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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"

21010 results found.

  1. GRB 240912A: Swift/UVOT Detection
  2. GRB 240911A: GOTO optical limits on Swift/XRT candidates
  3. Fermi trigger No 747920561: Global MASTER-Net observations report
  4. GRB 240911A: Swift-XRT observations
  5. Fermi GRB 240913A: Global MASTER-Net observations report
  6. GRB 240912A: J-band observations with WINTER
  7. Swift GRB 240912A: Global MASTER-Net observations report
  8. GRB 240912A: LCOGT detection and Legacy Surveys likely host galaxy
  9. GRB 240911A: Tiled Swift observations
  10. GRB 240912A : INTEGRAL SPI ACS LIGHT CURVE
  11. GRB 240912A: Redshift from OSIRIS+/GTC
  12. Fast X-ray Transient EP240801a: GMRT radio observations
  13. GRB 240910A: NOT optical observations
  14. GRB 240910A: Swift-XRT detection of GOTO24fvl/AT2024vfp
  15. GRB 240910A: JinShan optical observations
  16. GRB 240910A: GOTO candidate optical counterpart
  17. EP240908a: Optical afterglow confirmation
  18. GRB 240910A: Swift ToO observations
  19. GRB 240825A: 7DT Optical Upper Limit
  20. GRB 240905E: SVOM/VT optical observations
  21. GRB 240905E: SVOM/VT optical observations (duplicate submission of GCN 37453)
  22. LIGO/Virgo/KAGRA S240910ci: NED Galaxies in the Localization Volume
  23. LIGO/Virgo/KAGRA S240910ci: Coverage and upper limits from MAXI/GSC observations
  24. EP240908a: Mondy and AbAO follow-up observations
  25. EP240908a: Updates on the WXT detection result around the trigger time
  26. Fermi GRB 240910A: Global MASTER-Net observations report
  27. EP240908a: optical afterglow candidate
  28. EP EP240908a: Global MASTER-Net observations report
  29. Fermi trigger No 747553301: Global MASTER-Net observations report
  30. EP240908a: TRT optical upper limit
  31. GRB 240905B: GOTO optical upper limits
  32. EP240908a: EP detection of a fast X-ray transient
  33. Fermi GRB 240908A: Global MASTER-Net observations report
  34. GRB 240905E: GIT optical upper limit
  35. GRB 240905B: Swift-XRT observations
  36. GRB 240905E: Gaoyazi/GOT optical upper limits
  37. GRB 240905E: NUTTelA-TAO / BSTI Optical Limits
  38. GRB 240905B: Swift ToO observations
  39. GRB 240905E: J-band observations with WINTER
  40. GRB 240905E: CrAO Optical Afterglow observations, possible OT candidate
  41. Fermi GRB 240905D: Global MASTER-Net observations report
  42. Fermi GRB 240905A: Global MASTER-Net observations report
  43. GRB 240905E: REM optical/NIR upper limits
  44. GRB 240905E: Swift/UVOT Upper Limits
  45. GRB 240905E: SAO RAS optical upper limit
  46. GRB 240825A: Montarrenti Observatory optical follow-up observations
  47. GRB 240905E: Nanshan/HMT optical upper limit
  48. Swift GRB 240905E: Global MASTER-Net observations report
  49. Fermi GRB 240905B: Global MASTER-Net observations report
  50. GRB 240825A: ATCA Detection of Radio Counterpart
  51. Swift GRB 240904A: Global MASTER-Net observations report
  52. Fermi trigger No 747163821: Global MASTER-Net observations report
  53. GRB 240825A: Magnitude Correction in SVOM/C-GFT Optical Observations
  54. GRB 240825A: MeerLICHT afterglow detection
  55. Fermi trigger No 746923430: Global MASTER-Net observations report
  56. GRB 240828A: SAO RAS AS-500(2) optical observations
  57. GRB 240821A: VLT spectroscopic observations
  58. Fermi trigger No 746882332: Global MASTER-Net observations report
  59. GRB240828B: REM optical/NIR upper limits
  60. Fermi trigger No 746816563: Global MASTER-Net observations report
  61. GRB 240825A: SOAR observations
  62. GRB 240828B: Mephisto optical upper limit
  63. GRB 240828B: GRANDMA Optical Upper Limit
  64. LIGO/Virgo/KAGRA S240830gn: Coverage and upper limits from MAXI/GSC observations
  65. GRB 240825A: MeerKAT detection
  66. GRB 240828B: J-band upper limit from WINTER
  67. Fermi trigger No 746684112: Global MASTER-Net observations report
  68. GRB 240828A: KAIT continued optical observations
  69. GRB 240828A: SAO RAS optical observations
  70. Fermi trigger No 746587425: Global MASTER-Net observations report
  71. GRB 240828A: KAIT Optical Afterglow Candidate
  72. GRB 240825A: SVOM/VT optical detection
  73. GRB 240828A: Swift-XRT afterglow detection
  74. GRB 240825A: further SAO RAS optical observations
  75. GRB 240825A: iTelescope optical observations
  76. GRB 240828B: Swift-XRT afterglow detection
  77. Swift GRB240829.16: Global MASTER-Net observations report
  78. GRB 240828A: Tiled Swift observations
  79. LAT GRB240828.62: Global MASTER-Net observations report
  80. Fermi GRB 240828A: Bassano Bresciano Observatory upper limit
  81. GRB 240819A as a likely X-Ray Flash
  82. GRB 240828B: Swift ToO observations
  83. GRB 240821A: PRIME near-infrared observations
  84. GRB 240825A: VLA detection
  85. Fermi GRB 240828A: Global MASTER-Net observations report
  86. Fermi trigger No 746438824: Global MASTER-Net observations report
  87. SVOM GRB 240821A: optical afterglow discovery
  88. GRB 240821A: the second and third EP-FXT follow-up observations and afterglow candidates
  89. GRB 240825A: ALMA detection
  90. GRB 240825A: SAO RAS optical observations
  91. GRB 240824A: GIT optical upper limit
  92. GRB 240825A: TNG optical photometry and spectroscopy
  93. GRB 240825A: NUTTelA-TAO / BSTI Optical Limits
  94. GRB 240825A: GMG Continued Optical Observation on the Second Night
  95. GRB 240825A: KAIT optical observations
  96. GRB 240825A: PRIME near-infrared detection
  97. GRB 240825A: AKO Optical Follow-Up Observations
  98. GRB 240825A: Swift/UVOT Detection
  99. GRB 240825A: REM detection of the optical/NIR afterglow
  100. GRB 240825A: SVOM/C-GFT optical observations

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