Http: // oberon.roma1.infn.it / boomerang http: // / ~boom.

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1 http: // oberon.roma1.infn.it / boomerang http: // www.physics.ucsb.edu / ~boom

2 The image of the CMB Mapping the CMB is very important, since the properties of the image of the CMB are determined by: 1)The physical processes happening in the early Universe 2)The large scale geometry of the Universe 3)The expansion history of the Universe

3 Long Duration Balloon Flights NASA-National Scientific Balloons Facility (based in Palestine-Texas), provides circum-Antarctic long-duration balloon flights during the Antarctic summer. 37 km for 7-14 days. This enables long integrations, wide sky coverage and extensive tests for systematic effects, through the repetition of measurements under different experimental conditions: Different locations: control ground spillover Different day: control Sun in the far sidelobes day vs nightobservations have different scan directions on the same area, producing crosslinked maps. William Field, McMurdo, Ross-Sea 167 o 5.76E ; 77 o 51.76 S

4 The launch: Dec. 29, 1998

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6 CMB anisotropy results: images of the early Universe

7 The sky scan The image of the sky is obtained by slowly scanning in azimuth (+30 o ) at constant elevation The optimal scan speed is between 1 and 2 deg/s in azimuth The scan center constantly tracks the azimuth of the lowest foreground region Every day we obtain a fully crosslinked map.

8 BOOMERanG: the MAP 1998: BOOMERanG mapped the temperature fluctuations of the CMB at sub-horizon scales (<1 O ). The signal was well above the noise: 2 indep. det. at 150 GHz

9 The next BIG step: CMB polarization measurements Velocity fields in the early Universe

10 The Polarization-sensitive BOOMERanG: B2K BOOMERanG can give an important contribution to CMB polarization research We have modified the focal plane after the anisotropy flight of 1998 to accomodate Polarization Sensitive Bolometers (PSB). We have flown the instrument in Jan. 2003 to detect E-modes We plan to fly it again to detect E and B modes polarization of the foreground from ISD at high galactic latitudes.

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12 06/01/2003

13 BOOM03 Flight 11.7 days of good data Launched: January 6, 2003 From: McMurdo Station, Antarctica

14 Measurements OK for 11.6 days

15 BOOMERanG landed near Dome Fuji (h=3700m) after 14 days of flight. The data have been recovered immediately. The payload has been recovered in Jan 2004.

16 BOOMERANG / B2K Polarization measurements Preliminary results

17 Optimal CMB anoisotropy maps obtained with IGLS, the Rome pipeline (Natoli et al. 2001). The anisotropy signal is much larger than the instrument noise. This is the CMB map with highest S/N ever. For the polarization signal the problem is harder.

18 Rods show measured polarization (signal + noise) Deep region: polarization signal similar to the noise Shallow region: polarization signal smaller than the noise

19 Next BOOMERANG: B2K5 We plan to re-fly B2K with an upgraded focal plane, to go after foreground cirrus dust polarization. This information is essential for all the planned B-modes experiments (e.g. BICEP, Dome-C etc.) and is very difficult to measure from ground. The BOOMERanG optics can host an array of >100 PSB at >350 GHz.

20 30 B2K B2K5 16 detectors 128 detectors

21 Higher resolution images of the early Universe Shading light on the dark ages OLIMPO

22 OLIMPO An arcmin-resolution survey of the sky at mm and sub-mm wavelengths (http://oberon.roma1.infn.it/olimpo) Silvia Masi Dipartimento di Fisica La Sapienza, Roma and the OLIMPO team

23 30 CMB anisotropySZ clustersGalaxies mm-wave sky vs OLIMPO arrays 150 GHz220 GHz340 GHz540 GHz

24 Olimpo: list of Science Goals Sunyaev-Zeldovich effect –Measurement of H o from rich clusters –Cluster counts and detection of early clusters -> parameters () Distant Galaxies – Far IR background –Anisotropy of the FIRB –Cosmic star formation history CMB anisotropy at high multipoles –The damping tail in the power spectrum –Complement interferometers at high frequency Cold dust in the ISM –Pre-stellar objects –Temperature of the Cirrus / Diffuse component

25 OLIMPO (http://oberon.roma1.infn.it/olimpo) Test flight from Trapani (Italy) (July 2005) Long Duration Balloon flight from polar regions (Peterzen et al. ESA Symposium 2003 – St. Gallen)

26 Svalbard LDB tests Test launch July 24, 2004 Feasibility of LDB flight from Svalbard proven More than 40 days at float IRIDIUM telemetry module for OLIMPO succesfully tested Solar panels/charge control tested Forecasted OLIMPO LDB scientific balloon flight in Summer 2006

