R. Stern (LMSAL) , X-ray Workshop, TMU, JapanR. Stern (LMSAL) , X-ray Workshop, TMU, Japan June 22, 2006

Progress in TES Detector Development forProgress in TES Detector Development forSolar and Astrophysical Research at LMSALSolar and Astrophysical Research at LMSAL

Robert Stern, Robert Stern, Steve Deiker, , Dennis Martínez-Galarce, , Adam Rausch, Lawrence Shing (LMSAL*)

+NIST, Stanford, Santa Clara U. & LM ATC

*Lockheed Martin*Lockheed Martin

Solar and Astrophysics LaboratorySolar and Astrophysics LaboratoryLM Advanced Technology CenterLM Advanced Technology Center

stern@lmsal.comstern@lmsal.com

Progress in TES Detector Development forProgress in TES Detector Development forSolar and Astrophysical Research at LMSALSolar and Astrophysical Research at LMSAL

Robert Stern, Robert Stern, Steve Deiker, , Dennis Martínez-Galarce, , Adam Rausch, Lawrence Shing (LMSAL*)

+NIST, Stanford, Santa Clara U. & LM ATC

*Lockheed Martin*Lockheed Martin

Solar and Astrophysics LaboratorySolar and Astrophysics LaboratoryLM Advanced Technology CenterLM Advanced Technology Center

stern@lmsal.comstern@lmsal.com

R. Stern (LMSAL) , X-ray Workshop, TMU, JapanR. Stern (LMSAL) , X-ray Workshop, TMU, Japan June 22, 2006

OutlineOutline

• Some science motivation: why are microcalorimeters useful in solar physics ?

• Characteristics of a solar physics X-ray mission concept using TES’s

• Laboratory work at LMSAL on TES’s, ADRs

• Applicability to astrophysical X-ray instruments

• Summary

R. Stern (LMSAL) , X-ray Workshop, TMU, JapanR. Stern (LMSAL) , X-ray Workshop, TMU, Japan June 22, 2006

Exploring Magnetic Reconnectionin the Solar Corona

Exploring Magnetic Reconnectionin the Solar Corona

• New instruments needed to investigate dynamics of faint (EM < 1046 cm-3), hot ( > 107 K) material produced by reconnection in microflares and early stages of solar flares

– previous flare instruments were mostly based on Bragg Xtal spectrometers with limited (SMM BCS) or no (Yohkoh BCS) imaging capability and very low effective area (0.025-0.1 cm2)

• RHESSI (RMC + cooled HP Ge detector) is seeing many such microflaring events, but has limited spectral resolution at low energies ( ~1 keV at 3-10 keV)

• High spectral ( R > 1000), spatial, and time resolution of hot (>10MK) plasma (e.g Fe XXV) is required (same Fe K-shell lines as seen in astrophysical sources)

R. Stern (LMSAL) , X-ray Workshop, TMU, JapanR. Stern (LMSAL) , X-ray Workshop, TMU, Japan June 22, 2006

RHESSI Fe Line ResultsRHESSI Fe Line Results

•SMEX Launched (finally) in February 2002

•HP Ge (cf. HEAO-3) photon counter with RMC (cf. Minoru Oda, HINOTORI)

•designed for hard (> 10keV) X-ray and gamma ray imaging and spectroscopy, but has ~15 cm2 at Fe XXV (6.7 keV) with ~ 1 keV FWHM, ~5 "

(Liu et al. 2004)

R. Stern (LMSAL) , X-ray Workshop, TMU, JapanR. Stern (LMSAL) , X-ray Workshop, TMU, Japan June 22, 2006

Hannah et al. (2004) SOHO WorkshopHannah et al. (2004) SOHO Workshop

R. Stern (LMSAL) , X-ray Workshop, TMU, JapanR. Stern (LMSAL) , X-ray Workshop, TMU, Japan June 22, 2006

Explorer Class Mission ConceptExplorer Class Mission Concept

• Science driven: reconnection physics throughout cycle

• 3-8 keV bandpass, < 4 eV energy resolution (R~1700 at Fe XXV 6.7 keV complex)

– Combination allows LOS velocity determination to 200 km s-1 and better with centroiding + velocities perpendicular to LOS – 3D velocity field

