8/3/2019 B.T. Indermuehle, M.G. Burton and S.T. Maddison- The History of Astrophysics in Antarctica

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The History of Astrophysics in AntarcticaB.T. Indermuehle1, M.G. Burton2, S.T. Maddison1

(1) Centre for Astrophysics and Supercomputing, Swinburne University (2) University of New South Wales

AstrogeologicalEra

starts1912

HighEnergyErastartsmid19

50s

Abstract

We examine the historical development of astrophysical science at the bottom of the world from the early 20th century until today. We find three temporally overlapping eras with each having a rather distinct beginning. Thesere the photon astronomy era of microwave, sub-mm and infrared telescopes, sidelined by a few optical niche experiments, the high energy era of particle detectors and the astrogeological era of meteorite discovery. Theavourable atmospheric and geophysical conditions are briefly examined followed by an account of the major experiments and a summary of their results. A scientific effectiveness analysis of the various projects is presenteduantitatively.

1912 Mawson finds the first meteorite in Adelie Land. Its a stony meteorite (OC/L5) measuring roughly 13 x 9 x 6 cm. Thiswas a complete chance find by F.H. Bickerton, one of Mawsons sledging party leaders on discovery tour in awestern direction from Cape Denison.11

1961 Russian geologists discover several meteorites of different kinds in the Lazarev region. 12

1969 A Japanese group of geologists undertakes the first formal meteorite search program based on geological andglaciological theories which explain why such a heterogenous accumulation of meteorites are found on one place andin such great quantities (see Fig. 1). They successfully retrieved many different kinds of meteorites (enstatitechondrites, hypersthene achondrites, type III carbonaceous chondrites and bronzite chondrite).

rences:n et al. The Scientific Potential for Astronomy from the Antarctic Plateau, PASA 1994 11/(2) 127-50

G., Fossat, E. & Pomerantz, M., 1980. Solar oscillations: full disk observations from the geographic South Pole.

e, 288, 541 - 544 J.P, His personal Website, http://www.astro.ufl.edu/%7Eoliver/#top

ni, M.; Recabarren, P.; Ferreiro, D.; Renzi, V.; Ozu, R. Reporte de actividades de la Estacin Astronmica Polar `J.L.Sersic,n de la Asociacin Argentina de Astronoma, vol.42, p.67-69

es of the NSF, http://www4.nas.edu/arc.nsf/web/igyhistory?OpenDocumentsity of California Berkeley, 2002, http://amanda.berkeley.edu/amanda/amanda.html

dig et al. ANARE Research Notes 102, pp. 57 60, 2000

Research Foundation, South Pole Air Shower Experiment, 2002, http://www.bartol.udel.edu/spase/ro, E. G.; Storini, M.Cosmic-ray measurements inAntarctica during the international Solar-Terrestrial Energy Program,

Cimento C, Serie 1 (ISSN 0390-5551), vol. 15 C, no. 5, p. 539-545, 10/1992te communication with Dr. Christian Spierig of DESY, Fall 2002 [csspier@ifh.de]

W. Bayly, F.L. Stillwell, The Adelie Land Meteorite, Scientific Reports Series A, Vol. IV, Geology, A.J. Kent, Sydney 1923lete Listing of Antarctic Meteorites in the U.S. Collection, http://curator.jsc.nasa.gov/curator/antmet/us_clctn.htm

Background: NGC6334 PAHs in IR by Burton et al. / SPIREX

Fig. 5 (image courtesy NASA/JPL)

today, thousands of meteorites have been retrieved from Antarctica. It remains one of the most important sources on earth for the dryness and cold lessens erosive

s on the meteorites and the mechanisms explained in Fig. 5 contribute in accumulating them in one place for easy collection.

