In the Antarctic Ice core there exist many nitrate ion concentration spikes due to gamma ray. A part of the ice core extracted from the Japanese Antarctic station named Dome Fuji,corresponding with 11th century, shows three set of spikes.The first two possibly coincide with SN1006 and SN1054.The third one is probably due to the symbiotic binary R Auarii's outbursts (1073 and 1074AD)that were recorded in the ancient Korean documents as a "guest star". Moreover,there exist several nitrate ion spikes corresponding with other centuries. Some of the spikes without any historical records are possibly due to the gamma-ray from invisible or missing SNe or other (classical novae or symbiotic star )outbursts.
{"title":"R Aquarii and Gamma Ray Astronomy","authors":"K. Tanabe, Y. Motizuki","doi":"10.22323/1.315.0062","DOIUrl":"https://doi.org/10.22323/1.315.0062","url":null,"abstract":"In the Antarctic Ice core there exist many nitrate ion concentration spikes due to gamma ray. A part of the ice core extracted from the Japanese Antarctic station named Dome Fuji,corresponding with 11th century, shows three set of spikes.The first two possibly coincide with SN1006 and SN1054.The third one is probably due to the symbiotic binary R Auarii's outbursts (1073 and 1074AD)that were recorded in the ancient Korean documents as a \"guest star\". Moreover,there exist several nitrate ion spikes corresponding with other centuries. Some of the spikes without any historical records are possibly due to the gamma-ray from invisible or missing SNe or other (classical novae or symbiotic star )outbursts.","PeriodicalId":71342,"journal":{"name":"黄金时代","volume":"34 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82100290","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}
Cataclysmic Variables (CVs) are binary systems made of a white dwarf which is accreting mass from a less evolved companion. Depending on the physical properties of the system, the observational characteristics of CVs can be very diverse. Nevertheless, as we learned from projects like the Sloan Digital Sky Survey, CVs occupy the same locus of quasars in color-color diagrams, hence their discovery can be quite challenging. In this paper, we expose how the filter set of the J-PLUS project can help to efficiently separate CVs from other objects (mostly quasars) and even get their type. Through simulations and real data, we explain how accurate the method is and identify the following steps to finally get the first complete unbiased magnitude-limited sample of Cataclysmic Variables to date, a fundamental data set to be able to study the evolution of this type of objects.
{"title":"Search for CVs in wide-field narrow-band photometric survey","authors":"J. Abril, A. Ederoclite, L. Schmidtobreick","doi":"10.22323/1.315.0010","DOIUrl":"https://doi.org/10.22323/1.315.0010","url":null,"abstract":"Cataclysmic Variables (CVs) are binary systems made of a white dwarf which is accreting mass from a less evolved companion. Depending on the physical properties of the system, the observational characteristics of CVs can be very diverse. Nevertheless, as we learned from projects like the Sloan Digital Sky Survey, CVs occupy the same locus of quasars in color-color diagrams, hence their discovery can be quite challenging. In this paper, we expose how the filter set of the J-PLUS project can help to efficiently separate CVs from other objects (mostly quasars) and even get their type. Through simulations and real data, we explain how accurate the method is and identify the following steps to finally get the first complete unbiased magnitude-limited sample of Cataclysmic Variables to date, a fundamental data set to be able to study the evolution of this type of objects.","PeriodicalId":71342,"journal":{"name":"黄金时代","volume":"17 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74113150","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}
We report our photometric observational results during the early stage of 2017 outburst of an ultra short orbital period cataclysmic variable star OV Bootis. From the obtained light curve, its period of the hump-like modulation is quite close to its orbital one This result suggests us that this variable star is thought to be neither WZ Sge-type nor SU UMa-type dwarf nova ,taking into account the absence of rebrightening.
