Pos(ICHEP2012)441

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PoS(ICHEP2012)441 http://pos.sissa.it/ [email protected] The Q/U Imaging ExperimenT (QUIET) is aaim ground-based is CMB to Polarization detect experiment, the whose degree-scalewaves. B-modes (curl components) The induced existence by of primordialand gravitational the hence the primordial detection gravitational of wave the B-modes isThe is B-mode a a signal "smoking-gun" generic is signature expected prediction of to the be ofso inﬂationary orders inﬂation, universe. of a magnitude large smaller than detector the array temperatureQUIET anisotropy with employs precise the control world and largestbands, mitigation coherent and of receiver had arrays systematic accumulated in effectsChajnantor CMB is 43 plateau. data essential. Our GHz unique for and instruments over design 95levels and 8000 GHz of the hours calibration frequency systematic strategy at errors lead to 5,000m to theIn date. altitude lowest this in Those proceedings, advantages Chile: we enable review the us the polarization QUIET measurements. to experiment begin and to report prove the the latest B-modes. results for the CMB Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike Licence. c

36th International Conference on High EnergyJuly Physics, 4-11, 2012 Melbourne, Australia Masaya Hasegawa for the QUIET Collaboration High Energy Accelerator Research Organization, KEK E-mail: CMB Polarization Results from the QUIET Experiment PoS(ICHEP2012)441 , ]. 2 / 1 1 ] for 4 Ks µ and 87 2 / 1 Ks µ 2 ]. In the first observing season, we deployed 17-elements detector 3 ], and here we mainly describe on the measurement of CMB polarization power spectra with The responses of each detector to the polarized signal are calibrated and monitored with reg- The detectors which form the focal planes use a highly compact design based on High Electron The QUIET telescope consists of a 1.4 m side-fed classical Dragonian antenna, which provides The faint pattern of cosmic microwave background (CMB) polarization promises to provide The Q/U Imaging ExperimenT (QUIET) is a ground-based program to measure the CMB 2 ular calibration observation of astronomicalorientations of and the polarization artificial responses) sources. are calibratedof to The Tau-A 0.5 observations detector deg. for precision angles with absolute-angle (i.e., the determination combination the and a sparse-wire-grid calibrator [ which were the best sensitivity among on-going CMB polarization experiments when we deployed. relative-angle determination over the focalness plane. as a source) Sky allows dip us to (usingtotal measure power the the (so-called varying spurious I-to-Q/U polarization atmospheric leakage) of with thick- eachsivities 0.3% detector are precision with calibrated per respect using calibration. to the Tau-A The andstudy detector lead sky-dip respon- to data. the lowest This level calibration of strategies systematic and errors the as will dedicated be discussed in this paper. Mobility Transistors (HEMTs) that provides simultaneousQ, measurements U, of and the I Stokes in parameters a singlearray, detector with [ a central frequencyarray at of a 43 central GHz; frequency of in 95 the GHz. second The sensitivity season of we each observed array with is 69 84-elements the angular resolution of 27 arcmin.is (12 designed arcmin.) to probe at degree 43GHzThe scale (95 telescope angular GHz) also frequency scale has band. at a which The co-movingtelescope the ground-shield optics sit to inflationary suppress B-mode atop sidelobe signature a response. peaks. 3-axis Thethe (azimuth, detector third and elevation, axis and (deck), "deck") wepolarization mount modulated systematic system. errors. the instrumental-polarization By axis, regularly suppressing rotating instrumental- 2. Instrument the 95 GHz data, as well as the instruments and observation. new and interesting information onin the the next universe. decade The is to primarygravitational detect waves. goal the The of degree-scale existence CMB B-modes of (curl polarization theinflation. components) studies primordial induced gravitational Therefore by waves the primordial is a detection generic of prediction the of B-modes is a "smoking-gun" signature of inflation [ CMB Polarization Results from the QUIET Experiment 1. Introduction polarization, and among the experiments aimingscientific for the observation detection was of started the inflationary withof B-modes. the observation, The 43 we GHz deployed detector 95August in GHz 2009 October detector, and replacing 2008. December 43 2010. After GHzin The nine detector, [ first and months science observed result between with 43 GHz data have been published Furthermore, the energy scale of inflationaryB-modes. potential can Therefore, be the reconstructed CMB fromcists, polarization the too. experiment power of is the quite attractive for high energy physi- PoS(ICHEP2012)441 G-2 G-1 CMB-1 sky region. We selected

