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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"

37335 results found.

  1. GRB 240905E: SVOM/GRM observation
  2. GRB 240905E: LCOGT Optical Upper Limit
  3. GRB 240905E: Swift/UVOT Upper Limits
  4. GRB 240905E: SAO RAS optical upper limit
  5. GRB 240825A: Montarrenti Observatory optical follow-up observations
  6. GRB 240905E: Nanshan/HMT optical upper limit
  7. Swift GRB 240905E: Global MASTER-Net observations report
  8. GRB 240905E: Swift detection of a burst
  9. GRB 240819A: Optical upper limits from TESS
  10. GRB 240905D: AstroSat CZTI detection
  11. GRB 240905A: SVOM/GRM observation
  12. Fermi GRB 240905B: Global MASTER-Net observations report
  13. GRB 240905D: Fermi GBM Final Real-time Localization
  14. GRB 240905B: AstroSat CZTI detection and localization
  15. GRB 240905C: Fermi GBM Final Real-time Localization
  16. GRB 240905B: Fermi GBM Final Real-time Localization
  17. GRB 240825A: ATCA Detection of Radio Counterpart
  18. Swift GRB 240904A: Global MASTER-Net observations report
  19. GRB 240905A: Fermi GBM Final Real-time Localization
  20. Fermi Gamma-ray Burst Monitor trigger 747163821/240904729 is not a GRB
  21. GRB 240904A: Swift detection of a burst
  22. GRB 240828A: SVOM/GRM observation
  23. LIGO/Virgo/KAGRA S240825ar: Upper limits from Swift/BAT-GUANO
  24. LIGO/Virgo/KAGRA S240807h: Upper limits from Swift/BAT-GUANO
  25. Fermi Gamma-ray Burst Monitor trigger 240831A is not a GRB
  26. GRB 240828A: GECAM detection
  27. GRB 240831B: Fermi GBM Final Localization
  28. Fermi Gamma-ray Burst Monitor trigger 746882332/240901471 is not a GRB
  29. GRB 240825A: Magnitude Correction in SVOM/C-GFT Optical Observations
  30. GRB 240825A: MeerLICHT afterglow detection
  31. GRB 240828A: SAO RAS AS-500(2) optical observations
  32. GRB 240821A: VLT spectroscopic observations
  33. GRB 240825A: TSHAO Optical Upper Limit
  34. GRB 240829B: GRBAlpha detection
  35. GRB240828B: REM optical/NIR upper limits
  36. GRB 240828B: AbAO optical upper limit
  37. GRB 240831A: Fermi GBM Final Real-time Localization
  38. GRB 240825A: SOAR observations
  39. GRB 240828B: Mephisto optical upper limit
  40. GRB 240828B: GRANDMA Optical Upper Limit
  41. LIGO/Virgo/KAGRA S240830gn: Coverage and upper limits from MAXI/GSC observations
  42. GRB 240829A: Swift-BAT refined analysis
  43. GRB 240825A: Swift-BAT refined analysis
  44. GRB 240825A: MeerKAT detection
  45. GRB 240828B: J-band upper limit from WINTER
  46. GRB 240828B: GMG Optical Upper Limit
  47. GRB 240828A: KAIT continued optical observations
  48. GRB 240828B: GWAC-F50A optical upper limit
  49. GRB 240828B: SVOM/C-GFT optical upper limit
  50. GRB 240828B: SAO RAS optical upper limit
  51. GRB 240828B: KAIT optical upper limit
  52. GRB 240828A: SAO RAS optical observations
  53. GRB 240829B: Fermi GBM Final Localization
  54. GRB 240828A: Fermi GBM Observation
  55. GRB 240629A: First GRB Detected by BurstCube
  56. GRB 240828A: KAIT Optical Afterglow Candidate
  57. GRB 240825A: SVOM/VT optical detection
  58. GRB 240828A: Swift-XRT afterglow detection
  59. GRB 240825A: further SAO RAS optical observations
  60. GRB 240825A: iTelescope optical observations
  61. GRB 240828B: Swift-XRT afterglow detection
  62. GRB 240829A: Swift detection of a burst
  63. GRB 240828A: Fermi-LAT detection
  64. GRB 240828A: Tiled Swift observations
  65. GRB 240828A: AstroSat CZTI detection of a long burst
  66. Fermi GRB 240828A: Bassano Bresciano Observatory upper limit
  67. GRB 240825A: Upper limits from a neutrino search with IceCube
  68. GRB 240819A as a likely X-Ray Flash
  69. GRB 240828B: Swift ToO observations
  70. GRB 240821A: PRIME near-infrared observations
  71. GRB 240825A: VLA detection
  72. Fermi GRB 240828A: Global MASTER-Net observations report
  73. SVOM GRB 240821A: optical afterglow discovery
  74. GRB 240828B : Detection of a possible very soft X-ray transient by SVOM/ECLAIRs
  75. GRB 240828A: Fermi GBM Final Real-time Localization
  76. GRB 240821A: the second and third EP-FXT follow-up observations and afterglow candidates
  77. GRB 240825A: GECAM detection
  78. GRB 240825A: ALMA detection
  79. GRB 240825A: SAO RAS optical observations
  80. GRB 240824A: GIT optical upper limit
  81. GRB 240819A: Swift afterglow confirmation
  82. GRB 240825A: TNG optical photometry and spectroscopy
  83. GRB 240825A: NUTTelA-TAO / BSTI Optical Limits
  84. GRB 240825A: GMG Continued Optical Observation on the Second Night
  85. GRB 240824B: Ondrejov D50 optical limit
  86. GRB 240825A: KAIT optical observations
  87. GRB 240825A: PRIME near-infrared detection
  88. Konus-Wind detection of GRB 240825A (bright/long)
  89. GRB 240825A: Fermi GBM Observation
  90. GRB 240825A : MISTRAL/T193 OHP optical follow-up of the afterglow
  91. GRB 240825A: AKO Optical Follow-Up Observations
  92. GRB 240825A: AstroSat CZTI detection of the long bright burst
  93. GRB 240825A: Swift/UVOT Detection
  94. GRB 240825A: REM detection of the optical/NIR afterglow
  95. GRB 240825A: Swift-XRT refined Analysis
  96. GRB 240825A: VLT/X-shooter redshift
  97. GRB 240825A: SVOM/C-GFT optical observations
  98. GRB 240825A: Montarrenti Observatory optical observations
  99. GRB 240825A: Enhanced Swift-XRT position
  100. GRB 240825A: MASTER optical counterpart observation

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