Theoretical Cosmology and Theoretical Cosmology and Particle Astrophysics at Particle Astrophysics at

CaltechCaltech

Marc KamionkowskiAugust 10, 2005

Astronomy/Astrophysics at Caltech:

Also, SIRTF, GALEX, Hershel..... and everything at JPL. And Carnegie Observatories down the road....

Caltech/JPL will be US center for experimental early-

Universe cosmology over next decade

• Caltech faculty: Readhead, Lange, Zmuidzinas, Golwala

• Boomerang was first experiment to map acoustic peaks in CMB

• CBI was first to measure power on smaller scales• Have vigorous ongoing ground/balloon-based

programs (BICEP, QUaD, QUIET, B2K, CBI, ACBAR, JAKNIFE….)

• Are US PI institution for Planck LFI and HFI, and will have US Planck data analysis center

Theoretical Astrophysics and Relativity:

Thorne, Sari, Phinney, Goldreich (part)

stellar astrophysics, relativity, gravitationalwaves, cosmology, high-energyastrophysics....

Strong postdoc program (Narayan, Tremaine, Bildsten, Hogan....)

Cosmology/ Particle/Nuclear Astrophysics Physics

•Dark matter•Dark energy•Inflation•Neutrino astrophysics•Ultrahigh-energy cosmic rays•Baryogenesis

People now (at least loosely) affiliated with Caltech

theoretical cosmology and particle astrophysics

Postdocs/SRFs:• Asantha Cooray (Sherman

Fairchild Senior Research Fellow; DoE research expenses)

• Milos Milosavljevic (Fairchild Fellow)

• Steven Furlanetto (DuBridge Fellow; ~20% Task B

• L. Arielle Phillips (Irvine Fellow)• Nicole Bell (Fairchild Fellow)• James Taylor (supported by R.

Ellis)• Stefano Profumo (arrives this fall;

~60% Task B)

People now (at least loosely) affiliated with Caltech

theoretical cosmology and particle astrophysics

Graduate Students:• Mike Kesden (NASA GSRP ->

CITA)• Nevin Weinberg (NASA ATP ->

KITP, Berkeley)• Kris Sigurdson (NSERC/DoE->

IAS/Hubble Fellow)• Jonathon Pritchard (TA/DoE)• Tristan Smith (NSF Fellow)• Anthony Pullen (NSF Fellow)• Adrienne Erickcek (NSF Fellow)• Dan Grin (Moore Fellow)

People now (at least loosely) affiliated with Caltech

theoretical cosmology and particle astrophysics

Other Researchers:

• Kris Gorski (JPL Visiting associate)

• Elena Pierpaoli (senior research fellow supported by NSF ADVANCE fellowship)

• Andrew Benson (Moore SRF; to arrive spring 2006)

Visitors:• Robert Caldwell (will visit this

fall from Dartmouth)• Tsvi Piran (Moore

distinguished scholar; 2004-5)

Some Recent Alumni

Students:

• Mike Santos (PhD 2003; now postdoc at Cambridge)

• Catherine Cress (PhD 1999; (Columbia) Natal faculty)

• Alexandre Refregier (PhD 1998 (Columbia); CNRS faculty)

• Xuelei Chen (PhD 1999 (Columbia) KITP postdoc)

Postdocs:• Piero Ullio (1999-2000; SISSA

faculty)• Ken Nollett (2000-2002;

permanent member, Argonne nuclear theory group)

• Peng Oh (2000-2003; UCSB faculty)

• Andrew Benson (2000-2003; Roy Soc advanced fellow)

• Eric Agol (2000-2003; Washington faculty)

Caltech is building in particle astrophysics:

Experiment:

Added Sunil Golwala (dark matter, dark energy, CMB) to faculty 2003

Theory:

Are searching for junior theorist

“Heart of Darkness” initiative will seek private fundingfor theoretical activity at string/particle/cosmology interface

Our recent (~year) research topics

• Effects of dark-matter dipole moments, decays…• Variable fine-structure constant• Probes of dark matter at Galactic center• Dark energy, phantom energy, “Big Rip”• Galactic-halo merger rates• CMB tests of inflation• “Cooling” problem in galaxy clusters• Intergalactic medium• Supersymmetric dark matter• Large-scale structure, weak lensing, inflation, and dark energy• The first stars and reionization

~100 refereed publications over past 5 years

Our work is relevant for• SNAP/JDEM• CMB experiments (WMAP, Planck, CMBPOL…• GLAST/VERITAS/STACEE/….• Collider experiments (to some extent)• Neutrino experiments• CDMS, etc.• Super-K, IceCube….• LSST• SDSS/2dF….• AMS….

