1. June 2 2004X-Ray Spectroscopy with Microcalorimeters1 X-Ray Spectrometry with Microcalorimeters

2. June 2 2004X-Ray Spectroscopy with Microcalorimeters2 Electromagnetic Spectrum

3. June 2 2004X-Ray Spectroscopy with Microcalorimeters3

4. June 2 2004X-Ray Spectroscopy with Microcalorimeters4 Cassiopeia A in the Opticaland the X-Ray Bands

5. June 2 2004X-Ray Spectroscopy with Microcalorimeters5 Cas A (soft) red (medium) green (hard) blue X-rays

6. June 2 2004X-Ray Spectroscopy with Microcalorimeters6 1 eV 100 eV 10 eV Energy (keV) The need for high resolution X-ray spectroscopy Astrophysical Plasmas: Simulation of the emission from a gas at T = 10 7 K with normal abundances of elements. An energy resolution of ~ 10 eV is required to begin serious X-ray spectroscopy and a resolution of ~ 1 eV is required for complete plasma diagnostics and velocity measurements.

7. June 2 2004X-Ray Spectroscopy with Microcalorimeters7 Energy-Selected X-ray Imaging Cassiopeia A ACIS spectrum 4-6 keV

8. June 2 2004X-Ray Spectroscopy with Microcalorimeters8 Cassiopeia A: Ejecta Knots Temperatures are comparable ~ 2 keV Si-rich knots have low ionization age (electron density x time) Fe-rich knots have ionization ages that are higher by ~50-100 Si S Ar Fe LFe K Ca Si S Ar Ca

9. June 2 2004X-Ray Spectroscopy with Microcalorimeters9 Physical Conditions Through X-Ray Spectroscopy Fe-K lines provide very clean diagnostics. One such diagnostic: excellent density-independent temperature sensitivity in the range 10 7 –10 8 Kelvin. x y z wHe-like Fe “triplet” Energy (keV) Counts Expected with XRS (12 eV) Chandra HEG (~ 60 eV) w y, x z Neutral Fe He-like Fe H-like Fe

10. June 2 2004X-Ray Spectroscopy with Microcalorimeters10 The X-ray Microcalorimeter Features high resolution, non-dispersive spectroscopy with high quantum efficiency over K- and L- atomic transition band. Moseley, Mather and McCammon 1984

11. June 2 2004X-Ray Spectroscopy with Microcalorimeters11 Simple Energy Resolution Argument δT = E/C (temperature rise for E deposition) C ≈ Nk (N = # of phonons with ) N ≈ C/k (fluctuation in N is the “noise”) ΔN = √N (Poisson statistics) R = E/(ΔE) = N/(ΔN) (resolving power) ΔE ≈ kT √N ≈ kT √(C/k) ≈ √(kT 2 C) More carefully, ΔE = 2.35 ζ √(kT 2 C)

12. June 2 2004X-Ray Spectroscopy with Microcalorimeters12 Spectral Resolving Power: Depends on thermometer technology Temperature-sensitive resistance Resolution limited by thermal fluctuations between sensor and heat bath and Johnson noise. Doped semiconductor Superconducting Transition T = operating temperature (50-100 mK) C = heat capacity  ~ 2 - 4 for doped semiconductors ~ 0.2 for transition edge sensors For both thermometer schemes a spectral resolution of few a eV is possible! R (ohms) Temperature

13. June 2 2004X-Ray Spectroscopy with Microcalorimeters13 Types of thermometers: resistive capacitive inductive paramagnetic electron tunneling Basic requirements: Low temperature Sensitive thermometer Thermal link weak enough that the time for restoration of the base temperature is the slowest time constant in the system yet not so weak that the device is made too slow to handle the incident flux. Absorber with high cross section yet low heat capacity Reproducible and efficient thermalization

14. June 2 2004X-Ray Spectroscopy with Microcalorimeters14...... Microcalorimeter Arrays XQC Array: 36 array of 0.5  2 mm pixels.

15. June 2 2004X-Ray Spectroscopy with Microcalorimeters15 X-Ray Quantum Calorimeter Dewar

16. June 2 2004X-Ray Spectroscopy with Microcalorimeters16 Astro-E2 Astro-E2 is a powerful X-ray observatory developed jointly by the US and Japan (Institute of Space and Astronautical Science). High x-ray spectral resolution throughout energy band where bulk of astrophysically abundant elements exist (O - Ni) Non-dispersive spectrometers enable imaging spectroscopy of extended sources Large collecting area for high sensitivity Very large simultaneous bandwidth Complementary to Chandra and XMM- Newton X-ray Observatories

17. June 2 2004X-Ray Spectroscopy with Microcalorimeters17 XRT (GSFC & ISAS) XIS (ISAS & MIT) HXD (ISAS) Astro-E 2 GSFC/ISAS XRS Focal Lengths XRS - 4.5 m XIS - 4.75 m

18. CCD Response He-like Fe K Z = 0.01 (3000 km/sec) X-Ray Image Astro-E2/XRS Simulation of the Centaurus Cluster Astro-E2 ideal for for obtaining x-ray spectra of extended sources. Ar S Ca Si Mg O Fe-L Ne Ni

19. June 2 2004X-Ray Spectroscopy with Microcalorimeters19 Developed process to make ion-implanted Si thermistors with deeper profiles using silicon-on-insulator wafers. Essentially eliminated 1/f noise  higher resolution! Appropriate thermal conductance achieved with thinner Si; no need to perform texturing etch to beams to make them diffusive. DRIE to form pixels with good mechanical properties. Ion beam 1.5  m ~ 6 times deeper thermometer (after anneal) New Microcalorimeter Design

20. June 2 2004X-Ray Spectroscopy with Microcalorimeters20 E Energy (keV) 6.4 eV FWHM Ion beam 1.5  m ~ 6 times deeper thermometer (after anneal) Deep implants using silicon-on-insulator wafers. 625  m pixels Mn K   Mn K   GSFC

21. June 2 2004X-Ray Spectroscopy with Microcalorimeters21

22. June 2 2004X-Ray Spectroscopy with Microcalorimeters22 RTS – Rotating Target Source continuum X-ray source X-ray continuum X-ray lines targets (one is open for continuum) rotating target wheel

23. June 2 2004X-Ray Spectroscopy with Microcalorimeters23 target wheel motor

24. June 2 2004X-Ray Spectroscopy with Microcalorimeters24

25. June 2 2004X-Ray Spectroscopy with Microcalorimeters25

26. June 2 2004X-Ray Spectroscopy with Microcalorimeters26 NTD Calorimeter with Sn Absorbers SAO Silver et al.

27. June 2 2004X-Ray Spectroscopy with Microcalorimeters27 14801485149014951500 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 Toward higher spectral resolution and large arrays: Transition edge microcalorimeters 4.5 eV SRON, 4.5 eV, 100  s time constant, 30 min acquisition time

28. June 2 2004X-Ray Spectroscopy with Microcalorimeters28 Microcalorimeter Arrays based on Mo/Au TES Bi Sharp photolithography Array of identical 150 micron devices. Soon will make these with 250 and 400 micron “mushroom” absorbers. The Bi absorbers shown are the size of the stem in the mushroom. Array of identical devices GSFC

29. June 2 2004X-Ray Spectroscopy with Microcalorimeters29 Energy (keV) Counts Energy Resolution = 2.5 eV (FWHM) Mo/Au TES Compact pixel design (300  m) Continuous membrane thermal isolation Results from Compact TES Pixels Paves the way for faster, more robust pixels for the Constellation-X Mission. GSFC 1024 pixel absorber array