Can dTCMB/dt be Measured?

R. V. DuncanUniversity of New Mexico, and Caltech

Quarks to Cosmos WorkshopAirlie Center, May 23, 2006Work sponsored by NASA, and by and equipment loan from Sandia National Labs

Acknowledge helpful discussions with Prof. George Seidel (Brown) and Prof. Philip Lubin (UCSB)

Why?Fundamental test of cosmological theoriesHubbles Law: v = H DH is very uncertain, 45 90 km/s per MpcT-1 dT/dt ~ D-1 dD/dt = v / D = H, hence a direct measurement of Hubbles Constant. Vastly improved long-baseline stability for all space radiometry applicationsQuasar / Black Hole / etc. radiation variation Anisotropy stability studiesAnticipate dTCMB/dt ~ 200 pK/year

An Exceptionally Hard Experiment

Photon Collection from a faint 2.7 K source:To resolve DT/T ~ 10-11 requires Averaging time ~ one month

Foreground Sources:Hubble Ultra - Deep Field:SW of Orion in Constellation Fornax,chosen for sparce foreground sources.

0.05 arc degrees

Metrology: BB stable to within 100 pK over decades!

New Ultra-Stable PlatformC. J. Green, D. A. Sergatskov, and R. V. Duncan, J. Low Temp. Phys. 138, 871 (2005).12

1. Paramagnetic Susceptibility Thermometry

Magnetic flux is trapped in aniobium tube

A paramagnetic substance with T > Tc is thermally anchored to the platform M = H c(T)

c(T) = G [(T Tc)/Tc]-g so small changes in T create large changes in M

Gifford, Web, Wheatley (1971)Lipa and Chui (1981)

PdMn: Klemme et al., JLTP 116, 133 (1999) Nelson, Sergatskov, & Duncan, JLTP 127 173 (2002)

HPd Mn

PdMn0.9% Thin Film Magnetic Susceptibility ThermometrySee R.C. Nelson et al., JLTP (2002) For thermometry, See Duncan et al., 2nd Pan Pacific Basin Workshop, 2001.Thin film sensitivity vs. T and HNo hysteresis was observed

Chart2

1.36792044.579559610.951859613.3988228

1.7654045.825833212.96178215.2196408

2.3958257.53410514.8235316.88292

3.3574719.87029116.94456118.460476

4.70566412.87539219.6172820.337408

7.21060116.62712221.57665521.769673

11.02674321.14612523.8374523.468354

3.373.373.373.37

17.09811225.92294425.61269624.47512

24.87317730.34877127.35855326.01878

31.31803232.46166828.78883726.699502

334.04974529.5147927.0594

34.3180134.6051929.83800227.684152

2.82.82.827.99485

33.3950434.7533730.0157827.13347

31.59536434.78953629.59419627.51606

29.81052233.68318829.09002627.198724

28.09254532.34094528.94222526.97734

26.26956831.00566828.29030426.080124

24.407629.486227.28824.7866

2.32.32.325.9236

22.33461628.21698426.773965625.000064

2.22.22.224.81624

20.971526.38352.124.354

2.12.12.124.1285

19.3586423.9878825.5309623.8476

2225.25042

1.921.9224.80541.92

18.2629323.404921.91.9

1.871.871.871.87

16.60990963581.831.831.83

1.822.607641.81.8

1.71822.19966737191.7181.718

1.711.711.711.71

6 G

35 G

150 G

250 G

Temp (K)

Sensitivity (flux quanta/mK)

Sensitivity

Decreasing Tshiftfield

Temp (K)12.5 G6 G35 G35 Gauss6 Gauss6 Gauss70 Gauss150 Gauss250 Gauss250 Gauss3.90%6 gauss

0.403542.23455321.30844564.57955961.3594241.36792047.2219410.951859613.398822813.39882285.80%35 Gauss

0.36843.92.9733121.74682085.82583321.80257041.7654048.947810812.96178215.219640815.21964084.60%250 Gauss

0.33333.83.9454652.365247.5341057.4525452.44682.39582511.08196514.8235316.8829216.88292

0.29823.75.4236073.2002659.8702919.7916883.3462423.35747113.82289916.94456118.46047618.460476

0.26323.67.6606724.65612.87539212.8008964.70566417.04716819.6172820.33740820.337408

0.22813.511.0433876.96243516.62712216.7236317.2795367.21060120.47369521.57665521.76967321.769673

0.19303.410.65764721.14612521.51522111.10363811.02674323.82207123.8374523.46835423.468354

0.18253.3717.606654

0.15793.322.1482616.85680825.92294426.1125417.35665217.09811226.93986825.61269624.4751224.47512

0.12283.227.5721424.34891830.34877129.63034224.62075624.87317729.49442327.35855326.0187826.01878

0.08773.130.21838230.83418632.46166832.39568931.34002531.31803231.42799728.78883726.69950226.699502

0.0526333.2229333.59875534.04974534.14996534.50073532.89721529.5147927.059427.0594

