Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.naic.edu/~astro/School/Talks/brown_future.pdf Дата изменения: Tue Jul 12 03:58:00 2005 Дата индексирования: Sat Dec 22 10:43:57 2007 Кодировка: Поисковые слова: universe

The Future of Single Dish Radio Astronomy
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"FUTURE"
Year 2001 Vision*
Determine the large-scale properties of the universe: its age, the nature (amount and distribution) of matter and energy that make it up, and the history of its expansion. Study the dawn of the modern universe, when the first stars and galaxies formed. Understand the formation and evolution of black holes of all sizes. Study the formation of stars and their planetary systems, and the birth and evolution of giant and terrestrial planets Understand the effects of the astronomical environment on Earth.
Physics and Astronom y, U.S. National Research Council ("T aylor-McKee Report"), 2001.

Robert L. Brow n NAIC

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*A stronom y and A strophysics in the New Millennium , Astronom y and Astrophysics Survey Comm ittee, Board on

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Robert L. Brown

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"Future"
Year 2003 Vision*
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"Future"
Year 2003 Vision*
Are proto ns uns table? What are the new states of matter at exceedingly high density and temperature? 9. Are there additio nal space-tim e dim ensio ns? 10. How wer e the elem ents from Iron to uranium made? 11. Is a new theo ry of matter and li ght need ed at the highest energies?
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*Connecting Q uarks with the Cosmos, Eleven Science Questions for the New Century, Com mittee on the Physics of the U niverse, National Research Council, ("T urner Report"), 2003.

What is Dark Matter? What is the nature of Dark Energy? How did the universe begin? Did Einstein have the last wo rd on Gravity? What are the mass es of neutrinos , and how have they shaped the evolutio n of the univers e? How do cosmic accelerators work and what are they accelerating?
2005 NAIC/ NRAO As tronomy Single Dis h Summer Sc hool 3

*Connecting Q uarks with the Cosmos, Eleven Science Questions for the New Century, Com mittee on the Physics of the U niverse, National Research Council, ("T urner Report"), 2003.
Robert L. Brown

Robert L. Brown

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"Single Dish"
One p hysica lly-contiguous, light-ga thering, structure.
May have response (light-gathering po wer) in more than one directio n May have beam-form ing network at the focal point (i.e. can form a teles cope beam electro nically no t optically) .


"Radio Astronomy"
The study o f celestial objec ts at w aveleng ths fro m the ground-ba sed iono spheric cutoff ( ~10 M Hz) to the ground-ba sed atmosp heric cuto ff (~1000 GHz) .
Definitio n is a practical one, no t a phys ical one Excellent gro und-based sites count for the definitio n This is a facto r of ~105 in w avelength--o ne sho uld expect a change in telescope technology across this w avelength span.
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Robert L. Brown













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A Science- Driv en Future of Singl e Dish Radi o Astronomy
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A Science- Driv en Future of Singl e Dish Radi o Astronomy
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EOR Map HI sky brightness as a function of source turn-on time ( reds hift) : 50(?) ­ 200(?) MHz Star/planet Formation Characteriz atio n of star/ planet formatio n enviro nm ent (chemistry, excitation, magnetic field) Solar Sys tem-Earth eff ects Chemis try of comets, planetary atmospheres, radar characterizatio n of NEAs
2005 NAIC/ NRAO As tronomy Single Dis h Summer Sc hool 7

Dark Matter Dynamics of galaxies and gro ups of galaxies (large-s cale HI and CO surveys) Origin of the Universe Gravity waves ( precisio n puls ar timing) Gravity, theory of Large s cale: kinem atics of galaxies and clus ters of galaxies Small scale: Precision timing of binary puls ar s ystems
2005 NAIC/ NRAO As tronomy Single Dis h Summer Sc hool 8

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Robert L. Brown

Robert L. Brown

A Science- Driv en Future of Singl e Dish Radi o Astronomy
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New States of Matter Precision puls ar timing--m aximum spin rate related to the equation of state of a neutro n star ("quark s tar"?) New Theories of Matter and Light Extreme environment: pulsar emissio n mechanisms
2005 NAIC/ NRAO As tronomy Single Dis h Summer Sc hool 9

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Robert L. Brown

Robert L. Brown

Technology f or Futur e of Sing le Dish Radi o Astronomy
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Fixed antenna designs of large aperture
Maxi mize s c ol lecting ar ea for gi ven c ost at the e xpen se of sky c ove rage

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Robert L. Brown



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"Commensual" observing Wideband IF signal processing for multiple, simultaneous scientific users with different science objectives Made possible now by lo w cost digital hardware and processing



Multibeaming with Array Detectors to increase the instantaneous field of vie w Made possible now by lo w cost HFET and MMIC receivers

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Masses of neutrinos Spatial distributio n of matter as a function of redshift for comparison with models

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Req uirements f or the F utur e of Sing le Dish Radio Astronomy
Survey Capability--Large Field of View EOR HI , C O Pulsars "Dis covery Space" Dedicated Access Flexibility Spectral co verage, multiple sim ultaneous us ers , RFI mitigatio n techniques
2005 NAIC/ NRAO As tronomy Single Dis h Summer Sc hool 10

(Near) Future Single Dish Radio Telescopes
LMT CO spectrosco py of high reds hift galaxies FAST HI Spectros copy Pulsar tim ing APEX, CCAT CO spectrosco py of high reds hift galaxies Spatial distributio n of ULIRG as a function of redshif t
2005 NAIC/ NRAO As tronomy Single Dis h Summer Sc hool 12

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(Longer Term) Future of Single Dish Radio Astronomy [Speculation]
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Telescopes designed a nd built for a specific scientific objec tive Emp hasis on larg e-as-possible insta nta neous field o f view-- hea vy emp hasis o n multib ea ming Scientific pa rtnerships in telescope desig n a nd construction ( international, institutio nal) are the rule, not the exceptio n
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Robert L. Brown

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