DOCSLIB.ORG

Extrapolation of Galactic Dust Emission at 100 Microns to Cosmic Microwave Background Radiation Frequencies Using FIRAS

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Extrapolation of Galactic Dust Emission at 100 Microns to Cosmic Microwave Background Radiation Frequencies Using FIRAS Extrapolation of Galactic Dust Emission at 100 Microns to Cosmic Microwave Background Radiation Frequencies Using FIRAS The Harvard community has made this article openly available. Please share how this access benefits you. Your story matters Citation Finkbeiner, Douglas P., Marc Davis, and David J. Schlegel. 1999. “Extrapolation of Galactic Dust Emission at 100 Microns to Cosmic Microwave Background Radiation Frequencies Using FIRAS.” The Astrophysical Journal 524 (2) (October 20): 867–886. doi:10.1086/307852. Published Version 10.1086/307852 Citable link http://nrs.harvard.edu/urn-3:HUL.InstRepos:33462888 Terms of Use This article was downloaded from Harvard University’s DASH repository, and is made available under the terms and conditions applicable to Other Posted Material, as set forth at http:// nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of- use#LAA THE ASTROPHYSICAL JOURNAL, 524:867È886, 1999 October 20 ( 1999. The American Astronomical Society. All rights reserved. Printed in U.S.A. EXTRAPOLATION OF GALACTIC DUST EMISSION AT 100 MICRONS TO COSMIC MICROWAVE BACKGROUND RADIATION FREQUENCIES USING FIRAS DOUGLAS P. FINKBEINER AND MARC DAVIS University of California at Berkeley, Departments of Physics and Astronomy, 601 Campbell Hall, Berkeley, CA 94720; dÐnk=astro.berkeley.edu, marc=deep.berkeley.edu AND DAVID J. SCHLEGEL Princeton University, Department of Astrophysics, Peyton Hall, Princeton, NJ 08544; schlegel=astro.princeton.edu Received 1999 March 5; accepted 1999 June 8 ABSTRACT We present predicted full-sky maps of submillimeter and microwave emission from the di†use inter- stellar dust in the Galaxy. These maps are extrapolated from the 100 km emission and 100/240 km Ñux ratio maps that Schlegel, Finkbeiner, & Davis generated from IRAS and COBE/DIRBE data. Results are presented for a number of physically plausible emissivity models. The correlation of COBE/FIRAS data with the simple Schlegel, Finkbeiner, & Davis (l2 emissivity power law) extrapolation is much tighter than with other common dust templates such as H I column density or 100 km emission. Despite the apparent success of the Schlegel, Finkbeiner, & Davis extrapolation, the assumed l2 emissivity is inconsistent with the FIRAS data below 800 GHz. Indeed, no power-law emissivity function Ðts the FIRAS data from 200 to 2100 GHz. In this paper we provide a formalism for a multicomponent model for the dust emission. A two-component model with a mixture of ““ silicate ÏÏ and ““ carbon-dominated ÏÏ grains (motivated by Pollack et al.) provides a Ðt to an accuracy of D15% to all the FIRAS data over the entire high-latitude sky. Small systematic di†erences are found between the atomic and molecular phases of the ISM. COBE/DMR has observed microwave emission that is correlated with thermal dust emission. However, this emission is higher than our model predicts by factors of 1.2, 2.4, and 20 at 90, 53, and 31 GHz, respectively. This provides evidence that another emission mechanism dominates dust emission at frequencies below D60 GHz. Our predictions for the thermal (vibrational) emission from Galactic dust at l\3000 GHz are available for general use. These full-sky predictions can be made at the DIRBE resolution of 40@ or at the higher resolution of6.1@ from the Schlegel, Finkbeiner, & Davis DIRBE-corrected IRAS maps. Subject headings: dust, extinction È infrared: ISM: continuum È submillimeter INTRODUCTION 1. In this paper, we consider the use of the SFD98 dust map The pioneering Infrared Astronomy Satellite (IRAS) led as a predictor for microwave emission from Galactic dust. to the discovery of the ubiquitous infrared cirrus, whose The