65 results on '"John C. Mather"'
Search Results
2. Astrostationary orbits for hybrid space and ground-based observatories
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Eliad Peretz, Christine Hamilton, John C. Mather, Simone D’Amico, Adam Michaels, Robert Pritchett, Wayne Yu, and Peter Wizinowich
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Space and Planetary Science ,Control and Systems Engineering ,Mechanical Engineering ,Astronomy and Astrophysics ,Instrumentation ,Electronic, Optical and Magnetic Materials - Published
- 2022
3. Exoplanet imaging performance envelopes for starshade-based missions
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Kevin Hall, Eliad Peretz, Stuart B. Shaklan, John C. Mather, and Sergi Hildebrandt
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Solar System ,Computer science ,Mechanical Engineering ,Astronomy and Astrophysics ,Stellar classification ,01 natural sciences ,Exoplanet ,Electronic, Optical and Magnetic Materials ,010309 optics ,Background noise ,Stars ,Signal-to-noise ratio (imaging) ,Space and Planetary Science ,Control and Systems Engineering ,Planet ,0103 physical sciences ,Range (statistics) ,Astrophysics::Earth and Planetary Astrophysics ,010303 astronomy & astrophysics ,Instrumentation ,Remote sensing - Abstract
We lay out the capabilities and limitations of starshade-based missions aiming to measure the reflected light spectra of temperate planets from an imaging perspective. We use the Starshade Imaging Simulation Toolkit for Exoplanet Reconnaissance to conduct high fidelity end-to-end optical simulations, taking a step forward from simplified analytical equations, exploring and quantifying the impact of an array of observational conditions, including natural parameters such as target star types, planet types, distances, planet phases, and exo-zodiacal dust, and starshade perturbations such as tilt, shift off line of sight, edge errors, and glint. We find that signal-to-noise ratio (SNR) requirements used for establishing detection and spectral characterization, is not suitable under realistic observation conditions for a wide range of targets. We show that even if we assume that the spatially distributed, time-varying background noise could be known and calibrated to a level of 1%, each target star will need its own SNR requirement based on its unique observation conditions, nearly always resulting in a higher threshold SNR, with values as high as X5 from currently established requirement, and in some cases impossible to detect. We conduct statistical analysis using end-to-end optical simulations, taking into account observationally based priors and update previously established completeness values for an array of target stars and mission configurations, accounting for starshade perturbations, and background knowledge at a level of one percent and find that completeness values are negatively impacted and reduced by up to 50% across targets even at ranges shorter than 10 pc. Finally, we utilize information from over hundreds of thousands of detailed imaging simulations to map accessible target stars for both optimistic and pessimistic scenarios, reassessing the expected capabilities of starshade-based high contrast direct imaging missions.
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- 2021
4. Mapping the observable sky for a Remote Occulter working with ground-based telescopes
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Eliad Peretz, Sara Seager, Sergi Hildebrandt, Lucas Pabarcius, Stuart B. Shaklan, John C. Mather, Phil Willems, and Kevin Hall
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Computer science ,Mechanical Engineering ,media_common.quotation_subject ,Astrophysics::Instrumentation and Methods for Astrophysics ,Astronomy and Astrophysics ,Observable ,Exoplanet ,Electronic, Optical and Magnetic Materials ,Stars ,Space and Planetary Science ,Control and Systems Engineering ,Sky ,Planet ,Astrophysics::Earth and Planetary Astrophysics ,Device simulation ,Instrumentation ,Exposure duration ,Remote sensing ,media_common - Abstract
We present the optical requirement-driven observational constraints of the Remote Occulter, an orbiting starshade designed to work with ground-based telescopes to produce visible-band images and spectra of temperate planets around Sun-like stars. We then utilize these constraints to develop and present numerical simulations of time-dependent observable sky regions along with each region’s nightly available exposure duration and show that nearly the entire sky could be observed for up to 8 h a night. We further examine how changes introduced to our established constraints will impact such observational windows and discuss their implications, setting the ground for upcoming studies aiming to further investigate the Remote Occulter mission capabilities and architecture.
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- 2021
5. Origins Space Telescope
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Asantha Cooray, J. Scott Knight, Daniel Ramspacker, Chi K. Wu, Gary J. Melnick, Kartik Sheth, Jonathan J. Fortney, Perry Knollenberg, Edward Bergin, Matthew East, Tiffany Kataria, Porfirio Beltran, Gregory E. Martins, Karin Sandstrom, John Steeves, Cara Battersby, Itsuki Sakon, John Pohner, Johannes G. Staguhn, Thomas P. Greene, Michael J. DiPirro, Samuel H. Moseley, Lenward T. Seals, Charles M. Bradford, Michael Petach, S. Tompkins, Joseph M. Howard, Benjamin J. Gavares, Edward L. Wright, Michael Jacoby, Joaquin Vieira, Jonathan W. Arenberg, David Leisawitz, Kiarash Tajdaran, Elvire De Beck, Thanh Nguyen, J. Bolognese, Kate Y. L. Su, Douglas Scott, Alexandra Pope, Eric Stoneking, Christopher Derkacz, Cassandra Webster, Thomas L. Roellig, Kevin L. Denis, Tracee L. Jamison, David Folta, Zachary A. Granger, Ruth Carter, Lisa Kaltenegger, Desika Narayanan, Danny Chi, Alex Griffiths, Sarah Lipscy, Martina C. Wiedner, Charles R. Lawrence, Frank Helmich, Kimberly Ennico, Jeffrey R. Olson, Lynn N. Allen, James Bauer, John C. Mather, Susan G. Neff, L. Hilliard, Keith Harvey, George Harpole, Kevin B. Stevenson, Paul A. Lightsey, Edward Amatucci, James A. Corsetti, Eric E. Mamajek, Larry Sokolsky, Denis Burgarella, Louis G. Fantano, Joseph A. Generie, C. Sandin, Ted Mooney, Bob G. Beaman, D. Padgett, Anisa Jamil, Damon Bradley, Tom D'Asto, Stefanie N. Milam, Gregory Feller, Jonas Zmuidzinas, Raymond M. Bell, Margaret Meixner, Klaus M. Pontoppidan, Dominic Benford, Alison Nordt, Larry Dewell, Maryvonne Gerin, Lee Armus, Susanna Petro, Samantha Edgington, C. Paul Earle, Sean Carey, Alison Rao, and Astronomy
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spectroscopy ,Computer science ,space telescope ,galaxy evolution ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,law.invention ,010309 optics ,Telescope ,Spitzer Space Telescope ,law ,0103 physical sciences ,Transit (astronomy) ,cryogenic ,planet formation ,010303 astronomy & astrophysics ,Instrumentation ,Astrophysics::Galaxy Astrophysics ,Scientific instrument ,Spectrometer ,Planetary habitability ,Mechanical Engineering ,James Webb Space Telescope ,Astrophysics::Instrumentation and Methods for Astrophysics ,Astronomy ,Astronomy and Astrophysics ,Exoplanet ,Electronic, Optical and Magnetic Materials ,Space and Planetary Science ,Control and Systems Engineering ,infrared ,biosignatures ,Astrophysics::Earth and Planetary Astrophysics - 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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- 2021
6. Origins Space Telescope: trades and decisions leading to the baseline mission concept
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David Leisawitz, David C. Redding, John Steeves, Greg Feller, Martina C. Wiedner, Charles R. Lawrence, Jonathan W. Arenberg, James Bauer, Deborah Padgett, Johannes Staguhn, Jonathan J. Fortney, Thomas P. Greene, Alison Nordt, Gerard L. Rafanelli, Paul A. Lightsey, Matthew East, Edward Amatucci, Asantha Cooray, Bret G. Drake, Damon Bradley, Ray Bell, Klaus M. Pontoppidan, Jonas Zmuidzinas, Kate Y. L. Su, J. Booth, Kevin B. Stevenson, Edwin A. Bergin, Cara Battersby, Dominic Benford, John C. Mather, Larry Dewell, Samuel H. Moseley, Lee Armus, Zachary A. Granger, Angel Flores, C. Sandin, Edward L. Wright, Joaquin Vieira, George H. Rieke, Gary J. Melnick, Kartik Sheth, Tiffany Kataria, Charles M. Bradford, John S. Knight, James A. Corsetti, Ruth Carter, Desika Narayanan, Michael J. DiPirro, Karin Sandstrom, Lynn N. Allen, Sean Carey, Lawrence M. Sokolsky, David Yanatsis, Joseph M. Howard, Alexandra Pope, Kimberly Ennico, Stefanie N. Milam, Cassandra Webster, Craig W. McMurtry, Anita Sengupta, Margaret Meixner, Thomas L. Roellig, Itsuki Sakon, C. Wu, Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA (UMR_8112)), Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-CY Cergy Paris Université (CY)
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Computer science ,Space (commercial competition) ,01 natural sciences ,7. Clean energy ,law.invention ,010309 optics ,Telescope ,Spitzer Space Telescope ,law ,0103 physical sciences ,Architecture ,Baseline (configuration management) ,010303 astronomy & astrophysics ,Instrumentation ,Scientific instrument ,[PHYS]Physics [physics] ,Planetary habitability ,Mechanical Engineering ,James Webb Space Telescope ,Astronomy and Astrophysics ,Electronic, Optical and Magnetic Materials ,13. Climate action ,Space and Planetary Science ,Control and Systems Engineering ,Systems engineering ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] - Abstract
International audience; 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? We describe how Origins was designed to answer these alluring questions. We discuss the key decisions taken by the Origins mission concept study team, the rationale for those choices, and how they led through an exploratory design process to the Origins baseline mission concept. To understand the concept solution space, we studied two distinct mission concepts and descoped the second concept, aiming to maximize science per dollar and hit a self-imposed cost target. We report on the study approach and describe the concept evolution. The resulting baseline design includes a 5.9-m diameter telescope cryocooled to 4.5 K and equipped with three scientific instruments. The chosen architecture is similar to that of the Spitzer Space Telescope and requires very few deployments after launch. The cryo-thermal system design leverages James Webb Space Telescope technology and experience.
