matt dobbs- probing the opposite ends of time with the cosmic microwave background radiation

8/3/2019 Matt Dobbs- Probing the opposite ends of time with the Cosmic Microwave Background Radiation

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Cosmic MicrowaveCosmic Microwave

Background RadiationBackground Radiation

Matt DobbsMatt Dobbs

October 27, 13 700 002 006 ABB

Probing the opposite ends of time with the

[email protected]– Oct 27, 2006

Spiral Galaxy

From our perspective asFrom our perspective as

optical observers, theoptical observers, theuniverse is a richuniverse is a rich

place full of structure,place full of structure,

detail and beauty.detail and beauty.


“Photograph” of the universe in the Microwave band.Real Experimental DATA from the COBE satellite, 1992.

Q: Where are we in the universe?

A: Nowhere special(on cosmological scales)


What is cosmology?What is cosmology?

Step back to larger scales, andStep back to larger scales, and

the universe that surrounds usthe universe that surrounds us

is extremely uniformis extremely uniform – –

on large (Cosmological) scales,on large (Cosmological) scales,

the universe isthe universe is homogenous (the samehomogenous (the same

everywhere)everywhere)

isotrophicisotrophic (looks the same in(looks the same in

every direction)every direction)

Loosely put,Loosely put, cosmology is the cosmology is the

study of our universe on study of our universe on

these scales these scales ..

This infinite cylinder is a 2dhomogeneous surface, but it is notisotrophic.

The 2d surface of this sphereis isotrophic, and thereforealso homogeneous.




EM SpectrumEM Spectrum


different information is encoded in different bands.different information is encoded in different bands.

radiowavesradiowaves: i.e. radar: i.e. radar

visible: this is how we see the world around us. visible: this is how we see the world around us.

xx--rays: i.e. dentist/doctor.rays: i.e. dentist/doctor.

gammagamma--rays: highest energy particles we know of…rays: highest energy particles we know of…

hot

cold

cmkm10-2-103 m

mmcm10-3-10-2 m

μm10-6-10-4 m

100s nm10-7-10-6 m

1-102 eV

102-105 eV

>105 eV

CMB Photons now.

[email protected]– Oct 27, 2006hot

cold

cmkm10-2-103 m

mmcm

10-3-10-2 m

μm10-6-10-4 m

100s nm10-7-10-6 m

1-102 eV

102-105 eV

>105 eV

CMBPhotonsNow

as the universeexpands & cools, theCosmic BackgroundRadiation photonsare stretched,and evolve through

the EMspectrum.

“CMB” photons

a long time ago.

“CMB” photonsin the future.

A l l t h

e s e “ d i f f

e r e n t ” p h

o t o n s

t r a v e l

a t t h

e s a m

e s p e e

d, c = 3 x 1 0

8 m / s.


The HorizonThe Horizon

lightlight – – and indeed any informationand indeed any information – – cannot be transmittedcannot be transmittedfaster than thefaster than the speed of light, cspeed of light, c..

For a universe that is L=13.7 billion years old, informationFor a universe that is L=13.7 billion years old, informationcould be exchanged over a maximum distancecould be exchanged over a maximum distance LcLc..

This defines “ This defines “our horizonour horizon”.”.

As time moves forward, our horizon increases!. As time moves forward, our horizon increases!.

The H orizon problemThe H orizon problem: we see structures (e.g. the universe!!): we see structures (e.g. the universe!!)

that are uniform on superthat are uniform on super--horizon scales.horizon scales.




Since light coming from further away takesSince light coming from further away takes

longer to get here, the objects that emit thelonger to get here, the objects that emit the

light are from an earlier time, because the lightlight are from an earlier time, because the light was emitted a long time ago. was emitted a long time ago.

observations of distant objects areobservations of our universeat a younger age.



1021

10-10

1

106

>= Galaxies

Size (m) Object Force Expert

Stars &planets

Living Things

Atoms

10-9 Molecules

10-15 Neutrons/protons

G r a v i t y

InstinctRomanceBiology

PsychologistsTaxi Drivers

Biologists

E l e c t r

o m a g n

e t i s m Chemists

Pharmacists

Weak ForceStrong Nuclear Force

Nuclear &ParticlePhysicists

Cosmologists

Astronomers

Thanks to A. De Rujula for this slide idea.


on different length scales, different forces areon different length scales, different forces are

relevantrelevant – – and so we use different theories andand so we use different theories andequations.equations.




Physics TheoriesPhysics Theories

B i g

g e r

M a s s

f a s t e r

S p e

e d

s m a l l e r s i z e

NewtonianGravity

QuantumMechanics

Special Relativity

Particle PhysicsEW, QCD

?????String Thy?

General Relativity

We need this GrandUnified Theory tocalculate anythingnear the big bang!


