From jop at astro.columbia.edu  Mon Apr  7 13:49:05 2014
From: jop at astro.columbia.edu (Joe Patterson)
Date: Mon, 07 Apr 2014 13:49:05 -0400
Subject: (cba:news) IR Com, EX Hya, DW UMa, AY Sex, V1159 Ori
Message-ID: <5342E511.8040708@astro.columbia.edu>

Dear CBAers,

Time for a status report on some of our stars.

1. V1159 Ori.  We're finished with it for the year.

2. EX Hya.  Likewise, Nice tune-up of the ephemerides.

3. AY Sex.  Could you resume regular monitoring - to measure the 
magnitude, and also, if you can get good data, any variability 
(flickering?).  We have an HST observation later in April.

4. DW UMa.  Great result, as Enrique advertised!  Simultaneous positive 
and negative superhumps, with the eclipse shape varying as a function 
of... well, precession phase, but since there are presumably TWO types 
of precession, we need to distinguish sharply between the two.  This 
merits a couple more weeks of data, especially by us norteamericanos 
(the Spaniards are going great guns on it).

5. IR Com.  As some of you know, the credentials of this alleged dwarf 
nova are somewhat in doubt, because it hardly ever erupts.  It would be 
a lot more pleasant if the star were magnetic - either an AM Her or DQ 
Her star.  So... #1, get occasional snapshots of the star to see its 
luminosity state (and warning, it has deep eclipses)... and #2, if you 
have good signal-to-noise at 17.0, get some time series to test for a 
fast periodic signal.

More later.

joe
____________________________________________________________
Center for Backyard Astrophysics (CBA) mailing lists
https://cbastro.org/communications/mailing-lists/ 



From jop at astro.columbia.edu  Thu Apr 17 05:50:34 2014
From: jop at astro.columbia.edu (Joe Patterson)
Date: Thu, 17 Apr 2014 05:50:34 -0400
Subject: (cba:news) Fwd: (cba:chat) PNV and MASTER
In-Reply-To: <13B24C3B-A955-4453-A885-1CEDA7C56B00@gmail.com>
References: <13B24C3B-A955-4453-A885-1CEDA7C56B00@gmail.com>
Message-ID: <534FA3EA.4020305@astro.columbia.edu>

I just wanted to add some emphasis to Enrique's note.  Definitely time 
for los norteamericanos to come to the rescue re MASTER J1759+25!
PNV J1714 might be a challenge up north, but we have traditional 
strength in South Africa, New Zealand, and Australia.  These appear to 
be quite unusual dwarf novae, and plenty bright.

joe p


joe


-------- Original Message --------
  Wed, 16 Apr 2014 17:25:47 -0700 (PDT)
From: Enrique de Miguel <edmiguel63 at gmail.com>
Date: Thu, 17 Apr 2014 02:25:45 +0200


We have two new fresh WZ-Sge candidates out there.

PNV J17144255-2943481 on JD 763 (Josh) shows clear early superhumps. 
This is a good target for the second half of the evening
for southerners, and some runs other than those from Josch=Chile would 
help. It's quite bright at 10.9 (JD 763)

  Also, MASTER OT J175924.12+252031.7 has been showing early superhumps 
for the last 5-6 days, but all runs we have
so far are from European longitudes and data from distant sites are 
needed for clearing up the alias frequencies. This one should
be now at around 14.3-14.4.

Enrique
____________________________________________________________
Center for Backyard Astrophysics (CBA) mailing lists
https://cbastro.org/communications/mailing-lists/



____________________________________________________________
Center for Backyard Astrophysics (CBA) mailing lists
https://cbastro.org/communications/mailing-lists/ 



From jop at astro.columbia.edu  Thu Apr 24 15:34:49 2014
From: jop at astro.columbia.edu (Joe Patterson)
Date: Thu, 24 Apr 2014 15:34:49 -0400
Subject: (cba:news) all AY Sex, all the time
Message-ID: <53596759.9030809@astro.columbia.edu>

Dear CBAers,

Starting now and going for about a week, make an all-out effort to 
obtain time series of AY Sex = PSR J1023+0038.  Here are some recent 
light curves, from MDM Observatory, which give you an idea of what you 
might see.  The coords are 10 23 47.687 +00 48 41.1.  Nominal brightness 
is 17.3, but it varies in a pattern which is not yet known.  The first 
of the "missing link" millisecond pulsars.

