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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"

32706 results found.

  1. GRB 240624A: Swift-BAT refined analysis
  2. Konus-Wind detection of GRB 240619A
  3. Fermi GRB 240625B: Global MASTER-Net observations report
  4. GRB 240624B: CALET Gamma-Ray Burst Monitor detection
  5. GRB 240625A: Fermi GBM Observation
  6. EP240625a: NOT optical counterpart candidate
  7. EP240625a: EP-FXT detection of the X-ray emission
  8. GRB 240624B: GRBAlpha detection
  9. GRB240624A: Fermi GBM Observation
  10. Swift GRB 240624A: Global MASTER-Net observations report
  11. GRB240615A: Gemini-North observations of the BAT and XRT positions
  12. Fermi GRB 240624A: Global MASTER-Net observations report
  13. GRB240615A: Gemini-North observations of the BAT and XRT positions
  14. GRB 240619A: detection of a radio counterpart with AMI-LA
  15. EP240618a: NOT further optical observations
  16. GRB 240619A: J-band detection with WINTER (duplicate submission of GCN 36739)
  17. GRB 240619A: J-band detection with WINTER
  18. LIGO/Virgo/KAGRA S240622h: Updated Sky localization and Source Classification
  19. EP240618a: NOT optical counterpart candidate
  20. LIGO/Virgo/KAGRA S240621em: Updated Sky localization and Source Classification
  21. GRB 240529A: JinShan optical observations
  22. LIGO/Virgo/KAGRA S240621dy: Updated Sky localization and Source Classification
  23. LIGO/Virgo/KAGRA S240621eb: Updated Sky localization and Source Classification
  24. EP240618a: GSP optical upper limit
  25. LIGO/Virgo/KAGRA S240622h: Identification of a GW compact binary merger candidate
  26. LIGO/Virgo/KAGRA S240621em: Identification of a GW compact binary merger candidate
  27. LIGO/Virgo/KAGRA S240621eb: Identification of a GW compact binary merger candidate
  28. LIGO/Virgo/KAGRA S240621dy: Identification of a GW compact binary merger candidate
  29. IPN triangulation of GRB 240615A (short)
  30. X-ray transient EP240618a: Fermi/GBM non-detection
  31. GRB 240619A: GRBAlpha detection
  32. EP240618a: Swift/XRT upper limit
  33. EP240617a: tentative Swift/XRT detection of the afterglow
  34. GRB 240619A: Swift-XRT probable afterglow detection
  35. GRB 240619A: Swift ToO observations
  36. GRB 240619A: CALET Gamma-Ray Burst Monitor detection
  37. GRB 240619C: NuSTAR automated detection of the GRB
  38. GRB 240619A: Fermi GBM Observation
  39. Fermi GBM Sub-Threshold Detection of GRB 240619C
  40. GRB 240619A: GOTO candidate optical afterglow
  41. EP240618a: Abastumani optical observationsEP240618a
  42. GRB 240615A: NOT optical observations
  43. EP240618a: GRANDMA Optical Upper Limits
  44. EP240618a: TRT optical upper limit
  45. Fermi GRB 240619A: Global MASTER-Net observations report
  46. EP240617a: STEP/T80S optical limits
  47. GRB 240615A: possible transient detection from Wendelstein observations
  48. LIGO/Virgo S240615dg: GRANDMA/FRAM-CTA-N Observations
  49. LIGO/Virgo/KAGRA S240615dg: Updated Sky localization
  50. LIGO/Virgo/KAGRA S240618ah: Updated Sky localization
  51. EP240618a: OHP/T193 MISTRAL i' and Y band upper limits
  52. GRB240615A: 1.3m DFOT optical upper limit
  53. EP240617a is likely a GRB event
  54. LIGO/Virgo/KAGRA S240618ah: Identification of a GW compact binary merger candidate
  55. GRB 240615A: J-band upper limits from WINTER
  56. GRB 240615A: Fermi GBM Observation
  57. LIGO/Virgo/KAGRA S240615ea: Updated Sky localization
  58. GRB 240615A: GECAM detection
  59. X-ray transient EP240414a: Chandra late time observation
  60. GRB 240615A: FLWO-1.2m optical upper limits
  61. Fermi GRB 240616A: Global MASTER-Net observations report
  62. Konus-Wind detection of GRB 240615A (short/hard)
  63. GRB 240615A: GOTO optical upper limits
  64. GRB 240615A: Swift ToO observations
  65. GRB 240615A: Swift/BAT-GUANO arcminute localization of a short burst
  66. LIGO/Virgo/KAGRA S240615ea: Identification of a GW compact binary merger candidate
  67. LIGO/Virgo/KAGRA S240615dg: Identification of a GW compact binary merger candidate
  68. GRB 240603A: VZLUSAT-2 detection
  69. GRB 240612A: GRBAlpha detection
  70. Fermi GRB 240612B: Global MASTER-Net observations report
  71. Fermi GRB 240612A: Global MASTER-Net observations report
  72. GRB 240607A: GECAM detection of a bright long burst
  73. Fermi GRB 240611A: Global MASTER-Net observations report
  74. Konus-Wind detection of GRB 240607A
  75. EXO 0748-676: Swift-BAT refined analysis
  76. GRB 240529A: LBT optical detection and late temporal decay
  77. GRB 240529A : MITSuME Akeno optical afterglow detection
  78. Fermi GRB 240610A: Global MASTER-Net observations report
  79. IPN triangulation of GRB 240607A
  80. Fermi GRB 240608A: Global MASTER-Net observations report
  81. Konus-Wind detection of GRB 240606B
  82. Fermi GRB 240607A: Global MASTER-Net observations report
  83. GRB 240529A: NOEMA detection
  84. GRB 240607A: Fermi GBM Observation
  85. GRB 240606B: Fermi GBM Observation
  86. Swift Trigger 1235109: consistent with noise and not astrophysical
  87. GRB 240607A: AstroSat CZTI detection of bright long burst
  88. GRB 240607A: Fermi GBM detection of a very bright burst
  89. GRB 240529A: radio detection with AMI-LA
  90. GRB 240606B: GECAM-B detection a long burst
  91. GRB 240606B: Swift ToO observations
  92. GRB 240606B: Swift/BAT-GUANO arcminute localization of a burst
  93. Konus-Wind detection of GRB 240603A
  94. Fermi GRB 240604A: Global MASTER-Net observations report
  95. IPN triangulation of GRB 240531A (short)
  96. Fermi GRB 240605A: Global MASTER-Net observations report
  97. Fermi GRB 240605C: Global MASTER-Net observations report
  98. LIGO/Virgo/KAGRA S240601co: Updated Sky localization
  99. IPN triangulation of GRB 240603A
  100. GRB 240529A: SAO RAS optical observations

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