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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"

36197 results found.

  1. Swift GRB 240912A: Global MASTER-Net observations report
  2. GRB 240912A: LCOGT detection and Legacy Surveys likely host galaxy
  3. GRB 240911A: Tiled Swift observations
  4. Fermi Gamma-ray Burst Monitor trigger 747839931/240912555 is not a GRB
  5. GRB 240912A : INTEGRAL SPI ACS LIGHT CURVE
  6. GRB 240912B: Fermi GBM Final Real-time Localization
  7. GRB 240912A: NOT optical spectroscopy
  8. GRB 240912A: Enhanced Swift-XRT position
  9. GRB 240912A: Redshift from OSIRIS+/GTC
  10. GRB 240910A: Redshift from OSIRIS+/GTC
  11. GRB 240912A: Swift detection of a burst with an optical counterpart
  12. GRB 240912A: Fermi GBM Final Real-time Localization
  13. GRB 240910A: Fermi GBM Observation
  14. GRB 240910A: NOT optical observations
  15. GRB 240911A : a likely weak GRB detected by SVOM/ECLAIRs
  16. GRB 240910A: Swift-XRT detection of GOTO24fvl/AT2024vfp
  17. GRB 240910A: JinShan optical observations
  18. GRB 240910A: GOTO candidate optical counterpart
  19. GRB 240710A: SVOM/GRM observation
  20. GRB 240910A: Swift ToO observations
  21. IPN triangulation of GRB 240905B (short)
  22. GRB 240825A: 7DT Optical Upper Limit
  23. GRB 240905E: SVOM/VT optical observations
  24. GRB 240905E: SVOM/VT optical observations (duplicate submission of GCN 37453)
  25. GRB 240910A: GRBAlpha detection
  26. GRB 240910B: Fermi GBM Final Real-time Localization
  27. GRB 240910A: SVOM/GRM observation
  28. EP240908a: Mondy and AbAO follow-up observations
  29. Fermi GRB 240910A: Global MASTER-Net observations report
  30. GRB 240910A: Fermi GBM Final Real-time Localization
  31. LIGO/Virgo/KAGRA S240908bs: Upper limits from Swift/BAT-GUANO
  32. LIGO/Virgo/KAGRA S240907cg: Upper limits from Swift/BAT-GUANO
  33. GRB 240905B: Fermi GBM Observation
  34. GRB 240905B: GOTO optical upper limits
  35. Fermi GRB 240908A: Global MASTER-Net observations report
  36. GRB 240908A: Fermi GBM Final Real-time Localization
  37. GRB 240801A: SVOM/GRM observation
  38. GRB 240905E: GIT optical upper limit
  39. GRB 240905B: Swift-XRT observations
  40. GRB 240905E: Gaoyazi/GOT optical upper limits
  41. GRB 240905E: NUTTelA-TAO / BSTI Optical Limits
  42. GRB 240905B: Fermi-LAT detection
  43. GRB 240905B: Swift ToO observations
  44. GRB 240905E: J-band observations with WINTER
  45. GRB 240905E: CrAO Optical Afterglow observations, possible OT candidate
  46. GRB 240905E: AKO Optical Upper Limit
  47. GRB 240905E: SVOM/C-GFT optical upper limit
  48. GRB 240905E: OHP/MISTRAL T193 optical upper limit
  49. Fermi GRB 240905D: Global MASTER-Net observations report
  50. Fermi GRB 240905A: Global MASTER-Net observations report
  51. GRB 240905E: NOT optical upper limits
  52. GRB 240905E: REM optical/NIR upper limits
  53. GRB 240902B: AstroSat CZTI detection of a long burst
  54. GRB 240905E: Swift-XRT refined Analysis
  55. GRB 240902A: AstroSat CZTI detection of a long burst
  56. GRB 240905E: SVOM/GRM observation
  57. GRB 240905E: LCOGT Optical Upper Limit
  58. GRB 240905E: Swift/UVOT Upper Limits
  59. GRB 240905E: SAO RAS optical upper limit
  60. GRB 240825A: Montarrenti Observatory optical follow-up observations
  61. GRB 240905E: Nanshan/HMT optical upper limit
  62. Swift GRB 240905E: Global MASTER-Net observations report
  63. GRB 240905E: Swift detection of a burst
  64. GRB 240819A: Optical upper limits from TESS
  65. GRB 240905D: AstroSat CZTI detection
  66. GRB 240905A: SVOM/GRM observation
  67. Fermi GRB 240905B: Global MASTER-Net observations report
  68. GRB 240905D: Fermi GBM Final Real-time Localization
  69. GRB 240905B: AstroSat CZTI detection and localization
  70. GRB 240905C: Fermi GBM Final Real-time Localization
  71. GRB 240905B: Fermi GBM Final Real-time Localization
  72. GRB 240825A: ATCA Detection of Radio Counterpart
  73. Swift GRB 240904A: Global MASTER-Net observations report
  74. GRB 240905A: Fermi GBM Final Real-time Localization
  75. Fermi Gamma-ray Burst Monitor trigger 747163821/240904729 is not a GRB
  76. GRB 240904A: Swift detection of a burst
  77. GRB 240828A: SVOM/GRM observation
  78. LIGO/Virgo/KAGRA S240825ar: Upper limits from Swift/BAT-GUANO
  79. LIGO/Virgo/KAGRA S240807h: Upper limits from Swift/BAT-GUANO
  80. Fermi Gamma-ray Burst Monitor trigger 240831A is not a GRB
  81. GRB 240828A: GECAM detection
  82. GRB 240831B: Fermi GBM Final Localization
  83. Fermi Gamma-ray Burst Monitor trigger 746882332/240901471 is not a GRB
  84. GRB 240825A: Magnitude Correction in SVOM/C-GFT Optical Observations
  85. GRB 240825A: MeerLICHT afterglow detection
  86. GRB 240828A: SAO RAS AS-500(2) optical observations
  87. GRB 240821A: VLT spectroscopic observations
  88. GRB 240825A: TSHAO Optical Upper Limit
  89. GRB 240829B: GRBAlpha detection
  90. GRB240828B: REM optical/NIR upper limits
  91. GRB 240828B: AbAO optical upper limit
  92. GRB 240831A: Fermi GBM Final Real-time Localization
  93. GRB 240825A: SOAR observations
  94. GRB 240828B: Mephisto optical upper limit
  95. GRB 240828B: GRANDMA Optical Upper Limit
  96. GRB 240829A: Swift-BAT refined analysis
  97. GRB 240825A: Swift-BAT refined analysis
  98. GRB 240825A: MeerKAT detection
  99. GRB 240828B: J-band upper limit from WINTER
  100. GRB 240828B: GMG Optical Upper Limit

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