Opened 14 years ago

Closed 13 years ago

#231 closed defect (fixed)

Spurious results from scans.opacity()

Reported by: martin.cordiner@… Owned by: Malte Marquarding
Priority: normal Milestone: ASAP 3.0
Component: General Version:
Severity: major Keywords: opacity correction
Cc:

Description

I've been performing opacity corrections on my spectra using scans.opacity(tau), with tau=0.07, but the output scantable has incorrect T values. An example scantable is attached, recorded at an elevation of about 25 degrees. The opacity correction factor should be about 1.19, but when I use scans.opacity(tau), IF1 gets multiplied by about a factor of about 16!

Note however, the scans.opacity() command appears to work correctly when operating on a single IF (using selector.set_ifs()).

Attachments (1)

test_scantable.tgz​ (469.0 KB ) - added by Martin A. Cordiner <martin.cordiner@…> 14 years ago.
Mopra scantable

Download all attachments as: .zip

Change History (6)

by Martin A. Cordiner <martin.cordiner@…>, 14 years ago

Attachment: test_scantable.tgz​ added

Mopra scantable

comment:1 by Malte Marquarding, 14 years ago

Owner: changed from Malte Marquarding to Malte Marquarding
Status: new → assigned

comment:2 by Malte Marquarding, 14 years ago

A quick question. Did you build asap from source or know how to do it? I think I know what is wrong and you could patch it.

comment:3 by Malte Marquarding, 14 years ago

Hi,

Thanks for your reply. My ASAP installation was performed by sys admin here, who I believe built it from source. I have been able to work around the problem by calculating my own opacity corrections and using the scale() command, so I probably won't need to do any further opacity corrections with my current Mopra data.

Cheers,

Martin

comment:4 by Malte Marquarding, 14 years ago

Ok, I will add the fix to the next release then.

comment:5 by Malte Marquarding, 13 years ago

Resolution: → fixed
Status: assigned → closed
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