[Aavso-photometry] [AAVSO-DIS] SN 2009dd

[Richard Huziak]

Hi Mario

That's the procedure I understand.  You'd treat the nucleus & galactic 
fuzz as a second star in the aperture and after the SN is gone, image 
again.  To be consistent, the same aperture size should be used in the 
reductions of different nights and the same area of the galaxy within 
the aperture.  I guess the secret would to be try to keep all things the 
same over all nights as possible. 

Just as an aside, can an 'unsharp masking' or similar nulling technique 
be used on a raw image to subtract out the galaxy, then photometry done 
after?  Just a thought.

rick

Mario Motta wrote:
> Hello all,
>
>   I was away at the NEAF meeting with gary Walker, got back last 
> night. I did take a set of images of NGC 4088, with the intent of 
> deriving a magnitude. What I found was the SN os right on top of the 
> core, just appears as a bump off the core. I have an image made which 
> I will post at my ATMOB site later tonight, also have a raw stack 
> unprocessed beyond flat and dark to derive a magnitude. however, not 
> sure how to do in this case. Anyone have an idea? The magnitude 
> derivation will be contaminated by the core of the galaxy. Do we have 
> to wait a couple of months till gone and then subtract out the 
> underlying galaxy?
>
> Mario Motta
>
> Richard Huziak wrote:
>> Is anyone working on the light curve of 11th mag type II SN 2009dd in 
>> NGC 4088, a very interesting, disturbed galaxy in UMa?  Tough 
>> photometrically - it is basically on top of the nucleus (2"W, 5"S), 
>> but short exposures might decrease the 'fuzz factor'.  Visually 
>> estimates would be good.  There is no sequence around NGC 4088, though.
>>
>>
>> Are all SN's added to VSX, btw?
>>

-- 
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Richard Huziak
Manufacturing Engineering
SED Systems
Saskatoon, SK, Canada
tel. (306) 933-1676
<huziak at SEDSystems.ca>
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