History of the Radio Astronomy in Toruń

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History of the Radio Astronomy in Toruń
Radio Astronomy
the Challenge for
Science and Technology
Andrzej Kus, Torun Centre for Astronomy, NCU
YERAC Torun 9.09.2014
Torun Centre for Astronomy UMK
Piwnice near Toruń
http://www.astri.uni.torun.pl
TRAO
Optical Observatory
Karl Jansky
(1901-1984)
Grote Reber (1905-2007 )
Sir Martin Ryle dr.h.c. UMK
Sir Anthony Hewish
Mullard Radio Astronomy Observatory, Cambridge University, England
Torun’s Radio Astronomy had a very good contacts with MRAO via the British Council
Prof. Dr. Władysław Dziewulski
astronomer
Rector of the Vilnius Stefan Batory University
in 1936-1939
(second oldest University in Poland)
One of the founders of the
Niclolaus Copernicus University
in Torun 1945
Vice Rector of the NCU
Director of Astronomical Observatory NCU
1945-1952
(1878 1962)
Prof. Wilhelmina Iwanowska
(1905 – 1999)
Founder of modern astrophysics in Torun
Director of Astronomical Observatory 1952-1977
Prof. Stanisław Gorgolewski
(1926 -2011)
Founder of Radio Astronomy in Torun
Director of TRAO 1974-1990
Radio Astronomy
Angular resolution ~1/D
• spectrum
• limitations
Sensitivity ~D
2
A radio astronomy system
Big dishes
and the medium size
(l /D)
10 x / 7 years
WSRT
VLA
Very Large Array
NRAO, Socorro,
USA
Nobeyama Observatory, Japan
solar interferometer
a single dish
Angular
resolution
q ~1/D
D
aperture synthesis
Very Long Baseline
Interferometry
EVN
VLBA
EVN
e-EVN
China
USA
South Africa
European VLBI Network
- Poland from 1982 (32m RT4 1996)
studies of AGNs & Masers
- e-EVN from 2004
VLBI Space Orbiting Programme
TRAO had participated in VSOP
8m
space
antenna
+ ground telescopes
And now TCfA is acive
in new space VLBI project
the Radio Astron
(receivers + collecting surface area)
~ D2
10 x / 7 years
 -ray
X-ray
Visible light
IR
HI
Radio
Planck Mission Satellite - all sky map2010, The Galaxy and the CMB
The Universe is transparent to radio waves
Cyg A
Vir A, M87
Tau A
3C273
M82
M42
Cen A
Our Galaxy
M31
Sgr A
NVSS
Cas A
3C84
Hyd A
Radio
Cas A
X-ray
Robert Duncan,
ATNF, Australia
Pulsars - magnetized neutron stars
MPIfR
data
X-ray image of
Crab pulsar envelope
Millisecond pulsars are
the most precise
astronomical clocks
47 Tucanae
Classical Radio Galaxy
gorąca plama
~100 kpc
lobe
Core
jet
Counter jet
lobe
Hot spot
Parent galaxy
gorąca plama
dżet
kontra dżet
jądro
M87 - 3C274
M87 radio jet – VLBI image
model
Neutral
Hydrogen
M81 & M82
M82
M81
HI distribution
simulation
for z = 2
Robert Braun
NFRA
MERLIN
T.Muxlow et al.
M82
<- VLBI Pedlar et al.
SN 1993j, Michael Rupen et al.
Gravitational
lensing
Optical image
1938+666
Einstein ring
Radio image from MERLIN
Winkilson and Browne of Jodrell Bank
2.7 K CMB
Big Bang !!!
and formation of galaxies
“Normal Matter”
4%
Dark Energy
73%
Dark Matter
23%
30m teleskop IRAM
Sgr B2-N
“Large Molecule Heimat”
In the band of 3 mm (70 – 116 GHz) within 500 MHz there
are 2000 – 3000 lines !!!!
10 minutes integratiion/spectrum  confusion limit
(Belloche, Comito, Hieret, Leurini, Menten, Schilke)
ALMA the new way to observe molecular clouds, protoplanets,
chemical evolution of the Universe, origin of life
The main Cosmic Masers
OH
H2O
SiO
CH3OH
example spectra of Torun methanol survey of galactic plane
3D tomography of
stellar atmospheres
stellar disk
Images made by Chapman (ATNF) at Jodrell Bank
with MERLIN telescopes
OH
H2O
Evolution of SiO masers in TX Cam
Diamond and Kambal
SiO
UK
SWE
D
SA
PL
G23.657 methanol maser
Anna Bartkiewicz et al.
