[vsnet-sequence 15] V1494 Aquilae sequence

["Bjorn H. Granslo" <b.h.granslo@astro.uio.no>]

Bruce Sumner wrote:
> New sequences for V1494 Aql, V404 Cyg and LD 345 will be issued 
> shortly.

In order to not add confusion it should be noted that I have
prepared a sequence for Nova Aquilae 1999 No. 2 (V1494 Aquilae),
which was based on the Tycho-2 catalogue and published over a month
ago [vsnet 2018]. It contains positions, photometry (V magnitudes
and B-V colours with corresponding uncertainties), and catalogue
identifications for stars at 8th to 12th magnitude. As many may not
be aware of this sequence it is included below.

This is a very crowded field, and the comparison stars have been
carefully selected. I have only chosen stars stars that are
apparently single and not to red (B-V less than +1.0, in order to
minimize the differences between visual and Johnson V magnitudes).
I am aware that A. Henden, USNO, has provided accurate photometry
for stars at 13th magnitude and fainter.

                                  With kind regards,
                                   Bjorn H. Granslo

<><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><>

Date: Sun, 04 Jun 2000 00:39:39 +0200
From: Bjorn H. Granslo <b.h.granslo@astro.uio.no>
To: vsnet@kusastro.kyoto-u.ac.jp
Subject: [vsnet 2018] Revised and extended V1494 Aql sequence

Norwegian Astronomical Society - Variable Star Section

V1494 AQUILAE [R.A. = 19h23m05s.4, Decl. = +04o57'20" (2000.0)]

***** Revised and extended sequence of V1494 Aql (Nova 1999) *****

Id   R.A. (2000.0) Decl.   Star name       V     sV    B-V  s(B-V)
     h  m   s    o  '  "
 5  19 21 21.8 +05 07 23  TYC 0472-0641   8.39  0.02  +0.21  0.02
 6  19 23 03.3 +04 36 52  TYC 0473-5917   8.68  0.02  +0.85  0.02
 7  19 23 33.6 +05 23 14  TYC 0473-3097   8.99  0.02  +0.33  0.02
 9  19 21 54.1 +05 06 44  TYC 0472-1241   9.80  0.03  +0.51  0.04
10  19 23 07.0 +05 06 13  TYC 0473-3683  10.06  0.04  +0.25  0.04
11  19 22 43.4 +05 08 24  TYC 0473-3167  10.42  0.05  +0.75  0.07
12  19 24 04.8 +04 58 13  TYC 0473-3929  10.82  0.07  +0.30  0.07
13  19 22 27.9 +04 49 42  TYC 0472-1442  11.29  0.11  +0.31  0.11
14  19 23 42.2 +04 42 46  TYC 0473-1284  11.9   0.2   +0.2   0.2
15  19 23 40.0 +05 06 53  TYC 0473-4553  12.5   0.3   +0.2   0.3

Positions and star names are from Tycho-2 catalogue (Hog et al.
2000), obtained via the VizieR Service at Centre de Donn馥s
astronomiques de Strasbourg. Star identifications (numbers 5-15)
are due to NAS.VSS. V magnitudes and B-V colours are calculated
from Tycho-2 BT and VT magnitudes. The following transformation
formulae have been used:

V = VT - 0.090 * (BT - VT) = 1.090 * VT - 0.090 * BT
B-V = 0.850 * (BT - VT)

The uncertainties in V and B-V, sV and s(B-V), are calculated from
corresponding uncertaintes in BT and VT, sBT and sVT, using the
following relations:

sV = [(1.090 * sVT)^2 + (0.090 * sBT)^2]^0.5
s(B-V) = 0.850 * [(sBT^2 + sVT^2)]^0.5

It should be noted that magnitudes and colours are uncertain for
the fainter stars (especially stars 14 and 15). V and B-V data for
these stars should not be relied upon (see e.g. the comments by
B. Skiff in vsnet-chat 2964). More accurate measurements are
necessary for these stars.

Comparison stars have been selected with care. This sequence only
contains stars that are apparently single and not to red
(B-V < 1.0).

                                   Yours sincerely,
                                   Bjorn H. Granslo
                                  [Director, NAS.VSS]

VSNET Home Page

---

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