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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"

32570 results found.

  1. GRB 240910A: JinShan optical observations
  2. GRB 240910A: GOTO candidate optical counterpart
  3. EP240908a: Optical afterglow confirmation
  4. GRB 240710A: SVOM/GRM observation
  5. GRB 240910A: Swift ToO observations
  6. IPN triangulation of GRB 240905B (short)
  7. GRB 240825A: 7DT Optical Upper Limit
  8. GRB 240905E: SVOM/VT optical observations
  9. GRB 240905E: SVOM/VT optical observations (duplicate submission of GCN 37453)
  10. GRB 240910A: GRBAlpha detection
  11. LIGO/Virgo/KAGRA S240910ci: Coverage and upper limits from MAXI/GSC observations
  12. LIGO/Virgo/KAGRA S240910ci: Updated Sky localization and EM Bright Classification
  13. LIGO/Virgo/KAGRA S240910ci: Identification of a GW compact binary merger candidate
  14. GRB 240910A: SVOM/GRM observation
  15. EP240908a: Mondy and AbAO follow-up observations
  16. EP240908a: Updates on the WXT detection result around the trigger time
  17. Fermi GRB 240910A: Global MASTER-Net observations report
  18. EP240908a: optical afterglow candidate
  19. EP EP240908a: Global MASTER-Net observations report
  20. GRB 240905B: Fermi GBM Observation
  21. EP240908a: TRT optical upper limit
  22. GRB 240905B: GOTO optical upper limits
  23. Fermi GRB 240908A: Global MASTER-Net observations report
  24. LIGO/Virgo/KAGRA S240908dg: Updated Sky localization
  25. LIGO/Virgo/KAGRA S240908bs: Updated Sky localization
  26. LIGO/Virgo/KAGRA S240908dg: Identification of a GW compact binary merger candidate
  27. LIGO/Virgo/KAGRA S240908bs: Identification of a GW compact binary merger candidate
  28. LIGO/Virgo/KAGRA S240907cg: Updated Sky localization
  29. GRB 240801A: SVOM/GRM observation
  30. LIGO/Virgo/KAGRA S240907cg: Identification of a GW compact binary merger candidate
  31. GRB 240905E: GIT optical upper limit
  32. GRB 240905E: Gaoyazi/GOT optical upper limits
  33. GRB 240905E: NUTTelA-TAO / BSTI Optical Limits
  34. GRB 240905B: Fermi-LAT detection
  35. GRB 240905B: Swift ToO observations
  36. GRB 240905E: J-band observations with WINTER
  37. GRB 240905E: CrAO Optical Afterglow observations, possible OT candidate
  38. GRB 240905E: AKO Optical Upper Limit
  39. GRB 240905E: SVOM/C-GFT optical upper limit
  40. GRB 240905E: OHP/MISTRAL T193 optical upper limit
  41. Fermi GRB 240905D: Global MASTER-Net observations report
  42. Fermi GRB 240905A: Global MASTER-Net observations report
  43. GRB 240905E: NOT optical upper limits
  44. GRB 240905E: REM optical/NIR upper limits
  45. GRB 240905E: SVOM/GRM observation
  46. GRB 240905E: LCOGT Optical Upper Limit
  47. GRB 240905E: Swift/UVOT Upper Limits
  48. GRB 240905E: SAO RAS optical upper limit
  49. GRB 240825A: Montarrenti Observatory optical follow-up observations
  50. GRB 240905E: Nanshan/HMT optical upper limit
  51. Swift GRB 240905E: Global MASTER-Net observations report
  52. GRB 240819A: Optical upper limits from TESS
  53. GRB 240905D: AstroSat CZTI detection
  54. GRB 240905A: SVOM/GRM observation
  55. Fermi GRB 240905B: Global MASTER-Net observations report
  56. GRB 240905B: AstroSat CZTI detection and localization
  57. GRB 240825A: ATCA Detection of Radio Counterpart
  58. Swift GRB 240904A: Global MASTER-Net observations report
  59. GRB 240828A: SVOM/GRM observation
  60. Fermi Gamma-ray Burst Monitor trigger 240831A is not a GRB
  61. LIGO/Virgo/KAGRA S240902bq: Updated Sky localization
  62. GRB 240828A: GECAM detection
  63. LIGO/Virgo/KAGRA S240902bq: Identification of a GW compact binary merger candidate
  64. GRB 240825A: Magnitude Correction in SVOM/C-GFT Optical Observations
  65. GRB 240825A: MeerLICHT afterglow detection
  66. GRB 240828A: SAO RAS AS-500(2) optical observations
  67. GRB 240821A: VLT spectroscopic observations
  68. GRB 240825A: TSHAO Optical Upper Limit
  69. GRB 240829B: GRBAlpha detection
  70. GRB240828B: REM optical/NIR upper limits
  71. GRB 240828B: AbAO optical upper limit
  72. GRB 240825A: SOAR observations
  73. GRB 240828B: Mephisto optical upper limit
  74. GRB 240828B: GRANDMA Optical Upper Limit
  75. LIGO/Virgo/KAGRA S240830gn: Coverage and upper limits from MAXI/GSC observations
  76. LIGO/Virgo/KAGRA S240830gn: Updated Sky localization and EM Bright Classification
  77. GRB 240829A: Swift-BAT refined analysis
  78. GRB 240825A: Swift-BAT refined analysis
  79. LIGO/Virgo/KAGRA S240830gn: Identification of a GW compact binary merger candidate
  80. GRB 240825A: MeerKAT detection
  81. GRB 240828B: J-band upper limit from WINTER
  82. GRB 240828B: GMG Optical Upper Limit
  83. GRB 240828A: KAIT continued optical observations
  84. GRB 240828B: GWAC-F50A optical upper limit
  85. GRB 240828B: SVOM/C-GFT optical upper limit
  86. GRB 240828B: SAO RAS optical upper limit
  87. GRB 240828B: KAIT optical upper limit
  88. GRB 240828A: SAO RAS optical observations
  89. GRB 240828A: Fermi GBM Observation
  90. GRB 240629A: First GRB Detected by BurstCube
  91. GRB 240828A: KAIT Optical Afterglow Candidate
  92. GRB 240825A: SVOM/VT optical detection
  93. GRB 240825A: further SAO RAS optical observations
  94. GRB 240825A: iTelescope optical observations
  95. GRB 240828A: Fermi-LAT detection
  96. GRB 240828A: Tiled Swift observations
  97. GRB 240828A: AstroSat CZTI detection of a long burst
  98. GRB 240825A: Upper limits from a neutrino search with IceCube
  99. GRB 240819A as a likely X-Ray Flash
  100. GRB 240828B: Swift ToO observations

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