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Rapture of the Deep Sky. Mel Ulmer Dept of Physics & Astronomy Northwestern University http://www.astro.northwestern.edu/~ulmer This talk posted on http://www.astro.northwestern.edu/~ulmer/private/coma/Rapture_of_the_Deep_sky.ppt Also need
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Rapture of the Deep Sky Mel Ulmer Dept of Physics & Astronomy Northwestern University http://www.astro.northwestern.edu/~ulmer This talk posted on http://www.astro.northwestern.edu/~ulmer/private/coma/Rapture_of_the_Deep_sky.ppt Also need http://www.astro.northwestern.edu/~ulmer/private/coma/mirror_comparison_lg.mov [quicktime] Also need http://www.astro.northwestern.edu/~ulmer/private/coma/lens0.mpeg [quicktime]
Age of Universe about 13.7 Gyr Clusters come into existence?
M h2 h2
P(k) Complementary measure crucial; Improves w and dw/dz by ~ factor 4 [h Mpc –1] P(k) [h –3 Mpc 3] k[h Mpc –1]
RCS1325+2858 z=0.95 Smoothed X-ray emission contours 2.5 arcmin/1.1 Mpc
The Coma Cluster • Rich cluster • Relatively close by: distance = 95 Mpc redshift = 0.02 • High galactic latitude: Ra = 12h 59m 48s Dec = 27d 58.8m NGC 4889 NGC 4874 10’ NGC 4911 280 kpc
300 kpc Coma Cluster X-ray residuals
Color-Magnitude Relation From R= 18! Many of our LSBs fall on the CMR! => Same origin and aging as larger galaxies
The CMR and LSBs Evolution • CMR is a metallicity effect: elliptical galaxies undergo extended star formation at high redshifts creating the CMR and then evolve passively • LSBs along the CMR sequence were formed at the same time as bright ellipticals and evovled in the same fashion 4874 4889 • Consistent with cluster formation simulations: first galaxies created are in the center (CMR LSBs) Contours of CMR LSBs 4911
Residual from X-rays after isothermal sphere fit subtracted Blue LSBs All LSBs Blue LSBs
Cl 1257+47 left color, visble=> near IR; right X-ray plus near IR
Chandra X-ray Observatory Schematic of Grazing Incidence, X-ray Mirrors CXC
What a low temp detector (LTD) does for you vs a CCD CCD Energy resolution LTD Energy Resolution
Dream Machine: 3,000 sq cm 10 eV energy Resolution 1 degree FOV 10 arc sec angular resolution Sky coverage between 1,000 and 10,000 sq degrees yielding approximately 10,000 clusters === Focal Length approximately 3 meters, diameter less than 2 meters. => NO Shuttle Launch Required!
Competition: XMM (1,00 sq mc) 10 degrees “deep” (approximately 50ksec/pointing) contiguous, 200 degrees shallower (approximately 10 ksec/exposure) and discontinuous, CCD energy resolution average angular resolution approximately 20 arc seconds. Chandra collection area ~400 sq cm, 0.5 arc second angular resolution. Steradian coverage approximately the same as XMM.
Hero Dr. Mel: Untouched comic strip. Reminds us we live on 4-D surface in 5-D manifold