LiteBIRD, the next-generation cosmic microwave background (CMB) experiment, aims for a launch in Japan’s fiscal year 2032, marking a major advancement in the exploration of primordial cosmology and fundamental physics. Orbiting the Sun-Earth Lagrangian point L2, this JAXA-led strategic L-class mission will conduct a comprehensive mapping of the CMB polarization across the entire sky. During its 3-year mission, LiteBIRD will employ three telescopes within 15 unique frequency bands (ranging from 34 through 448 GHz), targeting a sensitivity of 2.2 μK-arcmin and a resolution of 0.5° at 100 GHz. Its primary goal is to measure the tensor-toscalar ratio r with an uncertainty δr = 0.001, including systematic errors and margin. If r ≥ 0.01, LiteBIRD expects to achieve a > 5σ detection in the ℓ = 2–10 and ℓ = 11–200 ranges separately, providing crucial insight into the early Universe. We describe LiteBIRD’s scientific objectives, the application of systems engineering to mission requirements, the anticipated scientific impact, and the operations and scanning strategies vital to minimizing systematic effects. We will also highlight LiteBIRD’s synergies with concurrent CMB projects.
The QUIJOTE (Q-U-I joint Tenerife) experiment combines the operation of two radio-telescopes and three instruments working in the microwave bands 10–20 GHz, 26–36 GHz and 35–47 GHz at the Teide Observatory, Tenerife, and has already been presented in previous SPIE meetings (Hoyland, R. J. et al, 2012; Rubi˜no-Mart´ın et al., 2012). The Cosmology group at the IAC have designed a new upgrade to the MFI instrument in the band 10–20 GHz. The aim of the QUIJOTE telescopes is to characterise the polarised emission of the cosmic microwave background (CMB), as well as galactic and extra-galactic sources, at medium and large angular scales. This MFI2 will continue the survey at even higher sensitivity levels. The MFI2 project led by the Instituto de Astrof´ısica de Canarias (IAC) consists of five polarimeters, three of them operating in the sub-band 10–15 GHz, and two in the sub-band 15–20 GHz. The MFI2 instrument is expected to be a full two–three times more sensitive than the former MFI. The microwave complex correlator design has been replaced by a simple correlator design with a digital back-end based on the latest Xilinx FPGAs (ZCU111). During the first half of 2019 the manufacture of the new cryostat was completed and since then the opto-mechanical components have been designed and manufactured. It is expected that the cryogenic front-end will be completed by the end of 2022 along with the FPGA acquisition and observing system. This digital system has been employed to be more robust against stray ground-based and satellite interference, having a frequency resolution of 1 MHz
LiteBIRD, the Lite (Light) satellite for the study of B-mode polarization and Inflation from cosmic background Radiation Detection, is a space mission for primordial cosmology and fundamental physics. JAXA selected LiteBIRD in May 2019 as a strategic large-class (L-class) mission, with its expected launch in the late 2020s using JAXA's H3 rocket. LiteBIRD plans to map the cosmic microwave background (CMB) polarization over the full sky with unprecedented precision. Its main scientific objective is to carry out a definitive search for the signal from cosmic inflation, either making a discovery or ruling out well-motivated inflationary models. The measurements of LiteBIRD will also provide us with an insight into the quantum nature of gravity and other new physics beyond the standard models of particle physics and cosmology. To this end, LiteBIRD will perform full-sky surveys for three years at the Sun-Earth Lagrangian point L2 for 15 frequency bands between 34 and 448 GHz with three telescopes, to achieve a total sensitivity of 2.16 μK-arcmin with a typical angular resolution of 0.5° at 100 GHz. We provide an overview of the LiteBIRD project, including scientific objectives, mission requirements, top-level system requirements, operation concept, and expected scientific outcomes.
