Differences between revisions 10 and 13 (spanning 3 versions)
Revision 10 as of 2009-10-06 22:25:39
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Revision 13 as of 2012-09-04 18:53:44
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Deletions are marked like this. Additions are marked like this.
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||'''Rx''' ||#||'''Pol'''|| '''tuning range''' || '''Trx''' || '''IF''' || '''IF Bw''' || '''Gim''' || '''Rem.''' ||
|| || || || '''[GHz]''' || '''[K]''' || '''[GHz]''' || '''[GHz]''' || '''[dB]''' || ||
||HERA1 || 9|| H || 215-272 || 110-380 || 4 || 1 || ~10        || '''2.,3.'''||
||HERA2 || 9|| V || 215-241 || 120-340 || 4 || 1 || ~10        || '''2.,3.'''||
||'''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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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).

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

haken.gif

HERA2

9

V

215-241

120-340

4

1

~10

haken.gif

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 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).

HeraforAstronomers (last edited 2015-05-28 08:55:59 by CarstenKramer)