SGR1935+2154
Contents
General Information
- Name of the source: SGR 1935+2154
- Brief description of the source:
- Object type : Soft Gamma Repeater, Galactic Magnetar
- Other relevant information: Its simultaneous X-ray bursts (INTEGRAL, AGILE) and Fast radio Bursts (CHIME) on April 28th, 2020 were associated, providing the first evidence that FRBs can originate from magnetars.
- RA: 19 35 00.0 (hh mm ss), Dec: +21 53 59.1 (dd mm ss)
- RA, Dec in deg (ICRS): 293.75, 21.90
- Galactic Coordinates l=57.26, b=0.81
SGR 1935+2154 is a Galactic magnetar that presents two types of high-energy emission:
- the persistent emission at few keV
- the transient emission of short nonthermal bursts at keV−MeV. The transient emission is characterized by occasional activity period lasting days-weeks with tens-hundreds of random, short (≈0.1s) and irregular bursts.
People involved
- Gabriele Panebianco (gabriele.panebianco@inaf.it)
- Rubén López-Coto (rlopezcoto@iaa.es)
- Andrea Bulgarelli
- Pol Bordas
- Paolo Da Vela
- Tarek Hassan
- Alicia López-Oramas
- Ambra Di Piano
- Nicolò Parmiggiani
- Irene Jimenez Martinez
Presentations
- 2023-06-05 LST Analysis Call (reco meeting): link to pdf
- 2023-06-19 LST General Meeting: link to pdf
- 2023-07-21 LST Galactic Group Meeting: link to pdf
- 2023-11-08 LST General Meeting: link to pdf
- 2024-01-15 Contributed talk at VHEGAM Conference: link to SAPO XWiki
- 2024-02-19 LST Analysis Call (reco meeting): link to pdf
- 2024-03-22 LST Galactic Group Meeting: link to pdf
- 2024-04-15 Contributed poster at CTA Symposium: link to XWiki
Data-taking Information
SGR 1935+2154 was observed during July 2021, September 2021, June 2022, October 2022 as follow up to external science alerts. SGR 1935+2154 was observed for a total of 37.7 hours over 118 runs in 17 nights.
Roughly half of the observations were conducted with MAGIC.
Observations are quasi-simultaneous to other facilities observations, both at VHE and MWL.
Observations are simultaneous to 9 time of alerts of high-energy satellites triggered by SGR 1935+2154 bursts.
Most observations are in Wobble mode, though some runs were taken in ON mode but without OFF observations (this is the case for all October 2022 runs and 4 July 2021 runs).
Run Number | Night | Run Start Time [UTC] | Run Elapsed Time [s] | Source Offset [deg] | Mean pointing azimuth [deg] | Mean pointing zenith [deg] | Used in stacked analysis | mode |
---|---|---|---|---|---|---|---|---|
5154 | 20210706 | 2021-07-06 21:35:40.008366 | 967.415 | 0.348 | 81.331 | 56.930 | False | wobble |
5155 | 20210706 | 2021-07-06 21:55:39.538852 | 1016.190 | 0.451 | 83.681 | 51.829 | False | wobble |
5156 | 20210706 | 2021-07-06 22:18:14.314086 | 1053.514 | 0.372 | 85.327 | 47.133 | True | wobble |
5157 | 20210706 | 2021-07-06 22:41:17.329760 | 1205.443 | 0.434 | 88.929 | 42.344 | True | wobble |