0.01752.935.70152634.26057434.6051934.72006234.69134434.3180133.25544429.83800227.68415227.684152

2.827.9948527.99485

-0.01752.836.595928310930.0157834.7533735.0846733.1962633.3950433.2956530.0157827.1334727.13347

-0.05262.735.027826433830.90265234.78953634.71256831.59536431.59536433.13472429.59419627.5160627.51606

-0.08772.634.046500360929.58536733.68318833.05275430.21580129.81052232.06207229.09002627.19872427.198724

-0.12282.531.567946690827.45528532.34094532.34094527.66770528.09254531.2257428.94222526.9773426.97734

-0.15792.430.572545253825.76438431.00566831.06881626.14327226.26956830.37418828.29030426.08012426.080124

-0.19302.328.754596784323.649629.486229.410423.87724.407629.334627.28824.786624.7866

2.325.923625.9236

-0.22812.226.794275198521.5993228.21698427.75742422.33461622.33461628.4927226.773965625.00006425.000064

2.224.8162424.81624

-0.26322.124.66485235219.618526.383526.383520.1822520.971526.834525.3687524.35424.354

2.124.128524.1285

-0.2982222.987244470818.5169623.9878825.3906819.3586419.3586426.653225.5309623.847623.8476

225.2504

-0.32631.9224.8054

-0.33331.921.182964890616.8444523.4049223.7595417.73118.2629325.6940921054

-0.34391.8720.71486263615.52848

-0.35791.8316.609909635816.6099096358

-0.36841.822.6076422.60764

-0.39721.71822.199667371922.1996673719

-0.40001.7113.54905

26.0711

25.36875

0.0276856369

25.463

24.7866

0.0272889384

Sensitivity

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000000

000000

000000

000000

000000

000000

000000

000000

000000

000000

000000

000000

000000

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6 G

12.5 G

35 G

70 G

150 G

250 G

Temp (K)

Sensitivity (flux quanta/mK)

16219-4.0K

00

00

00

00

00

00

00

00

00

00

00

00

00

00

00

00

00

00

00

00

00

00

00

00

00

00

00

00

00

00

00

00

00

00

00

00

H = 35 gauss

Decreasing T

Increasing T

Temp (K)

Sensitivity (flux quanta/mK)

Sensitivity of PdMn film

15219-3.9K

0

0

0

0

0

0

0

0

0

0

Reduced Temperature

Sensitivity (flux quanta/mK)

13219-3.8K

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

Reduced Temperature

Sensitivity (flux quanta/mK)

Sensitivity of PdMn film

12219-3.7K

0000

0000

0000

0000

0000

0000

0000

0000

0000

0000

0000

0000

0000

0000

0000

0000

0000

0000

0000

0000

0000

0000

0000

0000

0000

0000

0000

0000

0000

0000

0000

0000

0000

0000

0000

0000

35 G

70 G

150 G

250 G

Temp (K)

Sensitivity (flux quanta/mK)

Sensitivity of PdMn film

11219-3.6K

00

00

00

00

00

00

00

00

00

00

00

00

00

00

00

00

00

Decreasing T

Temp (K)

Sensitivity (flux quanta/mK)

150 gauss

10219-3.5K

00

00

00

00

00

00

00

00

00

00

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

First pass

Second pass

Temp (K)

Sensitivity (flux quanta/mK)

250 Gauss

09219-3.4K

0-3.102531565.2-3.10253

2-3.085221565.3-3.08522

3-3.063331565.5-3.06333

4-3.046581565.7-3.04658

5-3.022481565.9-3.02248

8-2.965991566.3-2.96599

9-2.932381566.5-2.93238

10-2.903721566.7-2.90372

12-2.870671567-2.87067

13-2.830651567.3-2.83065

14-2.799071567.5-2.79907

15-2.759011567.8-2.75901

17-2.717121568.1-2.71712

18-2.679811568.3-2.67981

19-2.635731568.6-2.63573

20-2.591331569-2.59133Delta V-1570.2

22-2.548551569.3-2.54855zxzlzuAarccosxcos (I*arccos(x)

23-2.501361569.6-2.5013615653.1945143419-0.24040317682.25153911384.73437000324.5799781.813577514414.57997814.579978

24-2.45291569.9-2.452915753.1972805581-0.2381749008-4.6659241.8112825659-0.24040317681.1217029522-0.23817490081.1113059857

25-2.409691570.2-2.409691.618798-0.8844126252-1.4316853888-0.8865454333-1.4351379743

27-2.355531570.5-2.35553-0.3571330.6656343861-0.23772000520.660480642-0.2358794331

28-2.30711570.9-2.30710.0109220.56437138320.00616406420.57192561050.0062465715

29-2.258751571.2-2.258750.020675-0.9369877329-0.0193722214-0.9329172931-0.019288065

31-2.211671571.5-2.2116713.3988228-0.0082940.9917331752-0.0082254350.9936664896-0.0082414699

32-2.1613515