Peremennye Zvezdy (Variable Stars) 34, No. 3, 2014 Received 3 October; accepted 14 November. |
Article in PDF |
A. V. Khruslov
Institute of Astronomy, Russian Academy of Sciences, Moscow, Russia; e-mail: khruslov@bk.ru
We present a new study of 28 known RR Lyrae variable stars. We analyzed all observations available for these stars in the Catalina Surveys, LINEAR, Northern Sky Variability Survey, and SuperWASP online public archives using the period-search software developed by Dr. V.P. Goranskij for Windows environment. According to these data, the stars are double-mode RR Lyrae variables, pulsating in the first-overtone and fundamental modes. |
In this article, I present the discovery of 28 more double-mode RR Lyrae variable stars, pulsating in the first-overtone and fundamental modes.
Light curves, finding charts, and data (CSS, SSS, MLS, LINEAR, NSVS, SWASP) are available online in the html version of this paper as a zip-archive. The light curves are given in the format displayed in Fig. 1. Top panels present data folded with the fundamental-mode and first overtone periods. Bottom panels show the same curves after prewhitening the other oscillation (if the frequencies and were excluded, it is also noted). These light curves are given for all data series. In three cases (No. 16, 19, 20), the data from LINEAR and Catalina surveys could not be represented with a unified system of light elements, probably indicating that both periods, and , vary.
Along with the light curves, we present power spectra of the RR Lyrae variables, for the raw data and after subtraction of the first-overtone (or fundamental mode) oscillations, as is shown in Fig. 2. The structure of the power spectra shows that the secondary periods are real.
Their period ratios, , are typical of radially pulsating double-mode RR Lyrae stars. The Petersen diagram for double-mode RR Lyrae variables of this article is displayed in Fig. 3.
Information on the studied stars is presented in Tables 1-4. Table 1 contains numbers from the GSC and USNO-B1.0 catalogs; equatorial coordinates (J2000); type and period previously known for the star, according to references from the last column, explained below the table. The tabulated coordinates of the variables were drawn from either the GSC2.3 (Lasker et al. 2008; star No. 1 in this paper) or 2MASS catalogs (Skrutskie et al. 2006).
No. | Name | Coordinates (J2000) | Type | , days | Ref |
1 | USNO-B1.0 1344-0191047 | 0744 5485 +442909 6 | RRAB | 04827138 | 1 |
2 | USNO-B1.0 1315-0208615 | 09 38 03.96 +41 33 45.2 | RRC | 0.358592 | 2 |
3 | USNO-B1.0 1338-0210776 | 09 59 38.04 +43 52 45.6 | RRAB | 0.4845666 | 1 |
4 | USNO-B1.0 1336-0219968 | 10 54 18.77 +43 40 37.8 | RRC | 0.370803 | 2 |
