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The Italian View of B-Pol P. de Bernardis and the Italian team. The Italian HW groups :. Milano (Bersanelli, Mennella et al.) Milano Bicocca (Gervasi, Sironi, et al.) Torino (Tascone et al.) Bologna (Carretti, Cortiglioni, Mandolesi, Valenziano, Villa, et al.) Firenze (Natale et al.)
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The Italian View of B-PolP. de Bernardisand the Italian team
The Italian HW groups : • Milano (Bersanelli, Mennella et al.) • Milano Bicocca (Gervasi, Sironi, et al.) • Torino (Tascone et al.) • Bologna (Carretti, Cortiglioni, Mandolesi, Valenziano, Villa, et al.) • Firenze (Natale et al.) • Roma La Sapienza (de Bernardis, De Petris, Masi et al.) Heritage: BOOMERanG, Planck-HFI, Planck-LFI, SPORT, Bar-SPORT, OLIMPO All started in the COFIS study of “Themes and Models in Cosmology and Fundamental Physics” funded in 2004 by the Italian Space Agency
ASI studies • The Italian Space Agency has supported in 2004 a study on “Themes and Models in Cosmology and Fundamental Physics from Space”. • All the members of the Italian cosmology community have contributed to this study, which was delivered on Oct. 20, 2004.
Piano Aerospaziale Nazionale 2006-2008 Agenzia Spaziale Italiana http://www.asi.it/html/ita/news/20060124_Executive_Summary.pdf
EXAMPLE Tab. 2‑1: Overview of the driving mission requirements for the B-POL satellite.
No real instrument study, yet • Many issues require further experimentation - thinking. • The most important ones are: • Mass production of detectors (sensitivity) • Knowledge of polarized foregrounds and optimization of sky coverage / sky scan • Instrumental Systematics • Polarization modulation • For these reasons we do not have a full proposal • Here we want to give contributions for discussion
Sensitivity • At variance with interferometers, Bolometer technology is easily scalable, and the throughput can be larger than l2. • Focal planes hosting thousands of bolometers are being developed already. • Intense activity in this field is ongoing in Berkeley, JPL-Caltech, Cardiff, SRON … • How many detectors do we really need for a B-modes survey ? A. Lee, Berkeley
FWHM = 0.5°, T=1 year NET = 150 mK/sqrt(Hz) r = 0.03
FWHM = 0.5° T=1 year NET = 150 mK/sqrt(Hz) 500 detectors Cfr. Challinor & Chon Astro-ph/0410097 10000 detectors 50% Analysis by G. Polenta
Italian TESs : • GASTALDO L., GALLINARO G., GATTI F., PERGOLESI D., RIBEIRO GOMES M., REPETTO P., DUSSONI S., VALLE R., MANFRINETTI P., CHINCARINI A. (2006). Study of the δ-Al/Ag superconducting alloy for TES applications. NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH. SECTION A, ACCELERATORS, SPECTROMETERS, DETECTORS AND ASSOCIATED EQUIPMENT. vol. 559 pp. 465-467 ISSN: 0168-9002 2. • GATTI F., PIRO L., PERGOLESI D., COLASANTI L., GASTALDO L., RIBEIRO GOMES M., REPETTO P. (2006). TES microcalorimeter development for future Italian X-ray astronomy missions. NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH. SECTION A, ACCELERATORS, SPECTROMETERS, DETECTORS AND ASSOCIATED EQUIPMENT. vol. 559 pp. 605-607 ISSN: 0168-9002
PRIN 2006 • We have setup a national collaboration to develop a large-format, polarization-sensitive bolometer array camera at 90 GHz. • This is a collaboration of the following groups • Roma (de Bernardis, Masi, Vittorio, Dall’ Oglio) • Milano (Bersanelli, Gervasi) • Genova (Gatti) • Bologna (Mandolesi) • Padova/Trieste (De Zotti – Pasian) • The camera, based on Horn-coupled TES bolometers, will fill with 300 detectors the corrected focal plane of a 2.6m telescope (we have one in the Alps (MITO), one in Antarctica (COCHISE) and a balloon-borne one (OLIMPO). Det. architecture, Cryogenics, Readout Passive Frontend TES, wafer processing Passive frontend Analysis, science
R C RIC Rivelatori a Induttanza Cinetica La Sapienza - Roma IRST-ITC – Trento INFN funds + Cardiff (Mauskopf)
R C KID Kinetic Inductance Detectors La Sapienza - Roma IRST-ITC – Trento INFN funds + Cardiff (Mauskopf)
R C Mazin (Caltech)
R C 0.3K - 0.1K GHz RF (…+fN-1+fN+fN+1+…) CMB CMB CMB Pixel N fN Pixel N+1 fN+1 Pixel N-1 fN-1
R C RF mux • A KID has high transmission at f away from resonance. This fact can naturally be used for multiplexing many detectors, tuned at different resonances f, all loading the same transmission line. • Using excitation in the GHz range: • high quality wireless components are available • thousands of detectors can be multiplexed, with a single coax and a single HEMT
Detector Krytar 201 La Sapienza: Measurement Testbed5-10 GHz Pulse Tube Refrigerator and 3He/4He fridge 0.3K Directional Detector Krytar 1820
Corrugated feed horn at 44 GHz • Designed, made (by electro-erosion on aluminum) and tested in Italy • Milano Group (Bersanelli, Mennella et al.)
