Pub Date : 2021-03-01DOI: 10.32023/0001-5237/71.1.2
R. Baluev, E. Sokov, I. Sokova, V. Shaidulin, A. V. Veselova, V. Aitov, G. Mitiani, A. Valeev, D. Gadelshin, A. Gutaev, G. Beskin, G. Valyavin, K. Antonyuk, K. Barkaoui, M. Gillon, E. Jehin, L. Delrez, S. Gudhmundsson, H. Dale, E. Fern'andez-Laj'us, R. Sisto, M. Bretton, A. Wunsche, V. Hentunen, S. Shadick, Y. Jongen, W. Kang, T. Kim, E. Pakvstien.e, J. Qvam, C. R. Knight, P. Guerra, A. Marchini, F. Salvaggio, R. Papini, P. Evans, M. Salisbury, J. Garlitz, N. Esseiva, Y. Ogmen, P. Bosch-Cabot, A. Selezneva, T. Hinse
We developed a dedicated statistical test for a massive detection of spot- and facula-crossing anomalies in multiple exoplanetary transit light curves, based on the frequentist p-value thresholding. This test was used to augment our algorithmic pipeline for transit light curves analysis. It was applied to 1598 amateur and professional transit observations of 26 targets being monitored in the EXPANSION project. We detected 109 statistically significant candidate events revealing a roughly 2:1 asymmetry in favor of spots-crossings over faculae-crossings. Although some candidate anomalies likely appear non-physical and originate from systematic errors, such asymmetry between negative and positive events should indicate a physical difference between the frequency of star spots and faculae. Detected spot-crossing events also reveal positive correlation between their amplitude and width, possibly due to spot size correlation. However, the frequency of all detectable crossing events appears just about a few per cent, so they cannot explain excessive transit timing noise observed for several targets.
{"title":"Massive Search for Spot- and Facula-Crossing Events in 1598 Exoplanetary Transit Light Curves","authors":"R. Baluev, E. Sokov, I. Sokova, V. Shaidulin, A. V. Veselova, V. Aitov, G. Mitiani, A. Valeev, D. Gadelshin, A. Gutaev, G. Beskin, G. Valyavin, K. Antonyuk, K. Barkaoui, M. Gillon, E. Jehin, L. Delrez, S. Gudhmundsson, H. Dale, E. Fern'andez-Laj'us, R. Sisto, M. Bretton, A. Wunsche, V. Hentunen, S. Shadick, Y. Jongen, W. Kang, T. Kim, E. Pakvstien.e, J. Qvam, C. R. Knight, P. Guerra, A. Marchini, F. Salvaggio, R. Papini, P. Evans, M. Salisbury, J. Garlitz, N. Esseiva, Y. Ogmen, P. Bosch-Cabot, A. Selezneva, T. Hinse","doi":"10.32023/0001-5237/71.1.2","DOIUrl":"https://doi.org/10.32023/0001-5237/71.1.2","url":null,"abstract":"We developed a dedicated statistical test for a massive detection of spot- and facula-crossing anomalies in multiple exoplanetary transit light curves, based on the frequentist p-value thresholding. This test was used to augment our algorithmic pipeline for transit light curves analysis. It was applied to 1598 amateur and professional transit observations of 26 targets being monitored in the EXPANSION project. We detected 109 statistically significant candidate events revealing a roughly 2:1 asymmetry in favor of spots-crossings over faculae-crossings. Although some candidate anomalies likely appear non-physical and originate from systematic errors, such asymmetry between negative and positive events should indicate a physical difference between the frequency of star spots and faculae. Detected spot-crossing events also reveal positive correlation between their amplitude and width, possibly due to spot size correlation. However, the frequency of all detectable crossing events appears just about a few per cent, so they cannot explain excessive transit timing noise observed for several targets.","PeriodicalId":44887,"journal":{"name":"Acta Astronomica","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41520439","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-01DOI: 10.32023/0001-5237/70.4.5
J. Smak
{"title":"On the Critical Mass Ratio for the 3:1 Resonance in Accretion Disks","authors":"J. Smak","doi":"10.32023/0001-5237/70.4.5","DOIUrl":"https://doi.org/10.32023/0001-5237/70.4.5","url":null,"abstract":"","PeriodicalId":44887,"journal":{"name":"Acta Astronomica","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45244159","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-01DOI: 10.32023/0001-5237/70.4.4
T. Weselak
{"title":"On the Relation between OH+, OH and CH+ Molecules, Neutral/Molecular Hydrogen and Major 5780/5797 DIBs","authors":"T. Weselak","doi":"10.32023/0001-5237/70.4.4","DOIUrl":"https://doi.org/10.32023/0001-5237/70.4.4","url":null,"abstract":"","PeriodicalId":44887,"journal":{"name":"Acta Astronomica","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44517199","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-01DOI: 10.32023/0001-5237/70.4.3
M. Rozyczka, W. Pych, I. Thompson, B. Mazur
{"title":"The Clusters AgeS Experiment (CASE). Variable Stars in the Field of the Globular Cluster NGC 3201 - a Supplement","authors":"M. Rozyczka, W. Pych, I. Thompson, B. Mazur","doi":"10.32023/0001-5237/70.4.3","DOIUrl":"https://doi.org/10.32023/0001-5237/70.4.3","url":null,"abstract":"","PeriodicalId":44887,"journal":{"name":"Acta Astronomica","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49309479","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-06-01DOI: 10.32023/0001-5237/70.2.4
R. Baluev, V. Shaidulin, A. V. Veselova
We use an improved wavelet analysis technique to reconstruct the $(U,V,W)$ velocity distribution for $sim 250000$ stars from Gaia DR2, residing in the solar neighborhood of $200$~pc. The 2D wavelet transforms for three bivariate distributions $(U,V)$, $(U,W)$, and $(V,W)$ were investigated. Though most of currently known (low-velocity) stellar moving groups are densely overlapped in these diagrams, our analysis allowed to detect and disentangle about twenty statistically significant 3D groups of stars with high velocities. Most of them appear new. We also discuss the issue of correct noise thresholding in the wavelet transform and highlight the importance of using a global rather than local statistic for that. Using of a local significance measure may lead to an overstated statistical confidence for individual patterns due to the effect of multiple testing.
