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Revista mexicana de astronomía y astrofísica

versión impresa ISSN 0185-1101

Rev. mex. astron. astrofis vol.57 no.1 Ciudad de México abr. 2021  Epub 30-Sep-2021

https://doi.org/10.22201/ia.01851101p.2021.57.01.18 

Articles

Results of Observations of Maxima of Pulsating Stars1

J. H. Peña2  3  4 

H. Huepa2 

D. S. Piña3  4 

J. Guillén4 

A. Rentería2 

J. D. Paredes5 

R. Muñoz6 

J. Donaire6 

T. Benadalid6 

2Observatorio Astronómico Nacional de Tonantzintla, Universidad Nacional Autónoma de México, México.

3Instituto de Astronomía, Universidad Nacional Autónoma de México, México.

4Facultad de Ciencias, Universidad Nacional Autónoma de México, México.

5Facultad de Ciencias, Universidad Central de Venezuela, Venezuela.

6Planetario Max Schreier, Universidad Mayor de San Andrés, Bolivia.


ABSTRACT

The systematic study of some HADS stars, recognized as variables for decades, has allowed us to provide data on their secular variations through O-C analysis. However, some of the data have large gaps without observations. This is our motivation for continuously observing these stars as part of the research carried out by the \Grupo de Astronomía Observacional del Observatorio de Tonantzintla" (GAOOT). This article is our third compilation of times of maxima for pulsating stars. These observations have been carried out at the Observatorio Astronómico Nacional de Tonantzintla (TNT) and San Pedro Mártir (SPM), México and for the first time we also present data from the Complejo Astron_omico de Cota Cota, Bolivia (Universidad Mayor de San Andrés) and the Observatorio Astronómico Centroamericano de Suyapa, Honduras (Universidad Nacional Autónoma de Honduras).

Key Words ephemerides; stars; variables: Scuti

RESUMEN

El estudio sistemático de algunas estrellas pulsantes HADS ha permitido proporcionar datos sobre sus variaciones seculares mediante el análisis O-C. Sin embargo, en algunas de ellas los datos presentan grandes vacíos temporales sin observaciones. Esta es una motivación por la que hemos decidido observar continuamente estas estrellas como parte del trabajo que realiza el Grupo de Astronomía Observacional del Observatorio de Tonantzintla. Este grupo presenta esta tercera compilación de tiempos de máximo de estrellas pulsantes. Dichas observaciones se han llevado a cabo en los Observatorios Astronómicos Nacionales de Tonantzintla (TNT) y San Pedro Mártir (SPM), México a los que se han unido el Complejo Astronómico de Cota Cota, Bolivia (Universidad Mayor de San Andrés, Bolivia) y el Observatorio Astronómico Centroamericano de Suyapa Universidad Nacional Autónoma de Honduras).

1.Motivation

The study of δ Scuti stars has been carried out for many years since the pioneering works of Breger (1966) and Millis (1966). It was shortly after this that the monitoring of some of these stars was started in Mexico (Warman, Malacara and Breger, 1974, Warman, Peña and Arellano Ferro, 1979) and it has continued ever since.

More recently, with the acquisition of CCD detectors thirteen years ago, the observations of 𝛿 Scuti stars were retaken at the Observatorio Astronomico Nacional de Tonantzintla (TNT) with the participation of many students of the Observational Astronomy courses taught at the UNAM and later of the Escuela Latinoamericana de Astronomía Observacional (ESAOBELA). These students have provided us with motivation, and have supplied an eager workforce.

HADS stars provided excellent targets since they have short periods of pulsation, large amplitudes and, most of them have been observed for large time spans providing a unique chance to study their secular variations. Surprisingly, most of the observed stars we studied show evidence of a light travel-time effect, suggesting the presence of another invisible companion star.

What we have found is that some of these stars have lacked continuous observations and that there are large gaps in which they were not observed. Conscious of the need for long continuous observations, we developed a systematic monitoring of HADS stars at Tonantzintla to pursue our study of HADS double systems.

Aware of this need we have previously presented two lists of times of maxima of pulsating stars (Peña et al. 2015 and Peña et al. 2017) and here we present the third list of results from our observations.

2.Data collection

This is the third compilation of OAN results of 23 variable stars obtained from 2016 to March, 2020. These observations also include some maxima from the Observatorio Astronómico Centroamericano de Suyapa, Honduras and the Complejo Astronómico de Cota Cota, Bolivia. The results are presented for 23 stars, of which 114 maxima of pulsating stars were obtained.

