标题： 《低频阵列射电望远镜两米波段天空巡天：深场数据释放2.》 一、 ELAIS-N1天区 显示英文标题

标题： The LOFAR Two-metre Sky Survey: Deep Fields Data Release 2. I. The ELAIS-N1 field

摘要： 我们展示了来自低频阵列（LOFAR）Two-metre Sky Survey 深度场项目（LoTSS 深度场）的 ELAIS-N1 区域的最终6''分辨率数据发布。144 MHz图像达到了迄今为止该频率下最灵敏的图像，并由7.5年内505小时源区观测获得的290 TB数据生成。这些数据按照之前LoTSS和LoTSS深度场数据发布的处理策略进行了处理。生成的图像覆盖了24.53平方度的面积，在此区域内通过改进的源检测方法识别出了由182,184个高斯分量组成的154,952个射电源。在6''分辨率下，地图的噪声水平达到10.7$\mu$Jy/波束，其中大约一半的噪声是由于源混淆引起的。在图像的大约7.4%区域中，我们受限于明亮源周围的动态范围，导致噪声进一步增加了超过5%。图像的流量密度标度精度约为9%，对于高显著性检测，我们的源位置与Pan-STARRS源位置之间的偏移标准差在赤经和赤纬方向上均为0.2''。我们搜索了单次观测图像中的变化源，确认了39个具有显著变化的对象。我们还搜索了圆极化源，发现了三个已知发射器（两颗恒星和一个脉冲星）的探测结果，同时限制了典型的偏振分数加泄漏小于0.045%。 显示英文摘要

摘要： We present the final 6'' resolution data release of the ELAIS-N1 field from the LOw-Frequency ARray (LOFAR) Two-metre Sky Survey Deep Fields project (LoTSS Deep). The 144MHz images are the most sensitive achieved to date at this frequency and were created from 290 TB of data obtained from 505 hrs on-source observations taken over 7.5 years. The data were processed following the strategies developed for previous LoTSS and LoTSS Deep data releases. The resulting images span 24.53 square degrees and, using a refined source detection approach, we identified 154,952 radio sources formed from 182,184 Gaussian components within this area. The maps reach a noise level of 10.7 $\mu$Jy/beam at 6'' resolution where approximately half of the noise is due to source confusion. In about 7.4% of the image our limited dynamic range around bright sources results in a further > 5% increase in the noise. The images have a flux density scale accuracy of about 9% and the standard deviation of offsets between our source positions and those from Pan-STARRS is 0.2'' in RA and Dec for high significance detections. We searched individual epoch images for variable sources, identifying 39 objects with considerable variation. We also searched for circularly polarised sources achieving three detections of previously known emitters (two stars and one pulsar) whilst constraining the typical polarisation fraction plus leakage to be less than 0.045%.