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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"

14856 results found.

  1. EP241025a (GRB 241025A): EP on-board trigger and autonomous follow-up observation
  2. GRB 241025A: SVOM/GRM observation
  3. GRB 241025A: Fermi GBM Final Real-time Localization
  4. GRB 241025A: Swift detection of a burst with an optical counterpart
  5. GRB 241001A: ATCA radio observations
  6. GRB 241024B: Fermi GBM Final Localization
  7. EP241021a: No Detection in Fermi-GBM Observation
  8. GRB 241010A: VIRT Optical Upper Limit
  9. GRB 241024A: Fermi GBM Final Localisation
  10. EP241021a: VLT/FORS2 redshift z = 0.75
  11. EP241021a: EP-FXT follow-up observation update
  12. EP241021a: Optical counterpart observations with the Liverpool Telescope
  13. EP241021a: 1.3m DFOT Optical observations
  14. EP241021a: NOT likely optical counterpart
  15. GRB241017A: 1.3m DFOT optical upper limit
  16. GRB 241018A: 1.3m DFOT Optical upper limit
  17. GRB 241018A: EP-FXT afterglow detection
  18. EP241021a: EP detection of a fast X-ray transient
  19. Konus-Wind detection of GRB 241018A
  20. GRB 241018A: SVOM/GRM observation
  21. GRB 241018A: BOOTES-4/MET optical upper limit
  22. GRB 241018A: Mondy optical upper limit
  23. GRB 241006A: VIRT Optical Upper Limit
  24. GRB 240727A: VIRT Optical Upper Limit
  25. GRB 241018A: X-ray afterglow candidate observed by MXT
  26. GRB 241018A: Detection of a bright long GRB by SVOM
  27. GRB 241001A: EP-FXT afterglow detection
  28. GRB 241016B: SVOM/GRM observation
  29. GRB241016C: Fermi GBM Final Localization
  30. GRB 241017A : Detection of a weak and soft long duration GRB by SVOM/ECLAIRs
  31. GRB 241016B: Fermi GBM Final Localization
  32. GRB 241016A: Fermi GBM Final Real-time Localization
  33. IceCube alert 139977_2910365 retraction
  34. GRB 240916A: radio detection with the VLA
  35. GRB 241013B: SVOM/GRM observation
  36. GRB 241013B: Fermi GBM Final Real-time Localization
  37. GRB 241013A: Fermi GBM Final Real-time Localization
  38. GRB 241011A: Fermi GBM Final Real-time Localization
  39. GRB 241009A: Swift-XRT afterglow detection
  40. GRB 241010B: Fermi GBM Final Real-time Localization
  41. GRB 241010A: Swift detection of a burst with an optical counterpart
  42. GRB 241009A : Detection of a long duration GRB by SVOM/ECLAIRs
  43. GRB 241008A: Fermi-LAT detection
  44. GRB 241002B: Swift-XRT afterglow detection
  45. GRB 241008A: Fermi GBM Final Real-time Localization
  46. IceCube-241006A: No candidates from the Zwicky Transient Facility
  47. GRB 241002B: PRIME near-infrared detection in 3rd epoch
  48. GRB 240821A: Host galaxy redshift from VLT/X-shooter
  49. GRB 241006A: PRIME near-infrared upper limits
  50. GRB 241001A: Swift-XRT afterglow detection
  51. IceCube-241006A - IceCube observation of a high-energy neutrino candidate track-like event
  52. GRB 241006A: Swift detection of a burst
  53. LIGO/Virgo/KAGRA S241005bo: Retraction of GW compact binary merger candidate
  54. GRB 241004A: SVOM/GRM observation
  55. GRB 240930B / EP 240930a: SVOM/GRM observation
  56. GRB 241002B: PRIME near-infrared detection in 2nd epoch
  57. Konus-Wind detection of GRB 240926A
  58. GRB 241002B: PRIME near-infrared detection
  59. Fermi-GBM Sub-Threshold Detection of GRB 241002D
  60. IPN triangulation of GRB 240930B / EP 240930a
  61. GRB 241001A : SVOM/VT optical detection
  62. GRB 241002B: GOTO24gpc/AT 2024xbg follow-up observations update
  63. GRB 241002D: SVOM/GRM observation
  64. GRB 241002B: ULL-ASTRO-MASTER LCOGT 0.4m + QHY600 detection of the GOTO optical counterpart candidate AT 2024xbg / GOTO24gpc
  65. GRB 240930B: CALET Gamma-Ray Burst Monitor detection
  66. GRB 241001A: GRANDMA and Kilonova-Catcher optical afterglow detection and upper limits
  67. GRB 241001A: Swift/UVOT Detection
  68. GRB 241001A: VLT/X-shooter redshift
  69. EP trigger ID 01709064214: GOTO confirms detection as a flare star
  70. GRB 241002C : Detection of a long soft transient by SVOM/ECLAIRs
  71. EP trigger ID 01709064214: the X-ray transient is most likely a stellar flare event
  72. GRB 241002B: Fermi GBM Final Real-time Localization
  73. GRB241001A: optical afterglow candidate
  74. GRB 241002A: 1.5m OSN optical upper limit
  75. GRB 241001A: BOOTES-6/DPRT optical upper limit
  76. GRB 241002A: Swift detection of a burst
  77. GRB 240930B: GRBAlpha detection
  78. GRB 240929A: GRBAlpha detection
  79. GRB 241001A : Detection of a soft transient by ECLAIRs onboard SVOM
  80. EP240930a: EP-FXT follow-up observation update
  81. GRB 240929A: SVOM/GRM observation
  82. EP240930a: EP-WXT detection of a fast X-ray transient
  83. SVOM/GRM detection of a burst from SGR Swift J1818.0-1607
  84. AMON NuEM 240926A: Swift XRT Follow-up
  85. GRB 240930B: Fermi GBM Final Real-time Localization
  86. IPN triangulation of GRB 240926A
  87. GRB 240928A: SVOM/GRM observation
  88. GRB 240930A: Fermi GBM Final Real-time Localization
  89. GRB 240929A: Fermi GBM Final Real-time Localization
  90. IceCube-240929A - IceCube observation of a high-energy neutrino candidate track-like event
  91. Konus-Wind detection of GRB 240912A
  92. NuEm-240926A / IC240926A: BZQJ0955+4532 ~0.6m optical decay and rebrightening detection by MASTER
  93. GRB 240926A: SVOM/GRM observation
  94. Konus-Wind detection of GRB 240905B
  95. EP240918b and EP240918c: EP-FXT follow-up observations
  96. Insight-HXMT ToO observations of X-ray bursts from SGR 1E 1841-045 / Kes 73
  97. GRB 240716A: Swift/BAT-GUANO localization skymap of a long burst
  98. Konus-Wind detection of GRB 240918B
  99. IPN triangulation of GRB 240918B
  100. GRB 240905B: VZLUSAT-2 detection

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