Astrophysics最新文献_第7页

Activity of the Young Star EPIC 204376071 from the Upper SCO Association 上海合作组织高层协会青年星EPIC 204376071的活动

IF 0.5 4区物理与天体物理

Astrophysics Pub Date : 2023-09-29 DOI: 10.1007/s10511-023-09795-x

I. S. Savanov

{"title":"Activity of the Young Star EPIC 204376071 from the Upper SCO Association","authors":"I. S. Savanov","doi":"10.1007/s10511-023-09795-x","DOIUrl":"10.1007/s10511-023-09795-x","url":null,"abstract":"<div><div><p>Based on observations from the K2 mission of the Kepler Space Telescope a study is made of the activity of EPIC 204376071, a young object in the Upper SCO association with an age of 11±3 million years whose light curve has a single darkening lasting one day with a depth of about 80%. EPIC 204376071 is a low-mass M-dwarf with a mass of 0.16 M<sub>⨀</sub>. Based on observations from the C15 campaign of the K2 mission we refined the rotation period and the amplitude of the variability of the star’s brightness, and also estimated the absolute magnitude of the spottedness parameter A by the standard method. The magnitude of the star’s rotation period, P, equals 1.6270 ± 0.030 days. The area of the spots on the surface of EPIC 204376071 exceeds the maximum spot area on the sun and is on the order of 7900 msh. The results of a recovery of the temperature inhomogeneities on the surface of EPIC 204376071 are presented. Two cold regions separated in longitude by roughly 150° can be distinguished on the constructed chart. For estimating the properties of the flare activity of EPIC 204376071 one of the most reliable flares with a brightness amplitude of about 4% was examined. The measured relative energy RE of the flare was 212 s. The calculated energy E<sub>fl</sub> of the flare turned out to be equal to 1.1·1034 erg (logE<sub>fl</sub> = 34.05). The probable coronal mass ejection corresponding to it may reach 4.1·10<sup>20</sup> g. Published data on the possible nature of the single occultation of diurnal duration with a depth of about 80% on the light curve of EPIC 204376071 are examined.</p></div></div>","PeriodicalId":479,"journal":{"name":"Astrophysics","volume":"66 3","pages":"344 - 352"},"PeriodicalIF":0.5,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41087374","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}

引用次数: 0

The Revisited BPT Diagram from the Self-Consistent Analysis 自洽分析对BPT图的修正

IF 0.5 4区物理与天体物理

Astrophysics Pub Date : 2023-09-29 DOI: 10.1007/s10511-023-09793-z

P. Privatus, C. Pappalardo, P. V. K. Rao, D. T. Mazengo

{"title":"The Revisited BPT Diagram from the Self-Consistent Analysis","authors":"P. Privatus, C. Pappalardo, P. V. K. Rao, D. T. Mazengo","doi":"10.1007/s10511-023-09793-z","DOIUrl":"10.1007/s10511-023-09793-z","url":null,"abstract":"<div><div><p>Galaxies' spectral energy distribution has been explored through the use of spectral synthesis codes, and these techniques have been essential in identifying many aspects of the current galaxy evolution model. Most of the spectral synthesis codes that have been developed so far are solely stellar and assume a negligible nebular contribution to the overall continuum. FADO (Fitting Analysis using Differential Evolution Optimisation) is the first spectral synthesis code to fit self-consistently stellar and nebular components. Diagnostic diagrams are powerful tools for classifying galaxies based on the emission line ratio of collisionally excited lines such as [OIII] λ 5007, [NII] λ 6584, [SII] λ 6716, 6731, [OI] λ 6300, and the Balmer recombination lines such as Hα, Hβ. This paper explores the impact of including nebular components on diagnostic diagrams. We investigated the results of the application of FADO to the Sloan Digital Sky Survey Data Release 8 using the data analysed by MPA-JHU, the Max Planck Institute for Astrophysics, and Johns Hopkins University. We found that in all diagnostic diagrams, the fluxes for FADO are higher than those for MPA-JHU; the difference is significant compared to the error in the flux measurement. FADO overestimates the flux ratio of all three diagnostic diagrams over MPA-JHU, but the overestimation is comparable with the line flux ratio errors. The results indicate that the inclusion of a nebular continuum is very important when fitting the spectral energy distribution as it increases the fluxes of all galaxies. However, there is a mild impact from the inclusion of nebular component analysis in the diagnostic diagrams used to classify the ionisation state of galaxies’ interstellar medium.</p></div></div>","PeriodicalId":479,"journal":{"name":"Astrophysics","volume":"66 3","pages":"311 - 323"},"PeriodicalIF":0.5,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41087387","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}

