作者机构：
[Yu, Yun-Wei; Zheng, Xiao-Ping; Du, Ze-Xin; Yu, YW] Cent China Normal Univ, Inst Astrophys, Wuhan 430079, Peoples R China.;[Yu, Yun-Wei; Zheng, Xiao-Ping; Yu, YW] Cent China Normal Univ, Key Lab Quark & Lepton Phys, Minist Educ, Wuhan 430079, Peoples R China.;[Chen, A-Ming] Shanghai Jiao Tong Univ, Tsung Dao Lee Inst, Shanghai 201210, Peoples R China.;[Zhou, Xia; Wang, Shuang-Qiang] Chinese Acad Sci, Xinjiang Astron Observ, Urumqi 830011, Peoples R China.;[Zhou, Xia] Chinese Acad Sci, Key Lab Radio Astron, Nanjing 210008, Peoples R China.
通讯机构：
[Yu, YW ] C;Cent China Normal Univ, Inst Astrophys, Wuhan 430079, Peoples R China.;Cent China Normal Univ, Key Lab Quark & Lepton Phys, Minist Educ, Wuhan 430079, Peoples R China.
摘要：
<jats:title>Abstract</jats:title>
<jats:p>Black widows (BWs) are millisecond pulsars ablating their companion stars. The out-flowing material from the companion can block the radio emission of the pulsar, resulting in eclipses. In this paper, we construct a model for the radio eclipse by calculating the geometry of the bow shock between the winds of the pulsar and companion, where the shock shapes the eclipsing medium but had not been described in detail in previous works. The model is further used to explain the variations of the flux density and dispersion measure of three BW pulsars (i.e., PSR B1957+20, J2055+3829, and J2051−0827) detected by the Five-hundred-meter Aperture Spherical radio Telescope. Consequently, we constrained the parameters of the three BW systems such as the inclination angles and true anomalies of the observer as well as the mass-loss rates and wind velocity of the companion stars. With the help of these constraints, it is expected that magnetic fields of companion stars and even masses of pulsars could further be determined as some extra observation can be achieved in the future.</jats:p>
