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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"

45832 results found.

  1. GRB 240101C: Fermi GBM Final Localization
  2. Swift GRB240101.85: Global MASTER-Net observations report
  3. GRB 240101B: Swift detection of a burst
  4. GRB 240101A: Swift detection of a burst
  5. Fermi trigger No 725806648: Global MASTER-Net observations report
  6. LIGO/Virgo/KAGRA S231231ag: Updated Sky localization and Source Classification
  7. LIGO/Virgo/KAGRA S231231ag: Identification of a GW compact binary merger candidate
  8. GRB231230A: Fermi GBM Observation
  9. GRB 231230A: Swift-XRT refined Analysis
  10. GRB 231230A: GOTO optical upper limits
  11. GRB 231230A: Enhanced Swift-XRT position
  12. GRB 231230A: Swift/UVOT Upper Limits
  13. GRB 231230A: NOT optical upper limits
  14. Fermi trigger No 725592555: Global MASTER-Net observations report
  15. GRB 231230A: Prompt enhanced Swift-XRT position
  16. GRB 231230A: Swift detection of a burst
  17. Swift GRB231230.06: Global MASTER-Net observations report
  18. GRB 231230A: Fermi GBM Final Real-time Localization
  19. GRB 231210B: BOOTES-7 optical upper limit
  20. Swift Triggers 1205103, 1205104, 1205107 and 1205110 are not astrophysical events
  21. LIGO/Virgo/KAGRA S231224e: Upper limits from Swift/BAT-GUANO
  22. IPN triangulation of GRB 231224A (short)
  23. LIGO/Virgo/KAGRA S231226av: Updated Sky localization
  24. LIGO/Virgo/KAGRA S231226av: Identification of a GW compact binary merger candidate
  25. Fermi trigger No 725143760: Global MASTER-Net observations report
  26. GRB 231224A: Fermi GBM Final Real-time Localization
  27. GRB 231222B: GRBAlpha detection
  28. LIGO/Virgo/KAGRA S231224e: Updated Sky localization and Source Classification
  29. LIGO/Virgo/KAGRA S231224e: Identification of a GW compact binary merger candidate
  30. LIGO/Virgo/KAGRA S231223j: Updated Sky localization
  31. GRB 231222B: Swift-XRT afterglow detection
  32. LIGO/Virgo/KAGRA S231223j: Identification of a GW compact binary merger candidate
  33. Fermi trigger No 724921799: Global MASTER-Net observations report
  34. GRB 231222B: Fermi GBM Detection
  35. LAT GRB231222.31: Global MASTER-Net observations report
  36. GRB 231222B: Fermi-LAT detection
  37. GRB 231222A: Tiled Swift observations
  38. IceCube-231211A: GRANDMA observations of PKS2047+098
  39. GRID detection of GRB 231215A
  40. GRB 231222A: Fermi GBM Final Real-time Localization
  41. GRB 231220A: Swift-XRT follow-up observations
  42. GRB 231220A: Swift ToO observations
  43. GRB 231220A: Swift/BAT-GUANO arcminute localization of a long burst
  44. Fermi trigger No 724781422: Global MASTER-Net observations report
  45. GRB 231220A: Fermi GBM Final Real-time Localization
  46. GRB 231210B: new optical transient detected with the Greenhill Observatory University of Tasmania within the BAT-Swift enhanced position
  47. Fermi trigger No 724698747: Global MASTER-Net observations report
  48. GRB 231219A: Fermi GBM Final Real-time Localization
  49. GRID detection of GRB 231205B
  50. GRID detection of GRB 231205A
  51. GRB 231216A: GAD Observatory, La Spezia, Italy upper limit
  52. GRB 231214B: Fermi GBM observation
  53. GRB 231216A: optical upper limits from the INAF Asiago Observatory
  54. GRB 231216A: 10.4 m GTC optical upper limit
  55. GRB 231215A: AMI-LA radio detection
  56. GRB 231216A: Nanshan/HMT optical upper limit
  57. GRB 231216A: LCOGT Optical Upper Limits
  58. GRB 231216A: Osservatorio Astronomico Nastro Verde upper limit
  59. GRB 231216A: Swift-XRT refined analysis correction
  60. GRB 231215A: Osservatorio Astronomico Nastro Verde upper limit
  61. GRB 231216A: Swift-XRT refined Analysis
  62. GRB 231216A: AST3-3 YaoAn Optical Upper Limit
  63. GRB 231216A: REM NIR upper limits
  64. GRB 231216A: Swift/UVOT Upper Limits
  65. GRB 231216A: Swift-BAT refined analysis
  66. GRB 231215A: Swift-BAT refined analysis
  67. GRB 231214A: Swift-BAT refined analysis
  68. GRB 231216A: R-band observations from T120 at Observatoire de Haute-Provence
  69. GRB 231216A: GIT optical upper limit
  70. GRB 231216A: NOT optical upper limits
  71. GRB 231216A: BOOTES-2/TELMA optical upper limit
  72. GRB 231215A: GRBAlpha detection
  73. Swift GRB231216.77: Global MASTER-Net observations report
  74. GRB 231216A: Swift detection of a burst
  75. Konus-Wind detection of GRB 231215A
  76. GRB 231215A: optical afterglow detection from the INAF Asiago Observatory
  77. GRB 231215A: NOT optical observations
  78. GRB 231214A: Swift/UVOT Upper Limits
  79. GRB 231215A: Redshift from OSIRIS+ / GTC
  80. GRB 231205B: VZLUSAT-2 detection
  81. GRB 231204A: VZLUSAT-2 detection
  82. GRB 231215A: GAD Observatory, La Spezia, Italy upper limit;
  83. GRB 231215A: Fermi GBM observation
  84. GRB 231215A: CALET Gamma-Ray Burst Monitor detection
  85. GRB 231215A : OHP/T193 optical afterglow detection
  86. GRB 231215A: Swift/UVOT Detection
  87. LIGO/Virgo/KAGRA S231215i: 3 counterpart neutrino candidate events from an IceCube neutrino search
  88. GRB 231215A: Swift-XRT refined Analysis
  89. GRB 231215A: BOOTES-4/MET optical detection
  90. GRB 231215A: AKO Optical Upper Limit
  91. GRB 231215A: AGILE detection
  92. GRB 231214A: Fermi GBM observation
  93. Konus-Wind detection of GRB 231210B
  94. ATCA observations of GRB 231210B
  95. GRB 231215A: Enhanced Swift-XRT position
  96. Fermi trigger No 724326442: Global MASTER-Net observations report
  97. GRB 231214A: REM optical/NIR upper limits
  98. GRB 231215A: GROWTH-India optical follow-up
  99. GRB 231215A : Nanshan/HMT optical observations
  100. GRB 231215A: AstroSat CZTI detection

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