SFD98 map is based solely upon 100È240 km (1250È thermal emission is especially visible in the 100 km band 3000 GHz) emission. Extrapolation to microwave fre- (Low et al. 1984). This cirrus, with a characteristic tem- quencies is very sensitive to the details of the composition perature of D20 K, arches across the sky in long Ðlamen- and emissivity properties of the dust. We show that the l2 tary chains and is present at all Galactic latitudes. However, emissivity assumed by SFD98 is inconsistent with the 100È IRAS was optimized for the detection of point sources, and 2100 GHz emission probed by the COBE Far Infrared its ability to map the di†use cirrus was less than optimal. Absolute Spectrophotometer (FIRAS). We use these FIRAS Because of calibration drifts and hysteresis e†ects, the data to constrain the properties of the dust and show that resulting IRAS Sky Survey Atlas (ISSA: Wheelock et al. no power-law emissivity model can consistently explain the 1994) images are contaminated by signiÐcant striping and full spectral range of the dust emission. However, we Ðnd poor control of large-scale gradients. excellent agreement with a two-component model whose The Di†use Infrared Background Experiment (DIRBE) components we tentatively refer to as silicate- and carbon- on the COBE satellite is the perfect complement to IRAS.It dominated grains. With this model for the dust emissivity has relatively low angular resolution(0¡.7) but superbly con- function, extrapolation of Galactic dust emission from 100 trolled zero points and gains. This has led to the generation km to lower frequencies is based upon the Ðltered DIRBE of a map of the far-infrared sky with unprecedented accu- 100/240 km color temperature. racy and uniformity of coverage. Schlegel, Finkbeiner, & In ° 2, we discuss the COBE data sets and the details of Davis (1998, hereafter SFD98) created a merged map of the comparisons using SFD98. Section 3 explores a variety of IRAS and DIRBE data with an angular resolution of 6@ and one-component dust models, demonstrating that a single DIRBE-quality calibration. Their full-sky map shows the power-law emissivity fails to explain the data, as does a pervasive extent of the infrared cirrus and has proved suc- broadened temperature distribution. Section 4 explores a cessful for estimation of extragalactic reddening. But family of two-component dust models, in which energy equally important will be the use of this type of data for balance and the temperature of the separate components estimation of Galactic foreground for the coming gener- are tightly coupledÈone of which achieves excellent agree- ation of CMBR experiments, including MAP and Planck ment with the FIRAS data. Section 5 discusses the robust- and a host of ground- and balloon-based projects. ness of this best model with respect to various ISM 867 868 FINKBEINER ET AL. Vol. 524 environments, and °6 compares our predictions to (DMR) of 123 frequency bins at 100 \l\2100 GHz (140 microwave observations, demonstrating that the micro- km \j\3 mm). Note that data in the lowest two fre- wave emission may exceed the predictions of any thermal quency bins are o† the page in some of the Ðgures but are (vibrational) emission mechanisms. This is perhaps the sig- used in the Ðts. nature of spinning dust grains emitting electric dipole radi- ation (Draine & Lazarian 1998b) or the signature of 2.2. DMR Data free-free emission. Summary and conclusions are presented DMR observed the sky at three frequencies, 31.5, 53, and in ° 7. Details of the frequency bin choice and recalibration 90 GHz, achieving the Ðrst detection of anisotropy in the can be found in Appendix A. Appendix B contains details CMBR (Smoot et al. 1992). In this paper we use the 4-Year on computational methods, and Appendix C provides DMR Skymaps dated 1995 April 18, which have the mono- details on data presentation. pole and dipole removed. These maps do not inÑuence any of our model Ðts, but are compared with