5158 | 20210706 | 2021-07-06 23:03:40.273986 | 1205.356 | 0.357 | 90.827 | 37.672 | True | wobble |
5161 | 20210706 | 2021-07-06 23:38:21.458475 | 1206.221 | 0.443 | 96.226 | 29.316 | True | wobble |
5162 | 20210706 | 2021-07-07 00:00:21.764677 | 1205.398 | 0.442 | 100.261 | 24.532 | True | wobble |
5163 | 20210706 | 2021-07-07 00:25:00.965802 | 1443.322 | 0.368 | 104.802 | 19.462 | True | wobble |
5164 | 20210706 | 2021-07-07 00:49:25.963768 | 1145.974 | 0.436 | 116.293 | 14.803 | True | wobble |
5165 | 20210706 | 2021-07-07 01:10:44.258733 | 1203.290 | 0.365 | 127.337 | 10.904 | True | wobble |
5166 | 20210706 | 2021-07-07 01:32:50.001943 | 1203.480 | 0.437 | 158.649 | 7.453 | True | wobble |
5167 | 20210706 | 2021-07-07 01:54:27.456639 | 1206.198 | 0.367 | 195.814 | 6.820 | True | wobble |
5168 | 20210706 | 2021-07-07 02:16:10.395605 | 1205.429 | 0.436 | 224.205 | 9.957 | True | wobble |
5169 | 20210706 | 2021-07-07 02:38:19.418482 | 1205.540 | 0.370 | 241.561 | 13.290 | True | wobble |
5170 | 20210706 | 2021-07-07 02:59:59.232267 | 1205.947 | 0.432 | 252.307 | 18.372 | True | wobble |
5171 | 20210706 | 2021-07-07 03:22:42.369718 | 1203.333 | 0.367 | 258.984 | 22.682 | True | wobble |
5175 | 20210706 | 2021-07-07 04:15:42.475526 | 1205.977 | 0.434 | 266.547 | 34.509 | True | wobble |
5176 | 20210706 | 2021-07-07 04:35:08.352232 | 905.936 | 0.377 | 269.512 | 38.264 | True | wobble |
5192 | 20210707 | 2021-07-08 01:19:53.546984 | 1204.101 | 0.022 | 142.520 | 8.584 | False | ON |
5193 | 20210707 | 2021-07-08 01:41:14.972905 | 1205.786 | 0.021 | 177.694 | 6.946 | False | ON |
5194 | 20210707 | 2021-07-08 02:02:34.873506 | 1204.280 | 0.020 | 214.208 | 8.269 | False | ON |
5195 | 20210707 | 2021-07-08 02:16:24.810369 | 292.236 | 0.019 | 230.309 | 10.271 | False | ON |
5196 | 20210707 | 2021-07-08 02:25:59.058815 | 605.461 | 0.381 | 236.500 | 11.662 | True | wobble |
5197 | 20210707 | 2021-07-08 02:38:06.497275 | 606.417 | 0.418 | 245.497 | 14.658 | True | wobble |
5198 | 20210707 | 2021-07-08 02:51:02.354297 | 602.274 | 0.398 | 251.387 | 16.760 | True | wobble |
5199 | 20210707 | 2021-07-08 03:03:00.516614 | 605.874 | 0.402 | 252.977 | 19.611 | True | wobble |
5211 | 20210709 | 2021-07-09 22:50:58.651400 | 1205.470 | 0.370 | 90.657 | 37.872 | True | wobble |
5212 | 20210709 | 2021-07-09 23:15:16.868188 | 1205.343 | 0.428 | 94.403 | 31.785 | True | wobble |
5213 | 20210709 | 2021-07-09 23:46:33.454934 | 1205.261 | 0.399 | 98.543 | 25.197 | True | wobble |
5214 | 20210709 | 2021-07-10 00:10:33.631798 | 1201.304 | 0.402 | 106.053 | 20.354 | True | wobble |
5215 | 20210709 | 2021-07-10 00:34:57.851661 | 1204.504 | 0.376 | 112.827 | 15.470 | True | wobble |
5216 | 20210709 | 2021-07-10 01:00:10.746264 | 1206.832 | 0.422 | 131.291 | 10.101 | True | wobble |