{"title":"Photometry of OV Bootis at the Early Stage of 2017 Outburst","authors":"K. Tanabe, H. Akazawa, N. Fukuda","doi":"10.22323/1.315.0044","DOIUrl":"https://doi.org/10.22323/1.315.0044","url":null,"abstract":"We report our photometric observational results during the early stage of 2017 outburst of an ultra short orbital period cataclysmic variable star OV Bootis. From the obtained light curve, its period of the hump-like modulation is quite close to its orbital one This result suggests us that this variable star is thought to be neither WZ Sge-type nor SU UMa-type dwarf nova ,taking into account the absence of rebrightening.","PeriodicalId":71342,"journal":{"name":"黄金时代","volume":"26 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72870819","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}
We review our current understanding of multiwavelength light curves of classical and recurrent novae and show how to determine the WD masses and other binary properties. We pick up PW Vul, U Sco, V745 Sco, RS Oph, and V407 Cyg as representatives of different types of light curves, examine their light curves in detail, discuss physical properties, and clarify the reason of these differences. In the rising phase, the hydrogen-rich envelope expands beyond the size of a close binary in which the companion is embedded deep inside of the photosphere. After the optical maximum, the pseud-photosphere begins to shrink and an optically thin region develops outside of the photosphere. The free-free emission dominates the flux at relatively longer wavelengths (optical and NIR), of which light curves decay along the universal decline law of $F_nu propto t^{-1.75}$ (or $t^{-1.55}$). The physical mechanism of super-Eddington phase is presented. In the presence of shock interaction between ejecta and circumstellar matter, it slows down the decay of optical flux as $F_nu propto t^{-1.0}$ as seen in the early phase of V407 Cyg. In final stages of outbursts, the wind mass-loss rate sharply drops so the slope of free-free emission decays like $F_nu propto t^{-3.5}$. Supersoft X-ray phase begins and continues until hydrogen nuclear burning ends, and after that the nova enters a cooling phase. Hard X-rays may originate from internal shocks between ejecta (or a bow shock between ejecta and the companion). The behaviors of optical-dominant, UV-dominant, and supersoft X-ray source phase have different dependences on the WD mass and envelope chemical composition, so multiwavelength observations are useful to determine the parameters such as the WD mass. Finally, we should note that the very early phase of nova outbursts remains unexplored. An X-ray flash phase is theoretically identified, but not yet successfully detected. Detections of early X-ray flashes give direct information on thermonuclear runaway.
{"title":"Multifrequency behavior of classical novae","authors":"I. Hachisu, M. Kato","doi":"10.22323/1.315.0047","DOIUrl":"https://doi.org/10.22323/1.315.0047","url":null,"abstract":"We review our current understanding of multiwavelength light curves of classical and recurrent novae and show how to determine the WD masses and other binary properties. We pick up PW Vul, U Sco, V745 Sco, RS Oph, and V407 Cyg as representatives of different types of light curves, examine their light curves in detail, discuss physical properties, and clarify the reason of these differences. In the rising phase, the hydrogen-rich envelope expands beyond the size of a close binary in which the companion is embedded deep inside of the photosphere. After the optical maximum, the pseud-photosphere begins to shrink and an optically thin region develops outside of the photosphere. The free-free emission dominates the flux at relatively longer wavelengths (optical and NIR), of which light curves decay along the universal decline law of $F_nu propto t^{-1.75}$ (or $t^{-1.55}$). The physical mechanism of super-Eddington phase is presented. In the presence of shock interaction between ejecta and circumstellar matter, it slows down the decay of optical flux as $F_nu propto t^{-1.0}$ as seen in the early phase of V407 Cyg. In final stages of outbursts, the wind mass-loss rate sharply drops so the slope of free-free emission decays like $F_nu propto t^{-3.5}$. Supersoft X-ray phase begins and continues until hydrogen nuclear burning ends, and after that the nova enters a cooling phase. Hard X-rays may originate from internal shocks between ejecta (or a bow shock between ejecta and the companion). The behaviors of optical-dominant, UV-dominant, and supersoft X-ray source phase have different dependences on the WD mass and envelope chemical composition, so multiwavelength observations are useful to determine the parameters such as the WD mass. Finally, we should note that the very early phase of nova outbursts remains unexplored. An X-ray flash phase is theoretically identified, but not yet successfully detected. Detections of early X-ray flashes give direct information on thermonuclear runaway.","PeriodicalId":71342,"journal":{"name":"黄金时代","volume":"39 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87473502","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}
Standard evolutionary theory suggests that cataclysmic variables (CVs) evolve from longer to shorter orbital periods. CVs that have passed beyond the period minimum and are evolving back towards longer periods are called the period bouncers. CVs of the WZ Sge-type have been long considered as potential period-bounce candidates. However, only very few of recently discovered WZ Sge-type stars were observed spectroscopically in quiescence due to their faintness. The lack of information on many of WZ Sge-type stars does not allow us to put restrictions on their system parameters and to confirm or deny their period bounce nature. Here we present a novel, simpler yet equally valuable approach based on multicolour broadband photometry to reveal the best period bounce candidates. By adopting such an approach, we performed a pilot study of a sample of WZ~Sge-type objects and accreting WDs and have found solid evidence for very low luminosity donor stars in several of them.
