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1.
  • Battersby, C., et al. (author)
  • The Origins Space Telescope
  • 2018
  • In: Nature Astronomy. - : Springer Science and Business Media LLC. - 2397-3366. ; 2:8, s. 596-599
  • Journal article (other academic/artistic)abstract
    • The Origins Space Telescope, one of four large Mission Concept Studies sponsored by NASA for review in the 2020 US Astrophysics Decadal Survey, will open unprecedented discovery space in the infrared, unveiling our cosmic origins.
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2.
  • Hirschauer, Alec S., et al. (author)
  • Imaging of I Zw 18 by JWST. I. Detecting Dusty Stellar Populations
  • 2024
  • In: Astronomical Journal. - 1538-3881 .- 0004-6256. ; 168:1
  • Journal article (peer-reviewed)abstract
    • We present a JWST imaging survey of I Zw 18, the archetypal extremely metal-poor, star-forming (SF), blue compact dwarf galaxy. With an oxygen abundance of only similar to 3% Z circle dot, it is among the lowest-metallicity systems known in the local Universe, and is, therefore, an excellent accessible analog for the galactic building blocks which existed at early epochs of ionization and star formation. These JWST data provide a comprehensive infrared (IR) view of I Zw 18 with eight filters utilizing both Near Infrared Camera (F115W, F200W, F356W, and F444W) and Mid-Infrared Instrument (F770W, F1000W, F1500W, and F1800W) photometry, which we have used to identify key stellar populations that are bright in the near- and mid-IR. These data allow for a better understanding of the origins of dust and dust-production mechanisms in metal-poor environments by characterizing the population of massive, evolved stars in the red supergiant (RSG) and asymptotic giant branch (AGB) phases. In addition, it enables the identification of the brightest dust-enshrouded young stellar objects (YSOs), which provide insight into the formation of massive stars at extremely low metallicities typical of the very early Universe. This paper provides an overview of the observational strategy and data processing, and presents first science results, including identifications of dusty AGB, RSG, and bright YSO candidates. These first results assess the scientific quality of JWST data and provide a guide for obtaining and interpreting future observations of the dusty and evolved stars inhabiting compact dwarf SF galaxies in the local Universe.
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3.
  • Leisawitz, David, et al. (author)
  • Origins Space Telescope: Baseline mission concept
  • 2021
  • In: Journal of Astronomical Telescopes, Instruments, and Systems. - 2329-4221 .- 2329-4124. ; 7:1
  • Journal article (peer-reviewed)abstract
    • The Origins Space Telescope will trace the history of our origins from the time dust and heavy elements permanently altered the cosmic landscape to present-day life. How did galaxies evolve from the earliest galactic systems to those found in the Universe today? How do habitable planets form? How common are life-bearing worlds? To answer these alluring questions, Origins will operate at mid-and far-infrared (IR) wavelengths and offer powerful spectroscopic instruments and sensitivity three orders of magnitude better than that of the Herschel Space Observatory, the largest telescope flown in space to date. We describe the baseline concept for Origins recommended to the 2020 US Decadal Survey in Astronomy and Astrophysics. The baseline design includes a 5.9-m diameter telescope cryocooled to 4.5 K and equipped with three scientific instruments. A mid-infrared instrument (Mid-Infrared Spectrometer and Camera Transit spectrometer) will measure the spectra of transiting exoplanets in the 2.8 to 20 μm wavelength range and offer unprecedented spectrophotometric precision, enabling definitive exoplanet biosignature detections. The far-IR imager polarimeter will be able to survey thousands of square degrees with broadband imaging at 50 and 250 μm. The Origins Survey Spectrometer will cover wavelengths from 25 to 588 μm, making wide-area and deep spectroscopic surveys with spectral resolving power R ∼ 300, and pointed observations at R ∼ 40,000 and 300,000 with selectable instrument modes. Origins was designed to minimize complexity. The architecture is similar to that of the Spitzer Space Telescope and requires very few deployments after launch, while the cryothermal system design leverages James Webb Space Telescope technology and experience. A combination of current-state-of-the-art cryocoolers and next-generation detector technology will enable Origins' natural background-limited sensitivity.