5217 | 20210709 | 2021-07-10 01:24:30.383948 | 1205.869 | 0.398 | 160.492 | 6.922 | True | wobble |
5218 | 20210709 | 2021-07-10 01:49:41.124249 | 1206.164 | 0.403 | 205.604 | 8.073 | True | wobble |
5253 | 20210712 | 2021-07-13 00:58:23.075673 | 1205.001 | 0.379 | 138.150 | 9.080 | True | wobble |
5254 | 20210712 | 2021-07-13 01:23:14.131849 | 1206.654 | 0.420 | 184.029 | 6.975 | True | wobble |
5255 | 20210712 | 2021-07-13 01:47:16.445606 | 1203.150 | 0.398 | 221.435 | 8.531 | True | wobble |
5256 | 20210712 | 2021-07-13 02:11:20.228025 | 1201.871 | 0.403 | 239.169 | 13.172 | True | wobble |
5257 | 20210712 | 2021-07-13 02:33:55.047752 | 1205.168 | 0.383 | 250.357 | 17.114 | True | wobble |
5258 | 20210712 | 2021-07-13 02:58:36.310374 | 1206.582 | 0.415 | 258.359 | 23.067 | True | wobble |
5281 | 20210716 | 2021-07-17 01:58:45.359084 | 606.296 | 0.382 | 241.680 | 13.200 | True | wobble |
5284 | 20210716 | 2021-07-17 02:56:34.882860 | 1205.573 | 0.414 | 261.193 | 26.029 | True | wobble |
5285 | 20210716 | 2021-07-17 03:20:04.027781 | 1205.415 | 0.399 | 265.644 | 30.642 | True | wobble |
5286 | 20210716 | 2021-07-17 03:37:31.978401 | 486.510 | 0.401 | 266.766 | 34.734 | True | wobble |
5294 | 20210717 | 2021-07-18 00:00:54.795768 | 1205.661 | 0.376 | 111.738 | 15.997 | False | wobble |
5295 | 20210717 | 2021-07-18 00:24:54.352744 | 1205.205 | 0.422 | 127.894 | 10.745 | False | wobble |
5299 | 20210717 | 2021-07-18 01:13:54.687818 | 1206.271 | 0.398 | 200.712 | 6.971 | True | wobble |
5300 | 20210717 | 2021-07-18 01:37:59.408685 | 1206.359 | 0.403 | 229.105 | 10.732 | True | wobble |
5301 | 20210717 | 2021-07-18 02:03:47.384962 | 1205.794 | 0.383 | 246.089 | 14.978 | True | wobble |
5320 | 20210718 | 2021-07-19 00:20:59.428245 | 1206.284 | 0.378 | 125.137 | 11.347 | False | wobble |
5321 | 20210718 | 2021-07-19 00:45:18.481347 | 1206.659 | 0.421 | 157.894 | 7.455 | False | wobble |
5322 | 20210718 | 2021-07-19 01:10:06.164715 | 1203.304 | 0.398 | 200.913 | 6.987 | False | wobble |
5326 | 20210718 | 2021-07-19 01:53:36.855329 | 1206.637 | 0.402 | 242.509 | 14.294 | True | wobble |
5327 | 20210718 | 2021-07-19 02:18:57.552751 | 1202.194 | 0.384 | 253.242 | 18.914 | True | wobble |
5328 | 20210718 | 2021-07-19 02:43:21.359871 | 1201.198 | 0.414 | 260.142 | 24.866 | True | wobble |
5329 | 20210718 | 2021-07-19 03:07:08.815895 | 1206.109 | 0.399 | 264.874 | 29.535 | True | wobble |
5330 | 20210718 | 2021-07-19 03:30:44.162188 | 1206.552 | 0.401 | 266.901 | 34.969 | True | wobble |
6125 | 20210907 | 2021-09-07 20:59:10.755258 | 1205.524 | 0.378 | 124.154 | 11.577 | True | wobble |
6126 | 20210907 | 2021-09-07 21:23:12.990901 | 1205.299 | 0.421 | 155.315 | 7.588 | True | wobble |
6127 | 20210907 | 2021-09-07 21:47:15.248035 | 1205.164 | 0.398 | 196.709 | 6.816 | True | wobble |
