XRay Spectroscopy in Astrophysics Luigi Piro Istituto Astrofisica

X-Ray Spectroscopy in Astrophysics Luigi Piro Istituto Astrofisica Spaziale Fisica Cosmica, Roma INAF L. Piro : X-ray spectroscopy - Frascati 2009

Summary • X-ray spectroscopy, the present instrumentation (CCD, gratings) • Opening a new window in Cosmology and Extreme physics • Enabling technology: TES microcalorimeters • Future missions: Xenia, IXO L. Piro : X-ray spectroscopy - Frascati 2009 2

X-ray spectroscopy in Astrophysics Cryogenic microcalorimeters (T=100 m. K) with high spectral resolution open a new observational window in Astrophysics and Cosmology. Example of astrophysical plasma (107 K) observed with: * TES microcalorimeters (DE=2 e. V, IXO, Xenia, DIOS) *Si-base microcalorimeters (DE=6 -8 e. V: ASTRO-H) *CCD (DE=100 e. V: XMM) L. Piro : X-ray spectroscopy - Frascati 2009 3

Science Drivers • What are the fundamental physical laws of the Universe? – Matter under extreme conditions • How did the Universe originate and what is it made of? – The early Universe – The Universe taking shape – The evolving violent Universe L. Piro : X-ray spectroscopy - Frascati 2009 4

HOW ? Most of the baryon of the Universe are locked in large scale, low density structures visible only in X-rays High resolution spectroscopy and spatial resolution, wide field in emission Structure Formation z 10 1 GRB as cosmological beacons: fast reaction, high res. absorption spectroscopy 0 Stars Galaxies Clusters Filaments L. Piro : X-ray spectroscopy - Frascati 2009 Structure size 5

XENIA Cosmic chemical evolution of baryons Undergoing US Decadal Survey 2010 As Medium Size Mission International consortium of Institutes from US, Eu, Japan L. Piro : X-ray spectroscopy - Frascati 2009 6

XENIA: Mission and Payload HARI: High Angular Resolution Imager 1000 cm 2@1 ke. V 0. 3 -8 ke. V CCD Field=1. 4° ang. res=10” constant CRIS: Cryogenic Imaging Spectrometer 1000 cm 2@0. 5 ke. V 0. 1 -3 ke. V TES DE<2. 5 e. V Field=1. 0° ang. res=3’ • Low bkg: LEO equatorial • Autonomous fast pointing in 60 s • 2 tons • TRL 4 • Decadal Survey • medium size TED: Transient Event Detector ¼ of the sky, 3’ localization 8 -200 ke. V L. Piro : X-ray spectroscopy - Frascati 2009 7

Tomography of the Universe: the Xray forest from the Cosmic Web with GRBs From 150 GRBs with afterglow Fluence>2 10 -6 cgs ~200 s OVII-OVIII filaments in 5 years L. Piro : X-ray spectroscopy - Frascati 2009 8

3 D mapping of the Cosmic Web Detected, OVII+OVIII in emission, 5 s, 1 Ms 4°x 4° Model, Dz=0. 01 Down to overdensities of 100 L. Piro : X-ray spectroscopy - Frascati 2009 9

GB 090423: z=8. 2 ! GRBs as cosmological probes • About 90% have a X-ray afterglow, 20 -40% are dark • High z events are dark (Lya forest absorption at z>6) • X-ray redshift • Observing a mid-bright GRB afterglow with a fast (min. ) pointing XENIA yields 106 X-ray photons, and 103 cts in 1 e. V resolution bin • Out of 400 =>Golden sample of >250 afterglows with high res. X-ray spectra: redshift, metals in host-galaxy and close L. Piro : X-ray spectroscopy - Frascati 2009 10

Narrow abs lines from ISM in our own host galaxy • Bright galactic binary (1820 -303) observed with Chandra grating (Yao and Wand 2006) L. Piro : X-ray spectroscopy - Frascati 2009 11

Metal and ISM evolution with GRB Metal enrichment in the environment of massive stars upto z>6 ISM of the host galaxy, kinematical studies of the outflows Resonant absorption lines X-ray metal edges from a from GRB host galaxy at z=1 GRB nearby environment at z=7 L. Piro : X-ray spectroscopy - Frascati 2009 12

IXO International X-ray Observatory Undergoing Dedadal Survey 2010 and ESA Cosmic Vision As Large Mission International consortium of Institutes from US, Eu, Japan L. Piro : X-ray spectroscopy - Frascati 2009 13

