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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"

28261 results found.

  1. GRB 241215A: A long GRB detected by INTEGRAL
  2. Integral GRB241215.58: Global MASTER-Net observations report
  3. GRB 241213B: Swift-XRT observations
  4. GRB 241213A: Swift/UVOT Upper Limits
  5. GRB 241213A: Swift-XRT refined Analysis
  6. GRB 241212A: Fermi GBM detection
  7. EP241208a: NOT optical upper limits
  8. GRB 241213A: LCOGT Optical Upper Limits
  9. GRB 241213B: MAXI/GSC detection
  10. EP241213a: EP detection of An X-ray Transient
  11. GRB 241213A: REM optical/NIR upper limits
  12. GRB 241213A: Enhanced Swift-XRT position
  13. GRB241212A: OHP/T193 optical observations
  14. GRB 241213A: SAO RAS optical upper limit
  15. LIGO/Virgo/KAGRA S241210fu: Updated Sky localization
  16. GRB 241213A: Swift detection of a burst
  17. GRB 241212A : SVOM/C-GFT optical upper limit at early phase
  18. GRB 241212A: AstroSat CZTI detection
  19. GRB 241209B: GRANDMA/TRT upper limit
  20. GRB 241207A: TSHAO Zeiss-1000 optical observations
  21. GRB 241212A: SVOM detection of a bright long burst
  22. GRB 241207A: EIRSAT-1 GMOD Detection
  23. LIGO/Virgo/KAGRA S241210cw: Updated Sky localization
  24. LIGO/Virgo/KAGRA S241210d: Updated Sky localization and EM Bright Classification
  25. GRB 241129A: Fermi GBM Observation
  26. GRB 241209B: Swift/BAT-GUANO localization skymap of a burst
  27. GRB 241209D: REM optical/NIR upper limits
  28. GRB 241209B: Swift-XRT afterglow detection
  29. GRB 241209C: Fermi GBM Observation
  30. GRB 241209A: Swift-XRT refined Analysis
  31. LIGO/Virgo/KAGRA S241210fu: Identification of a GW compact binary merger candidate
  32. EP241208a: Optical upper limit with Kinder observations
  33. GRB 241209B: SVOM/VT afterglow detection
  34. LIGO/Virgo/KAGRA S241210cw: Identification of a GW compact binary merger candidate
  35. LIGO/Virgo/KAGRA S241210d: Identification of a GW compact binary merger candidate
  36. GRB 241207B: Fermi GBM Observation
  37. GRB 241209D: Swift-XRT refined Analysis
  38. GRB 241209D: Fermi GBM Observation
  39. GRB 241209A: VLT/HAWK-I near-IR counterpart candidate
  40. GRB 241209D: COLIBRÍ detection of the afterglow
  41. GRB 241209A: COLIBRÍ Optical Upper Limit
  42. GRB 241209C: Swift/BAT-GUANO localization skymap of a burst
  43. GRB 241209A: GRANDMA/TAROT upper limit
  44. GRB 241209A: REM optical/NIR observations
  45. GRB 241209D: Enhanced Swift-XRT position
  46. GRB 241209D: Swift detection of a burst
  47. GRB 241209A: Enhanced Swift-XRT position
  48. GRB 241114B: cubesat Avion detection
  49. GRB 241209A: VLT optical observations
  50. GRB 241209A: GOTO optical upper limits
  51. GRB 241209B: SVOM/ECLAIRs and GRM detection of a long burst
  52. EP241208a: EP detection of a fast X-ray transient
  53. GRB 241209A: Swift detection of a short burst
  54. Fermi GRB 241207B: Global MASTER-Net observations report
  55. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  56. GRB 241206A: DDOTI Upper Limit on the Afterglow
  57. AT2024adec: X-ray Upper Limits from EP-FXT Observation
  58. GRB 241207C: MAXI/GSC detection
  59. EP241206a: EP detection of a fast X-ray transient
  60. GRB 241206A: Fermi GBM observation
  61. GRB 241206A: Swift/BAT-GUANO localization skymap of a burst
  62. EP241201a: 1.6m Mephisto Optical Upper Limits
  63. GRB 241204A: COLIBRÍ Optical Upper Limit
  64. EP241202b: KAIT optical upper limit
  65. LIGO/Virgo/KAGRA S241125n: gamma-ray upper limits from joint observations by the LST-1 and MAGIC telescopes
  66. GRB 241204A: DDOTI Upper Limits on the Afterglow
  67. GRB 241130A: CALET Gamma-Ray Burst Monitor detection
  68. GRB 241128A : RAPAS follow-up observations
  69. EP241202b: Upper limits from Fermi-GBM Observations
  70. IceCube-241127A: No transient candidates from the Zwicky Transient Facility
  71. EP241202b: Kinder optical counterpart candidate
  72. Fermi-GBM Sub-Threshold Detection of GRB 241128A
  73. GRB 241113B : RAPAS follow-up observation
  74. Konus-Wind detection of GRB 241130A
  75. EP241201a: BOOTES-5 optical upper limit
  76. EP241202b: EP detection of a fast X-ray transient
  77. EP241201a: NOT optical observations
  78. IPN triangulation of GRB 241130A
  79. GRB 241130A: EIRSAT-1 GMOD Detection
  80. GRB 241128A: Swift/UVOT Upper Limits
  81. GRB 241130A: Fermi GBM Detection
  82. IceCube-241127A: Upper limits from a search for additional neutrino events in IceCube
  83. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  84. EP241201a: Kinder optical counterpart candidate
  85. LIGO/Virgo/KAGRA S241102br: GRAWITA wide-field optical observations
  86. LIGO/Virgo/KAGRA S241201ac: Updated Sky localization
  87. GRB 241201A: BALROG localization (Fermi Trigger 754757764 / GRB 241201622)
  88. EP241126a: 1.6m Mephisto Optical Upper Limits
  89. GRB 241201A: Fermi GBM Final Real-time Localization
  90. LIGO/Virgo/KAGRA S241201ac: Identification of a GW compact binary merger candidate
  91. LIGO/Virgo/KAGRA S241130be: Updated Sky localization
  92. Fermi trigger No 754701230: Global MASTER-Net observations report
  93. LIGO/Virgo/KAGRA S241130n: Updated Sky localization
  94. LIGO/Virgo/KAGRA S241125n: GRANDMA Optical Upper Limits
  95. GRB 241128A: AbAO optical upper limit
  96. LIGO/Virgo/KAGRA S241127aj: Updated Sky localization
  97. LIGO/Virgo/KAGRA S241130be: Identification of a GW compact binary merger candidate
  98. LIGO/Virgo/KAGRA S241129aa: Updated Sky localization
  99. LIGO/Virgo/KAGRA S241130n: Identification of a GW compact binary merger candidate
  100. GRB 241128A: Swift-BAT refined analysis

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