Litebird a Small Satellite for the Studies of B-Mode Polarization and Inflation from Cosmic Background Radiation Detection

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LiteBIRD A Small Satellite for the Studies of B-mode Polarization and Inflation from Cosmic Background Radiation Detection

Masashi Hazumi Institute of Particle and Nuclear Studies High Energy Research Accelerator Organization (KEK) Tsukuba, Japan

On behalf of the LiteBIRD working group

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 1 My background POLARBEAR

- from particle physics to experimental cosmology 2007: KEK CMB Group 2012: Now officially established

2005: my “cosmic survey” à chose CMB !

1994-2008: B Factory at KEK QUIET Discovered CP violation in B decays à Kobayashi-Maskawa Nobel 2008 KEK CMB group as of 2012 u ~30 members incl. supporting staffs u Two features http://www.nobelprize.org/ u Bringing HEP-based technologies to experimental

nobel_prizes/physics/ Cosmology (RF, cryogenics, electronics, computing etc.) u International collaborations

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 2 1. Introduction

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 3 LiteBIRD roadmap

POLARBEAR2 LiteBIRD POLARBEAR

GroundBIRD

Ø Ground-based projects as important steps Ø Verification of key technologies for LiteBIRD Ø Good scientific results Ø International projects QUIET 2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 4 POLARBEAR (led by UC Berkeley) Ø 150 GHz TES bolometer array (1274 TESes) w/ 8 MUX Ø Deployment started in Atacama in 2011 Ø First light in Jan 2012 Jupiter

3.5m

TauA

UC Berkeley, UCSD, KEK, McGill, Austin, Cardiff, Colorado, Dalhousie, Imperial C., LAC, LBNL 2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 5 POLARBEAR2 receiver system (led by KEK) 90+150GHz Overview(Focal plane cryostat at the beginning +Optical cryostat) Pulse-tube cooler will add 220GHz later Sorption cooler (3stage: 4He+3He+3He) Antenna- coupled TES array (φ380mm)

ADR(for upgrade)

Ø Deployment in 2014 (Tbath 250mK à 100mK) Main cryostat at KEK Ø End-to-end demonstrations of Ø Large multi-chroic TES array (7588 TESes) Ø ADR (Tbath = 100mK) Ø Wide-band AR coating Ø Wide-band HWP w/ continuous rotation Ø More information on systematics and foregrounds 2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 6 GroundBIRD Ø Cold mirrors Ø Rotary joint Ø Good cryogenic stability MKID Ø Sparse wire grid for TES absolute angle cal.

Ø Spinning telescope (20rpm) à atmospheric noise suppression Ø Access to low-l (fsky=30%) Ø Test-bench for LiteBIRD technologies Ø Initial deployment in Japan in 2014, then to Atacama 2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 7 • Talks and posters on POLARBEAR, POLARBEAR2 and GroundBIRD will be given at the SPIE conference in Amsterdam next week.

• More details and new pieces of information will be shown there.

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 8 How LiteBIRD was started

• Suggestions by JAXA people to apply for the small satellite program in 2008

• Ideas for a small satellite to study CMB B-mode – Warm launch (SPICA technology) – Multi-chroic focal plane (Berkeley technology) – Small mirrors • Proposal to form an official working group under JAXA in Sep. 2008 à accepted !

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 9 LiteBIRD working group

JAXA engineers and Mission Design Support Group

X-ray astrophysicists CMB experimenters (JAXA) (Berkeley, KEK, McGill)

Superconducting sensor Developers (Berkeley, Infrared astronomers RIKEN, NAOJ, Okayama,

(JAXA) KEK etc.)