It has a rich history of
discovery
• Over the past 50yr
– Pulsars
– Microwave Background
– Cosmic Evolution
– Dark Matter in galaxies
– Quasars
– Jets + Superluminal
motion
– Gravitational Radiation
– Aperture Synthesis
– First exoplanets (AW)
The Discovery of Pulsars
The Nobel Prizes
•
•
•
•
•
•
•
•
1974 M.Ryle, A.Hewish
1978 A.Penzias, R.Wilson
1983 S.Chandrasekhar, W.Fowler
1993 R.Hulse, J.Taylor
2002 R.Giacconi
2006 J.Mather, G.Smoot
2011 S.Perlmutter, B.Schmidt, A.Riess
2014/2015 (?)
Radio Astronomy (8)
Astrophysics, X-ray (6)
Technology Advances
• Antenna techniques
• Ultra low noise receivers
• Radiometry
• Remote sensing
• Interferometry IVS (geodesy)
• Navigation (Earth and Space)
• GPS
• Satellite TV brodcast
• Data processing methods
Practcal applications of radio astronomy technique
VLA
ESA
USA
SMOS
Cyg A
VLA
USA
Practical applications of radio astronomy techniques
Microwave cameras, skanners, radiometry,
Telecommunication, TV-sat, GPS, Space Navigation
OCRA-f multi beam system the cryostat
OCRA-f
front-end-module
MMIC hybrid
MMIC LNA
PHased Arrays for Reflector Observing Systems
PHAROS (FARADAY)
VI PR EU
Practical use of interferometry – the holography of 32m TRAO antenna
Surface errors [mm]
Point source PSF
Significant progress in modern astronomy is being made by
dramatic improvements of instrumental performance
- sensitivity, - angular resolution, - spectral resolution,
- time resolution these are of fundamental merit.
In observational astrophysics we still need :
- large apertures (but then small field of view, can only study
individual objects)
- telescopes for surveys with large field of view (statistical s.)
- telescopes in new spectral domains, + gravitational waves,
cosmic rays and more (?)
in RADIO progress possible if we get :
– higher sensitivity -> SKA
– higher angular resolution - VLBI (interferometry)
- new radio bands (mm - submm) -> ALMA
- new astronomical targets (yet unknown !)
But .... rising level of radio / light pollution !!!
Beginnings of Radio Astronomy in Poland
Cracow Observatory Torun Observatory
- 1954 first observations
of solar radio emission
O.Czyżewski,
A.Strzałkowski
J.Demezer,
Kozieł, Masłowski
5m antenna at l 90 cm
- 1970 15m antenna
- Solar Radio Emission
• Extragalactic
polarization studies
2015 LOFAR
-1958 first successful solar
observations, 12m antenna
S.Gorgolewski,
A.Manczalski,
J.Groszkowski,
- 1977 15m antenna
- 1994 32m antenna
VLBI, pulsars,
spectroscopy,
polarimetry
2018 ~90m antenna
Some historic photos from Torun Radio Astronomy Observatory
RT-1 30x12m
and its crew
58
RT-2 12m radio telescope, 1958
59
1972
43 MHz aperure synthesis telescope, the movable antenna , receivers rack , and data processing set-up
RT3 - the 15m radio telescope
commisioned in 1976
609 and 5000 MHz receivers
(high frequency electronics
received from Astron)
Receivers for 408 MHz and
10.7 GHz (with MPIf paramp)
VLBI tests in 1981/82
RT3 control room in 1986
new radio telescope 32m
in operation since 1996
Basic information on RT4
- Designed and built in Poland
- Homology design – „self correcting”
- Completed in ’94, operation since ’96
- Diameter 32m
- Cassegrain with 3.2m secondary
- Surface accuracy 0.4 mm RMS
- Pointing and tracking ~10 arcsec
- Total weight 600 Mg
- Motors in Az and El up to 30 deg/min
- Control fully computerized
- Radio receivers cover
750-1100 MHz
1400-1800 MHz
4400-5100 MHz
6100-7000 MHz
20000-24000 MHz
26000-34000 MHz
(30cm)
(20cm)
(6cm)
(5cm)
(1,35cm)
(1cm)
- VLBI terminal (MkIV => MkVa)
- Pulsar machine
- Autocorrelation spectrometer
- Polarymeter
- Hydrogen maser frequency standard
- OCRA – multi beam system
Current projects on RT4
•EVN
•Pulsars