The CCD reduction was done with AstroImageJ (Collins et al. 2017) whereas the photoelectric observations were reduced using a classical procedure (see Peña et al., 2016 for details). All times of maxima are heliocentric and were determined with a fifth grade polynomial fitting to the light curve.

The errors were determined from the RMS error of the residuals evaluated for the times of maxima, and are about 0.016 days. The accuracy of each point is given by the exposure time and varies between 3 min for the 1-meter telescope and 1 min for the smaller telescopes. It may seem contradictory to use a longer integration time for the larger aperture telescope. However, this is done because the mounting of the smaller telescopes is of an altazimuth type, which does not allow long integration times. For the 1-meter telescope there were around 40,000 counts, and for the 10-inch telescope there were 11,000 counts, enough to secure the high precision desired. The photoelectric measurements and all the light curves can be requested for inspection. The procedure followed to reduce uvby-β of the San Pedro Martir Observatory is presented in Peña et al. (2021).

In Table 1 we present the characteristics of the observed stars; that is, their IDs, coordinates (epoch 20009), V magnitude, spectral types and the observational epoch and periods in days when available from the web site of the General Catalog of Variable Stars (http://www.sai.msu.su/gcvs/cgi-bin/search.htm GCVS) as they are reported in that source. No errors are provided. All information about telescopes, photometers and filters is specified in the remarks of the table. In Table 2 the following quantities are listed: Column 1 is the ID, Column 2, date of observation, Column 3, N gives the number of data points in each run, Column 4, 𝛥t is the time span in days of the run, Column 5, the number of Tmax of the run, Column 6, the time of maxima in HJD, Column 7, the telescope, Column 8, the filter used, Column 9, the detector, Column 10 the observatory, and finally, Column 11 gives the observers and reducers. Observers and reducers are specified in the remarks at the end of the table.

TABLE 1 CHARACTERISTICS OF THE OBSERVED STARS 

ID RA Dec Magnitude Spectral Type Epoch (d) P (d)
AD Ari 02 17 45 +18 27 18.00 7.43 F0 2453330.654 0.53972
RV Ari 02 15 07 +18 04 27.91 11.61 A0 0.09312808
BE Lyn 09 18 17 +46 09 11.31 8.80 A3
BL Cam 03 47 19 +63 22 42.14 13.03 0.03909844
V367 Cam 04 40 55 +53 38 06.46 10.47 0.121596
KU Cen 11 51 51 -41 17 09.23 13.48 0.07996
AD Cmi 07 52 47 +01 35 50.47 9.38 F0IV/V 2453478.4714 0.1229746
AZ Cmi 07 44 07 +02 24 19.52 6.47 A5IV 0.095205
VZ Cnc 08 40 52 +09 49 27.15 7.18 A9III 0.178364
KZ Hya 10 50 54 -25 21 14.72 10.06 B9III/IV 2442516.15836 0.0595104212
AN Lyn 09 14 28 +42 46 38.36 10.64 A7IV/V
BO Lyn 08 43 01 +40 59 51.77 11.49
SZ Lyn 08 09 35 +44 28 17.61 9.08 F2 2438124.39824 0.120534920
TV Lyn 07 33 31 +47 48 09.83 11.54 A6 2440950.922 0.24065119
1 Mon 05 59 01 -09 22 56.00 6.16 F2/3IV 2441661.1668 0.13612600
V1162 Ori 05 32 01 -07 15 24.65 9.9
RR Leo 10 07 43 +23 59 30.32 9.94 F0 2443295.402 0.4523933
V369 Sct 18 51 16 -06 21 11.16 9.35 F3/5II 2440393.709 0.223
AE Uma 09 36 53 +44 04 00.40 11.35 A9 2435604.338 0.086017055
EX Uma 08 45 12 +56 36 26.76 11.02
GW Uma 10 44 11 +44 40 44.11 9.89 F3V
YZ Boo 15 24 06 +36 52 00.60 10.36 F0 2448500.0030 0.1040920
EH Lib 14 58 55 -00 56 53.01 9.83 A5 2433438.6082 0.0884132445