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from the Sun and Moon throughout the year, which allows uninterrupted 8h ◦ CMB-2 CMB-3 CMB-4 ). Then we modeled the noise in each CES to understand the statistical uncertainty. K µ QUIET sky patches (circles) in equatorial coordinates, plotted over the WMAP Q-band tempera- Our analysis method converted each-detector time-ordered data (TOD) into CMB polarization We observed four patches as shown in Fig. We started scientific observations in October 2008 with the 43 GHz (Q-band) receiver array. The observation site was the Chajnantor Test Facility on the Chajnantor Plateau in the Atacama We filtered the data inWe rejected the data time that domain had tomade too maps remove much by residual contamination. projecting the 1/f Q After noise and this U and processing intensities ground into in Galactic contamination. the coordinates time with taking domain, into we account 4. Analysis power spectra. The analysis flowlarization is ( as follows. First we calibrated the TOD into units of sky po- Figure 1: ture map. the patches for their loware synchrotron separated at emission least as 30 measuredobservations by throughout WMAP, the and season. because thefixed Each patches elevation patch (CES) is for scanned typically with a periodical azimuth motion at elevation and azimuth are thenpatch changed to sets recenter and the another patch, patchwe and is this observe selected. process thought continues a By untilcontribution. the scanning constant at column constant density elevation of for atmosphere each patch and scan, ensure a stable atmospheric The observing season finished in June 2009,the collecting instruments 2668 hours into of the CMB 95 data. GHzDecember Then we 2010, (W-band) switched receiver collecting array, 5337 and hours observed of between CMB August data. 2009 and Desert, Chile. The site is known asof one of its the high best place altitude over (5080 thezenith world m) sky for and measuring brightness CMB low at because atmospheric 95 water GHz (43 vapor. GHz) Under is the about median 5 K conditions, (10 the K). CMB Polarization Results from the QUIET Experiment 3. Observation PoS(ICHEP2012)441 . The possible 4 100, are less than the signal ∼ l ]. QUIET is the first CMB experi- . This is one of the most stringent 7 1 ], and have adopted the same policy for both 8 . Based on these measurements, we constrain , 2 2 4 ]. To calibrate the analysis pipeline and understand its ). Then power-spectrum estimation is performed with 6 2 , ( r < 2.7 at 95% C.L.) 5 9 8 . . 0 0 + − 2 . 1 = r 1 − 800, and three acoustic peaks are clearly traced, while the BB spectra are ∼ l = 0.002 Mpc 0 k cross correlation technique [ QUIET CMB polarization maps of the CMB-1field in Galactic coordinates at 95 GHz. The left l together with the results by different experiments. The EE spectrum is strongly signal- C 3 The systematic errors in the power spectra in W-band are shown in Figure Here, r is defined as the ratio of the primordial-gravitational-wave amplitude to the curvature-perturbation ampli- The measurements of EE and BB power spectra with Q-band and W-band data are plotted in 1 the Q-band and W-band analysis. CMB Polarization Results from the QUIET Experiment the telescope pointing informationpseudo- (Fig. ment to have adopted a strictand blind-analysis finalized, policy, in and which the all systematic data-selectionspectrum. criteria errors This are process are adjusted was assessed described in prior detail to in looking [ at any cosmological power uncertainty, we performed the same analysisWe validated on our hundreds analysis of chain simulations with of a blind-analysis the strategy entire [ experiment. tude at a scale 5.1 Systematic Errors Figure dominated up to the tensor-to-scalar ratio to 5. Results consistent with zero within the estimatedpower statistical and is systematic also uncertainties. visible The in dominant the EE maps shown in Figure Figure 2: (right) panel shows Stokes Q (U),Pole. where the Note polarization the angle coherent isthese vertical/horizontal defined are patterns with the in respect expected to the signature the Qsubtracting of Galactic map, the a North and very pure largest the E-mode angular diagonal signal. scales patterns (ell No in > filtering the 25), has to U been which map; applied QUIET to is this not map sensitive. beyond upper limit to date. contaminations are well below the statisticalmultipole errors; range in relevant particular, for the estimation level of of the spuriousof tensor-to-scalar B-modes r ratio, for = 0.01. This is the lowest level of BB contamination yet reported by any CMB experiment. PoS(ICHEP2012)441 01 at . 0 ∼ r Lensing l CDM model. The polarization data passed all Λ 5 Multipole Moment, r = 0.1 QUIET-W QUIET-Q BICEP BOOMERanG CAPMAP CBI DASI MAXIPOL QUAD QUIET-W QUIET-Q BICEP BOOMERanG CAPMAP CBI DASI MAXIPOL QUAD WMAP 30 100 300 1000 1 1 0 2 0 2 -1 -1 -3 -2

