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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"

36423 results found.

  1. GRB 240811A: Swift detection of a burst
  2. Fermi Gamma-ray Burst Monitor trigger 745050426/240811269 is not a GRB
  3. GRB 240810A: Fermi GBM Final Real-time Localization
  4. GRB 240809A: REM detection of the optical afterglow
  5. GRB 240809A: Bassano Bresciano Observatory optical observations
  6. Konus-Wind detection of GRB 240807A (a counterpart of EP240807a)
  7. GRB 240809A: Conclusive redshift from VLT
  8. GRB 240809A: KAIT optical observations
  9. GRB 240808A: AstroSat CZTI detection
  10. GRB 240809A: GIT afterglow observations
  11. GRB 240809B: MAXI/GSC detection
  12. GRB 240809A: Swift/UVOT Detection
  13. GRB 240809A: Tentative redshift from NOT
  14. GRB 240809A: Swift-XRT refined Analysis
  15. IPN triangulation of GRB 240807A / EP 240807a
  16. Swift GRB 240809A: Global MASTER-Net observations report
  17. GRB 240809A: JinShan optical observations
  18. GRB 240809A: Enhanced Swift-XRT position
  19. GRB 240809A: Skynet & Photon Ranch Optical Afterglow Observations
  20. GRB 240809A: SVOM/GRM observation
  21. GRB 240808A: SVOM/GRM observation
  22. GRB 240807A: SVOM/GRM observation
  23. GRB 240809A: Swift detection of a burst with a bright optical counterpart
  24. EP-WXT trigger 01709018832: SVOM/C-GFT observations of the star flare
  25. EP240807a: STEP/T80S optical limits
  26. GRB 240807B: AstroSat CZTI detection of a short burst
  27. GRB 240801A: GRBAlpha detection
  28. GRB 240807B: Fermi GBM Final Localization
  29. GRB 240710B: VZLUSAT-2 detection
  30. GRB 240805A: ATCA Radio Upper Limits
  31. EP240807a/GRB 240807A: EP-FXT detection of the X-ray emission
  32. EP-WXT trigger 01709018832: KAIT optical observations of the star flare
  33. EP240802a/GRB240802A: KAIT optical upper limit
  34. GRB 240720B: VZLUSAT-2 detection
  35. GRB 240710A: VZLUSAT-2 detection
  36. GRB 240807A: Fermi GBM Final Localization
  37. GRB 240805B: GIT optical upper limit
  38. EP240806a: KAIT optical observations
  39. GRB 240805B: Swift-BAT refined analysis
  40. GRB 240805A: Swift-BAT refined analysis
  41. EP240804a (GRB 240804B): NOT optical observations
  42. Konus-Wind detection of GRB 240802A (EP240802a)
  43. Improved IPN triangulation of GRB 240802A / EP 240802a
  44. Konus-Wind detection of GRB 240805A
  45. GRB 240805B Bassano Bresciano Observatory upper limit
  46. GRB240805A: Fermi GBM Observation
  47. GRB 240805B: JinShan optical afterglow detection
  48. GRB 240804B/EP240804a: Correction to the GRB name in GCN 37071
  49. GRB 240805B: AbAO, CrAO, and Terskol optical upper limits
  50. Konus-Wind detection of GRB 240804B (a counterpart of EP240804a)
  51. Fermi Gamma-ray Burst Monitor trigger 240806402/744629911 is not a GRB
  52. GRB 240626B: VZLUSAT-2 detection
  53. GRB 240624B: VZLUSAT-2 detection
  54. GRB 240619C: VZLUSAT-2 detection
  55. EP 240806A: LCO optical observations
  56. GRB 240805B: Optical detection with 1.6m Mephisto
  57. GRB 240805B: NUTTelA-TAO / BSTI Optical Limits
  58. GRB 240805B: Swift-XRT refined Analysis
  59. GRB 240805B: Swift/UVOT Upper Limits
  60. GRB 240805A: Swift/UVOT Upper Limits
  61. GRB 240805B: BTA optical afterglow candidate
  62. GRB 240805A: SVOM/GRM observation
  63. GRB 240805B: Enhanced Swift-XRT position
  64. GRB 240805B: LCOGT Optical Upper Limits
  65. Swift GRB 240805B: Global MASTER-Net observations report
  66. GRB 240805B: JinShan optical upper limits
  67. Fermi GRB 240805A: Global MASTER-Net observations report
  68. Swift GRB 240805A: Global MASTER-Net observations report
  69. Fermi Gamma-ray Burst Monitor trigger 744558410/240805574 is not a GRB
  70. GRB 240805A: Swift-XRT refined Analysis
  71. GRB 240805B: Swift detection of a burst
  72. GRB 240805A: Fermi-LAT detection
  73. GRB 240805A: INTEGRAL spectral analysis
  74. EP240801a: Continued optical observations at ZTSh (CraO)
  75. GRB 240805A: A long GRB detected by INTEGRAL
  76. GRB 240805A: Swift detection of a burst
  77. GRB 240805A: Fermi GBM Final Real-time Localization
  78. Fermi GRB 240804A: Global MASTER-Net observations report
  79. EP240802a: Montarrenti Observatory optical upper limit
  80. GRB 240804A: Fermi GBM Final Real-time Localization
  81. IPN triangulation of GRB 240802A / EP 240802a
  82. Fermi Gamma-ray Burst Monitor trigger 744459130/240804425 is not a GRB
  83. EP240802A: Bassano Bresciano Observatory upper limit
  84. GRB 240802A: SVOM/GRM observation
  85. EP240802a: Time coincidence with GRB 240802A and optical upper limits with Kinder observations
  86. GRB 240802A: AstroSat CZTI detection of a long burst
  87. EP240801a: further SAO RAS optical observations
  88. EP240801a: optical observations at CrAO and AbAO
  89. EP240801a: Leavitt Observatory optical observations
  90. EP240801a: SAO RAS optical observations
  91. GRB 240801B: AstroSat CZTI Updated classification - likely a solar flare
  92. GRB 240727C: SVOM/GRM observation
  93. Fermi GBM trigger 744179961 / 240801194 can not be confirmed as a GRB
  94. GRB 240730A: Swift-BAT refined analysis
  95. EP240801a: KAIT optical counterpart observations
  96. GRB 240801B: AstroSat CZTI detection of a bright long burst
  97. Fermi GRB 240801A: Global MASTER-Net observations report
  98. GRB 240801A: Fermi GBM Final Real-time Localization
  99. GRB 240730C: AstroSat CZTI detection of a long burst
  100. GRB 240731A: Fermi GBM Final Localization

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