our predictions in 2. DATA SETS ° 6. Kogut et al. (1996) observed a correlation between Galac- The COBE (COsmic Background Explorer) satellite con- tic dust and the 31.5 and 53 GHz channels of DMR that is sisted of three instruments, DMR (Di†erential Microwave much greater than that expected from any models of Radiometer), FIRAS (Far Infrared Absolute thermal (vibrational) emission by dust. Alternative explana- Spectrophotometer), and DIRBE (Di†use Infrared Back- tions such as spinning dust grains (Draine & Lazarian ground Experiment). In this paper we shall compare predic- 1998b) or spatially correlated free-free emission have been tions of dust emission based on DIRBE in the far-infrared proposed but are not well constrained by existing data (cf. with that observed by FIRAS at lower frequencies. In addi- de Oliveira-Costa et al. 1998). We discuss this excess emis- tion, we extend this correlation to still lower frequencies sion in ° 6. (31.5, 53, and 90 GHz) observed by DMR. Although the DMR Ñuctuations are dominated by intrinsic CMBR 2.3. DIRBE Data and SFD Dust Maps anisotropy, a residual correlation with DIRBE is detectable 2.3.1. SFD Emission Map even at high latitudes. SFD98 presented a full-sky 100 km cirrus emission map constructed from both the DIRBE and IRAS/ISSA data 2.1. FIRAS Spectra sets. The map is well calibrated, zodiacal lightÈsubtracted, The objective of the FIRAS instrument was to compare Fourier-destriped, and point sourceÈsubtracted, with a Ðnal the cosmic microwave background radiation (CMBR) to an resolution of6.1.@ Complete descriptions of these maps may accurate blackbody and to observe the dust and line emis- be found in SFD98.2 For comparisons with FIRAS and sion from the Galaxy. It is a polarizing Michelson interfer- DMR, the full resolution of the IRAS/DIRBE map is not ometer (Mather 1982), operated di†erentially with an required. Instead, we use the0¡.7 DIRBE map with zodiacal internal reference blackbody and calibrated by an external light removed as described in SFD98, with point sources blackbody with an emissivity known to better than one part included.
Load more

Recommended publications
  • Detection of Polarization in the Cosmic Microwave Background Using DASI
    Detection of Polarization in the Cosmic Microwave Background using DASI Thesis by John M. Kovac A Dissertation Submitted to the Faculty of the Division of the Physical Sciences in Candidacy for the Degree of Doctor of Philosophy The University of Chicago Chicago, Illinois 2003 Copyright c 2003 by John M. Kovac ° (Defended August 4, 2003) All rights reserved Acknowledgements Abstract This is a sample acknowledgement section. I would like to take this opportunity to The past several years have seen the emergence of a new standard cosmological model thank everyone who contributed to this thesis. in which small temperature di®erences in the cosmic microwave background (CMB) I would like to take this opportunity to thank everyone. I would like to take on degree angular scales are understood to arise from acoustic oscillations in the hot this opportunity to thank everyone. I would like to take this opportunity to thank plasma of the early universe, sourced by primordial adiabatic density fluctuations. In everyone. the context of this model, recent measurements of the temperature fluctuations have led to profound conclusions about the origin, evolution and composition of the uni- verse. Given knowledge of the temperature angular power spectrum, this theoretical framework yields a prediction for the level of the CMB polarization with essentially no free parameters. A determination of the CMB polarization would therefore provide a critical test of the underlying theoretical framework of this standard model. In this thesis, we report the detection of polarized anisotropy in the Cosmic Mi- crowave Background radiation with the Degree Angular Scale Interferometer (DASI), located at the Amundsen-Scott South Pole research station.
