Orion Nebula
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Black holes,Galactic Dark Center Matter andGalactic Center Dark Energy: Measuring the Invisible with X-Ray Telescopes Christine Jones BeforeBefore 19301930 ---- only only opticaloptical observationsobservationsIntro ofof thethe skysky EarlyEarly 19301930’’s,s, KarlKarl JanskyJansky (Bell (Bell Labs)Labs) discovereddiscovered radioradio emissionemission fromfrom centralcentral regionregion ofof MilkyMilky WayWay 19491949 -- Herb Herb FriedmanFriedman ledled NRLNRL teamteam thatthat detecteddetected X-rayX-ray emissionemission fromfrom thethe SunSun (Geiger(Geiger counterscounters onon GermanGerman V-2V-2 rocket)rocket) 19621962 -- Riccardo Riccardo Giacconi Giacconi led led AS&EAS&E teamteam thatthat discovereddiscovered firstfirst non-solarnon-solar X-rayX-ray sourcesource (Sco(Sco X-1) X-1) andand X-rayX-ray backgroundbackground X-rays are absorbed by the Earth’s atmosphere X-ray astronomy requires access to space 19651965 -- Giacconi Giacconi et et al.al. observedobserved hohott spotsspots onon thethe sunsun withwith firstfirst imagingimaging X-rayX-ray telescopetelescope onon rocketrocketIntro (about(about thethe samesame diameterdiameter andand lengthlength asas GalileoGalileo’’ss 16101610 telescope)telescope) FromFrom GalileoGalileo’’ss telescopetelescope toto HSTHST ---- In In 400400 years,years, opticaloptical telescopetelescope sensitivitysensitivity hashas improvedimproved 100,000,000100,000,000 timestimes FromFrom GiacconiGiacconi’’ss first first rocketrocket toto ChandraChandra ---- In In ~40~40 years,years, X-rayX-ray telescopetelescope sensitivitysensitivity hashas comparablecomparable improvementimprovement Cut-away view of Chandra’s telescope with nested mirror segments Grazin g Mirror Polish, Fabrication Polishing a CXO Mirror Shell CXO Mirror Fabrication 19731973 -- 1974 1974 FirstFirst orbitingorbiting telescopetelescope onon SkylabSkylab 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 19781978 -- 1981 1981 EinsteinEinstein observatoryobservatory 19901990 -- 1999 1999 ROSATROSAT Intro First high resolution X-ray imaging and spectroscopy of galactic and German, US, and UK mission. extragalactic sources. All-sky survey Discovery of X-ray jets, hot gas in Resolved most of X-ray bkgd galaxies, X-ray binaries in other galaxies SpatialSpatial ResolutionResolution matters!matters! Intro Arcminute ROSAT image Few arcsecond ROSAT Cygnus Loop -- Rocket image with several arcminute resolution SpatialSpatial resolutionresolution matters!matters! CygnusCygnus looploop Intro Arcminute ROSAT image Few arcsecond ROSAT Chandra in Shuttle Cargo Bay C a r g o B a y Chandra X-Ray Observatory Launch July 1999 L a u n c h Chandra X-Ray Observatory released from shuttle D ep lo y Cassiopeia A Cas A Supernova Remnant - youngest in Milky Way First Light Chandra 1 Ms 1” resolution Supernova Remnant Cas A A, Spectrum See distribution of heavy elements in remnant Orion Nebula Orion nebulaROSAT (star forming region) with ROSAT Orion NebulXXXXXXXXXXXXXXXXXXXXXXa Orion Nebula with Chandra Chandra Orion Nebula 1’ ROSAT 1” Chandra Chandra Spatial resolution matters for star clusters CCCHANDRAHANDRA DDDEEPEEP FFFIELDIELD NNNORTHORTH Brandt, Garmire et al. 2003 Resolving the X-ray background into sources Black holes,Galactic Dark Center Matter andGalactic Center Dark Energy: Measuring the Invisible with X-Ray Telescopes 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 (108) gas. Would spatial resolution matter for clusters of galaxies? Isointensity contours from the Einstein Imaging Proportional Counter (IPC) superposed on optical sky survey photographs. 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) Clusters of galaxies are the largest collapsed structures Einstein in the Universe. arcminute Most of the mass in resolution clusters of galaxies is dark matter. Most of the luminous baryons are hot (108) gas. Would spatial resolution matter for clusters of galaxies? YES ! Chandra arcsecond resolution Perseus cluster (Fabian et al 2005) 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 M87- Chandra SMBH Jet Filaments X-ray cavities Forman et al. 2005, 2007 Buoyant Plasma Bubbles Inflated by AGN QuickTime™ and a Cinepak decompressor QuickTime™ and a are needed to see this picture. Cinepak decompressor g are needed to see this picture. Courtesy youtube M87 Churazov et al. 2001 Classic Shock in M87 Gas Pressure (3.5-7.5 keV) Gas Density (1.2-2.5keV) WHEN BUBBLES INFLATE THEY DRIVE SHOCKS “SEE” the Shock Central Piston = radio cocoon for 3.5-7.5 keV, brightness IS pressure Dark Matter and Cluster Mergers Pre-merger merger relaxed – The most energetic events since the Big Bang 15 63-64 –Two 10 Msun clusters have KE ~10 ergs 1E0657-56 (The Bullet Cluster) • Vital Statistics – z=0.30 (3.35 Gyr ago, or 1.2 Gpc away) – Supersonic merger Markevitch et al. – In plane of sky (+/-15 degrees) Clowe et al. 2006 – Speed ~ Mach 3 (4500 km/s) –Tbullet ~ 6-7 keV 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 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) Constraining cosmological models (dark energy) with clusters z < 0.1 z > 0.45 Vikhlinin et al 2009 Measuring Acceleration • Two measurements of Λ>0 without additional priors Formally, Λ>0 at 5σ –SN Ia using Mgas or MY proxies (no priors) – X-ray Cluster Growth 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 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 Black holes,Galactic Dark Center Matter andGalactic 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 Swift Redshift ~8.5 Gamma Ray Burst GRB 090423 “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 Blank Slide.