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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').

453 results found.

  1. Swift GRB 210818A: Global MASTER-Net observations report
  2. Fermi trigger No 649627691: Global MASTER-Net observations report
  3. GRB 210731A: Swift-XRT refined Analysis
  4. GRB 210731A: Swift/UVOT Detection of an optical afterglow
  5. Trigger 1062273: Swift detection of 4U 1700-377
  6. Fermi trigger No 649390368: Global MASTER-Net observations report
  7. GRB 210727A: AGILE/MCAL detection
  8. GRB 210722A: Fermi GBM observation
  9. GRB 210722A: Swift/UVOT Detection
  10. Fermi trigger No 647653174: Global MASTER-Net observations report
  11. Fermi trigger No 647641569: Global MASTER-Net observations report
  12. Swift GRB210708.10: Global MASTER-Net observations report
  13. Integral GRB210707.02: Global MASTER-Net observations report
  14. Swift-BAT Trigger 1055000/GRB210612.54: MASTER optical source observation
  15. Swift-BAT Trigger 1055000: Swift detection of an outburst from 4U 1543-47
  16. GRB 210606A: Fermi GBM detection
  17. Swift J1555.2-5402: Swift XRT refined analysis of the new SGR
  18. GRB 210520A: Swift-XRT observations
  19. GRB 210521A: MAXI/GSC detection
  20. Swift trigger 1047857 is 4U 1700-377
  21. Konus-Wind detection of GRB 210424B
  22. IceCube Alert 210416.09: Global MASTER-Net observations report
  23. GECAM detection of a burst possibly from the X-ray burster 4U 0614+09 or GRB 210124A
  24. GRB 210116A: AstroSat CZTI detection
  25. GRB 210119A: Insight-HXMT/HE detection
  26. Konus-Wind observation of GRB 201218A
  27. Swift GRB201209.24: Global MASTER-Net observations report
  28. Fermi trigger No 626247072: Global MASTER-Net observations report
  29. Baksan Neutrino Observatory Alert 201027.41: Global MASTER-Net observations report
  30. GRB 201021C: Swift-XRT refined Analysis
  31. Swift GRB201021.85: Global MASTER-Net observations report
  32. Fermi GRB 200929A: Global MASTER-Net observations report
  33. GRB 200919A: Swift-BAT refined analysis
  34. GRB 200914A: Fermi GBM observation
  35. Fermi GRB 200904A: Global MASTER-Net observations report
  36. AGILE detection of a burst (AGILE trigger no. 526185273)
  37. GRB 200829A: AGILE/MCAL detection
  38. Fermi-GBM Sub-Threshold candidate for GRB 200729A
  39. LIGO/Virgo MS200614bz: Test Identification of a binary neutron star candidate
  40. Fermi GRB 200607B: Global MASTER-Net observations report
  41. GRB 200528A: Swift-BAT refined analysis
  42. Swift GRB 200522A: Global MASTER-Net observations report
  43. IceCube Alert 200523.10: Global MASTER-Net observations report
  44. GRB 200519A: AstroSat CZTI detection
  45. Swift Detection of a burst from SGR Swift J1818.0-1607
  46. GRB200412B: GROWTH India detection of afterglow
  47. Fermi GRB 200412B: Global MASTER-Net observations report
  48. Fermi GBM Sub-Threshold Detection of GRB 200409A
  49. Fermi GRB 200403A: Global MASTER-Net observations report
  50. Fermi GRB 200402C: Global MASTER-Net observations report
  51. Fermi trigger No 607035413: Global MASTER-Net observations report
  52. Fermi trigger No 606614927: Global MASTER-Net observations report
  53. Swift GRB200303.11: Global MASTER-Net observations report
  54. Konus-Wind observation of GRB 200219C
  55. LIGO/Virgo S200225q: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  56. LIGO/Virgo S200219ac: no counterpart candidate in SVOM/GWAC-F30 observations
  57. LIGO/Virgo S200219ac: No counterpart candidates in KAIT observations
  58. LIGO/Virgo S200213t: No counterpart candidates in KAIT observations
  59. LIGO/Virgo S191222n: AstroSat CZTI upper limits
  60. LIGO/Virgo S200114f: AstroSat CZTI upper limits
  61. IceCube Alert 200109.99: Global MASTER-Net observations report
  62. IceCube Alert 200109.99: Global MASTER-Net observations report
  63. Fermi trigger No 599761015: Global MASTER-Net observations report
  64. GRB 191221B: MASTER VWFC OT yearly detection
  65. Fermi trigger No 598648473: Global MASTER-Net observations report
  66. IceCube Alert 191215.47: Global MASTER-Net observations report
  67. IceCube-191122A: Global MASTER-Net observations report
  68. Swift GRB191105.01: Global MASTER-Net observations report
  69. GRB 191031C: Prompt enhanced Swift-XRT position
  70. GRB 191023A: MASTER optical observation
  71. Swift GRB191011.19: Global MASTER-Net observations report
  72. Fermi trigger No 592211224: Global MASTER-Net observations report
  73. LIGO/Virgo S190930s: No counterpart candidates in KAIT observations
  74. LIGO/Virgo S190923y: INTEGRAL IBIS coded-masked imaging observations of part of the localization area and further all-sky upper limits
  75. LIGO/Virgo S190923y: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  76. Fermi trigger No 588931056 Global MASTER-Net observations report
  77. LIGO/Virgo S190828j: No counterpart candidates in KAIT observations
  78. Fermi trigger No 588115134 Global MASTER-Net observations report
  79. IceCube-190730A: MASTER optical observation
  80. Konus-Wind observation of GRB 190727B
  81. LIGO/Virgo S190718y: No counterpart candidates in CNEOST
  82. Fermi trigger No 584710308 Global MASTER-Net observations report
  83. LIGO/Virgo S190707q: MASTER OT seach result
  84. LIGO/Virgo S190706ai: No counterpart candidates in KAIT observations
  85. LIGO/Virgo S190706ai: No counterpart candidates in HAWC observations
  86. Fermi trigger No 582004649 Global MASTER-Net observations report
  87. GRB 190530A: Xinglong 2.16m optical observation
  88. LIGO/Virgo S190521r: CNEOST follow-up observations
  89. LIGO/Virgo S190513bm: INTEGRAL prompt observation
  90. LIGO/Virgo S190503bf: AstroSat CZTI upper limits
  91. Fermi GRB190505.05 Global MASTER-Net observations report
  92. LIGO/Virgo S190503bf: Fermi-GBM Observations
  93. LIGO/Virgo S190426c: CNEOST Optical Observations
  94. LIGO/Virgo S190425z: CNEOST Optical Observations
  95. Konus-Wind observation of GRB 190415A
  96. LIGO/Virgo S190408an: TMTS Optical Observation
  97. Trigger 888312: Swift detection of 4U 1901+03
  98. Konus-Wind observation of extremely bright GRB 190129B
  99. Konus-Wind observation of GRB 190114C
  100. Konus-Wind observation of GRB 190110A

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