Presentation on theme: "UCL’s interests: photo-z, mass-obs calibration, systematics Granada, Sep 2010 Ofer Lahav, University College London Ofer Lahav, Stephanie Jouvel, Ole Host."— Presentation transcript:
UCL’s interests: photo-z, mass-obs calibration, systematics Granada, Sep 2010 Ofer Lahav, University College London Ofer Lahav, Stephanie Jouvel, Ole Host University College London
Problems for LCDM on the ‘small scales’ The MW satellites – too many in simulations? Cluster mass profiles – concentration too low in simulations? Hierachical clustering – the wrong order? Galaxies in voids- too many in simulations? Superclusters – too few in simulatons? Are we near a centre of a void?
Photometric and Spectroscopic surveys 2010- 2020
The Dark Energy Survey (DES) Proposal: –Perform a 5000 sq. deg. survey of the southern galactic cap; –300 million galaxies –Measure dark energy with LSS, clusters, WL, SN New Instrument: –2.2 FOV, 520 Mega pixel optical CCD camera + corrector Time scale: –Instrument Construction 2008-2011 Survey: –525 nights during Oct.–Feb. 2011-2016 –Area overlap with SPT SZ survey and VISTA VHS Use the Blanco 4m Telescope at the Cerro Tololo Inter-American Observatory (CTIO)
From Tom Broadhurst’s talk Sample selection in Color-Color Red – background Blue – background Green – cluster +~background Pink – foreground +background A370
Sensitivity of Cosmology to photo-z methods Baryon Fraction Omega_matter Thomas, Abdalla & Lahav 2010
Photo-z challenges for CLASH Cluster, fg, bg membership with probabilities Try hybrid template + training methods Biases in input photometry due to blending and lensing Optimal filters for WL (4-5) and for SL (16) Spectroscopic training sets “Self calibration”, “colour tomography”, “SB prior”