PhotonAstronomyEra

startslate1970s

52, the first Antarctic astrophysical project was started when the International Council of Scientific Unions (ICSU) proposed to execute a comprehensive series of global geophysical activities to span the period from Julyto December 1958. This was to be called The International Geophysical Year (IGY)5, and it was modelled after the International Polar Years of 1882-1883 and 1932-1933. The intention was to allow scientists from all over

world to take part in a series of coordinated observations of various geophysical phenomena. The United States among other projects supported a cosmic ray detector which was to be located at McMurdo station. A secondctor was built at the South Pole in 1964 and many others were commissioned at most of the various national research stations in Antarctica. Today, cosmic rays with energies above 50 TeV are being captured bySE4, the large area air shower array established at the geographic South Pole. At these energies, the flux of events is too low to measure on considerably smaller short duration balloon flight experiments or morensive satellite missions. The array is situated in the dark sector (a region where anthropogenic interference is minimal) near the Amundsen-Scott South Pole Station and just on top of where the Antarctic Muon And

rino Detector Array (AMANDA)6 is located today.

1955 Muon Detector installed at Mawson7

1961 Cosmic Ray detector installed at McMurdo1964 Second Cosmic Ray detector operates at South Pole1987 SPASE-1 (South Pole Air Shower Experiment) operated for 10 years (until SPASE-2) and consisted of 16 1m2 scintillator detectors at 14 locations on a 30 meter triangular

grid. The primary purpose was to search for point sources of ~100 TeV gamma radiation.8

1991 AMANDA (Antarctic Muon And Neutrino Detector Array) consists of widely spaced photomultiplier tubes (PMTs) which are placed into holes in the South Polar icecap ranging from several hundred meters in depth to 3 km. High energy neutrinos coming up through the earth will occasionallyinteract with ice or rock and create amuon which in turn emits Cherenkov light when passing through the ice which is detected by the PMTs.

1992 Chile executes cosmic ray measurements at Marsh Base on King George Island9

1995 RICE (Radio Ice Cherenkov Experiment) detects ultra high energy electron neutrinos through their interactions with ice molecules in the Antarctic icecap based on theprinciple of radio coherence. The Experiment has determined upper EeV neutrino flux limits. 10

1997 SPASE-2 consists of 120 scintillator modules spread over an area of 16000m 2 working in coincidence with AMANDA.2003 AMANDA II will contain roughly a third more PMTs and will operate 90% of the time with at least 600 PMTs operative, thus makingit the worlds most active neutrino

detector.2006 IceCube will be a 1 km3 array opening up the PeV energy region where the Universe is opaque to high energy gamma rays originating from the edge of our galaxy.

on astronomy is further subdivided into several regions of atmospheric windows for our purpose of astrophyiscal experiments in Antarctica: Microwave, sub-millimetre, infrared and optical. Of those, opticalnomy has mainly been employed for site testing and evaluation. During the winter over operations in 1964 for the cosmic ray observatory at South Pole, a semi-quantitative analysis of the stellar and solar observationitions was made with a small 3.5" aperture telescope and the results were very promising. The advantages of Antarctica for astronomy at infrared wavelengths stem directly from its dark skies, cold temperatures,e atmosphere, and the ability to observe objects continuously throughout the long winter night. The sky at the South Pole in the thermal infrared is darker than in any other ground based site, by as much as two ordersagnitude and thus dramatically reducing photon noise and minimizing the effects of changes in sky brightness. Atmospheric homogeneity further reduces the variability of the sky emission above the polar plateau. Theg temperature inversion at the South Pole helps cooling the telescopes to a colder temperature than the mean atmospheric temperature. The limit set by the atmospheric emission can thus easily be reached and

ument noise is minimal. In the High-Energy spectrum, the earth magnetic field normally shields or at least deflects a significant amount of the heavier particles travelling through space. At the poles, the magnetic fieldalmost vertically enter the surface of the earth, thus creating a port of entry for charged particles. The other advantage is found in the vast amount of ice available to create a natural Cherenkov radiation detector.

1964 Seeing evaluation at South Pole with an optical telescope.1979 First scientific project: Fossat, Grec and Pomerantz coupled a sodium vapour cell to a small telescope and obtained an unbroken run of

over 120 hours of solar observations measuring solar oscillations. The data they returned allowed hundreds of solar eigenmodes to bediscovered.2

1984 SPOT (South Pole Optical Telescope) Measurements were taken during austral summer and evaluated the seeing conditions in thevisible region of the electromagnetic spectrum3.