v More than 50 members v International and interdisciplinary

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 10 LiteBIRD member list

• Y. Takei, H. Fuke, H. Matsuhara, K. Mitsuda, N. Yamazaki, T. Yoshida, S. Sakai （ISAS/JAXA）, • K. Shinozaki, Y. Sato, H. Sugita, K. Yotsumoto, I. Kawano, A. Noda （ARD/JAXA）, • H. Ishino, A. Kibayashi, S. Mima, Y. Mibe (Okayama U.), • A. Ghribi、W. Holzapfel、A. Lee、 H. Nishino、P. Richards、A. Suzuki、(UC Berkeley）, Julian Borrill (LBNL), • I. Ohta(Kinki U.), • M. Yoshida, K. Ishidoshiro, N. Katayama, N. Sato, O. Tajima, Y. Chinone, M. Nagai, R. Nagata, M. Hazumi (PI), K. Hattori, M. Hasegawa, T. Matsumura, H. Morii , N. Kimura, T. Suzuki, T. Tomaru （KEK）, • Y. Inoue, A. Shimizu, H. Watanabe(SOKENDAI), • S. Takada(Tsukuba U.), • E. Komatsu（UT Austin）, • Y. Uzawa, Y. Sekimoto, T. Noguchi（ATC/NAOJ）, • M. Hattori（Tohoku U.）, • M. Dobbs (McGill U.), • K. Natsume, Y. Takagi, S. Nakamura, S. Murayama(Yokohama Nationar U.), • K. Koga, C. Otani (RIKEN) • Supervisors: H. Kodama (KEK), T. Nakagawa (JAXA), R. Kawabe (NAOJ)

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 11 LiteBIRD overview

Ø Full success = The total error on r < 0.001 Ø Observing time > 2 years Ø LEO ~500km or L2 Ø Launch in ~2020 with JAXA’s Epsilon (LEO) or H2 (L2) rocket Ø High Energy Physics (HEP) oriented Ø International collaboration from the beginning Ø Three key technologies Ø Multi-chroic focal plane Ø JT/ST/ADR cooling chain Ø Small (~60cm) cold mirrors (4K)

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 12 2. Mission and system

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 13 LiteBIRD mission • Check representative inflationary models • requirement on the uncertainty on r （stat. ⊕ syst. ⊕ foreground ⊕ lensing) δr < 0.001

No lose theorem of LiteBIRD

Ø Many inflationary models predict r>0.01 à >10sigma discovery Ø Representative inflationary models (single-large-field slow-roll models) have a lower bound on r, r>0.002, from Lyth relation. Ø no gravitational wave detection at LiteBIRD à exclude representative inflationary models (i.e. r<0.002 @ 95% C.L.) Ø Early indication from ground-based projects à power spectra at LiteBIRD ! Huge impact on cosmology in any case

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 14 Bore sight Spin axis LiteBIRD HWP 2ndary mirror (4K) system Super- conducng Primary Focal mirror overview plane (4K) (100mK)

Cryocoolers (JT/ST + ADR)

Solar panels

Standard bus

Beyond COrE workshop Paris Masashi system for 2012/06/25 Hazumi (KEK) JAXA’s small satellites 15 LiteBIRD optics HWP example 4K Reflective Optics Boresight 30cm

2ndary T. Matsumura, HWP doctoral thesis mirror super-conducting bearing wide-band AR (EBEX) Focal Primary plane Focal plane area mirror

30cm Prototype mirrors

50cm

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 16 Major system requirements

Item Requirements Remarks Orbit LEO (~500km) or L2 Launch vehicle: Epsilon or H2 Observing time > 2 years Weight < 450kg from Epsilon payload requirement Power < 500W from JAXA’s standard bus system Total sensitivity < 3µKarcmin 2µKarcmin as the design goal Angular resolution < 30arcmin for 150GHz descoping requires justification Observing frequencies 50-270 GHz (or wider) ≥ 4 bands 1/f knee (f) × scan rate (R) R/f > 0.06 rpm/mHz (e.g. spec. for the case HWP stops R>1.2rpm for f=20mHz) Telemetry > 10GB/day w/ Planck-type data suppression Modulation/Demodulation HWP rotation > 1Hz HWP = Half Wave Plate Total systematic errors < 18nK2 on CBB (l=2)

These requirements are still subject to modifications in the feasibility studies

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 17 Systems Engineering for LiteBIRD

Statistics Systematics

δr<0.001

Foreground Lensing

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 18 Focal plane requirement

Noise level: goal = 2µK・arcmin To be well below (requirement: < 3µK・arcmin) “lensing floor”

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 19 Foreground removal and observing bands

• Foreground removal à ≥4 bands in 50-270GHz

N. Katayama and E. Komatsu, ApJ 737, 78 (2011) (arXiv:1101.5210)

pixel-based polarized foreground removal （model-independent） very small bias r~0.0006 with 60,100,240GHz (3 bands)

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 20 Expected sensitivity on r

Foreground limited

Foregroundrejection parameter Lensing limited

Cosmic variance limited Foreground limited

Katayama-Komatsu Cosmic variance limited

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 21 Expected sensitivity on r

Foreground limited

Foregroundrejection parameter Lensing limited

Cosmic variance limited Foreground limited

Katayama-Komatsu Cosmic variance limited

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 22 LiteBIRD Band We chose the band locations with the following reasons.