{"title":"Systematic search for post period-minimum cataclysmic variables: A short review","authors":"V. Neustroev, C. Knigge, S. Zharikov","doi":"10.22323/1.315.0034","DOIUrl":"https://doi.org/10.22323/1.315.0034","url":null,"abstract":"Standard evolutionary theory suggests that cataclysmic variables (CVs) evolve from longer to shorter orbital periods. CVs that have passed beyond the period minimum and are evolving back towards longer periods are called the period bouncers. CVs of the WZ Sge-type have been long considered as potential period-bounce candidates. However, only very few of recently discovered WZ Sge-type stars were observed spectroscopically in quiescence due to their faintness. The lack of information on many of WZ Sge-type stars does not allow us to put restrictions on their system parameters and to confirm or deny their period bounce nature. Here we present a novel, simpler yet equally valuable approach based on multicolour broadband photometry to reveal the best period bounce candidates. By adopting such an approach, we performed a pilot study of a sample of WZ~Sge-type objects and accreting WDs and have found solid evidence for very low luminosity donor stars in several of them.","PeriodicalId":71342,"journal":{"name":"黄金时代","volume":"54 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87786341","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}
A. Ederoclite, C. Tappert, L. Schmidtobreick, N. Vogt
Classical novae are important astrophysical laboratories and are extremely relevant in several aspects of modern astronomy. A complete understanding of the nova phenomenon passes through the understanding not only of the phase where the nova is bright, but also understanding the properties of the binaries in which these events occur. This paper focusses on the properties of Cataclysmic Variables (CVs) which have harboured a nova explosion more than 30 years ago. The objects are analysed both in terms of CV population and in relation to their properties at maximum. Finally, we advice the reader on the proper steps in order to use old novae in the Gaia era.
{"title":"Old Novae: Old Glories with Bright Future","authors":"A. Ederoclite, C. Tappert, L. Schmidtobreick, N. Vogt","doi":"10.22323/1.315.0045","DOIUrl":"https://doi.org/10.22323/1.315.0045","url":null,"abstract":"Classical novae are important astrophysical laboratories and are extremely relevant in several aspects of modern astronomy. A complete understanding of the nova phenomenon passes through the understanding not only of the phase where the nova is bright, but also understanding the properties of the binaries in which these events occur. \u0000 \u0000This paper focusses on the properties of Cataclysmic Variables (CVs) which have harboured a nova explosion more than 30 years ago. The objects are analysed both in terms of CV population and in relation to their properties at maximum. \u0000Finally, we advice the reader on the proper steps in order to use old novae in the Gaia era.","PeriodicalId":71342,"journal":{"name":"黄金时代","volume":"35 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85568274","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 mass growth rate of mass-accreting white dwarfs (WDs) is a key factor in binary evolution scenarios toward Type Ia supernovae. Many authors have reported very different WD mass increasing rates. In this review, we clarify the reasons for such divergence, some of which come from a lack of numerical techniques, usage of old opacities, different assumptions for binary configurations, inadequate initial conditions, and unrealistic mass-loss mechanisms. We emphasize that these assumptions should be carefully chosen in calculating the long-term evolution of accreting WDs. Importantly, the mass-loss mechanism is the key process determining the mass retention efficiency: the best approach involves correctly incorporating the optically thick wind because it is supported by the multiwavelength light curves of novae.