•Radio spectroscopy
•Polarymetry
•OCRA – radio camera
• education
Radio polarimetry – a method of
measuring cosmic magnetic fields
Ψ ~ λ2 ne B‫װ‬
Radio waves emerge polarized
from magnetic field regions
Radio waves suffer rotation
In the interstellar medium
The measurement of polarization gives us 3D
information about the cosmic magnetic fields
Examples of maps from Torun polarization survey at 5 GHz
Cracow Astronomical Observatory
Jagiellonian University
15m RT
8m RT
+ LOFAR
+ CTA
Effelsberg
3,3 tys. ton, 100 MEuro
GBT 9 tys. ton, ~250 M$
RT4, weight 600 ton
cost ~8 MEuro
Large radio telescopes and their cost
Sardinia Radio Telescope (2012)
New large radio telescopes
~30 MEuro
60 MEuro
64 m SRT
Yebes Spain 40m
frequency cover up to 100 GHz
Miyun
50m
SHAO
Urumqi, Shanghai, NAOC
China Radio Telescopes
50m
65m
80,
120m
Urumqi 80+m
Five hundred meter Aperture Spherical Telescope
FAST in China (2015)
• 2x Arecibo
• 5x larger field-of-view
than Arecibo
500 m diameter
300 m active surface
+/- 30o sky coverage
130 MHz – 2(8.8) GHz
4” pointing
4x FAST => SKA
Cost ~100 M $
Da Wo Dang
Phased array concept
Basic idea: replace mechanical pointing & beam forming
by electronic means
VLA/e-VLA
Very Large Array
NRAO, Socorro,
USA
2012
Built in 1972-1980
78 millions $ (1975)
ALMA - Atacama Large Millimeter Array
International project (ESO, USA, Japan)
~50 antennae, each ~ 12m diameter
Configuration 0.15-10 km
Wave length 10-0.35 mm
Sensitivity 15 microJy – 100 mJy
Angular resolution 10 milli arcsec
Operation from 2012
Cost ~> 1 G Euro !
The Square Kilometre Array (2025)
Up to 1500 dishes each of 15m diameter, in central 5km
core plus another 1500 in groups at distance of 5 km to
3000+ km
+ aperture arrays – initially for all-sky monitor
connected to a massive data processor by an optical fibre
network
-Partners: USA, Europe, Australia, China
-Cost ~3 Billion of Euro !
Many beams offer great flexibility
SKA poster (multi-beams)
Many targets/users
Interference rejection
30-250 MHz
Polish extension of LOFAR - POLFAR
LBA
UBA
Why is radio astronomy important?
Explores fundamental physics using:
• the first photons set free in the universe after the “Big Bang”
•
the basic element, hydrogen – the 21cm line
• magnetic fields - polarisation imaging
• the most accurate clocks in the universe – millisecond pulsars
“Window” on matter in different phases
•
•
•
synchrotron radiation
maser emission
bremsstrahlung from thermal gas
Penetrates dust/gas:
• absorbs & scatters radiation in most other wavebands
Provides highest resolution images at any wavelength – VLBI
Very attractive research in fields of :
COSMOLOGY (large scale structure evolution), Exoplanets
Evolution of matter (+chemical), Extreme physical coditions
LIMITATIONS
Instruments (cost driven)
Foregrounds
Background (cosmic and local )
Maximum baseline length
Physical extension of radio sources + scattering
RFI
Ground based
observations
Interference level in 1.4 – 1.8 GHz band
TCfA in Piwnice Observatory
SED
Nature is kind to CMB cosmologists
CMB window ~30-200 GHz
Large area of the sky is accessed
but
the foreground sources are the problem
no variability,
local Universe only,
no evolution included
Foreground Components
J.L. Puget
(IAS, Orsay)
•
•
•
•
•
Local - Solar System (dust - zodiacal light)
Our Own Galaxy (extended emission and discrete sources)
Interstellar Medium (gas and dust)
Extragalactic objects (AGNs, SBGs, NGs)
Gravitational lensing
we need to
• Identify, measure contributions and estimate the total budget
as a function of position on the sky, angular resolution,
redshift, freqency
• But studying the foreground is important
and interesting by itself too !!!