- Published
- 2021
7. Microwave spectro-polarimetry of matter and radiation across space and time
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Mattia Negrello, Guilaine Lagache, Selim C. Hotinli, F. Piacentini, Marta B. Silva, Dale J. Fixsen, Helmut Dannerbauer, Íñigo Zubeldia, J. Colin Hill, Jose Alberto Rubino Martin, Naonori Sugiyama, Kazunori Kohri, Simone Ferraro, Tarun Souradeep, Kirit Karkare, Maximilian H. Abitbol, N. Mandolesi, Andrea Tartari, L. Rodriguez, Alan J. Kogut, K. Karatsu, José Luis Bernal, Suvodip Mukherjee, Nabila Aghanim, I. Khabibullin, Zhen-Yi Cai, Subodh P. Patil, Matteo Bonato, Carlo Burigana, Tiziana Trombetti, Jean-Baptiste Melin, Marcelo A. Alvarez, David Alonso, Emanuela Dimastrogiovanni, François R. Bouchet, John C. Mather, Daniela Paoletti, R. A. Sunyaev, Gianfranco De Zotti, Luke Hart, Boris Bolliet, Patrick C. Breysse, Eugene Churazov, Ely D. Kovetz, Paolo de Bernardis, Silvia Masi, Eric R. Switzer, Matthieu Béthermin, Aditya Rotti, Douglas Scott, Jochem J. A. Baselmans, Julien Lesgourgues, V. Reveret, Jose Ramon Bermejo Climent, Carlos Martins, Jens Chluba, Garrett K. Keating, Nathalie Palanque-Delabrouille, Bruno Maffei, Yacine Ali-Haïmoud, Jens Erler, Eleonora Di Valentino, Srinivasan Raghunathan, Nicholas Battaglia, Azadeh Moradinezhad Dizgah, Jack Sayers, Mathew S. Madhavacheril, A. J. Banday, Shaul Hanany, Joseph Silk, Tony Mroczkowski, Daisuke Nagai, Akira Endo, Mathieu Remazeilles, Jacques Delabrouille, Fabio Finelli, James G. Bartlett, Kaustuv Basu, Andrea Ravenni, Carlos Hernández-Monteagudo, AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), European Commission, Ministerio de Ciencia, Innovación y Universidades (España), Ministerio de Economía y Competitividad (España), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), and Physics of Nanodevices
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cosmological model ,dimension: 3 ,Cosmic microwave background ,Galaxy clusters ,cosmic background radiation ,CMB ,7. Clean energy ,01 natural sciences ,Early Universe ,General Relativity and Quantum Cosmology ,flow: velocity ,law.invention ,mass spectrum ,neutrino ,law ,Observatory ,DISTORTIONS ,ENERGY-RELEASE ,010303 astronomy & astrophysics ,Physics ,COSMIC BACKGROUND-RADIATION ,formation ,Astrophysics::Instrumentation and Methods for Astrophysics ,imaging ,HYDROGEN ,Cosmology ,observatory ,black body ,Sunyaev-Zel'dovich effect ,[PHYS.GRQC]Physics [physics]/General Relativity and Quantum Cosmology [gr-qc] ,Astrophysics - Instrumentation and Methods for Astrophysics ,Astronomical and Space Sciences ,radiation: background ,Astrophysics - Cosmology and Nongalactic Astrophysics ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,polarization: anisotropy ,lens ,Cosmic background radiation ,Polarimetry ,FOS: Physical sciences ,General Relativity and Quantum Cosmology (gr-qc) ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astronomy & Astrophysics ,Sunyaev–Zel'dovich effect ,energy: injection ,MAGNETIC-FIELDS ,Telescope ,0103 physical sciences ,Angular resolution ,structure ,[PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det] ,inflation ,010306 general physics ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,Astrophysics::Galaxy Astrophysics ,Spectrometer ,beam: width ,HOT-MODEL ,deformation ,gravitational radiation ,Astronomy ,Astronomy and Astrophysics ,CLUSTER ,Galaxies ,Astrophysics - Astrophysics of Galaxies ,THERMALIZATION ,cosmic background radiation: temperature ,angular resolution ,13. Climate action ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,microwaves: emission ,ddc:520 ,spectral ,spectrometer ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] - Abstract
Delabrouille, J., et al., This paper discusses the science case for a sensitive spectro-polarimetric survey of the microwave sky. Such a survey would provide a tomographic and dynamic census of the three-dimensional distribution of hot gas, velocity flows, early metals, dust, and mass distribution in the entire Hubble volume, exploit CMB temperature and polarisation anisotropies down to fundamental limits, and track energy injection and absorption into the radiation background across cosmic times by measuring spectral distortions of the CMB blackbody emission. In addition to its exceptional capability for cosmology and fundamental physics, such a survey would provide an unprecedented view of microwave emissions at sub-arcminute to few-arcminute angular resolution in hundreds of frequency channels, a data set that would be of immense legacy value for many branches of astrophysics. We propose that this survey be carried out with a large space mission featuring a broad-band polarised imager and a moderate resolution spectro-imager at the focus of a 3.5 m aperture telescope actively cooled to about 8K, complemented with absolutely-calibrated Fourier Transform Spectrometer modules observing at degree-scale angular resolution in the 10–2000 GHz frequency range. We propose two observing modes: a survey mode to map the entire sky as well as a few selected wide fields, and an observatory mode for deeper observations of regions of specific interest., This work has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant agreement No 725456, CMBSPEC) as well as the Royal Society (grants UF130435 and RG140523). JARM acknowledges financial support from the Spanish Ministry of Science and Innovation (MICINN) under the project AYA2017-84185-P, and from the European Union’s Horizon 2020 research and innovation programme under Grant Agreement 687312 (RADIOFOREGROUNDS). C.H.-M. acknowledges the support of the Spanish Ministry of Science through project PGC2018-097585-B-C21. Financial support from the ASI/Physics Department of the University of Roma–Tor Vergata agreement n. 2016-24-H.0 for study activities of the Italian cosmology community is acknowledged. JLB is supported by the Allan C. and Dorothy H. Davis Fellowship, and has been supported by the Spanish MINECO under grant BES-2015-071307, co-funded by the ESF during part of the development of this work.
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- 2021
8. COSMIC INFRARED BACKGROUND FLUCTUATIONS IN DEEP SPITZER INFRARED ARRAY CAMERA IMAGES: DATA PROCESSING AND ANALYSIS
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John C. Mather, S. H. Moseley, A. Kashlinsky, and R. G. Arendt
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Physics ,education.field_of_study ,Population ,Shot noise ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Galaxy ,Spectral line ,Luminosity ,Space and Planetary Science ,Cosmic infrared background ,education ,Astrophysics::Galaxy Astrophysics ,Noise (radio) ,Data reduction - Abstract
This paper provides a detailed description of the data reduction and analysis procedures that have been employed in our previous studies of spatial fluctuation of the cosmic infrared background (CIB) using deep Spitzer IRAC observations. The self-calibration we apply removes a strong instrumental signal from the fluctuations which would otherwise corrupt our results. The procedures and results for masking bright sources, and modeling faint sources down to levels set by the instrumental noise are presented. Various tests are performed to demonstrate that the resulting power spectra of these fields are not dominated by instrumental or procedural effects. These tests indicate that the large scale (>~30') fluctuations that remain in the deepest fields are not directly related to the galaxies that are bright enough to be individually detected. We provide the parameterization of these power spectra in terms of separate instrument noise, shot noise, and power law components. Our measurements of spatial fluctuations of the CIB intensity indicate the mean emission from the objects producing the fluctuations is quite low (>~1 nW m-2 sr-1 at 3-5 micron), and thus consistent with current gamma-ray absorption constraints. The source of the fluctuations may be high-z Population III objects, or a more local component of very low luminosity objects with clustering properties that differ from the resolved galaxies. Finally, we discuss the prospects of the upcoming space-based surveys to directly measure the epochs inhabited by the populations producing these source-subtracted CIB fluctuations, and to isolate the individual fluxes of these populations.
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- 2009
9. Dynamical zodiacal cloud models constrained by high resolution spectroscopy of the zodiacal light
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S. Harvey Moseley, John C. Mather, Sergei I. Ipatov, Alexander Kutyrev, G. J. Madsen, and Ronald J. Reynolds
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Physics ,Zodiacal light ,010504 meteorology & atmospheric sciences ,Scattering ,Astronomy ,Astronomy and Astrophysics ,01 natural sciences ,Spectral line ,Jupiter ,Solar wind ,Radiation pressure ,13. Climate action ,Space and Planetary Science ,Planet ,Physics::Space Physics ,0103 physical sciences ,Astrophysics::Solar and Stellar Astrophysics ,Astrophysics::Earth and Planetary Astrophysics ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,0105 earth and related environmental sciences ,Line (formation) - Abstract
The simulated Doppler shifts of the solar Mg I Fraunhofer line produced by scattering on the solar light by asteroidal, cometary, and trans-neptunian dust particles are compared with the shifts obtained by Wisconsin H-Alpha Mapper (WHAM) spectrometer. The simulated spectra are based on the results of integrations of the orbital evolution of particles under the gravitational influence of planets, the Poynting–Robertson drag, radiation pressure, and solar wind drag. Our results demonstrate that the differences in the line centroid position in the solar elongation and in the line width averaged over the elongations for different sizes of particles are usually less than those for different sources of dust. The deviation of the derived spectral parameters for various sources of dust used in the model reached maximum at the elongation (measured eastward from the Sun) between 90° and 120°. For the future zodiacal light Doppler shifts measurements, it is important to pay a particular attention to observing at this elongation range. At the elongations of the fields observed by WHAM, the model-predicted Doppler shifts were close to each other for several scattering functions considered. Therefore the main conclusions of our paper do not depend on a scattering function and mass distribution of particles if they are reasonable. A comparison of the dependencies of the Doppler shifts on solar elongation and the mean width of the Mg I line modeled for different sources of dust with those obtained from the WHAM observations shows that the fraction of cometary particles in zodiacal dust is significant and can be dominant. Cometary particles originating inside Jupiter's orbit and particles originating beyond Jupiter's orbit (including trans-neptunian dust particles) can contribute to zodiacal dust about 1/3 each, with a possible deviation from 1/3 up to 0.1–0.2. The fraction of asteroidal dust is estimated to be ∼0.3–0.5. The mean eccentricities of zodiacal particles located at 1–2 AU from the Sun that better fit the WHAM observations are between 0.2 and 0.5, with a more probable value of about 0.3.
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- 2008
10. Demonstrating the Negligible Contribution of Optical HST ACS Galaxies to Source-subtracted Cosmic Infrared Background Fluctuations in Deep Spitzer IRAC Images
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John C. Mather, A. Kashlinsky, R. G. Arendt, and Samuel H. Moseley
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Physics ,COSMIC cancer database ,Infrared ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,01 natural sciences ,Galaxy ,Redshift ,Luminosity ,Space and Planetary Science ,Cosmic infrared background ,0103 physical sciences ,Astrophysics::Earth and Planetary Astrophysics ,010306 general physics ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics - Abstract
We study the possible contribution of optical galaxies detected with the Hubble ACS instrument to the near-IR cosmic infrared (CIB) fluctuations in deep Spitzer images. The Spitzer data used in this analysis are obtained in the course of the GOODS project, from which we select four independent 10' × 10' regions observed at both 3.6 and 4.5 μm. ACS source catalogs for all of these areas are used to construct maps containing only their emissions in the ACS B,V,i,z bands. We find that deep Spitzer data exhibit CIB fluctuations remaining after removal of foreground galaxies of a very different clustering pattern at both 3.6 and 4.5 μm than the ACS galaxies could contribute. We also find that there are very good correlations between the ACS galaxies and the removed galaxies in the Spitzer maps, but practically no correlations remain with the residual Spitzer maps used to identify the CIB fluctuations. These contributions become negligible on larger scales used to probe the CIB fluctuations arising from clustering. This means that the ACS galaxies cannot contribute to the large-scale CIB fluctuations found in the residual Spitzer data. The absence of their contributions also means that the CIB fluctuations arise at z 6.5 as the Lyman break of their sources must be redshifted past the longest ACS band, or the fluctuations have to originate in the more local but extremely low luminosity galaxies.
