|
The emission mechanism from X-ray soturces in close binary stars is studied.It is suggested that pair production may play an important role in the X-ray emission region which is formed by the accretion of a compact object(a neutron star or a black hole).The present model accounts qualitatively for the following observed general properties in X-ray binaries: 1.The X-ray luminosity lies within the range 10~(36)—10~(38)erg/sec. 2.The X-ray energy spectrum can in the majority of cases be represented either the power-law... The emission mechanism from X-ray soturces in close binary stars is studied.It is suggested that pair production may play an important role in the X-ray emission region which is formed by the accretion of a compact object(a neutron star or a black hole).The present model accounts qualitatively for the following observed general properties in X-ray binaries: 1.The X-ray luminosity lies within the range 10~(36)—10~(38)erg/sec. 2.The X-ray energy spectrum can in the majority of cases be represented either the power-law or the thermal bremsstrahlung form. 3.The temperature of the thermal bremsstrahlung spectrum is the order of 10~8K. 4.The form of the energy spectrum does not change appreciably when the luminosity fluctuates. 本文研究了密近双星中的 X 射线源的发射机制.本文提出:在致密星(中子星或黑洞)的吸积所形成的 X 射线发射区中,电子对的产生起着重要的作用.这种模型可以定性地说明 X射线双星所具有的几个一般的观测特征,即:1.它们的 X 射线光度都在10~(36)—10~(38)尔格/秒范围中.2.X 射线能谱为幂形式,或热韧致形式.3.热韧致谱的温度数量级为10~K.4.当光度涨落时,能谱形式无明显变化. In this paper, we shall show that a star model, which is black hole-free and singu-larity-free, can be obtained naturally in the gravitational guage theory, provided the space- time is torsion-free and the matter is spinless. Our conclusions in a sense show that he discussions about the black hole and the singularity based on the general relativity may not describe the nature correctly. 本文得出,在时空无挠率、物质无自旋的条件下,从重力规范理论出发,可以建立某种既非黑洞又无奇性的星体模型。这样,本文就在一定意义上表明,以广义相对论为基础对黑洞和奇性的讨论,很可能并不符合自然界的真实情况。 Eecently, Liu and Xu studied the Hawking evaporation of the Dirac particles out of the quasi-extreme Kerr black holes on the foundation of the S. Chandrasekhar 's work. In this paper, Liu and Xu's work is firstly extended to the quasi-extreme Kerr-Newman black holes, and then to general Kerr-Newman black holes. The Hawking thermal spectrum for fermions for general Kerr-Newman black holes is obtained.The Dirac equation in the spinor form of the charged particles in the Kerr-Newman spacetime was given by Page:... Eecently, Liu and Xu studied the Hawking evaporation of the Dirac particles out of the quasi-extreme Kerr black holes on the foundation of the S. Chandrasekhar 's work. In this paper, Liu and Xu's work is firstly extended to the quasi-extreme Kerr-Newman black holes, and then to general Kerr-Newman black holes. The Hawking thermal spectrum for fermions for general Kerr-Newman black holes is obtained.The Dirac equation in the spinor form of the charged particles in the Kerr-Newman spacetime was given by Page: (in this paper G= h =C=I)By means of null-tetrad and dyad, we have obtained the uncoupled Dirac equations, thatIntroducing '' Tortoise coordinates transformation''near the horizons, we haveFor the quasi-extreme Kerr-Newman black holes, we obtainwhereK = (r2 + a2)ω- am- eQr. The solutions of Eq. (6) arewith Just outside the horizon, we have the outgoing waves withNow, we would exter of it. We can only e complex plane. We the radius |r-r+|. SThe outgoing waves inside and outside the horizon can be written together as whereOutside the horizon, Eq. (9) represents an outgoing positive-energy flux of particles coming from the horizon. But inside the horizon, Eq. (9) describes a positive-energy flux of particles traveling backward in time out of the singularity. In other words, it describes a negative-energy flux of antiparticles traveling forward in time for the singularity. It means that particle-antiparticle pairs are created near the horizon.Apparently, from the normalization condition, we can obtain thatorwithwhere T is the temperature of the black hole, k is the Boltzmann constant, and k is the gravitational acceleration of the horizon. Eq. (10) is the Hawking thermal spectrum formula about Dirac particles for the quasi-extreme Kerr-Newman black holes.On the other hand, the outgoing waves solutions of the Dirac equation for the quasi-extreme Kerr-Newman black holes are also the outgoing waves solutions of the Klein-Gordon equation for general Kerr-Newman black holes. And we find these outgoing waves solutions satisfy the Dirac equation (5) for general Kerr-Newman black holes too. So, we can obtain the same Hawking thermal spectrum for fermions from the Dirac equation as from the Klein-Gordon equation for all of the Kerr-Newman black holes. 本文得到了Kerr-Newman黑洞视界附近Dirac方程的解,并与Klein-Gordon方程的解作了比较。把刘辽、许殿彦的工作首先从准极端Kerr黑洞推广到准极端Kerr-Newman黑洞,然后又进一步推广到一般Kerr-Newman黑洞,从而证实了一般Kerr-Newman黑洞辐射的Dirac粒子的能谱具有黑体辐射的形式。
|