分类： 天文学 >> 天文学 提交时间： 2023-02-19
摘要： We analyse the pulsating behaviour of TIC 308396022 observed by the TESS mission. The star is a high-amplitude $\delta$ Sct star (HADS) that shows a very rich amplitude spectrum using the 3-yr light curve. Among these frequencies, the strongest peak of $f_{1}= 13.20362567(12) \rm{d^{-1}}$ is identified as the radial fundamental mode, and we also find the first and second overtones ($f_2$ and $f_3$). In the low frequency range (< 2.5 $\rm{d^{-1}}$), 22 peaks are identified to be gravity modes, which show a regular period spacing of about 2460\,s and have the angular degree $l = 1$. The period spacing pattern does not show a significant downward trend, suggesting the star rotates slowly. We note that this is a $\delta$ Sct--$\gamma$ Dor hybrid star containing a high-amplitude radial fundamental mode and a regular g-mode period spacing pattern. With O-C analysis, we find the star shows a significant time delay, implying that the star has a companion which is likely to be a white dwarf. The history of possible mass transfer provides a great opportunity to test the current theories of binary evolution, mass transfer, and pulsation.
分类： 天文学 >> 天文学 提交时间： 2023-02-19
摘要： We present the first catalogue of double-mode and multi-mode high amplitude $\delta$ Scuti star (HADS) in the Galaxy. The catalogue contains source name, coordinates, radial modes such as the fundamental (F, period P0), first-overtone (1O, period P1), second-overtone (2O, period P2), and the third-overtone (3O, period P3) if available, period ratios, magnitude, and the relevant literature. Totally, 155 sources were collected until March 2021, in which 142 HADS with double-mode (132 with F and 1O, and 10 with 1O and 2O), 11 triple-mode, and 2 quadruple-mode. Statistical analysis shows clear features: P0 lies in a range of 0.05 days to 0.175 days (sample: 132 double-mode HADS pulsating in F and 1O); P1/P0 lies in a range of 0.761 $-$ 0.787 (sample: 142 with P0 and P1), in which about 90\% in 0.765 $-$ 0.785, which is wider than previous studies. The Petersen diagram was created with a much larger sample (144 HADS with P0 and P1) and we find that stars with periods in 0.05 $-$ 0.1 days scatter largely from the updated linear relation (i.e., Eq.1), the reason of which however needs further investigation. Particularly, we discover that the ratio P2/P1 (sample: 21 HADS with P1 and P2) equals 0.802$\pm$0.004, which could be viewed as a possible indicator to identify the modes 1O and 2O for multi-mode HADS. In addition, several unusual stars are pointed out, which may need more attention to their pulsations and stellar parameters in the future.
分类： 天文学 >> 天文学 提交时间： 2023-02-19
Guo-Jie Feng
Ali Esamdin
Jian-Ning Fu
Hu-Biao Niu
Peng Zong
Tao-Zhi Yang
Shu-Guo Ma
Jing Xu
Chun-Hai Bai
Yong Wang
Wei-Chao Sun
Xin-Liang Wang
摘要： KIC 10417986 is a short orbital period (0.0737 d) ellipsoidal variable star with a {\delta} Scuti and {\gamma} Doradus hybrid pulsations component discovered by Kepler. The ground-based spectroscopic observations were carried out in the winters of 2020 and 2021 to investigate the binary nature of this star. We derive the orbital parameters using the rvfit code with a result of K1 = 29.7 $\pm$ 1.5 km/s, {\gamma} = -18.7 $\pm$ 1.7 km/s, and confirm an orbital period of 0.84495 d instead of the result given by Kepler. The atmospheric parameters of the primary are determined by the synthetic spectra fitting technique with the estimated values of Teff = 7411 $\pm$ 187 K, log g = 4.2 $\pm$ 0.3 dex, [M/H] = 0.08 $\pm$ 0.09 dex and vsini = 52 $\pm$ 11 km/s. KIC 10417986 is a circular orbit binary system. From the single-lined nature and mass function of the star, the derived orbital inclination is 26 $\pm$ 6{\deg}, and the mass of the secondary is from 0.43 to 0.7 M_sun, which should be a late-K to early-M type star. Fourteen frequencies are extracted from Kepler light curves, of which six independent frequencies in the high-frequency region are identified as the p-mode pulsations of {\delta} Scuti star, and one independent frequency in the low-frequency region (f2 = 1.3033 c/d) is probably the rotational frequency due to the starspots rather than the ellipsoidal effect or g-mode of {\gamma} Doradus.
分类： 心理学 >> 实验心理学 提交时间： 2017-10-13
Ning Yang
Ye He
Zhe Zhang
Hao-Ming Dong
Lei Zhang
Xing-Ting Zhu
Xiao-Hui Hou
Yin-Shan Wang
Quan Zhou
Zhu-QingGong
Li-Zhi Cao
Ping Wang
Yi-Wen Zhang
Dan-Yang Sui
TingXu1
Gao-Xia Wei
Zhi Yang
Lili Jiang
Hui-Jie Li
Ting-YongFeng
摘要： Abstract: To face the challenges of keeping healthy in increasing population sizes of both ageing and developing people in China, a fundamental request from the public health is the development of lifespan normative trajectories of brain and behavior. This paper introduces the Chinese Color Nest Project (CCNP 2013–2022), a large-scale tenyear program of modeling brain and behavioral trajectories for human lifespan (6–85 years old). We plan to gradually collect the behavioral and brain imaging data at ages across the lifespan on nationwide and depict the normal trajectory of Chinese brain development across the lifespan, based on the accelerated longitudinal design in the coming next 10 years starting at 2013. Various psychiatric disorders have been demonstrated highly relevant to abnormal events during the neurodevelopment regarding their onset ages of first episodes. Therefore, delineation of normative growth curves of brain and cognition in typically developing children is extremely useful for monitoring, early detecting and intervention of various neurodevelopmental disorders. In this paper, we detailed the developing part of CCNP, devCCNP. It tracked 192 healthy children and adolescents (6–18 years old) in Beibei district of Chongqing for the first 5 years of the full CCNP cohort (2013–2017). To demonstrate the feasibility of implementing the longterm follow-up of CCNP, we here comprehensively document devCCNP in terms of its experimental design, sample strategies, data acquisition and storage as well as some preliminary results and data sharing roadmap for future. Specifically, we first describe the accelerated longitudinal sampling design as well as its exact ratio of sample dropping off during the data collection. Second, we present several initial findings such as canonical growth curves of cortical surface areas of a set of well-established large-scale functional networks of the human brain. Finally, together with records generated by many psychological and behavioral tests, we will provide an individual growing-up report for each family participating the program, initiating the potential guidance on the individual academic and social development. The resources introduced in the current work can provide first-hand data for a series of coming Chinese brain development studies, such as Chinese Standard MRI Brain Templates, Normative Growth Curves of Chinese Brain and Cognition as well as Mapping of Language Areas in Chinese Developing Brain. These would not only offer normative references of the atypical brain and cognition development for Chinese population but also serve as a strong force on accelerating the pace of integrating Chinese brain development into the national brain program or Chinese Brain Project.
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