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- 2007
11. Memory‐Efficient Up‐the‐Ramp Processing with Cosmic‐Ray Rejection
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D. J. Fixsen, John C. Mather, and Joel D. Offenberg
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Data processing ,Computer science ,business.industry ,Noise (signal processing) ,Volume (computing) ,Astronomy and Astrophysics ,Avionics ,Space and Planetary Science ,Component (UML) ,Telecommunications link ,business ,Downstream (networking) ,Computer hardware ,Scope (computer science) - Abstract
We introduce a memory-efficient method for processing up-the-ramp sampled data to reduce noise and remove cosmic-ray events. The method we describe includes initial processing in the readout electronics (onboard, in the case of a space mission) plus postprocessing downstream. This data processing approach can be used to record or downlink high-quality science data using a small fraction of the bits required to transmit the full data, potentially reducing the volume to 0.01-0.001 of its original size. The onboard component has the advantage that it "processes as you go," reducing the online memory requirements. The processing and memory requirements are modest and are within the scope of current-generation avionics systems. We discuss the requirements and the performance of the algorithm. We also demonstrate the quality of the resulting data.
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- 2005
12. Migration of small bodies and dust to the terrestrial planets
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John C. Mather and Sergei I. Ipatov
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Physics ,Orbital elements ,Solar System ,Astrophysics (astro-ph) ,Dust particles ,FOS: Physical sciences ,Astronomy ,Astronomy and Astrophysics ,Astrophysics ,Space and Planetary Science ,Asteroid ,Physics::Space Physics ,Terrestrial planet ,Particle ,Astrophysics::Earth and Planetary Astrophysics ,Order of magnitude - Abstract
We integrated the orbital evolution of 30,000 Jupiter-family comets, 1300 resonant asteroids, and 7000 asteroidal, trans-Neptunian, and cometary dust particles. For initial orbital elements of bodies close to those of Comets 2P, 10P, 44P, and 113P, a few objects got Earth-crossing orbits with semi-major axes $a$$, Comment: Submitted to Proc. of the IAU Colloquium N 197 "Dynamics of populations of planetary systems" (Belgrade, Serbia and Montenegro, 31 August - 4 September, 2004)
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- 2004
13. Analysis of the Diffuse Near‐Infrared Emission from Two‐Micron All‐Sky Survey Deep Integration Data: Foregrounds versus the Cosmic Infrared Background
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John C. Mather, A. Kashlinsky, Roc M. Cutri, Mike Skrutskie, and S. Odenwald
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Physics ,Zodiacal light ,Point source ,media_common.quotation_subject ,Spectral density ,Astronomy and Astrophysics ,Astrophysics ,Galaxy ,Space and Planetary Science ,Sky ,Cosmic infrared background ,Surface brightness ,Noise (radio) ,media_common - Abstract
This is one of two papers in which we report the detection of structure in the cosmic infrared background (CIB) between 1.25 - 2.2 micron through the use of data from the Two Micron Sky Survey (2MASS). This paper concentrates on data assembly, analysis and the estimate of the various foreground contributions; the companion paper (Kashlinsky, Odenwald, Mather, Skrutskie, Cutri 2002, hereafter KOMSC) presents the cosmological results for the CIB fluctuations and their implications. By using repeated observations of a specific calibration star field, we were able to achieve integration times in excess of 3900 seconds compared to the 7.8 seconds in the standard 2MASS data product. This yielded a point source detection limit (3 \sigma) of +18.5^m in K_s band. The resulting co-added images were processed to remove point sources to a limiting surface brightness of +20^m/arcsec$^2 or 40 nW/m^2/sr. The remaining maps contained over 90% of the pixels and were Fourier transformed to study the spatial structure of the diffuse background light. After removing resolved sources and other artifacts, we find that the power spectrum of the final images has a power-law distribution consistent with clustering by distant galaxies. We estimate here the contributions to this signal from Galactic foregrounds, atmospheric OH-glow, zodiacal light and instrument noise, all of which are small and of different slopes. Hence, this supports the KOMSC identification of the signal as coming from the CIB fluctuations produced by distant clustered galaxies.
- Published
- 2003
14. The Spectral Results of the Far‐Infrared Absolute Spectrophotometer Instrument onCOBE
- Author
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John C. Mather and D. J. Fixsen
- Subjects
Physics ,Far infrared ,Space and Planetary Science ,Orders of magnitude (temperature) ,Cosmic infrared background ,Cosmic microwave background ,Astrophysics::Instrumentation and Methods for Astrophysics ,Calibration ,Astronomy and Astrophysics ,Black-body radiation ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics - Abstract
The cosmic microwave background (CMB) spectral results of the Far-Infrared Absolute Spectrophotometer (FIRAS) instrument are summarized. Some questions that have been raised about the calibration accuracy are also addressed. Finally, we comment on the potential for major improvements with new measurement approaches. The measurement of the deviation of the CMB spectrum from a 2.725 ± 0.001 K blackbody form made by the COBE-FIRAS could be improved by nearly 2 orders of magnitude.
- Published
- 2002
15. Detection of Small-Scale Fluctuations in the Near-Infrared Cosmic Infrared Background from Long-Exposure 2MASS Fields
- Author
-
Mike Skrutskie, A. Kashlinsky, S. Odenwald, Roc M. Cutri, and John C. Mather
- Subjects
Physics ,Star formation ,media_common.quotation_subject ,Astrophysics (astro-ph) ,Astrophysics::Instrumentation and Methods for Astrophysics ,Airglow ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Galaxy ,Stars ,Space and Planetary Science ,Sky ,Cosmic infrared background ,Surface brightness ,Astrophysics::Galaxy Astrophysics ,Noise (radio) ,media_common - Abstract
We report first results for the cosmic infrared background (CIB) fluctuations at 1.25, 1.65 and 2.17 micron obtained from long exposures constructed from 2MASS standard star fields. We have co-added and analyzed scans from one such field with a total exposure time > 1 hour, and removed sources and other artifacts. The stars and galaxies were clipped out to K_s~19^m leaving only high-z galaxies (or possibly local low-surface-brightness systems). The residual component of the diffuse emission on scales from a few arc-sec to a few arc-min has a power-law slope consistent with emission produced by clustered galaxies. The noise (and residual artifacts) contribution to the signal is small and the colors of the signal are very different from Galactic stars or air-glow. We therefore identify the signal as CIB fluctuations from the faint unresolved galaxies. We show that the present-day galaxies with no evolution would produce a significant deficit in the observed CIB fluctuations. Thus the dominant contribution to the observed signal must come from high z and may indicate high rates of star formation at those epochs., Ap. J. Letters, in press
- Published
- 2002
16. Reconstructing emission from pre-reionization sources with cosmic infrared background fluctuation measurements by the JWST
- Author
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Kari Helgason, A. Kashlinsky, Richard G. Arendt, Samuel H. Moseley, John C. Mather, and Volker Bromm
- Subjects
Physics ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,Space and Planetary Science ,Cosmic infrared background ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Reionization ,Astrophysics::Galaxy Astrophysics ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We present new methodology to use cosmic infrared background (CIB) fluctuations to probe sources at 1030., Comment: ApJ, in press. Minor revisions/additions to match the version in proofs
- Published
- 2014
- Full Text
- View/download PDF
17. Validation of Up‐the‐Ramp Sampling with Cosmic‐Ray Rejection on Infrared Detectors
- Author
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D. J. Fixsen, R. Sengupta, Judy Pipher, William J. Forrest, M. A. Nieto-Santisteban, Robert E. McMurray, Robert J. Hanisch, H. S. Stockman, Joel D. Offenberg, M. E. McKelvey, Bernard J. Rauscher, and John C. Mather
- Subjects
Physics ,Observational error ,business.industry ,Astrophysics::High Energy Astrophysical Phenomena ,Detector ,Astrophysics::Instrumentation and Methods for Astrophysics ,Sampling (statistics) ,Astronomy and Astrophysics ,Cosmic ray ,Astrophysics ,Optics ,Space and Planetary Science ,Ir detector ,Focus (optics) ,business - Abstract
We examine cosmic ray rejection methodology on data collected from InSb and Si:As detectors. The application of an Up-the-Ramp sampling technique with cosmic ray identification and mitigation is the focus of this study. This technique is valuable for space-based observatories which are exposed to high-radiation environments. We validate the Up-the-Ramp approach on radiation-test data sets with InSb and Si:As detectors which were generated for SIRTF. The Up-the-Ramp sampling method studied in this paper is over 99.9% effective at removing cosmic rays and preserves the structure and photometric quality of the image to well within the measurement error.
- Published
- 2001
18. Cosmic‐Ray Rejection and Readout Efficiency for Large‐Area Arrays
- Author
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M. A. Nieto-Santisteban, John C. Mather, D. J. Fixsen, H. S. Stockman, Robert J. Hanisch, R. Sengupta, and J. D. Offenberg
- Subjects
Physics ,Pixel ,Astrophysics (astro-ph) ,Detector ,Process (computing) ,FOS: Physical sciences ,Astronomy and Astrophysics ,Cosmic ray ,Astrophysics ,Signal on ,Image (mathematics) ,Space and Planetary Science ,Code (cryptography) ,Algorithm - Abstract
We present an algorithm to optimally process uniformly sampled array image data obtained with a nondestructive readout. The algorithm discards full wells, removes cosmic ray (particle) hits and other glitches, and makes a nearly optimum estimate of the signal on each pixel. The algorithm also compresses the data. The computer requirements are modest, and the results are robust. The results are shown and compared to results of Fowler sampled and processed data. Non-ideal detector performance may require some additional code, but this is not expected to cost much processing time. Known types of detector faults are addressed., This paper has been accepted for publication in the PASP
- Published
- 2000
19. COBEFar Infrared Absolute Spectrophotometer Observations of Galactic Lines
- Author
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Charles L. Bennett, John C. Mather, and D. J. Fixsen
- Subjects
Physics ,media_common.quotation_subject ,Galactic Center ,Astronomy ,Flux ,Astronomy and Astrophysics ,Astrophysics ,Excitation temperature ,Galactic plane ,Spectral line ,Far infrared ,Space and Planetary Science ,Sky ,Line (formation) ,media_common - Abstract
The COBE Far Infrared Absolute Spectrophotometer (FIRAS) observations constitute an unbiased survey over the wavelength range from 100 μm to 1 cm over 99% of the sky. Improved calibration of the FIRAS instrument and the inclusion of all of the FIRAS data allow an improved signal-to-noise ratio determination of the spectral lines by a factor of ~2 over our previous results. The resolution is low (0.45 cm-1), so only the strongest lines are observable. The CO chain from J = 1-0 to J = 8-7 is observed toward the Galactic center. The line ratios are roughly consistent with a 40 K excitation temperature. The 157.7 μm C II and 205.3 μm N II lines are observable over most of the sky. The 370.4 and 609.1 μm lines of C I and the 121.9 μm line of N II are observed in the Galactic plane. The line ratios at the Galactic center are consistent with a density of n0 ~ 30 cm-3 and a UV flux of G0 ≈ 15 μW m-2 sr-1 (10 Habing units). The 269 μm H2O line is observed toward the Galactic center in absorption.
