of large scale
structure and of galaxy evolution
LRGs targeted in SDSS out to z=0.4
Kyoto 13th January 2004
SDSS-2dF LRG Survey
• Extension of SDSS program which is
limited by 45min SDSS exposures
• Approx 150 candidates per 2dF field
and with 4hrs exposures we reach i=19.5
• Colour selection gives >60% z>0. 5
• Got 8 PATT nights in 03A (plus 4
Directors nights in April), 8 in 03B and
another 8 in 04A plus 36 from ATAC
over next 4 semesters (04A to 05B).
Kyoto 13th January 2004
Results
• 10 clear nights of 24 with very variable
conditions!
• Observed 19 fields with a total of 2,500
galaxy spectra
• Redshifts to 0.79
Kyoto 13th January 2004
More Results
• OII is common
• E+A signatures seen in some objects
• Strong clustering is seen
Kyoto 13th January 2004
Next
• Request for 28 nights over next 3
semesters from PATT
• Aim to obtain 10,000+ galaxies z>0.45
• Determine LSS at z=0.5, power
spectrum, galaxy evolution limits, etc
• Link to UKIDSS LAS in first 2 years
• Co-add spectra to get stellar ‘ages’
• QSOs in same field (PI Shanks)
Kyoto 13th January 2004
Other future work
• 8m studies selected 2dF LRG galaxies
• AAOmega survey in z=0.6-1.0 range
• Clusters in SDSS-2dF make a potentially
complete sample for cluster evolution
Kyoto 13th January 2004
UKIDSS DXS
• Goal of mapping the Universe at z=1-2
• 35 sq.deg. to J=23 and K=21 (12.6sq.deg.
in 2yrs)
• SuprimeCam imaging (next talk!)
• 4 fields – XMM-LSS, Lockman Hole,
ELAIS-N1, SA22
• Clustering, clusters etc…. (see Tanaka)
• “Old” science goals….? Much still to do.
Kyoto 13th January 2004
Possible FMOS LRG Survey
• The UKIDSS DXS provides an ideal
dataset for a similar “red” galaxy
selection at z>1.
• The optical/NIR selection will allow
reliable samples of ‘passive’ objects to
be identified (see Tamura tomorrow!)
• FMOS sensitivity will reach a similar
absolute magnitude range as the SDSS2dF sample.
Kyoto 13th January 2004
Conclusions
• The Universe at z<0.8 is accessible from a 4m
• Much more at z>1 will be reached by FMOS
• In future can study ‘old’ stellar populations
over 10Gyr
Kyoto 13th January 2004