z = 2 - 4时七个GRB宿主半导体中的高离子吸收：环爆等离子体和流出星际气体的证据
High-Ion Absorption in Seven GRB Host Galaxies at z=2-4: Evidence for both Circumburst Plasma and Outflowing Interstellar Gas
摘要：
利用VLT/UVES高分辨光谱技术对7个z_GRB> 2的GRB余辉进行了研究。我们的样品由GRB 021004、050730、050820、050922C、060607、071031和080310组成。其中四个光谱是在快速响应模式下拍摄的，在雨燕伽玛射线暴探测的30分钟内。我们确定了几个不同类别的高离子吸收速度接近z_GRB：（i）强的高离子成分在z_GRB本身总是看到OVI，CIV，和SiIV，通常（在6 7例）在NV。我们讨论了这种吸收的起源环暴和星际模型。使用非检测SIV * 对GRB 050730与紫外光激发模型，我们把一个下限为400 pc的距离SIV轴承气体从GRB。(ii)在每个光谱中观察到z_GRB周围100 - 400 km/s的复杂的多分量CIV和SiIV剖面;这些速度场与在类似红移的阻尼Lyman-α系统中测量的速度场相似，表明星系起源。(iii)在CIV、SiIV和OVI剖面中，在7个光谱中的4个中，可以看到覆盖65 - 140 km/s的不对称蓝移吸收线机翼。机翼的运动学与观察，两个翅膀显示“银河系”的CIV/SiIV比表明这些功能跟踪流出的ISM气体在伽玛射线暴的宿主星系。(iv)高速（HV; 500 - 5000公里/秒）的组件中检测到的7个光谱。HV组件显示不同的属性。在伽玛暴071031和080310的情况下，电离水平（非常高的CIV/SiIV比和中性相吸收的情况下）和HV组件的运动学可以解释从伽玛暴祖先的沃尔夫-拉叶风。
英文摘要：
(Abridged) We use VLT/UVES high-resolution optical spectroscopy of seven GRB afterglows at z_GRB>2 to investigate circumburst and interstellar plasma in the host galaxies. Our sample consists of GRBs 021004, 050730, 050820, 050922C, 060607, 071031, and 080310. Four of these spectra were taken in rapid-response mode, within 30 minutes of the Swift GRB detection. We identify several distinct categories of high-ion absorption at velocities close to z_GRB: (i) Strong high-ion components at z_GRB itself are always seen in OVI, CIV, and SiIV, and usually (in 6 of 7 cases) in NV. We discuss circumburst and interstellar models for the origin of this absorption. Using the non-detection of SIV* toward GRB 050730 together with a UV photo-excitation model, we place a lower limit of 400 pc on the distance of the SIV-bearing gas from the GRB. (ii) Complex, multi-component CIV and SiIV profiles extending over 100-400 km/s around z_GRB are observed in each spectrum; these velocity fields are similar to those measured in damped Lyman-alpha systems at similar redshifts, suggesting a galactic origin. (iii) Asymmetric, blueshifted, absorption-line wings covering 65-140 km/s are seen in the CIV, SiIV, and OVI profiles in 4 of the 7 spectra. The wing kinematics together with the observation that two wings show "Galactic" CIV/SiIV ratios suggest these features trace outflowing ISM gas in the GRB host galaxies. (iv) High-velocity (HV; 500-5000 km/s) components are detected in 6 of the 7 spectra. The HV components show diverse properties. In the cases of GRBs 071031 and 080310, both the ionization level (very high CIV/SiIV ratios and absence of neutral-phase absorption) and the kinematics of the HV components can be explained by Wolf-Rayet winds from the GRB progenitors.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
