V-LoTSS：圆偏振 LOFAR 两米天空巡天
星系天体物理
2023-02-22 v1 高能天体物理现象
太阳与恒星天体物理
摘要
我们呈报了迄今最灵敏的圆偏振射电巡天中 68 个射电源的探测结果。我们利用 144 MHz LOFAR 两米天空巡天的第二数据释放，制作了圆偏振地图，其噪声中值为 140 Jy beam，对约 27% 的北天（5634 deg）分辨率为 20。总强度向圆偏振的泄漏被测得约为 0.06%，且我们的巡天在流量密度 mJy 时是完备的。当圆偏振分数超过 1% 时，探测被视为可靠。我们发现圆偏振源群体由四类明显不同的对象组成：恒星系统、脉冲星、活动星系核，以及文献中未证认的源。恒星系统可进一步分为色球活动星、M 型矮星和褐矮星。基于圆偏振分数以及缺乏光学对应体，我们表明有可能推断那些未证认的源究竟是未知脉冲星还是褐矮星。到北天巡天完成时，我们预期将探测到 300100 个圆偏振源。
引用
@article{arxiv.2212.09815,
title = {V-LoTSS: The Circularly-Polarised LOFAR Two-metre Sky Survey},
author = {J. R. Callingham and T. W. Shimwell and H. K. Vedantham and C. G. Bassa and S. P. O'Sullivan and T. W. H. Yiu and S. Bloot and P. N. Best and M. J. Hardcastle and M. Haverkorn and R. D. Kavanagh and L. Lamy and B. J. S. Pope and H. J. A. Röttgering and D. J. Schwarz and C. Tasse and R. J. van Weeren and G. J. White and P. Zarka and D. J. Bomans and A. Bonafede and M. Bonato and A. Botteon and M. Bruggen and K. T. Chyży and A. Drabent and K. L. Emig and A. J. Gloudemans and G. Gürkan and M. Hajduk and D. N. Hoang and M. Hoeft and M. Iacobelli and M. Kadler and M. Kunert-Bajraszewska and B. Mingo and L. K. Morabito and D. G. Nair and M. Pérez-Torres and T. P. Ray and C. J. Riseley and A. Rowlinson and A. Shulevski and F. Sweijen and R. Timmerman and M. Vaccari and J. Zheng},
journal= {arXiv preprint arXiv:2212.09815},
year = {2023}
}
备注
Accepted for publication in A&A, 15 pages, 8 figures, 1 table. The catalogue will be publicly available at http://lofar-surveys.org/ and via Vizier shortly