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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"

19605 results found.

  1. GRB 231215C: MASTER OT detection
  2. Swift GRB231215.41: Global MASTER-Net observations report
  3. GRB 231215A: Swift-XRT observations
  4. GRB 231215A: Swift detection of a burst
  5. GRB 231214A: Fermi-LAT detection
  6. GRB 231214A: Enhanced Swift-XRT position
  7. GRB 231214B: Swift/BAT-GUANO detection of a burst
  8. GRB231214A: BOOTES-6/DPRT optical upper limit
  9. Swift GRB231214.85: Global MASTER-Net observations report
  10. GRB 231214A: Swift detection of a burst
  11. GRB 231210B: REM optical/NIR upper limits
  12. LIGO/Virgo/KAGRA S231206cc: Upper limits from Swift/BAT-GUANO
  13. LIGO/Virgo/KAGRA S231206ca: Upper limits from Swift/BAT-GUANO
  14. GRB 231210B: MeerLICHT afterglow observations
  15. GRB 231210B: Swift-BAT refined analysis
  16. GRB 231210B: Swift-XRT refined Analysis
  17. GRB 231210B: Enhanced Swift-XRT position
  18. GRB 231210B: VLT/X-shooter redshift
  19. GRB 231210B: detection of the optical counterpart with the LCOGT 40cm telescope at Sutherland Observatory
  20. GRB 231210B: Swift detection of a burst with optical counterpart
  21. Swift GRB231210.90: Global MASTER-Net OT detection
  22. Swift GRB231210.90: Global MASTER-Net observations report
  23. IPN triangulation of GRB 231129C
  24. GRB231205B: Swift/UVOT Upper Limits
  25. GRB 231205B: Swift-BAT refined analysis
  26. GRB 231205B: 1.3m DFOT Optical upper limit
  27. GRB 231205B: AGILE detection
  28. GRB 231205B: Ondrejov D50 optical upper limit
  29. GRB 231205B: Swift-XRT refined Analysis
  30. GRB 231205B: REM optical/NIR upper limits
  31. GRB 231129C: ASIM MXGS observation and localization
  32. GRB 231205B: r'-band observations from MISTRAL at Observatoire de Haute-Provence
  33. GRB 231205B : MITSuME Akeno optical upper limits
  34. GRB 231205B: Zadko observatory - Gingin optical observations
  35. GRB 231205B: Gaoyazi/GOT optical upper limit
  36. GRB 231205B: Nanshan/HMT optical upper limit
  37. GRB 231205B: GECAM-B detection of a long burst
  38. GRB 231205B: LCOGT Optical Upper Limits
  39. GRB 231205B: Enhanced Swift-XRT position
  40. Swift GRB231205.70: Global MASTER-Net observations report
  41. GRB 231205B: AKO Optical Upper Limit
  42. GRB 231205B: Swift detection of a burst
  43. LIGO/Virgo/KAGRA S231129ac: Upper limits from Swift/BAT-GUANO
  44. GRB 231203A: Fermi GBM Observation
  45. GRB 231203A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  46. Konus-Wind detection of GRB 231129C
  47. GRB 231129C: Swift-XRT afterglow detection
  48. GRB 231129C: PROMPT optical upper limits for the MAXI/GSC X-ray counterpart and the MASTER afterglow candidate
  49. GRB 231129A: VZLUSAT-2 detection
  50. GRB 231129B: Swift-XRT observations
  51. GRB 231129C: AGILE detection
  52. GRB 231129A : MITSuME Akeno optical upper limits
  53. GRB 231129C: Swift/BAT-GUANO localization of a burst outside the coded FOV
  54. GRB 231129A: Swift-BAT refined analysis
  55. GRB 231129C: MASTER OT detection
  56. GRB 231129A: BOOTES-5/JGT optical upper limit
  57. GRB 231129A: JinShan optical upper limit
  58. GRB 231129C: Swift-XRT observations
  59. GRB 231129A: Swift/UVOT Upper Limits
  60. GRB 231129A: optical upper limit in Mondy observatory
  61. GRB 231129C: Tiled Swift observations
  62. GRB 231129A: Enhanced Swift-XRT position
  63. GRB 231129A: Swift-XRT refined Analysis
  64. GRB 231129B: Tiled Swift observations
  65. GRB 231129A: GECAM-C detection of a long burst
  66. GRB 231129A: INTEGRAL detection of a long GRB
  67. GRB 231129A: Swift detection of a burst
  68. GRB 231123C: Fermi GBM Observation
  69. GRB 231123B: Fermi GBM Observation
  70. GRB 231123B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  71. GRB 231111A: Optical follow-up observations at Terskol, AbAO, Maidanak, Mondy, Assy
  72. GRB 231123C: Insight-HXMT/HE detection
  73. GRB 231123C (short): Glowbug gamma-ray detection
  74. GRB230506B: VIRT optical upper limit
  75. GRB 231123C: Swift/BAT-GUANO detection of a short burst likely outside the coded FOV
  76. GRB 231115A: XMM-Newton observation
  77. GRB 231118A: REM optical afterglow detection
  78. GRB 231122B: AstroSat CZTI detection
  79. GRB 231122B: CALET Gamma-Ray Burst Monitor detection
  80. GRB 231122B: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  81. GRB 231118A: ATCA detection of radio counterpart
  82. GRB 231117A: Swift/UVOT late time observations
  83. GRB 231117A: Swift-BAT refined analysis
  84. GRB 231118A: GRBAlpha detection
  85. LIGO/Virgo/KAGRA S231118d: Upper limits from Swift/BAT-GUANO
  86. LIGO/Virgo/KAGRA S231118an: Upper limits from Swift/BAT-GUANO
  87. LIGO/Virgo/KAGRA S231114n: Upper limits from Swift/BAT-GUANO
  88. LIGO/Virgo/KAGRA S231113bb: Upper limits from Swift/BAT-GUANO
  89. GRB 231118A: VZLUSAT-2 detection
  90. GRB 231118A: Swift-BAT refined analysis
  91. GRB 231117A: CALET Gamma-Ray Burst Monitor detection
  92. 231118A: Swift-UVOT Detection
  93. GRB231117A: Swift-UVOT detection
  94. GRB 231118A: Fermi GBM observation
  95. GRB 231117A: Swift-XRT refined Analysis
  96. GRB 231118A: Swift-XRT refined Analysis
  97. GRB 231118A: MeerLICHT afterglow detection
  98. GRB 231118A: VLT/X-shooter redshift
  99. GRB 231117A: MAAO 0.7-m telescope optical upper limit
  100. GRB 231117A: GECAM-C detection

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