    [Show full text]
  • From Current Cmbology to Its Polarization and SZ Frontiers Circa TAW8 3
    AMiBA 2001: High-z Clusters, Missing Baryons, and CMB Polarization ASP Conference Series, Vol. 999, 2002 L-W Chen, C-P Ma, K-W Ng and U-L Pen, eds Concluding Remarks: From Current CMBology to its Polarization and Sunyaev-Zeldovich Frontiers circa TAW8 J. Richard Bond Canadian Institute for Theoretical Astrophysics, University of Toronto, Toronto, Ontario, M5S 3H8, Canada Abstract. I highlight the remarkable advances in the past few years in CMB research on total primary anisotropies, in determining the power spectrum, deriving cosmological parameters from it, and more generally lending credence to the basic inflation-based paradigm for cosmic struc- ture formation, with a flat geometry, substantial dark matter and dark energy, baryonic density in good accord with that from nucleosynthe- sis, and a nearly scale invariant initial fluctuation spectrum. Some pa- rameters are nearly degenerate with others and CMB polarization and many non-CMB probes are needed to determine them, even within the paradigm. Such probes and their tools were the theme of the TAW8 meeting: our grand future of CMB polarization, with AMiBA, ACBAR, B2K2, CBI, COMPASS, CUPMAP, DASI, MAP, MAXIPOL, PIQUE, Planck, POLAR, Polatron, QUEST, Sport/BaRSport, and of Sunyaev- Zeldovich experiments, also using an array of platforms and detectors, e.g., AMiBA, AMI (Ryle+), CBI, CARMA (OVROmm+BIMA), MINT, SZA, BOLOCAM+CSO, LMT, ACT. The SZ probe will be informed and augmented by new ambitious attacks on other cluster-system observables discussed at TAW8: X-ray, optical, weak lensing. Interpreting the mix is complicated by such issues as entropy injection, inhomogeneity, non- sphericity, non-equilibrium, and these effects must be sorted out for the cluster system to contribute to “high precision cosmology”, especially the quintessential physics of the dark energy that adds further mystery to a dark matter dominated Universe.
    [Show full text]
  • A Fast Iterative Multi-Grid Map-Making Algorithm for CMB Experiments
    A&A 374, 358–370 (2001) Astronomy DOI: 10.1051/0004-6361:20010692 & c ESO 2001 Astrophysics MAPCUMBA: A fast iterative multi-grid map-making algorithm for CMB experiments O. Dor´e1,R.Teyssier1,2,F.R.Bouchet1,D.Vibert1, and S. Prunet3 1 Institut d’Astrophysique de Paris, 98bis, Boulevard Arago, 75014 Paris, France 2 Service d’Astrophysique, DAPNIA, Centre d’Etudes´ de Saclay, 91191 Gif-sur-Yvette, France 3 CITA, McLennan Labs, 60 St George Street, Toronto, ON M5S 3H8, Canada Received 21 December 2000 / Accepted 2 May 2001 Abstract. The data analysis of current Cosmic Microwave Background (CMB) experiments like BOOMERanG or MAXIMA poses severe challenges which already stretch the limits of current (super-) computer capabilities, if brute force methods are used. In this paper we present a practical solution for the optimal map making problem which can be used directly for next generation CMB experiments like ARCHEOPS and TopHat, and can probably be extended relatively easily to the full PLANCK case. This solution is based on an iterative multi-grid Jacobi algorithm which is both fast and memory sparing. Indeed, if there are Ntod data points along the one dimensional timeline to analyse, the number of operations is of O(Ntod ln Ntod) and the memory requirement is O(Ntod). Timing and accuracy issues have been analysed on simulated ARCHEOPS and TopHat data, and we discuss as well the issue of the joint evaluation of the signal and noise statistical properties. Key words. methods: data analysis – cosmic microwave background 1. Introduction in this massive computing approach, i.e.