- Published
- 1999
20. TheCOBEDiffuse Infrared Background Experiment Search for the Cosmic Infrared Background. IV. Cosmological Implications
- Author
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Edward L. Wright, Samuel H. Moseley, Robert F. Silverberg, Y. C. Pei, D. J. Fixsen, Richard A. Shafer, T. Kelsall, N. Odegard, Michael G. Hauser, John C. Mather, R. G. Arendt, E. Dwek, David Leisawitz, and J. L. Weiland
- Subjects
Physics ,Diffuse Infrared Background Experiment ,Extragalactic background light ,Space and Planetary Science ,Star formation ,Cosmic infrared background ,Astrophysics (astro-ph) ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics - Abstract
In this paper we examine the cosmological constraints of the recent DIRBE and FIRAS detection of the extragalactic background light between 125-5000 microns on the metal and star formation histories of the universe., Comment: 38 pages and 9 figures. Accepted for publications in The Astrophysical Journal
- Published
- 1998
21. Quasi‐Stationary States of Dust Flows under Poynting‐Robertson Drag: New Analytical and Numerical Solutions
- Author
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Leonid M. Ozernoy, Nick Gorkavyi, Tanya Taidakova, and John C. Mather
- Subjects
Physics ,Orbital elements ,Solar System ,Zodiacal light ,Astrophysics (astro-ph) ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Planetary system ,Interplanetary dust cloud ,Continuity equation ,Space and Planetary Science ,Drag ,Physics::Space Physics ,Astrophysics::Solar and Stellar Astrophysics ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics::Galaxy Astrophysics ,Stationary state - Abstract
The effect of solar or stellar radiation on dust particles' trajectories (the Poynting-Robertson drag) has been studied by a number of authors and applied to interplanetary dust dynamics in numerical computations. Meanwhile some important features of dust flows can be studied analytically by implementing our novel hydrodynamical approach to use the continuity equation written in the particle's orbital elements as coordinates (Gor'kavyi, Ozernoy, & Mather 1997). By employing this approach and integrating the continuity equation, we are able to find two integrals of motion when the Poynting-Robertson drag dominates the dissipative forces in the dust flow. These integrals of motion enable us to explore basic characteristics of dust flows from any sources in the Solar system (such as asteroids, comets, Kuiper belt, etc.) or in another planetary system. In particular, we have reproduced the classical solution $n(r)\propto r^{-1}$ that approximately represents the overall distribution of dust in the Solar system. We have also investigated various factors that could be responsible for the deviations of the power law index in $n(r)\propto r^{\delta}$ from $\delta=-1$, including the influences of the orbital characteristics of dust sources, the evaporation of dust particles, as well as mixtures of dust particles of both asteroidal and cometary origin. We have calculated the masses and number densities of asteroidal and cometary components of the zodiacal cloud at different distances from the Sun., Comment: Accepted for publication in ApJ, v. 488, Oct. 10, 1997; 22 pages, Latex, 12 Postscript figures
- Published
- 1997
22. The Spectrum of the Cosmic Microwave Background Anisotropy from the CombinedCOBEFIRAS and DMR Observations
- Author
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John C. Mather, Gary Hinshaw, Charles L. Bennett, and D. J. Fixsen
- Subjects
Physics ,media_common.quotation_subject ,Spectrum (functional analysis) ,Cosmic microwave background ,Astrophysics::Instrumentation and Methods for Astrophysics ,Astronomy and Astrophysics ,Observable ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Radiation ,Frequency spectrum ,Space and Planetary Science ,Sky ,Anisotropy ,media_common - Abstract
We analyze the Cosmic Microwave Background (CMB) anisotropy data from the independent COBE FIRAS and DMR observations. We extract the frequency spectrum of the FIRAS signal that has the spatial distribution seen by DMR and show that it is consistent with CMB temperature fluctuations in the radiation well into the Wien region of the spectrum. Conversely, we form a map of the Planckian component of the sky temperature from FIRAS and show that it correlates with the DMR anisotropy map. The rms fluctuations at angular scales of 7 degrees are 48 \pm 14 uK for the FIRAS data compared with 35 \pm 2 uK for the DMR data and 31 \pm 6 uK for the correlated combination (1 sigma uncertainties). The consistency of these data, from very different instruments with very different observing strategies, provide compelling support for the interpretation that the signal seen by DMR is, in fact, temperature anisotropy of cosmological origin. The data also limit rms fluctuations in the Compton y parameter, observable via the Sunyaev- Zel'dovich effect, to Delta_y < 3 x 10^{-6} (95% CL) on 7 degree angular scales.
- Published
- 1997
23. A New Approach to Dynamical Evolution of Interplanetary Dust
- Author
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N. N. Gorkavyi, Leonid M. Ozernoy, and John C. Mather
- Subjects
Gravitation ,Orbital elements ,Physics ,Classical mechanics ,Continuity equation ,Space and Planetary Science ,Interplanetary medium ,Astronomy and Astrophysics ,Astrophysics::Earth and Planetary Astrophysics ,Circular orbit ,Coordinate space ,Resonance (particle physics) ,Numerical integration - Abstract
We introduce the continuity equation written in the coordinate space of the orbital elements (e.g., semimajor axis a versus eccentricity e, etc.). This equation can serve as an effective tool to analyze the transport of interplanetary dust particles as well as their dynamical evolution, and offers a very useful complement to the approach using purely numerical integration of orbits. Using the continuity equation and suitable analytical and numerical approximations, statistically useful results can be achieved very quickly, and new integrals of the motion can be sought to simplify the description of large-scale phenomena. This paper describes the method, illustrates it with a simple example of multiple gravitational scatterings of particles on planets in circular orbits in two dimensions, and outlines the program for further development with more accurate approximations. We describe the particle dynamical evolution due to gravitational scattering by means of the "scattering matrix" W(a, e, a', e') in the continuity equation. This matrix determines both the probability of transition and the value of the particle's shift from the point a, e to the point a', e'. For purposes of illustration, two cases of the zodiacal particle diffusion due to gravitational scattering are computed, which are characterized by the initial conditions (1) (asteroid case), a0 = 2.5 AU, e0 = 0.4 (resonance 1:3 with Jupiter), and (2) (comet case), a0 = 2.22 AU, e0 = 0.846 (comet Encke). We discuss the approximations of the example and how they might be improved in future work. These include treatments of the Poynting-Robertson drag, interparticle collisions, secular perturbations, three-dimensional orbits, and resonance capture by the planets. For instance, analytical expressions are available for the rates of gradual change of orbital elements due to the Poynting-Robertson and solar wind drags, which can be incorporated easily in the "div" terms of the continuity equation.
- Published
- 1997
24. Clustering of the Diffuse Infrared Light from the [ITAL]COBE[/ITAL] DIRBE Maps: An All-Sky Survey of [ITAL]C[/ITAL](0)
- Author
-
A. Kashlinsky, John C. Mather, and S. Odenwald
- Subjects
Physics ,Smoothness (probability theory) ,Infrared ,Wavelength range ,media_common.quotation_subject ,Astronomy and Astrophysics ,Astrophysics ,Galaxy ,Beam size ,Space and Planetary Science ,Sky ,Cosmic infrared background ,Cluster analysis ,media_common - Abstract
We measure the smoothness of the infrared sky using the COBE DIRBE maps, and obtain interesting limits on the production of the diffuse cosmic infrared background (CIB) light by matter clustered like galaxies. The predicted fluctuations of the CIB with the DIRBE beam size of 07 are of the order of 10%, and the maps are smooth at the level of δνIν ~ a few nW m-2 sr-1 rms from 2.2 to 100 μm. The lowest numbers are achieved at mid- to far-IR, where the foreground is bright but smooth; they are [C(0)]1/2 ≤ (1-1.5) nW m-2 sr-1 at λ = 10-100 μm. If the CIB comes from clustered matter evolving according to typical scenarios, then the smoothness of the maps implies CIB levels less than ~(10-15) nW m-2 sr-1 over this wavelength range.
- Published
- 1996
25. COSMIC INFRARED BACKGROUND FLUCTUATIONS AND ZODIACAL LIGHT
- Author
-
Samuel H. Moseley, A. Kashlinsky, Richard G. Arendt, and John C. Mather
- Subjects
Physics ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,Zodiacal light ,Infrared ,Astrophysics::Instrumentation and Methods for Astrophysics ,Ecliptic ,FOS: Physical sciences ,Spectral density ,Astronomy and Astrophysics ,White noise ,Astrophysics ,01 natural sciences ,Physics::Popular Physics ,Wavelength ,Space and Planetary Science ,Cosmic infrared background ,0103 physical sciences ,Angular resolution ,Astrophysics::Earth and Planetary Astrophysics ,010306 general physics ,010303 astronomy & astrophysics ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We have performed a specific observational test to measure the effect that the zodiacal light can have on measurements of the spatial fluctuations of the near-IR background. Previous estimates of possible fluctuations caused by zodiacal light have often been extrapolated from observations of the thermal emission at longer wavelengths and low angular resolution, or from IRAC observations of high latitude fields where zodiacal light is faint and not strongly varying with time. The new observations analyzed here target the COSMOS field, at low ecliptic latitude where the zodiacal light intensity varies by factors of $\sim2$ over the range of solar elongations at which the field can be observed. We find that the white noise component of the spatial power spectrum of the background is correlated with the modeled zodiacal light intensity. Roughly half of the measured white noise is correlated with the zodiacal light, but a more detailed interpretation of the white noise is hampered by systematic uncertainties that are evident in the zodiacal light model. At large angular scales ($\gtrsim100"$) where excess power above the white noise is observed, we find no correlation of the power with the modeled intensity of the zodiacal light. This test clearly indicates that the large scale power in the infrared background is not being caused by the zodiacal light., Comment: 17 pp. Accepted for publication in the ApJ
- Published
- 2016
26. Scientific results from COBE
- Author
-
Charles L. Bennett, G.F. Smooth, Rainer Weiss, Robert F. Silverberg, Samuel H. Moseley, Edward L. Wright, John C. Mather, T. Kelsall, T. L. Murdock, E. S. Cheng, N. W. Boggess, Richard A. Shafer, and Michael G. Hauser
- Subjects
Physics ,Atmospheric Science ,Infrared astronomy ,COSMIC cancer database ,Diffuse Infrared Background Experiment ,Cosmic microwave background ,Astrophysics::Instrumentation and Methods for Astrophysics ,Aerospace Engineering ,Astronomy ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Geophysics ,Space and Planetary Science ,Sky brightness ,Cosmic infrared background ,General Earth and Planetary Sciences ,Black-body radiation ,Astrophysics::Galaxy Astrophysics ,Background radiation - Abstract
NASA's Cosmic Background Explorer ( COBE 1 ) carries three scientific instruments to make precise measurements of the spectrum and anisotropy of the cosmic microwave background (CMB) radiation on angular scales greater than 7° and to conduct a search for a diffuse cosmic infrared background (CIB) radiation with 0.7° angular resolution. Data from the Far-InfraRed Absolute Spectrophotometer (FIRAS) show that the spectrum of the CMB is that of a blackbody of temperature T=2.73±0.06 K, with no deviation from a blackbody spectrum greater than 0.25% of the peak brightness. The first year of data from the Differential Microwave Radiometers (DMR) show statistically significant CMB anisotropy. The anisotropy is consistent with a scale invariant primordial density fluctuation spectrum. Infrared sky brightness measurements from the Diffuse InfraRed Background Experiment (DIRBE) provide new conservative upper limits to the CIB. Extensive modeling of solar system and galactic infrared foregrounds is required for further improvement in the CIB limits.
