An investigation on the possible dynamical models of the core galaxy NGC 1399 is performed.Because early-type galaxies are likely to be formed through merging events, remnant rings are considered in the modeling proce...An investigation on the possible dynamical models of the core galaxy NGC 1399 is performed.Because early-type galaxies are likely to be formed through merging events, remnant rings are considered in the modeling process.A numerical survey over three parameters is employed to obtain the best-fit models that are completely consistent with observations.It is found that the inner slope of the dark matter profile is cuspy for this core galaxy.The existence of remnant rings in best-fit models indicates a merging history.The remnant ring explains the flattened surface brightness and thus could be the physical counterpart of the core structure of NGC 1399.展开更多
Considering the importance of investigating the transit timing variations(TTVs)of transiting exoplanets,we present a follow-up study of HAT-P-12 b.We include six new light curves observed between2011 and 2015 from thr...Considering the importance of investigating the transit timing variations(TTVs)of transiting exoplanets,we present a follow-up study of HAT-P-12 b.We include six new light curves observed between2011 and 2015 from three different observatories,in association with 25 light curves taken from the published literature.The sample of the data used thus covers a time span of~10.2 years with a large coverage of epochs(1160)for the transiting events of the exoplanet HAT-P-12 b.The light curves are utilized to determine the orbital parameters and conduct an investigation of possible TTVs.The new linear ephemeris shows a large value of reducedχ^(2),i.e.X_(red)^(2)(23)=7.93,and the sinusoidal fitting using the prominent frequency coming from a periodogram shows a reducedχ^(2) around 4.Based on these values and the corresponding O-C diagrams,we suspect the presence of a possible non-sinusoidal TTV in this planetary system.Finally,we find that a scenario with an additional non-transiting exoplanet could explain this TTV with an even smaller reducedχ^(2) value of around 2.展开更多
基金supported in part by the Ministry of Science and Technology, Taiwan, under Li-Chin Yeh’s Grant MOST 106-2115-M-007-014Ing-Guey Jiang’s Grant MOST 106-2112-M-007-006-MY3
文摘An investigation on the possible dynamical models of the core galaxy NGC 1399 is performed.Because early-type galaxies are likely to be formed through merging events, remnant rings are considered in the modeling process.A numerical survey over three parameters is employed to obtain the best-fit models that are completely consistent with observations.It is found that the inner slope of the dark matter profile is cuspy for this core galaxy.The existence of remnant rings in best-fit models indicates a merging history.The remnant ring explains the flattened surface brightness and thus could be the physical counterpart of the core structure of NGC 1399.
基金supported by grants from the Ministry of Science and Technology(MOST),Taiwan,China.The grant numbers are MOST 105-2119-M-007-029-MY3,MOST 1062112-M-007-006-MY3the University Grants Commission(UGC)+6 种基金financial support through Major Research Project no.UGC-MRP 43-521/2014(SR)IUCCA,Pune,India for providing supports through the IUCCA Associateship Programmefinancially supported by the National Natural Science Foundation of China(Grant Nos.11590782 and 11421303)supported by the B-type Strategic Priority Program of the Chinese Academy of Sciences(Grant No.XDB41000000)the National Natural Science Foundation of China(Grant No.11773081)CAS Interdisciplinary Innovation TeamFoundation of Minor Planets of the Purple Mountain Observatory。
文摘Considering the importance of investigating the transit timing variations(TTVs)of transiting exoplanets,we present a follow-up study of HAT-P-12 b.We include six new light curves observed between2011 and 2015 from three different observatories,in association with 25 light curves taken from the published literature.The sample of the data used thus covers a time span of~10.2 years with a large coverage of epochs(1160)for the transiting events of the exoplanet HAT-P-12 b.The light curves are utilized to determine the orbital parameters and conduct an investigation of possible TTVs.The new linear ephemeris shows a large value of reducedχ^(2),i.e.X_(red)^(2)(23)=7.93,and the sinusoidal fitting using the prominent frequency coming from a periodogram shows a reducedχ^(2) around 4.Based on these values and the corresponding O-C diagrams,we suspect the presence of a possible non-sinusoidal TTV in this planetary system.Finally,we find that a scenario with an additional non-transiting exoplanet could explain this TTV with an even smaller reducedχ^(2) value of around 2.