The History of the UniverseThe History of the Universe

a photon’s journey from thea photon’s journey from theopposite ends of timeopposite ends of time


History of the universeHistory of the universe You are here

NOW (13.7 Billion years)

Surface of Last Scattering

Inflation? <10-35 seconds, 1016 GeVGravity waves produced

Plasma Epoch

Large Scale Structure

LHC probes this scale (TeV, 10-14s)

T I M E


History of the UniverseHistory of the Universe

The Big BangThe Big Bang

1920s & 30s: Hubble observed the universe is expanding.1920s & 30s: Hubble observed the universe is expanding. time=0Big Bang





InflationInflation

at t~10at t~10--3535 s ABB, the universe undergoes a phases ABB, the universe undergoes a phase

transition causing an explosive 10transition causing an explosive 103030 exponentialexponential

expansionexpansion

Inflation explains the horizon problem: why Inflation explains the horizon problem: why

CMB is isotropicCMB is isotropic

10-38 sinflation10-45 10-35 10-5

TIME

U N I V E R S E

S I Z E

1

10-60

I N F

L A T I O N



Plasma Epoch,Plasma Epoch, t <~ 400 000 yearst <~ 400 000 years

the universe is opaque to lightthe universe is opaque to light

matter and radiation are tightly coupledmatter and radiation are tightly coupled in in

thermal equilibrium thermal equilibrium

plasmaepoch

10-38 sinflation



RecombinationRecombination t~379 000 years ABB, T=3000K

protons combined with electrons to form neutralprotons combined with electrons to form neutral

hydrogenhydrogen recombination is sudden.recombination is sudden.

this is the “surface of last scattering”

0 Big Bang

10-38 sinflation

plasmaepoch

379 000yearsrecombination

plasmaepoch

400 000yr

recombination

10-38 s

inflation


History of the UniverseHistory of the UniverseLarge Scale Structure Formation EpochLarge Scale Structure Formation Epoch

Matter collapses under gravity to form the richMatter collapses under gravity to form the richstructure (including us!) of the universe.structure (including us!) of the universe.

photons are (almost!) unaffectedphotons are (almost!) unaffected

Why the difference between Matter & Radiation now?? Why the difference between Matter & Radiation now?? radiation pressureradiation pressure resists the pull of gravity.resists the pull of gravity.

plasmaepoch

400 000yrrecombination

LSSepoch

10-38 sinflation





NOWNOW

t~ 13 700 002 006 years ABBt~ 13 700 002 006 years ABB

T= 2.7 K (T= 2.7 K (--27027000 C)C)

plasmaepoch

400 000yrrecombination

LSSepoch

13.7 GyearsNOW

End of the line for a preciousfew of the photons, as we trapthem in our detectors and gleana little information about theuniverse in which we live.

10-38 sinflation


The Cosmic MicrowaveThe Cosmic MicrowaveBackground RadiationBackground Radiation


Cosmic Microwave BackgroundCosmic Microwave Background

C o b e 1 9 9 2

C o b e 1 9 9 2

C o b e 1 9 9 2

W M A P 2 0 0 3

Dipole Anisotropy 10-3

Large Scale Temp Anisotropy, 10-5


f r o m :

F e b ’ 0 3 A

P S N e

w s

S. C o u

t u




The TeamThe Team

Kevin

EricTrevor

James

Rajat

Claire

Big Blue

( Kareem )

John

Yoshi

( Robert )

the APEXthe APEX --SZ Experimen tSZ Experimen tU.C. Berkeley / LBNLU.C. Berkeley / LBNLHsiaoHsiao--Mei ChoMei Cho

Bill HolzapfelBill Holzapfel

ZigmundZigmund KermishKermish

RuedigerRuediger KneisslKneissl

Adrian Lee Adrian Lee

Martin LuekerMartin Lueker

Jared Jared MehlMehl

Tom Tom PlaggePlagge

Paul RichardsPaul Richards

DanDan SchwanSchwan

HelmuthHelmuth SpielerSpieler

Martin WhiteMartin White

C.U. BoulderC.U. BoulderNils HalversonNils Halverson

McGill UniversityMcGill UniversityMatt DobbsMatt Dobbs

Trevor Lanting Trevor Lanting

Max Planck Max Planck IfR IfR , Bonn, BonnKaustuv Kaustuv BasuBasu

Frank BertoldiFrank BertoldiRolf GuestenRolf GuestenErnst KreysaErnst Kreysa

Karl MentenKarl MentenDirk MudersDirk MudersPeterPeter SchilkeSchilke

Cardiff Cardiff Peter AdePeter Ade


CMB photons are used to backlight structure in the universe.CMB photons are used to backlight structure in the universe.

11--2% of CMB photons2% of CMB photons

traversing galaxytraversing galaxy

clusters areclusters are

inverse Comptoninverse Compton

scattered to higherscattered to higher

energyenergy–– thethe Sunyaev Sunyaev

Zeldovich Effect Zeldovich Effect ..

