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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').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

3820 results found.

  1. Fermi trigger No 746923430: Global MASTER-Net observations report
  2. GRB 240828A: SAO RAS AS-500(2) optical observations
  3. GRB 240829B: GRBAlpha detection
  4. GRB 240828B: AbAO optical upper limit
  5. GRB 240828B: GRANDMA Optical Upper Limit
  6. GRB 240825A: MeerKAT detection
  7. GRB 240828B: SAO RAS optical upper limit
  8. GRB 240828A: SAO RAS optical observations
  9. Fermi trigger No 746587425: Global MASTER-Net observations report
  10. GRB 240829B: Fermi GBM Final Localization
  11. GRB 240629A: First GRB Detected by BurstCube
  12. GRB 240828A: KAIT Optical Afterglow Candidate
  13. Swift GRB240829.16: Global MASTER-Net observations report
  14. LAT GRB240828.62: Global MASTER-Net observations report
  15. Fermi trigger No 746438824: Global MASTER-Net observations report
  16. GRB 240825A: SAO RAS optical observations
  17. GRB 240824A: GIT optical upper limit
  18. SGR 1E 1841-045 / Kes 73: SVOM/GRM observation
  19. SGR 1E 1841-045 / Kes 73 (Trigger 1249878): Osservatorio Atronomico Nastro Verde optical upper limit
  20. Fermi GRB 240825A: Global MASTER-Net observations report
  21. SGR 1E 1841-045 / Kes 73 (Trigger 1249653) - Osservatorio Astronomico Nastro Verde upper limit
  22. SGR 1E 1841-045 / Kes 73: Leavitt Observatory optical upper limit
  23. SGR 1E 1841-045 / Kes 73: Montarrenti Observatory optical upper limits
  24. GECAM-B observation of a short burst from SGR 1E 1841-045 / Kes 73
  25. Fermi-GBM Observations of the reactivation of SGR 1E 1841-045 / Kes 73
  26. Fermi trigger No 745866488: Global MASTER-Net observations report
  27. Trigger 1249878: Swift detection of another burst from SGR 1E 1841-045 / Kes 73
  28. Trigger 1249653: Swift detection of SGR 1E 1841-045 / Kes 73
  29. GRB 240819A: X-ray follow-up observation with EP-FXT
  30. EP240816b: Liverpool Telescope optical follow-up observations
  31. EP EP240816b: Global MASTER-Net observations report
  32. Fermi GRB 240814C: Global MASTER-Net observations report
  33. Fermi trigger No 745306088: Global MASTER-Net observations report
  34. Fermi GRB 240814B: Global MASTER-Net observations report
  35. Fermi GRB 240810A: Global MASTER-Net observations report
  36. GRB 240809A: Swift detection of a burst with a bright optical counterpart
  37. EP EP240807a: Global MASTER-Net observations report
  38. EP EP240806a: Global MASTER-Net observations report
  39. Fermi trigger No 744761058: Global MASTER-Net observations report
  40. EP240807a/GRB 240807A: EP-FXT detection of the X-ray emission
  41. EP240806A: Liverpool Telescope optical follow-up observations
  42. Fermi trigger No 744629911: Global MASTER-Net observations report
  43. Konus-Wind detection of GRB 240802A (EP240802a)
  44. GRB 240805B: NUTTelA-TAO / BSTI Optical Limits
  45. Fermi trigger No 744544656: Global MASTER-Net observations report
  46. GRB 240802A: AstroSat CZTI detection of a long burst
  47. Fermi trigger No 744128417: Global MASTER-Net observations report
  48. Fermi trigger No 743953682: Global MASTER-Net observations report
  49. Fermi Gamma-ray Burst Monitor trigger 743953682/240729575 is not a GRB
  50. Fermi GRB 240727A: Global MASTER-Net observations report
  51. GRB 240718A: GRBAlpha detection
  52. GRB 240627A: GRBAlpha detection
  53. Fermi GRB 240726A: Global MASTER-Net observations report
  54. Fermi trigger No 743345551: Global MASTER-Net observations report
  55. Fermi trigger No 743219692: Global MASTER-Net observations report
  56. Swift GRB240720.02: Global MASTER-Net observations report
  57. Konus-Wind detection of GRB 240718A
  58. Fermi GRB 240718A: Global MASTER-Net observations report
  59. GRB 240718A: Fermi GBM Observation
  60. IceCube-Cascade 240714A: TRT optical observations on the EP/FXT positions
  61. GRB 240718A: Fermi-LAT Detection
  62. GRB 240718A: SVOM/GRM observation
  63. GRB 240718A: BALROG localization (Fermi Trigger 742976945 / GRB 240718270)
  64. GRB 240718A: Fermi GBM Final Real-time Localization
  65. IPN triangulation of GRB 240715A (short)
  66. JinShan confirmation of the EP-WXT source triggered on July 14th due to a flaring star
  67. GRB 240712A: Swift detection of a burst
  68. Fermi trigger No 742317942: Global MASTER-Net observations report
  69. LIGO/Virgo S240615dg: Swift XRT observations, 28 futher X-ray sources
  70. LIGO/Virgo/KAGRA S240629by: Coverage and upper limits from MAXI/GSC observations
  71. Fermi trigger No 741356809: Global MASTER-Net observations report
  72. Fermi GRB 240629A: Global MASTER-Net observations report
  73. Fermi Gamma-ray Burst Monitor trigger 741362867/240629589 is not a GRB
  74. GRB 240629A: BALROG localization (Fermi Trigger 741372837 / GRB 240629704)
  75. GRB 240629A: Fermi GBM Final Real-time Localization
  76. Fermi Gamma-ray Burst Monitor trigger 741356809/240629519 is not a GRB
  77. LIGO/Virgo/KAGRA S240629by: Identification of a GW compact binary merger candidate
  78. Konus-Wind detection of GRB 240619A
  79. Fermi trigger No 740949590: Global MASTER-Net observations report
  80. GRB 240529A: JinShan optical observations
  81. Fermi trigger No 740474239: Global MASTER-Net observations report
  82. LIGO/Virgo S240615dg: Swift XRT observations, 39 X-ray sources
  83. Fermi trigger No 740430582: Global MASTER-Net observations report
  84. Fermi GRB 240616A: Global MASTER-Net observations report
  85. Fermi trigger No 740166710: Global MASTER-Net observations report
  86. GRB 240612A: GRBAlpha detection
  87. Fermi GRB 240611A: Global MASTER-Net observations report
  88. GRB 240529A : MITSuME Akeno optical afterglow detection
  89. Fermi GRB 240604A: Global MASTER-Net observations report
  90. Fermi GRB 240605A: Global MASTER-Net observations report
  91. GRB 240529A: MASTER prompt OT detection
  92. Fermi GRB 240602A: Global MASTER-Net observations report
  93. The EP-WXT source triggered on June 1st is likely a flaring star
  94. GRB 240529A: AKO Optical Afterglow Follow-Up Observations
  95. GRB 240529A: optical photometry from Konkoly
  96. GRB 240529A: GROWTH-India optical follow-up
  97. GRB 240529A: AKO Optical Afterglow Detection
  98. GRB 240529A: J-band detections with WINTER
  99. GRB 240529A: Skynet Optical Observations
  100. LIGO/Virgo S240527fv: GRANDMA/FRAM-Auger Optical Observations

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