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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"

27250 results found.

  1. GRB 241016B: Swift/BAT-GUANO localization skymap of a short burst
  2. GRB 241017A: J-band upper limit from WINTER
  3. Fermi trigger No 750788395: Global MASTER-Net observations report
  4. GRB 241016B: SVOM/GRM observation
  5. GRB241016C: Fermi GBM Final Localization
  6. Fermi Gamma-ray Burst Monitor trigger 750792698/241016730 is not a GRB
  7. GRB 241017A : Detection of a weak and soft long duration GRB by SVOM/ECLAIRs
  8. Fermi GRB 241016B: Global MASTER-Net observations report
  9. GRB 241016B: Fermi GBM Final Localization
  10. Fermi GRB 241016A: Global MASTER-Net observations report
  11. GRB 241016A: Fermi GBM Final Real-time Localization
  12. IceCube Alert 241016.04: Global MASTER-Net observations report
  13. GRB 241010A: Swift-BAT refined analysis
  14. GRB 241013B: Fermi GBM Observation
  15. GRB 241013B: Swift/BAT-GUANO localization skymap of a burst
  16. GRB 241013A: Fermi GBM Observation
  17. GRB241013A: REM observations
  18. GRB 241013B: SVOM/GRM observation
  19. Fermi GRB 241013B: Global MASTER-Net observations report
  20. Integral GRB241013.04: Global MASTER-Net observations report
  21. GRB 241013B: Fermi GBM Final Real-time Localization
  22. GRB 241013A: Fermi GBM Final Real-time Localization
  23. Fermi Gamma-ray Burst Monitor GRB trigger 750372658/241011869 (GRB 241011A) is not a GRB
  24. GRB 241011A: Fermi GBM Final Real-time Localization
  25. GRB 241009A: GRANDMA optical upper limits
  26. GRB 241010A: JinShan optical observations and potential host galaxy
  27. GRB 241010A: Swift-XRT refined Analysis
  28. Fermi trigger No 750211959: Global MASTER-Net observations report
  29. Fermi Gamma-ray Burst Monitor trigger 750303285/241011066 is not a GRB
  30. Fermi Gamma-ray Burst Monitor trigger 750291012/241010924 is not a GRB
  31. Swift GRB 241010A: Global MASTER-Net observations report
  32. Fermi trigger No 750291012: Global MASTER-Net observations report
  33. Fermi GRB 241010B: Global MASTER-Net observations report
  34. GRB 241010B: Fermi GBM Final Real-time Localization
  35. GRB 241010A: LCO optical observations
  36. GRB 241010A: Swift detection of a burst with an optical counterpart
  37. GRB 241006A: Swift-BAT refined analysis
  38. GRB 241009A : Detection of a long duration GRB by SVOM/ECLAIRs
  39. GRB 241008A: Fermi GBM Observation
  40. GRB 241008A: Fermi-LAT detection
  41. GRB 241002A: NOT optical upper limits
  42. Fermi GRB 241008A: Global MASTER-Net observations report
  43. GRB 241008A: BALROG localization (Fermi Trigger 750117609 / GRB 241008917)
  44. GRB 241008A: Fermi GBM Final Real-time Localization
  45. GRB 241006A: GRANDMA optical upper limits
  46. EP trigger ID 01709065118: KAIT confirmation of the stellar flare
  47. GRB 241006A: Swift-XRT refined Analysis
  48. GRB 240821A: Host galaxy redshift from VLT/X-shooter
  49. GRB 241006A: Swift/UVOT Upper Limits
  50. GRB 241006A: SVOM/VT follow-up and optical upper limit
  51. IceCube Alert 241006.94: Global MASTER-Net observations report
  52. GRB 241006A: Swift detection of a burst
  53. Swift GRB241006.91: Global MASTER-Net observations report
  54. GRB 240930B: SVOM/C-GFT optical upper limit
  55. LIGO/Virgo/KAGRA S241005bo: Retraction of GW compact binary merger candidate
  56. Fermi trigger No 749721670: Global MASTER-Net observations report
  57. GRB 241004A: SVOM/GRM observation
  58. EP trigger ID 01709065118: the X-ray transient is likely a stellar flare event
  59. GRB 240930B / EP 240930a: SVOM/GRM observation
  60. GRB 241001A : ECLAIRs spectral analysis and XRF classification
  61. GRB 241002B: Fermi GBM Observation
  62. Fermi trigger No 749735279: Global MASTER-Net observations report
  63. Fermi trigger No 749630753: Global MASTER-Net observations report
  64. Fermi trigger No 749693019: Global MASTER-Net observations report
  65. GRB 241002C: SVOM/C-GFT optical upper limit
  66. GRB 241002A: Swift-BAT refined analysis
  67. GRB 241002B: Swift/BAT-GUANO localization skymap of a burst
  68. GRB 241002C: Swift-XRT observations confirm the source to be EI Eri
  69. Fermi-GBM Sub-Threshold Detection of GRB 241002D
  70. IPN triangulation of GRB 240930B / EP 240930a
  71. GRB 241001A : SVOM/VT optical detection
  72. GRB 241002B: GOTO24gpc/AT 2024xbg follow-up observations update
  73. GRB 241002D: SVOM/GRM observation
  74. GRB 241002B: ULL-ASTRO-MASTER LCOGT 0.4m + QHY600 detection of the GOTO optical counterpart candidate AT 2024xbg / GOTO24gpc
  75. GRB 240930B: CALET Gamma-Ray Burst Monitor detection
  76. GRB 241002C: X-ray afterglow candidate observed by SVOM/MXT
  77. GRB 241002C : MITSuME Akeno optical upper limits
  78. GRB241001A: REM optical/NIR upper limits
  79. GRB 241002A: Swift/UVOT Upper Limits
  80. EP240930a: Liverpool Telescope observations
  81. GRB 241002A: Swift-XRT refined Analysis
  82. GRB 241002A: LCOGT Optical Upper Limits
  83. GRB 241001A: GRANDMA and Kilonova-Catcher optical afterglow detection and upper limits
  84. GRB 241001A: Swift/UVOT Detection
  85. GRB 241002B: GOTO optical counterpart candidate
  86. EP trigger ID 01709064214: GOTO confirms detection as a flare star
  87. GRB 241002C : Detection of a long soft transient by SVOM/ECLAIRs
  88. GRB 240929A: Liverpool Telescope prompt followup observations
  89. Fermi GRB 241002B: Global MASTER-Net observations report
  90. EP trigger ID 01709064214: the X-ray transient is most likely a stellar flare event
  91. GRB 241002B: Fermi GBM Final Real-time Localization
  92. GRB241001A: optical afterglow candidate
  93. GRB 241001A: BOOTES-6/DPRT optical upper limit
  94. GRB 241002A: Swift detection of a burst
  95. GRB 240930B: Fermi GBM Observation
  96. EP240930a : KAIT optical upper limit
  97. GRB 241001A : Detection of a soft transient by ECLAIRs onboard SVOM
  98. GRB 240930B: Swift/BAT-GUANO localization skymap of a burst
  99. EP240930a: EP-FXT follow-up observation update
  100. EP240930a: GOTO optical upper limits

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