- Published
- 1993
27. The Wide-field Infrared Survey Explorer (WISE): Mission Description and Initial On-orbit Performance
- Author
-
Robert S. McMillan, Scott Schick, Mohamed Abid, Chao-Wei Tsai, Larry Naes, I. Heinrichsen, John C. Mather, Deborah L. Padgett, Ian S. McLean, Mark A. Shannon, Joel Cardon, Edward L. Wright, Mark Schwalm, Dominic J. Benford, J. Davy Kirkpatrick, Andrew Blain, Martha Kendall, Spencer A. Stanford, Mark F. Larsen, William R. Irace, B. Mendez, Beth Fabinsky, Roc M. Cutri, Valerie G. Duval, Peter Eisenhardt, David Leisawitz, Martin Cohen, Michael F. Skrutskie, Fengchuan Liu, Amy L. Walsh, Don Royer, Russell G. Walker, Michael E. Ressler, Thomas H. Jarrett, Carol J. Lonsdale, Amy Mainzer, Joan Howard, and Thomas N. Gautier
- Subjects
Zodiacal light ,Infrared ,media_common.quotation_subject ,Ecliptic ,Astronomy ,FOS: Physical sciences ,Astronomy and Astrophysics ,Space and Planetary Science ,Observatory ,Sky ,Orbit (dynamics) ,Satellite ,Angular resolution ,Astrophysics - Instrumentation and Methods for Astrophysics ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,Geology ,media_common - Abstract
The all sky surveys done by the Palomar Observatory Schmidt, the European Southern Observatory Schmidt, and the United Kingdom Schmidt, the InfraRed Astronomical Satellite and the 2 Micron All Sky Survey have proven to be extremely useful tools for astronomy with value that lasts for decades. The Wide-field Infrared Survey Explorer is mapping the whole sky following its launch on 14 December 2009. WISE began surveying the sky on 14 Jan 2010 and completed its first full coverage of the sky on July 17. The survey will continue to cover the sky a second time until the cryogen is exhausted (anticipated in November 2010). WISE is achieving 5 sigma point source sensitivities better than 0.08, 0.11, 1 and 6 mJy in unconfused regions on the ecliptic in bands centered at wavelengths of 3.4, 4.6, 12 and 22 microns. Sensitivity improves toward the ecliptic poles due to denser coverage and lower zodiacal background. The angular resolution is 6.1, 6.4, 6.5 and 12.0 arc-seconds at 3.4, 4.6, 12 and 22 microns, and the astrometric precision for high SNR sources is better than 0.15 arc-seconds., Comment: 22 pages with 19 included figures. Updated to better match the accepted version in the AJ
- Published
- 2010
- Full Text
- View/download PDF
28. First results of the COBE satellite measurement of the anisotropy of the cosmic microwave background radiation
- Author
-
C. Backus, K. Galuk, Samuel H. Moseley, J. Aymon, L. Rokke, G. De Amici, Edward L. Wright, David T. Wilkinson, N. W. Boggess, Samuel Gulkis, L. Tenorio, John C. Mather, Michael A. Janssen, Charles L. Bennett, Robert F. Silverberg, S. Torres, T. L. Murdock, E. S. Cheng, Rainer Weiss, Philip Lubin, T. Kelsall, S. S. Meyer, P. D. Jackson, P. Keegstra, Michael G. Hauser, Richard A. Shafer, A. Kogut, and George F. Smoot
- Subjects
Physics ,Atmospheric Science ,Radiometer ,COSMIC cancer database ,Cosmic microwave background ,Aerospace Engineering ,Astronomy ,Astronomy and Astrophysics ,Cosmology ,Geophysics ,Angular distribution ,Space and Planetary Science ,General Earth and Planetary Sciences ,Satellite ,Anisotropy ,Microwave ,Remote sensing - Abstract
The concept and operation of the Differential Microwave Radiometers (DMR) instrument aboard NASA's Cosmic Background Explorer satellite are reviewed, with emphasis on the software identification and subtraction of potential systematic effects. Preliminary results obtained from the first six months of DMR data are presented, and implications for cosmology are discussed.
- Published
- 1991
29. Early Results From the Cosmic Background Explorer (COBE)
- Author
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David T. Wilkinson, E. S. Cheng, George F. Smoot, S. H. Moseley, N. W. Boggess, T. L. Murdock, Robert F. Silverberg, John C. Mather, T. Kelsall, R. B. Isaacman, S. S. Meyer, G. N. Toller, Charles L. Bennett, Rainer Weiss, Philip Lubin, Robert E. Eplee, Henry Freudenreich, Edward L. Wright, M. Jansssen, M. G. Hauser, Janet L. Weiland, William Spiesman, Samuel Gulkis, Carey M. Lisse, and Rick Shafer
- Subjects
Physics ,Atmospheric Science ,Diffuse Infrared Background Experiment ,media_common.quotation_subject ,Cosmic microwave background ,Cosmic background radiation ,Ecliptic ,Aerospace Engineering ,Dipole anisotropy ,Astronomy ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Galaxy ,Geophysics ,Far infrared ,Space and Planetary Science ,Sky ,Observational cosmology ,General Earth and Planetary Sciences ,Black-body radiation ,Astrophysics::Galaxy Astrophysics ,media_common ,Background radiation - Abstract
The Cosmic Background Explorer, launched November 18, 1989, has nearly completed its first full mapping of the sky with all three of its instruments: a Far Infrared Absolute Spectrophotometer (FIRAS) covering 0.1 to 10 mm, a set of Differential Microwave Radiometers (DMR) operating at 3.3, 5.7, and 9.6 mm, and a Diffuse Infrared Background Experiment (DIRBE) spanning 1 to 300 µm in ten bands. A preliminary map of the sky derived from DIRBE data is presented. Initial cosmological implications include: a limit on the Comptonization y parameter of 10−3, on the chemical potential μ parameter of 10−2, a strong limit on the existence of a hot smooth intergalactic medium, and a confirmation that the dipole anisotropy has the spectrum expected from a Doppler shift of a blackbody. There are no significant anisotropies in the microwave sky detected, other than from our own galaxy and a cosθ dipole anisotropy whose amplitude and direction agree with previous data. At shorter wavelengths, the sky spectrum and anisotropies are dominated by emission from ‘local’ sources of emission within our Galaxy and Solar System. Preliminary comparison of IRAS and DIRBE sky brightnesses toward the ecliptic poles shows the IRAS values to be significantly higher than found by DIRBE at 100 μm. We suggest the presence of gain and zero-point errors in the IRAS total brightness data. The spacecraft, instrument designs, and data reduction methods are described.