    [Show full text]
  • Mid-Infrared Selection of Brown Dwarfs and High-Redshift Quasars
    Submitted to the Astrophysical Journal Mid-Infrared Selection of Brown Dwarfs and High-Redshift Quasars Daniel Stern1, J. Davy Kirkpatrick2, Lori E. Allen3, Chao Bian4, Andrew Blain4, Kate Brand5, Mark Brodwin1, Michael J. I. Brown6, Richard Cool7, Vandana Desai4, Arjun Dey8, Peter Eisenhardt1, Anthony Gonzalez9, Buell T. Jannuzi8, Karin Menendez-Delmestre4, Howard A. Smith3, B. T. Soifer4,10, Glenn P. Tiede11 & E. Wright12 ABSTRACT We discuss color selection of rare objects in a wide-field, multiband survey span- ning from the optical to the mid-infrared. Simple color criteria simultaneously identify and distinguish two of the most sought after astrophysical sources: the coolest brown dwarfs and the most distant quasars. We present spectroscopically-confirmed examples of each class identified in the IRAC Shallow Survey of the Bo¨otes field of the NOAO Deep Wide-Field Survey. ISS J142950.9+333012 is a T4.5 brown dwarf at a distance of approximately 42 pc, and ISS J142738.5+331242 is a radio-loud quasar at redshift z = 6.12. Our selection criteria identify a total of four candidates over 8 square degrees of the Bo¨otes field. The other two candidates are both confirmed 5.5 <z< 6 quasars, previously reported by Cool et al. (2006). We discuss the implications of these dis- coveries and conclude that there are excellent prospects for extending such searches to cooler brown dwarfs and higher redshift quasars. 1Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., Mail Stop 169-506, Pasadena, CA 91109 [e-mail: [email protected]]
    [Show full text]
  • A Bit of History Satellites Balloons Ground-Based
    Experimental Landscape ● A Bit of History ● Satellites ● Balloons ● Ground-Based Ground-Based Experiments There have been many: ABS, ACBAR, ACME, ACT, AMI, AMiBA, APEX, ATCA, BEAST, BICEP[2|3]/Keck, BIMA, CAPMAP, CAT, CBI, CLASS, COBRA, COSMOSOMAS, DASI, MAT, MUSTANG, OVRO, Penzias & Wilson, etc., PIQUE, Polatron, Polarbear, Python, QUaD, QUBIC, QUIET, QUIJOTE, Saskatoon, SP94, SPT, SuZIE, SZA, Tenerife, VSA, White Dish & more! QUAD 2017-11-17 Ganga/Experimental Landscape 2/33 Balloons There have been a number: 19 GHz Survey, Archeops, ARGO, ARCADE, BOOMERanG, EBEX, FIRS, MAX, MAXIMA, MSAM, PIPER, QMAP, Spider, TopHat, & more! BOOMERANG 2017-11-17 Ganga/Experimental Landscape 3/33 Satellites There have been 4 (or 5?): Relikt, COBE, WMAP, Planck (+IRTS!) Planck 2017-11-17 Ganga/Experimental Landscape 4/33 Rockets & Airplanes For example, COBRA, Berkeley-Nagoya Excess, U2 Anisotropy Measurements & others... It’s difficult to get integration time on these platforms, so while they are still used in the infrared, they are no longer often used for the http://aether.lbl.gov/www/projects/U2/ CMB. 2017-11-17 Ganga/Experimental Landscape 5/33 (from R. Stompor) Radek Stompor http://litebird.jp/eng/ 2017-11-17 Ganga/Experimental Landscape 6/33 Other Satellite Possibilities ● US “CMB Probe” ● CORE-like – Studying two possibilities – Discussions ongoing ● Imager with India/ISRO & others ● Spectrophotometer – Could include imager – Inputs being prepared for AND low-angular- the Decadal Process resolution spectrophotometer? https://zzz.physics.umn.edu/ipsig/
    [Show full text]
  • Imagine the Universe News - 1 March 2001 3/7/01 6:40 PM
    Imagine the Universe News - 1 March 2001 3/7/01 6:40 PM ˚enter search text ____________________________________________________________________________________________ Imaginemagine the Universe News Thee Latest on the Structure and Evolution of Our Universe For More ____________________________________________________________________________________________ Information... Vol 5. No. 4 1 March 2001 Classyassy Antarctic Balloon Learn more Capturesr es the Earliest Light of about the Universe electromagnetic radiation. McMurdo Station,n, Antarctica -- If you think penguins in Antarctica look classy in their tuxedos, you shoulduld see our scientific balloon wearing a top hat. Read questions and answers about cosmology. Visit the TopHat, an innovativevative hat-shaped TopHat site! astronomy experimentriment that sits on top of a balloon, circled around the frozen continent Antarctic at 120,000 feet foror nearly two weeks in Experiments for Beginning January, collectingng light from the cosmic Scientists microwave backgroundgroundradiation . The flight was a success, and TopHat scientists are noww back in the relative warmth of the Unitednited States, beginning the News Archive yearlong processs of analyzing the data. Observing the microwaveicrowave background, formed about 300,0000,000 years after the big bang, enables scientistsientists to understand the nature of our Universeiverse when it was an infant. The radiationtion comes from an era before the creationon of stars andgalaxies . The Universe is now about 10 to 15 billion TopHat Launch years old. Click for larger image. "It is remarkable that we can determine so much with such data," said Stephan Meyer, a TopHat scientist at the University of Chicago. "For instance, we can measure the mass of the Universe to about 10 percent accuracy. The data will also help to establish whether the Universe will expand forever, or eventually collapse upon itself." TopHat measures the clumpiness of matter when the Universe was very young.