We have a Hubble Space Telescope observation coming up this week.  I'll 
write with the exact time, but we need to get absolutely the maximum 
density of observation during the week, starting right away. Follow it 
to large airmass, and if possible include the airmass in the report 
(I'll correct for it).  Since it's equatorial, everyone can observe it, 
and my hope is that we can stitch together a nice one-week light curve 
despite the slightly unfavorable RA (short-ish runs from everybody).

The star GSC 0246-0153 could be a good comparison - but I'll be happy 
for observations with any comp star.  Ours is part of a worldwide 
campaign to observe it at all possible wavelengths during this week 
(radio through X-ray, and especially UV where the HST will observe it).

I'll write tomorrow re other targets. but very good morning targets 
would be NR TrA (south), HS1813+61 (north), and HP Lib (both).  That's 
leaving out the dwarf novae, which I'll leave to Enrique to comment on.

joe p
-------------- next part --------------
A non-text attachment was scrubbed...
Name: psrj1023.pdf
Type: application/pdf
Size: 412357 bytes
Desc: not available
URL: <http://cbastro.org/pipermail/cba-public/attachments/20140424/7b90aa6b/attachment.pdf>
-------------- next part --------------
____________________________________________________________
Center for Backyard Astrophysics (CBA) mailing lists
https://cbastro.org/communications/mailing-lists/ 

From jop at astro.columbia.edu  Thu Apr 24 16:31:22 2014
From: jop at astro.columbia.edu (Joe Patterson)
Date: Thu, 24 Apr 2014 16:31:22 -0400
Subject: (cba:news) more on AY Sex
Message-ID: <5359749A.6040907@astro.columbia.edu>

BTW I sent incorrect coordinates.  38, not 48!  So the correct 
coordinates are 10 23 47.687 +00 38 41.15.  Whew.

Best to observe unfiltered, since it's the activity level we want to 
study (and compare with other wavelengths).  But a few integrations in V 
light would also be good, to establish the star's calibrated V 
magnitude.  Usually a good general rule, by the way.

 From the light curves I sent, note there seems to be a pattern of a 
slow sinusoidal wave - perhaps the result of the heated secondary - plus 
"positive flickering" (only upward excursions from the 4.8 hour orbital 
wave).  The latter is alleged to be from the rapidly spinning neutron 
star.  Let's see if this explanation holds up.

When you know the approximate V brightness, send it in!  HST, or a gang 
of humans running it, is always nervous about these active binaries 
frying their detector.

joe p
____________________________________________________________
Center for Backyard Astrophysics (CBA) mailing lists
https://cbastro.org/communications/mailing-lists/ 



From jop at astro.columbia.edu  Sat Apr 26 08:10:34 2014
From: jop at astro.columbia.edu (Joe Patterson)
Date: Sat, 26 Apr 2014 08:10:34 -0400
Subject: (cba:news) AY Sex precise scheduling
Message-ID: <535BA23A.1070706@astro.columbia.edu>

Dear CBAers,

The HST observation of AY Sex appears to be set for 14 hours "tonight" - 
starting from 5:03 UT April 27.  Seemingly good for the Americas and the 
Pacific (including NZ/AU), probably not as good for Europe.  It would 
certainly be great to get strictly simultaneous ground-based time-series 
photometry!  But the several days before and after will also trace out 
the full story of the variability.  Also, these times are a few days 
old, and might get bumped... so it's time for all longitudes and 
latitudes to get to battle stations!

joe
____________________________________________________________
Center for Backyard Astrophysics (CBA) mailing lists
https://cbastro.org/communications/mailing-lists/