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As shown in Fig. 1, LoTSS-DR2 consists of 841 pointings and it covers a total of 5634 square degrees which corresponds approximately to our contiguous coverage at the time of beginning the LoTSS-DR2 processing run. The data release is formed by two contiguous regions that are centred at approximately 12h45m00s +44◦30′00′′(RA-13 region) and 1h00m00s +28◦00′00′′(RA-1 region) and span 4178 and 1457 square degrees, or 626 and 215 pointings, respectively. The data were  taken between 2014-05-23 to 2020-02-05 as part of the LoTSS  projects LC2_038, LC3_008, LC4_034, LT5_007, LC6_015, LC7_024, LC8_022, LC9_030, LT10_010 and the co-observing projects LC8_014, LC8_030, DDT9_001, LC9_011, LC9_012, LC9_019,LC9_020,COM10_001,LC10_001,LC10_010,  LC10_014,LT10_012,LC11_013,LC11_016,LC11_019, LC11_020, LC12_014. All the data that were processed as part of this data release are stored in the LOFAR Long Term Archive (LTA) with approximately 62% in Forschungszentrum Jülich, 32% in SURF8and the remaining 6% in Poznan. The vast majority of pointings were observed for a total of 8 hrs with 48 MHz (120-168 MHz) of bandwidth which allows for two pointings to be observed simultaneously with current LOFAR capabilities. However, primarily due to the co-observing program10through which we exploit the multi-beam capability of LOFAR and accumulate LoTSS data simultaneously with observations conducted for other projects, for 18 of the pointings in LoTSS-DR2 we have used data that has the same frequency coverage but a total integration time of∼16 hrs. The overall observing time utilised for this data release is 3451 hrs and the volume of archived data that  was processed is 7.6 PB. Thus the average data size for an 8 hr pointing (two observed simultaneously) is 8.8 TB but there is significant variation because data that have been recorded since 2018-09-11 are typically five times smaller than those before this date due to Dysco compression (Offringa 2016) being utilised by the radio observatory prior to ingesting data into the LTA in more recent observations.

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