1. Katayama-Komatsu (2010) suggested the range of frequency from 50-270 GHz based on the template subtraction. 2. We want to exclude the CO lines. 3. From the practical consideration like AR coating on a POLARBEAR single wafer module lenslet array, it is reasonable to limit the bandwidth to Δν/ ν=1.

Above three constraints naturally put CO us to the band locations. J1-0 J2-1 J3-2

Bolometers 100GHz Sinuous antenna Large pixel (Δν/ν=1) Small pixel (Δν/ν=1) 150GHz Δν/ν=0.23 per band Δν/ν=0.3 per band

220GHz

60 78 100 143 190 280 Fabricated Triplexer Filter GHz GHz GHz GHz GHz GHz UC Berkeley TES option

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 23 Sensitivity in foreground bands

Recovered r (rin=0.002) Recovered r (rin=0.002) 2 1/(1-α) 1/(1-α)2

- 4 uKarcmin at 100 GHz (CMB channel) - 12 uKarcmin at variable freq (Synch channel2) - 4 uKarcmin at 140 GHz (CMB channel) - 8 uKarcmin at variable freq (Dust channel2)

CO J1-0 J2-1 J3-2

Large pixel (Δν/ν=1) Small pixel (Δν/ν=1) Δν/ν=0.23 per band Δν/ν=0.3 per band

60 78 100 140 190 280 GHz GHz GHz GHz GHz GHz 2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 24 Focal plane sensitivity Integration time = 2 effective years

Tmirror = 4 K No dark bolo is included in the count. Band Pixel size Pixel#/ Bolo#/ Sensitivity # of wafer Sensitivity per band [GHz] [mm] wafer wafer per wafer (total # of [uKarcmin] [uKarcmin] bolo on FP) 60 18 19 38 29 8 10.3 78 18 19 38 18 8 6.4 100 18 19 38 13 8 4.6 Sub total 114 (912) 3.5 140 12 37 74 8.8 5 4.0 190 12 37 74 7.0 5 3.1 280 12 37 74 9.2 5 4.1 Sub total 222 (1110) 2.1 All (2022) 1.8

We limit the total number of detectors as ~2000. The MUX factor of 48 (2W/SQUID) will keep the readout power ~100W. Beyond COrE workshop Paris 2012/06/25 Masashi Hazumi (KEK) 25 Focal plane sensitivity Integration time = 2 effective years

Tmirror = 10 K No dark bolo is included in the count. Band Pixel size Pixel#/ Bolo#/ Sensitivity # of wafer Sensitivity per band [GHz] [mm] wafer wafer per wafer (total # of [uKarcmin] [uKarcmin] bolo on FP) 60 18 19 38 45 8 16.0 78 18 19 38 27 8 9.5 100 18 19 38 17 8 6.0 Sub total 114 (912) 4.8 140 12 37 74 12 5 5.3 190 12 37 74 9 5 4.0 280 12 37 74 11 5 4.5 Sub total 222 (1110) 2.6 All (2022) 2.3

We limit the total number of detectors as ~2000. The MUX factor of 48 (2W/SQUID) will keep the readout power ~100W. Beyond COrE workshop Paris 2012/06/25 Masashi Hazumi (KEK) 26

LiteBIRD focal plane design tri-chroic（140/190/280GHz） UC Berkeley TES option

tri-chroic（60/78/100GHz）

Tbath = 100mK

Beyond COrE workshop Paris 2012/06/25 Masashi Hazumi (KEK) 27

LiteBIRD focal plane design tri-chroic（140/190/280GHz） UC Berkeley TES option

Band centers can also be distributed to increase the effective # of bands

tri-chroic（60/78/100GHz）

Tbath = 100mK

Beyond COrE workshop Paris 2012/06/25 Masashi Hazumi (KEK) More space to place <60GHz detectors 28 TES signal multiplexing Frequency-domain multiplexing (MUX) used in POLARBEAR, SPT, EBEX etc. (8-16 MUX)

toward LiteBIRD

Frequency-domain multiplexing

Replace analog feedback loop with Digital Active Nulling (DAN) to achieve 64 MUX led by McGill University (supported by CSA) Berkeley-KEK-McGill-NIST

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 29 MKID option for higher MUX factor

300 mK stage NAOJ LiteBIRD is currently the guiding force for RIKEN KEK the MKID development in Japan