Tool for mapping expansion historyTool for mapping expansion history

Galaxy cluster searchesGalaxy cluster searches

BIMA

Diabolo

SuZIE

FREQUENCYFREQUENCY


Galaxy cluster searchesGalaxy cluster searches

optical / X optical / X --ray ray sky sky clustersclusters fade away at high redshift.fade away at high redshift.

SZ observations do not fade away over large distancesSZ observations do not fade away over large distances

Clusters can be seen at any distance.Clusters can be seen at any distance.

Carlstrom et al.




Chile

N


Volcan

Licancabu

BOLIVIACHILE

APEX-SZ

LagoVerde

N [email protected]– Oct 27, 2006

LagoVerdeVolcan

Licancabu

APEX-SZ

BOLIVIA

CHILE

San Pedrode Atacama

N




APEXAPEX--SZSZ

320 element TES bolometer array 320 element TES bolometer array

pulse tube cooler w/pulse tube cooler w/ 33He sorptionHe sorptionfridgefridge

MHz biased bolometers +MHz biased bolometers +multiplexing multiplexing

Telescope: 12m Telescope: 12m CassegrainCassegrain, ALMA, ALMAprototype built by Vertexprototype built by Vertex

ChajnantorChajnantor site, 5100msite, 5100m Atacama Plateau, Chile Atacama Plateau, Chile

First light, Dec 2005First light, Dec 2005

1’ resolution at 2mm1’ resolution at 2mm(under(under--filled primary)filled primary)

0.4 degree FOV 0.4 degree FOV


Building a CMB TelescopeBuilding a CMB Telescope

The Night Sky

C o l d E

l e c t r o n

i c s

R e a d o

u t S y

s t e m

300 mK

[email protected]– Oct 27, 2006 [email protected]– Oct 27, 2006

SZ Camera Installed Dec 13SZ Camera Installed Dec 13




APEXAPEX--SZ Readout SystemSZ Readout System

Readout Create with Osc/Demod boards

SZ Camera with SQUID Controllers


APEXAPEX--SZ Field TeamSZ Field Team



[email protected]– Oct 27, 2006 [email protected]– Oct 27, 2006Plot courtesy of Nils Halverson, CU Boulder

Dec 24, 2005

Several Minutes of APEX-SZ Data38 TES Bolometers biased with MHz carriers andcooled without expendable cryogens


S outh Pole T elescopeouth Pole T elescope

10m off axis Gregory telescope10m off axis Gregory telescope

1 deg 1 deg FoV FoV , 1, 1 arcminarcmin beam atbeam at2mm2mm

1000 element bolometer array 1000 element bolometer array frequency domain multiplexedfrequency domain multiplexed

readoutreadout

deploy to pole January 2007deploy to pole January 2007

factor 10 faster mapping speedfactor 10 faster mapping speedthan APEX than APEX 4000 deg 4000 deg 22 at 10 µK/pixelat 10 µK/pixel→→ ~10~1044 clustersclusters

U. Chicago, UC Berkeley, Case Western R., CU Boulder, U.

Illinois, LBNL, McGill, Harvard SAO


S outh Pole T elescope (S PT )outh Pole T elescope (S PT )

Dec 11, 2005




One of the primary challengesfor CMB observations is trying tosee the tiny 2.7 K sky temperaturewhile you’re looking through awarm (300 K) atmosphere, with clouds

and other changing conditions.

This has driven scientists to put theirtelescopes as high as possible—on board high altitude balloons,U2 spy airplanes, and on satellites.

BalloonBalloon--Borne InstrumentsBorne InstrumentsThe Maxima Balloon Payload.

The Boomerang Balloon at the South Pole.


55 element wedge

4 mm

Spider web TES bolometer

Ti

Au

Al

54μm

54μm

64mm

TES Bolometer ArrayTES Bolometer Array

G ~ 400 pW/K τ ~ 7-9 ms


Readout SystemReadout System

fMUX Chip

DDS Oscillators

R B

R1

R 2

-V 2

V 1

I

I 1

RS

C 1 C 2 C 3 C n

L1 L 2 L 3 L n

2

Σ V n(f n )

Demodulator

RS RS RS

R fb

ADCSQUID Controller

TES Bolometers

Series ArraySQUIDs





Special thanks to the staff that make things happen at

McGill:• John and Robert, who have put together a first rate lab andmade it happen fast.• Eddie and Steve, who always tell me it’s nearly impossible tobuild, then build it.• Diane (who’s fighting the overhead monster with me)• Sonia (who’s helping build our next electronics board)• Elizabeth, Louise, and Paula, who make everything happen.

• Nick and Eric (borrowed from UdM), who are building thenext generation.

matt dobbs- probing the opposite ends of time with the cosmic microwave background radiation

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