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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"

36280 results found.

  1. GRB241016C: Fermi GBM Final Localization
  2. Fermi Gamma-ray Burst Monitor trigger 750792698/241016730 is not a GRB
  3. GRB 241017A: Swift ToO observations
  4. GRB 241017A : Detection of a weak and soft long duration GRB by SVOM/ECLAIRs
  5. Fermi GRB 241016B: Global MASTER-Net observations report
  6. GRB 241016B: Fermi GBM Final Localization
  7. Fermi GRB 241016A: Global MASTER-Net observations report
  8. GRB 241016A: Fermi GBM Final Real-time Localization
  9. GRB 241010A: Swift-BAT refined analysis
  10. GRB 241013B: Fermi GBM Observation
  11. GRB 241013B: Swift/BAT-GUANO localization skymap of a burst
  12. GRB 241013A: Fermi GBM Observation
  13. GRB 240916A: radio detection with the VLA
  14. GRB241013A: REM observations
  15. GRB 241009A: LCO optical upper limits
  16. GRB 241013B: SVOM/GRM observation
  17. Fermi GRB 241013B: Global MASTER-Net observations report
  18. GRB 241013B: Fermi GBM Final Real-time Localization
  19. GRB 241013A: a long GRB detected by INTEGRAL
  20. GRB 241013A: Fermi GBM Final Real-time Localization
  21. Fermi Gamma-ray Burst Monitor GRB trigger 750372658/241011869 (GRB 241011A) is not a GRB
  22. GRB 241011A: Fermi GBM Final Real-time Localization
  23. GRB 241009A: GRANDMA optical upper limits
  24. GRB 241009A: Swift-XRT afterglow detection
  25. GRB 241010A: JinShan optical observations and potential host galaxy
  26. GRB 241006A: ATCA Radio Upper Limits
  27. GRB 241010A: Swift-XRT refined Analysis
  28. Fermi Gamma-ray Burst Monitor trigger 750303285/241011066 is not a GRB
  29. Fermi Gamma-ray Burst Monitor trigger 750291012/241010924 is not a GRB
  30. Swift GRB 241010A: Global MASTER-Net observations report
  31. GRB 241010A: J-band observations with WINTER
  32. Fermi GRB 241010B: Global MASTER-Net observations report
  33. GRB 241010B: Fermi GBM Final Real-time Localization
  34. GRB 241010A: Enhanced Swift-XRT position
  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: Swift ToO observations
  39. GRB 241009A : Detection of a long duration GRB by SVOM/ECLAIRs
  40. GRB 241008A: Fermi GBM Observation
  41. GRB 241008A: Fermi-LAT detection
  42. GRB 241002B: Swift-XRT afterglow detection
  43. GRB 241002A: NOT optical upper limits
  44. Fermi GRB 241008A: Global MASTER-Net observations report
  45. GRB 241008A: BALROG localization (Fermi Trigger 750117609 / GRB 241008917)
  46. GRB 241008A: Fermi GBM Final Real-time Localization
  47. GRB 241006A: GRANDMA optical upper limits
  48. EP240930a / GRB 240930B: CrAO ZTSH optical upper limit
  49. GRB 241002B: PRIME near-infrared detection in 3rd epoch
  50. GRB 240910A: LBT optical observations
  51. EP trigger ID 01709065118: KAIT confirmation of the stellar flare
  52. GRB 241006A: Swift-XRT refined Analysis
  53. GRB 240821A: Host galaxy redshift from VLT/X-shooter
  54. GRB 241006A: PRIME near-infrared upper limits
  55. GRB 241006A: Swift/UVOT Upper Limits
  56. GRB 241006A: SVOM/VT follow-up and optical upper limit
  57. GRB 241001A: Swift-XRT afterglow detection
  58. GRB 241006A: Enhanced Swift-XRT position
  59. GRB 241006A: Swift detection of a burst
  60. GRB 240930B: SVOM/C-GFT optical upper limit
  61. GRB 241004A: SVOM/GRM observation
  62. GRB 240930B / EP 240930a: SVOM/GRM observation
  63. GRB 241001A : ECLAIRs spectral analysis and XRF classification
  64. GRB 241002B: PRIME near-infrared detection in 2nd epoch
  65. GRB 241002B: Fermi GBM Observation
  66. GRB 241002B: Swift-XRT observations
  67. GRB 241002C: SVOM/C-GFT optical upper limit
  68. GRB 241002A: Swift-BAT refined analysis
  69. GRB 241002B: Swift/BAT-GUANO localization skymap of a burst
  70. GRB 241002B: Swift ToO observations
  71. GRB 241002C: Swift-XRT observations confirm the source to be EI Eri
  72. Konus-Wind detection of GRB 240926A
  73. GRB 241002B: PRIME near-infrared detection
  74. GRB 241002C: Swift ToO observations
  75. Fermi-GBM Sub-Threshold Detection of GRB 241002D
  76. IPN triangulation of GRB 240930B / EP 240930a
  77. GRB 241001A : SVOM/VT optical detection
  78. GRB 241002B: GOTO24gpc/AT 2024xbg follow-up observations update
  79. GRB 241002D: SVOM/GRM observation
  80. GRB 241002B: ULL-ASTRO-MASTER LCOGT 0.4m + QHY600 detection of the GOTO optical counterpart candidate AT 2024xbg / GOTO24gpc
  81. GRB 240930B: CALET Gamma-Ray Burst Monitor detection
  82. GRB 241002C: X-ray afterglow candidate observed by SVOM/MXT
  83. GRB 240929A: SAO RAS, Mondy, and CrAO optical observations
  84. GRB 241002C : MITSuME Akeno optical upper limits
  85. GRB241001A: REM optical/NIR upper limits
  86. GRB 241002A: Swift/UVOT Upper Limits
  87. GRB 241002A: Swift-XRT refined Analysis
  88. GRB 241002A: LCOGT Optical Upper Limits
  89. GRB 241001A: GRANDMA and Kilonova-Catcher optical afterglow detection and upper limits
  90. GRB 241001A: Swift/UVOT Detection
  91. GRB 241001A: VLT/X-shooter redshift
  92. GRB 241002B: GOTO optical counterpart candidate
  93. GRB 241002C : Detection of a long soft transient by SVOM/ECLAIRs
  94. GRB 241001A: correction to GCN 37667
  95. GRB 240929A: Liverpool Telescope prompt followup observations
  96. Fermi GRB 241002B: Global MASTER-Net observations report
  97. GRB 241001A: Swift-XRT observations
  98. GRB 241002B: Fermi GBM Final Real-time Localization
  99. GRB241001A: optical afterglow candidate
  100. GRB 241002A: 1.5m OSN optical upper limit

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