Benefits of this program to DoE

• DoE funding heavily leveraged by Caltech• Maintains theoretical activity at major center for

experimental particle astrophysics and early-Universe cosmology

• Supports training of some of the best postdocs and students in the field

• Grad student support goes only to students in final year of research, when they are most productive

• “One-professor” budget supports theory program in exciting emerging area that competes with programs with larger faculty numbers

Funding profile• 1999-2003: ~$100K/year (PI summer salary plus

student)• 2003-2004: ~$150K/year (PI summer salary,

student, plus 2nd student or 50% postdoc)• 2004-2005; ~$140K/year• Current request: continued funding at current

level

Eventually, would like to be able to support 100% postdoc plus student from this Task.

Journal articles completed over past 12 months

under Task B“Pair Correlations and Merger Bias,” Steven R. Furlanetto and Marc Kamionkowski, astro-ph/0507650.

“Dynamical Friction and Cooling Flows in Galaxy Clusters,” Woong-Tae Kim, Amr El-Zant, and Marc Kamionkowski, astro-ph/0506579.

“Direct Detection of the Inflationary Gravitational-Wave Background,” Tristan L. Smith, Marc Kamionkowski, and Asantha Cooray, astro-ph/0506422

``A Running Spectral Index in Supersymmetric Dark-Matter Models with Quasi-Stable Charged Particles,'' Stefano Profumo, Kris Sigurdson, Piero Ullio, and Marc Kamionkowski, Phys. Rev. D 71, 023518 (2005).

``Highly-Ionized Oxygen Absorbers in the Intergalactic Medium,'' Steven R. Furlanetto, L. Arielle Phillips, and Marc Kamionkowski, MNRAS} 359, 295--307 (2005). ``Cosmic Microwave Background Fluctuations from Gravitational Waves: An Analytic Approach,'' Jonathon R. Pritchard and Marc Kamionkowski, Ann. Phys. 318, 2 (2005).

``Cosmic Shear of the Microwave Background: The Curl Diagnostic,'' Asantha Cooray, Marc Kamionkowski, and Robert R. Caldwell, Phys. Rev. D 71, 123527 (2005).

``The Kinetic Sunyaev-Zel'dovich Effect from Reionization'' Matthew McQuinn, Steven R. Furlanetto, Lars Hernquist, Oliver Zahn, and Matias Zaldarriaga, astro-ph/0504189. Submitted to ApJ.

``Is Double Reionization Physically Plausible?'' Steven R. Furlanetto and Abraham Loeb, astro-ph/0409656.

``Polarization Signals of the 21 cm Background from the Era of Reionization'' Asantha Cooray and Steven R. Furlanetto, MNRAS 359, L47 (2005).

``Ly-alpha Emission from Structure Formation'' Steven R. Furlanetto, Joop Schaye, Volker Springel, and Lars Hernquist, ApJ 622, 7 (2005).

``How Universal is the Gunn-Peterson Trough at z~6?: A Closer Look at the Quasar SDSS J1148+5251'' S. Peng Oh and Steven R. Furlanetto, ApJL 620, L9 (2005).

``The Temperature Structure of the Warm-Hot Intergalactic Medium'' Naoki Yoshida, Steven R. Furlanetto, and Lars Hernquist, ApJL 619, L91 (2005).

``Constraining the Topology of Reionization Through Ly-alpha Absorption'' Steven R. Furlanetto, Lars Hernquist, and Matias Zaldarriaga, MNRAS 354, 695 (2004).

``What is L*?: Anatomy of the Galaxy Luminosity Function,'' Asantha Cooray and Milos Milosavljevic, astro-ph/0504580.

``An indirect limit on the amplitude of primordial Gravitational Wave Background from CMB-Galaxy Cross Correlation,'' Asantha Cooray, P. S. Corasaniti, T. Giannantonio, and A. Melchiorri, astro-ph/0504290.

``Dissipationless Merging and the Assembly of Central Galaxies,'' Asantha Cooray and Milos Milosavljevic, astro-ph/0503596.

``Cosmic 21-cm Delensing of Microwave Background Polarization and the Minimum Detectable Energy Scale of Inflation,'' Kris Sigurdson and Asantha Cooray, astro-ph/0502549. Submitted to Phys. Rev. Lett.

