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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"

36400 results found.

  1. GRB 241013A: Fermi GBM Observation
  2. GRB 240916A: radio detection with the VLA
  3. GRB241013A: REM observations
  4. GRB 241009A: LCO optical upper limits
  5. GRB 241013B: SVOM/GRM observation
  6. Fermi GRB 241013B: Global MASTER-Net observations report
  7. GRB 241013B: Fermi GBM Final Real-time Localization
  8. GRB 241013A: a long GRB detected by INTEGRAL
  9. GRB 241013A: Fermi GBM Final Real-time Localization
  10. Fermi Gamma-ray Burst Monitor GRB trigger 750372658/241011869 (GRB 241011A) is not a GRB
  11. GRB 241011A: Fermi GBM Final Real-time Localization
  12. GRB 241009A: GRANDMA optical upper limits
  13. GRB 241009A: Swift-XRT afterglow detection
  14. GRB 241010A: JinShan optical observations and potential host galaxy
  15. GRB 241006A: ATCA Radio Upper Limits
  16. GRB 241010A: Swift-XRT refined Analysis
  17. Fermi Gamma-ray Burst Monitor trigger 750303285/241011066 is not a GRB
  18. Fermi Gamma-ray Burst Monitor trigger 750291012/241010924 is not a GRB
  19. Swift GRB 241010A: Global MASTER-Net observations report
  20. GRB 241010A: J-band observations with WINTER
  21. Fermi GRB 241010B: Global MASTER-Net observations report
  22. GRB 241010B: Fermi GBM Final Real-time Localization
  23. IceCube-241006A: Upper limits from a search for additional neutrino events in IceCube
  24. GRB 241010A: Enhanced Swift-XRT position
  25. GRB 241010A: LCO optical observations
  26. GRB 241010A: Swift detection of a burst with an optical counterpart
  27. GRB 241006A: Swift-BAT refined analysis
  28. GRB 241009A: Swift ToO observations
  29. GRB 241009A : Detection of a long duration GRB by SVOM/ECLAIRs
  30. GRB 241008A: Fermi GBM Observation
  31. GRB 241008A: Fermi-LAT detection
  32. GRB 241002B: Swift-XRT afterglow detection
  33. GRB 241002A: NOT optical upper limits
  34. Fermi GRB 241008A: Global MASTER-Net observations report
  35. GRB 241008A: BALROG localization (Fermi Trigger 750117609 / GRB 241008917)
  36. GRB 241008A: Fermi GBM Final Real-time Localization
  37. GRB 241006A: GRANDMA optical upper limits
  38. EP240930a / GRB 240930B: CrAO ZTSH optical upper limit
  39. GRB 241002B: PRIME near-infrared detection in 3rd epoch
  40. GRB 240910A: LBT optical observations
  41. EP trigger ID 01709065118: KAIT confirmation of the stellar flare
  42. GRB 241006A: Swift-XRT refined Analysis
  43. GRB 240821A: Host galaxy redshift from VLT/X-shooter
  44. GRB 241006A: PRIME near-infrared upper limits
  45. GRB 241006A: Swift/UVOT Upper Limits
  46. GRB 241006A: SVOM/VT follow-up and optical upper limit
  47. GRB 241001A: Swift-XRT afterglow detection
  48. GRB 241006A: Enhanced Swift-XRT position
  49. GRB 241006A: Swift detection of a burst
  50. GRB 240930B: SVOM/C-GFT optical upper limit
  51. GRB 241004A: SVOM/GRM observation
  52. GRB 240930B / EP 240930a: SVOM/GRM observation
  53. GRB 241001A : ECLAIRs spectral analysis and XRF classification
  54. GRB 241002B: PRIME near-infrared detection in 2nd epoch
  55. GRB 241002B: Fermi GBM Observation
  56. GRB 241002B: Swift-XRT observations
  57. GRB 241002C: SVOM/C-GFT optical upper limit
  58. GRB 241002A: Swift-BAT refined analysis
  59. GRB 241002B: Swift/BAT-GUANO localization skymap of a burst
  60. GRB 241002B: Swift ToO observations
  61. GRB 241002C: Swift-XRT observations confirm the source to be EI Eri
  62. Konus-Wind detection of GRB 240926A
  63. GRB 241002B: PRIME near-infrared detection
  64. GRB 241002C: Swift ToO observations
  65. Fermi-GBM Sub-Threshold Detection of GRB 241002D
  66. IPN triangulation of GRB 240930B / EP 240930a
  67. GRB 241001A : SVOM/VT optical detection
  68. GRB 241002B: GOTO24gpc/AT 2024xbg follow-up observations update
  69. GRB 241002D: SVOM/GRM observation
  70. GRB 241002B: ULL-ASTRO-MASTER LCOGT 0.4m + QHY600 detection of the GOTO optical counterpart candidate AT 2024xbg / GOTO24gpc
  71. GRB 240930B: CALET Gamma-Ray Burst Monitor detection
  72. GRB 241002C: X-ray afterglow candidate observed by SVOM/MXT
  73. GRB 240929A: SAO RAS, Mondy, and CrAO optical observations
  74. GRB 241002C : MITSuME Akeno optical upper limits
  75. LIGO/Virgo/KAGRA S240925n: Updated Sky localization
  76. NuEm-240926A: Upper limits from a search for coincident neutrino events in IceCube
  77. GRB241001A: REM optical/NIR upper limits
  78. GRB 241002A: Swift/UVOT Upper Limits
  79. GRB 241002A: Swift-XRT refined Analysis
  80. GRB 241002A: LCOGT Optical Upper Limits
  81. GRB 241001A: GRANDMA and Kilonova-Catcher optical afterglow detection and upper limits
  82. GRB 241001A: Swift/UVOT Detection
  83. GRB 241001A: VLT/X-shooter redshift
  84. GRB 241002B: GOTO optical counterpart candidate
  85. GRB 241002C : Detection of a long soft transient by SVOM/ECLAIRs
  86. GRB 241001A: correction to GCN 37667
  87. GRB 240929A: Liverpool Telescope prompt followup observations
  88. Fermi GRB 241002B: Global MASTER-Net observations report
  89. GRB 241001A: Swift-XRT observations
  90. GRB 241002B: Fermi GBM Final Real-time Localization
  91. GRB241001A: optical afterglow candidate
  92. GRB 241002A: 1.5m OSN optical upper limit
  93. GRB 241002A: Enhanced Swift-XRT position
  94. GRB 241001A: BOOTES-6/DPRT optical upper limit
  95. GRB 241002A: Swift detection of a burst
  96. GRB 240930B: Fermi GBM Observation
  97. GRB 241001A: Swift ToO observations
  98. GRB 240930B: GRBAlpha detection
  99. GRB 240929A: GRBAlpha detection
  100. EP240930a : KAIT optical upper limit

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