Dunkley et al. (2010)
J.L. Puget
(IAS, Orsay)
Radio sources contribution is frequency dependent
J.L. Puget
(IAS, Orsay)
Foregrounds: low frequencies
SED
If power law nb
Power spec
Cl ~la
J.L. Puget
(IAS, Orsay)
Polarized or not
Degree of pol.
Synchrotron
Power law
b=-3
Power law
a=-3 ?
Polarized
Up to 40%
Free free
Power law
b=0
Power law
a=-3
Not polarized
Power law
a=-3 ?
Not polarized
Anomalous
dust emission
(PAH rotation ?)
Broad max
around 10 GHz
SZ
Constant
<140GHz
Poisson high l
Broad max
l=1000
Not polarized
Radio sources
Flat or rising RS
b >= 0
Poisson (a=0)
Polarized
Foregrounds high frequencies
SED
IS thermal
dust
emission
Power spec
Cl ~la
J.L. Puget
(IAS, Orsay)
Polarized
Degree of pol.
Modified BB
Peak around
150µm
Power law
a=-3
Yes
~5%
CIB
Multi temperature
Modified BB
peak around 150
µm
Poisson high l
Broad max
l=1000
Not polarized
SZ
Max at 350 GHz
Zero at 217 GHz
~Constant
<140GHz
Poisson high l
Broad max
l=1000
Not polarized
Modified BB
Peak at 25 µm
Very smooth
Ecliptic lat + solar
elongation dep.
Emission not
known to be
polarized
Zodiacal
emission
What observations are required ?
•
•
•
•
•
•
•
J.L. Puget
(IAS, Orsay)
CMB + foreground contribution
Wide range of frequencies ~1 GHz to ~5000 GHz
Lots of frequency channels
Total intensity and full polarization
Spectroscopy
High resolution data (diffuse maps & source surveys)
Local surveys for RFI, atmosphere, spillover, etc.
On all accessible instruments - space & ground based
Mostly single dishes with angular resolution (5’ -10’)
J.L. Puget
(IAS, Orsay)
J.L. Puget
(IAS, Orsay)
Simple observation:
Sky emission varies dramatically
with frequency …
… With non-trivial differences
between polarized and unpolarized
emission
Template Maps
J.L. Puget
(IAS, Orsay)
Synchrotron
Free-Free
Finkbeiner
Ha Map
Haslam 408
MHz
WMAP
K-Ka (I Map)
WMAP
K-band (Pol)
Thermal Dust
OBSERVATIONS SHOWING
THE DUST SPECTRUM
The Perseus Molecular Cloud
(Watson et al. 2005). The
spectum is the integrated flux
density in a 1.3o beam. The
spectral components are freefree, spinning dust and thermal
dust.
The LDN 1622 dark cloud ( Casassus et
al. 2006). The dust cloud is relatively
cool – at a temperature of ~15 K.
Strong discrete sources accounted / removed by Planck Mission
J.L. Puget
(IAS, Orsay)
1.4 GHz Source Counts (Hopkins 2000)
AGN steep
flat
starbursts
spirals
SKA EVLA HDF/COSMOS++ 1st/NVSS Cambridge
N(S) =No x S -1.5
dN/dS ~ S-5/2
dn/dno for S-S+DS
1.4 GHz uJy source counts (Schinnerer et al. 04)
E.Waldram Cambridge UK
5GHz
f(GHz)
~No
0.408
1.4
5.0
10.7
30.0
86.0
750
500
350
250
200
170
N(S) = No S
-3/2
Project OCRA S > 5mJy,
expected 10 – 25 x103 / sr
i.e. 3 to 7 sources / deg2
dN/dS = a S
-5/2
OCRA – One Centimetre Receiver
Array
OCRA collaboration
University of Manchester:
R. Battye, I. Browne, R. Davis, S. Lowe, M.
Peel and P. Wilkinson. Also E. Blackhurst,
C. Baines, J. Edgley, J. Kitching, D.
Lawson, J. Marshall and N. Roddis
Toruń Centre for Astronomy:
R. Feiler, M. Gawronski, A. Kus, B.
Pazderska, E. Pazderski, B.Roukema
University of Bristol:
A.Azareedh, M. Birkinshaw,
K. Lancaster
TCfA
a classical radio galaxy
gorąca plama
~100 kpc
lobe
core
jet
Counter jet
lobe
gorąca plama
log S
dżet
kontra dżet
core
log n
OCRA band
log S
10 mas
log n
Core of 3C273
T.Pearson et al. CALTECH
OCRA-p
OCRA-f
OCRA-p the OCRA prototype
OCRA-f
with cryostat open
What about the future
of RA at the TCfA ?
