Dark Energy: Measuring the Invisible with X-Ray Telescopes

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Lilian Whitehead
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1 Black holes, Galactic Dark Center Matter and Galactic Center Dark Energy: Measuring the Invisible with X-Ray Telescopes Christine Jones

Before 1930 -- only optical observations of the sky Intro Before 1930 -- only optical observations of the sky Early 1930 s, Karl Jansky (Bell Labs) discovered radio emission from central region of

2 Before only optical observations of the sky Intro Before only optical observations of the sky Early 1930 s, Karl Jansky (Bell Labs) discovered radio emission from central region of Milky Way Herb Friedman led NRL team that detected X-ray emission from the Sun (Geiger counters on German V-2 rocket) Riccardo Giacconi led AS&E team that discovered first non-solar X-ray source (Sco X-1) and X-ray background X-rays are absorbed by the Earth s atmosphere X-ray astronomy requires access to space

3 Giacconi et al. observed hot spots on the sun with first imaging X-ray telescope on rocket Intro (about the same diameter and length as Galileo s 1610 telescope) From Galileo s telescope to HST -- In 400 years, optical telescope sensitivity has improved 100,000,000 times From Giacconi s first rocket to Chandra -- In ~40 years, X-ray telescope sensitivity has comparable improvement

4 Cut-away view of Chandra s telescope with nested mirror segments Grazin g

5 Mirror Polish, Fabrication Polishing a CXO Mirror Shell CXO Mirror Fabrication

1973-1974 First orbiting telescope on Skylab Intro Two X-ray

through 6 different filters; returned to ground for

6 First orbiting telescope on Skylab Intro Two X-ray telescopes 35,000 X-ray images of the Sun recorded on film through 6 different filters; returned to ground for processing NEED X-RAY DETECTORS! Coronal holes and X-ray bright points

1978-1981 Einstein observatory 1990-1999 ROSAT Intro First high

7 Einstein observatory ROSAT Intro First high resolution X-ray imaging and spectroscopy of galactic and extragalactic sources. Discovery of X-ray jets, hot gas in galaxies, X-ray binaries in other galaxies German, US, and UK mission. All-sky survey Resolved most of X-ray bkgd

8 Spatial Resolution matters! Intro Arcminute ROSAT image Few arcsecond ROSAT Cygnus Loop -- Rocket image with several arcminute resolution

9 Spatial resolution matters! Cygnus loop Intro Arcminute ROSAT image Few arcsecond ROSAT

10 Chandra in Shuttle Cargo Bay C a r g o B a y

11 Chandra X-Ray Observatory Launch July 1999 L a u n c h

12 Chandra X-Ray Observatory released from shuttle D ep lo y

13 Cassiopeia A Cas A Supernova Remnant - youngest in Milky Way First Light Chandra 1 Ms 1 resolution

14 Supernova Remnant Cas A A, Spectrum See distribution of heavy elements in remnant

15 Orion Nebula Orion nebula ROSAT (star forming region) with ROSAT

16 Orion NebulXXXXXXXXXXXXXXXXXXXXXXa Orion Nebula with Chandra Chandra

17 Orion Nebula 1 ROSAT 1 Chandra Chandra Spatial resolution matters for star clusters

18 CHANDRA DEEP FIELD NORTH Brandt, Garmire et al Resolving the X-ray background into sources

19 Black holes, Galactic Dark Center Matter and Galactic Center Dark Energy: Measuring the Invisible with X-Ray Telescopes

20 Clusters of galaxies are the largest collapsed structures in the Universe. Most of the mass in clusters of galaxies is dark matter. Most of the luminous baryons are hot (10 8 ) gas. Would spatial resolution matter for clusters of galaxies? Isointensity contours from the Einstein Imaging Proportional Counter (IPC) superposed on optical sky survey photographs.

21 Expected hot gas to be relatively smooth (most of the time) Hot gas seen ONLY in X-ray band - thermal bremsstrahlung + lines For clusters, ~10% of mass is hot gas (5x more than stellar mass)

Most of the luminous baryons are hot (10 8 ) gas.