6128 | 20210907 | 2021-09-07 22:10:35.035322 | 1205.448 | 0.403 | 226.375 | 10.253 | True | wobble |
6129 | 20210907 | 2021-09-07 22:33:47.974373 | 1205.418 | 0.383 | 243.388 | 13.879 | True | wobble |
6198 | 20210910 | 2021-09-10 21:00:37.748895 | 1157.028 | 0.421 | 139.966 | 8.843 | True | wobble |
6199 | 20210910 | 2021-09-10 21:22:28.734336 | 1159.121 | 0.398 | 171.222 | 6.611 | True | wobble |
6200 | 20210910 | 2021-09-10 21:43:20.062237 | 1172.043 | 0.403 | 207.669 | 8.199 | True | wobble |
6201 | 20210910 | 2021-09-10 22:06:16.572737 | 1400.066 | 0.382 | 232.938 | 10.951 | True | wobble |
6202 | 20210910 | 2021-09-10 22:38:58.567869 | 1208.935 | 0.416 | 251.895 | 18.029 | True | wobble |
6203 | 20210910 | 2021-09-10 23:00:16.579873 | 1166.859 | 0.398 | 258.398 | 22.026 | True | wobble |
6204 | 20210910 | 2021-09-10 23:21:18.495585 | 1202.413 | 0.402 | 260.967 | 26.864 | True | wobble |
6205 | 20210910 | 2021-09-10 23:42:55.358996 | 1211.386 | 0.387 | 265.112 | 31.062 | True | wobble |
6206 | 20210910 | 2021-09-11 00:02:55.673674 | 1217.310 | 0.411 | 268.387 | 36.205 | False | wobble |
6208 | 20210910 | 2021-09-11 00:47:32.362278 | 1206.405 | 0.399 | 272.881 | 45.754 | True | wobble |
6223 | 20210911 | 2021-09-11 22:47:39.440023 | 1188.808 | 0.384 | 254.708 | 19.958 | True | wobble |
6224 | 20210911 | 2021-09-11 23:09:07.997514 | 1188.388 | 0.414 | 260.555 | 25.306 | True | wobble |
6225 | 20210911 | 2021-09-11 23:30:04.701359 | 1148.914 | 0.399 | 264.754 | 29.356 | True | wobble |
6226 | 20210911 | 2021-09-11 23:49:53.932634 | 1204.881 | 0.401 | 266.265 | 33.963 | True | wobble |
6227 | 20210911 | 2021-09-12 00:12:02.313915 | 1172.191 | 0.390 | 269.596 | 38.313 | False | wobble |
6228 | 20210911 | 2021-09-12 00:30:34.922076 | 866.843 | 0.408 | 272.167 | 43.141 | False | wobble |
6229 | 20210911 | 2021-09-12 00:47:58.089294 | 906.975 | 0.401 | 274.398 | 46.445 | True | wobble |
6244 | 20210912 | 2021-09-12 21:53:20.006110 | 1284.220 | 0.382 | 228.547 | 10.084 | False | wobble |
6245 | 20210912 | 2021-09-12 22:15:07.177227 | 1181.297 | 0.417 | 245.585 | 14.756 | False | wobble |
6246 | 20210912 | 2021-09-12 22:36:24.544463 | 1197.066 | 0.398 | 254.190 | 18.612 | False | wobble |
6247 | 20210912 | 2021-09-12 22:58:01.640121 | 1232.768 | 0.402 | 257.764 | 23.537 | False | wobble |
6248 | 20210912 | 2021-09-12 23:19:36.515968 | 1208.833 | 0.386 | 262.595 | 27.689 | False | wobble |
6249 | 20210912 | 2021-09-12 23:50:33.302675 | 1328.482 | 0.411 | 267.791 | 35.214 | True | wobble |
6250 | 20210912 | 2021-09-13 00:05:53.763888 | 328.248 | 0.400 | 270.158 | 38.076 | True | wobble |
6251 | 20210912 | 2021-09-13 00:19:51.266180 | 1236.984 | 0.400 | 270.625 | 41.402 | True | wobble |
6252 | 20210912 | 2021-09-13 00:41:51.959164 | 1153.771 | 0.393 | 273.459 | 45.724 | True | wobble |