{"title":"Recurrent novae and long-term evolution of mass-accreting white dwarfs – toward the accurate mass retention efficiency","authors":"M. Kato, I. Hachisu, H. Saio","doi":"10.22323/1.315.0056","DOIUrl":"https://doi.org/10.22323/1.315.0056","url":null,"abstract":"The mass growth rate of mass-accreting white dwarfs (WDs) is a key factor in binary evolution scenarios toward Type Ia supernovae. Many authors have reported very different WD mass increasing rates. In this review, we clarify the reasons for such divergence, some of which come from a lack of numerical techniques, usage of old opacities, different assumptions for binary configurations, inadequate initial conditions, and unrealistic mass-loss mechanisms. We emphasize that these assumptions should be carefully chosen in calculating the long-term evolution of accreting WDs. Importantly, the mass-loss mechanism is the key process determining the mass retention efficiency: the best approach involves correctly incorporating the optically thick wind because it is supported by the multiwavelength light curves of novae.","PeriodicalId":71342,"journal":{"name":"黄金时代","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82966282","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 soft excess is a spectral feature shown by many polar cataclysmic variables, resembling a very luminous blackbody in soft X-rays. It is thought to arise from the accretion of discrete blobs of gas onto the WD, and was found in all polars discovered prior to the end of the ROSAT mission. All polars discovered since then seem to lack it, and the reason is still unknown. Here we present an XMM-Newton study of four polars discovered optically in recent years. All four lack the soft excess, and we test the hypothesis that the sought-after spectral feature might be concealed in the very soft X-ray regime unobservable by XMM-Newton.
{"title":"X-ray and optical observations of polars","authors":"H. Worpel, A. Schwope","doi":"10.22323/1.315.0019","DOIUrl":"https://doi.org/10.22323/1.315.0019","url":null,"abstract":"The soft excess is a spectral feature shown by many polar cataclysmic variables, resembling a very luminous blackbody in soft X-rays. It is thought to arise from the accretion of discrete blobs of gas onto the WD, and was found in all polars discovered prior to the end of the ROSAT mission. All polars discovered since then seem to lack it, and the reason is still unknown. \u0000 \u0000Here we present an XMM-Newton study of four polars discovered optically in recent years. All four lack the soft excess, and we test the hypothesis that the sought-after spectral feature might be concealed in the very soft X-ray regime unobservable by XMM-Newton.","PeriodicalId":71342,"journal":{"name":"黄金时代","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80233454","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}
We report on the latest results from Hubble Space Telescope (HST) far ultraviolet spectroscopy with the Cosmic Object Spectrograph (COS), of the short orbital period recurrent novae (RNe) T Pyxidis, IM Norma (the first ever FUV spectrum of this RN) and CI Aquilae, the only known recurrent novae with main sequence donors and orbital periods less than a day. The last two HST COS spectra we obtained in October, 2016 and June, 2016, reveal that the accretion rate of T Pyx has declined by 20% below its quiescent continuum flux level recorded by the IUE following the 1966 outburst, an indication that the system might not have yet reached its (new) quiescent state. Recent HST COS Spectroscopy of the cooling of the white dwarf in the prototypical dwarf nova U Geminorum is also discussed with a focus on the chemical abundances in the white dwarf photosphere.
