Comments:
1.     TYC 0658
00556
1 =
ASAS 035407+0759.2 =
NSVS 9387852 = NSVS 12150953
B-V = 0.355 (Tycho2), J-H = 0.144 (2MASS), P1/P0 = 0.7682
P = 0.13979 d (Pojmanski 2002)
Mode |
Frequency, c/d |
Semi-amplitude, V mag |
Period, day |
Epoch, HJD |
f0 |
7.15352 |
0.074 |
0.1397914 |
2453724.066 |
f1 |
9.31170 |
0.081 |
0.1073918 |
2453724.108 |
2.     GSC 8959-00409 =
ASAS
110953-6058.0
J-H = 0.156 (2MASS), P1/P0 = 0.7748
P = 0.110801 d (Pojmanski 2002)
Mode |
Frequency, c/d |
Semi-amplitude, V mag |
Period, day |
Epoch, HJD |
f0 |
9.02516 |
0.160 |
0.1108014 |
2453681.038 |
f1 |
11.64806 |
0.06 |
0.0858512 |
2453681.103 |
f1 + f0 |
20.67337 |
0.03 |
0.0483714 |
2453681.022 |
3.     TYC 8664 00911 1
=
ASAS 135715-5255.4 = HD 121517
B-V = 0.460 (Tycho2), J-H = 0.170 (2MASS), P1/P0 = 0.7712
P = 0.11103 d (Pojmanski 2002)
Mode |
Frequency, c/d |
Semi-amplitude, V mag |
Period, day |
Epoch, HJD |
f0 |
8.49018 |
0.065 |
0.1177831 |
2453490.086 |
f1 |
11.00931 |
0.112 |
0.0908322 |
2453490.091 |
f1 + f0 |
19.49949 |
0.026 |
0.0512834 |
2453490.036 |
f1 - f0 |
2.51913 |
0.020 |
0.396962 |
2453490.123 |
2f1 - f0 |
13.52843 |
0.007 |
0.0739184 |
2453490.024 |
2f0 |
16.98035 |
0.01 |
0.0588916 |
2453490.024 |
3f0 |
25.47057 |
0.01 |
0.0392610 |
2453490.005 |
4.     TYC 7355 00453 1
=
ASAS 162022-3541.2 = HD 146953
B-V = 0.657 (Tycho2), J-H = 0.227 (2MASS), P2/P1 = 0.7978
P = 0.1843 d (Pojmanski 2002)
Mode |
Frequency, c/d |
Semi-amplitude, V mag |
Period, day |
Epoch, HJD |
f1 |
5.42593 |
0.072 |
0.1843001 |
2453095.082 |
f2 |
6.80065 |
0.039 |
0.1470447 |
2453095.159 |
f2 + f1 |
12.22664 |
0.008 |
0.0817886 |
2453095.040 |
2f2 |
13.60113 |
0.016 |
0.0735224 |
2453095.050 |
Remarks:
I present an investigation of four known DSCT variables. The variability of these
stars was
reported by Pojmanski (2002).
I re-analysed ASAS-3 and NSVS data using the period-search software developed
by Dr. V.P. Goranskij for Windows environment. According to ASAS-3 (Pojmanski 2002)
and
ROTSE-I/NSVS (Wozniak et al. 2004) data, the variables are high-amplitude double-mode
Delta
Scuti stars.
The period ratios P1/P0 and P2/P1 are typical for radially pulsating high-amplitude
double-mode
Delta Scuti stars (Petersen & Christensen-Dalsgaard 1996).
In certain cases, multiple frequencies or frequencies connected with interactions
between the two main modes were found (see the Comments).
References:
Petersen, J.O., Christensen-Dalsgaard, J., 1996, Astron. and Astrophys., 312, 463
Pojmanski, G., 2002, Acta Astronomica, 52, 397
Wozniak, P.R., Vestrand, W.T., Akerlof, C.W., et al., 2004, Astron. J.,
127, 2436