TABLE 2 TIMES OF MAXIMUM LIGHT OF THE VARIABLE STARS CONSIDERED 

ID Date N ∆t(d) Nmax Tmax +2450000 Telescope Filters Detector Observatory Observers/ Reducers
AD Ari 19120607 368 0.2119 1 8824.6543 Me V 1001 TNT JGT,HHC/JGT
RV Ari 19112930 81 0.1294 1 8817.7421 Me V 1001 TNT FS,DSP/DSP
19113031 113 0.1841 2 8818.7621 Me V 1001 TNT FS,DSP/DSP
19113031 8818.8606
BE Lyn 17032223 420 0.1173 1 7835.6745 M8 G 402 OACS AA/ARL,GIEP
BL Cam 20011112 122 0.0960 3 8860.7052 M2 wo andor TNT E20/HHC
8860.7448
8860.7842
20011213 162 0.1396 3 8861.7247 M2 wo andor TNT E20/HHC
8861.7641
8861.8022
20011314 116 0.0880 3 8862.7415 M2 wo andor TNT E20/HHC
8862.7804
8862.8204
20011415 151 0.1230 3 8863.7182 M2 wo andor TNT E20/HHC
8863.7599
8863.7959
20011617 117 0.0906 2 8865.7510 M2 wo andor TNT E20/HHC
8865.7905
20011718 146 0.1187 2 8866.7287 M2 wo andor TNT E20/HHC
8866.7684
20022425 40 0.0819 2 8904.6927 84 uvby − β danish SPM DSP/DSP
8904.7318
V367 Cam 20011314 91 0.1442 1 8862.8298 M1 V ST-8300 TNT E20/JGT
KU Cen 20011213 97 0.0818 1 8861.9195 M2 wo andor TNT E20/HHC
20011314 100 0.0724 1 8862.8795 M2 wo andor TNT E20/HHC
20011415 120 0.0934 1 8863.9195 M2 wo andor TNT E20/HHC
20011617 137 0.1232 2 8865.9165 M2 wo andor TNT E20/HHC
8865.9965
AD CMi 16021112 130 0.1400 1 7430.7541 M2 V 1001 TNT DSP/DSP
16031112 167 0.1500 1 7459.6543 M1 V 1001 TNT AOA16/DSP
17011415 144 0.1200 1 7768.8131 M1 V 1001 TNT E17/DSP
17120607 40 0.1000 1 8095.0522 84 uvby − β danish SPM JCC,DSP/DSP
18030203 142 0.1600 1 8180.7831 M1 V 1001 TNT AOA18/DSP
18030304 157 0.1500 1 8181.7596 M1 V 1001 TNT AOA18/DSP
18031718 129 0.1300 1 8195.7759 M1 V 1001 TNT AOA18/DSP
19011415 84 0.1500 1 8498.8915 M2 G ST-800 TNT E19/HHC
19011516 97 0.1500 1 8499.8951 M2 G ST-800 TNT E19/HHC
19011819 205 0.1600 1 8502.8419 M2 G ST-800 TNT E19/HHC
19012122 141 0.1900 1 8505.9170 M2 G ST-800 TNT E19/HHC
19012223 186 0.2100 2 8506.7780 M2 G ST-800 TNT E19/HHC
8506.9044
19020102 228 0.2700 2 8516.7387 M2 wo ST-8300 TNT JGT/JGT
8516.8638
19031617 187 0.1400 1 8559.7805 Me V 1001 TNT AOA19/ARL
AZ CMi 20021920 51 0.1151 1 8899.8223 84 uvby − β danish SPM DSP/DSP
VZ Cnc 18031718 267 0.2107 1 8195.7696 M1 G ST-800 TNT JGT,HHC/JGT
19012122 211 0.1873 1 8505.9443 M1 G ST-800 TNT E19/JGT
19012223 372 0.2447 1 8506.8515 M1 G ST-800 TNT E19/JGT
19121011 383 0.1198 1 8828.9646 Me V ST-8300 TNT JGT/JGT
20022526 36 0.2352 1 8905.8573 84 uvby − β danish SPM DSP/DSP
20022627 49 0.0969 1 8906.9136 84 uvby − β danish SPM DSP/DSP
20032829 150 0.1304 1 8937.7654 M1 V ST-8300 TNT JGT/JGT
KZ Hya 17032223 270 0.7285 1 7835.7613 M8 G 402 OACS AA/ARL,GIEP
18021617 87 0.0919 2 8166.7547 Me V 1001 TNT SBJ,ALZ/HHC
8166.8144
19020102 6 0.0678 1 8516.9686 M2 G ST-800 TNT Bo19/JGT
19030102 50 0.0409 1 8544.8786 M1 V 1001 TNT AOA19/HHC
19040506 1393 0.2109 3 8579.6324 M8 G 402 OACS Ho19/ARL,GIEP