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2 EE BB 2 Summary of CMB polarization EE power spectrum (top) and 95% C.L. upper limits on BB Support for the QUIET instrument and operation comes through the NSF cooperative agree- Motivated by the exciting possibility of detecting the gravitational waves due to inﬂation, many 100. Our observation strategy and analysis frame provide a guide for future experiments in ∼ CMB Polarization Results from the QUIET Experiment l search for the signature inﬂationary gravitational waves in CMB polarization. Acknowledgement ment AST-0506648. Support wasPHY-0551142, PHY-0855887, and also AST-1010016; KAKENHI 20244041, provided 20740158, by and 21111002; PRODEX NSF C90284; awards a PHY-0355328, KIPAC AST-0448909, Enterprisetion grant; of and New by Technologies the (SAINT). Strategicwho We Alliance maintained are and for particularly operated the indebted the telescope: Implementa- to Jose the Cortes, engineers Cristobal Jara, and Freddy technician Munoz, and Carlos 6. Conclusion efforts are underway to develop the instrumentationIn and this methods proceedings, necessary to we search havefrom for presented B-modes. QUIET. the The instrument, EE spectrum observationwith and is zero. measured the with latest The high analysis EE S/N; results spectrum the is BB consistent power with spectrum a is consistent Figure 3: power (bottom) measured by various experiments. of the statistical validation testsof potential before systematic looking errors the indicate power that all spectrum. systematic effects A are detailed below extensive the study level of PoS(ICHEP2012)441 , bf , 111 , 741 Phys. , MNRAS 7741 , ApJ. CDM curve in EB Λ 475 0 200 400 600 800 -1 1 -2 -3 -4 -5 ≤ 10 10 10 10 10 10 l ≤ Proc. SPIE , 25 , 559-584 (2003) 343 , 100. ∼ Primordial (r = 0.20) Primordial (r = 0.01) Lensing l BB 0 200 400 600 800 01 at -1 1 -2 -3 -4 -5 . 10 0 10 10 10 10 10 ∼ 6 r ℓ ℓ ℓ , 145 (2012) 760 , 936 (2011) Fast cosmic microwave background power spectrum estimation of All-sky analysis of polarization in the microwave background Blind Analysis in Nuclear and Particle Physics. Review of Nuclear and 167 I to Q/U Leakage Angle, Relative Responsivity, Pointing Scan-synchronous Signal, Far Sidelobes CDM Absolute Responsivity, Window Function Λ Statistical Error Systematic Errors EE First season QUIET observations: Measurements of Cosmic Microwave Second Season QUIET Observations:Measurements of the CMB Polarization 0 200 400 600 800 -1 1 -2 -3 -4 -5

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ℓ Coherent polarimeter modules for the QUIET experiment 2 Novel Calibration System with Sparse Wires for CMB Polarization Receivers Journal , bf 55, 141-163 (2005) , Fast estimation of polarization power spectra using correlation functions el al. , 1830 (1997) Summary of systematic error assessment for E-modes and B-modes. The red bars indicate the D55 Rev. (2011) G. Chon et al., 350, 914-926 (2004) F. K. Hansen and K. M.temperature Gorski, and polarization with Gabor transforms. MNRAS J. R. Klein and A. Roodman, QUIET Collabolation, Power Spectrum at 95 GHz ApJ. O. Tajima Particle Science M. Zaldarriaga and U. Seljak, QUIET Collaboration, Kieran A. Cleary, Background Polarization Power Spectra at 43 GHz in the multipole range of Low Temperature Physics 77412N (2010) [8] [6] [7] [3] [4] [5] [1] [2] Verdugo. Finally, QUIET was ledservations by were Bruce completed. Winstein, His intellectual who and diedsuccess. scientiﬁc in guidance 2011 was crucial February to soon the after experiment’s ob- References Figure 4: statistical uncertainties in each bin. Blue,atic green, errors: and I-to-Q/U purple leakage; points polarization correspond angleserror; to (absolute and three and the categories residual relative), scan-synchronous of relative signals responsivities system- and and far pointing sidelobes. The gray band along the EE corresponds to the uncertainties of multiplicativeFor factors: BB, absolute all responsivity systematic and errors the are window function. below the level of CMB Polarization Results from the QUIET Experiment