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Differences between revisions 11 and 17 (spanning 6 versions)

HERA 1mm array receiver

Rx	#	Pol	tuning range	Trx	IF	IF Bw	Gim	Status	Rem.
			[GHz]	[K]	[GHz]	[GHz]	[dB]
HERA1	9	H	215-272	110-380	4	1	~10
HERA2	9	V	215-241	120-340	4	1	~10		(1)

Comments: (1) HERA2 pixels 4 and 9 are instable and should be flagged in data processing. <CK 9-May-2014>

HERA is a heterodyne receiver array consisting of two arrays of 3x3 pixels with 24" spacing. The two arrays have orthogonal polarization (V, H) the two polarizations pointing at identical locations on the sky. HERA is equipped with a derotator allowing to follow a source in the sky maintaining the same "footprint". Over the range of tunable frequencies, the beamwidth varies between 12" and 9".

HERA manual, version 2.0 by Sievers et al. 2006
Schuster et al. 2004, A&A, 423, 1171 A 230 GHz Heterodyne Receiver Array for the IRAM 30m telescope (local copy)
Observations with HERA in combination with EMIR or MAMBO, are not possible.
HERA mixers are single-sideband mixers. The image sideband is rejected.
The nominal bandwidth is 1 GHz.
HERA has two local oscillators, one for each polarization. Simultaneous observations of e.g. the 12CO and 13CO 2-1 lines are hence possible with both polarisations. Note that, in addition, the C18O 2-1 line lies within the 1GHz bandpass next to the 13CO line.

-  ⇤ ← Revision 11 as of 2009-10-06 22:34:42 → 
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+   ← Revision 17 as of 2014-06-23 13:35:00 → ⇥
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-Deletions are marked like this.
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 Line 5:
-||HERA1     || 9|| H       || 215-272            || 110-380     ||  4          || 1           || ~10 || {{attachment:haken.gif}} || '''2.,3.'''||
||HERA2     || 9|| V       || 215-241            || 120-340     ||  4          || 1           || ~10 || {{attachment:haken.gif}} || '''2.,3.'''||
+||HERA1     || 9|| H       || 215-272            || 110-380     ||  4          || 1           || ~10 || {{attachment:haken.gif}} || ||
||HERA2     || 9|| V       || 215-241            || 120-340     ||  4          || 1           || ~10 || {{attachment:haken.gif}} || (1) ||

Comments: (1) '''HERA2 pixels 4 and 9 are instable and should be flagged in data processing.''' <CK 9-May-2014>
-Line 15:
+Line 17:
+  * HERA mixers are single-sideband mixers. The image sideband is rejected.

  * The nominal bandwidth is 1 GHz. 

  * HERA has two local oscillators, one for each polarization. Simultaneous observations of e.g. the 12CO and 13CO 2-1 lines are hence possible with both polarisations. Note that, in addition, the C18O 2-1 line lies within the 1GHz bandpass next to the 13CO line.