GMRT and VLA observations of HI AND OH from the Seyfert galaxy MRK 1
GMRT and VLA observations of HI AND OH from the Seyfert galaxy MRK 1
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来自塞弗特星系 MRK 1 的 HI 和 OH 的 GMRT 和 VLA 观测
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发表时间：
2002
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通讯作者：
Usa
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作者：
A. Omar;K. Dwarakanath;M. Rupen;K. Institute;Bangalore;India. National Radio Astronomy Observatory;Socorro;Usa
我们目前的巨米波射电望远镜（GMRT）的观测的Hi 21厘米线和甚大阵（VLA）的观测OH 18厘米线从塞弗特2星系Mrk 1。在Mrk 1和它的伴星NGC 451中都探测到了Hi辐射。Mrk 1的Hi发射形态和速度场受到干扰。我们推测Mrk 1的核活动是由潮汐相互作用触发的。我们估计Mrk 1和NGC 451的Hi质量分别为8：0（0：6）10 8 M和1：3（0：1）10 9 M。我们还检测到的Hi 21厘米线和OH 18厘米线的吸收朝向核的Mrk 1在蓝移的速度相对于其系统的速度表示流出的原子和分子气体。在1665和1667 MHz处检测到两条OH线。每个配置文件的Hi和OH吸收由两个组件，分离由125公里秒1。高斯拟合得到的色散为44公里秒1的两个组件的高吸收。OH吸收的曲线定性地类似于Hi吸收的曲线。OH吸收的两个分量都是热激发的。Hi吸收的两个分量的峰值光学深度分别为（7：3 0：4）10 2和（3：2 0：4）10 2。1667 MHz OH吸收的峰值光深分别为（2：30：3）10 2和（1：10：3）10 2。高速度分量的Hi和OH（1667 MHz）吸收线从（Oiii）5007，（Oi）6300和系统速度蓝移100 km s-1，但与（Oii）3727速度一致。我们解释这些速度的差异，由于冲击电离的一个区域，这是由于在前面的射电核冲击向前推，从而使明显的蓝移到喜，OH和（OII）的速度。Hi和OH吸收分量的光学深度比Hi = 1667，均为3，表明它们起源于致密的分子云。使用银河系分子云的OH/Av值，我们得到9< Av< 90朝向Mrk 1的视线。
We present Giant Meterwave Radio Telescope (GMRT) observations of the Hi 21 cm line and Very Large Array (VLA) observations of the OH 18 cm line from the Seyfert 2 galaxy Mrk 1. Hi emission is detected from both Mrk 1 and its companion NGC 451. The Hi emission morphology and the velocity field of Mrk 1 are disturbed. We speculate that the nuclear activities of Mrk 1 are triggered by tidal interactions. We estimate the Hi masses of Mrk 1 and NGC 451 to be 8:0(0:6) 10 8 M and 1:3(0:1) 10 9 M respectively. We have also detected the Hi 21 cm line and the OH 18 cm line in absorption toward the nucleus of Mrk 1 at a blueshifted velocity with respect to its systemic velocity indicating an outflow of atomic and molecular gas. Two OH lines, at 1665 and 1667 MHz, are detected. Each of the profiles of the Hi and OH absorption consists of two components that are separated by125 km s 1 . Gaussian fitting gave dispersions of44 km s 1 for both the components of the Hi absorption. The profile of the OH absorption is qualitatively similar to that of the Hi absorption. Both components of the OH absorption are thermally excited. The peak optical depths of the two components of the Hi absorption are (7:3 0:4) 10 2 and (3:2 0:4) 10 2 . The corresponding peak optical depths of the 1667 MHz OH absorption are (2:3 0:3) 10 2 and (1:1 0:3) 10 2 . The higher velocity components of the Hi and OH (1667 MHz) absorption lines are blueshifted from the (Oiii)5007, (Oi)6300, and the systemic velocity by100 km s 1 , but are consistent with the (Oii)3727 velocity. We explain these velocity discrepancies as due to shock ionization of a region which is pushed forward due to shocks in front of the radio nucleus thereby giving apparent blueshift to Hi, OH, and (Oii) velocities. The optical depth ratiosHi= 1667 of both the components of the Hi and OH absorption are3, indicating their origin in dense molecular clouds. Using OH/Av values for the Galactic molecular clouds, we obtain 9< Av< 90 toward the line of sight of Mrk 1.