Hi David,
Yes, that works.
cheers,
Jane
David Berry wrote:
> Hi Jane,
> CADC require spectral axes to refer to the Barycentric
> rest frame. But the source velocity is recorded in the header in the
> LSR rest frame. So to compare them you need to get them into the same
> rest frame. If, after setting System to VRAD, you do:
>
> % wcsattrib fred.sdf set stdofrest lsr
>
> (where fred.sdf is your NDF cube), do things look better?
>
> David
>
>
> On 30 November 2010 12:41, Jane Buckle <[log in to unmask]> wrote:
>> Hi All,
>>
>> The JSA HARP/ACSIS reduced data come with the 3rd axis as frequency. After
>> using fits2ndf to get the ndf file, and then wcsattrib to set system vrad,
>> the velocity of the line is wrong. For instance, a cube with source velocity
>> 7.5km/s, as in the fits header, shows in gaia with a line in the centre of
>> the band around -10 km/s.
>>
>> Is there some default I need to change in the fits2ndf, or some attribute
>> that I need to set, to get the line at the correct velocity?
>>
>> Cheers,
>>
>> Jane
>>
>>
>> --
>> Dr Jane V. Buckle
>> Cavendish Astrophysics Group and Kavli Institute for Cosmology,
>> Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge
>> CB3 0HE
>> Tel: +44 (0)1223 746436
>>
--
Dr Jane V. Buckle
Cavendish Astrophysics Group and Kavli Institute for Cosmology,
Institute of Astronomy, University of Cambridge, Madingley Road,
Cambridge CB3 0HE
Tel: +44 (0)1223 746436
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