We have performed a new search for DPVs of short period in the ASAS catalog (Pojmanski, G., 1997), focusing on those stars with orbital periods between 2 to 3 days which also show variations in their brightness. From a total of 244 objects, we have found another candidate to DPV, one whose mean brightness is gradually decreasing. By fitting a 3rd order polynomial to the mean magnitude and then moving it to zero for a second analysis, a gradual decrease over 2500 days was revealed. During the last 1000 days of this decrease, a 42% increase in the variation between the minimum and maximum values of the magnitude was observed. We determined the orbital period by using the PDM IRAF software (Stellingwerf 1978) and estimated the errors for the orbital period and long cycle by visual inspection of the light curves phased with trial periods near the minimum of the periodogram given by PDM.
{"title":"TYC 5353-1137-1: an enigmatic Doubly Periodic Variable of semiregular amplitude","authors":"J. Rosales, R. Mennickent","doi":"10.22444/IBVS.6248","DOIUrl":"https://doi.org/10.22444/IBVS.6248","url":null,"abstract":"We have performed a new search for DPVs of short period in the ASAS catalog (Pojmanski, G., 1997), focusing on those stars with orbital periods between 2 to 3 days which also show variations in their brightness. From a total of 244 objects, we have found another candidate to DPV, one whose mean brightness is gradually decreasing. By fitting a 3rd order polynomial to the mean magnitude and then moving it to zero for a second analysis, a gradual decrease over 2500 days was revealed. During the last 1000 days of this decrease, a 42% increase in the variation between the minimum and maximum values of the magnitude was observed. We determined the orbital period by using the PDM IRAF software (Stellingwerf 1978) and estimated the errors for the orbital period and long cycle by visual inspection of the light curves phased with trial periods near the minimum of the periodogram given by PDM.","PeriodicalId":35213,"journal":{"name":"Information Bulletin on Variable Stars","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48012337","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The Status of GSC 3870-01172 as a Member of a Triple or Quadruple System","authors":"D. Terrell, R. Nelson","doi":"10.22444/IBVS.6247","DOIUrl":"https://doi.org/10.22444/IBVS.6247","url":null,"abstract":"","PeriodicalId":35213,"journal":{"name":"Information Bulletin on Variable Stars","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47308549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
F. Aliçavuş, A. Raheem, G. Ç. Coban, E. M. Tambulut, Ü. Gögülter, L. Bas, B. Çevirici
{"title":"Photometry of GS UMa: a suspected {delta} Scuti variable","authors":"F. Aliçavuş, A. Raheem, G. Ç. Coban, E. M. Tambulut, Ü. Gögülter, L. Bas, B. Çevirici","doi":"10.22444/IBVS.6246","DOIUrl":"https://doi.org/10.22444/IBVS.6246","url":null,"abstract":"","PeriodicalId":35213,"journal":{"name":"Information Bulletin on Variable Stars","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44048701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K. Grankin, V. Shenavrin, T. Irsmambetova, P. Petrov
In three seasons of 2015-2018 we carried out a series of visible and near infrared (NIR) photometry of SU Aur. In course of this photometric monitoring we detected an event of a deep fading of the star in spring of 2018. In this paper we present preliminary analysis of our photometry.