22 Clusters of galaxies are the largest collapsed structures in the Universe. Most of the mass in clusters of galaxies is dark matter. Most of the luminous baryons are hot (10 8 ) gas. Would spatial resolution matter for clusters of galaxies? YES! Perseus cluster (Fabian et al 2005) Einstein arcminute resolution Chandra arcsecond resolution

Forman et al 2005, 2007 Gas provides a fossil record of mass ejections and energy

23 Measuring volume of X-ray cavities, determines energy of outburst from SMBH Measuring distance of cavities from nucleus, determines outburst age M87 Fabian et al 2003, 2005 Forman et al 2005, 2007 Gas provides a fossil record of mass ejections and energy outbursts Measure outbursts in cavities over cosmic times Hot Gas - key to capturing AGN ouput

24 M87- Chandra SMBH Jet Filaments Forman et al. 2005, 2007 X-ray cavities

25 Buoyant Plasma Bubbles Inflated by AGN g QuickTime and a Cinepak decompressor are needed to see this picture. QuickTime and a Cinepak decompressor are needed to see this picture. M87 Churazov et al Courtesy youtube

Classic Shock in M87 Gas Density (1.2-2.5keV) Gas Pressure (3.5-7.

26 Classic Shock in M87 Gas Density ( keV) Gas Pressure ( kev) WHEN BUBBLES INFLATE THEY DRIVE SHOCKS SEE the Shock Central Piston = radio cocoon for kev, brightness IS pressure

27 Dark Matter and Cluster Mergers Pre-merger merger relaxed The most energetic events since the Big Bang Two M sun clusters have KE ~ ergs

1E0657-56 (The Bullet Cluster) Vital Statistics z=0.30 (3.35 Gyr ago, or 1.

28 1E (The Bullet Cluster) Vital Statistics z=0.30 (3.35 Gyr ago, or 1.2 Gpc away) Supersonic merger In plane of sky (+/-15 degrees) Speed ~ Mach 3 (4500 km/s) T bullet ~ 6-7 kev Markevitch et al. Clowe et al. 2006

30 Dark matter vs Luminous matter Clowe et al. (2006) Bradac et al. (2006) Data: 500 ks Chandra Magellan + ESO + HST imaging Results: Offsets between gas and DM peaks for both main and subcluster No offset between galaxies and DM

31 Dark Matter Exists The Bullet Cluster - an object whose visible mass and center of gravity are spatially separated. But, nature of Dark Matter is still unknown Also does not prove that gravity is Newtonian Courtesy Sean Carroll (cosmicvariance.com)

32 Constraining cosmological models (dark energy) with clusters z < 0.1 z > 0.45 Vikhlinin et al 2009

33 Measuring Acceleration Two measurements of Λ>0 without additional priors SN Ia X-ray Cluster Growth Formally, Λ>0 at 5σ using Mgas or MY proxies (no priors)

34 Complementary Constraints from different methods 68% confidence for individual data sets CMB, SN Ia, BAO Cluster growth of structure comparable to WMAP, SN Ia X-ray alone gives w0=-1.14±0.21

effects of systematics (by a factor of 2 with clusters; ±0.08 to 0.04 in w0) w0=-0.991±0.045(stat)±0.

35 Complementary Constraints in a flat Universe Combination is most powerful Exploits links among the observations CMB/WMAP at z~1000 to growth of structure at z~0 see clusters +WMAP contour Combined set reduces effects of systematics (by a factor of 2 with clusters; ±0.08 to 0.04 in w0) w0=-0.991±0.045(stat)±0.039(sys) factor of 1.5 in stat and factor of 2 in sys (compared to without clusters) Looks like a cosmological constant/vacuum energy

36 Black holes, Galactic Dark Center Matter and Galactic Center Dark Energy: Measuring the Invisible with X-Ray Telescopes Measured output history of supermassive black holes Showed dark matter exits Constrained Dark Energy equation of state

37 Swift Redshift ~8.5 Gamma Ray Burst GRB a true blast from the past Highest redshift object known Explosion of massive star At the Galileo National Telescope, a team measured the redshift. A telescope named for Galileo made this measurement during the year in which we celebrate Galileo s first astronomical use of the telescope

38 Blank Slide

Part 2. Hot gas halos and SMBHs in optically faint ellipticals. Part 3. After Chandra?

Hot gas and AGN Feedback in Nearby Groups and Galaxies Part 1. Cool cores and outbursts from supermassive black holes in clusters, groups and normal galaxies Part 2. Hot gas halos and SMBHs in optically