- Published
- 1990
30. The Space Infrared Interferometric Telescope (SPIRIT): High-resolution imaging and spectroscopy in the far-infrared
- Author
-
John C. Mather, Anthony J. Martino, Jonathan P. Gardner, Marc J. Kuchner, Lee G. Mundy, Julie A. Crooke, Robert F. Silverberg, Stephen A. Rinehart, Art Ferrer, Amy J. Barger, Dave Quinn, Gordon J. Stacey, Drew Jones, Martin Harwit, Joe Pellicciotti, Paul Mason, Jim Kellogg, Jim Mannion, H. Philip Stahl, Rick Mills, David Leisawitz, Stan Ollendorf, Dominic J. Benford, Lynne A. Hillenbrand, Dave DiPietro, Steve Cooley, Amy Mainzer, Charles Baker, Kate Hartman, Alan J. Kogut, Michael Femiano, John M. Carpenter, Richard Caverly, Phil Chen, Richard Broderick, Javier Lecha, Lou Hallock, Tupper Hyde, Steve Tompkins, Tim Sauerwine, Christine Cottingham, Kenny Harris, Jacqueline Fischer, Andrew Blain, Bill Lawson, Johannes Staguhn, Mike DiPirro, Maria Lecha, Terry Smith, Sheila Wall, Mark E. Wilson, Rob Boyle, Kirk Rhee, Jason Budinoff, Gibran McDonald, and June L. Tveekrem
- Subjects
Atmospheric Science ,Population ,FOS: Physical sciences ,Aerospace Engineering ,Field of view ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,law.invention ,Telescope ,Far infrared ,Planet ,law ,education ,Astrophysics::Galaxy Astrophysics ,Physics ,education.field_of_study ,Astrophysics (astro-ph) ,James Webb Space Telescope ,Astrophysics::Instrumentation and Methods for Astrophysics ,Astronomy ,Astronomy and Astrophysics ,Planetary system ,Atacama Large Millimeter Array ,Geophysics ,Space and Planetary Science ,General Earth and Planetary Sciences ,Astrophysics::Earth and Planetary Astrophysics - Abstract
We report results of a recently-completed pre-Formulation Phase study of SPIRIT, a candidate NASA Origins Probe mission. SPIRIT is a spatial and spectral interferometer with an operating wavelength range 25 - 400 microns. SPIRIT will provide sub-arcsecond resolution images and spectra with resolution R = 3000 in a 1 arcmin field of view to accomplish three primary scientific objectives: (1) Learn how planetary systems form from protostellar disks, and how they acquire their inhomogeneous composition; (2) characterize the family of extrasolar planetary systems by imaging the structure in debris disks to understand how and where planets of different types form; and (3) learn how high-redshift galaxies formed and merged to form the present-day population of galaxies. Observations with SPIRIT will be complementary to those of the James Webb Space Telescope and the ground-based Atacama Large Millimeter Array. All three observatories could be operational contemporaneously., 20 pages, 12 figures, accepted for publication in J. Adv. Space Res. on 26 May 2007
- Published
- 2007
31. On the nature of the sources of the cosmic infrared background
- Author
-
R. G. Arendt, A. Kashlinsky, Samuel H. Moseley, and John C. Mather
- Subjects
media_common.quotation_subject ,Astrophysics::High Energy Astrophysical Phenomena ,Population ,FOS: Physical sciences ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Cosmology ,Cosmic infrared background ,0103 physical sciences ,Astrophysics::Solar and Stellar Astrophysics ,education ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,media_common ,Physics ,Diffuse radiation ,education.field_of_study ,COSMIC cancer database ,010308 nuclear & particles physics ,Astrophysics (astro-ph) ,Astronomy and Astrophysics ,Unit mass ,13. Climate action ,Space and Planetary Science ,Sky ,Astrophysics::Earth and Planetary Astrophysics - Abstract
We discuss interpretation of the cosmic infrared background (CIB) anisotropies detected by us recently in the Spitzer IRAC based measurements. The fluctuations are approximately isotropic on the sky consistent with their cosmological origin. They remain after removal of fairly faint intervening sources and must arise from a population which has a strong CIB clustering component with only a small shot-noise level. We discuss the constraints the data place on the luminosities, epochs and mass-to-light ratios of the indvidual sources producing them. Assuming the concordance LambdaCDM cosmology the measurements imply that the luminous sources producing them lie at cosmic times < 1 Gyr and were individually much brighter per unit mass than the present stellar populations., Ap.J.Letters, in press
- Published
- 2006
32. New measurements of cosmic infrared background fluctuations from early epochs
- Author
-
R. G. Arendt, Samuel H. Moseley, John C. Mather, and A. Kashlinsky
- Subjects
Solar System ,Infrared ,Astrophysics::High Energy Astrophysical Phenomena ,Cosmic background radiation ,FOS: Physical sciences ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Cosmology ,Cosmic infrared background ,0103 physical sciences ,010306 general physics ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Diffuse radiation ,Physics ,COSMIC cancer database ,Astrophysics (astro-ph) ,Astrophysics::Instrumentation and Methods for Astrophysics ,Astronomy ,Astronomy and Astrophysics ,Stars ,13. Climate action ,Space and Planetary Science ,Astrophysics::Earth and Planetary Astrophysics - Abstract
Cosmic infrared background fluctuations may contain measurable contribution from objects inaccessible to current telescopic studies, such as the first stars and other luminous objects in the first Gyr of the Universe's evolution. In an attempt to uncover this contribution we have analyzed the GOODS data obtained with the Spitzer IRAC instrument, which are deeper and cover larger scales than the Spitzer data we have previously analyzed. Here we report these new measurements of the cosmic infrared background (CIB) fluctuations remaining after removing cosmic sources to fainter levels than before. The remaining anisotropies on scales > 0.5 arcmin have a significant clustering component with a low shot-noise contribution. We show that these fluctuations cannot be accounted for by instrumental effects, nor by the Solar system and Galactic foreground emissions and must arise from extragalactic sources., Ap.J.Letters, in press
- Published
- 2006
33. Migration of Comets to the Terrestrial Planets
- Author
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John C. Mather and Sergei I. Ipatov
- Subjects
Physics ,biology ,Astrophysics (astro-ph) ,FOS: Physical sciences ,Astronomy and Astrophysics ,Venus ,Mars Exploration Program ,Astrophysics ,Collision ,biology.organism_classification ,Physics::Geophysics ,Space and Planetary Science ,Planet ,Physics::Space Physics ,Terrestrial planet ,Astrophysics::Earth and Planetary Astrophysics - Abstract
We studied the orbital evolution of Jupiter-family comets (JFCs), Halley-type comets (HTCs), and long-period comets, and probabilities of their collisions with planets. In our runs the probability of a collision of one object with the Earth could be greater than the sum of probabilities for thousands of other objects. Even without a contribution of such a few bodies, the probability of a collision of a former JFC with the Earth was greater than 4$\cdot10^{-6}$. This probability is enough for delivery of all the water to Earth's oceans during formation of the giant planets. The ratios of probabilities of collisions of JFCs and HTCs with Venus and Mars to the mass of a planet usually were not smaller than that for Earth. Among 30,000 considered objects with initial orbits close to those of JFCs, a few objects got Earth-crossing orbits with semi-major axes $a$$, Comment: 10 pages. Paper submitted to Proc. of the IAU Symposium No. 236 "Near Earth Objects, Our Celestial Neighbors: Opportunity and Risk" (Prague, Czech Republic, August 14-18, 2006), edited by A. Milani, G.B. Valsecchi and D. Vokrouhlicky
- Published
- 2006
34. Mission Concept for the Single Aperture Far-Infrared (SAFIR) Observatory
- Author
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David Leisawitz, John C. Mather, S. Harvey Moseley, Dominic J. Benford, and Michael Amato
- Subjects
Physics ,Point source ,Aperture ,media_common.quotation_subject ,James Webb Space Telescope ,Detector ,Astrophysics (astro-ph) ,Astrophysics::Instrumentation and Methods for Astrophysics ,Astronomy ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,law.invention ,Telescope ,Space and Planetary Science ,Sky ,law ,Observatory ,Angular resolution ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics::Galaxy Astrophysics ,media_common - Abstract
The Single Aperture Far-InfraRed (SAFIR) Observatory's science goals are driven by the fact that the earliest stages of almost all phenomena in the universe are shrouded in absorption by and emission from cool dust and gas that emits strongly in the far-infrared and submillimeter. Over the past several years, there has been an increasing recognition of the critical importance of this spectral region to addressing fundamental astrophysical problems, ranging from cosmological questions to understanding how our own Solar System came into being. The development of large, far-infrared telescopes in space has become more feasible with the combination of developments for the James Webb Space Telescope and of enabling breakthroughs in detector technology. We have developed a preliminary but comprehensive mission concept for SAFIR, as a 10 m-class far-infrared and submillimeter observatory that would begin development later in this decade to meet the needs outlined above. Its operating temperature (, 36 pages
- Published
- 2005
- Full Text
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35. Detecting Population III stars through observations of near-IR cosmic infrared background anisotropies
- Author
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A. Kashlinsky, R. G. Arendt, John C. Mather, S. Harvey Moseley, and Jonathan P. Gardner
- Subjects
Physics ,education.field_of_study ,Epoch (astronomy) ,Metallicity ,media_common.quotation_subject ,Astrophysics (astro-ph) ,Population ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,CMB cold spot ,Galaxy ,Universe ,Stars ,Space and Planetary Science ,Cosmic infrared background ,Astrophysics::Solar and Stellar Astrophysics ,Astrophysics::Earth and Planetary Astrophysics ,education ,Astrophysics::Galaxy Astrophysics ,media_common - Abstract
Following the successful mapping of the last scattering surface by WMAP and balloon experiments, the epoch of the first stars, when Population III stars formed, is emerging as the next cosmological frontier. It is not clear what these stars' properties were, when they formed or how long their era lasted before leading to the stars and galaxies we see today. We show that these questions can be answered with the current and future measurements of the near-IR cosmic infrared background (CIB). Theoretical arguments suggest that Population III stars were very massive and short-lived stars that formed at $z\sim 10-20$ at rare peaks of the density field in the cold-dark-matter Universe. Because Population III stars probably formed individually in small mini-halos, they are not directly accessible to current telescopic studies. We show that these stars left a strong and measurable signature via their contribution to the CIB anisotropies for a wide range of their formation scenarios. The excess in the recently measured near-IR CIB anisotropies over that from normal galaxies can be explained by contribution from early Population III stars. These results imply that Population III were indeed very massive stars and their epoch started at $z\sim 20$ and lasted past $z\lsim 13$. We show the importance of accurately measuring the CIB anisotropies produced by Population III with future space-based missions., Ap.J., in press. (Replaced with accepted version)
- Published
- 2004
36. Migration of Small Bodies and Dust to Near-Earth Space
- Author
-
Sergei I. Ipatov and John C. Mather
- Subjects
Physics ,Atmospheric Science ,Zodiacal light ,Comet dust ,Astrophysics (astro-ph) ,Aerospace Engineering ,Astronomy ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Astrobiology ,Jupiter ,Geophysics ,Interplanetary dust cloud ,Space and Planetary Science ,Planet ,Saturn ,Physics::Space Physics ,Astrophysics::Solar and Stellar Astrophysics ,General Earth and Planetary Sciences ,Circumstellar dust ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics::Galaxy Astrophysics ,Cosmic dust - Abstract
