A 279-381 GHz receiver for the new APEX telescope ISTT 2005 Chalmers, GöteborgMay 2-4, 2005 A...
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Transcript of A 279-381 GHz receiver for the new APEX telescope ISTT 2005 Chalmers, GöteborgMay 2-4, 2005 A...
A 279-381 GHz receiver for the new APEX telescope
ISTT 2005 Chalmers, GöteborgMay 2-4, 2005
A 279-381 GHz SIS receiver A 279-381 GHz SIS receiver for the APEX telescopefor the APEX telescope
C. Risacher1, V. Belitsky1, I. Lapkin2, R. R. Monje1, V. Vassilev1, M . Pantaleev1, A. Pavolotsky1, K.-Å Johansson1, L. G. Gunnarsson1, M. Svensson1, M. Fredrixon1, E.
Sundin1, V. P. Robles1, D. Medelin, M.Hagström 1, R. Booth 1
1 Group for Advanced Receiver Development (GARD), Radio & Space Science Department with Onsala Space Observatory, Chalmers University of
Technology, Gothenburg, Sweden2 Institute of Applied Physics, Russian Academy of Sciences
46 Ulyanov str.,603950 Nizhny Novgorod, Russia
A 279-381 GHz receiver for the new APEX telescope
ISTT 2005 Chalmers, GöteborgMay 2-4, 2005
Band RF range (GHz) IF (GHz) DSB Noise
APEX-1 G: 211-275 4-8 G: 25K
B: 40K
APEX-2 G: 275-370 4-8 G: 35K
B: 50K
APEX-3 G: 385-500
B: 455-500
4-8 G: 70K
B: tbd
APEX-4 G: 602-720 4-8 G: 110K
B: 170K
APEX-5 G: 787-950 4-8 G: 175K
B: tbd
APEX-T1 G: 1030 (50) 4-8 G: 230 K
APEX-T2 G: 1320 (140) tbd G: 550 K
APEX-T3 G: 1500 (140) tbd G: 650 K
APEX receivers: Heterodyne InstrumentationAPEX receivers: Heterodyne Instrumentation
A 279-381 GHz receiver for the new APEX telescope
ISTT 2005 Chalmers, GöteborgMay 2-4, 2005
RF tuning range: 279-381 GHz (no possibilities to extend this range except by changing the Gunn oscillator.
IF frequency: 4-8 GHz. At the present time the backend are limiting the IF band to 5-7 GHz
Noise temperature:
40 ± 10 K (DSB) across RF band
Optics Flat and active cold mirrors + 9 warm mirrors to obtain a beamwaist of 6 mm to match the APEX Cassegrain waist
Cryogenics Old SEST SESIS cryostat. Closed cycle cooling system. 1 compressor CTI 8500 with cold head CTI1020 to produce 80K and 12K. 1
compressor Quantum J20 for 4K stage. Cooling time of 14 hours.
Calibration External calibration unit in Cabin A: See corresponding documentation
Computer control
Control system using National Instrument Fielpoint modules. Ethernet connection to the telescope network. Virtually possible to tune from
anywhere.
Alarms If temperature of mixer block exceed 4.9 K, automatic shutdown of the receiver. Bias of SIS is set to 0 mV, and magnetic coil current is
also set to 0 mA.
A 279-381 GHz receiver for the new APEX telescope
ISTT 2005 Chalmers, GöteborgMay 2-4, 2005
230 GHz channel 345 GHz channel
Outside part of cryostat Inner part of cryostat
First light receiver with closed cycle machine
A 279-381 GHz receiver for the new APEX telescope
ISTT 2005 Chalmers, GöteborgMay 2-4, 2005
Signal from input window
Flat mirror
Active mirror
Mixer block
4-8 GHz LNA
A 279-381 GHz receiver for the new APEX telescope
ISTT 2005 Chalmers, GöteborgMay 2-4, 2005
A 279-381 GHz receiver for the new APEX telescope
ISTT 2005 Chalmers, GöteborgMay 2-4, 2005
A 279-381 GHz receiver for the new APEX telescope
ISTT 2005 Chalmers, GöteborgMay 2-4, 2005
780
mm
400mm
Nasmyth flange
Horn apertureposition
ellipsoid mirror
switching active mirrorFocal distance 660mm
A 279-381 GHz receiver for the new APEX telescope
ISTT 2005 Chalmers, GöteborgMay 2-4, 2005
A 279-381 GHz receiver for the new APEX telescope
ISTT 2005 Chalmers, GöteborgMay 2-4, 2005
Laboratory test cryostat with liquid helium
Mixer block
4-8 GHz Isolator 4-8 GHz IF LNA
Cold teflon lens
200 m Zitex IR filter
3 mm Teflon window with
circular corrugations
A 279-381 GHz receiver for the new APEX telescope
ISTT 2005 Chalmers, GöteborgMay 2-4, 2005
Mixer block description
A 279-381 GHz receiver for the new APEX telescope
ISTT 2005 Chalmers, GöteborgMay 2-4, 2005
A 279-381 GHz receiver for the new APEX telescope
ISTT 2005 Chalmers, GöteborgMay 2-4, 2005
A 279-381 GHz receiver for the new APEX telescope
ISTT 2005 Chalmers, GöteborgMay 2-4, 2005
A 279-381 GHz receiver for the new APEX telescope
ISTT 2005 Chalmers, GöteborgMay 2-4, 2005
0
50
100
150
200
240 260 280 300 320 340 360 380
Uncorrected noise temperature for 4 mixer blockswith twin junctions 30 Ohm probe
MB2-n
MB2-o
MB1-n
MB1 - n
No
ise
te
mp
era
ture
(K
)
LO frequency (GHz)
3*hu/ k
2*hu/ k
Apex band 2
Toptics 12 K
Loptics 5%
TIF 10-20 K
Gmix 0 - 3 dB
Tmix 10 K
A 279-381 GHz receiver for the new APEX telescope
ISTT 2005 Chalmers, GöteborgMay 2-4, 2005
A 279-381 GHz receiver for the new APEX telescope
ISTT 2005 Chalmers, GöteborgMay 2-4, 2005
A 279-381 GHz receiver for the new APEX telescope
ISTT 2005 Chalmers, GöteborgMay 2-4, 2005
0 mA coil current : Strong DC Josephson effect
A 279-381 GHz receiver for the new APEX telescope
ISTT 2005 Chalmers, GöteborgMay 2-4, 2005
12.5 mA coil current : DC Josephson effect suppressed
A 279-381 GHz receiver for the new APEX telescope
ISTT 2005 Chalmers, GöteborgMay 2-4, 2005
With LO power applied
A 279-381 GHz receiver for the new APEX telescope
ISTT 2005 Chalmers, GöteborgMay 2-4, 2005
Control system
A 279-381 GHz receiver for the new APEX telescope
ISTT 2005 Chalmers, GöteborgMay 2-4, 2005
A 279-381 GHz receiver for the new APEX telescope
ISTT 2005 Chalmers, GöteborgMay 2-4, 2005
Cooling system
A 279-381 GHz receiver for the new APEX telescope
ISTT 2005 Chalmers, GöteborgMay 2-4, 2005
A 279-381 GHz receiver for the new APEX telescope
ISTT 2005 Chalmers, GöteborgMay 2-4, 2005
A 279-381 GHz receiver for the new APEX telescope
ISTT 2005 Chalmers, GöteborgMay 2-4, 2005
0
50
100
150
200
250
300
0 5 10 15 20
Apex first light receiver cool down16-12-04
77 K stage20 K stage4 K stage
Te
mp
era
ture
(K
)
Time (Hours)