Using multi-band photometric images of M51 and its companion NGC 5195 from ultraviolet to optical and infrared,we investigate spatially resolved stellar population properties of this interacting system with stellar po...Using multi-band photometric images of M51 and its companion NGC 5195 from ultraviolet to optical and infrared,we investigate spatially resolved stellar population properties of this interacting system with stellar population synthesis models.The observed infrared excess(IRX)is used to constrain dust extinction.Stellar mass is also inferred from the model fitting.By fitting observed spectral energy distributions(SEDs)with synthetical ones,we derive two-dimensional distributions of stellar age,metallicity,dust extinction and stellar mass.In M51,two grand-designed spiral arms extending from the bulge show young age,rich metallicity and abundant dust.The inter-arm regions are filled with older,metalpoorer and less dusty stellar populations.Except for the spiral arm extending from M51 into NGC 5195,the stellar population properties of NGC 5195 are quite featureless.NGC 5195 is much older than M51,and its core is very dusty with AV up to 1.67 mag and dense in stellar mass surface density.The close encounters might drive the dust in the spiral arm of M51 into the center of NGC 5195.展开更多
We present an analysis of the diffuse soft X-ray emission from the nuclear region of M51 combining both XMM-Newton RGS and Chandra data.Most of the RGS spectrum of M51 can be fitted with a thermal model with a tempera...We present an analysis of the diffuse soft X-ray emission from the nuclear region of M51 combining both XMM-Newton RGS and Chandra data.Most of the RGS spectrum of M51 can be fitted with a thermal model with a temperature of^0.5 ke V except for the O VII triplet,which is forbidden-line dominated.The Fe L-shell lines peak around the southern cloud,where the O VIII and N VII Lyαlines also peak.In contrast,the peak of the O VII forbidden line is about 10′′offset from that of the other lines,indicating that it is from a spatially distinct component.The spatial distribution of the O VII triplet mapped by the Chandra data shows that most of the O VII triplet flux is located at faint regions near edges,instead of the southern cloud where other lines peak.This distribution of the O VII triplet is inconsistent with the photoionization model.Other mechanisms that could produce the anomalous O VII triplet,including a recombining plasma and charge exchange X-ray emission,are discussed.展开更多
The particle paths of the Lagrangian flow field between two cylinders simulate well the spiral arms of GalaxyM51 image [1] and the interface curve of the Yin-Yang balance in the ancient Tai-Chi diagram [2]. The partic...The particle paths of the Lagrangian flow field between two cylinders simulate well the spiral arms of GalaxyM51 image [1] and the interface curve of the Yin-Yang balance in the ancient Tai-Chi diagram [2]. The particlepaths of the Lagrangian flow field involve four parameters. The normalization of the system of equations significantlysimplifies the formulation of the flow process and reduces the original four parameters to only one parameter.Furthermore it provides the similarity between the formulation of the spiral arms of Galaxy M51 and thatof the interface curve of the Yin-Yang balance in the ancient Tai-Chi diagram.展开更多
According to some fundamental hypotheses compatible with microphysics theory in allusion to property of graviton shot by the spiral galaxy, we set up a motion trace equation of graviton in the three-dimensional space,...According to some fundamental hypotheses compatible with microphysics theory in allusion to property of graviton shot by the spiral galaxy, we set up a motion trace equation of graviton in the three-dimensional space, concluding method for measuring the velocity of graviton. This theory reveals formation mechanism of symmetric rotating arm image of the spiral galaxy. The rotating arm image conforms to Archimedes spiral. Under the condition of using dynamic constraints, the image that astrolabe is in thin-disk structure is naturally obtained. And then, we also deduce the law that astrolabe thickness h is inversely proportional to the square root of the distance rxy between astrolabe and galaxy center, according with actual crossrange galaxy observation image excellently. This article, by utilizing several typical galaxy observation images with completely different appearances and shapes, verifies the motion trace law of graviton in three-dimensional space. And the theoretical simulation data meet observation image data very well. As per the discovery in the simulation of three-dimensional theoretical model, changes of parameters in theoretical model will exert a great influence on the shape of galaxy. This theory owns exclusively important meaning, not only to astrophysics, but also to reconstruction and development of relativity theory and the whole basic physics theory, as well as breaking through the current dilemma in studying graviton property.展开更多
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
According to a series of hypothesis, for the spiral galaxy, a mathematical equation of the graviton movement track is built, it is also the central curve of the nebulae density distribution, which offers the method to...According to a series of hypothesis, for the spiral galaxy, a mathematical equation of the graviton movement track is built, it is also the central curve of the nebulae density distribution, which offers the method to measure the moving speed of the graviton. Using the observed images of the M51 galaxy, it confirms that the graviton movement curve in the spiral galaxy conforms to the image, QUOTE QUOTEis a constant. It points out that by measuring the rate of angular motion of the equivalent center in the galaxy, the real speed of the graviton can be estimated. Under the measuring condition of the M51,. The theory presented in this article also helps to calculate the rotation speed of a galaxy, provided the graviton speed is known for certain. With the model in this article and fitting data from the observation images of M51 galaxy, the guess which says “the moving speed of graviton is a constant” is supported unprecedentedly by observation data. It is for the first time that the upper limit of graviton speed, i.e. no more than times of light speed, is obtained from observation data. At the same time, the paper puts forward one possible way that the lower limit of graviton speed may be measured. And a new idea also brought forward in the paper is that the rotational angular velocity w of the equivalent center which plays an important role in a spiral galaxy may be measured according to the observed data of the thickness of galactic center of the spiral galaxy.展开更多
基金Major Program of National Natural Science Foundation of China(No.11890691)supported by the National Basic Research Program of China(973 Program+6 种基金Grant No.2017YFA0402600)the National Natural Science Foundation of China(NSFCGrant Nos.11433005,11673027,11733007,11973038,11320101002 and 11421303)the External Cooperation Program of Chinese Academy of Sciences(Grant No.114A11KYSB20160057)the Two Micron All Sky Survey,which is a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center/California Institute of Technology,funded by the National Aeronautics and Space Administration and the National Science Foundationa key project of the Telescope Access Program(TAP),which has been funded by National Astronomical Observatories,Chinese Academy of Sciences(the Strategic Priority Research Program“The Emergence of Cosmological Structures”grant No.XDB09000000)the Special Fund for Astronomy from the Ministry of Finance。
文摘Using multi-band photometric images of M51 and its companion NGC 5195 from ultraviolet to optical and infrared,we investigate spatially resolved stellar population properties of this interacting system with stellar population synthesis models.The observed infrared excess(IRX)is used to constrain dust extinction.Stellar mass is also inferred from the model fitting.By fitting observed spectral energy distributions(SEDs)with synthetical ones,we derive two-dimensional distributions of stellar age,metallicity,dust extinction and stellar mass.In M51,two grand-designed spiral arms extending from the bulge show young age,rich metallicity and abundant dust.The inter-arm regions are filled with older,metalpoorer and less dusty stellar populations.Except for the spiral arm extending from M51 into NGC 5195,the stellar population properties of NGC 5195 are quite featureless.NGC 5195 is much older than M51,and its core is very dusty with AV up to 1.67 mag and dense in stellar mass surface density.The close encounters might drive the dust in the spiral arm of M51 into the center of NGC 5195.