5 | USNO-B1.0 0738-0239220 | 11 14 36.57 -16 10 46.1 | RRC | 0.388355 | 2 |
6 | GSC 5512-01099 | 11 25 21.23 -11 16 10.3 | RRC | 0.35973 | 3 |
7 | USNO-B1.0 1349-0226600 | 11 33 51.94 +44 57 39.9 | RRC | 0.353188 | 2 |
8 | USNO-B1.0 1102-0220937 | 12 47 46.30 +20 15 48.0 | RRC | 0.384393 | 2 |
9 | USNO-B1.0 1329-0290328 | 12 50 17.77 +42 57 29.8 | RRC | 0.356830 | 2 |
10 | USNO-B1.0 0863-0260489 | 13 16 41.33 -03 36 14.6 | RRC | 0.417676 | 2 |
11 | GSC 0897-00784 | 13 19 46.77 +14 40 21.8 | RRAB | 0.460444 | 2 |
12 | USNO-B1.0 1161-0225607 | 13 56 45.27 +26 06 41.0 | RRC | 0.397025 | 2 |
13 | USNO-B1.0 1017-0252244 | 14 24 54.23 +11 47 45.2 | RRAB | 0.465064 | 2 |
14 | USNO-B1.0 1121-0267760 | 14 25 47.22 +22 10 08.6 | RRC | 0.400458 | 2 |
15 | USNO-B1.0 1226-0288064 | 14 36 49.56 +32 39 50.8 | RRAB | 0.4935225 | 1 |
16 | USNO-B1.0 1100-0231107 | 14 40 18.08 +20 01 32.0 | RRC | 0.421228 | 2 |
17 | USNO-B1.0 1295-0254008 | 14 53 55.16 +39 32 21.1 | RRC | 0.354983 | 2 |
18 | GSC 0923-00144 | 15 13 07.59 +12 08 03.6 | RRC | 0.404021 | 2 |
19 | USNO-B1.0 1265-0234869 | 15 46 19.18 +36 34 05.2 | RRC | 0.413950 | 2 |
20 | USNO-B1.0 1039-0242114 | 15 49 41.38 +13 59 35.6 | RRC | 0.444205 | 2 |
21 | USNO-B1.0 1088-0244594 | 15 54 04.37 +18 51 20.6 | RRC | 0.358311 | 2 |
22 | USNO-B1.0 1182-0267691 | 16 01 28.46 +28 15 53.4 | RRC | 0.411701 | 2 |
23 | USNO-B1.0 1023-0310699 | 16 08 25.22 +12 19 08.4 | RRC | 0.366803 | 2 |
24 | USNO-B1.0 1084-0260951 | 16 24 27.51 +18 24 49.9 | RRC | 0.417560 | 2 |
25 | USNO-B1.0 1381-0302066 | 16 39 13.41 +48 11 02.8 | RRC | 0.377389 | 2 |
26 | USNO-B1.0 0667-0901820 | 19 52 26.89 -23 17 54.3 | RRC: | 0.33662 | 4 |
27 | USNO-B1.0 0820-0768849 | 21 17 23.39 -07 59 10.9 | RRAB | 0.4679295 | 1 |
28 | USNO-B1.0 0680-1002029 | 21 17 28.18 -21 56 09.0 | RR: | - | 5 |
References in Table 1:
1. Drake et al. (2013)
2. Palaversa et al. (2013)
3. Hadon, VS-COMPAS team, 2012
( http://www.vs-compas.belastro.net/stars/by/type/RRC )
4. Otero, International Variable Star Index, 2014
5. Keller et al. (2008)
Table 2 presents identification numbers for the LINEAR database, other data used in the analysis, magnitude in the maximum and minimum in the Catalina surveys and LINEAR photometric systems.
No. | LINEAR ID | Other data | CSS magnitude | LINEAR magnitude |
1 | - | CSS | 178-188 | - |
2 | 16982312 | CSS | 16.30-17.07 | 1640-1720 |
3 | 17701631 | CSS | 16.29-17.11 | 16.38-17.18 |
4 | 23389584 | CSS | 15.26-15.77 | 15.35-15.87 |
5 | 851716 | CSS, SSS | 15.86-16.65 | 15.93-16.60 |
6 | - | CSS, SSS, NSVS | 13.32-13.98 | - |
7 | 1643135 | CSS | 16.13-16.84 | 16.22-17.17 |
8 | 4435791 | CSS | 16.29-16.86 | 16.37-16.94 |
9 | 7892817 | CSS | 15.75-16.39 | 15.82-16.49 |
10 | 8854060 | CSS, MLS | 16.59-17.26 | 16.6-17.3 |
11 | 8658610 | CSS | 13.62-14.41 | 13.75-14.54 |
