<font face="Verdana, Arial, Helvetica" size="2">Mar Mezcua updated #11945<br />
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BPASS complains about the IFs<br />
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<div style="margin-left: 40px;">Ticket ID: 11945</div>
<div style="margin-left: 40px;">URL: <a href="https://help.nrao.edu/staff/index.php?/Tickets/Ticket/View/11945">https://help.nrao.edu/staff/index.php?/Tickets/Ticket/View/11945</a></div>
<div style="margin-left: 40px;">Name: Mar Mezcua</div>
<div style="margin-left: 40px;">Email address: <a href="mailto:mmezcua@iac.es">mmezcua@iac.es</a></div>
<div style="margin-left: 40px;">Creator: User</div>
<div style="margin-left: 40px;">Department: AIPS Data Reduction</div>
<div style="margin-left: 40px;">Staff (Owner): -- Unassigned --</div>
<div style="margin-left: 40px;">Type: Issue</div>
<div style="margin-left: 40px;">Status: Open</div>
<div style="margin-left: 40px;">Priority: Default</div>
<div style="margin-left: 40px;">SLA: NRAO E2E</div>
<div style="margin-left: 40px;">Template group: Default</div>
<div style="margin-left: 40px;">Created: 19 April 2018 12:51 PM</div>
<div style="margin-left: 40px;">Updated: 19 April 2018 12:51 PM</div>
<div style="margin-left: 40px;">Reply due: 23 April 2018 12:51 PM (4d 0h 0m)</div>
<div style="margin-left: 40px;">Resolution due: 13 January 2021 12:00 AM (999d 11h 9m)</div>
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Hi,<br /><br />I'm going through the data reduction of a VLBA dataset which has <span><span>two IFs, each with a very different frequency (4.4 GHz and 7.6 GHz). To load the UVDATA I use >fitld separating IF1 and IF2. This went fine and if I do >listr in the IF1 dataset I get:<br /></span></span><br />
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<div>FQID IF# Freq(GHz) BW(kHz) Ch.Sep(kHz) Sideband Bandcode<br /> 1 1 4.41200000 128000.0078 500.0000 1</div><br />
which is OK. Yet, when doing >imheader, the terminal returns:<br /><br />AIPS 1: Image=MULTI (UV) Filename=NGC5252_4GHz.UVDATA. 1<br />AIPS 1: Telescope=VLBA Receiver=VLBA<br />AIPS 1: Observer=BL226A User #= 2<br />AIPS 1: Observ. date=23-MAR-2016 Map date=03-APR-2018<br />AIPS 1: # visibilities 223697 Sort order TB<br />AIPS 1: Rand axes: UU-L-SIN VV-L-SIN WW-L-SIN TIME1 SUBARRAY<br />AIPS 1: SOURCE FREQSEL INTTIM GATEID ANTENNA1 ANTENNA2<br />AIPS 1: CORR-ID<br />AIPS 1: ----------------------------------------------------------------<br />AIPS 1: Type Pixels Coord value at Pixel Coord incr Rotat<br />AIPS 1: COMPLEX 3 1.0000000E+00 1.00 1.0000000E+00 0.00<br />AIPS 1: STOKES 4 -1.0000000E+00 1.00 -1.0000000E+00 0.00<br />AIPS 1: FREQ 256 4.4120000E+09 1.00 5.0000000E+05 0.00<br />AIPS 1: IF 2 1.0000000E+00 1.00 1.0000000E+00 0.00<br />AIPS 1: RA 1 00 00 00.000 1.00 0.000000 0.00<br />AIPS 1: DEC 1 00 00 00.000 1.00 0.000000 0.00<br />AIPS 1: ----------------------------------------------------------------</div><br />
<span><span><span>as if there were 2IFs.<br /><br /></span></span></span><br />
<div>IF2 is of course empty, so when doing the calibration I specify bif 1; eif 1 in all tasks.</div><br />
<div>However, when arriving to the bandpass calibration AIPS complains about having 2 IFs and bpass doesn't run. I specify:</div><br />
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<div>bpassprm(10)=2<br />ichansel 5,256,1,1</div><br />
<div>so that it uses only IF1, however it still complains:<br />localh> BPASS1: Dividing the spectral data by channel 0<br />localh> BPASS1: BPCOPY: copied 7308 vis records for bandpass fitting<br />localh> BPASS1: CHNCOP: REQUESTED TOO MANY IFS : 2> 1<br />localh> BPASS1: Purports to die of UNNATURAL causes</div><br />
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<span><span></span><br />I have redone the calibration without specifying bif 1;eif 1 in the previous calibration steps (the bandpass is the last step I do before the imaging), and I've tried also not to specify the IF for normalizing the amplitude in >bpass, but it doesnt' work, >bpass keeps on complaining. Any idea why?<br /><br />Thanks,<br />Mar</span>
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