The orbital evolution of Jupiter-family comets (JFCs), resonant asteroids, and asteroidal, trans-Neptunian, and cometary dust particles under the gravitational influence of planets was integrated. For dust particles we also considered radiation pressure, Poynting-Robertson drag, and solar wind drag. The probability of a collision of one former JFC with a terrestrial planet can be greater than analogous total probability for thousands other JFCs. If those former JFCs that got near-Earth object (NEO) orbits for millions of years didn't disintegrate during this time, there could be many extinct comets among NEOs. The maximum probability of a collision of an asteroidal or cometary dust particle with the Earth during its lifetime was for diameter $d$$\sim$100 microns. At $d$$, Comment: Submitted to Advances in Space Research (Proceedings of COSPAR-2004)
- Published
- 2004
- Full Text
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37. Migration of Trans-Neptunian Objects to the Terrestrial Planets
- Author
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Sergei I. Ipatov and John C. Mather
- Subjects
Orbital elements ,Physics ,Solar System ,Comet ,Astrophysics (astro-ph) ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Gravitation ,Space and Planetary Science ,Planet ,Physics::Space Physics ,Earth and Planetary Sciences (miscellaneous) ,Orbit (dynamics) ,Terrestrial planet ,Trans-Neptunian object ,Astrophysics::Earth and Planetary Astrophysics - Abstract
The orbital evolution of more than 22000 Jupiter-crossing objects under the gravitational influence of planets was investigated. We found that the mean collision probabilities of Jupiter-crossing objects (from initial orbits close to the orbit of a comet) with the terrestrial planets can differ by more than two orders of magnitude for different comets. For initial orbital elements close to those of some comets (e.g. 2P and 10P), about 0.1% of objects got Earth-crossing orbits with semi-major axes a, Earth, Moon, and Planets [Proceedings of the international scientific workshop on the "First Decadal Review of the Edgeworth-Kuiper Belt - Towards New Frontiers" (11-14 March 2003, Antofagasta, Chile)]. In press
- Published
- 2003
- Full Text
- View/download PDF
38. Comet and Asteroid Hazard to the Terrestrial Planets
- Author
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Sergei I. Ipatov and John C. Mather
- Subjects
Orbital elements ,Physics ,Atmospheric Science ,Aphelia ,biology ,Comet ,Astrophysics (astro-ph) ,Aerospace Engineering ,FOS: Physical sciences ,Astronomy and Astrophysics ,Venus ,Astrophysics ,biology.organism_classification ,Jupiter ,Geophysics ,Space and Planetary Science ,Asteroid ,Physics::Space Physics ,Orbit (dynamics) ,General Earth and Planetary Sciences ,Terrestrial planet ,Astrophysics::Earth and Planetary Astrophysics - Abstract
We estimated the rate of comet and asteroid collisions with the terrestrial planets by calculating the orbits of 13000 Jupiter-crossing objects (JCOs) and 1300 resonant asteroids and computing the probabilities of collisions based on random-phase approximations and the orbital elements sampled with a 500 yr step. The Bulirsh-Stoer and a symplectic orbit integrator gave similar results for orbital evolution, but may give different collision probabilities with the Sun. A small fraction of former JCOs reached orbits with aphelia inside Jupiter's orbit, and some reached Apollo orbits with semi-major axes less than 2 AU, Aten orbits, and inner-Earth orbits (with aphelia less than 0.983 AU) and remained there for millions of years. Though less than 0.1% of the total, these objects were responsible for most of the collision probability of former JCOs with Earth and Venus. We conclude that a significant fraction of near-Earth objects could be extinct comets that came from the trans-Neptunian region., "Advances in Space Research" (Proc. of COSPAR-2002 (10-19 October 2002, Houston, TX, USA), COSPAR02-A-00845), final text
- Published
- 2002
39. Signatures of exosolar planets in dust debris disks
- Author
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Nick Gorkavyi, John C. Mather, Tanya Taidakova, and Leonid M. Ozernoy
- Subjects
Physics ,Orbital elements ,Scattering ,Astrophysics (astro-ph) ,Vega ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Exoplanet ,Gravitation ,Space and Planetary Science ,Planet ,Circumstellar dust ,Astrophysics::Solar and Stellar Astrophysics ,Astrophysics::Earth and Planetary Astrophysics ,James Clerk Maxwell Telescope ,Astrophysics::Galaxy Astrophysics - Abstract
We apply our recently elaborated, powerful numerical approach to the high-resolution modeling of the structure and emission of circumstellar dust disks, incorporating all relevant physical processes. Specifically, we examine the resonant structure of a dusty disk induced by the presence of one planet. It is shown that the planet, via resonances and gravitational scattering, produces (1) an asymmetric resonant dust belt with one or more clumps intermittent with one or a few off-center cavities; and (2) a central cavity void of dust. These features can serve as indicators of a planet embedded in the circumstellar dust disk and, moreover, can be used to determine its major orbital parameters and even the mass of the planet. The results of our study reveal a remarkable similarity with various types of highly asymmetric circumstellar disks observed with the James Clerk Maxwell Telescope around Epsilon Eridani and Vega. The proposed interpretation of the clumps in those disks as being resonant patterns is testable -- it predicts the asymmetric design around the star to revolve, viz., by 1.2--1.6 deg/yr about Vega and 0.6--0.8 deg/yr about Epsilon Eri., to be published in ApJ Letters (v. 537, July 10, 2000), 5 pages, incl. 2 figures. Position of (color) Fig. 2 corrected to make the Figure caption fully readable
- Published
- 2000
40. Clustering of the Diffuse Infrared Light from the COBE DIRBE maps. III. Power spectrum analysis and excess isotropic component of fluctuations
- Author
-
S. Odenwald, A. Kashlinsky, and John C. Mather
- Subjects
Physics ,Astrophysics (astro-ph) ,Center (category theory) ,FOS: Physical sciences ,Spectral density ,Astronomy and Astrophysics ,Astrophysics ,Galactic plane ,Galaxy ,Stars ,Amplitude ,Space and Planetary Science ,Cosmic infrared background ,Energy (signal processing) - Abstract
The cosmic infrared background (CIB) radiation is the cosmic repository for energy release throughout the history of the universe. Using the all-sky data from the COBE DIRBE instrument at wavelengths 1.25 - 100 mic we attempt to measure the CIB fluctuations. In the near-IR, foreground emission is dominated by small scale structure due to stars in the Galaxy. There we find a strong correlation between the amplitude of the fluctuations and Galactic latitude after removing bright foreground stars. Using data outside the Galactic plane ($|b| > 20\deg$) and away from the center ($90\deg< l, Comment: Ap.J., in press. 69 pages including 24 figs
- Published
- 1999
41. The COBE Diffuse Infrared Background Experiment Search for the Cosmic Infrared Background: I. Limits and Detections
- Author
-
David T. Wilkinson, R. G. Arendt, William T. Reach, Janet L. Weiland, Robert F. Silverberg, H. T. Freudenreich, Michael G. Hauser, John C. Mather, N. Odegard, T. Kelsall, Richard A. Shafer, E. Dwek, Edward L. Wright, George F. Smoot, Y. C. Pei, Rainer Weiss, Philip Lubin, and Samuel H. Moseley
- Subjects
Physics ,Diffuse Infrared Background Experiment ,Hubble Deep Field ,Cosmic microwave background ,Astrophysics (astro-ph) ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Redshift ,Galaxy ,Interplanetary dust cloud ,Space and Planetary Science ,Cosmic infrared background ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics::Galaxy Astrophysics ,Cosmic dust - Abstract
The DIRBE on the COBE spacecraft was designed primarily to conduct systematic search for an isotropic CIB in ten photometric bands from 1.25 to 240 microns. The results of that search are presented here. Conservative limits on the CIB are obtained from the minimum observed brightness in all-sky maps at each wavelength, with the faintest limits in the DIRBE spectral range being at 3.5 microns (\nu I_\nu < 64 nW/m^2/sr, 95% CL) and at 240 microns (\nu I_\nu < 28 nW/m^2/sr, 95% CL). The bright foregrounds from interplanetary dust scattering and emission, stars, and interstellar dust emission are the principal impediments to the DIRBE measurements of the CIB. These foregrounds have been modeled and removed from the sky maps. Assessment of the random and systematic uncertainties in the residuals and tests for isotropy show that only the 140 and 240 microns data provide candidate detections of the CIB. The residuals and their uncertainties provide CIB upper limits more restrictive than the dark sky limits at wavelengths from 1.25 to 100 microns. No plausible solar system or Galactic source of the observed 140 and 240 microns residuals can be identified, leading to the conclusion that the CIB has been detected at levels of \nu I_\nu = 25+-7 and 14+-3 nW/m^2/sr at 140 and 240 microns respectively. The integrated energy from 140 to 240 microns, 10.3 nW/m^2/sr, is about twice the integrated optical light from the galaxies in the Hubble Deep Field, suggesting that star formation might have been heavily enshrouded by dust at high redshift. The detections and upper limits reported here provide new constraints on models of the history of energy-releasing processes and dust production since the decoupling of the cosmic microwave background from matter., Comment: 26 pages and 5 figures, accepted for publication in the Astrophyical Journal
- Published
- 1998
42. The Spectrum of the Extragalactic Far Infrared Background from the COBE Firas Observations
- Author
-
E. Dwek, John C. Mather, D. J. Fixsen, Richard A. Shafer, and Charles L. Bennett
- Subjects
Physics ,Astrophysics (astro-ph) ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Lambda ,Spectral line ,Far infrared ,Planck's law ,Space and Planetary Science ,Nucleosynthesis ,Intensity (heat transfer) ,Energy (signal processing) ,Cosmic dust - Abstract
The COBE FIRAS data contain foreground emission from interplanetary, Galactic interstellar dust and extragalactic background emission. We use three different methods to separate the various emission components, and derive the spectrum of the extragalactic Far InfraRed Background (FIRB). Each method relies on a different set of assumptions, which affect the FIRB spectrum in different ways. Despite this, the FIRB spectra derived by these different methods are remarkably similar. The average spectrum that we derive in the \nu = 5 - 80 cm^{-1} (2000-125 \um) frequency interval is: I(\nu) = (1.3 \pm 0.4)\times10^{-5} (\nu /\nu_0)^{0.64 \pm 0.12} P_{\nu}(18.5 \pm 1.2 K), where \nu_0=100 cm^{-1} (\lambda_0=100 \um) and P is the Planck function. The derived FIRB spectrum is consistent with the DIRBE 140 and 240 \um detections. The total intensity received in the 5 - 80 cm^{-1} frequency interval is 14 nW m^{-2} sr^{-1}, and comprises about 20% of the total intensity expected from the energy release from nucleosynthesis throughout the history of the universe., Comment: 12 pages Latex (AAS macro), 4 Postscript figures, accepted by The Astrophysical Journal
- Published
- 1998
43. Calibrator Design for the COBE Far Infrared Absolute Spectrophotometer (FIRAS)
- Author
-
John C. Mather, D. J. Fixsen, C. Mosier, Richard A. Shafer, and David T. Wilkinson
- Subjects
Physics ,Brightness ,Observational error ,Far infrared ,Space and Planetary Science ,Cosmic microwave background ,Astrophysics (astro-ph) ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Temperature measurement ,Beam (structure) - Abstract
The photometric errors of the external calibrator for the FIRAS instrument on the COBE are smaller than the measurement errors on the cosmic microwave background (CMBR) spectrum (typically 0.02 MJy/sr, 1 sigma), and smaller than 0.01% of the peak brightness of the CMBR. The calibrator is a re-entrant cone, shaped like a trumpet mute, made of Eccosorb iron-loaded epoxy. It fills the entire beam of the instrument and is the source of its accuracy. Its known errors are caused by reflections, temperature gradients, and leakage through the material and around the edge. Estimates and limits are given for all known error sources. Improvements in understanding the temperature measurements of the calibrator allow an improved CMBR temperature determination of 2.725 +/- 0.002 K., Comment: 30 pages, 9 Postscript figures, uses aasms4.sty, ApJ, 1999, 512, xxx