    [Show full text]
  • A Large Sky Simulation of the Gravitational Lensing of the Cosmic
    Draft version November 2, 2018 Preprint typeset using LATEX style emulateapj v. 08/22/09 A LARGE SKY SIMULATION OF THE GRAVITATIONAL LENSING OF THE COSMIC MICROWAVE BACKGROUND Sudeep Das & Paul Bode Princeton University Observatory Peyton Hall, Ivy Lane, Princeton, NJ 08544 USA Draft version November 2, 2018 ABSTRACT Large scale structure deflects cosmic microwave background (CMB) photons. Since large angular scales in the large scale structure contribute significantly to the gravitational lensing effect, a realistic simulation of CMB lensing requires a sufficiently large sky area. We describe simulations that include these effects, and present both effective and multiple plane ray-tracing versions of the algorithm, which employs spherical harmonic space and does not use the flat sky approximation. We simulate lensed CMB maps with an angular resolution of 0.′9. The angular power spectrum of the simulated sky agrees well with analytical predictions. Maps∼ generated in this manner are a useful tool for the analysis and interpretation of upcoming CMB experiments such as PLANCK and ACT. Subject headings: cosmic microwave background — gravitational lensing — large-scale structure of universe — methods: N-body simulations — methods: numerical 1. INTRODUCTION gular size produce small-scale distortions in the CMB, While the current generation of CMB experiments have thereby transferring power from large scales in the CMB had a significant impact on cosmology by helping to es- to the higher multipoles. Also, although the primordial tablish a standard paradigm for cosmology (Spergel et al. CMB can be safely assumed to be a Gaussian random 2003, 2007), the upcoming generation of CMB experi- field (Komatsu et al.
    [Show full text]
  • Development and Preliminary Results of Point Source Observations
    The Atacama Cosmology Telescope: Development and Preliminary Results of Point Source Observations Ryan P. Fisher A DISSERTATION PRESENTED TO THE FACULTY OF PRINCETON UNIVERSITY IN CANDIDACY FOR THE DEGREE OF DOCTOR OF PHILOSOPHY RECOMMENDED FOR ACCEPTANCE BY THE DEPARTMENT OF PHYSICS [Adviser: Joseph W. Fowler] November 2009 c Copyright by Ryan Patrick Fisher, 2009. All rights reserved. Abstract The Atacama Cosmology Telescope (ACT) is a six meter diameter telescope designed to measure the millimeter sky with arcminute angular resolution. The instrument is cur- rently conducting its third season of observations from Cerro Toco in the Chilean Andes. The primary science goal of the experiment is to expand our understanding of cosmology by mapping the temperature fluctuations of the Cosmic Microwave Background (CMB) at angular scales corresponding to multipoles up to ` ∼ 10000: The primary receiver for current ACT observations is the Millimeter Bolometer Ar- ray Camera (MBAC). The instrument is specially designed to observe simultaneously at 148 GHz, 218 GHz and 277 GHz. To accomplish this, the camera has three separate de- tector arrays, each containing approximately 1000 detectors. After discussing the ACT experiment in detail, a discussion of the development and testing of the cold readout elec- tronics for the MBAC is presented. Currently, the ACT collaboration is in the process of generating maps of the microwave sky using our first and second season observations. The analysis used to generate these maps requires careful data calibration to produce maps of the arcminute scale CMB tem- perature fluctuations. Tests and applications of several elements of the ACT calibrations are presented in the context of the second season observations.