• Grazing Incidence Telescope - Focal Length ~2 m

• FOV ~ 2.5 – 3 arc-min with ~few arcsec resolution

• Count rate > 103 c/s for event studied (accumulate 10Kct spectrum in 10 sec); time stamping of photon events to sec accuracy

R. Stern (LMSAL) , X-ray Workshop, TMU, JapanR. Stern (LMSAL) , X-ray Workshop, TMU, Japan June 22, 2006

Simulated TES Solar Explorer Spectrum from FeXXV Complex (20 MK) using CHIANTI

Simulated TES Solar Explorer Spectrum from FeXXV Complex (20 MK) using CHIANTI

“RHESSI”-like microflare / 4 eV FWHM

SMM BCS

(~1.25 mA thermal width)

R. Stern (LMSAL) , X-ray Workshop, TMU, JapanR. Stern (LMSAL) , X-ray Workshop, TMU, Japan June 22, 2006

Key Technology Developments Needed Key Technology Developments Needed • Up till now, most technology for X-ray TES driven by, e.g.,

Constellation-X, NeXT and XEUS (10-50 m focal lengths)

• Small solar payload with F.L ~ 2 m needs effective pixels of 10-20 m or so

• Smaller effective pixels also help larger missions such as RAM (Reconnection And Microscale Mission)

• Solar payloads need large number of spatial resolution elements to cover active region with high angular resolution

– will likely require “tiled” or modular focal plane

• High countrate ( kcts/sec) in microflare/flare region to accumulate spectrum quickly

• Low mass cryocooler + Adiabatic Demagnetization Refrigerator (ADR) with long life

R. Stern (LMSAL) , X-ray Workshop, TMU, JapanR. Stern (LMSAL) , X-ray Workshop, TMU, Japan June 22, 2006

Current Program of TES Research at LMSALCurrent Program of TES Research at LMSAL

• Operate NIST-supplied devices (single pixel on NIST array)

– Fe55 X-ray spectrum from 1st gen setup; 2nd gen in progress

• Recent SR&T awards (Solar & Heliospheric) from NASA

– Position Sensitive X-ray Strip Detectors (with NIST, SU)

– Al:Mn Magnetically Insensitive TES (with Santa Clara, SU)

• Solar TES Rocket (lower energies ~ 1 keV) – with SU, LLNL

• New initiative: rocket ADR adapted for TES/SQUID readout (with LMATC Thermal Group, U. Wisconsin)

• Pending: collaboration with MIT (Tali Figueroa), GSFC, U. Wisc on X-ray imaging TES rocket payload

• Current goals: solar X-ray TES Explorer; Reconnection and Microscale Mission (long term)

R. Stern (LMSAL) , X-ray Workshop, TMU, JapanR. Stern (LMSAL) , X-ray Workshop, TMU, Japan June 22, 2006

Key Collaborators in TES InstrumentationKey Collaborators in TES Instrumentation

• NIST (TES’s, SQUIDs, Strip Detectors)

– Kent Irwin, Gene Hilton, Joel Ullom, Randy Doriese

• Stanford (TES principles, Al:Mn, Lab ADR experience)

– Blas Cabrera, Paul Brink, Steve Leman, T.J. Bay

• Santa Clara University (Al:Mn devices)

– Betty Young

• University of Wisconsin (Rocket ADR)

– Dan McCammon

• Lockheed Martin Advanced Technology Center Thermal Sciences Department (cryogenic technology, rocket ADR project)

– Ted Nast, Dean Read

R. Stern (LMSAL) , X-ray Workshop, TMU, JapanR. Stern (LMSAL) , X-ray Workshop, TMU, Japan June 22, 2006

Fe55 Spectrum With 1st Generation Base StageFe55 Spectrum With 1st Generation Base Stage

Mn K-α and K-β.