8579.6918
8579.7512
19042021 110 0.0930 2 8594.6884 Me V 1001 TNT DSP/DSP
8594.7480
20012021 87 0.0892 1 8869.9210 Me V 1001 TNT E20/DSP,HHC
20031314 64 0.0565 1 8922.8845 Me V 1001 TNT AOA20/HHC
20031314 40 0.0309 1 8922.8847 M1 V ST-8300 TNT AOA20,JGT/HHC,JGT
AN Lyn 20010910 394 0.0966 1 8859.9659 M2 wo andor TNT E20/HHC
BO Lyn 19011516 176 0.1419 2 8499.7999 Me V 1001 TNT E18/JGT
8499.8890
SZ Lyn 18011213 90 0.0702 1 8131.8979 M1 V ST-8300 TNT E18/HHC
18011516 165 0.1672 1 8134.9104 M1 V ST-8300 TNT E18/HHC
18011617 176 0.0873 2 8135.7517 M1 V ST-8300 TNT E18/HHC
8135.8755
18012021 121 0.1053 1 8139.8537 M1 V ST-8300 TNT E18/HHC
19020203 115 0.1106 1 8517.8584 M2 G ST-800 TNT Bo19/JGT
TV Lyn 19011617 300 0.0208 1 8135.8526 M2 G ST-800 TNT E18/HHC
19020405 304 0.2884 1 8519.7864 M2 G ST-800 TNT Bo19/JGT
19020708 190 0.2903 1 8522.7723 M2 G ST-800 TNT Bo19/JGT
1 Mon 19020506 187 0.1481 1 8520.7220 M2 G ST-800 TNT Bo19/JGT
V1162 Ori 20011213 151 0.1118 1 8861.8051 Me V 1001 TNT E20/DSP
20011718 185 0.1533 2 8866.7603 Me V 1001 TNT E20/DSP
8866.8368
20022324 41 0.0940 1 8903.7422 84 uvby − β danish SPM DSP/DSP
RR Leo 19011314 90 0.0881 1 8497.8039 Me V 1001 TNT Bo19/DSP
19012122 260 0.2516 1 8505.9479 Me V 1001 TNT Bo19/DSP
19012223 310 0.2804 1 8506.8542 Me V 1001 TNT Bo19/DSP
19013101 390 0.3257 1 8515.9003 Me V 1001 TNT Bo19/DSP
19020102 390 0.3589 1 8516.8054 Me V 1001 TNT Bo19/DSP
19020203 363 0.3211 1 8517.7120 Me V 1001 TNT Bo19/DSP
20022425 72 0.1883 1 8904.9676 84 uvby − β danish SMP DSP/DSP
20022526 36 0.2635 1 8905.8787 84 uvby − β danish SPM DSP/DSP
20033031 375 0.3155 1 8939.8071 M1 V ST-8300 TNT JGT/JGT
V369 Sct 19082930 471 0.1785 1 8817.7421 C16 v 1001 CotaCota JMD/DSP
AE Uma 18011617 162 0.0545 2 8135.8224 Me V 1001 TNT E18
8135.9041 Me V 1001 TNT
18021617 90 0.0746 1 8166.8715 Me V 1001 TNT SBJ,ALZ/HHC
18032526 100 0.0842 1 8203.8565 M1 G ST-800 TNT JGT/JGT
19011415 69 0.1120 1 8498.8116 Me V 1001 TNT E19/JGT,DSP
19020304 273 0.1925 2 8518.7688 Me V 1001 TNT Bo19/JGT
8518.8482
EX Uma 20011617 135 0.2232 1 8865.9608 M1 G ST-8300 TNT E20/JGT
GW Uma 19020102 218 0.1738 1 8516.9623 M1 V 1001 TNT Bo19/JGT
19020203 267 0.2392 1 8517.7795 M1 V 1001 TNT Bo19/JGT
19022122 220 0.1721 1 8536.8787 M1 G ST-800 TNT JGT
19022324 124 0.1085 1 8538.9137 1M V ST-8300 TNT JGT,APC/JGT
20011415 101 0.1310 1 8864.0182 M1 G ST-8300 TNT E20/JGT
YZ Boo 18032829 120 0.1123 1 8206.8536 M1 G ST-800 TNT JGT,DSP/JGT
18030304 90 0.0800 1 8181.8708 me V 1001 TNT AOA18/HHC
18031617 76 0.8148 1 8194.8829 me V 1001 TNT AOA18/HHC
19042021 130 0.1172 1 8594.8027 Me V 1001 TNT DSP/DSP
20021920 30 0.0653 1 8899.9954 84 uvby − β danish SPM DSP/DSP
20022324 68 0.1622 2 8903.8477 84 uvby − β danish SPM DSP/DSP
EH Lib 18031718 129 0.1114 2 8195.8240 me V 1001 TNT AOA18/HH
8195.9122