90m radio telescope
Hevelius
RT90
active
surface
Homology dwsign
Specifications
Optics: Cassegrain, Ritchey-Chretien
Optymalisation for: large field of view, high sensitivity,
low spill-over
Mount: Alt-Az (or hydraulic drives ?)
Precision: surface 0.5 mm RMS, pointing <10”
Receivers: ultra broad band, Tsys < 30K,
multi beam radio camera
Back-ends: all digital (data transver rate 4-10 Gb/s)
Receiving Systems
Multi beam receiver OCRA-f
on RT32m, at 30 GHz
Recivers in secondary focus of RT90+
BW 5-21 GHz
POL LHC & RHC
Sub-Bands 2 GHz
BW 1-3 GHz
Digital Back-ends
Radiometry
Polarimetry
Spectroscopy
PSRs
Transients
-1,5 m
0
+1,5m
49 outouts x 2 pol x
16 (1 GHz) sub-bands=>
1568 # chan. of ~1 kHz
resolution
Raw data ~5 TB / s
Optimal
setup in
a survey
mode
1-3 GHz
5-21 GHz
UHF (600-900 MHz)
3m
Concept of the reciver systems and FPGA digital back-ends
Research Programs a summary
VLBI (EVN +SKA)
Single dish research
An RTH Legacy project: “2CMS”
the 2-Centimetre Million Source survey
Extragalactic astronomy
Foregrounds
Clusters of galaxies
AGNs
Normal galaxies
IGM
Galactic astronomy
Pulsars
Transients
Active stars
Molecules
Magnetic fields
ISM
RT90
Proposed location =>
Radio telescope RT90+
Dębowiec
D = 110m
3D Model 3D, based on Z.Bujakowski concept of 70m antenna,
made by Janusz Mazurek and Roman Feiler from CA UMK
using Google SketchUp program
Organisation of the
National Centre for Radio Astronomy and Space
Engineering
Investmen from European and Regional Structure Funds
and the government Funds
Partners / participants
* EVN, JBCA.uk JIVE.nl MPIfR.d HU.se
1. CA UMK
2. Gdańsk University of Technology
3. Space Research Centre PAS
4. AO Jagiellonian University Cracow
5. Institute of Astronomy UZG
6. Poznan Super Computer and Networking Centre
7. Copernicus Astron. Centre PAS Warsaw
8. WAT, Warsaw
9. UTP, Bydgoszcz
Summary so far…..
• Radio technology developing at a great pace
- Several technical revolutions underway
- New large instruments underway
 subject is vibrant
• Radio astronomy will continue to make major
contributions to fundamental physics and
cosmology
Famous „Starry Night” by van Gogh
The artist vision of complex
interactions in our Universe
The End
Thank you for your attention
how to build a simple radio telescope with
SDR - Software Defined Radio
USB-2 Dongle
RTL2832U+R820T chips
Cost: ~10 Euro !
System Overview








Tuner: Rafael Microelectronics,
Inc. R820T
ADC/Demodulator Chip: Realtek,
Inc. RTL2832U
Superheterodyne receiver
I/Q Demodulation
Frequency Range: 24-1766 MHz
Max Sample Rate: 2.4 MS/s (3,2
MS/s)
Spectrum BW 2.4 (3.2 max) MHz
Interface USB-2
MIT Haystack Observatory
USB Dongle
• Block diagram
Reference to SRT project of the MIT Haystack Observatory
Dongle-Based SRT Schematic
Reference to SRT project of the MIT Haystack Observatory
SDR software (free)
For more details look at:
http://www.haystack.edu/edu/undergrad/srt/index.html
http://en.wikipedia.org/wiki/Software-defined_radio

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