1988 Italian CMB (Cosmic Microwave Background) experiment in Terra Nova Bay at an angular scale of 1.3.1991 White Dish, the first in a series of CMBR experiments, starts at South Pole.1992 Python was a 0.75 class meter telescope producing CMBR Maps (See Fig. 3)1993 SPIREX (South Pole Infrared Explorer) mainly produced images of PAHs with the Grim and Abu imagers until its decomission in 1999.1994 Argentinian researchers evaluate the UBVRI skies from the General Belgrano station using a C11 telescope and found only 3.8 arcsec

skies, completely unsuitable for any kind of astronomy in the UV to IR bands.4

1997 Viper replaced Python with a 2.1 meter off-axis telescope optimised for CMB observations.1997 AASTO (Automated Astrophysical Site Testing Observatory) was comissioned to evaluate the atmospheric window from UV to sub-

mm. The AASTO package consists of a suite of instruments such as the Near-Infrared Sky Monitor (NISM), the Mid-Infrared Sky Monitor(MISM) (both instruments are used to monitor sky brightness in the respective wavelengths), the Antarctic Fibre-Optic Spectrometer(AFOS) which is used to measure atmospheric transmission in the UV to about 800 nm, a Sonic Radar (SODAR) used to measure theheight of the turbulent atmospheric boundary layer and the Sub-millimetre Tipper (SUMMIT) used to monitor 350 micron radiation.

1998 DASI (Degree Angular Scale Interferometer) specifically complemented Viper in its sub-mm and mm capabilities.1998 Boomerang (Flight 1) provided a much improved CMB map. (See Fig. 4)2000 ACBAR (Arc minute Cosmology Bolometer Array Receiver) was a 16 element 300 mK bolometer array designed specifically for

observations of CMB anisotropy and the Sunyaev-Zeldovich Effect (SZE) and was mounted on the Viper platform.

Fig.4 Boomerang CMB Map

Fig. 3 Python CMBR Map

Quantitative display of publications basedon science results of antarctic telescopesIn the process of collecting information on thevarious observatories, the amount of publishedpapers has been compared to the number ofyears a given observatory or instrumentremained in service and the divisor of these twofigures resulted in a Papers per Year or PpYnumber that may help determining the scientificimpact any given instrument had. Fig. 6illustrates this for all of the instruments portrayedhere.

ity of the atmospheric window

AtmosphericWindow Comparison

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1 3 7 13 28 49 94 164 234 466 746 1131 2 531 5 792 6 288

Wavelength[nm]

Transmission

Antarctica

Mauna Kea

Siding Spring

esting instruments have measured the 1.25 - 14 micron sky brightness and recorded the incidence of clear skies suitable for astronomicalvations. About 50% of all nights are found to be of good quality. Precipitable water vapour is very low and atmospheric models and testingconfirmed the conditions to be ideal1. In the near and mid infrared, the best window is located between 2.3 and 2.45 microns. Residual

sion in this window is thought to be coming from airglow at altitudes above 38 km and interestingly, no correlation is observed between mided sky brightness and auroral activity. At longer wavelengths (in the L and M bands), advantages are even greater since at warmer sitesghout the world the infrared arrays rapidly saturate due to the high thermal backgrounds. Background brightness is higher at other sites byst a factor of 50. In the N band from 8 - 13 microns, the sky brightness is between a third and a tenth t hat of other sites. At wavelengthser than 2.3 microns, the gains are fairly modest because the sky brightness is dominated by OH airglow rather than thermal emission.ow is still half as bright as in lesser suitable locations. Since the quality of the observing conditions at wavelengths longer than 3 micronsnds principally on temperature, good observing conditions extend well beyond the boundaries of the polar night. Fig. 1: Precipitable Water Vapour Fig. 2: Atmospheric window

Fig. 6: Quantitative Analysis Papers per Year

From: Improved Measurement of the Angular Power Spectrumof Temperature Anisotropy in the CMB from Two New Analysesof BOOMERANG Observations, Ruhl et al. Dec 2002

From: http://cmbr.phys.cmu.edu/pyth.html

From: http://astro.uchicago.edu/cara/research/site_testing/submm.html Data from1

ScienceStatist

ics

1989-2002