The Future of Xray Astronomy Keith Arnaud NASAGSFC

The Future of X-ray Astronomy Keith Arnaud NASA/GSFC and UMCP X-ray Astronomy School 2002

Theme In the first 40 years of X-ray astronomy we increased sensitivity by a factor of 109, image resolution by 2. 5 x 105, spectral resolution by 104. How do we keep this progress up for the next 40 years ? • High sensitivity, high resolution spectroscopy. • Polarimetry • Interferometry X-ray Astronomy School 2002

Calorimetry About 150 years ago, James Joule and Julius von Mayer independently determined that HEAT = ENERGY, and calorimetry was born. But, only about 20 years ago, the power of performing calorimetric measurements at very low temperatures (< 0. 1 K) was realized, independently, by Harvey Moseley and by Etorre Fiorini and Tapio Niinikoski. This is called MICROCALORIMETRY, or occasionally QUANTUM CALORIMETRY, because of its ability to measure the energy of individual photons or particles with high sensitivity. X-ray Astronomy School 2002 Stahle

X-ray calorimetry X-ray Astronomy School 2002 Stahle

Microcalorimeters vs. Gratings • Resolutions comparable with gratings. Microcalorimeters win at high energies, gratings at low energies. • Non-dispersive so : o high efficiency o low background o no problems for extended sources o wide bandpass • However, microcalorimeters are cryogenic experiments requiring cooling to ~60 m. K. X-ray Astronomy School 2002

A Multiwavelength Note • Microcalorimeters were first developed for IR and are being used on IR astronomy space missions. • They are also being used on optical telescopes - where they provide filter type spectral resolution without using filters. • They are also used in laboratory dark matter searches. X-ray Astronomy School 2002

X-rays on Ice The XRS X-ray microcalorimeter built for Astro-E (the fifth Japanese X-ray astronomy satellite) Resolution : 9 - 12 e. V FWHM (0. 5 - 10 ke. V) X-ray Astronomy School 2002

Inserting the He dewar in the Ne dewar A solid Ne dewar outside a liquid He dewar outside an adiabatic demagnetization refrigerator. X-ray Astronomy School 2002

Ready for Launch from Kagoshima Space Center (KSC) February 2000

You need all the help you can get X-ray Astronomy School 2002

Astro-E Launch X-ray Astronomy School 2002

20 seconds and going well X-ray Astronomy School 2002

Uh - oh X-ray Astronomy School 2002

You really don’t want to see this Astro-E is being rebuilt as Astro-E 2 and will be launched in Jan/Feb 2005.

XRS on EBIT at LLNL X-ray Astronomy School 2002

Laboratory Astrophysics with a Microcalorimeter X-ray Astronomy School 2002

Constellation-X X-ray Astronomy School 2002

X-ray Astronomy School 2002

X-ray Astronomy School 2002

X-ray Astronomy School 2002

Constellation-X Overview o Use X-ray spectroscopy to observe § Black holes: strong gravity & evolution § Large scale structure in the Universe & trace the underlying dark matter § Production and recycling of the elements o Mission parameters § Telescope area: 3 m 2 at 1 ke. V 100 times XMM/Chandra for high res. spectra § Spectral resolving power: 300 -3, 000 5 times improvement at 6 ke. V § Band pass: 0. 25 to 40 ke. V 100 times more sensitive at 40 ke. V X-ray Astronomy School 2002

Counts per 0. 25 e. V bin 120 Calorimeter developement 100 80 Al Ka 1, 2 60 Instrument Resolution: 2. 0 0. 1 e. V FWHM 40 Al Ka 3, 4 20 0 1485 1490 1495 1500 Energy (e. V) 450 counts/sec 1505 Bismuth absorber TES Al/Ag bilayer X-ray Astronomy School 2002 K. Irwin

Goddard Mo/Au TES: 2. 4 +/- 0. 2 e. V at 1. 5 ke. V and 3. 7 +/- 0. 2 e. V at 3. 3 ke. V. K Ka into 500 x 500 micron TES Al Ka into 300 x 300 micron TES X-ray Astronomy School 2002