我们报告了哈勃太空望远镜(HST)和宇宙物体光谱仪(COS)对短轨道周期复发新星(RNe) T Pyxidis, IM Norma(该RN的第一个FUV光谱)和CI Aquilae的最新结果,这是唯一已知的主序供体和轨道周期小于一天的复发新星。我们在2016年10月和2016年6月获得的最后两幅HST COS光谱显示,T Pyx的吸积速率比IUE记录的1966年爆发后的静态连续通量水平下降了20%,这表明该系统可能尚未达到(新的)静态状态。本文还讨论了典型矮新星U Geminorum中白矮星冷却的HST COS光谱,重点讨论了白矮星光球中的化学丰度。
{"title":"The Hot Components in the Recurrent Novae T Pyxidis, IM Norma, CI Aquilae and in the Dwarf Nova U Geminorum","authors":"E. Sion, P. Godon","doi":"10.22323/1.315.0058","DOIUrl":"https://doi.org/10.22323/1.315.0058","url":null,"abstract":"We report on the latest results from Hubble Space Telescope (HST) far ultraviolet spectroscopy \u0000with the Cosmic Object Spectrograph (COS), of the short orbital period recurrent novae (RNe) \u0000T Pyxidis, IM Norma (the first ever FUV spectrum of this RN) and CI Aquilae, the only known \u0000recurrent novae with main sequence donors and orbital periods less than a day. The last two HST \u0000COS spectra we obtained in October, 2016 and June, 2016, reveal that the accretion rate of T \u0000Pyx has declined by 20% below its quiescent continuum flux level recorded by the IUE following \u0000the 1966 outburst, an indication that the system might not have yet reached its (new) quiescent \u0000state. Recent HST COS Spectroscopy of the cooling of the white dwarf in the prototypical dwarf \u0000nova U Geminorum is also discussed with a focus on the chemical abundances in the white dwarf \u0000photosphere.","PeriodicalId":71342,"journal":{"name":"黄金时代","volume":"48 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84302446","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}
We report on the 2015 February-March superoutburst of the well known SU UMa-type dwarf novae QZ Vir (= T Leo). The light curve showed a unique feature in which the precursor was completely separated from the main superoutburst. During the stage between the precursor and main superoutburst, we detected superhumps with the mean period of 0.061181(42) d. Based on the amplitudes and $O - C$ analyses of superhumps, we identified the observed superhump during the faint stage as stage A superhumps. Using the orbital and stage A superhump period of QZ Vir, we derived the mass ratio to be 0.108(3). This value indicates that the system is an SU UMa-type dwarf novae evolving toward the period minimum. Here we briefly discuss that long-lasting growing superhumps can offer an opportunity to examine the evolutional status of SU UMa-type dwarf novae with moderate orbital periods, and future strategies of photometry of SU UMa-type dwarf novae.
我们报道了2015年2 - 3月著名的SU uma型矮新星QZ Vir (= T Leo)的超爆发。光曲线显示出一个独特的特征,即前驱体与主超突出完全分离。在前体和主超突出之间的阶段,我们探测到平均周期为0.061181(42)d的超级峰。根据超级峰的振幅和$O - C$分析,我们确定在微弱阶段观测到的超级峰为A级超级峰。利用QZ Vir的轨道和A级超峰周期,我们推导出质量比为0.108(3)。该值表明该系统是一颗向最小周期演化的SU - uma型矮新星。在此,我们简要地讨论了长时间生长的超级驼峰可以为研究中等轨道周期的SU - uma型矮新星的演化状态提供机会,以及SU - uma型矮新星光度测量的未来策略。
{"title":"Long-lasting growing superhumps in SU UMa stars: QZ Vir","authors":"A. Imada, Taichi Kato, K. Isogai","doi":"10.22323/1.315.0014","DOIUrl":"https://doi.org/10.22323/1.315.0014","url":null,"abstract":"We report on the 2015 February-March superoutburst of the well known SU UMa-type dwarf novae QZ Vir (= T Leo). The light curve showed a unique feature in which the precursor was completely separated from the main superoutburst. During the stage between the precursor and main superoutburst, we detected superhumps with the mean period of 0.061181(42) d. Based on the amplitudes and $O - C$ analyses of superhumps, we identified the observed superhump during the faint stage as stage A superhumps. Using the orbital and stage A superhump period of QZ Vir, we derived the mass ratio to be 0.108(3). This value indicates that the system is an SU UMa-type dwarf novae evolving toward the period minimum. Here we briefly discuss that long-lasting growing superhumps can offer an opportunity to examine the evolutional status of SU UMa-type dwarf novae with moderate orbital periods, and future strategies of photometry of SU UMa-type dwarf novae.","PeriodicalId":71342,"journal":{"name":"黄金时代","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91202736","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}