6253 | 20210912 | 2021-09-13 00:57:51.387474 | 595.861 | 0.405 | 275.503 | 49.979 | True | wobble |
6269 | 20210913 | 2021-09-13 22:58:57.497780 | 1562.563 | 0.385 | 259.350 | 24.064 | False | wobble |
6271 | 20210913 | 2021-09-13 23:30:41.016183 | 312.418 | 0.387 | 265.064 | 30.965 | False | wobble |
6272 | 20210913 | 2021-09-13 23:49:12.585701 | 28.083 | 0.388 | 267.697 | 35.026 | False | wobble |
6273 | 20210913 | 2021-09-14 00:00:57.099488 | 1229.859 | 0.410 | 269.620 | 38.362 | False | wobble |
6288 | 20210914 | 2021-09-15 00:04:45.977484 | 1164.339 | 0.400 | 269.760 | 39.817 | False | wobble |
6289 | 20210914 | 2021-09-15 00:25:30.855964 | 1163.854 | 0.392 | 272.532 | 43.863 | False | wobble |
6290 | 20210914 | 2021-09-15 00:46:18.103774 | 1208.983 | 0.406 | 275.120 | 49.172 | False | wobble |
6291 | 20210914 | 2021-09-15 01:08:00.772730 | 1193.965 | 0.402 | 277.627 | 53.399 | False | wobble |
8607 | 20220602 | 2022-06-03 02:18:17.116211 | 1168.144 | 0.375 | 100.131 | 24.574 | True | wobble |
8608 | 20220602 | 2022-06-03 02:39:12.544475 | 1189.029 | 0.423 | 106.122 | 19.362 | True | wobble |
8610 | 20220602 | 2022-06-03 03:12:23.674925 | 1175.487 | 0.399 | 117.749 | 12.744 | True | wobble |
8611 | 20220602 | 2022-06-03 03:32:43.771255 | 1134.869 | 0.402 | 137.193 | 9.706 | True | wobble |
8612 | 20220602 | 2022-06-03 03:52:58.185166 | 1134.483 | 0.380 | 161.859 | 7.264 | True | wobble |
8613 | 20220602 | 2022-06-03 04:12:50.695077 | 1130.355 | 0.418 | 204.330 | 7.555 | True | wobble |
8614 | 20220602 | 2022-06-03 04:28:44.929503 | 630.429 | 0.398 | 225.667 | 8.973 | True | wobble |
8891 | 20220624 | 2022-06-25 01:38:48.786781 | 1239.415 | 0.402 | 116.787 | 14.563 | True | wobble |
8892 | 20220624 | 2022-06-25 02:04:18.557745 | 1173.345 | 0.379 | 131.935 | 9.980 | True | wobble |
8893 | 20220624 | 2022-06-25 02:24:22.669043 | 1151.907 | 0.419 | 164.241 | 7.185 | True | wobble |
8894 | 20220624 | 2022-06-25 02:44:34.480588 | 1152.283 | 0.398 | 199.396 | 6.903 | True | wobble |
8895 | 20220624 | 2022-06-25 03:04:38.363385 | 1154.168 | 0.402 | 224.591 | 9.965 | True | wobble |
8896 | 20220624 | 2022-06-25 03:22:02.053649 | 841.338 | 0.383 | 239.084 | 12.399 | True | wobble |
9722 | 20221019 | 2022-10-19 20:30:27.600677 | 1794.876 | 0.015 | 257.908 | 22.698 | False | ON |
9723 | 20221019 | 2022-10-19 21:00:12.800844 | 1206.477 | 0.012 | 263.753 | 29.174 | False | ON |
9724 | 20221019 | 2022-10-19 21:21:36.919730 | 1205.612 | 0.011 | 266.964 | 33.859 | False | ON |
9725 | 20221019 | 2022-10-19 21:43:03.569971 | 1206.730 | 0.009 | 269.741 | 38.567 | False | ON |
9726 | 20221019 | 2022-10-19 22:04:13.933069 | 1206.449 | 0.008 | 272.208 | 43.217 | False | ON |
9727 | 20221019 | 2022-10-19 22:26:16.460377 | 1205.381 | 0.006 | 274.589 | 48.049 | False | ON |
9728 | 20221019 | 2022-10-19 22:43:13.303530 | 605.614 | 0.004 | 276.339 | 51.755 | False | ON |
