The Full-disk vector Magneto Graph(FMG)instrument will carry out polarization observations at one wavelength position of the Fe I 5324.179?spectral line.This paper describes how to choose this single wavelength positi...The Full-disk vector Magneto Graph(FMG)instrument will carry out polarization observations at one wavelength position of the Fe I 5324.179?spectral line.This paper describes how to choose this single wavelength position,the relevant data-processing and the magnetic field calibrations based on the measured polarization signals at one single wavelength position.It is found that solar radial Doppler velocity,which can cause the spectral line to shift,is a disadvantageous factor for the linear calibration at one wavelength position.Observations at two symmetric wavelength positions may significantly reduce the wavelength shift effect(~75%),but simulations show that such polarization signals located at the solar limbs(e.g.,beyond the longitude range of±30°)are not free from the effect completely.In future work,we plan to apply machine learning techniques to calibrate vector magnetic fields,or employ full Stokes parameter profile inversion techniques to obtain accurate vector magnetic fields,in order to complement the linear calibration at the single wavelength position.展开更多
We observed a C-class flare at the outer boundary of the superpenumbra of a sunspot. The flare was triggered by an emerging magnetic bipolar region that was obliquely oriented with respect to the superpenumbral fibril...We observed a C-class flare at the outer boundary of the superpenumbra of a sunspot. The flare was triggered by an emerging magnetic bipolar region that was obliquely oriented with respect to the superpenumbral fibrils. The flare started due to the low height magnetic reconnection of emerging magnetic flux with a superpenumbral field resulting in hot multi-temperature plasma flows in the inverse Evershed flow channel and its overlying atmosphere. Inverse Evershed flows in the chromosphere start from the superpenumbra towards the sunspot that end at the outer boundary of the penumbra. The hot plasma flow towards the sunspot in the inverse Evershed channels show about 10 km s^-1 higher velocity in Ha wavelengths compared to the plasma emissions at various temperatures as seen in different AIA filters. Even though these velocities are about seven times higher than the typical inverse Evershed flow speeds, the flow is diminished at the outer boundary of the sunspot＇s penumbra. This suggests that the superpenumbral field lines that carry inverse Evershed flows are discontinued at the boundary where the penumbral field lines dive into the sun and these two sets of field lines are completely distinct. The discontinuity in the typical magnetic field and plasma properties at the adjoining of these two sets of field lines further leads to discontinuity in the characteristic magnetoacoustic and Alfvrn speeds, thereby stopping the plasma flows further on. The multi-temperature plasma in the inverse Evershed channels exhibits possible longitudinal oscillations initially during the onset of the flare, and later flows towards the sunspot. In the multi-temperature view, the different layers above the flare region have a mixture of supersonic as well as subsonic flows.展开更多
A longitudinal magnetic field often suffers the saturation effect in a strong magnetic field region when the measurement is performed at a single-wavelength point and linear calibration is adopted.In this study,we dev...A longitudinal magnetic field often suffers the saturation effect in a strong magnetic field region when the measurement is performed at a single-wavelength point and linear calibration is adopted.In this study,we develop a method that can judge the threshold of saturation in Stokes V/I observed by the Solar Magnetic Field Telescope(SMFT)and correct it automatically.The procedure is to first perform the second-order polynomial fit to the Stokes V/I vs.I/I_(m)(I_(m) is the maximum value of Stokes I)curve to estimate the threshold of saturation,then reconstruct Stokes V/I in a strong field region to correct for saturation.The algorithm is demonstrated to be effective by comparing with the magnetograms obtained by the Helioseismic and Magnetic Imager(HMI).The accuracy rate of detection and correction for saturation is~99.4%and~88%respectively among 175 active regions.The advantages and disadvantages of the algorithm are discussed.展开更多
Antibiotic resistance genes comprising antibiotic resistome are of great concern due to their increase in the environment.Recent evidence of shared resistomes between soils and animal husbandry has imposed potential r...Antibiotic resistance genes comprising antibiotic resistome are of great concern due to their increase in the environment.Recent evidence of shared resistomes between soils and animal husbandry has imposed potential risks to human health.However,the correlation between a given community’s resistome and bacterial taxonomic composition is controversial.Here,a transmission chain of resistomes from swine manure to compost and compost-amended soil were analyzed in five suburban areas of Beijing,China,with unamended agricultural soils as control soils.Antibiotic resistomes and bacterial taxonomic compositions were distinct between(I)manure and compost;and(II)compost-amended and control soils.In manure,compost,and compost-amended soils,theβ-diversity of the resistome and bacterial taxonomic composition was significantly correlated,while no correlation was detected in control soils.Bacterial taxonomic composition explained 36.0%of total variations of the resistome composition,much higher than environmental factors.Together,those results demonstrated that antibiotic resistome was closely related to bacterial taxonomic composition along the suburban transmission chain.展开更多
基金supported by the Strategic Priority Research Program on Space Science, the Chinese Academy of Sciences (Grant Nos. XDA15320302, XDA15052200 and XDA15320102)the National Natural Science Foundation of China (Grant Nos. 11773038, 11703042, U1731241, 11427901, 11427803, 11473039 and U1831107)the 13th Fiveyear Informatization Plan of the Chinese Academy of Sciences (Grant No. XXH13505-04)
文摘The Full-disk vector Magneto Graph(FMG)instrument will carry out polarization observations at one wavelength position of the Fe I 5324.179?spectral line.This paper describes how to choose this single wavelength position,the relevant data-processing and the magnetic field calibrations based on the measured polarization signals at one single wavelength position.It is found that solar radial Doppler velocity,which can cause the spectral line to shift,is a disadvantageous factor for the linear calibration at one wavelength position.Observations at two symmetric wavelength positions may significantly reduce the wavelength shift effect(~75%),but simulations show that such polarization signals located at the solar limbs(e.g.,beyond the longitude range of±30°)are not free from the effect completely.In future work,we plan to apply machine learning techniques to calibrate vector magnetic fields,or employ full Stokes parameter profile inversion techniques to obtain accurate vector magnetic fields,in order to complement the linear calibration at the single wavelength position.