- Published
- 1998
- Full Text
- View/download PDF
44. Comparison of the COBE FIRAS and DIRBE Calibrations
- Author
-
Richard A. Shafer, T. Kelsall, K. A. Jensen, Robert F. Silverberg, S. Brodd, J. L. Weiland, Michael G. Hauser, David Leisawitz, John C. Mather, and D. J. Fixsen
- Subjects
Physics ,Cross Calibration ,Offset (computer science) ,Space and Planetary Science ,Wavelength range ,Astrophysics (astro-ph) ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics - Abstract
We compare the independent FIRAS and DIRBE observations from the COBE in the wavelength range 100-300 microns. This cross calibration provides checks of both data sets. The results show that the data sets are consistent within the estimated gain and offset uncertainties of the two instruments. They show the possibility of improving the gain and offset determination of DIRBE at 140 and 240 microns., Accepted for publication in the Astrophysical Journal 11 pages, plus 3 figures in separate postscript files. Figure 3 has three parts
- Published
- 1997
45. CROSS-CORRELATING COSMIC INFRARED AND X-RAY BACKGROUND FLUCTUATIONS: EVIDENCE OF SIGNIFICANT BLACK HOLE POPULATIONS AMONG THE CIB SOURCES
- Author
-
A. Kashlinsky, A. Finoguenov, G. G. Fazio, Andrea Comastri, G. Hasinger, R. G. Arendt, S. H. Moseley, Nico Cappelluti, Takamitsu Miyaji, and John C. Mather
- Subjects
Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,Active galactic nucleus ,Astrophysics::High Energy Astrophysical Phenomena ,media_common.quotation_subject ,X-ray background ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,01 natural sciences ,Cosmic infrared background ,0103 physical sciences ,010306 general physics ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,media_common ,High Energy Astrophysical Phenomena (astro-ph.HE) ,Physics ,COSMIC cancer database ,Accretion (meteorology) ,Astronomy and Astrophysics ,Galaxy ,Black hole ,13. Climate action ,Space and Planetary Science ,Sky ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics - High Energy Astrophysical Phenomena ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
In order to understand the nature of the sources producing the recently uncovered cosmic infrared background (CIB) fluctuations, we study cross-correlations between the fluctuations in the source-subtracted CIB from Spitzer/IRAC data and the unresolved cosmic X-ray background from deep Chandra observations. Our study uses data from the EGS/AEGIS field, where both data sets cover an 8'x45' region of the sky. Our measurement is the cross-power spectrum between the IR and X-ray data. The cross-power signal between the IRAC maps at 3.6 um and 4.5 um and the Chandra [0.5-2] keV data has been detected, at angular scales 20'', with an overall significance of 3.8 sigma and 5.6 sigma, respectively. At the same time we find no evidence of significant cross-correlations at the harder Chandra bands. The cross-correlation signal is produced by individual IR sources with 3.6 um and 4.5 um magnitudes m_AB 25-26 and [0.5-2] keV X-ray fluxes 7e-17 cgs.We determine that at least 15%-25% of the large scale power of the CIB fluctuations is correlated with the spatial power spectrum of the X-ray fluctuations. If this correlation is attributed to emission from accretion processes at both IR and X-ray wavelengths, this implies a much higher fraction of accreting black holes than among the known populations. We discuss the various possible origins for the cross-power signal and show that neither local foregrounds nor the known remaining normal galaxies and active galactic nuclei can reproduce the measurements. These observational results are an important new constraint on theoretical modeling of the near-IR CIB fluctuations., 28 pages, 9 Figures, Accepted by ApJ
- Published
- 2013
46. Clustering of the Diffuse Infrared Light from the COBE DIRBE maps. I. $C(0)$ and limits on the near-IR background
- Author
-
M. G. Hauser, A. Kashlinsky, John C. Mather, and S. Odenwald
- Subjects
Physics ,Space and Planetary Science ,Infrared ,Near-infrared spectroscopy ,Astrophysics (astro-ph) ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Cluster analysis - Abstract
This paper is devoted to studying the CIB through its correlation properties. We studied the limits on CIB anisotropy in the near IR (1.25, 2.2, and 3.5 \um, or $J,\;K,\;L$) bands at a scale of 0.7\deg\ using the COBE\footnote{ The National Aeronautics and Space Administration/Goddard Space Flight Center (NASA/GSFC) is responsible for the design, development, and operation of the {\it COBE}. Scientific guidance is provided by the {\it COBE} Science Working Group. GSFC is also responsible for the development of the analysis software and for the production of the mission data sets.} Diffuse Infrared Background Experiment (DIRBE) data. In single bands we obtain the upper limits on the zero-lag correlation signal $C(0)= \langle(\nu \delta I_\nu)^2\rangle < 3.6 \times 10^{-16},\; 5.1 \times 10^{-17},\; 5.7 \times 10^{-18}$ \w2m4sr2 for the $J,K,L$ bands respectively. The DIRBE data exhibit a clear color between the various bands with a small dispersion. On the other hand most of the CIB is expected to come from redshifted galaxies and thus should have different color properties. We use this observation to develop a `color subtraction' method of linear combinations of maps at two different bands. This method is expected to suppress the dominant fluctuations from foreground stars and nearby galaxies, while not reducing (or perhaps even amplifying) the extragalactic contribution to $C(0)$. Applying this technique gives significantly lower and more isotropic limits., Comment: 44 pages postcript; includes 5 tables, 14 figures. Astrophysical Journal, in press
- Published
- 1996
- Full Text
- View/download PDF
47. The Cosmic Microwave Background Spectrum from the Full COBE/FIRAS Data Set
- Author
-
Richard A. Shafer, J.M. Gales, D. J. Fixsen, Edward L. Wright, Edward Cheng, and John C. Mather
- Subjects
Physics ,COSMIC cancer database ,Astrophysics::High Energy Astrophysical Phenomena ,Spectrum (functional analysis) ,Cosmic microwave background ,Astrophysics (astro-ph) ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Dipole ,Amplitude ,Far infrared ,Space and Planetary Science ,Black-body radiation ,Absolute zero - Abstract
We have refined the analysis of the data from the FIRAS (Far InfraRed Absolute Spectrophotometer) on board the COBE (COsmic Background Explorer). The FIRAS measures the difference between the cosmic microwave background and a precise blackbody spectrum. We find new tighter upper limits on general deviations from a blackbody spectrum. The RMS deviations are less than 50 parts per million of the peak of the CMBR. For the Comptonization and chemical potential we find $|y| < 15\times10^{-6}$ and $|��| < 9\times10^{-5}$ (95\% CL). There are also refinements in the absolute temperature, 2.728 $\pm$ 0.004 K (95\% CL), and dipole direction, $(\ell,b)=(264.14^\circ\pm0.30, 48.26^\circ\pm0.30)$ (95\% CL), and amplitude, $3.372 \pm 0.007$ mK (95\% CL). All of these results agree with our previous publications., 32 pages, LaTeX+aasms package, 6 figures as separate PostScript file. Submitted to Ap.J
- Published
- 1996
- Full Text
- View/download PDF
48. NEW MEASUREMENTS OF THE COSMIC INFRARED BACKGROUND FLUCTUATIONS IN DEEPSPITZER/IRAC SURVEY DATA AND THEIR COSMOLOGICAL IMPLICATIONS
- Author
-
Giovanni G. Fazio, Samuel H. Moseley, A. Kashlinsky, Matthew L. N. Ashby, John C. Mather, and R. G. Arendt
- Subjects
Physics ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,Zodiacal light ,media_common.quotation_subject ,Shot noise ,FOS: Physical sciences ,Astronomy and Astrophysics ,Lambda-CDM model ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Galaxy ,Stars ,Space and Planetary Science ,Sky ,Cosmic infrared background ,Astrophysics::Galaxy Astrophysics ,Noise (radio) ,Astrophysics - Cosmology and Nongalactic Astrophysics ,media_common - Abstract
We extend previous measurements of cosmic infrared background (CIB) fluctuations to ~ 1 deg using new data from the Spitzer Extended Deep Survey. Two fields, with depths of ~12 hr/pixel over 3 epochs, are analyzed at 3.6 and 4.5 mic. Maps of the fields were assembled using a self-calibration method uniquely suitable for probing faint diffuse backgrounds. Resolved sources were removed from the maps to a magnitude limit of AB mag ~ 25, as indicated by the level of the remaining shot noise. The maps were then Fourier-transformed and their power spectra were evaluated. Instrumental noise was estimated from the time-differenced data, and subtracting this isolates the spatial fluctuations of the actual sky. The power spectra of the source-subtracted fields remain identical (within the observational uncertainties) for the three epochs indicating that zodiacal light contributes negligibly to the fluctuations. Comparing to 8 mic power spectra shows that Galactic cirrus cannot account for the fluctuations. The signal appears isotropically distributed on the sky as required for an extragalactic origin. The CIB fluctuations continue to diverge to > 10 times those of known galaxy populations on angular scales out to < 1 deg. The low shot noise levels remaining in the diffuse maps indicate that the large scale fluctuations arise from the spatial clustering of faint sources well below the confusion noise. The spatial spectrum of these fluctuations is in reasonable agreement with an origin in populations clustered according to the standard cosmological model (LCDM) at epochs coinciding with the first stars era., ApJ, to be published
- Published
- 2012
49. Erratum: 'New Measurements of Cosmic Infrared Background Fluctuations from Early Epochs' ([URL ADDRESS='/cgi-bin/resolve?2007ApJ...654L...5K' STATUS='OKAY']ApJ 655, L5 [2007][/URL])
- Author
-
A. Kashlinsky, S. H. Moseley, John C. Mather, and R. G. Arendt
- Subjects
Physics ,010308 nuclear & particles physics ,Space and Planetary Science ,Cosmic infrared background ,0103 physical sciences ,Astronomy ,Astronomy and Astrophysics ,010306 general physics ,01 natural sciences - Published
- 2007
50. Far-Infrared Spectral Observations of the Galaxy by COBE
- Author
-
Edward L. Wright, Eli Dwek, William T. Reach, Tilak Hewagama, John C. Mather, L. P. Rosen, S. M. Read, Charles L. Bennett, Edward Cheng, R. E. Eplee, A. J. Banday, George F. Smoot, T. J. Sodroski, F. G. D. Shuman, Richard A. Shafer, David Leisawitz, Dale J. Fixsen, and Philip Lubin
- Subjects
Physics ,Molecular cloud ,Astrophysics (astro-ph) ,Cosmic microwave background ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Galaxy ,Spectral line ,Far infrared ,Space and Planetary Science ,Sky brightness ,Emissivity ,Astrophysics::Galaxy Astrophysics ,Cosmic dust - Abstract
We derive Galactic continuum spectra from 5-96/cm from COBE/FIRAS observations. The spectra are dominated by warm dust emission, which may be fit with a single temperature in the range 16-21 K (for nu^2 emissivity) along each line of sight. Dust heated by the attenuated radiation field in molecular clouds gives rise to intermediate temperature (10-14 K) emission in the inner Galaxy only. A widespread, very cold component (4-7 K) with optical depth that is spatially correlated with the warm component is also detected. The cold component is unlikely to be due to very cold dust shielded from starlight, because it is present at high latitude. We consider hypotheses that the cold component is due to enhanced submillimeter emissivity of the dust that gives rise to the warm component, or that it may be due to very small, large, or fractal particles. Lack of substantial power above the emission from warm dust places strong constraints on the amount of cold gas in the Galaxy. The microwave sky brightness due to interstellar dust is dominated by the cold component, and its angular variation could limit our ability to discern primordial fluctuations in the cosmic microwave background radiation., Comment: UUencoded tar file, including LaTeX manuscript file and 11 postscript figure files; accepted for publication in the Astrophysical Journal, scheduled for 20 Sep 1995 issue
- Published
- 1995
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