引用次数: 0

Modified Tsallis Holographic Dark Energy 改进的Tsallis全息暗能量

IF 0.5 4区物理与天体物理

Astrophysics Pub Date : 2023-09-29 DOI: 10.1007/s10511-023-09797-9

J. Bharali, K. Das

引用次数: 0

Motion of a Particle in the Field of an Infinite Flat Slab 粒子在无限平板场中的运动

IF 0.5 4区物理与天体物理

Astrophysics Pub Date : 2023-09-29 DOI: 10.1007/s10511-023-09799-7

R. M. Avagyan, A. A. Saharian, S. S. Jibilyan

引用次数: 0

Swampland Criteria and Neutrino Generation in a Non-Cold Dark Matter Universe Swampland准则与非冷暗物质宇宙中中微子的产生

IF 0.5 4区物理与天体物理

Astrophysics Pub Date : 2023-09-29 DOI: 10.1007/s10511-023-09800-3

M. Khurshudyan

引用次数: 0

Surface Photometry of 50 Dwarf Galaxies in the Local Volume 局域体积中50个矮星系的表面光度测量

IF 0.5 4区物理与天体物理

Astrophysics Pub Date : 2023-09-29 DOI: 10.1007/s10511-023-09791-1

K. A. Kryzhanovsky, M. E. Sharina, I. D. Karachentsev, G. M. Karataeva

引用次数: 0

On a Possible Mechanism for the Start or Resumption of Activity of Radio Galaxies in Clusters of Galaxies 星系团中射电星系活动开始或恢复的可能机制

IF 0.5 4区物理与天体物理

Astrophysics Pub Date : 2023-09-29 DOI: 10.1007/s10511-023-09792-0

R. R. Andreasyan, H. V. Abrahamyan, G. M. Paronyan, G. A. Mikayelyan, A. M. Mickaelian

引用次数: 0

Ephemeris Updates for Seven Selected Hatnet Survey Transiting Exoplanets 七个选定的Hatnet凌日外行星调查的星历更新

IF 0.5 4区物理与天体物理

Astrophysics Pub Date : 2023-09-29 DOI: 10.1007/s10511-023-09794-y

A. Poro, F. A. Farahani, E. Jahangiri, A. Sarostad, M. Gozarandi, M. Haghgou, F. Abolhassani, A. Fakhrabadi, Y. Jongen, A. Wünsche, R Naves, P. Guerra, A. Marchini, M. Salisbury, R. Ehrenberger, V-P. Hentunen

{"title":"Ephemeris Updates for Seven Selected Hatnet Survey Transiting Exoplanets","authors":"A. Poro, F. A. Farahani, E. Jahangiri, A. Sarostad, M. Gozarandi, M. Haghgou, F. Abolhassani, A. Fakhrabadi, Y. Jongen, A. Wünsche, R Naves, P. Guerra, A. Marchini, M. Salisbury, R. Ehrenberger, V-P. Hentunen","doi":"10.1007/s10511-023-09794-y","DOIUrl":"10.1007/s10511-023-09794-y","url":null,"abstract":"<div><div><p>We refined the ephemeris of seven transiting exoplanets HAT-P-6b, HAT-P-12b, HAT-P-18b, HAT-P-22b, HAT-P-32b, HAT-P-33b, and HAT-P-52b. We observed 11 transits from eight observatories in different filters for HAT-P-6b and HAT-P-32b. Also, the Exoplanet Transit Database (ETD) observations for each of the seven exoplanets were analyzed, and the light curves of five systems were studied using Transiting Exoplanet Survey Satellite (TESS) data. We used Exofast-v1 to simulate these ground- and space-based light curves and estimate mid-transit times. We obtained a total of 11, 175 and 67 mid-transit times for these seven exoplanets from our observations, ETD and TESS data, respectively, along with 155 midtransit times from the literature. Then, we generated transit timing variation (TTV) diagrams for each using derived mid-transit times as well as those found in the literature. The systems’ linear ephemeris was then refined and improved using the Markov Chain Monte Carlo (MCMC) method. All of the studied exoplanets, with the exception of the HAT-P-12b system, displayed an increasing trend in the orbital period in the TTV diagrams.</p></div></div>","PeriodicalId":479,"journal":{"name":"Astrophysics","volume":"66 3","pages":"324 - 343"},"PeriodicalIF":0.5,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41087379","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}

引用次数: 0

Renyi Holographic Dark Energy and Its Behaviour in f(G) Gravity 仁义全息暗能量及其在f（G）引力中的行为

IF 0.5 4区物理与天体物理

Astrophysics Pub Date : 2023-09-29 DOI: 10.1007/s10511-023-09798-8

M. K. Alam, S. S. Singh, L. A. Devi

引用次数: 0

Plane Symmetric String Cosmological Model with Zero Mass Scalar Field in f (R) Gravity f（R）引力中具有零质量标量场的平面对称弦宇宙学模型

IF 0.5 4区物理与天体物理

Astrophysics Pub Date : 2023-09-28 DOI: 10.1007/s10511-023-09796-w

Kalpana Pawar, A. K. Dabre, Pallavi Makode

引用次数: 0