Remarks:
1. Telescope 2. Detector 3. Filter
1M - 1m telescope ST8 - CCD SBIG ST-8 V - V-filter in UBV system
ME - 10” Meade LX200 telescope Equatorial
M1 - 10” Meade LX200 telescope 1001 - CCD SBIG ST-1001 G - Green in RGB set
M2 - 10” Meade LX200 telescope 8300 - CCD SBIG ST-8300 V - y-filter in uvby system
C11 - 11” Celestron telescope danish - uvby-β Photometer wo - Without filter
84 - 0.84m telescope 402 - CCD SBIG ST-402
C16 - 16” Celestron Pacific telescope
M8 - Meade LX200 telescope

Remarks (Continued). Observers.: AA: A. Artola (UNAH); ALZ: A. L. Zuñiga; ARL: A. Rentería; DSP: D. S. Piña; FS: F. Saldaña; JCC: J. Calderón; JGT: J. Guillen; JHP: J. H. Peñaa; SBJ: S. B. Ju_arez.

E17 (ESAOBELA 2017): Ramirez, Vanesa; Rodríguez, Mariana; Vargas, Stephany; Castellón, Cindy; Salgado, Ricardo; Mata, Joaquin; Santa Cruz, Raúl; Chipana, Karol; Gonzales, Lisseth; Rodríguez, Reina; De la Fuente, Diana.

E18 (ESAOBELA 2018): Calle, Carla; Huanca, Ever; Uchima, Juan Pablo; Ramírez, Raquel; Funes, Ricardo; Martinez, Juan José; Sarmiento, Karina; Cruz, Mauricio; Meza, Enith; Alvarado, Mayubell; Huaman, Victor; Ochoa, Gerson; Matamoros, Andrea.

E19 (ESAOBELA 2019): Blanco, Agustina; Benadalid, Tania; Donaire, Johany; Salazar, Luis; Quirós-Rojas, Marianela; Portllo, Alejandro; Escobar, Pablo; Mejía, Raquel; Mireles, Monica; León, Antonis; Zelada, Cindy; Báez, Sol-haret; Ng,Jessica.

E20 (ESAOBELA 2020): Carrasco, Laura; Vargas, Camilo; Barba, Miguel; Martinez, Glenda; Castellanos, Mitsa; Mejia, Nicole; Buenfil, Guadalupe; Vásquez, Franklin; Martínez, Bexy; Beato, Manuel; Paredes, Jhonnayker; Muñoz, Fernanda; Salazar, Azalea.

AOA16: Juarez, Karen; Lozano, Karen; Padilla, Artemio; Velázquez, Roberto; Santillan, Priscila.

AOA18: Bustos, Sergio; Carrillo, José Luis; Chávez, Brian; Navez, David; Zuñiga, Ana.

AOA19: Briones, Joshua; Castro, Celeste; Martínez, Fernanda; Posadas, Hilde; Romero, Mitzi; Soberanes, Hilkar; Velasco, Alex.

AOA20: Blas, Karla; Madrigal, Norma; Perez, Alexis; Ramirez, Jos_e; Santiago, Beatríz.

Bo19 (Bolivia 19): Benadalid, Tania; Donaire, Johany; Muñoz, Ruber.

Ho19 (OACS Honduras 2019): Artola, Adán; Meza, Maria Renee; Mejia, Luis Fernando.

GIEP: Meza, María Renee; Argueta, Christian

References

Breger, M. 1966, ApJ, 146, 958 [ Links ]

Collins, K. A., Kielkopf, J. F., Stassun, K. G., & Hessman, F. V. 2017, AJ, 153, 77 [ Links ]

Millis, R. L. 1966, IBVS, 137, 1 [ Links ]

Peña, J. H., Villareal, C., Piña, D. S., et al. 2016, RMxAA, 52, 385 [ Links ]

Peña, J. H., Renteria, A., Villareal, C. et al. 2015, IBVS, 6154, 1 [ Links ]

Peña, J. H., Renteria, A., Piña, D., & Villareal, C. 2017, IBVS, 63, 6220 [ Links ]

Samus, N. N., Kazarovets, E. V., Durlevich, O. V., Kireeva, N. N., & Pastukhova, E. N. 2017, ARep, 61, 80 [ Links ]

Warman, J., Malacara, Z., & Breger, M. 1974, RMxAA, 1, 143 [ Links ]

Warman, J., Peña, J. H., & Arellano Ferro, A. 1979, AJ, 84, 109 [ Links ]

1Based on observations collected at the San Pedro Mártir and Tonantzintla Observatories, México, Tegucigalpa at Honduras and La Paz, Bolivia.

Received: July 23, 2020; Accepted: January 29, 2021

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