[vsnet-chat 2660] Re: NSV4223 Pyxidis

["PETER F WILLIAMS" <PFWILLIAMS@onaustralia.com.au>]

Hi Andrew and All,

NSV4223 is certainly a large amplitude variable.  I made my first
observation of this star in 1996 January but did not begin to follow it
regularly until 1997 April when I noticed just much it had brightened.

Listed below are my observations through to the end of 2000 January in JD
format as shown in Andrew's message.  All these observations have been
included in my monthly reports to the VSS RASNZ and are therefore available
from the VSS database.  My observations of early February agree with the
faintness indicated by Andrew.  When NSV4223 fades, it certainly declines
very quickly, a bit like an RCB star but I feel it is a pulsating red
variable.  A period near 325 days seems likely.

I have used GSC magnitudes for all estimates of this star and tend to
agree with Andrew that the GSC mags are too faint (but they do make my
telescope perform very well!).


NSV4223 PYX  Observations by Peter Williams.

JD		MAG

2450107.0200   14.6	
2450543.9833   10.4	
2450546.9792   10.2	
2450554.9431   10.5	
2450565.9278   11.0	
2450595.9465   12.2	
2450606.8986   13.1	
2450608.9160   13.2	
2450825.0146   11.5	
2450839.0194   11.5	
2450858.9826   10.9	
2450891.9757   11.0	
2450918.0153   11.6	
2450931.9931   12.5	
2450956.9431   14.8	
2450978.8861   <15.0	
2450982.9222   <13.5	
2450992.8938   <13.5	
2451146.1813   11.6	
2451159.0285   11.5	
2451175.0222   11.3	
2451184.0118   11.1	
2451185.0139   11.3	
2451189.0097   11.5	
2451193.9944   11.5	
2451195.9951   11.5	
2451203.9979   11.6	
2451226.9750   12.2	
2451250.9722   13.2	
2451260.9597   13.8	
2451279.8993   14.9	
2451287.9750   15.0	
2451300.9507   13.9	
2451315.9181   13.8	
2451330.9486   13.7	
2451342.9208   13.8	
2451349.9000   13.7	
2451363.8736   14.4	
2451511.0667   10.8	
2451525.0139   11.1	
2451528.0056   11.1	
2451548.0542   11.7	
2451554.0104   11.7	
2451563.9722   12.2	

All these estimates have been made using the 30cm newtonian at Heathcote. 
NSV4223 is an interesting star to observe and a reliable sequence would
help.
Trust you find these of assistance.

 Regards

Peter Williams
Heathcote NSW

----------
From: Andrew Pearce <arpearce@ozemail.com.au>
To: vsnet-chat@kusastro.kyoto-u.ac.jp
Cc: b.sumner@bom.gov.au; tkato@kusastro.kyoto-u.ac.jp;
varstar@voyager.co.nz
Subject: [vsnet-chat 2644] NSV4223 Pyxidis
Date: Monday, February 07, 2000 9:16

I have been observing the suspected variable NSV4223 in Pyxis over the last
40
days or so.  During this time I have detected quite a large drop in
brightness
amounting to nearly 3 magnitudes as indicated in the observations below:

JD                            Mag

2451541.2938            10.4
2451544.2813            10.4
2451547.2674            10.4
2451576.2639            11.9
2451577.2604            12.3
2451579.2674            13.0
2451580.2882            13.0
2451581.2611            13.2

The VSS of RASNZ has a chart for this star (Chart No. 1122) with letter
designation for comparison stars as a proper sequence is not available.  I
have
assigned magnitudes to these stars based on the Tycho Johnson V mags for
the
brighter stars and GSC mags for stars fainter than 11th mag.  The GSC
magnitudes
appear to be suspect with most of them appearing to be on the faint side of
what
the comparison stars actually appear.

In any case it appears that the object's variability is beyond question.  I
note
that it's spectral type is listed as SE.

I would be interested to hear if anyone else has observed this star and if
there
are any reports on the type of star it actually is.

I will keep on observing the star, and I urge others to as well, so we can
get a
better idea of it's light curve.

Regards
Andrew Pearce
Western Australia

VSNET Home Page

Return to Daisaku Nogami

---

vsnet-adm@kusastro.kyoto-u.ac.jp