Status of Development of

Metallic Magnetic Calorimeters

A. Fleischmann, T. Daniyarov H. Rotzinger, M. Linck, C. Enss

Kirchhoff-Institut für PhysikUniversität Heidelberg

H. Eguchi, Y.H. Yong, G.M. SeidelDepartment of Physics

Brown University

2

Metallic Magnetic Calorimeter

Au:Er

H

3

Calorimeter Signal

122 keV in Au:Er 300ppm

• satisfying agreement of theory and experiment

• signal size can be predicted!

Resolution of optimized detector:

4

Gradiometer With Two Sensors: Two-Pixel Detector

performance of pixels almost identical

commercial SQUID chipM.B. Ketchen, IBM 1992

50 μm

5

two Au:Er 300 ppm sensors

Gold absorber: 160 x 160 x 5 m3

Heat capacity corresponds to a Bi absorber of 250 x 250 x 28 m3

MMC Detector 2003

160 μm x 160 μm x 5 μm

clean spectrum

Kα

Kβ

6

Resolution: Kα-Line 55Mn

energy resolution 3.4 eV

Raw Data

natural linewidth

7

Kβ-Line 55Mn

A. Fleischmann, M. Linck, T. Daniyarov, H. Rotzinger, C. Enss, G.M. Seidel, Nucl. Instr. and Meth. A 520, 27 (2004).

8

Baseline Noise

two Au:Er 300 ppm sensorsGold absorber: 160 x 160 x 5 m3

one Au:Er 300 ppm sensorsGold absorber: 160 x 160 x 5 m3

Spectrum: 3.5 eV because of Temperature stabilization problems

9

E/E at 6 keV

ionisation detectors

2 eV

6 eV

3.4 eV

10

Predicted Resolution for Different Detectors

Resolution:

Energy range: 1 ... 6 keV

250 x 250 x 5 m3, Bi absorber

Au:Er 900 ppm sensor, 35 m, h = 14 m

T = 50 mK, 0 = 10-6 s, 1 = 10-4 s

EFWHM = 0.7 eV

Energy range: 0.25 ... 0.6 keV

120 x 120 x 0.5 m3, Bi absorber

Au:Er 900 ppm sensor, 20 m, h = 8 m

T = 50 mK, 0 = 10-6 s, 1 = 10-4 s

EFWHM = 0.1 eV

11

MMC Detectors for X Ray Astronomy

increase detector speed

not a problem

micro-fabrication of MMCs

schemes for arrays and multiplexing

a problem, but likely to be solvable

a very complex problem

spot welded detector heat capacity 10-9 J/K

12

MMC Arrays for X Ray Astronomy

speed

cross talk

efficiency

homogeneity

power dissipation

signal to noise

complexity

stability

coupling schemes

fabrication techniques

layout and wiring schemes

signal analysis

schemes

readout schemes

?

?MMC specific : non-contact readout

non-dissipative method

13

Informal Collaboration on MMCs for Astronomy

S.R. BandlerT.R. StevensonF.S. PorterE. Figueroa-FelicianoC.K. StahleR. Kelley

S. Romaine R. Bruni

A. FleischmannM. LinckT. DaniyarovH. RotzingerA. BurgC. Enss

Berlin

SAO

G.M. SeidelY.H. KimY.H. HuangH. Eguchi

K.D. IrwinB.L. ZinkG.C. Hilton D.P. Pappas J.N. UllomM.E. Huber, Uni. Colorado

Heidelberg

Goddard

Boulder

J. BeyerD. DrungT. Schurig

H.-G. MeyerR. StolzS. Zarisarenko

Jena

14

SAO

development of deposition techniques for Au:Er

integrate Au:Er sensors on SQUID chips

15

NASA - GSFC

development of suitable absorbers Bi:Cudevelop means of fabricating MMC mushrooms investigating different transformer schemes development of position sensitive MMCs

MMC MMC

16

NIST Boulder

development of integrated MMCsinvestigating new schemes for MMCs: self-inductance MMCsdevelop optimized SQUIDs explore new multiplexing techniquesdevelop fabrication methods

OptimizedSQUID

Co-evaporatedAu:Er Sensor

Film

Self-InductanceMeander

Transformer

17

PTB Berlin

development of optimizied SQUIDs

high speed low-noise readout electronics

10-1 100 101 102 103 104 105 106 107

1

10

f / Hz

T = 4.2 K

SI

/ (p

A/

Hz)

18

IPTH Jena

development of optimized SQUIDs

low noise readout electronics

optimized sensor design

19

Brown/Heidelberg

investigate alternative sensor materialsstudy fundamental noisedevelop new sensor geometries develop deposition techniques for Au:Eroptimize single pixel performancestudy properties of small arrays

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MMCs can be a new exciting tool for X-ray astronomy

Let’s work to make it happen

Summary

SOHO 304 Å

21

Problem: Slewrate too low

slew rate of SQUID too low (100 0/ms)

limits the usable signal size

feedback of Ketchen-SQUID to weak