{"title":"SU Aur: A deep fading event in Visible and near-infrared bands","authors":"K. Grankin, V. Shenavrin, T. Irsmambetova, P. Petrov","doi":"10.22444/IBVS.6253","DOIUrl":"https://doi.org/10.22444/IBVS.6253","url":null,"abstract":"In three seasons of 2015-2018 we carried out a series of visible and near infrared (NIR) photometry of SU Aur. In course of this photometric monitoring we detected an event of a deep fading of the star in spring of 2018. In this paper we present preliminary analysis of our photometry.","PeriodicalId":35213,"journal":{"name":"Information Bulletin on Variable Stars","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48201764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The existence of an additional body around a binary system can be detected by the help of the light-travel time effect. Due to the motions of binary and the companion stars around the common mass center of the ternary system, the light-time effect produces an irregularity on the eclipse timings. Monitoring the variations in these timings, sub-stellar or planet companions orbiting around the binary system can be identified. In this paper, additional bodies orbiting the Algol type binary DI Peg are examined by using the archival eclipse timings including our CCD data observed at the Ankara University Kreiken Observatory. More than five hundred minimum times equivalent to around nine decades are employed to identify the orbital behavior of the binary system. The best fit to the timings shows that the orbital period of DI Peg has variation due to an integration of two sinusoids with the periods of $P_3 = 49.50pm0.36$ yr and $P_4 = 27.40pm0.24$ yr. The orbital change is thought to be most likely due to the existence of two M-type red dwarf companions with the masses of $M_3 =0.213 pm 0.021$ M$_odot$ and $M_4 = 0.151 pm 0.008$ M$_odot$, assuming that the orbits of additional bodies are co-planar with the orbit of the binary system. Also, the residuals of two sinusoidal fits still seem to show another modulation with the period of roughly $P = 19.5$ yr. The origin of this modulation is not clear and more observational data are required to reveal if the periodicity is caused by another object gravitationally bounded to the system.
{"title":"The Period Analysis of the Hierarchical System DI Peg","authors":"Dogus Ozuyar, A. Elmaslı, S. Caliskan","doi":"10.22444/IBVS.6252","DOIUrl":"https://doi.org/10.22444/IBVS.6252","url":null,"abstract":"The existence of an additional body around a binary system can be detected by the help of the light-travel time effect. Due to the motions of binary and the companion stars around the common mass center of the ternary system, the light-time effect produces an irregularity on the eclipse timings. Monitoring the variations in these timings, sub-stellar or planet companions orbiting around the binary system can be identified. In this paper, additional bodies orbiting the Algol type binary DI Peg are examined by using the archival eclipse timings including our CCD data observed at the Ankara University Kreiken Observatory. More than five hundred minimum times equivalent to around nine decades are employed to identify the orbital behavior of the binary system. The best fit to the timings shows that the orbital period of DI Peg has variation due to an integration of two sinusoids with the periods of $P_3 = 49.50pm0.36$ yr and $P_4 = 27.40pm0.24$ yr. The orbital change is thought to be most likely due to the existence of two M-type red dwarf companions with the masses of $M_3 =0.213 pm 0.021$ M$_odot$ and $M_4 = 0.151 pm 0.008$ M$_odot$, assuming that the orbits of additional bodies are co-planar with the orbit of the binary system. Also, the residuals of two sinusoidal fits still seem to show another modulation with the period of roughly $P = 19.5$ yr. The origin of this modulation is not clear and more observational data are required to reveal if the periodicity is caused by another object gravitationally bounded to the system.","PeriodicalId":35213,"journal":{"name":"Information Bulletin on Variable Stars","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48113066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Maciejewski, M. Stangret, J. Ohlert, Ç. S. Başaran, J. Maciejczak, M. Puciata-Mroczynska, E. Boulanger
We present new transit observations acquired between 2014 and 2018 for the hot exoplanets GJ 436 b, HAT-P-3 b, HAT-P-19 b, WASP-3 b, and XO-2 b. New mid-transit times extend the timespan covered by observations of these exoplanets and allow us to refine their transit ephemerides. All new transits are consistent with linear ephemerides.