{"title":"High-Velocity Moving Groups in the Solar Neighborhood in Gaia DR2","authors":"R. Baluev, V. Shaidulin, A. V. Veselova","doi":"10.32023/0001-5237/70.2.4","DOIUrl":"https://doi.org/10.32023/0001-5237/70.2.4","url":null,"abstract":"We use an improved wavelet analysis technique to reconstruct the $(U,V,W)$ velocity distribution for $sim 250000$ stars from Gaia DR2, residing in the solar neighborhood of $200$~pc. The 2D wavelet transforms for three bivariate distributions $(U,V)$, $(U,W)$, and $(V,W)$ were investigated. Though most of currently known (low-velocity) stellar moving groups are densely overlapped in these diagrams, our analysis allowed to detect and disentangle about twenty statistically significant 3D groups of stars with high velocities. Most of them appear new. We also discuss the issue of correct noise thresholding in the wavelet transform and highlight the importance of using a global rather than local statistic for that. Using of a local significance measure may lead to an overstated statistical confidence for individual patterns due to the effect of multiple testing.","PeriodicalId":44887,"journal":{"name":"Acta Astronomica","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2020-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49573317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-03-01DOI: 10.32023/0001-5237/70.1.3
I. Özavcı, D. Ozuyar, H. V. Şenavcı, M. Yılmaz, E. Bahar, Ö. Baştürk, T. Kılıçoğlu, A. Elmaslı, Ş. Çalışkan, D. D. Izci, O. Yorukoglu, S. Selam
{"title":"Orbital Period Analysis of Four Eclipsing Binaries XY Boo, RW Com, MR Del and AK Her","authors":"I. Özavcı, D. Ozuyar, H. V. Şenavcı, M. Yılmaz, E. Bahar, Ö. Baştürk, T. Kılıçoğlu, A. Elmaslı, Ş. Çalışkan, D. D. Izci, O. Yorukoglu, S. Selam","doi":"10.32023/0001-5237/70.1.3","DOIUrl":"https://doi.org/10.32023/0001-5237/70.1.3","url":null,"abstract":"","PeriodicalId":44887,"journal":{"name":"Acta Astronomica","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44892712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-03-01DOI: 10.32023/0001-5237/70.1.5
D. Garofalo, B. Webster, K. Bishop
{"title":"Merger Signatures in Radio Loud and Radio Quiet Quasars","authors":"D. Garofalo, B. Webster, K. Bishop","doi":"10.32023/0001-5237/70.1.5","DOIUrl":"https://doi.org/10.32023/0001-5237/70.1.5","url":null,"abstract":"","PeriodicalId":44887,"journal":{"name":"Acta Astronomica","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46280191","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-03-01DOI: 10.32023/0001-5237/70.1.4
J. J. Jiménez-Torres
{"title":"Multiple Stellar Encounters on Protoplanetary Disks in Birth Clusters of Stars","authors":"J. J. Jiménez-Torres","doi":"10.32023/0001-5237/70.1.4","DOIUrl":"https://doi.org/10.32023/0001-5237/70.1.4","url":null,"abstract":"","PeriodicalId":44887,"journal":{"name":"Acta Astronomica","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43889230","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-01-01DOI: 10.32023/0001-5237/70.1.2
A. L. Oriona, J. Ling, C. S. Sellero
{"title":"Photocenter Shift Effect in Double Stars of Gaia DR2 Database","authors":"A. L. Oriona, J. Ling, C. S. Sellero","doi":"10.32023/0001-5237/70.1.2","DOIUrl":"https://doi.org/10.32023/0001-5237/70.1.2","url":null,"abstract":"","PeriodicalId":44887,"journal":{"name":"Acta Astronomica","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69520927","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}