Mc. Kee-Taylor Decadal Survey “Constellation-x observatory is the premier instrument to probe the formation and evolution of black holes. . . The first clusters of galaxies. . . Quasars at high redshift. . . And the formation of the chemical elements…” “Constellation-x will complement Chandra, much as Keck and Gemini complement HST…” X-ray Astronomy School 2002

XEUS • ESA proposed mission for low Earth orbit. • 6 m 2 of collecting area at 1 ke. V. • Imaging resolution goal of 2" HEW (Half Energy Width) at 1 ke. V. • Limiting sensitivity 100 times deeper than XMM-NEWTON. • Spectral resolution of 1 to 10 e. V between 0. 05 and 30 ke. V. X-ray Astronomy School 2002

XEUS II • After completion of the initial 4 -6 year mission phase, XEUS will rendezvous with the ISS for refurbishment and adding extra mirror area. • New detector spacecraft with next generation of focal plane technologies. • Grown mirror will have 30 m 2 collecting area at 1 ke. V; 3 m 2 at 8 ke. V. • Sensitivity 250 times better than XMM-NEWTON. X-ray Astronomy School 2002

Con-x X-ray Astronomy School 2002

Generation X o Scientific goal: to probe the X-ray emission from the universe at z = 5 -10. o An effective area of 150 m 2 at 1 ke. V with an angular resolution of ~ 0. 1 arc second. o Detect sources 1000 times fainter than Chandra (flux limit of 2 x 10 -20 ergs/cm 2/s). o Obtain high resolution spectra from sources 100 -1000 x fainter than observable by Constellation-X. o Six identical satellites with 40 to 150 m focal length to L 2. X-ray Astronomy School 2002

Telescope Evolution No. Angu of lar mod HPD s Eff. Area @ 1 ke. V (cm 2 ) per mod. Mass (kg) per mod. Notes Chandra 1 0. 5" 1, 000 Ground and polished glass shells XMM-Newton 3 15" 1, 500 420 Replicated Ni shells Astro-E 5 90" 400 12 Replicated Al segments Constellation-X 4 15" 7, 500 420 Material and technology under study/development Generation-X 6 0. 1" 250, 000 3, 000 Materials and fabrication technology to be determined

Why X-ray Polarimetry ? • Because it’s there ! Whenever we look at the Universe in a new way we make unexpected discoveries. • We expect polarization from X-ray synchrotron sources such as SNR and jets. Also from X-ray reflection in binaries and AGN. • There is one detection of X-ray polarization - that of the Crab Nebula SNR. • No X-ray polarimeter has flown on a satellite since the 1970 s. • There is a new idea for a more efficient polarimeter… X-ray Astronomy School 2002

Polarization

Electron Tracks X-ray Astronomy School 2002 Bellazzini et al.

Microwell detector X-ray Astronomy School 2002 Bellazzini et al.

Bellazzini et al. X-ray Astronomy School 2002

Accumulation of many events 5. 9 Ke. V unpolarized X-ray Astronomy School 2002 5. 4 Ke. V polarized Bellazzini et al.

X-ray Interferometry • While astronomical sensitivity has increased by a vast factor imaging resolution has not. HST is only 100 times better than Galileo’s telescope. • To do better requires interferometry. • Radio interferometry is well developed but baselines are very long and few sources have high enough surface brightness in the radio band. • Optical interferometry is in the experimental stage and milliarcsec resolutions should be achievable. X-ray Astronomy School 2002

X-ray Interferometry II The X-ray band is the natural place for interferometry ! • Microarcsecond resolutions are possible with a baseline of ~10 meters. • X-ray sources have very high surface brightness on microarcsecond scales. X-ray interferometry allows virtual interstellar travel… X-ray Astronomy School 2002

100 milliarcseconds

10 milliarcseconds

1 milliarcsecond

100 microarcseconds

10 microarcseconds

1 microarcsecond

X-ray Astronomy School 2002

X-ray Astronomy School 2002

X-ray Astronomy School 2002

MAXIM Pathfinder Milliarcsecond resolution

Timeline 2002 (Integral) 20032004 Swift 20042005 Astro-E 2 20052006 (GLAST) 20062009? Ne. XT 20072012? Constellation-X 20082015? ? XEUS, Maxim Pathfinder 20092025? ? ? Generation X, Maxim X-ray Astronomy School 2002