27 BOOMERANG launch movie (10 min.) Click on the black frame to start

28 Possible Synergies on LDBs Technical subsystems: –Attitude control (ACS) and reconstruction –Power control (solar panels for daylight flights: experience with BOOM and OLIMPO) –Telemetry (Iridium-based global telemetry for moderate data rates: experience with Pegaso – G.Romeo, 2400 bps; new parallel system for higher throughput under development for OLIMPO) Stratospheric background radiance from –Archeops star sensor data –B2K star camera data –Models

29 Il Sistema di Puntamento (Arc min)90GHz ( K)150GHz ( K)240GHz ( K)400GHz ( K) 16256121209 2124112242418 3186168364628 Errore introdotto da un pendolamento della gondola E. Pascale, Nov.2000 Se il puntamento non è preciso, la foto viene sfuocata: si perdono le informazioni a piccola scala

30 Attitude Control System (ACS) Boomerang ha un beam di 10 minuti darco. LACS deve garantire: La ricostruzione della linea di vista entro 1 arc-min rms Sensori di posizione Scansioni in azimut a velocità costante Massimizzare la copertura di cielo Controllare effetti sistematici: Gradienti di temp. sulle strutture Residuo atmosferico Hardware di puntamento Minimizzare i pendolamenti per ridurre il segnale indotto dalla modulazione dellatmosfera E. Pascale, Nov.2000 Pendulation Damper (UCB)

31 E. Pascale, A. Boscaleri, Nov.2000 Connette la Gondola al Pallone Scansioni in azimut tramite la torsione Sulla catena di volo e la rotazione di una Ruota di inerzia Il Pivot Ava Hristov Movimento di elevazione: Inner frame ruotato Tramite un attuatore lineare

32 I sensori di posizione BOMERanG conta un volo di test, notturno, nel 1997 e quello ANTARTICO, diurno, del 98 Ci vogliono quindi due serie di sensori Tipo voloSensori GrossolaniSensori Fini NotturnoMagnetometro Flux Gate (1)(4) ( alta sensibilità, scarsa accuratezza ) Star Tracker (1)(3) ( determina completamente la soluzione attitudinale entro 2 arc-min rms ) DiurnoCoarse Sun Sensor (2)(4) ( Sei foto-resistenze, accuratezza ~ 1°) CCD bilineare solare (2)(4) (~ 1 arc-min rms ) EntrambeGPS Differenziale: assetto entro 10Giroscopio a tre assi (3) ( 10 arc-sec rms ) Puntamento in Elevazione: Encoder assoluto ottico a 16bit (20 Arc sec) Puntamento in Azimut (1) – IROE(2) – La Sapienza(3) – Caltech(4) - ING

33 Il Controllo Un sistema completamente digitale permette grande versatilità Raggi Cosmici possono indurre errori nellelettronica Due CPU 386 ridondanti: acquisiscono i sensori controllano i motori (controller PWM) Un Watch Dog in pochi ms commuta il controllo fra le due CPU nel caso una fosse ferma per un evento da CR Interfaccia comandi tdress – gondola Elettronica di potenza motori E. Pascale, A. Boscaleri Nov. 2000

34 BOOMERanG Scan Strategy Abbiamo una sovrapposi- zione ottimale sulla regione di cielo osservata P.de Bernardis Oct.2000 Esploriamo il cielo con scansioni lineari in azimut tutto lesperimento è ruotato d i +30°, 1 o 2°/s. Il centro della scansione traccia lazimuth a minore foreground

35 Performance Volo Anntartico: Il Sensore Solare provvede un misura precisa e ripetibile di azimut ed elevazione della navicella, tuttavia il segnale è difficile da calibrare essendo dipendente sia dallazimut che dallelevazione del Sole (accuratezza arc-min rms) Per questo si integrano i tre giroscopi sul SS. Il Giroscopio di roll fornisce il rollio ignoto al SS Attitude reconstruction: migliore di 3 arc-min rms Volo di test: La telecamera stellare fornisce la posizione della navicella negli angoli di azimut, elevazione e rollio entro 2 ar-min rms a 5 Hz Su questa vengono integrati i tre giroscopi per la rimozione degli offset Attitude reconstruction: migliore di 0.5 arc-min rms E. Pascale, Nov. 2000

36 Archeops Star Sensor A linear array of 46 photodiodes in the focus of a 40cm f/5 telescope. Heavily baffled. Red filter to maximize stars to atmosphere ratio. Attitude reconstruction: better than 1 arcmin. See Nati et al. RSI 74, 4169, 2003.

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39 The polar-night flight of Archeops

40 Stars Great night-time performance: 1300 stars/circle

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43 Poor day-time performance: payload reflections and large-scale atmospheric diffusion of sun light. (stars are around ten ADU !) During the Trapani flight we got also day-time data:

44 Poor day-time performance: payload reflections and large-scale atmospheric diffusion of sun light. (stars are around ten ADU !) Scattered sunlight one azimuth rotation