基金the Chinese Academy of Sciences to NAOCfunded by the Chinese Academy of Science President’s International Fellowship Initiative
文摘We observed a C-class flare at the outer boundary of the superpenumbra of a sunspot. The flare was triggered by an emerging magnetic bipolar region that was obliquely oriented with respect to the superpenumbral fibrils. The flare started due to the low height magnetic reconnection of emerging magnetic flux with a superpenumbral field resulting in hot multi-temperature plasma flows in the inverse Evershed flow channel and its overlying atmosphere. Inverse Evershed flows in the chromosphere start from the superpenumbra towards the sunspot that end at the outer boundary of the penumbra. The hot plasma flow towards the sunspot in the inverse Evershed channels show about 10 km s^-1 higher velocity in Ha wavelengths compared to the plasma emissions at various temperatures as seen in different AIA filters. Even though these velocities are about seven times higher than the typical inverse Evershed flow speeds, the flow is diminished at the outer boundary of the sunspot＇s penumbra. This suggests that the superpenumbral field lines that carry inverse Evershed flows are discontinued at the boundary where the penumbral field lines dive into the sun and these two sets of field lines are completely distinct. The discontinuity in the typical magnetic field and plasma properties at the adjoining of these two sets of field lines further leads to discontinuity in the characteristic magnetoacoustic and Alfvrn speeds, thereby stopping the plasma flows further on. The multi-temperature plasma in the inverse Evershed channels exhibits possible longitudinal oscillations initially during the onset of the flare, and later flows towards the sunspot. In the multi-temperature view, the different layers above the flare region have a mixture of supersonic as well as subsonic flows.
基金supported by the National Natural Science Foundation of China(Grant Nos.11703042,11911530089,U1731241,11773038,11427901,11427803,11673033,U1831107,11873062)the Strategic Priority Research Program on Space Science+1 种基金Chinese Academy of Sciences(Grant Nos.XDA15320302,XDA15052200,XDA15320102)the13th Five-year Informatization Plan of Chinese Academy of Sciences(Grant No.XXH13505–04)。
文摘A longitudinal magnetic field often suffers the saturation effect in a strong magnetic field region when the measurement is performed at a single-wavelength point and linear calibration is adopted.In this study,we develop a method that can judge the threshold of saturation in Stokes V/I observed by the Solar Magnetic Field Telescope(SMFT)and correct it automatically.The procedure is to first perform the second-order polynomial fit to the Stokes V/I vs.I/I_(m)(I_(m) is the maximum value of Stokes I)curve to estimate the threshold of saturation,then reconstruct Stokes V/I in a strong field region to correct for saturation.The algorithm is demonstrated to be effective by comparing with the magnetograms obtained by the Helioseismic and Magnetic Imager(HMI).The accuracy rate of detection and correction for saturation is~99.4%and~88%respectively among 175 active regions.The advantages and disadvantages of the algorithm are discussed.
基金sponsored by the National Key R&D Program of China(No.2019YFC1806204)the National Natural Science Foundation of China(Grant Nos.41825016,41430856).
文摘Antibiotic resistance genes comprising antibiotic resistome are of great concern due to their increase in the environment.Recent evidence of shared resistomes between soils and animal husbandry has imposed potential risks to human health.However,the correlation between a given community’s resistome and bacterial taxonomic composition is controversial.Here,a transmission chain of resistomes from swine manure to compost and compost-amended soil were analyzed in five suburban areas of Beijing,China,with unamended agricultural soils as control soils.Antibiotic resistomes and bacterial taxonomic compositions were distinct between(I)manure and compost;and(II)compost-amended and control soils.In manure,compost,and compost-amended soils,theβ-diversity of the resistome and bacterial taxonomic composition was significantly correlated,while no correlation was detected in control soils.Bacterial taxonomic composition explained 36.0%of total variations of the resistome composition,much higher than environmental factors.Together,those results demonstrated that antibiotic resistome was closely related to bacterial taxonomic composition along the suburban transmission chain.