102 pixel MKID OKAYAMA

Si lens-array

Double slot antenna + Al MKID

Electrical noise measurement M. Naruse et al. 2012

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 30 LiteBIRD thermal design

FP 2-stage Stirling Cooler

• Thermal studies on Precoolers (２ST/JT): A solution w/ reasonable margin (28.8%) • Structure analysis was also OK • 3-stage ADR (32kg): Leak B-field is small enough: less than 0.5Gauss for > 100mm from ADR 2ST/JT BBM

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 31 L2 vs. LEO

3sigma discovery region

L2 case

Katayama-Komatsu 2011 (foregroundrejection parameter)

LEO

L2 σ

Both cases satisfy the requirement on statistical error

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 32 LiteBIRD scan strategy • Started feasibility studies from “EPIC-type” scan – Off-spin-axis boresight and precession • Fast scan (3~6rpm) put large burden on attitude control system as well as start tracking system. – We have not found a good solution while keeping LiteBIRD light. • Now default is continuous HWP rotation (~2Hz) with slower spin rate (~0.1rpm). – Need for ~0.6rpm to achieve minimal success even in case of malfunction of HWP rotation – Requirement on offline pointing knowledge is rather severe (~10arcsec) if we achieve full success w/o HWP. – Demonstration of continuous HWP at POLARBEAR2 is important for us.

2012/06/ Beyond COrE workshop Paris Masashi Hazumi (KEK) 33 25 LiteBIRD scan strategy: LEO case y Spin axis

x Spin axis Boresight Boresight z γ: relative angle betw/n moon and boresight (60 degs) β = 34 degs Anti-sun Satellite α = 76 degs 6000K Anti-sun 175K 300K

altitude 500 km - Spin axis rotation about anti-sun axis

(i.e. satellite period around the earth) fs = 90 min

- Boresight axis rotation about spin axis fb ~ 0.6 rpm 150 Mkm 0.38 Mkm Sun ↔ Earth Earth ↔ Moon scan uniformity cross link

LEO

2012/06/25 Uniformity and cross link nearly as good as those at L2Beyond COrE workshop Paris Masashi Hazumi (KEK) 34 LiteBIRD DAQ・telemetry We need to transfer about 10GB per day.

We assume Planck like data compression (~0.25) on board.

Using the combinations of s- and x-bands, it will take < 1h for LEO and a few hours for L2 to downlink the data. requirements on antenna gain

on-board data compression required, and demonstrated

2012年 10月 13日 using FPGAsT. Matsumura/ACP colloquium 35 Launch vehicle (1): Epsilon

2012/06/ Beyond COrE workshop Paris Masashi Hazumi (KEK) 36 25 SPRINT program With Epsilon rockets**, SPRINT-A “EXCEED”

2 launches/3 years from 2013. launch in 2013

• “Lowering the hurdles to space” • Welcome new challenges

Semi-Made-to-Order satellite

** Use of the Epsilon rocket is not the requirement but is assumed unless otherwise proposed.

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 37 Launch vehicle (2): H2

H2 rockets for medium/large payloads • “ASTRO” series (Suzaku, Akari etc.) • ASTRO-H (X-ray) in 2014, • SPICA is a candidate for an ASTRO mission.

2012/06/ Beyond COrE workshop Paris Masashi Hazumi (KEK) 38 25 3. Project management

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 39 Two opportunities

• SPRINT series (for science or technology) – Launch vehicle: Epsilon – Currently LiteBIRD is a candidate among 12 others – So far LEO only

• ASTRO series (for science) – Launch vehicle: H2A or H2B – Most likely together w/ other satellite(s) – Can go to L2

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 40 Procedure toward launch

• MDR proposal in March 2013 – Choose default orbit, launch vehicle, detector technology – Define risks and keep options as part of risk management • Joint work with JAXA’s Mission Design Support Group (MDSG) is ongoing.

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 41 Support by research communities

• Japanese High Energy Physics (HEP) community has identified CMB polarization and dark energy survey as two important areas of their “cosmic frontier”.

• Japanese radio astronomy community also expressed their support to LiteBIRD.

• Cosmology community (theory) is also supporting LiteBIRD and contributing to the science case.

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 42 Japanese HEP community’s “The Final Report of the Subcommittee on Future Projects of High Energy Physics” 11 February 2012 An excerpt from the “Recommendations” part Some of the medium/small scale projects currently under consideration have the potential to develop into important research fields like neutrino physics in the future and should be promoted in parallel in pursuit of new physics from various directions. Flavor physics experiments such as muon experiments at the J-PARC, searches for dark matter and neutrinoless double beta decays, observations of CMB B-mode polarization and dark energy are considered as projects that have such potential.