    [Show full text]
  • Cosmic Microwave Background Theory
    Proc. Natl. Acad. Sci. USA Vol. 95, pp. 35–41, January 1998 Colloquium Paper This paper was presented at a colloquium entitled ‘‘The Age of the Universe, Dark Matter, and Structure Formation,’’ organized by David N. Schramm, held March 21–23, 1997, sponsored by the National Academy of Sciences at the Beckman Center in Irvine, CA. Cosmic microwave background theory J. RICHARD BOND* Canadian Institute for Advanced Research Cosmology Program, Canadian Institute for Theoretical Astrophysics, 60 Saint George Street, Toronto, ON M5S 3H8, Canada ABSTRACT A long-standing goal of theorists has been to ponent in gravitational wave tensor perturbations; the power 3 3 3 constrain cosmological parameters that define the structure spectra for these modes, F(k), is(k), GW(k) as a function formation theory from cosmic microwave background (CMB) of comoving wavenumber k. Sample initial and evolved power 2 anisotropy experiments and large-scale structure (LSS) ob- spectra for the gravitational potential 3F(k)([ dsFydln k, servations. The status and future promise of this enterprise is the rms power in each dln k band) are shown in Fig. 1. As the described. Current band-powers in ø-space are consistent with Universe evolves the initial shape of 3F is modified by a DT flat in frequency and broadly follow inflation-based characteristic scales imprinted on it that reflect the values of expectations. That the levels are ;(1025)2 provides strong cosmological parameters such as the energy densities of bary- support for the gravitational instability theory, while the Far ons, cold and hot dark matter, in the vacuum (cosmological Infrared Absolute Spectrophotometer (FIRAS) constraints on constant), and in curvature.
    [Show full text]
  • The History of Astrophysics in Antarctica
    The History of Astrophysics in Antarctica B. T. IndermuehleA,C, M. G. BurtonB, and S. T. MaddisonA A Centre for Astrophysics and Supercomputing, Swinburne University, VIC 3122, Australia B School of Physics, University of New South Wales, Sydney, NSW 2052, Australia C E-mail: [email protected] Abstract We examine the historical development of astrophysical science in Antarctica from the early 20th century until today. We find three temporally overlapping eras, each having a rather distinct beginning. These are the astrogeological era of meteorite discovery, the high energy era of particle detectors, and the photon astronomy era of microwave, sub–mm and infrared telescopes, sidelined by a few niche experiments at optical wavelengths. The favourable atmospheric and geophysical conditions are briefly examined, followed by an account of the major experiments and a summary of their results. Keywords: history and philosophy of astronomy – site testing – cosmic microwave back- ground – infrared: general – sub–millimetre – cosmic rays 1 Prehistory The first written account of astronomical observations south of the Antarctic Circle dates back to 1772 (Bayly & Cook 1782), when the appointed astronomer and navy officer William Bayly made astrometric measurements aboard the ships “Discovery” and “Resolution”. On their voyage, led by Captain James Cook, they circumnavigated Antarctica, crossing the Antarctic Circle three times from 1772 to 1775. The main objective of the observations was to establish positional accuracy in order to create charts of their discoveries. For that purpose they were equipped with several different compass designs, an astronomical quadrant and a Hadley sextant, as well as accurate chronometers built on the principles of Harrison’s ship chronometer (Andrewes 1996).