LiteBIRD has been selected as JAXA’s strategic large mission in the 2020s, to observe the cosmic microwave background (CMB) B-mode polarization over the full sky at large angular scales. The challenges of LiteBIRD are the wide field-of-view (FoV) and broadband capabilities of millimeter-wave polarization measurements, which are derived from the system requirements. The possible paths of stray light increase with a wider FoV and the far sidelobe knowledge of -56 dB is a challenging optical requirement. A crossed-Dragone configuration was chosen for the low frequency telescope (LFT : 34–161 GHz), one of LiteBIRD’s onboard telescopes. It has a wide field-of-view (18° x 9°) with an aperture of 400 mm in diameter, corresponding to an angular resolution of about 30 arcminutes around 100 GHz. The focal ratio f/3.0 and the crossing angle of the optical axes of 90◦ are chosen after an extensive study of the stray light. The primary and secondary reflectors have rectangular shapes with serrations to reduce the diffraction pattern from the edges of the mirrors. The reflectors and structure are made of aluminum to proportionally contract from warm down to the operating temperature at 5 K. A 1/4 scaled model of the LFT has been developed to validate the wide field-of-view design and to demonstrate the reduced far sidelobes. A polarization modulation unit (PMU), realized with a half-wave plate (HWP) is placed in front of the aperture stop, the entrance pupil of this system. A large focal plane with approximately 1000 AlMn TES detectors and frequency multiplexing SQUID amplifiers is cooled to 100 mK. The lens and sinuous antennas have broadband capability. Performance specifications of the LFT and an outline of the proposed verification plan are presented.
LiteBIRD is a JAXA-led Strategic Large-Class mission designed to search for the existence of the primordial gravitational waves produced during the inflationary phase of the Universe, through the measurements of their imprint onto the polarization of the cosmic microwave background (CMB). These measurements, requiring unprecedented sensitivity, will be performed over the full sky, at large angular scales, and over 15 frequency bands from 34 GHz to 448 GHz. The LiteBIRD instruments consist of three telescopes, namely the Low-, Medium-and High-Frequency Telescope (respectively LFT, MFT and HFT). We present in this paper an overview of the design of the Medium-Frequency Telescope (89{224 GHz) and the High-Frequency Telescope (166{448 GHz), the so-called MHFT, under European responsibility, which are two cryogenic refractive telescopes cooled down to 5 K. They include a continuous rotating half-wave plate as the first optical element, two high-density polyethylene (HDPE) lenses and more than three thousand transition-edge sensor (TES) detectors cooled to 100 mK. We provide an overview of the concept design and the remaining specific challenges that we have to face in order to achieve the scientific goals of LiteBIRD.
Y. Inome, G. Ambrosi, Y. Awane, H. Baba, A. Bamba, M. Barceló, U. Barres de Almeida, J. Barrio, O. Blanch Bigas, J. Boix, L. Brunetti, E. Carmona, E. Chabanne, M. Chikawa, N. Cho, P. Colin, J. Contreras, J. Cortina, F. Dazzi, A. Deangelis, G. Deleglise, C. Delgado, C. Díaz, F. Dubois, A. Fiasson, D. Fink, N. Fouque, L. Freixas, C. Fruck, A. Gadola, R. García, D. Gascón, N. Geffroy, N. Giglietto, F. Giordano, F. Grañena, S. Gunji, R. Hagiwara, N. Hamer, Y. Hanabata, T. Hassan, K. Hatanaka, T. Haubold, M. Hayashida, R. Hermel, D. Herranz, K. Hirotani, J. Hose, D. Hugh, S. Inoue, Y. Inoue, K. Ioka, C. Jablonski, M. Kagaya, H. Katagiri, J. Kataoka, H. Kellermann, T. Kishimoto, M. Knoetig, K. Kodani, K. Kohri, T. Kojima, Y. Konno, S. Koyama, H. Kubo, J. Kushida, G. Lamanna, T. Le