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4.
  • Leisawitz, David, et al. (author)
  • The origins space telescope
  • 2019
  • In: Proceedings of SPIE - The International Society for Optical Engineering. - : SPIE. - 0277-786X .- 1996-756X. ; 11115
  • Conference paper (peer-reviewed)abstract
    • The Origins Space Telescope will trace the history of our origins from the time dust and heavy elements permanently altered the cosmic landscape to present-day life. How did galaxies evolve from the earliest galactic systems to those found in the universe today? How do habitable planets form? How common are life-bearing worlds? To answer these alluring questions, Origins will operate at mid-and far-infrared wavelengths and offer powerful spectroscopic instruments and sensitivity three orders of magnitude better than that of Herschel, the largest telescope flown in space to date. After a 3 1/2 year study, the Origins Science and Technology Definition Team will recommend to the Decadal Survey a concept for Origins with a 5.9-m diameter telescope cryocooled to 4.5 K and equipped with three scientific instruments. A mid-infrared instrument (MISC-T) will measure the spectra of transiting exoplanets in the 2.8-20 μm wavelength range and offer unprecedented sensitivity, enabling definitive biosignature detections. The Far-IR Imager Polarimeter (FIP) will be able to survey thousands of square degrees with broadband imaging at 50 and 250 μm. The Origins Survey Spectrometer (OSS) will cover wavelengths from 25-588 μm, make wide-area and deep spectroscopic surveys with spectral resolving power R ∼ 300, and pointed observations at R ∼ 40,000 and 300,000 with selectable instrument modes. Origins was designed to minimize complexity. The telescope has a Spitzer-like architecture and requires very few deployments after launch. The cryo-thermal system design leverages JWST technology and experience. A combination of current-state-of-the-art cryocoolers and next-generation detector technology will enable Origins' natural backgroundlimited sensitivity.
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5.
  • Leisawitz, David, et al. (author)
  • The Origins Space Telescope: Mission concept overview
  • 2018
  • In: Proceedings of SPIE - The International Society for Optical Engineering. - : SPIE. - 0277-786X .- 1996-756X. ; 10698
  • Conference paper (peer-reviewed)abstract
    • Downloading of the abstract is permitted for personal use only. The Origins Space Telescope (OST) will trace the history of our origins from the time dust and heavy elements permanently altered the cosmic landscape to present-day life. How did the universe evolve in response to its changing ingredients? How common are life-bearing planets? To accomplish its scientific objectives, OST will operate at mid- and far-infrared wavelengths and offer superlative sensitivity and new spectroscopic capabilities. The OST study team will present a scientifically compelling, executable mission concept to the 2020 Decadal Survey in Astrophysics. To understand the concept solution space, our team studied two alternative mission concepts. We report on the study approach and describe both of these concepts, give the rationale for major design decisions, and briefly describe the mission-enabling technology.
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6.
  • Meixner, Margaret, et al. (author)
  • Herschel and ALMA measurements of dust and molecules in supernova 1987A
  • 2013
  • In: Proceedings of Science. - 1824-8039. ; Part F113823
  • Conference paper (peer-reviewed)abstract
    • Dust production by supernovae is important in the dust life cycle of a galaxy. The explosion of SN 1987A was the nearest SN detected in the last 400 years, allowing us detailed studies of contemporary evolution of a supernova for the first time. In 2011, Matsuura et al. reported 0.4-0.7 M of dust in SN 1987A based on Herschel HERITAGE survey data, which is surprisingly large compared to prior measurements of supernovae. In this paper, we present our follow-up studies of this important discovery about SN 1987A using the Herschel Space Observatory and the Atacama Large Millimeter Array (ALMA). We highlight two important results, the detection of cold molecular gas and dust in the ejected material of SN 1987A. Our results suggest that SNe are significant producers of dust and molecules, as well as heavy elements, driving chemical evolution of galaxies.