    [Show full text]
  • Images of the Early Universe from the Boomerang Experiment
    Image Earle th f yso Universe from the BOOMERanG experiment Bernardise Pd . 1, P.A.R.Ade2, JJ.Bock3, J.R.Bond4, J.Borrill5'6, A.Boscaleri7, K.Coble8, B.P.Crill9, G.De Gasperis10, G.De Troia1, P.C.Farese8, P.G.Ferreira11, K.Ganga9'12, M.Giacometti1, E.Hivon9, V.V.Hristov9, AJacoangeli1, A.HJaffe6, A.E.Lange9, L.Martinis13, S.Masi1, P.Mason9, P.D.Mauskopf14'15, A.Melchiorri1, L.Miglio16, T.Montroy8, C.B.Netterfield16, E.Pascale7, F.Piacentini1, G.Polenta1, D.Pogosyan4, S.Prunet4, S.Rao17, G.Romeo17, J.E.Ruhl8, F.Scaramuzzi13, D.Sforna1, N.Vittorio10 Dipartimento1 Fisica,di Universitd Romadi Sapienza,La 001852, P.leRoma,Mow A. Italy, 2 Department of Physics, Queen Mary and Westfield College, Mile End Road, London, El 4NS, UK, 3 Jet Propulsion Laboratory, Pasadena, CA, USA, 4 CITA University of Toronto, Canada, NERSC-LBNL,5 Berkeley, USA,CA, 6 Center for Particle Astrophysics, University of California at Berkeley, 301 Le Conte Hall, Berkeley CA 94720, USA, 1IROE CNR,- PanciatichiVia 64,50127 Firenze, Italy, 8 Department of Physics, University of California at Santa Barbara, Santa Barbara, CA 93106, USA, 9 California Institute of Technology, Mail Code: 59-33, Pasadena, CA 91125, USA, 10 Dipartimento di Fisica, Universitd di Roma Tor Vergata, Via della Ricerca Scientifica 1, 00133 Roma, Italy, 1 ] Astrophysics, University of Oxford, Keble Road, 3RH,OX1 UK, 12 PCC, College de France, 11 pi. Marcelin Berthelot, 75231 Paris Cedex 05, France, 13 ENEA Centra Ricerche Frascati,i d . FermiE a , 00044Vi 45 Frascati, Italy, 4 Physics1 Astronomyd an Dept, Cardiff University,, UK 5 Dept1 of Physics Astronomy,d an UMass.
    [Show full text]
  • Jeff Filippini
    The View from the Stratosphere Systematics and Calibration Challenges of CMB Ballooning Jeff Filippini CMB Systematics / Calibration Workshop 01Dec2020 Why Ballooning? The Good • High sensitivity to approach CMB photon noise limit • Access to higher frequencies obscured from the ground • Retain larger angular scales due to reduced atmospheric fluctuations (less aggressive filtering) • Technology pathfinder for orbital missions 101 100 The Bad -1 10 • Limited integration time (~weeks) 10-2 • Stringent mass, power constraints 10-3 • Very limited bandwidth demands 10-4 nearly autonomous operations Sky Radiance [pW/GHz] -5 10 1 km 10 km 30 km 101 102 103 A.S. Rahlin / am model Frequency [GHz] Excellent proxy for space operations! A Rich History BOOMERanG 1998 ARCADE 2 2006 SPIDER 2015 MAXIMA 1999 EBEX 2012 OLIMPO 2018 … plus BAM, QMAP, Archeops, TopHat, PIPER, and many more! Balloonatics The SPIDER Program A balloon-borne payload to identify primordial B-modes on degree angular scales in the presence of foregrounds Large (~1300L) shared LHe cryostat Modular: 6 monochromatic refractors • SPIDER 2015: 3x95 GHz, 3x150 GHz • SPIDER-2: 2x95, 1x150, 3x280 GHz Stepped half-wave plates (HWPs) Lightweight carbon fiber gondola Azimuthal reaction wheel, linear elevation drive Launch mass: ~6500 lbs (3000 kg) Nagy+ ApJ 844, 151 (2017) O’Dea+ ApJ 738, 63 (2011) Rahlin+ Proc. SPIE (2014) Filippini+ Proc. SPIE (2010) Fraisse+ JCAP 04 (2013) 047 … and more … SPIDER Receivers • Monochromatic 2-lens refractors Cold HDPE lenses, 264mm stop • Emphasis on low internal loading • Predominantly reflective filter stack Metal-mesh + one 4K nylon • Inter-lens 1.6K absorptive baffling • Thin vacuum window (3/32” UHMWPE) • Reflective wide-angle fore baffle • Polarization modulation with stepped cryogenic HWP (AR-coated sapphire) • Antenna-coupled TES arrays SPIDER-2: Horn-coupled TES arrays Challenges of CMB Ballooning Ballooning shares all of the same systematics and calibration challenges as anyone else - see e.g.
    [Show full text]