Yebes Observatory 40-m Telescope
Telescope: Nasmyth-Cassegrain 40-m diameter telescope. Further information about the optics.
Location: Yebes, 50 km north-east of Madrid.
Latitude: 40º 31' 30.75" N, longitude: 03º 05' 19.41" W, elevation: 980 meters.
FROM JANUARY 2019
Receivers characteristics and spectrometers:
Band Frequency range Receiver temp. Receiver type Polarization LO tunability HPBW (") Spectrometer Bandwidth Spectral Resolution eta_a eta_mb eta_f Jy/K Tmb/Ta* Ta*(FullMoon) [K]
C 4.8 - 6.7 GHz 30 K HEMT Dual (circular pol.) Yes 307 FFTS 1x500 MHz 500 MHz, 100 MHz 30 kHz, 6.1 kHz 0.60 0.96 0.87 3.2 1.0
X 8.15 - 8.65 GHz 30 K HEMT Dual (circular pol.) No 224
K 21.0 - 25.0 GHz 50 K HEMT Dual (circular pol.) Yes 84 FFTS 1x500 MHz 500 MHz, 100 MHz 30 kHz, 6.1 kHz 0.50 0.70 0.93 4.1 1.3
Q 31.5 - 50.0 GHz 50 K HEMT Linear, H/V Yes 42 FFTS 8x2.5 GHz 18 GHz 38 kHz 0.41 0.49 0.90 4.8 1.8 230
W 72 - 90.5 GHz 60 K HEMT Linear, H/V Yes 19 FFTS 8x2.5 GHz 18 GHz 38 kHz 0.21 0.25 0.89 9.3 3.6 215
UP TO JANUARY 2019
The 40-m radiotelescope is equipped with HEMT receivers for the 2.2-50 GHz range, and a SIS receiver for the 85-116 GHz range. However for single dish observations only the frequency ranges in the table below can be observed. Observations at frequencies below 4.8 GHz may have strong radiofrequency interferences (see e.g. López-Pérez & García Carreño 2017), and for frequencies above 100 GHz are subject to low efficiency. Observations at X band (8 GHz) are at a fixed frequency and hence cannot be corrected for Doppler shifts.
Receivers characteristics:
Band Frequency range Receiver temp. Receiver type Polarization LO tunability HPBW (")
C 4.8 - 6.7 GHz 30 K HEMT amplifier Dual (circular pol.) Yes 307
X 8.15 - 8.65 GHz 30 K HEMT amplifier Dual (circular pol.) No 224
K 21.0 - 25.0 GHz 50 K HEMT amplifier Dual (circular pol.) Yes 84
Q 41.0 - 49.0 GHz 50 K HEMT amplifier Dual (circular pol.) Yes 42
W 85 - 100 GHz 50 - 60 K SIS mixer Single (linear pol.) Yes 19
Receivers at different frequencies cannot be used simultaneously except for the 22 and 45 GHz receivers which can be used at the same time.
Spectrometers:
The backends for spectral line observations consist of Fast Fourier Transform spectrometers (FFTS) with the following characteristics:
Band Frequency range Spectrometer Bandwidth Spectral Resolution
C 4.8 - 6.7 GHz FFTS 1x500 MHz 500 MHz, 100 MHz 30 kHz, 6.1 kHz
K 21.0 - 25.0 GHz FFTS 1x2.5 GHz 2 GHz 38 kHz
Q 41.0 - 49.0 GHz FFTS 4x2.5 GHz 9 GHz 38 kHz
W 72.0 - 90.0 GHz FFTS 1x500 MHz 500 MHz, 100 MHz 30 kHz, 6.1 kHz
Observing modes:
Position switching and frequency switching observing modes. In the near future, on-the-fly observations will be available.
Continuum observations, only for pointing and focus. In addition, pointing and focus can be checked using astronomical masers by means of pseudo-continuum observations.
Information about the atmospheric transmission in Yebes.
Observing procedures:
Observations will be performed by Yebes operators using macros/procedure defined and prepared by the observer with the help of the Yebes astronomer on duty.