Flour, M. López-Moya, R. López, E. Lorenz, P. Majumdar, A. Manalaysay, M. Mariotti, G. Martínez, M. Martinez, S. Masuda, S. Matsuoka, D. Mazin, U. Menzel, J. Miranda , R. Mirzoyan, I. Monteiro, A. Moralejo, K. Murase, S. Nagataki, T. Nagayoshi, D. Nakajima, T. Nakamori, K. Nishijima, K. Noda, A. Nozato, M. Ogino, Y. Ohira, M. Ohishi, H. Ohoka, A. Okumura, S. Ono, R. Orito, J. Panazol, D. Paneque, R. Paoletti, J. Paredes, G. Pauletta, S. Podkladkin, J. Prast, R. Rando, O. Reimann, M. Ribó, S. Rosier-Lees, K. Saito, T. Saito, Y. Saito, N. Sakaki, R. Sakonaka, A. Sanuy, M. Sawada, V. Scalzotto, S. Schultz, T. Schweizer, T. Shibata, S. Shu, J. Sieiro, V. Stamatescu, S. Steiner, U. Straumann, R. Sugawara, H. Tajima, H. Takami, M. Takahashi, S. Tanaka, M. Tanaka, L. Tejedor, Y. Terada, M. Teshima, Y. Tomono, T. Totani, T. Toyama, Y. Tsubone, Y. Tsuchiya, S. Tsujimoto, H. Ueno, K. Umehara, Y. Umetsu, A. Vollhardt, R. Wagner, H. Wetteskind, T. Yamamoto, R. Yamazaki, A. Yoshida, T. Yoshida, T. Yoshikoshi
The Large Size Telescopes, LSTs, located at the center of the Cherenkov Telescope Array, CTA, will be sensitive
for low energy gamma-rays. The camera on the LST focal plane is optimized to detect low energy events based
on a high photon detection efficiency and high speed electronics. Also the trigger system is designed to detect
low energy showers as much as possible. In addition, the camera is required to work stably without maintenance
in a few tens of years. In this contribution we present the design of the camera for the first LST and the status
of its development and production.
J.-F. Glicenstein, M. Barcelo, J.-A. Barrio, O. Blanch, J. Boix, J. Bolmont, C. Boutonnet, P. Brun, E. Chabanne, C. Champion, S. Colonges, P. Corona, B. Courty, E. Delagnes, C. Delgado, C. Diaz, J.-P. Ernenwein, S. Fegan, O. Ferreira, M. Fesquet, G. Fontaine, N. Fouque, F. Henault, D. Gascón, B. Giebels, D. Herranz, R. Hermel, D. Hoffmann, D. Horan, J. Houles, P. Jean, S. Karkar, J. Knödlseder, G. Martinez, G. Lamanna, T. LeFlour, A. Lévêque, R. Lopez-Coto, F. Louis, Y. Moudden, E. Moulin, P. Nayman, F. Nunio, J.-F. Olive, J.-L. Panazol, S. Pavy, P.-O. Petrucci, M. Punch, Julie Prast, P. Ramon, S. Rateau, M. Ribó, S. Rosier-Lees, A. Sanuy, P. Sizun, J. Sieiro, K.-H. Sulanke, J.-P. Tavernet, L. A. Tejedor, F. Toussenel, G. Vasileiadis, V. Voisin, V. Waegebert, C. Zurbach
NectarCAM is a camera designed for the medium-sized telescopes of the Cherenkov Telescope Array (CTA) covering the central energy range 100 GeV to 30 TeV. It has a modular design based on the NECTAr chip, at the heart of which is a GHz sampling Switched Capacitor Array and 12-bit Analog to Digital converter. The camera will be equipped with 265 7-photomultiplier modules, covering a field of view of 7 to 8 degrees. Each module includes the photomultiplier bases, High Voltage supply, pre-amplifier, trigger, readout and Thernet transceiver. Events recorded last between a few nanoseconds and tens of nanoseconds. A flexible trigger scheme allows to read out very long events. NectarCAM can sustain a data rate of 10 kHz. The camera concept, the design and tests of the various subcomponents and results of thermal and electrical prototypes are presented. The design includes the mechanical structure, the cooling of electronics, read-out, clock distribution, slow control, data-acquisition, trigger, monitoring and services. A 133-pixel prototype with full scale mechanics, cooling, data acquisition and slow control will be built at the end of 2014.
