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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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.

Advanced Search Examples (click to copy):

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

12402 results found.

  1. GRB 240712A: Swift/UVOT Upper Limits
  2. GRB 240713A: J-band upper limit from WINTER
  3. GRB 240713A: NOT optical upper limits on three EP/FXT candidates
  4. GRB 240713A: JinShan optical upper limits
  5. GRB 240713A: OHP/T120 optical upper limit
  6. GRB240713A: Optical upper limit with Kinder observations
  7. GRB240713A: TAROT and GRANDMA Observations of SVOM/ECLAIRs GRB240713A
  8. EP240708a: GSP optical upper limit
  9. GRB 240712A: Swift detection of a burst
  10. LIGO/Virgo/KAGRA S240711cm: Coverage and upper limits from MAXI/GSC observations
  11. Fermi trigger No 742405878: Global MASTER-Net observations report
  12. Fermi trigger No 742317942: Global MASTER-Net observations report
  13. EP240708a: KAIT optical upper limit
  14. Fermi GRB 240710A: Global MASTER-Net observations report
  15. EP240708a: SVOM/C-GFT optical upper limit
  16. EP240708a: X-ray follow-up observations with EP/FXT and Swift/XRT
  17. EP240708a: Optical upper limits with Kinder observations
  18. LIGO/Virgo S240615dg: Swift XRT observations, 28 futher X-ray sources
  19. EP240703b: GSP optical upper limit
  20. EP240703b: TRT optical upper limits
  21. EP240702a: TRT optical upper limits
  22. EP240703a and EP240703b: Swift/XRT upper limits
  23. EP240703a: KAIT optical upper limit
  24. EP240703a: BTA observations
  25. EP240703c: Kinder optical follow-up and Swift XRT observations
  26. EP240703a: BOOTES-3 optical upper limit
  27. EP240703a: Kinder optical follow-up observations
  28. LIGO/Virgo/KAGRA S240422ed: Updated significance estimate
  29. The first three GRBs detected by SVOM: X-ray Upper Limits from EP-WXT
  30. EP240702a: Swift/XRT upper limit
  31. EP240702a: GSP optical upper limit
  32. Fermi GRB 240702A: Global MASTER-Net observations report
  33. LIGO/Virgo/KAGRA S240627by: Upper limits from Swift/BAT-GUANO
  34. Fermi trigger No 741448122: Global MASTER-Net observations report
  35. LIGO/Virgo/KAGRA S240629by: Upper limits from Fermi-GBM Observations
  36. LIGO/Virgo/KAGRA S240629by: Coverage and upper limits from MAXI/GSC observations
  37. Fermi trigger No 741356809: Global MASTER-Net observations report
  38. Fermi GRB 240629A: Global MASTER-Net observations report
  39. Fermi trigger No 741296200: Global MASTER-Net observations report
  40. Fermi trigger No 741251380: Global MASTER-Net observations report
  41. IceCube-Cascade 240626A: Upper limits from a search for additional neutrino events in IceCube
  42. Fermi trigger No 741211696: Global MASTER-Net observations report
  43. EP240626a: Montarrenti Observatory optical upper limit
  44. EP240626a: KAIT optical upper limit
  45. EP240625a: GRANDMA Optical Upper Limits
  46. Konus-Wind detection of GRB 240619A
  47. EP240626a: BOOTES-7 optical upper limit
  48. Fermi GRB 240625B: Global MASTER-Net observations report
  49. LIGO/Virgo/KAGRA S240622h: Upper limits from Swift/BAT-GUANO
  50. LIGO/Virgo/KAGRA S240621dy: Upper limits from Swift/BAT-GUANO
  51. LIGO/Virgo/KAGRA S240618ah: Upper limits from Swift/BAT-GUANO
  52. Swift GRB 240624A: Global MASTER-Net observations report
  53. GRB240615A: Gemini-North observations of the BAT and XRT positions
  54. Fermi GRB 240624A: Global MASTER-Net observations report
  55. Fermi trigger No 740949590: Global MASTER-Net observations report
  56. GRB240615A: Gemini-North observations of the BAT and XRT positions
  57. Fermi trigger No 740744838: Global MASTER-Net observations report
  58. EP240618a: GSP optical upper limit
  59. X-ray transient EP240618a: Fermi/GBM non-detection
  60. EP240618a: Swift/XRT upper limit
  61. EP240618a: Abastumani optical observationsEP240618a
  62. EP240618a: GRANDMA Optical Upper Limits
  63. EP240618a: TRT optical upper limit
  64. Fermi trigger No 740474239: Global MASTER-Net observations report
  65. Fermi GRB 240619A: Global MASTER-Net observations report
  66. GRB 240615A: possible transient detection from Wendelstein observations
  67. EP240618a: OHP/T193 MISTRAL i' and Y band upper limits
  68. EP240618a: BOOTES-6/DPRT optical upper limit
  69. LIGO/Virgo S240615dg: Swift XRT observations, 39 X-ray sources
  70. Fermi trigger No 740430582: Global MASTER-Net observations report
  71. GRB240615A: 1.3m DFOT optical upper limit
  72. EP240617a: BOOTES-6/DPRT optical upper limit
  73. LIGO/Virgo/KAGRA S240615ea: Upper limits from Swift/BAT-GUANO
  74. LIGO/Virgo/KAGRA S240615dg: Upper limits from Swift/BAT-GUANO
  75. GRB 240615A: J-band upper limits from WINTER
  76. GRB 240615A: Swift-XRT observations
  77. X-ray transient EP240414a: Chandra late time observation
  78. GRB 240615A: FLWO-1.2m optical upper limits
  79. Fermi trigger No 740221779: Global MASTER-Net observations report
  80. Fermi GRB 240616A: Global MASTER-Net observations report
  81. Konus-Wind detection of GRB 240615A (short/hard)
  82. GRB 240615A: GOTO optical upper limits
  83. Fermi trigger No 740166710: Global MASTER-Net observations report
  84. Fermi GRB 240612B: Global MASTER-Net observations report
  85. Fermi GRB 240612A: Global MASTER-Net observations report
  86. Fermi GRB 240611A: Global MASTER-Net observations report
  87. GRB 240529A : MITSuME Akeno optical afterglow detection
  88. Trigger 1236151: Swift detection of EXO 0748-676
  89. Fermi GRB 240610A: Global MASTER-Net observations report
  90. Fermi trigger No 739632045: Global MASTER-Net observations report
  91. Fermi GRB 240608A: Global MASTER-Net observations report
  92. Fermi trigger No 739506569: Global MASTER-Net observations report
  93. Fermi GRB 240607A: Global MASTER-Net observations report
  94. Swift Trigger 1235109: consistent with noise and not astrophysical
  95. Fermi trigger No 739373591: Global MASTER-Net observations report
  96. GRB 240606B: Swift-XRT afterglow detection
  97. Swift GRB240606.15: Global MASTER-Net observations report
  98. Fermi GRB 240604A: Global MASTER-Net observations report
  99. Fermi GRB 240605A: Global MASTER-Net observations report
  100. Fermi GRB 240605C: Global MASTER-Net observations report

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