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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"

45790 results found.

  1. Fermi trigger No 737788024: Global MASTER-Net observations report
  2. EP240518a: possibly identified with a flare star by EP-FXT
  3. GRB 240519A: BALROG localization (Fermi Trigger 737788024 / GRB 240519213)
  4. EP240518a: EP-WXT detection of a new X-ray transient
  5. LIGO/Virgo/KAGRA S240514c: Updated Sky localization
  6. GRB 240516A: Swift-BAT refined analysis
  7. Fermi GRB 240517A: Global MASTER-Net observations report
  8. GRB 240516A ATCA radio observations
  9. IPN triangulation of GRB 240514B (short)
  10. GRB 240513A: Swift ToO observations
  11. GRB 240517A: Fermi GBM Final Real-time Localization
  12. Konus-Wind detection of GRB 240513A
  13. GRB 240516A: AstroSat CZTI detection
  14. GRB 240516A: Swift-XRT refined Analysis
  15. GRB 240514E: A possible candidate BD-21 1074
  16. Fermi trigger No 737559855: Global MASTER-Net observations report
  17. GRB 240516A: Fermi GBM Observation
  18. GRB 240511A: Observations from GTC/OSIRIS+
  19. GRB 240502C: Zeiss-1000 at Koshka observations of GOTO24bao optical counterpart candidate
  20. GRB 240516A: GOTO optical upper limit
  21. LIGO/Virgo/KAGRA S240422ed: GRID non-detection and upper limits
  22. Fermi trigger No 737523389: Global MASTER-Net observations report
  23. GRB 240516A: Swift detection of a burst
  24. Swift GRB240516.15: Global MASTER-Net observations report
  25. GRB 240514B: AT2024ixa/GOTO24bph is not consistent with the Fermi localisation
  26. Fermi trigger No 737476171: Global MASTER-Net observations report
  27. GRB 240511A: radio detection of afterglow candidate
  28. GRB 240514B: GOTO candidate optical counterpart
  29. MAXI GRB240514.78: Global MASTER-Net observations report
  30. Fermi Gamma-ray Burst Monitor list of triggers that are not a GRB
  31. GRB 240514E: MAXI/GSC detection of a probable afterglow
  32. GRB 240514B: GRBAlpha detection
  33. LIGO/Virgo/KAGRA S240514x: Updated Sky localization
  34. LIGO/Virgo/KAGRA S240515m: Identification of a GW compact binary merger candidate
  35. GRB 240514B: Fermi GBM Detection
  36. LIGO/Virgo/KAGRA S240422ed: Las Cumbres Observatory Follow-up Observations of the Localization Region
  37. GRB 240513A: Fermi GBM observation
  38. GRB 240513A: Swift-XRT observations
  39. LIGO/Virgo/KAGRA S240513ei: Updated Sky localization
  40. LIGO/Virgo/KAGRA S240514x: Identification of a GW compact binary merger candidate
  41. GRB 240514D: AstroSat CZTI detection
  42. GRB 240514C: Fermi GBM Final Real-time Localization
  43. LIGO/Virgo/KAGRA S240514c: Identification of a GW compact binary merger candidate
  44. Fermi GRB 240514B: Global MASTER-Net observations report
  45. transient: Xinglong Nearby Galaxy Supernova Survey detection of AT2024iss
  46. GRB 240514B: Fermi GBM Final Real-time Localization
  47. LIGO/Virgo/KAGRA S240507p: Upper limits from Swift/BAT-GUANO
  48. LIGO/Virgo/KAGRA S240505av: Upper limits from Swift/BAT-GUANO
  49. LIGO/Virgo/KAGRA S240505av: Upper limits from Swift/BAT-GUANO
  50. GRB 240514A: Fermi GBM Final Real-time Localization
  51. GRB 240513A: Tiled Swift observations
  52. LAT GRB240513.31: Global MASTER-Net observations report
  53. GRB 240513A: Fermi-LAT detection
  54. LIGO/Virgo/KAGRA S240513ei: Identification of a GW compact binary merger candidate
  55. GRB 240511A: Fermi GBM Observation
  56. GRB 240511A: Swift-BAT refined analysis
  57. Fermi GRB 240513B: Global MASTER-Net observations report
  58. Fermi trigger No 737277727: Global MASTER-Net observations report
  59. GRB 240513B: Fermi GBM Final Real-time Localization
  60. GRB 240513A: AstroSat CZTI detection
  61. LIGO/Virgo/KAGRA S240513cx: Coverage and upper limits from MAXI/GSC observations
  62. Fermi trigger No 737258655: Global MASTER-Net observations report
  63. GRB 240511A: J-band observations with WINTER
  64. Fermi trigger No 737247400: Global MASTER-Net observations report
  65. Fermi trigger No 737244199: Global MASTER-Net observations report
  66. Fermi trigger No 737218721: Global MASTER-Net observations report
  67. Fermi trigger No 737196587: Global MASTER-Net observations report
  68. Fermi trigger No 737168073: Global MASTER-Net observations report
  69. GRB 240511A: Enhanced Swift-XRT position
  70. GRB 240511A : MITSuME Akeno optical upper limits
  71. LIGO/Virgo/KAGRA S240512r: Updated Sky localization and EM Bright Classification
  72. GRB 240511A: Swift-XRT refined Analysis
  73. GRB 240511A: optical afterglow detection from the NOT
  74. Fermi Gamma-ray Burst Monitor trigger 737102480/240511279 is not a GRB
  75. Fermi Gamma-ray Burst Monitor trigger 737111207/240511380 is not a GRB
  76. Fermi GBM trigger 737105243/240511311 is not a GRB
  77. Fermi trigger No 737173236: Global MASTER-Net observations report
  78. LIGO/Virgo/KAGRA S240512r: Identification of a GW compact binary merger candidate
  79. Fermi GRB 240511A: Global MASTER-Net observations report
  80. Swift GRB 240511A: Global MASTER-Net observations report
  81. Fermi trigger No 737105243: Global MASTER-Net observations report
  82. Fermi Gamma-ray Burst Monitor trigger 737133200/240511634 is not a GRB
  83. Fermi trigger No 737152719: Global MASTER-Net observations report
  84. GRB 240511A: Prompt enhanced Swift-XRT position
  85. GRB 240511A: Swift detection of a burst
  86. LIGO/Virgo/KAGRA S240511i: Updated Sky localization
  87. GRB 240511A: Fermi GBM Final Real-time Localization
  88. Fermi trigger No 737102480: Global MASTER-Net observations report
  89. Fermi trigger No 737111207: Global MASTER-Net observations report
  90. LIGO/Virgo/KAGRA S240511i: Identification of a GW compact binary merger candidate
  91. LIGO/Virgo/KAGRA S240422ed: GMOS-S photometry of J-GEM24a
  92. LIGO/Virgo/KAGRA S240422ed: P200 observations of AT2024hit
  93. LIGO/Virgo/KAGRA S240422ed: Candidates from the latest GW-MMADS DECam Observations
  94. Fermi trigger No 736967879: Global MASTER-Net observations report
  95. EP240506a: Xinglong optical upper limit
  96. Fermi Gamma-ray Burst Monitor trigger 230925241/717313591 is not a GRB
  97. EP240506a: CrAO ZTSH optical upper limit
  98. GRB 240504A: Fermi GBM Observation
  99. Fermi Gamma-ray Burst Monitor trigger 736837160/240508208 is not a GRB
  100. EP240506a: Archival radio searching

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