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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

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 is working in single sideband mode (1 GHz Bandwidth). That means you cannot detect for a given channel the two sidebands at once. However you can use different frequencies for the two sets of polarizations . In this mode and by using the FTSs you can use the polar 1 (9 single polarization pixels, for ex in LSB) for 12CO(2-1) and polar 2 (another 9 single pol pixels, also in LSB) for simultaneous covering of 13CO(2-1) and C18O(2-1). This mode is interesting for galactic observations as it gives you all three lines simultaneously and therefore with good observing efficiency and good cross calibration - although each line as said only in single polarization).

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+   ← Revision 13 as of 2012-09-04 18:53:44 → ⇥
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+==== HERA 1mm array receiver ====
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- * Eight single pixel receivers A,B,C,D, and the 3x3 dual-polarisation HERA receiver are installed in the [http://www.iram.es/IRAMES/telescope/telescopeSummary/receiver6.html receiver cabin].
+||'''Rx''' ||#||'''Pol'''|| '''tuning range''' || '''Trx'''   || '''IF'''    || '''IF Bw''' || '''Gim'''  || '''[[http://www.iram.es/IRAMES/mainWiki/TelescopeSystemStatus#HERA|Status]]''' || '''Rem.''' ||
||         ||  ||       || '''[GHz]'''        || '''[K]'''   || '''[GHz]''' || '''[GHz]''' || '''[dB]''' || || ||
||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}} || ||
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+Line 8:
- * Four of the 8 A,B,C,D receivers can be used simultaneously. HERA cannot be combined with other receivers.
+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".
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+Line 10:
-||'''Rx''' ||#||'''Pol'''|||||||||| '''Rx combinations''' ||'''tuning range''' || '''Trx'''   || '''IF'''    || '''IF Bw''' || '''Gim'''  || '''Rem.''' ||
||         ||  ||       || '''AB'''  || '''CD'''  || '''AD'''  || '''BC'''  || ||'''[GHz]'''        || '''[K]'''   || '''[GHz]''' || '''[GHz]''' || '''[dB]''' || ||
||HERA1     || 9|| H       ||   ||   ||   ||   || X || 215-272            || 110-380     ||  4          || 1           || ~10        || '''2.,3.'''||
||HERA2     || 9|| V       ||   ||   ||   ||   || X || 215-241            || 120-340     ||  4          || 1           || ~10        || '''2.,3.'''||
+  * [[http://www.iram.es/IRAMES/otherDocuments/manuals/HERA_manual_v20.pdf|HERA manual, version 2.0]] by Sievers et al. 2006
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+Line 12:
- * [http://www.iram.es/IRAMES/groups/receiver/receiver.html More information on the heterodyne receivers.]
+  * [[http://esoads.eso.org/abs/2004A%26A...423.1171S|Schuster et al. 2004, A&A, 423, 1171]] A 230 GHz Heterodyne Receiver Array for the IRAM 30m telescope ([[http://www.iram.es/IRAMES/otherDocuments/manuals/0179hera.pdf|local copy]])

  * Observations with HERA in combination with EMIR or MAMBO, are not possible. 

HERA is working in single sideband mode (1 GHz Bandwidth). That means you cannot detect for a given channel the two sidebands at once. However you can use different frequencies for the two sets of polarizations . In this mode and by using the FTSs you can use the polar 1 (9 single polarization pixels, for ex in LSB) for 12CO(2-1) and polar 2 (another 9 single pol pixels, also in LSB) for simultaneous covering of 13CO(2-1) 
and C18O(2-1). This mode is interesting for galactic observations as it gives you all three lines simultaneously and therefore with good observing efficiency and good cross calibration - although each line as said only in single polarization).