IXO Deployable Metering Structure w/Shroud Flight Mirror Assembly X-ray Microcalorimeter Spectrometer Spacecraft Bus Module - Wide Field X-ray Imager - Hard X-ray Imager - X-ray Grating Spectrometer - High Time Resolution - X-ray Polarimeter § 5 year life; 10 years on consumables L. Piro : X-ray spectroscopy - Frascati 2009 Atlas V 551 Medium Composite Fairing 14

Comparing IXO to Existing Missions The improvement of IXO relative to current X-ray missions is equivalent to a transition from the 200 inch Palomar telescope to a 20 m telescope, and at the same time shifting from spectral band imaging to an integral field spectrograph L. Piro : X-ray spectroscopy - Frascati 2009 15

Science Drivers 1) Matter under extreme conditions: • • • Supermassive Black Hole Growth Matter Orbiting a Black Hole Neutron Star Equation of State 2) Formation of Structures: • • • Nature of Dark Matter and Dark Energy Cosmic Feedback Missing Baryons 3) Observatory Science (Life Cycles of matter and energy) • • Origin and Dispersion of Elements Particel Acceleration Planet Formation Stellar Magnetic Fields L. Piro : X-ray spectroscopy - Frascati 2009 16

Black Hole Spin & Growth Non-spinning Rapidly-spinning IXO will measure relativistically-broadened iron line emission, measuring the black hole’s spin. L. Piro : X-ray spectroscopy - Frascati 2009 17

Determining M, R separately IXO XMS spectrum of x-ray burst Slowly rotating (45 Hz), 1. 4 M neutron star Fe XXVI Ha for z. GR = 0. 35 – determines M/R Doppler shifts cause line splitting – width depends on R 120 s exposure for 1 Crab burst L. Piro : X-ray spectroscopy - Frascati 2009 18

Neutron Star Equation of State Lattimer & Prakash 2007 L. Piro : X-ray spectroscopy - Frascati 2009 19

TES microcalorimeter L. Piro : X-ray spectroscopy - Frascati 2009 20

Manufacturing and testing TES on silicon membrane with Pulsed Laser deposition +deep RIE - Ir/Au, Ti/Au or Mo/Au (total thickness about 100 nm) onto Si. N (1 um) suspended membrane - Absorber (Au, Au/Bi, Cu/Bi, Sn, few um thick) growth on the TES substrate - Pixel about 250 x 250 um • Cryo system based on liquid-free Pulse –tube + ADR down to 50 mm (as in-flight) L. Piro : X-ray spectroscopy - Frascati 2009 Manufacturin g facility at INFN Genova Cryo testing facility at IASF-Roma 21

Detector Sizes and Single Pixel results EFWHM = 3. 6 e. V INFN and Genova Univ. Ferrari, Gatti et al. INFN and Genova Univ. TMU-ISAS SRON Hoevers et al. , J Low Temp Phys, 151, (2008) Akamatsu, LTD 13, in press, (2009) L. Piro : X-ray spectroscopy - Frascati 2009 Bandler et al. , J Low Temp Phys, 151, (2008) 22

TES microcalorimeter as flight instrument • Goal: kpixel array with 2 e. V resolution • Italy: consortium led by IASF-RM/INAF and INFN/Univ. Genova, IFN-RM/CNR, INAFPa, TAS-Mi • Co-Piship for IXO instrument in International Consortium with SRON, Goddard/NASA, JAXA L. Piro : X-ray spectroscopy - Frascati 2009 23

TES Arrays Multiplexing technique is necessary to minimize the heat load caused by thermal conduction through the harness to the cold finger (thousand wires). The array is powered and read by rows or by columns using different Multiplexing methods: 32 x 32 NASA GSFC – IXO/XMS • FDM (sinusoidal excitation) (bond pads for 256 channels only) • TDM (switch ON/OFF line by line) • CDM (inversion bias polarity) FDM technique: • Pixels are AC-biased (line by line) • Summing node (column by column) • De-modulation by the same frequency to recover the pulse Eckart, Doriese, SPIE Newsroom , 2009 L. Piro : X-ray spectroscopy - Frascati 2009 24

Summary • Future X-ray missions (IXO, Xenia) based on new generation of Transition Edge Sensor microcalorimeters (<2 e. V resolution, high count rate capabilities, imaging) enabling spatially resolved high spectral resolution • Fundamental issues addressing cosmology in Xrays and extreme physics L. Piro : X-ray spectroscopy - Frascati 2009 25