MPIfR APEX Instrumentation
Bernd Klein
MPIfR APEX Instrumentation
Bernd Klein
Bernd Klein, Ringberg 2018
MPIfR APEX instrumentationMPIfR APEX instrumentation
Bernd Klein, Ringberg 2018
Overview of my talk:
LAsMATHz channel
CHAMP+ HFA CHAMP+ LFA
(PI 230)
FLASH 460 LAsMA FLASH 230
FLASH PI 850
A-MKID HFA
A-MKID LFA
PI 230 Receiver (mm-VLBI)PI 230 Receiver (mm-VLBI)
Bernd Klein, Ringberg 2018
Technical specifications:
➔ 2SB SIS mixer from IRAM (NOEMA spin-off)➔ dual polarization operation ➔ RF range: 195 – 270 GHz➔ Receiver noise temperature: 50 – 60 K (SSB) ➔ VDI solid-state LO source➔ total IF bandwidth: 2x 2x 8 GHz = 32 GHz➔ PI FFTS4G spectrometer, 512k spectral channels➔ Fully remote controlled (frequency change within seconds)➔ Pathfinder for new mm-VLBI observing technologies➔ in operation since 12 / 2015
3D model and photoof the PI 230 receiver
PI 230 – a state-of-the-art receiver for mm-VLBI and spectroscopy
The new FLASH receiver The new FLASH receiver
Bernd Klein, Ringberg 2018
A short history:
2005: Workhorse for the APEX commissioning, operatingin the 460 and 810 GHz atmospheric windowsSpectrometer: 2 x 1 GHz bandwidth (FFTS)
2010: With CAMP+ covering the 810 GHz science with 7 pixels,FLASH was downgraded to 345 and 460 GHzSpectrometer: 4 x 1,5 GHz (AFFTS)
2012: Upgraded with state-of-the-art 2SB ALMA mixers for the345 GHz and 460 GHz bands.Spectrometer: 8 x 2,5 GHz bandwidth (XFFTS)
2018: Upgrade with new IRAM (230 GHz) and ALMA band 8(460 GHz) 2SB mixers (facility mode).Additional 850 GHz band (PI mode).Spectrometer: 16 x 4 GHz bandwidth (dFFTS4G)
FLASH – a First Light APEX Submillimeter Heterodyne instrument
FLASH @ APEX, 2005
S. Heyminck, et al., A&A, 454 (2006)
The new FLASH receiver The new FLASH receiver
Bernd Klein, Ringberg 2018
new FLASH: facility mode new FLASH: PI mode
230 GHz band:
• VDI LO unit, tuning range: 200 – 270 GHz
• dual-polarization setup
• IRAM SIS 2SB mixer (PI230), IF bandwidth 4 – 12 GHz total IF bandwidth: 2x 2x 8 GHz = 32 GHz
• Receiver noise temperature: 50 – 60 K
460 GHz band:
• VDI LO unit, tuning range: 385 – 510 GHz
• dual-polarization setup
• ALMA band 8 SIS 2SB mixer, IF bandwidth 4 – 8 GHz total IF bandwidth: 2x 2x 4 GHz = 16 GHz
• Receiver noise temperature: 80 – 150 K
See Poster by Christopher Heiter !
The new FLASH receiver The new FLASH receiver
Bernd Klein, Ringberg 2018
new FLASH: PI mode
PI mode expansion 850 GHz band:
• broadband VDI hybrid LO unit, tuning range: 780 – 950 GHz
• dual-polarization setup
• ALMA band 9 mixer baseline: goal: (SRON cooperation) DSB 2SB IF bandwidth 4 – 8 GHz 4 – 12 GHz total IF bandwidth: 8 GHz 32 GHz
• Receiver temperature: 200 – 500 K 600 – 1000 K
PI 850 GHz
Optics Design
filter wheel
460 GHz
230 GHz
See Poster by Christopher Heiter !