基金supported by a National Natural Science Foundation of China for Young Scholar Grant (11203032)the Strategic Priority Research Program"The Emergence of Cosmological Structures" of the Chinese Academy of Sciences Grant No.XDB09000000NSFC grant 11333003 (SM)
文摘We present an analysis of the diffuse soft X-ray emission from the nuclear region of M51 combining both XMM-Newton RGS and Chandra data.Most of the RGS spectrum of M51 can be fitted with a thermal model with a temperature of^0.5 ke V except for the O VII triplet,which is forbidden-line dominated.The Fe L-shell lines peak around the southern cloud,where the O VIII and N VII Lyαlines also peak.In contrast,the peak of the O VII forbidden line is about 10′′offset from that of the other lines,indicating that it is from a spatially distinct component.The spatial distribution of the O VII triplet mapped by the Chandra data shows that most of the O VII triplet flux is located at faint regions near edges,instead of the southern cloud where other lines peak.This distribution of the O VII triplet is inconsistent with the photoionization model.Other mechanisms that could produce the anomalous O VII triplet,including a recombining plasma and charge exchange X-ray emission,are discussed.
基金sponsored by the Natural SciencesEngineering Research Council of Canada
文摘The particle paths of the Lagrangian flow field between two cylinders simulate well the spiral arms of GalaxyM51 image [1] and the interface curve of the Yin-Yang balance in the ancient Tai-Chi diagram [2]. The particlepaths of the Lagrangian flow field involve four parameters. The normalization of the system of equations significantlysimplifies the formulation of the flow process and reduces the original four parameters to only one parameter.Furthermore it provides the similarity between the formulation of the spiral arms of Galaxy M51 and thatof the interface curve of the Yin-Yang balance in the ancient Tai-Chi diagram.
文摘According to some fundamental hypotheses compatible with microphysics theory in allusion to property of graviton shot by the spiral galaxy, we set up a motion trace equation of graviton in the three-dimensional space, concluding method for measuring the velocity of graviton. This theory reveals formation mechanism of symmetric rotating arm image of the spiral galaxy. The rotating arm image conforms to Archimedes spiral. Under the condition of using dynamic constraints, the image that astrolabe is in thin-disk structure is naturally obtained. And then, we also deduce the law that astrolabe thickness h is inversely proportional to the square root of the distance rxy between astrolabe and galaxy center, according with actual crossrange galaxy observation image excellently. This article, by utilizing several typical galaxy observation images with completely different appearances and shapes, verifies the motion trace law of graviton in three-dimensional space. And the theoretical simulation data meet observation image data very well. As per the discovery in the simulation of three-dimensional theoretical model, changes of parameters in theoretical model will exert a great influence on the shape of galaxy. This theory owns exclusively important meaning, not only to astrophysics, but also to reconstruction and development of relativity theory and the whole basic physics theory, as well as breaking through the current dilemma in studying graviton property.
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According to a series of hypothesis, for the spiral galaxy, a mathematical equation of the graviton movement track is built, it is also the central curve of the nebulae density distribution, which offers the method to measure the moving speed of the graviton. Using the observed images of the M51 galaxy, it confirms that the graviton movement curve in the spiral galaxy conforms to the image, QUOTE QUOTEis a constant. It points out that by measuring the rate of angular motion of the equivalent center in the galaxy, the real speed of the graviton can be estimated. Under the measuring condition of the M51,. The theory presented in this article also helps to calculate the rotation speed of a galaxy, provided the graviton speed is known for certain. With the model in this article and fitting data from the observation images of M51 galaxy, the guess which says “the moving speed of graviton is a constant” is supported unprecedentedly by observation data. It is for the first time that the upper limit of graviton speed, i.e. no more than times of light speed, is obtained from observation data. At the same time, the paper puts forward one possible way that the lower limit of graviton speed may be measured. And a new idea also brought forward in the paper is that the rotational angular velocity w of the equivalent center which plays an important role in a spiral galaxy may be measured according to the observed data of the thickness of galactic center of the spiral galaxy.
