Age 10 36 sec 380 Kyr 1 Myr 13.8 Gyr Inflation reconbination Dark age Begin of universe reionization Big bang CMB First star Foregronds Today Galaxies History of The Universe 2 Standard cosmology model ？ ？ Inflation potential × GeV V 1/4 ≈ /4 r Parameterized with “ r “ : tensor-scalar ratio (T/S) Energy scale of inflation Standard Model ？ ？ Grand Unified Theory GUT scale GeV Planck scale Happen to be same order !?
Targets of QUIET Model predictions of B-modes from the inflation E-modes l(l+1)C l /2 (uK 2 ) Lensing B-modes Primordial B-modes “Inflationary B-modes” QUIET 0.2° 〜 7° 3 Wide multipole range should be covered for ``Inflationary B-modes’’
Toward Inflationary B modes Good systematic error control – Inflationary BB power is less than 1/1,000,000 of TT, 1/10~1/100 or less of EE – Understanding of Foregrounds – Mitigation of experimental systematics Large fields observation – Inflationary BB is significant more than 1 o scale – Should be free from experimental 1/f noise QUIET is designed to fulfill these requirements 4
The QUIET Collaboration 5 countries, 14 institutes, ~50 scientists QUIET observation: Oct – Dec at Atacama, Chile (5,080m) 5
Observation Patches 4 CMB patches were chosen (~3% of full sky) Galaxy observation when CMB patches are not visible 6 ~20 o Visible region along earth rotation QUIET (43 GHz) WMAP (5-year) Stokes, Q Stokes, U Thus far useful for demonstration
Double Mod. D1 D3 D2 D4 QQ UU UU QQ Phase switch phase flip modulation ( 4kHz & 50Hz ) QUIET’s detector L R 11 11 gAgA gBgB Septum polarizer LNA (HEMT) 180 Coupler (±1) 90 Coupler (±i) Simultaneous detection of Stokes Q and U ！ Tiny spurious polarization Imperfection of waveguide components makes tiny fake-pol. However, it doesn’t fluctuate, i.e., could be calibrated very well Precise polarization angle = ½ tan -1 (U/Q) ½ tan -1 (D3/D1) Stable ! No fluctuation !! 12 CMB D1 g A g B × Q D2 g A g B × U D3 g A g B × U D4 g A g B × Q Each diode response g A, g B Responsivity of LNA
Very small 1/f knee 13 Observing data under Chilean sky f knee << f scan Double demodulation suppressed 1/f noise !!
Very small 1/f knee 14 Scan freq. Noise property of experiment E-modes B-modes Measurement range QUIET is free from effects of 1/f noise !!
Tiny spurious polarization Median of all channels (95 GHz band): 0.2% ±0.2% (syst. error dominant) Calibration was scheduled every a few hours (~0.3% precision for each) 15 Total power response as a function of time We also performed cross calibration by using astronomical objects, e.g., Jupiter II Elevation nods QQ
Angle calibration: TauA x sparse-wires (cross check for relative) Absolute Relative (cross check for absolute) angle: 0.5deg (catalog uncertainty is 0.2deg) 16 Q U Taurus T pol. = 5mK, α sky =149.9±0.2° Orientation of sinusoidal curve determines detector angle Yellow bar: precision of single calibration Measured angle of ``standard detectors’’ calibration everyday unless it was invisible No angle fluctuation !!
17 (cross check for relative) Absolute Relative (cross check for absolute) Angle calibration: TauA x sparse-wires Artificial calibrator, ``sparse wires’’ determined relative angles Systematic error for relative angle: 0.8 o
Analysis Strategy Calibration, Data Selection Filter / Map Making B-mode, E-mode spectra Validation Tests 18 Stokes Q map Stokes U map Multipole l (=180 o / ) E-modes B-modes This is simulation
Blind Analysis Framework Validation Tests Analysis Strategy Calibration, Data Selection Filter / Map Making B-mode, E-mode spectra Systematic Error Check 19 “Robust” ✓ ✓ “Box Open” Un-blinding the results
Analysis Validation: Null Tests Divide data set into two maps, difference them. Calculate “null” power spectrum Perform 42 data divisions for 43 GHz (32 divisions for 95 GHz receiver) – Q vs. U channels – weather conditions – cryostat temperature 20 (CMB+Noise A ) - (CMB+Noise B ) (Noise A -Noise B ) Null Power Spectrum
Passed null tests ? YES ! No bias was detected ! – Zero-consistent mean shift ±0.02 (-0.02±0.02) for 43 GHz (95 GHz) – Distribution is consistent with MC validation of statistical error ● data ー MC w/o any systematics Bias estimator : = C l / l 43 GHz band receiver Mean shifts bias detection Width statistical error validation
``Far-sidelobes’’ induced ground pickup GHz observation 95 GHz observation UGS solves Far-sidelobes Characterized by using the Sun 43 GHz receiver 95 GHz receiver One of the source of detected bias by the validation tests
Remove effects of ground pickup by far-sidelobes 23 x 6 different angles Take cross-correlation 10 divisions for Azimuth X 6 divisions of boresight rotations Motion of each patch
QUIET’s E-modes 24 Two independent analysis pipeline obtained consistent results. (Calibrations are not common partially) 43 GHz band receiver 95 GHz band receiver
QUIET’s B-modes GHz band receiver 95 GHz band receiver Zero-consistent power observed
Upper limit for B-modes Upper bounds at 95% C.L. 43 GHz band: r < GHz band: r <
Systematic error for B modes The smallest syst. error to date: δr<0.01 Major inflation models could be covered with large statistics 27
Real data shows “Foreground receiver” is important !! Good estimator for effects of Synchrotron radiation 28 WMAP 30GHz QUIET 43GHz (~1/3 of EE from CDM) One of four patches (CMB-1) at 1 st bin ( l =25–75) = –3.1 for extrapolation Foreground receiver did its task r = 0.02 F.G. for E-modes F.G. for B-modes QUIET(43GHz) WMAP(30GHz) cross-correlation QUIET 95GHz
Summary QUIET’s target: B-modes from the inflation –Designed to minimize systematics Having Foreground receiver Very good systematic error control –Very low 1/f noise First experiment Japanese institution joined One of the best CMB polarization spectrum measurements to date. –In particular E modes “spectrum” –The lowest systematic error to date: r < 0.01 Published papers Results with 43 GHz receiver: ApJ, 741, 111 (2011). Results with 95 GHz receiver: ApJ, 760, 145 (2013). About Instruments: ApJ, 768, 9 (2013). 29
30 Referee report for 95 GHz receiver results Let me congratulate the QUIET team for this impressive piece of work! The control of all systematics down to r of 0.01 is absolutely spectacular. I found the paper clearly written, and a model for future polarization based CMB papers…