Measured resolution is 15.5 eV FWHM

(late 2005)

Single pixel achieved 2.4 eV FWHM(at NIST)

LMSAL Lab Base Stage

•Need improved LMSAL base stage/noise reduction to separate

Kα1, Kα2

R. Stern (LMSAL) , X-ray Workshop, TMU, JapanR. Stern (LMSAL) , X-ray Workshop, TMU, Japan June 22, 2006

2nd Generation Base Stage2nd Generation Base Stage

Nb shield

1st stage SQUID slots (4)

TES Slot

Improvements:

• Full Nb shield,

• Axis of field-canceling coil perpendicular to axis of SQuID coils

• Accomodates thermometry near TES,

• Easier bonder access

• Decreased size / weight.

(under construction)

R. Stern (LMSAL) , X-ray Workshop, TMU, JapanR. Stern (LMSAL) , X-ray Workshop, TMU, Japan June 22, 2006

NIST/LMSAL Strip Detector ConceptNIST/LMSAL Strip Detector Concept

•32 parallel 10m wide strips each 320m long with ~ 10m position resolution (32 x 32 at 2m FL) MUXed at each end

Prototype Array

R. Stern (LMSAL) , X-ray Workshop, TMU, JapanR. Stern (LMSAL) , X-ray Workshop, TMU, Japan June 22, 2006

Strip Detector Test Wafer (LMSAL/NIST Grant(s) from NASA)Strip Detector Test Wafer (LMSAL/NIST Grant(s) from NASA)

with Pd

layer

(6/06)

R. Stern (LMSAL) , X-ray Workshop, TMU, JapanR. Stern (LMSAL) , X-ray Workshop, TMU, Japan June 22, 2006

4

5

6

7

8

9

10-6

2

3

No

ise

(V/r

tHz)

101

102

103

104

Frequency (Hz)

Zero Field ~500 mgauss

500

400

300

200

100

TC

(m

K)

200018001600140012001000

Mn Concentration (ppm)

•Simplicity of fabrication.

• Low noise

•comparable to bi-layers

• Design flexibility (not limited in thickness).

• Apparent insensitivity to magnetic fields.

Manganese-doped Aluminum TES (NASA Grant with SU and SCU)

Alternative to bi-layers:

R. Stern (LMSAL) , X-ray Workshop, TMU, JapanR. Stern (LMSAL) , X-ray Workshop, TMU, Japan June 22, 2006

Lockheed Martin Rocket ADR re-design (collab with U. Wisc.)

Modify Design and Construct 3-D Solid Model

Original U. of Wisc.design

McCammon et al 2002

Low magnetic field required

for TES operation

R. Stern (LMSAL) , X-ray Workshop, TMU, JapanR. Stern (LMSAL) , X-ray Workshop, TMU, Japan June 22, 2006

Magnetic Field ModelingMagnetic Field Modeling

Status:•2nd iteration of design; FEM dynamics analysis to be re-run•Order and test magnet/shield in CY 2006•Modify with additional shielding/bucking coil if required

Full 8.5 A => 4 T in core Operating ~ 150 mA => 700 G in core

Detector plate

Passive Shields: Van. Perm. or Cryoperm

≤ 3 G at detector plane B-field at detector ≤ 0.05 G

R. Stern (LMSAL) , X-ray Workshop, TMU, JapanR. Stern (LMSAL) , X-ray Workshop, TMU, Japan June 22, 2006

Astrophysics ApplicabilityAstrophysics Applicability

• Strip detectors

– Short focal length telescopes

– Multiplex capability results in fewer wires/resolution element

• Al:Mn

– detector thickness constraint removed

– potential to significantly reduce magnetic shield requirements

• Prototype (Rocket) ADR

– new design will provide flight test of TES/SQUID operation

R. Stern (LMSAL) , X-ray Workshop, TMU, JapanR. Stern (LMSAL) , X-ray Workshop, TMU, Japan June 22, 2006

SummarySummary

• LMSAL (with considerable help from NIST/SU/ Wisc./SCU) is pursuing a vigorous program of TES-related research focused on solar physics (with potential applicability to astrophysics)

• Laboratory work (begun ~ 2 ½ yrs ago) is close to achieving noise goals for single-pixel devices

• Position-sensitive strip detectors have been fabricated and are about to begin testing at NIST and LMSAL.

• Al:Mn detector work with SCU/SU has begun

• ADR Prototype design for TES solar rocket is nearly complete; magnet/shielding tests to begin this year