12 | 10278022 | CSS | 16.18-16.76 | 16.18-16.84 |
13 | 11697185 | CSS | 15.56-16.38 | 15.71-16.46 |
14 | 11763086 | CSS | 15.74-16.35 | 15.89-16.46 |
15 | 12199470 | CSS | 15.18-15.95 | 15.33-16.03 |
16 | 12432893 | CSS | 16.13-16.74 | 16.29-16.90 |
17 | 12896695 | CSS | 15.47-16.05 | 15.63-16.39 |
18 | 13754273 | CSS | 13.69-14.28 | 13.87-14.46 |
19 | 15450888 | CSS | 15.63-16.25 | 15.81-16.35 |
20 | 15269598 | CSS | 15.96-16.61 | 16.07-16.72 |
21 | 15708768 | CSS | 15.75-16.29 | 15.67-16.39 |
22 | 16182003 | CSS | 15.04-15.62 | 15.18-15.73 |
23 | 16456815 | CSS | 15.25-15.86 | 15.45-15.98 |
24 | 18255554 | CSS | 14.67-15.23 | 14.80-15.27 |
25 | 18861334 | CSS | 15.83-16.53 | 15.93-16.68 |
26 | - | SSS, 1SWASP | 14.82-15.35 | - |
27 | - | CSS | 14.94-15.74 | - |
28 | - | CSS | 15.35-15.92 | - |
Light elements of all oscillations: the first-overtone period , the fundamental period , the first-overtone and fundamental mode epoch of maxima, period ratios , periods of the frequencies () and () are collected in Table 3.
No. | , d | , d | Epoch, JD | Epoch, JD | , d | , d | |
1 | 0.360108 | 0.482702 | 2455000.713 | 2455000.795 | 0.7460 | - | - |
2 | 0.358595 | 0.481662 | 2454500.245 | 2454500.100 | 0.7445 | 0.205560 | - |
3 | 0.360565 | 0.484580 | 2455000.700 | 2455000.535 | 0.7441 | 0.206736 | 1.4089 |
4 | 0.370794 | 0.497336 | 2455000.260 | 2455000.137 | 0.7456 | - | - |
5 | 0.388360 | 0.521023 | 2454500.080 | 2454500.500 | 0.7454 | 0.222508 | - |
6 | 0.359729 | 0.483101 | 2455000.766 | 2455000.790 | 0.7446 | - | - |
7 | 0.353195 | 0.474709 | 2454500.329 | 2454500.156 | 0.7440 | 0.202515 | 1.3798 |
8 | 0.384402 | 0.515253 | 2454500.205 | 2454500.293 | 0.7460 | 0.220153 | 1.51369 |
9 | 0.356830 | 0.479250 | 2454500.360 | 2454500.395 | 0.7446 | - | - |
10 | 0.417684 | 0.559293 | 2455000.120 | 2455000.525 | 0.7468 | - | - |
11 | 0.341883 | 0.460448 | 2454500.333 | 2454500.397 | 0.7425 | 0.1962004 | 1.3277 |
12 | 0.397031 | 0.532235 | 2454500.146 | 2454500.410 | 0.7460 | - | - |
13 | 0.345662 | 0.465042 | 2454500.220 | 2454500.354 | 0.7433 | 0.198282 | 1.34650 |
14 | 0.400452 | 0.536540 | 2454500.400 | 2454500.100 | 0.7464 | - | - |
15 | 0.367380 | 0.493517 | 2455000.602 | 2455000.795 | 0.7444 | 0.210603 | - |
16 | 0.421213 | 0.564890 | 2455000.410 | 2455000.120 | 0.7457 | 0.241131 | - |
17 | 0.354990 | 0.476987 | 2454500.125 | 2454500.326 | 0.7442 | - | - |
18 | 0.404023 | 0.541556 | 2454500.400 | 2454500.150 | 0.7460 | 0.231394 | 1.59105 |
19 | 0.413934 | 0.554870 | 2455000.075 | 2455000.135 | 0.7460 | 0.237077 | 1.62964 |
20 | 0.444237 | 0.596277 | 2455000.088 | 2455000.086 | 0.7450 | - | - |
21 | 0.358319 | 0.481733 | 2454500.260 | 2454500.385 | 0.7438 | 0.205477 | - |
22 | 0.411690 | 0.551550 |