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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"

21474 results found.

  1. GRB 231118A: REM optical afterglow detection
  2. GRB 231122B: AstroSat CZTI detection
  3. GRB 231122B: CALET Gamma-Ray Burst Monitor detection
  4. GRB 231122B: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  5. GRB 231117A: Chandra afterglow detection
  6. GRB 231118A: ATCA detection of radio counterpart
  7. GRB 231117A: Swift/UVOT late time observations
  8. GRB 231117A: Swift-BAT refined analysis
  9. GRB 231118A: GRBAlpha detection
  10. LIGO/Virgo/KAGRA S231118d: Upper limits from Swift/BAT-GUANO
  11. LIGO/Virgo/KAGRA S231118an: Upper limits from Swift/BAT-GUANO
  12. LIGO/Virgo/KAGRA S231114n: Upper limits from Swift/BAT-GUANO
  13. LIGO/Virgo/KAGRA S231113bb: Upper limits from Swift/BAT-GUANO
  14. GRB 231118A: VZLUSAT-2 detection
  15. GRB 231118A: Swift-BAT refined analysis
  16. GRB 231117A: CALET Gamma-Ray Burst Monitor detection
  17. 231118A: Swift-UVOT Detection
  18. GRB231117A: Swift-UVOT detection
  19. GRB 231118A: Fermi GBM observation
  20. GRB 231117A: Swift-XRT refined Analysis
  21. GRB 231118A: Swift-XRT refined Analysis
  22. GRB 231118A: MeerLICHT afterglow detection
  23. GRB 231118A: VLT/X-shooter redshift
  24. GRB 231117A: MAAO 0.7-m telescope optical upper limit
  25. GRB 231117A: GECAM-C detection
  26. GRB 231118A: AstroSat CZTI detection
  27. GRB 231115A: Upper limit from CALET Gamma-Ray Burst Monitor
  28. GRB 231118A: Las Cumbres optical detection
  29. GRB 231118A: LCOGT Optical Observations
  30. GRB 231118A: MASTER OT observation
  31. Swift GRB231118.72: Global MASTER-Net observations report
  32. GRB 231118A: Enhanced Swift-XRT position
  33. GRB 231117A: Kinder observations with Lulin observatory for AT 2023yba without fading in r band
  34. GRB 231118A: Swift-XRT position
  35. GRB 231118A: Skynet Optical Afterglow Discovery
  36. GRB 231118A: Swift detection of a burst
  37. GRB 231117A: ATCA detection of a radio counterpart
  38. GRB 231117A: GRBAlpha detection
  39. GRB 231117A: GIT optical follow-up
  40. GRB 231117A: Keck observations indicate presence of optical afterglow in z~0.3-0.5 galaxy
  41. GRB 231117A: REM optical and NIR early-time observations
  42. GRB 231117A: AKO Optical Upper Limit
  43. GRB 231117A: afterglow candidate detection from Kinder observations with Lulin observatory
  44. Swift GRB 231117A: Global MASTER-Net observations report
  45. GRB 231117A (short): Glowbug gamma-ray detection
  46. GRB 231117A: ATLAS non-detection of an optical counterpart
  47. Konus-Wind detection of GRB 231117A (short/hard)
  48. GRB 231115A: optical observations from INAF observatories
  49. GRB 231117A : MITSuME Akeno optical upper limits
  50. GRB 231117A: AGILE detection of a bright short burst
  51. GRB 231117A: Enhanced Swift-XRT position
  52. GRB 231117A: GOTO optical upper limits
  53. GRB 231117A: AstroSat CZTI detection of a bright short burst
  54. GRB 231117A: Swift detection of a bright short burst
  55. GRB 231111A: Swift/UVOT Detection
  56. GRB 231115A: Swift/BAT-GUANO detection of a short burst
  57. GRB 231115A: Swift-XRT and Swift-UVOT observations
  58. GRB 231115A: Swift ToO observations
  59. GRB 231111A: Swift-BAT refined analysis
  60. GECAM-B observation of a short burst from SGR J1555-5402
  61. SGRJ1555-5402: Swift/BAT-GUANO arcminute localization of a SGR flare
  62. GRB 231110A: CALET Gamma-Ray Burst Monitor detection
  63. GRB 231110A: Swift-BAT refined analysis
  64. GRB231111A: MDM 2.4m Hiltner Telescope Observation
  65. GRB 231111A: Xinglong-2.16m optical observations
  66. GRB 231110A: Swift-UVOT Upper Limits
  67. GRB 231104A: VZLUSAT-2 detection
  68. GRB 231110A: Glowbug gamma-ray detection
  69. GRB 231110A: AstroSat CZTI detection
  70. GRB 231111A NUTTelA-TAO / BSTI Early Measurements
  71. GRB 231111A: Leavitt Observatory optical observations
  72. GRB231111A: Optical follow-up observations with Mephisto
  73. GRB 231111A: Osservatorio Astronomico "Nastro Verde" optical observations with detection of an optical counterpart
  74. GRB 231110A: Terskol Zeiss-2000 optical upper limit
  75. GRB 231111A: Swift-XRT refined Analysis
  76. GRB 231111A: Mondy optical observations
  77. GRB 231111A: GECAM-C detection of a long burst (correction)
  78. GRB 231110A: GECAM-B detection (correction)
  79. GRB 231111A: Enhanced Swift-XRT position
  80. GRB 231111A: GECAM-C detection of a long burst
  81. GRB 231110A: GECAM detection
  82. GRB 231110A: SAO RAS optical observations
  83. GRB 231110A: Swift-XRT afterglow detection
  84. GRB231111A: YAHPT Observations
  85. GRB231111A: GIT confirmation of the optical afterglow
  86. GRB 231111A: MASTER OT earlier detection
  87. GRB 231111A: Nanshan/HMT optical observations
  88. GRB 231111A: Swift detection of a burst with an optical counterpart
  89. Swift GRB231111.60: Global MASTER-Net observations report
  90. GRB231110A: WFST Observation and upper limits
  91. Swift GRB231110.89: Global MASTER-Net observations report
  92. GRB 231110A: Swift detection of a burst
  93. GRB 231104A: Swift-BAT refined analysis
  94. GRB 231104A: FRAM-ORM optical limit
  95. LIGO/Virgo/KAGRA S231102w: Upper limits from Swift/BAT-GUANO
  96. GRB 231104A: Wendelstein Optical/Infrared Observations
  97. GRB 231104A: NuSTAR Observation of the prompt emission
  98. GRB 231104A: 3.6m DOT optical upper limit
  99. GRB 231104A: NOT upper limit
  100. GRB 231104A: Fermi GBM Observation

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