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7.
  • Meixner, Margaret, et al. (author)
  • Origins Space Telescope science drivers to design traceability
  • 2021
  • In: Journal of Astronomical Telescopes, Instruments, and Systems. - 2329-4221 .- 2329-4124. ; 7:1
  • Journal article (peer-reviewed)abstract
    • The Origins Space Telescope (Origins) concept is designed to investigate the creation and dispersal of elements essential to life, the formation of planetary systems, and the transport of water to habitable worlds and the atmospheres of exoplanets around nearby K-and M-dwarfs to identify potentially habitable-and even inhabited-worlds. These science priorities are aligned with NASA's three major astrophysics science goals: How does the Universe work? How did we get here? and Are we alone? We briefly describe the science case that arose from the astronomical community and the science traceability matrix for Origins. The science traceability matrix prescribes the design of Origins and demonstrates that it will address the key science questions motivated by the science case.
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8.
  • Meixner, Margaret, et al. (author)
  • Overview of the Origins Space telescope: Science drivers to observatory requirements
  • 2018
  • In: Proceedings of SPIE - The International Society for Optical Engineering. - : SPIE. - 0277-786X .- 1996-756X. ; 10698
  • Conference paper (peer-reviewed)abstract
    • The Origins Space Telescope (OST) mission concept study is the subject of one of the four science and technology definition studies supported by NASA Headquarters to prepare for the 2020 Astronomy and Astrophysics Decadal Survey. OST will survey the most distant galaxies to discern the rise of metals and dust and to unveil the co-evolution of galaxy and blackhole formation, study the Milky Way to follow the path of water from the interstellar medium to habitable worlds in planetary systems, and measure biosignatures from exoplanets. This paper describes the science drivers and how they drove key requirements for OST Mission Concept 2, which will operate between ∼5 and ∼600 microns with a JWST sized telescope. Mission Concept 2 for the OST study optimizes the engineering for the key science cases into a powerful and more economical observatory compared to Mission Concept 1.
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9.
  • Wiedner, M.C., et al. (author)
  • A Proposed Heterodyne Receiver for the Origins Space Telescope
  • 2018
  • In: IEEE Transactions on Terahertz Science and Technology. - 2156-342X .- 2156-3446. ; 8:6, s. 558-571
  • Journal article (peer-reviewed)abstract
    • The HEterodyne Receiver for the Origins Space Telescope (HERO) is a proposed design for a heterodyne focal plane array for a large space mission. The Origins Space Telescope (OST) is one of the four missions selected to be studied by NASA for the 2020 Astronomy and Astrophysics Decadal survey. HERO is designed to observe the trail of water from the interstellar medium (ISM) to disks around protostars. In Concept 1, HERO provides continuous frequency coverage from 468 to 2700 GHz in five bands and a sixth band to cover 4700 GHz. Most bands include 2 × 64 pixels providing at least an order of magnitude higher mapping speeds than available with today's instruments. Receiver sensitivities are expected to be close to the quantum limit. HERO Concept 2, highly constrained by cost and denoted Little-HERO, includes four bands with continuous coverage from 486 to 2700 GHz and with focal plane arrays having only 2 × 9 pixels per band. Both of these THz receiver concepts will be described and the designs will be motivated by the science drivers, the space craft constraints and the latest technological developments. The HERO design builds on the highly successful Herschel/Heterodyne Instrument for the Far-Infrared, on Stratospheric Observatory for Far-Infrared Astronomy/upGREAT and many other heterodyne receivers, but surpasses these in terms of frequency coverage, array size and sensitivity, thanks to the latest technical advances. HERO can be considered an example of a new generation of heterodyne focal plane arrays for future space missions.
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10.