9752 | 20221020 | 2022-10-20 21:02:33.395669 | 5316.643 | 0.012 | 264.317 | 30.563 | False | ON |
Data analysis Information
SGR 1935+2154 is a Galactic magnetar that presents two types of high-energy emission: the persistent emission and the transient emission, hence we performed two types of analysis.
Common starting point are the DL1b produced by lstosa.
To reconstruct the events properties and obtain DL2 data, we employed a set of Random Forests trained with Monte Carlo (MC) simulations tuned to the Night Sky background (NSB) level of our data.
- Monte Carlo simulations of DL2 and trained RF were requested to lstmcpipe team, NSB tuned. MC prod name: 20230428_src_dec2276_tuned_nsb_az_tel
- lstchain version: 0.9.13
TODO: report NSB parameters here.
- The persistent emission analysis is a "standard" stacked spectral analysis.
- We obtained DL3 and IRFs with a set of "standard" cuts (details below).
- We selected "good quality" runs (25h of data).
- Results are upper limits on the SED and Light Curve on 3 time scales: all stacked data (25h), night-wise (approx 2h), run-wise (approx 20m)
- The transient analysis is energy-integrated due to poor statistics, and focuses on 100ms time scale.
- The cuts were chosen to optimise the short-scale sensitivity (details below). This method can be used for the detection of other short transients too.
- We obtained a new set of DL3 and IRFs with the short scale cuts. We placed upper limits to SGR flux on the 9 time intervals (100ms) centered around the 9 simultaneous Time of Alerts, plus the stacked upper limit
- We searched for non-simultaneous bursts in all our data, without any detection.
Analysis of Persistent Emission
Bad quality runs and runs taken in ON mode were discarded from the analysis. The SGR 1935+2154 analysis covers 25.8 hours of observations over 83 runs and 13 nights. Plots can be found in presentation pdf.
- Runs exclusion criteria (info taken from long-term data check files):
- Source offset not in [0.35,0.45] deg.
- Rate of cosmics < 2500 evt/s
- Pedestal charge standard deviation > 2 P.E.
- IRFs were computed point-like and with energy-dependent cuts.
- GH-efficiency: 0.7.
- Theta Containment: 0.68
- Event selector filter: INTENSITY>80 P.E.
- High-level analysis was performed with gammapy v1.0
- Standard Wobble Analysis was performed with 1 off region.
- Flux Points upper limits were obtained for the source under different conditions:
- SED ULs in [0.1, 10] TeV, 5 bins per energy decade.
- 1 set of stacked ULs for total integrated livetime.
- 13 sets of night-wise ULs.
- Light Curve UL run-wise and night-wise, energy integrated in [0.1, 50] TeV
- SED ULs in [0.1, 10] TeV, 5 bins per energy decade.
Cuts optimization for a short-scale emission
See slides.
Analysis of Transient Emission
See slides.
Results recap
WIP.