Peremennye Zvezdy

"Peremennye Zvezdy",
Prilozhenie
,
vol. 11, N 30 (2011)

Six High-Amplitude Double-Mode Delta Scuti Variables

A. V. Khruslov
Tula, Russia

Received:   5.05.2011;   accepted:   28.10.2011
(E-mail for contact: khruslov@bk.ru)


#NameOtherCoord (J2000)TypeMaxMinSystemPeriodEpoch (JD)typeSpCommentL.CurveFind.ChartData
1 TYC 0075 01143 104 26 05.90, +01 26 26.2DSCT(B)12.212.75V(see Comments)(see Comments)max Comm. 11.PNG ASAS 042606+0126.4 NSVS 12210319
2 GSC 6009-0008908 18 06.98, -22 14 07.7DSCT(B)12.0512.8V(see Comments)(see Comments)max Comm. 22.PNG ASAS 081807-2214.1
3 TYC 8177 00131 1, HD 7790609 03 13.34, -52 02 28.7DSCT(B)9.609.95V(see Comments)(see Comments)maxA9VComm. 33.PNG ASAS 090313-5202.5
4 TYC 7909 00809 118 25 36.26, -42 13 35.8DSCT(B)11.4312.0V(see Comments)(see Comments)max Comm. 44.PNG ASAS 182536-4213.6
5 TYC 8769 01343 119 22 27.39, -56 22 28.1DSCT(B)11.6412.08V(see Comments)(see Comments)max Comm. 55.PNG ASAS 192227-5622.5
6 TYC 1103 01012 1, BD+08 458320 58 49.64, +08 54 05.3DSCT(B)10.2110.51V(see Comments)(see Comments)maxF0Comm. 66.PNG ASAS 205850+0854.1 NSVS 11548864 NSVS 14320267

Comments:


1. Type EC/DSCT (contact binary or Delta Scuti star) with the period of 0.07443 days in the ASAS-3 catalog. Actually it is a DSCT(B) star.

ModeFrequency, c/d Semi-amplitude V, mag Period, days Epoch, JD
f0 13.43542 0.126 0.0744301 2453600.043
f1 17.27023 0.062 0.0579031 2453600.049

The period ratio of the first overtone and fundamental modes is P1/P0 = 0.7780. B–V = 0.320 (Tycho2), J–H = 0.204 (2MASS). ROTSE-I/NSVS data gives similar results.


2. Type DSCT with the period of 0.228712 days in the ASAS-3 catalog. Actually it is a DSCT(B) star.

ModeFrequency, c/d Semi-amplitude V, mag Period, days Epoch, JD
f0 4.372259 0.213 0.2287147 2453600.173
f1 5.739401 0.071 0.1742342 2453600.055
f1 + f0 10.11165 0.039 0.0988958 2453600.097
f1 - f0 1.36715 0.029 0.73145 2453600.390
f1 + 2f0 14.48392 0.023 0.0690421 2453600.056

The period ratio of the first overtone and fundamental modes is P1/P0 = 0.7618 . J–H = 0.184 (2MASS).


3. Type DSCT with the period of 0.077459 days in the ASAS-3 catalog. Actually it is a DSCT(B) star.

ModeFrequency, c/d Semi-amplitude V, mag Period, days Epoch, JD
f1 12.91006 0.128 0.0774590 2453600.046
f2 16.01309 0.017 0.0624489 2453600.022
f2 + f1 28.92313 0.008 0.0345744 2453600.038

The period ratio of the second and first overtone modes is P2/P1 = 0.8062 . B–V = 0.414 (Tycho2), J–H = 0.127 (2MASS).


4. Type DSCT with the period of 0.107193 days in the ASAS-3 catalog. Actually it is a DSCT(B) star.

ModeFrequency, c/d Semi-amplitude V, mag Period, days Epoch, JD
f0 9.328933 0.180 0.1071934 2453600.038
f1 12.171210 0.051 0.0821611 2453600.018
f1 + f0 21.50015 0.025 0.0465113 2453600.024
f1 - f0 2.842290 0.013 0.351829 2453600.300

The period ratio of the first overtone and fundamental modes is P1/P0 = 0.7665. B–V = 0.417 (Tycho2), J–H = 0.172 (2MASS).


5. Type DSCT with the period of 0.149089 days in the ASAS-3 catalog. Actually it is a DSCT(B) star.

ModeFrequency, c/d Semi-amplitude V, mag Period, days Epoch, JD
f0 6.707367 0.091 0.1490898 2453600.025
f1 8.867599 0.066 0.1127701 2453600.011
f1 + f0 15.57492 0.021 0.0642058 2453600.013

The period ratio of the first overtone and fundamental modes is P1/P0 = 0.7564. B–V = 0.402 (Tycho2), J–H = 0.148 (2MASS).


6. Type DSCT with the period of 0.176448 days in the ASAS-3 catalog. Actually it is a DSCT(B) star.

ModeFrequency, c/d Semi-amplitude V, mag Period, days Epoch, HJD
f1 5.66738 0.071 0.1764484 2453745.115
f2 7.10332 0.055 0.1407792 2453745.077
f1+f2 12.77076 0.010 0.0783039 2453745.012

The period ratio of the second and first overtone modes is P2/P1 = 0.7978. B–V = 0.399 (Tycho2), J–H = 0.149 (2MASS). The ROTSE-I/NSVS data (Wozniak et al. 2004) with photometric correction flags (usually rejected) were kept for the analysis.

Remarks:
I present an investigation of six 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



Main Page | Search
Astronet | SAI | INASAN

Report problems