  • Wiedner, M.C., et al. (author)
  • Heterodyn receiver for the Origins Space Telescope concept 2
  • 2018
  • In: Proceedings of SPIE - The International Society for Optical Engineering. - : SPIE. - 0277-786X .- 1996-756X. ; 10698
  • Conference paper (peer-reviewed)abstract
    • The Origins Space Telescope (OST) is a NASA study for a large satellite mission to be submitted to the 2020 Decadal Review. The proposed satellite has a fleet of instruments including the HEterodyne Receivers for OST (HERO). HERO is designed around the quest to follow the trail of water from the ISM to disks around protostars and planets. HERO will perform high-spectral resolution measurements with 2x9 pixel focal plane arrays at any frequency between 468GHz to 2,700GHz (617 to 111 μm). HERO builds on the successful Herschel/HIFI heritage, as well as recent technological innovations, allowing it to surpass any prior heterodyne instrument in terms of sensitivity and spectral coverage.
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11.
  • Wiedner, M.C., et al. (author)
  • Heterodyne Receiver for Origins
  • 2021
  • In: Journal of Astronomical Telescopes, Instruments, and Systems. - 2329-4221 .- 2329-4124. ; 7:1
  • Journal article (peer-reviewed)abstract
    • The Heterodyne Receiver for Origins (HERO) is the first detailed study of a heterodyne focal plane array receiver for space applications. HERO gives the Origins Space Telescope the capability to observe at very high spectral resolution (R = 107) over an unprecedentedly large far-infrared (FIR) wavelengths range (111 to 617 μm) with high sensitivity, with simultaneous dual polarization and dual-frequency band operation. The design is based on prior successful heterodyne receivers, such as Heterodyne Instrument for the Far-Infrared/Herschel, but surpasses it by one to two orders of magnitude by exploiting the latest technological developments. Innovative components are used to keep the required satellite resources low and thus allowing for the first time a convincing design of a large format heterodyne array receiver for space. HERO on Origins is a unique tool to explore the FIR universe and extends the enormous potential of submillimeter astronomical spectroscopy into new areas of astronomical research.
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12.
  • Wiedner, M.C., et al. (author)
  • Origins space telescope: from first light to life
  • 2021
  • In: Experimental Astronomy. - : Springer Science and Business Media LLC. - 0922-6435 .- 1572-9508. ; 51:3, s. 595-624
  • Journal article (peer-reviewed)abstract
    • The Origins Space Telescope (Origins) is one of four science and technology definition studies selected by the National Aeronautics and Space Administration (NASA) in preparation of the 2020 Astronomy and Astrophysics Decadal survey in the US. Origins will trace the history of our origins from the time dust and heavy elements permanently altered the cosmic landscape to present-day life. It is designed to answer three major science questions: How do galaxies form stars, make metals, and grow their central supermassive black holes from reionization? How do the conditions for habitability develop during the process of planet formation? Do planets orbiting M-dwarf stars support life? Origins operates at mid- to far-infrared wavelengths from ~ 2.8 μm to 588 μm, and is more than 1000 times more sensitive than prior far-IR missions due to its cold (~ 4.5 K) aperture and state-of-the-art instruments.
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13.