``Can LISA Resolve Distance to the Large Magellanic Cloud?'' Asantha Cooray and Naoki Seto, Astrophys.J 623, L113--L116 (2005).

``Cosmological Constraints on the Very Low Frequency Gravitational-Wave Background Authors,'' Naoki Seto and Asantha Cooray, astro-ph/0502054.

``Large-Scale Non-Gaussianities in the 21 cm Background Anisotropies From the Era of Reionization,'' Asantha Cooray, astro-ph/0411430.

``Multifrequency analysis of 21 cm fluctuations from the Era of Reionization,'' Mario G. Santos, Asantha Cooray and Lloyd Knox,'' astro-ph/0408515.

``Gravitational Wave Background of Neutron Star-White Dwarf Binaries,'' Asantha Cooray, MNRAS 354, 25--30 (2004).

``Cross-Correlation Studies between CMB Temperature Anisotropies and 21 cm Fluctuations,'' Asantha Cooray, Phys. Rev. D 70, 063509 (2004).

``Search for Small-Mass Black Hole Dark Matter with Space-Based Gravitational Wave Detectors,'' Naoki Seto and Asantha Cooray, Phys. Rev. D 70, 063512 (2004).

``First Sources in Infrared Light: Stars, Supernovae and Miniquasars,'' Asantha Cooray and Naoki Yoshida, MNRAS 351, L71--L77 (2004).

``Uncorrelated Estimates of Dark Energy Evolution,'' Dragan Huterer and Asantha Cooray Phys. Rev. D 7, 023506 (2005).

Inflationary Gravitational Waves, CMB Polarization, and Direct Detection

NASA COBE map of CMB temperature (1991-

1994)

BOOMERanG map of CMB (2000)

Pre-WMAP bolometer-based measurements:BOOMERanG, ARCHEOPS, ACBAR

BOOMERanG (2002)

Universe is flat; structure grows from primordial adiabatic perturbations

INFLATION

GEOMETRY SMOOTHNESS STRUCTUREFORMATION

WHATNEXT???

Caldwell, MK, Wadley

History of the universe (to scale!)

here be dragons

end of inflationt = 1e-35 sec

EW symmetry breakingt = 1e-12 sec

dark matter decouplingt = 1e-10 sec

quark-hadron transitiont = 1e-5 sec

neutrinodecoupling

t = 1 sec

electron-positronannihilation

t = 5 sec

BBNt = 3 min

matter-rad.equality

t = 56 kyr

formation of CMBt = 400 kyr

reionizationt = 0.2 gyr

matter-lambdaequalityt = 9.5 gyr

you are heret = 13.7 gyr

EM opaqueTransparent to GWs

(from H. C. Chiang)

INFLATION

GEOMETRY SMOOTHNESS STRUCTUREFORMATION

What is Einfl?

STOCHASTIC GRAVITATIONAL WAVEBACKGROUND with amplitude Einfl

2

Detection of gravitational waves with CMB polarization

Temperature map:

Polarization Map:

Density perturbations have no handedness”so they cannot produce a polarization with a curlGravitational waves do have a handedness, so theycan (and do) produce a curl

Model-independent probe of gravitational waves!

(MK, Kosowsky, Stebbins, 1996; Seljak & Zaldarriaga 1996)

No Gravity Waves

Gravity Waves

Direct Detection of Inflationary Gravitational

Waves?(T. L. Smith, MK, Cooray, astro-ph/0506422)

Mission concept studies:

•NASA: Big-Bang Observer (BBO)•Japan: Deci-Hertz Gravitational-Wave Observatory (DECIGO)

seek to detect directly inflationary gravitational-wave background at ~0.1-Hz frequencies

“power-law” “chaotic”

“hybrid”

“symmetry-breaking”

Survey some “toy” models for inflation:

Tens

or-to

-sca

lar r

atio

r

Power-law

chaotic

Symmetrybreaking

chaotic

Other possibilities?· Phantom energy (w<-1) driven inflation

(Baldi, Finelli, Matarrese 2005)· Pre-big-bang, cyclic, and ekpyrotic models

may produce “blue” GW spectra: larger direct signal, without increasing CMB signal

Conclusions· IGWB is detectable in many inflation

models· IGWB probably not directly detectable if

does not show up in CMB polarization· Large lever arm between CMB and

BBO/DECIGO scales provides unique probe of inflationary models