NICER observation list: Target ID 754401

Abstract

GRS 1915+105 is a black hole binary known for its unique variability, strong winds, jets, and BH spin. After 20+ years in outburst, NICER detected a huge change in this iconic source: the X-ray flux dropped by 100x! Spectra suggest a large obscuring shroud, but what is this obscuring gas? The 'obscured' state is highly variable, with flares that reveal strong winds and highly-ionized absorption. We propose to study its long-term evolution with 35 weekly exposures of 2.7 ks in Cycle 6. NICER is the only mission capable of frequently monitoring this important new state. We also request a 25 ks NuSTAR ToO to constrain scattering and wind photoionziation. These observations will also grow a NICER legacy archive of obscured variability in GRS 1915+105.
Obsid RA DEC l b Start End Exposure Number of
Modules		 Number of
Processing		 Status of
Processing		 Date of
Processing		 Public
date
7544010101 288.798 10.946 45.366 -0.219 60371.4012 60371.4725 938.5 50 3 VALIDATED 60388.6 60385
7544010102 288.798 10.946 45.366 -0.219 60372.4987 60372.6988 1921.0 50 3 VALIDATED 60388.8 60386
7544010201 288.798 10.946 45.366 -0.219 60378.6283 60378.9604 4351.6 50 3 VALIDATED 60391.3 60392
7544010301 288.798 10.945 45.365 -0.219 60384.7609 60384.9676 2626.0 50 4 VALIDATED 60396.8 60398
7544010302 288.798 10.945 45.365 -0.219 60385.0206 60385.0317 857.0 50 4 VALIDATED 60396.9 60399
7544010401 288.798 10.945 45.365 -0.219 60391.2826 60391.2972 241.0 50 5 VALIDATED 60402.9 60405
7544010402 288.799 10.946 45.366 -0.219 60392.3815 60392.5158 1781.0 53 4 VALIDATED 60404.2 60406
7544010601 288.798 10.946 45.366 -0.219 60406.3262 60406.9148 3513.2 50 5 VALIDATED 60418.8 60420
7544010701 288.798 10.946 45.366 -0.219 60411.1796 60411.4514 0.0 41 5 VALIDATED 60423.2 60425
7544010801 288.798 10.948 45.368 -0.218 60420.9036 60420.9808 1108.0 50 4 VALIDATED 60432.7 60434
7544010802 288.798 10.948 45.367 -0.218 60421.0324 60421.1097 609.0 50 3 VALIDATED 60432.8 60435
7544011001 288.802 10.941 45.363 -0.225 60438.0704 60438.3988 0.0 17 5 VALIDATED 60449.9 60452
7544011101 288.799 10.946 45.366 -0.219 60441.6140 60441.9451 2699.0 50 4 VALIDATED 60452.3 60455
7544011102 288.798 10.946 45.365 -0.219 60443.4824 60443.8787 1201.2 50 6 VALIDATED 60466.2 60457
7544011201 288.797 10.945 45.365 -0.219 60449.4248 60449.5597 3222.0 50 4 VALIDATED 60466.6 60463
7544011301 288.798 10.945 45.365 -0.219 60456.0632 60456.3331 864.0 50 3 VALIDATED 60473.2 60470
7544011401 288.798 10.946 45.365 -0.219 60462.7725 60462.9097 2026.2 50 2 VALIDATED 60475.5 60476
7544011402 0.000 0.000 96.337 -60.189 60463.0148 60463.0263 0.0 50 1 VALIDATED 60475.5 60477
7544011501 288.798 10.945 45.366 -0.220 60470.4368 60470.5868 3248.0 52 3 VALIDATED 60486.5 60484
7544011601 288.798 10.945 45.366 -0.220 60477.0398 60477.7562 2571.2 41 2 VALIDATED 60489.2 60491
