# Presentation: 494878

## The Future of X-ray Astronomy

- Keith Arnaud
- NASA/GSFC and UMCP

- X-ray Astronomy School 2002

## Theme

-  Polarimetry
-  Interferometry

-  In the first 40 years of X-ray astronomy we increased sensitivity by a factor of 109, image resolution by 2.5x105, spectral resolution by 104. How do we keep this progress up for the next 40 years ?

- X-ray Astronomy School 2002

## Calorimetry

- 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.

- Stahle

- X-ray Astronomy School 2002

## X-ray calorimetry

- Stahle

- X-ray Astronomy School 2002

## Microcalorimeters vs. Gratings

-  Resolutions comparable with gratings. Microcalorimeters win at high energies, gratings at low energies.
-  Non-dispersive so :
-  high efficiency
-  low background
-  no problems for extended sources
-  wide bandpass
-  However, microcalorimeters are cryogenic experiments requiring cooling to ~60 mK.

- 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 eV FWHM
- (0.5 - 10 keV)

- 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-E2 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

## Slide 18

- X-ray Astronomy School 2002

## Slide 19

- X-ray Astronomy School 2002

## Slide 20

- X-ray Astronomy School 2002

## Constellation-X Overview

- Black holes: strong gravity & evolution
- Large scale structure in the Universe & trace the underlying dark matter
- Production and recycling of the elements

**Mission parameters**
**Telescope area:** 3 m2 at 1 keV
***100 times XMM/Chandra for high res. spectra***
**Spectral resolving power:** 300-3,000
***   ******5 times improvement at 6 keV***
**Band pass:** 0.25 to 40 keV
***100 times more sensitive at 40 keV ***

- X-ray Astronomy School 2002

## Calorimeter developement

- 1480

- 1485

- 1490

- 1495

- 1500

- 1505

- 0

- 20

- 40

- 60

- 80

- 100

- 120

- Energy (eV)

- Counts per 0.25 eV bin

- Instrument Resolution:
- 2.0  0.1 eV FWHM

- Al K1,2

- Al K3,4

- Bismuth absorber

- TES Al/Ag bilayer

- 450 counts/sec

- K. Irwin

- X-ray Astronomy School 2002

## Goddard Mo/Au TES:

- 2.4 +/- 0.2 eV at 1.5 keV and
- 3.7 +/- 0.2 eV at 3.3 keV.

- Al K
- into 300 x 300 micron TES

- K K
- into 500 x 500 micron TES

- X-ray Astronomy School 2002

## McKee-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

-  6 m2 of collecting area at 1 keV.
-  Imaging resolution goal of 2" HEW (Half Energy Width) at 1 keV.
-  Limiting sensitivity 100 times deeper than XMM-NEWTON.

-  Spectral resolution of 1 to 10 eV between 0.05 and 30 keV.

- X-ray Astronomy School 2002

## XEUS II

-   New detector spacecraft with next generation of focal plane technologies.
-  Grown mirror will have 30 m2 collecting area at 1 keV;  3 m2 at 8 keV.
-   Sensitivity 250 times better than XMM-NEWTON.

- X-ray Astronomy School 2002

## Con-x

- X-ray Astronomy School 2002

## Generation X

-  Scientific goal:  to probe the X-ray emission from the universe at z = 5-10.
-  An effective area of 150 m2 at 1 keV with an angular resolution of ~ 0.1 arc second.
-  Detect sources 1000 times fainter than Chandra  (flux limit of 2 x 10-20 ergs/cm2/s).
-  Obtain high resolution spectra from sources 100-1000 x fainter than observable by Constellation-X.
-  Six identical satellites with 40 to 150 m focal length to L2.

- X-ray Astronomy School 2002

## Telescope Evolution

## 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 1970s.
-  There is a new idea for a more efficient polarimeter...

- X-ray Astronomy School 2002

## Polarization

## Electron Tracks

- Bellazzini et al.

- X-ray Astronomy School 2002

## Microwell detector

- Bellazzini et al.

- X-ray Astronomy School 2002

## Bellazzini et al.

- X-ray Astronomy School 2002

## Accumulation of many events

- Bellazzini et al.

- X-ray Astronomy School 2002

## 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

## Slide 44

- X-ray Astronomy School 2002

## Slide 45

- X-ray Astronomy School 2002

## Slide 46

- X-ray Astronomy School 2002

## MAXIM Pathfinder

- Milliarcsecond resolution

## Timeline

-           (Integral)
- 2004          Swift
- 2005          Astro-E2
- 2006          (GLAST)
- 2009?        NeXT
- 2012?        Constellation-X
- 2015??      XEUS, Maxim Pathfinder
- 2025???    Generation X, Maxim

- X-ray Astronomy School 2002