Upgrade LAsMAUpgrade LAsMA
Bernd Klein, Ringberg 2018
LAsMA – the Large APEX subMillimeter Array for the 345 GHz atmospheric window
Technical specifications:
➔ 7-pixel single polarization heterodyne array 7x 345 GHz with state-of-the-art IRAM 2SB mixers
➔ RF range: 270 – 370 GHz➔ Receiver noise temperature (SSB): 80 – 100K ➔ Side-band separation (IF: 4 – 8 GHz): > 15 dB➔ VDI solid-state LO ➔ K-mirror for image de-rotation➔ Frontend software for auto-tuning and remote control➔ in operation since 2016
➔ Upgrade work (April 2018):
➔ For now: IF bandwidth: 7x 2x 4 GHz = 56 GHz➔ Upgrade: replacement of the 4 – 8 GHz IF coupler by
new 4 – 12 GHz IF-coupler (> 15 dB) IF bandwidth: 7x 2x 8 GHz = 112 GHz
➔ Upgrade: FFTS4G spectrometer to process 112 GHz band- width with up to 1,8 million spectral channels
Top: 7x IRAM 2SB mixers
Left: LAsMA at APEX (2017)
LAsMA – the new THz channelLAsMA – the new THz channel
Bernd Klein, Ringberg 2018
Technical specifications:
➔ Spin-off from our Herschel involvment (HIFI band 5 mixer, DSB) ➔ Co-aligned to the central pixel of LasMA for pointing reference ➔ RF range: 990 – 1050 GHz➔ Receiver noise temperature (DSB): 400 – 550 K➔ VDI solid-state LO source➔ IF bandwidth: 4 – 8 GHz➔ PI IF processor and FFT spectrometer
➔ Strong operation boundaries:- requires best weather conditions (PWV < 0.3 mm)- pointing requirements are demanding (main beam: 6'' only)- telescope surface must be very good (surface rms < 15 µm)
MPIfR PI 1.05 THz Receiver (2009) (A-cabin, PI position #2)
CHAMP+ (2007 - 2016)CHAMP+ (2007 - 2016)
Bernd Klein, Ringberg 2018
CHAMP+ – dual color 2 x 7 pixel heterodyne arrayfor the 450 µm and 350 µm atmospheric windows
beam-path
first B-cabin mirror (M2)
elevation bearing
flat folding mirror
mirror M3
LO-unit
vacuum-vessel
sub-array modules
cooling-machine
lifter-mechanism
R. Güsten, et al., SPIE, 7020 (2008)
Technical specifications (2007 - 2016):
➔ Two 7-pixel sub-arrays:620 – 720 GHz and 780 – 950 GHz
➔ simultaneous observations possible➔ fixed tuned DSB SIS-mixers (SRON)➔ main optics cooled to 15K➔ quasi-optical LO-injection with
Martin-Puplett interferometer as Diplexer➔ SSB-filter for both sub-arrays (> 15 dB)➔ image de-rotator ➔ 2 GHz (2,8 GHz) IF-bandwidth per channel➔ in operation since 2007
Upgrade of CHAMP+Upgrade of CHAMP+
Bernd Klein, Ringberg 2018
CHAMP+ withold LO unit (2015)
• Upgrade of both arrays with state-of-the-art SRON DSB mixers (2017)
• Replacement of the old LO unit by VDI solid-state LO sources, and elimination of the diplexers (2018) ( more IF bandwidth)→
• New frontend electronic and software (auto-tuning, remote control)
• Connect to LAsMA IF processor and spectrometer
LFA: HFA:
RF range [GHz] 620 – 710 775 – 855
TRx SSB [K] 250 – 400 600 – 1000
IF bandwidth [GHz] 7 x 4 GHz 7 x 4 GHz
CHAMP+ – dual color 2 x 7 pixel heterodyne arrayfor the 450 µm and 350 µm atmospheric windows
CHAMP+ with new VDI LO unit (2018)
A-MKID cameraA-MKID camera
Bernd Klein, Ringberg 2018
Technical specifications:
➔ Dual color APEX direct detection camera:- LFA: 353 GHz ( 34 GHz HP width)- HFA: 865 GHZ (100 GHz HP width)
➔ Squared field of view: 15 x 15 arcmin² ➔ Pixel spacing: 1Fλ➔ Hexagonal arrangement➔ Number of Pixels:
- LFA: 3520 pixel- HFA: 21600 pixel
➔ Detectors operating with sensitivities dominatedby the sky background
➔ NEFD per pixel (goal):- LFA: 50 mJy s (0.3 – 1.0 mm PWV)- HFA: 1650 mJy s (0.3 – 0.5 mm PWV)
Present Status:
Due to insufficient sensitivities that could not be fixed at APEX, we decide to sent A-MKID back to Bonn for further investigations.A-MKID is currently being cooled down.Extensive laboratory tests are planned for the coming weeks.
A-MKID at laboratory tests in Bonn. (08. March 2018)
A-MKID – superconducting pair breaking detector
MPIfR 8 GHz IF processorMPIfR 8 GHz IF processor
Bernd Klein, Ringberg 2018
Technical specifications:
➔ The new IF processor based on a modular approach.➔ Fully integrated circuit with amplifier, filter, mixer,
programmable attenuators, and total-power detectors.➔ Fully remote controlled by SCPI protocol.
➔ Input frequency: 1 x (4 – 12 GHz)
Output frequency: 2 x (0 – 4 GHz)
The new 8 GHz IF processor modules are designed for the latest version of our wide-band FFT spectrometer
Inside the 8 GHz IF modules LO input 12 GHz
LO input 8 GHz
out: 0 – 4 GHz (8 – 12 GHz part)
out: 0 – 4 GHz (4 – 8 GHz part)
IF input 4 – 12 GHz
MPIfR dFFTS4G spectrometerMPIfR dFFTS4G spectrometer
Bernd Klein, Ringberg 2018
Technical specifications:
➔ Input bandwidth: 2 x 4 GHz (0 – 4 GHz)➔ Spectral channels: 2 x 64k ➔ Spectral resolution: 71 kHz (ENBW)➔ Power consumption: max. 70 W (~9 W / GHz)
Photo of the dFFTS4G spectrometer board
dFFTS4G