7544011701 288.798 10.946 45.366 -0.219 60483.7317 60483.9366 3429.0 52 4 VALIDATED 60494.5 60497
7544011801 288.798 10.947 45.366 -0.218 60489.7472 60489.7562 409.5 52 3 VALIDATED 60500.9 60503
7544011802 288.797 10.947 45.366 -0.218 60490.0051 60490.2074 1654.2 52 4 VALIDATED 60500.9 60504
7544011901 288.797 10.947 45.367 -0.218 60497.8799 60497.9521 699.0 41 4 VALIDATED 60508.2 60511
7544011902 288.798 10.947 45.367 -0.218 60498.0090 60498.5347 3462.9 41 5 VALIDATED 60509.8 60512
7544012001 288.803 10.947 45.369 -0.222 60504.2596 60504.6588 6283.0 50 4 VALIDATED 60515.6 60518
7544012101 288.800 10.946 45.367 -0.220 60511.6801 60511.9433 551.0 41 6 VALIDATED 60531.1 60525
7544012102 288.801 10.946 45.367 -0.222 60512.0025 60512.5250 1654.0 41 6 VALIDATED 60531.2 60526
7544012201 288.798 10.946 45.365 -0.219 60518.0658 60518.2641 1263.0 41 5 VALIDATED 60542.4 60532
7544012202 288.798 10.946 45.366 -0.219 60519.0332 60519.7539 2202.0 41 5 VALIDATED 60542.6 60533
7544012301 288.797 10.943 45.363 -0.219 60525.0335 60525.6227 3755.0 41 4 VALIDATED 60540.2 60539
7544012401 288.802 10.946 45.368 -0.223 60534.6028 60534.6745 318.0 52 2 VALIDATED 60545.5 60548
7544012402 288.802 10.943 45.365 -0.224 60535.1762 60535.2474 948.0 52 2 VALIDATED 60545.6 60549
7544012501 288.800 10.946 45.367 -0.221 60540.7278 60540.9961 1989.0 52 3 VALIDATED 60552.0 60554
7544012502 288.802 10.947 45.368 -0.222 60541.2484 60541.2616 332.0 52 4 VALIDATED 60552.1 60555
7544012601 288.799 10.945 45.366 -0.220 60548.4731 60548.5530 3075.0 52 3 VALIDATED 60559.6 60562
7544012701 288.798 10.947 45.366 -0.219 60554.8755 60554.9444 633.0 50 3 VALIDATED 60565.3 60568
7544012702 288.798 10.947 45.367 -0.219 60555.0046 60555.5898 3030.0 50 4 VALIDATED 60565.3 60569
7544012801 288.798 10.948 45.367 -0.218 60562.0197 60562.6090 1952.0 41 4 VALIDATED 60574.1 60576
7544012901 288.799 10.946 45.366 -0.219 60570.4854 60570.6933 2028.0 50 5 VALIDATED 60591.4 60584
7544013001 288.800 10.945 45.366 -0.221 60577.1998 60577.7843 83.0 22 6 VALIDATED 60591.7 60591
7544013101 288.799 10.947 45.367 -0.219 60583.9139 60583.9944 0.0 50 5 VALIDATED 60595.3 60597
7544013201 288.794 10.940 45.359 -0.218 60590.1008 60590.4956 0.0 41 4 VALIDATED 60602.0 60604
7544013301 288.798 10.946 45.366 -0.219 60597.1325 60597.2850 0.0 41 3 VALIDATED 60607.2 60611
7544013601 288.798 10.945 45.366 -0.220 60620.1198 60620.9035 2691.0 50 4 VALIDATED 60632.0 60634
7544013602 288.799 10.945 45.366 -0.220 60621.0240 60621.2907 1415.0 50 3 VALIDATED 60632.1 60635
7544013701 288.800 10.945 45.366 -0.221 60623.0060 60623.0766 0.0 0 7 VALIDATED 60639.9 60637
7544013702 288.798 10.946 45.366 -0.219 60625.0229 60625.3539 3840.0 50 7 VALIDATED 60640.1 60639
7544013703 288.799 10.946 45.366 -0.220 60626.4211 60626.4947 0.0 11 6 VALIDATED 60638.4 60640
7544015101 288.798 10.945 45.365 -0.219 60734.2956 60734.9465 2729.0 50 4 VALIDATED 60746.6 60748