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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"

36308 results found.

  1. GRB 241212A: Fermi GBM Final Real-time Localization
  2. GRB 241209B: Mondy AZT-33IK and AbAO AS-32 optical observations
  3. GRB 241209A: Chandra X-ray Detection
  4. Konus-Wind detection of GRB 241209B
  5. GRB 241207A: EIRSAT-1 GMOD Detection
  6. GRB 241209A: Redshift of the likely host galaxy z = 0.784 from OSIRIS+/GTC
  7. GRB 241209B: GRBAlpha detection
  8. GRB 241206C: GRBAlpha detection
  9. GRB 241211A: Fermi GBM Final Real-time Localization
  10. GRB 241129A: Fermi GBM Observation
  11. GRB 241209B: Swift/BAT-GUANO localization skymap of a burst
  12. GRB 241209D: REM optical/NIR upper limits
  13. Konus-Wind detection of GRB 241209D
  14. GRB 241209B: Swift-XRT afterglow detection
  15. GRB 241209C: Fermi GBM Observation
  16. GRB 241209A: Swift-XRT refined Analysis
  17. Fermi Gamma-ray Burst Monitor trigger 755485387 / 241210044 is not a GRB
  18. GRB 241128A: CrAO ZTSh and Mondy AZT-33IK optical observations
  19. GRB 241209D: AstroSat CZTI detection
  20. GRB 241209A: EP-FXT follow-up observations
  21. GRB 241209B: SVOM/VT afterglow detection
  22. GRB 241207B: Fermi GBM Observation
  23. GRB 241209A: BOOTES-7 and 2.2m CAHA early optical upper limits
  24. GRB 241209D: Swift-XRT refined Analysis
  25. GRB 241209D: Fermi GBM Observation
  26. GRB 241209A: VLT/HAWK-I near-IR counterpart candidate
  27. GRB 241209D: COLIBRÍ detection of the afterglow
  28. GRB 241209A: COLIBRÍ Optical Upper Limit
  29. Fermi GRB 241209D: Global MASTER-Net observations report
  30. GRB 241209A: Fermi GBM Observation
  31. GRB 241209C: Swift/BAT-GUANO localization skymap of a burst
  32. GRB 241209A: GRANDMA/TAROT upper limit
  33. GRB 241209B: BOOTES-5 optical upper limit
  34. Swift GRB 241209D: Global MASTER-Net observations report
  35. Fermi GRB 241209C: Global MASTER-Net observations report
  36. Fermi GRB 241209E: Global MASTER-Net observations report
  37. GRB 241209E: Fermi GBM Final Real-time Localization
  38. GRB 241209B: Swift ToO observations
  39. GRB 241209A: REM optical/NIR observations
  40. GRB 241209D: Enhanced Swift-XRT position
  41. GRB 241209C: AstroSat CZTI detection
  42. GRB 241209D: Swift detection of a burst
  43. GRB 241209D: Fermi GBM Final Real-time Localization
  44. GRB 241209A: VLT/X-shooter spectroscopy
  45. GRB 241209A: Enhanced Swift-XRT position
  46. GRB 241114B: cubesat Avion detection
  47. GRB 241209A: VLT optical observations
  48. Fermi GRB 241209A: Global MASTER-Net observations report
  49. GRB 241209C: Fermi GBM Final Real-time Localization
  50. GRB 241209A: GOTO optical upper limits
  51. GRB 241209A: Prompt enhanced Swift-XRT position
  52. GRB 241209B: SVOM/ECLAIRs and GRM detection of a long burst
  53. GRB 241209A: Swift detection of a short burst
  54. GRB 241209A: Fermi GBM Final Real-time Localization
  55. Fermi GRB 241207B: Global MASTER-Net observations report
  56. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  57. Fermi Gamma-ray Burst Monitor trigger 755277791/241207641 is not a GRB
  58. GRB 241201A: AstroSat CZTI detection
  59. GRB 241206A: DDOTI Upper Limit on the Afterglow
  60. GRB 241207C: MASTER optical observations
  61. GRB 241207C: Tiled Swift observations
  62. GRB 241207C: MAXI/GSC detection
  63. GRB 241207B: Fermi GBM Final Real-time Localization
  64. Fermi GRB 241207A: Global MASTER-Net observations report
  65. GRB 241206A: Fermi GBM observation
  66. GRB 241206C: SVOM/GRM observation of a likely short burst
  67. GRB 241207A: Fermi GBM Final Real-time Localization
  68. GRB 241206A: Swift/BAT-GUANO localization skymap of a burst
  69. GRB 241206B: SVOM/MXT observations: a probable flare from the QSO 1ES 1959+650
  70. GRB 241206B: GWAC-F50A optical upper limit
  71. GRB 241206B: SVOM/ECLAIRs detection of a long soft transient
  72. Fermi GRB 241206A: Global MASTER-Net observations report
  73. GRB 241206A: Fermi GBM Final Real-time Localization
  74. GRB 241204A: COLIBRÍ Optical Upper Limit
  75. EP241202b: KAIT optical upper limit
  76. LIGO/Virgo/KAGRA S241125n: gamma-ray upper limits from joint observations by the LST-1 and MAGIC telescopes
  77. GRB 241204A: DDOTI Upper Limits on the Afterglow
  78. GRB 241204A: Fermi GBM Observation
  79. Fermi GRB 241204A: Global MASTER-Net observations report
  80. GRB 241130A: CALET Gamma-Ray Burst Monitor detection
  81. GRB 241128A : RAPAS follow-up observations
  82. GRB 241201A: GRBAlpha detection
  83. GRB 241204A: Fermi-LAT detection
  84. EP241202b: Upper limits from Fermi-GBM Observations
  85. Fermi-GBM Sub-Threshold Detection of GRB 241128A
  86. GRB 241113B : RAPAS follow-up observation
  87. Konus-Wind detection of GRB 241130A
  88. EP241201a: BOOTES-5 optical upper limit
  89. IPN triangulation of GRB 241130A
  90. GRB 241130A: EIRSAT-1 GMOD Detection
  91. GRB 241128A: Swift/UVOT Upper Limits
  92. GRB 241130A: Fermi GBM Detection
  93. IceCube-241127A: Upper limits from a search for additional neutrino events in IceCube
  94. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  95. LIGO/Virgo/KAGRA S241102br: GRAWITA wide-field optical observations
  96. GRB 241127B: detection of a long GRB by SVOM/ECLAIRs
  97. GRB241201B: Fermi GBM Final Localization
  98. GRB241201B: Fermi GBM Final Localization
  99. Fermi GRB 241201A: Global MASTER-Net observations report
  100. GRB 241201A: BALROG localization (Fermi Trigger 754757764 / GRB 241201622)

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