So far quite a few ultraluminous X-ray(ULX) pulsars have been discovered.In this work,we construct a super-Eddington,magnetic accretion disk model to estimate the dipole magnetic field of eight ULX pulsars based on th...So far quite a few ultraluminous X-ray(ULX) pulsars have been discovered.In this work,we construct a super-Eddington,magnetic accretion disk model to estimate the dipole magnetic field of eight ULX pulsars based on their observed spin-up variations and luminosities.We obtain two branches of dipole magnetic field solutions.They are distributed in the range of B-(0.156-64.5) × 10^(10) G and-(0.275-79.0) × 10^(13) G corresponding to the low-and high-B solutions respectively.The low magnetic field solutions correspond to the state that the neutron stars are far away from the spin equilibrium,and the high magnetic field solutions are close to the spin equilibrium.The ultra-strong magnetic fields derived in Be-type ULX pulsars imply that the accretion mode in Be-type ULX pulsars could be more complicated than in the persistent ULX pulsars and may not be accounted for by the magnetized accretion disk model.We suggest that the transition between the accretor and the propeller regimes may be used to distinguish between the low-and high-B magnetic field solutions in addition to the detection of the cyclotron resonance scattering features.展开更多
Based on the X-13-ARIMA-SEATS model, aiming at the problem of mobile holidays in China’s economic data, this paper introduces a new method of seasonal adjustment based on the AICC criterion to objectively select the ...Based on the X-13-ARIMA-SEATS model, aiming at the problem of mobile holidays in China’s economic data, this paper introduces a new method of seasonal adjustment based on the AICC criterion to objectively select the parameters of dummy variables of mobile holidays. Taking the current total value of China’s import and export as an example, we expound</span><span style="font-family:""> </span><span style="font-family:Verdana;">a new method for seasonal adjustment of mobile holidays such as Spring Festival, Dragon Boat Festival and Mid-Autumn Festival. Finally, the model is used to predict the total value of China’s import and export in and out of the sample. The prediction results show that the relative error of the out of sample data is less than 5%. The new method has advantages in the processing of macroeconomic data.展开更多
基金supported by the National Key Research and Development Program of China (2016YFA0400803)the National Natural Science Foundation of China under grant Nos.11773015 and 10241301Project U1838201 supported by NSFC and CAS。
文摘So far quite a few ultraluminous X-ray(ULX) pulsars have been discovered.In this work,we construct a super-Eddington,magnetic accretion disk model to estimate the dipole magnetic field of eight ULX pulsars based on their observed spin-up variations and luminosities.We obtain two branches of dipole magnetic field solutions.They are distributed in the range of B-(0.156-64.5) × 10^(10) G and-(0.275-79.0) × 10^(13) G corresponding to the low-and high-B solutions respectively.The low magnetic field solutions correspond to the state that the neutron stars are far away from the spin equilibrium,and the high magnetic field solutions are close to the spin equilibrium.The ultra-strong magnetic fields derived in Be-type ULX pulsars imply that the accretion mode in Be-type ULX pulsars could be more complicated than in the persistent ULX pulsars and may not be accounted for by the magnetized accretion disk model.We suggest that the transition between the accretor and the propeller regimes may be used to distinguish between the low-and high-B magnetic field solutions in addition to the detection of the cyclotron resonance scattering features.
文摘Based on the X-13-ARIMA-SEATS model, aiming at the problem of mobile holidays in China’s economic data, this paper introduces a new method of seasonal adjustment based on the AICC criterion to objectively select the parameters of dummy variables of mobile holidays. Taking the current total value of China’s import and export as an example, we expound</span><span style="font-family:""> </span><span style="font-family:Verdana;">a new method for seasonal adjustment of mobile holidays such as Spring Festival, Dragon Boat Festival and Mid-Autumn Festival. Finally, the model is used to predict the total value of China’s import and export in and out of the sample. The prediction results show that the relative error of the out of sample data is less than 5%. The new method has advantages in the processing of macroeconomic data.
