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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"

21526 results found.

  1. GRB 231205B: AGILE detection
  2. GRB 231205B: Ondrejov D50 optical upper limit
  3. GRB 231205B: Swift-XRT refined Analysis
  4. GRB 231205B: REM optical/NIR upper limits
  5. GRB 231129C: ASIM MXGS observation and localization
  6. GRB 231205B: NUTTelA-TAO / BSTI Early Optical Limits
  7. GRB 231205B: r'-band observations from MISTRAL at Observatoire de Haute-Provence
  8. GRB 231205B : MITSuME Akeno optical upper limits
  9. GRB 231205B: Zadko observatory - Gingin optical observations
  10. GRB 231205B: Gaoyazi/GOT optical upper limit
  11. GRB 231205B: Nanshan/HMT optical upper limit
  12. GRB 231205B: GECAM-B detection of a long burst
  13. GRB 231205B: LCOGT Optical Upper Limits
  14. GRB 231205B: Enhanced Swift-XRT position
  15. Swift GRB231205.70: Global MASTER-Net observations report
  16. GRB 231205B: AKO Optical Upper Limit
  17. GRB 231205B: Swift detection of a burst
  18. LIGO/Virgo/KAGRA S231129ac: Upper limits from Swift/BAT-GUANO
  19. GRB 231203A: Fermi GBM Observation
  20. GRB 231203A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  21. Konus-Wind detection of GRB 231129C
  22. GRB 231129C: Swift-XRT afterglow detection
  23. GRB 231129C: PROMPT optical upper limits for the MAXI/GSC X-ray counterpart and the MASTER afterglow candidate
  24. GRB 231129A: VZLUSAT-2 detection
  25. GRB 231129B: Swift-XRT observations
  26. GRB 231129C: AGILE detection
  27. GRB 231129A : MITSuME Akeno optical upper limits
  28. GRB 231129C: Swift/BAT-GUANO localization of a burst outside the coded FOV
  29. GRB 231129A: Swift-BAT refined analysis
  30. GRB 231129C: MASTER OT detection
  31. GRB 231129A: BOOTES-5/JGT optical upper limit
  32. GRB 231129A: JinShan optical upper limit
  33. GRB 231129C: Swift-XRT observations
  34. GRB 231129A: Swift/UVOT Upper Limits
  35. GRB 231129A: optical upper limit in Mondy observatory
  36. GRB 231129C: Tiled Swift observations
  37. GRB 231129A: Enhanced Swift-XRT position
  38. GRB 231129A: Swift-XRT refined Analysis
  39. GRB 231129B: Tiled Swift observations
  40. GRB 231129A: GECAM-C detection of a long burst
  41. GRB 231129A: INTEGRAL detection of a long GRB
  42. GRB 231129A: Swift detection of a burst
  43. GRB 231123C: Fermi GBM Observation
  44. GRB 231123B: Fermi GBM Observation
  45. GRB 231123B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  46. GRB 231111A: Optical follow-up observations at Terskol, AbAO, Maidanak, Mondy, Assy
  47. GRB 231123C: Insight-HXMT/HE detection
  48. GRB 231123C (short): Glowbug gamma-ray detection
  49. GRB230728A: VIRT optical upper limit
  50. GRB230506B: VIRT optical upper limit
  51. GRB 231123C: Swift/BAT-GUANO detection of a short burst likely outside the coded FOV
  52. GRB 231115A: XMM-Newton observation
  53. GRB 231118A: REM optical afterglow detection
  54. GRB 231122B: AstroSat CZTI detection
  55. GRB 231122B: CALET Gamma-Ray Burst Monitor detection
  56. GRB 231122B: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  57. GRB 231117A: Chandra afterglow detection
  58. GRB 231118A: ATCA detection of radio counterpart
  59. GRB 231117A: Swift/UVOT late time observations
  60. GRB 231117A: Swift-BAT refined analysis
  61. GRB 231118A: GRBAlpha detection
  62. LIGO/Virgo/KAGRA S231118d: Upper limits from Swift/BAT-GUANO
  63. LIGO/Virgo/KAGRA S231118an: Upper limits from Swift/BAT-GUANO
  64. LIGO/Virgo/KAGRA S231114n: Upper limits from Swift/BAT-GUANO
  65. LIGO/Virgo/KAGRA S231113bb: Upper limits from Swift/BAT-GUANO
  66. GRB 231118A: VZLUSAT-2 detection
  67. GRB 231118A: Swift-BAT refined analysis
  68. GRB 231117A: CALET Gamma-Ray Burst Monitor detection
  69. 231118A: Swift-UVOT Detection
  70. GRB231117A: Swift-UVOT detection
  71. GRB 231118A: Fermi GBM observation
  72. GRB 231117A: Swift-XRT refined Analysis
  73. GRB 231118A: Swift-XRT refined Analysis
  74. GRB 231118A: MeerLICHT afterglow detection
  75. GRB 231118A: VLT/X-shooter redshift
  76. GRB 231117A: MAAO 0.7-m telescope optical upper limit
  77. GRB 231117A: GECAM-C detection
  78. GRB 231118A: AstroSat CZTI detection
  79. GRB 231115A: Upper limit from CALET Gamma-Ray Burst Monitor
  80. GRB 231118A: Las Cumbres optical detection
  81. GRB 231118A: LCOGT Optical Observations
  82. GRB 231118A: MASTER OT observation
  83. Swift GRB231118.72: Global MASTER-Net observations report
  84. GRB 231118A: Enhanced Swift-XRT position
  85. GRB 231117A: Kinder observations with Lulin observatory for AT 2023yba without fading in r band
  86. GRB 231118A: Swift-XRT position
  87. GRB 231118A: Skynet Optical Afterglow Discovery
  88. GRB 231118A: Swift detection of a burst
  89. GRB 231117A: ATCA detection of a radio counterpart
  90. GRB 231117A: GRBAlpha detection
  91. GRB 231117A: GIT optical follow-up
  92. GRB 231117A: Keck observations indicate presence of optical afterglow in z~0.3-0.5 galaxy
  93. GRB 231117A: REM optical and NIR early-time observations
  94. GRB 231117A: AKO Optical Upper Limit
  95. GRB 231117A: afterglow candidate detection from Kinder observations with Lulin observatory
  96. Swift GRB 231117A: Global MASTER-Net observations report
  97. GRB 231117A (short): Glowbug gamma-ray detection
  98. GRB 231117A: ATLAS non-detection of an optical counterpart
  99. Konus-Wind detection of GRB 231117A (short/hard)
  100. GRB 231115A: optical observations from INAF observatories

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