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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"

32746 results found.

  1. SGR 1E 1841-045 / Kes 73: SVOM/GRM observation
  2. GRB 240825A: Swift/UVOT Detection
  3. GRB 240825A: REM detection of the optical/NIR afterglow
  4. GRB 240825A: VLT/X-shooter redshift
  5. GRB 240825A: SVOM/C-GFT optical observations
  6. GRB 240825A: Montarrenti Observatory optical observations
  7. GRB 240825A: MASTER optical counterpart observation
  8. GRB 240825A: Fermi-LAT detection
  9. GRB 240825A: LCO optical observations
  10. GRB 240824B: KAIT optical upper limit
  11. SGR 1E 1841-045 / Kes 73 (Trigger 1249878): Osservatorio Atronomico Nastro Verde optical upper limit
  12. GRB 240824B: Fermi GBM Observation
  13. Fermi GRB 240825A: Global MASTER-Net observations report
  14. SGR 1E 1841-045 / Kes 73 (Trigger 1249653) - Osservatorio Astronomico Nastro Verde upper limit
  15. GRB 240824B: NOT optical upper limit
  16. GRB 240825A: GMG Optical Observation
  17. Swift GRB 240825A: Global MASTER-Net observations report
  18. GRB 240825A: 1.6m Mephisto multi-band detection
  19. GRB 240825A: AKO Optical Afterglow Detection
  20. GRB 240825A: Skynet Optical Afterglow observations
  21. GRB 240825A: Nanshan/HMT optical afterglow observations
  22. GRB 240824A: Swift-BAT refined analysis
  23. GRB 240824A: SVOM/C-GFT optical upper limit
  24. GRB 240824B: Swift-XRT afterglow detection
  25. LIGO/Virgo/KAGRA S240825ar: Identification of a GW compact binary merger candidate
  26. GRB 240824B: Swift/BAT arcminute localization of a burst
  27. GRB 240824B: Swift ToO observations
  28. Fermi GRB 240824C: Global MASTER-Net observations report
  29. GRB 240824A: Swift/UVOT Upper Limits
  30. GRB 240821A: Swift/UVOT observations of the XRT sources.
  31. GRB 240824B: MAXI/GSC detection
  32. GRB 240824A: Retraction of GCN 37255
  33. GRB240824A: GRANDMA/TAROT-TCA Upper Limit
  34. SGR 1E 1841-045 / Kes 73: Leavitt Observatory optical upper limit
  35. GRB 240824A: KAIT optical upper limit
  36. SGR 1E 1841-045 / Kes 73: Montarrenti Observatory optical upper limits
  37. GRB 240821A: Colibri Optical Upper Limit
  38. EP240820a: PRIME J-band Observations
  39. GRB 240821A: Swift-XRT observations
  40. GRB 240821A: REM optical/NIR upper limits
  41. GRB 240821A: LCO optical observations
  42. GRB 240821A: JinShan optical upper limits
  43. GRB 240809A: Mondy and AbAO Optical Observations
  44. GRB 240821A: SVOM/VT follow-up and optical upper limit
  45. GRB 240821A: GMG Optical Upper Limit
  46. Fermi GRB 240821A: Global MASTER-Net observations report
  47. GECAM-B observation of a short burst from SGR 1E 1841-045 / Kes 73
  48. GRB 240821A: Fermi GBM Observation
  49. GRB 240821A: Swift ToO observations
  50. Fermi-GBM Observations of the reactivation of SGR 1E 1841-045 / Kes 73
  51. GRB240821A: EIRSAT-1 GMOD Detection
  52. GRB240821B: First GRB Detected by EIRSAT-1 GMOD
  53. GRB 240821A: EP-FXT follow-up observation and afterglow candidates
  54. Fermi GRB 240821B: Global MASTER-Net observations report
  55. EP240801a: Keck/LRIS spectroscopic redshift confirmation
  56. GRB 240821A: SVOM/GRM observation
  57. GRB 240821A: SVOM/GRM observation
  58. GRB 240821A: GRANDMA/LesMakes-T60 Upper Limit
  59. Trigger 1249878: Swift detection of another burst from SGR 1E 1841-045 / Kes 73
  60. GRB 240821A : a likely short GRB detected by SVOM/ECLAIRs
  61. GRB 240819A: Swift-XRT observations
  62. GRB 240819A: JinShan optical upper limits on one Swift/XRT source
  63. EP240820a: TRT optical upper limit
  64. GRB 240819A: KAIT optical upper limit
  65. EP240816a: PRIME upper limits
  66. GRB 240819A : an X-ray transient detected by SVOM/ECLAIRs
  67. GRB 240819A: TRT optical upper limits on the Swift/XRT and EP/FXT sources
  68. GRB 240819A: Swift ToO observations
  69. GRB 240814A: SVOM/GRM observation
  70. EP240816b: Liverpool Telescope optical follow-up observations
  71. GRB 240814C: SVOM/GRM observation
  72. IceCube-240721A: AT2023qqp and AT2024pge likely unrelated
  73. GRB GRB 240809A: Osservatorio Astronomico "Nastro Verde" optical observations: detection of an optical counterpart
  74. GRB 240805B: Osservatorio Astronomico Nastro Verde upper limit
  75. EP240816b: KAIT optical upper limit
  76. GRB 240814B: GRBAlpha detection
  77. EP EP240816b: Global MASTER-Net observations report
  78. EP240816b: TRT optical upper limit
  79. Fermi GRB 240814A: Global MASTER-Net observations report
  80. Fermi GRB 240814C: Global MASTER-Net observations report
  81. Fermi GRB 240814B: Global MASTER-Net observations report
  82. GRB 240812B: SVOM/GRM observation
  83. EP240802a: Kinder optical, SWIFT-UVOT, and SWIFT-XRT upper limits 6 days after the WXT detection
  84. LIGO/Virgo/KAGRA S240813d: Updated Sky localization
  85. Konus-Wind detection of GRB 240811A
  86. Konus-Wind detection of GRB 240810A
  87. LIGO/Virgo/KAGRA S240813d: Identification of a GW compact binary merger candidate
  88. LIGO/Virgo/KAGRA S240813c: Updated Sky localization
  89. LIGO/Virgo/KAGRA S240813c: Identification of a GW compact binary merger candidate
  90. GRB 240809A: Correction to the VLA source position in GCN 37158
  91. GRB 240810A: SVOM/GRM observation
  92. GRB 240809A: ATA radio non-detection
  93. GRB 240809A : RAPAS follow-up observations
  94. GRB 240809A: VLA detection
  95. GRB 240809A: ALMA detection
  96. IPN triangulation of GRB 240810A (short)
  97. GRB 240811A: Swift-BAT refined analysis
  98. GRB 240809A: Swift-BAT refined analysis
  99. EP240807a: PRIME H-band upper limits
  100. IceCube-240808A: Upper limits from a search for additional neutrino events in IceCube

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