Corrugated feed horn at 44 GHz • Designed, made (by electro-erosion on aluminum) and tested in Italy • Milano Group (Bersanelli, Mennella et al.)
Riccardo Tascone et al.:Five-Level Waveguide Correlation Unit (European Patent, 05019553.6)Ka band Impressive Performance:
Figure 3. Spectral distribution of the elements of . . Figure 4. Spectral distribution of the elements of
Return Loss at each of the four ports > 30 dB; • Isolation of 70 dB; • Cross-couplings of -65 dB; • Group Delay equalization within ± 5 ps; • Insertion Loss < 0.1÷0.2 dB. R. Tascone et al. OMT for Ka band
Can all this be extended to higher frequencies, keeping the same performance ? • Under study.
FETBOX CQM on Planck
FETBOX Flight Model The JFET BOX: 72 diff. Channels, < 200mW @ 50K, 5 nV/sqrt(Hz)
130K 50K 50K
130K 50K 50K D. Brienza et al., “Cryogenic Preamplifiers for high resistance bolometers”, WOLTE-7 - ESA-WPP-264, pg. 283-288, (2006).
the BOOMERanG balloon-borne telescope Sun Shield Solar Array Differential GPS Array Star Camera Cryostat and detectors Ground Shield Primary Mirror (1.3m) B03 Sensitive at 145, 245, 345 GHz
The Fridge S. Masi et al. Cryogenics, 38, 319-324, 1998 Cryopump It works with charcoal carbon grains It adsorbs when T < 12 K (mechanical thermal switch) It desorbs when T > 20 K (heater) Condensation point Thermally connected to the 4He bath with 2 gold plated high purity copper rods Pumping tubes Thin wall stainless steel tubes Liquid 3He evaporator T = 0.280 K Volume = 130 cm3 34 STP liters of 3He gas Holding time: 14 days
ASI-OLIMPO Cryostat for 130 bolometric detectors (both TESs and Semiconductors)
PILOT - CNES • Cryostat for large bolometer arrays (1024@240mm + 1024@550mm) • Main challanges: • Radiation shields • Thermalization of bolo cables • Weight & Size
Industrial support for Cryogenics • In Italy: • Alenia • CECOM • Galileo Avionica • LMP • RIAL • ….
The “Paolorizer” for BOOMERanG-B03 XPol<1x10-3 S. Masi et al. 2006, A&A, 458, 687-716 , astro-ph/0507509
We also had a calibration lamp in the Lyot stop of BOOMERanG and.. • … surprise surprise, it is polarized ! Cal Lamp
The LFI calibration BB calibrator
RCA AIV (2/2) LFI cold loads
Scientific Objectives: • E–modes free from systematic effects • B– modes at the best we can do • lmax = ~ 500 for distinguish primordial B mode from lensing B mode • Precise polarized foreground maps (~ 0.1 uK) for systematics and astrophysics • 1st Level Requirements: • L2 orbit (for systematic effects) • Frequency Coverage: 20 GHz to 500 GHz would be ideal for accurate cleaning of the various classes of foregrounds and astrophysical studies. Low end difficult due to telescope size.Feasibility of a strictly linked ground based program ? • Sky coverage: Full sky • Detector Technology: different technologies exist. It would be good to crosscheck systematics with at least one frequency band with different technology • Polarimetry needed
2nd Level Requirements • Sensitivity: < 0.1 mK * sec^(-1/2). See note (*) • FWHM: depends on science. See note (**) • Lifetime: 4 full sky surveys 2 years • Number of detectors: few 103 / frequency. See note (***) • Technology: HEMT from 20 to 100; Bolometers from 70 to 500 GHz. • Cryogenics: Depending on the detectors used (type, number, dissipation) and mission requirements (lifetime, spacecraft size etc.), the mission cryo chain could be a combination of the following possible systems: • From 300K to ~50K, ~3 passive radiators (V-Grooves?) in L2; or their combination with active coolers, mechanical (low vibration) or sorption, to reduce number/dimensions of passive stages • Below ~50K • sorption/JT cooler with H2 or Ne + sorption/JT He • mechanical cooler (pulse tube, vibration level?) • Liquid/solid cryogens • From ~5K to 0.1K, • dilution cooler • ADR • OMT based architecture for high purity polarization measurements.
Separate telescopes for different bands ? • Appealing option because • It allows to mazimize the size of polarization-pure focal planes • It reduces integration complexity • If on two separate satellites: easier optimization of scan strategy (4 Planck satellites can be fitted inside the ARIANE V) . • Moving bands to GND and Balloons will help with budget !