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 43 “Cosmic Background Radiation” selected as an “innovative areas for research” by MEXT (our funding agency) • Term: April 2009 – March 2014 • 10 areas selected our of ~200 proposal from all branches of science (except billogy/medicine which are treated separately) • On-going ground-based projects and LiteBIRD R&D are supported by this grant. LiteBIRD

CIB

5 research S. Matsuura (JAXA) groups under Foreground the flag of M. Hattori MKID LiteBIRD (Tohoku) C. Otani (RIKEN) CMB Theory M. Hazumi H. Kodama

2012/06/25 Beyond COrE workshop(KEK) Paris Masashi (KEK)Hazumi (KEK) 44 4. Discussions and conclusion

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 45 Why observation in space ?

• Whole-sky survey required for reionization bump – lensing is subdominant even at r = 0.001

• No atmospheric noise

• No constraint in frequency band selection (except CO lines) – Important to remove foregrounds e.g. V-band never used on ground

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 46 CMB polarization power spectra

47 2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) Why small satellite ?

10° 1° 3sigma discovery ~0.5°angular resolution

region （@150GHz） is sufficient

Mirror diameter ~60cm

LiteBIRD does the job

Ø Less expensive Ø More launch options than a big satellite Ø Better in terms of mirror cooling Ø Yet no compromise on r measurements Ø Ground-based telescopes for supporting measurements

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 48 Delensing with SuperPOLARBEAR

SuperPOLARBEAR assumes 6µKarcmin for f_sky = 0.75 (many small patches)

5σ boundary

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 49 Three key technologies to make LiteBIRD light

• Small mirrors (~60cm) • Warm launch with mechanical coolers • Technology alliance with SPICA (JAXA technology) for pre-cooling (JT/Starling) • Alliance with DIOS (X-ray mission) for ADR • Multi-chroic focal plane

• ~2000 TES (Tbath=100mK, δν/ν ~ 0.3), or equivalent MKIDs • Technology demonstration with ground-based projects (POLARBEAR2, GroundBIRD)

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 50 Conclusion • CMB polarization will be the frontier in post-Planck era – Best probe to discover primordial gravitational waves

– Unique tests of inflation and quantum gravity

• The goal of LiteBIRD is to search for primordial gravitational waves with the sensitivity of δr<0.001, for testing all the representative inflationary models.

• Technology verification in ground-based projects in next ~3 years will be crucial. The LiteBIRD roadmap includes such ground-based projects.

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 51 CMB polarization workshop in Japan

• Tentative date/venue – 9-11 February, 2013 – Okinawa, Japan (a tropical island, very far from Tokyo) date/venue subject to change … let me know if the timing is fine • You are very welcome to join the workshop !

Candidate venue: Okinawa Institute of Science and Technology (OIST, http://www.oist.jp)

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 52 Backup slides

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 53 Angle miscalibration and fake B-mode power

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 54 Discovery potential（>3σ）and model predictions

5 4 3 2 1 LiteBIRD ~2020 Single-field slow-roll w/ ns-r relations Power-law POLARBEAR2 Chaotic p=8 ~2016 SSB (Ne = 47-62) Chaotic p=0.1 String theory examples QUIET2 ~2015 1. N-flation, 2. Axion Monodromy, 3. Monodromy 4. Fiber inflation, 5. Warped POLARBEAR D-brane, Kahler, Racetrack, .. ~2014

Pagano-Cooray-Melchiorri- Bound from Kamionkowski 2008 ~2014 Baumann, arXiv:0907.5424 Lyth relation Planck (0.002) Competition BICEP2, KECK(South pole) 0.0001 0.001 0.01 0.1 1 EBEX, SPIDER(balloon-bourne) ※ statistical and foreground r present upper limit etc. uncertainties taken into （95%C.L.） Both sensitivity and schedule similar to POLARBEAR account

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 55 Scientific Shopping List (space+ground)

• Primordial gravitational wave (low-l B mode) – inflation model selection Cosmology – Tests of quantum gravity, even string theories ! and • Lensing（high-l）B-mode precision measurements Fundamental – neutrino mass, gravitinos etc. Bonus: physics Cross correlations – (early) dark energy w/ other frequencies • Beyond the Standard Model

– parity violation in gravity （non-zero CEB etc.) Astronomy • Cosmic reionization science (low l） • Foreground science Rich and important science from CMB polarization

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 56 Projects in the world

1. Ground 2. Balloon 3. Satellite ACTPol QUIET SPIDER WMAP (obs. end in 2010)

POLARBEAR Atacama, Planck In addition, Chile ABS, CLAS, ... EBEX

S-E Ｌ２ PIPER SPTPol

South Pole In addition, POLAR, ...