  • Wiedner, M.C., et al. (author)
  • The origins space telescope and the heterodyne receiver for origins (HERO)
  • 2019
  • In: ISSTT 2019 - 30th International Symposium on Space Terahertz Technology, Proceedings Book. ; , s. 204-207
  • Conference paper (peer-reviewed)abstract
    • The Origins Space Telescope is one of four large mission concept studies carried out by NASA for the 2020 Decadal survey. Origins is a far-infrared telescope designed to understand the evolution of galaxies and black holes, to follow the trail of water from protostars to habitable planets and to search for biosignatures in the atmospheres of exoplanets. The Heterodyne Receiver for Origins (HERO) is the high spectral resolution receiver. It is the first heterodyne array receiver designed to fly on a satellite and an example for possible future focal plane arrays for space. HERO has focal plane arrays with nine pixels in two polarization. HERO covers a large frequency range between 486 and 2700 GHz in only 4 frequency bands, requiring local oscillators with fractional bandwidth of 45%. HERO uses the best superconducting mixers with noise temperatures between 1 and 3 hf/k and an intermediate bandwidth of 6 to 8 GHz. HERO can carry out dual polarization and dual-frequency observations. The major challenges for the HERO design are the low cooling power and the low electrical power available on a spacecraft, which impact the choice of the cryogenic amplifiers and backends. SiGe cryogenic amplifiers with a consumption of less than 0.5 mW, as well as CMOS spectrometers with a power consumption below 2W are the baseline for HERO. The development plan includes broadband (45%) multiplier-amplifier chains, low noise mixers (1-3 hf/k), low-power consuming (< 05.mW) cryogenic amplifiers and low-power consuming spectrometer backends (< 2W).
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14.
  • Wright, Gillian, et al. (author)
  • The Mid-infrared Instrument for JWST and Its In-flight Performance
  • 2023
  • In: Publications of the Astronomical Society of the Pacific. - 0004-6280 .- 1538-3873. ; 135:1046
  • Journal article (peer-reviewed)abstract
    • The Mid-Infrared Instrument (MIRI) extends the reach of the James Webb Space Telescope (JWST) to 28.5 μm. It provides subarcsecond-resolution imaging, high sensitivity coronagraphy, and spectroscopy at resolutions of λ/Δλ ∼ 100-3500, with the high-resolution mode employing an integral field unit to provide spatial data cubes. The resulting broad suite of capabilities will enable huge advances in studies over this wavelength range. This overview describes the history of acquiring this capability for JWST. It discusses the basic attributes of the instrument optics, the detector arrays, and the cryocooler that keeps everything at approximately 7 K. It gives a short description of the data pipeline and of the instrument performance demonstrated during JWST commissioning. The bottom line is that the telescope and MIRI are both operating to the standards set by pre-launch predictions, and all of the MIRI capabilities are operating at, or even a bit better than, the level that had been expected. The paper is also designed to act as a roadmap to more detailed papers on different aspects of MIRI.
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15.
  • Zanardo, Giovanna, et al. (author)
  • SPECTRAL AND MORPHOLOGICAL ANALYSIS OF THE REMNANT OF SUPERNOVA 1987A WITH ALMA AND ATCA
  • 2014
  • In: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 796:2
  • Journal article (peer-reviewed)abstract
    • We present a comprehensive spectral and morphological analysis of the remnant of supernova (SN) 1987A with the Australia Telescope Compact Array (ATCA) and the Atacama Large Millimeter/submillimeter Array (ALMA). The non-thermal and thermal components of the radio emission are investigated in images from 94 to 672 GHz (lambda 3.2 mm to 450 mu m), with the assistance of a high-resolution 44 GHz synchrotron template from the ATCA, and a dust template from ALMA observations at 672 GHz. An analysis of the emission distribution over the equatorial ring in images from 44 to 345 GHz highlights a gradual decrease of the east-to-west asymmetry ratio with frequency. We attribute this to the shorter synchrotron lifetime at high frequencies. Across the transition from radio to far infrared, both the synchrotron/dust-subtracted images and the spectral energy distribution (SED) suggest additional emission beside the main synchrotron component (S-nu proportional to nu(-0.73)) and the thermal component originating from dust grains at T similar to 22 K. This excess could be due to free-free flux or emission from grains of colder dust. However, a second flat-spectrum synchrotron component appears to better fit the SED, implying that the emission could be attributed to a pulsar wind nebula (PWN). The residual emission is mainly localized west of the SN site, as the spectral analysis yields -0.4 less than or similar to alpha less than or similar to -0.1 across the western regions, with alpha similar to 0 around the central region. If there is a PWN in the remnant interior, these data suggest that the pulsar may be offset westward from the SN position.
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