The QUIJOTE-CMB project has been described in previous publications. Here we present the current status of the
QUIJOTE multi-frequency instrument (MFI) with five separate polarimeters (providing 5 independent sky pixels): two
which operate at 10-14 GHz, two which operate at 16-20 GHz, and a central polarimeter at 30 GHz. The optical
arrangement includes 5 conical corrugated feedhorns staring into a dual reflector crossed-draconian system, which
provides optimal cross-polarization properties (designed to be < −35 dB) and symmetric beams. Each horn feeds a novel
cryogenic on-axis rotating polar modulator which can rotate at a speed of up to 1 Hz. The science driver for this first
instrument is the characterization of the galactic emission. The polarimeters use the polar modulator to derive linear
polar parameters Q, U and I and switch out various systematics. The detection system provides optimum sensitivity
through 2 correlated and 2 total power channels. The system is calibrated using bright polarized celestial sources and
through a secondary calibration source and antenna. The acquisition system, telescope control and housekeeping are all
linked through a real-time gigabit Ethernet network. All communication, power and helium gas are passed through a
central rotary joint. The time stamp is synchronized to a GPS time signal. The acquisition software is based on PLCs
written in Beckhoffs TwinCat and ethercat. The user interface is written in LABVIEW. The status of the QUIJOTE MFI
will be presented including pre-commissioning results and laboratory testing.
The QUIJOTE (Q-U-I JOint Tenerife) CMB Experiment will operate at the Teide Observatory with the aim
of characterizing the polarisation of the CMB and other processes of Galactic and extragalactic emission in the
frequency range of 10-40GHz and at large and medium angular scales. The first of the two QUIJOTE telescopes
and the first multi-frequency (10-30GHz) instrument are already built and have been tested in the laboratory.
QUIJOTE-CMB will be a valuable complement at low frequencies for the Planck mission, and will have the
required sensitivity to detect a primordial gravitational-wave component if the tensor-to-scalar ratio is larger
than r = 0.05.
KEYWORDS: Sensors, Optical filters, Modulation transfer functions, Linear filtering, Image filtering, Signal detection, Optimal filtering, Numerical simulations, Digital filtering, Astronomy
We consider filters for the detection and extraction of compact
sources on a background. We make a one-dimensional treatment (though a
generalization to two or more dimensions is possible) assuming that
the sources have a Gaussian profile whereas the background is modeled by an homogeneous and isotropic Gaussian random field, characterized by a scale-free power spectrum. Local peak detection is used after
filtering. Then, a Bayesian Generalized Neyman-Pearson test is
used to define the region of acceptance that includes not only the
amplification but also the curvature of the sources and the a priori
probability distribution function of the sources. We search for an
optimal filter between a family of Matched-type filters (MTF) modifying the filtering scale such that it gives the maximum number of real detections once fixed the number density of spurious sources. We have performed numerical simulations to test theoretical ideas.
We present scale-adaptive filters that optimize the detection/separation of compact sources on a background. We assume that the sources have a multiquadric profile and a background modeled by an homogeneous and isotropic random field characterized by a power spectrum. We make an n-dimensional treatment but consider two interesting physical applications related to clusters of galaxies (Sunyaev-Zel'dovich effect and X-ray emission). We extend this methodology to multifrequency maps, introducing multifilters that optimize the detection on clusters on microwave maps. We apply these multifilters to small patches (corresponding to 10 frequency channels) of the sky such as the ones that will produce the future ESA Planck mission. Our method predicts a number of ≈10000 clusters in 2/3 of the sky, being the catalog complete over fluxes S > 170mJy at 300GHz.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.