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 57 Comparison with laser interferometer - my personal comment

u CMB polarization is much more sensitive than interferometry. u Discovery (on ground or in space) of PGW from CMB polarization will give a specific target for future gravitational wave detection experiments. à a very strong science case can be made.

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 58 Sub-component status

• Optics: – completed a baseline design and fabricated a prototype • Focal plane: – completed a baseline design • Thermal/mechanical design: – preliminary studies and found solutions w/ ~30% margin • Orbit/attitude control: – choose <1rpm (requiring HWP) for feasibility studies • Telemetry: – requirements for L2/LEO obtained • Foreground studies: – δr=0.0006 w/ 3 or more bands in 50-270GHz • Systematics: – Studying requirements to make a systematic error budget

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 59 Cosmic inflation • An accelerating expansion at the very early universe. • The leading hypothesis to answer one of the grand questions in cosmology “what powered the big bang ?” • We can probe the inflationary universe with CMB polarization ! (indeed inflation is the earliest period we can probe with cutting- edge technology) • Underlying quantum gravity theory, which is not yet understood, can also be tested by probing the inflationary universe.

So, how does it work ?

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 60 CMB linear polarization map Probing inflation with CMB polarization telescope spectral analyses Ey

Ex polarization • Ex2 – Ey2 • ExEy

E-mode B-mode

power spectra

Smoking-gun signal of primordial

W. Hu et al. astro-ph/0210096 al. et Hu W. gravitational wave, predicted by inflation theories

Beyond COrE workshop Paris Masashi Hazumi 2012/06/25 CMB B-mode(KEK) is the most sensitive probe for inflation 61 CMB polarization power spectra

Satellite ! E mode Reionization Ground-based large telescopes, neutrino masses, Recombination dark energy

（~ current limit）

Primordial B mode (not yet detected)

Determination of

r (tensor-scalar ratio) Shed light on inflation energy scale62 2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) Physics of inflation

Leading hypothesis = new scalar field “Inflaton” In case of single-field slow-roll inflation (= so-to-speak “standard model Higgs” in cosmology) r (tensor-to-scalar ratio) is a key parameter

Inflation potential proportional to r V1/4 = 1.06 × 1016 × (r/0.01)1/4 GeV Unique probe of GUT scale physics !

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 63 Search for r>0.01 well motivated

Current limit

r > 0.01 favored

Theoretical predictions (including super-string theories in eleven dimensions !)

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 64 Pagano-Cooray-Melchiorri-Kamionkowski 2007 Take-home message

• Current limit r~0.2 • POLARBEAR-2 r~0.01 • LiteBIRD r~0.001

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 65 GroundBIRD’s scan strategy

GroundBIRD: 30% of full sky

QUIET 60 deg (~3%)

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 66 KEK CMB Group History

• Nov. 2007：Established, joined QUIET Low frequencies • Jun. 2008：Joined POLARBEAR • Sep. 2008：Proposed LiteBIRD, WG accepted by JAXA • Mar. 2009：CMB session established at JPS QUIET • Apr. 2009：MEXT Grant-in-Aid started (http://cbr.kek.jp/) High • Oct. 2010：JSPS Brain Circulation program started frequencies • Dec. 2010：Initial results from QUIET • Apr. 2011: CMB B-mode and dark energy selected as two mostPOLARBEAR important cosmic connections by HEP community in Japan Ultimate observations • Aug. 2011: Official support on LiteBIRD from Japanese radio astronomy community • Sep. 2011：POLARBEAR deployment in Chile started LiteBIRD Beyond COrE workshop Paris Masashi 2012/06/25 67 Hazumi (KEK) KEK CMB Group

Various “previous lives” including Belle, SuperK, BESS, gravitational wave detection, sub-mm astronomy, theory.

Also getting strong support from cryogenics center, electronics system group and machine shop at KEK. In total ~30 members

2012/06/25 Beyond COrE workshop Paris Masashi Hazumi (KEK) 68