{"title":"New transit timing observations for GJ 436 b, HAT-P-3 b, HAT-P-19 b, WASP-3 b, and XO-2 b","authors":"G. Maciejewski, M. Stangret, J. Ohlert, Ç. S. Başaran, J. Maciejczak, M. Puciata-Mroczynska, E. Boulanger","doi":"10.22444/IBVS.6243","DOIUrl":"https://doi.org/10.22444/IBVS.6243","url":null,"abstract":"We present new transit observations acquired between 2014 and 2018 for the hot exoplanets GJ 436 b, HAT-P-3 b, HAT-P-19 b, WASP-3 b, and XO-2 b. New mid-transit times extend the timespan covered by observations of these exoplanets and allow us to refine their transit ephemerides. All new transits are consistent with linear ephemerides.","PeriodicalId":35213,"journal":{"name":"Information Bulletin on Variable Stars","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44426624","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Revised coordinates of 3 variable stars in Cygnus","authors":"R. Nesci","doi":"10.22444/IBVS.6242","DOIUrl":"https://doi.org/10.22444/IBVS.6242","url":null,"abstract":"","PeriodicalId":35213,"journal":{"name":"Information Bulletin on Variable Stars","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44859764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this paper, the period evolution of the rotating chemically peculiar star V473,Tau is investigated. Even though the star has been observed for more than fifty years, for the first time four consecutive years of space-based data covering between 2007 and 2010 are presented. The data are from the {sl STEREO} satellite, and are combined with the archival results. The analysis shows that the rotation period of V473,Tau is $1.406829(10)$ days, and has slightly decreased with the variation rate of 0.11(3)~s~yr$^{-1}$ over time. Also, the acceleration timescale of the star is found to be shorter than its main sequence lifetime. This indicates that the process of decrease in period might be reversible. On this basis, it can be suggested that V473,Tau has a possible magnetic acceleration and a differential rotation, which cause a variation in the movement of inertia, and hence the observed period change. Additionally, the evolution path of V473,Tau on the H-R diagram is evaluated. Accordingly, the position of the star on the diagram suggests that its magnetic properties develop before it reaches the main sequence or in the beginning of its main sequence lifetime.
{"title":"The Period Evolution of V473 Tau","authors":"D. Ozuyar, I. Stevens","doi":"10.22444/IBVS.6245","DOIUrl":"https://doi.org/10.22444/IBVS.6245","url":null,"abstract":"In this paper, the period evolution of the rotating chemically peculiar star V473,Tau is investigated. Even though the star has been observed for more than fifty years, for the first time four consecutive years of space-based data covering between 2007 and 2010 are presented. The data are from the {sl STEREO} satellite, and are combined with the archival results. The analysis shows that the rotation period of V473,Tau is $1.406829(10)$ days, and has slightly decreased with the variation rate of 0.11(3)~s~yr$^{-1}$ over time. Also, the acceleration timescale of the star is found to be shorter than its main sequence lifetime. This indicates that the process of decrease in period might be reversible. On this basis, it can be suggested that V473,Tau has a possible magnetic acceleration and a differential rotation, which cause a variation in the movement of inertia, and hence the observed period change. Additionally, the evolution path of V473,Tau on the H-R diagram is evaluated. Accordingly, the position of the star on the diagram suggests that its magnetic properties develop before it reaches the main sequence or in the beginning of its main sequence lifetime.","PeriodicalId":35213,"journal":{"name":"Information Bulletin on Variable Stars","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44736250","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Susanne Blex, M. Hackstein, M. Haas, S. Kimeswenger, R. Chini, K. Hodapp
{"title":"2MASS J06422218-0226285 - a new Outburst Source","authors":"Susanne Blex, M. Hackstein, M. Haas, S. Kimeswenger, R. Chini, K. Hodapp","doi":"10.22444/ibvs.6240","DOIUrl":"https://doi.org/10.22444/ibvs.6240","url":null,"abstract":"","PeriodicalId":35213,"journal":{"name":"Information Bulletin on Variable Stars","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46649298","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Revised coordinates of variable stars in Cassiopeia","authors":"R. Nesci","doi":"10.22444/IBVS.6236","DOIUrl":"https://doi.org/10.22444/IBVS.6236","url":null,"abstract":"","PeriodicalId":35213,"journal":{"name":"Information Bulletin on Variable Stars","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48010245","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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