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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"

36290 results found.

  1. GRB 240809B: MAXI/GSC detection
  2. GRB 240809A: Swift/UVOT Detection
  3. GRB 240809A: Tentative redshift from NOT
  4. GRB 240809A: Swift-XRT refined Analysis
  5. IPN triangulation of GRB 240807A / EP 240807a
  6. Swift GRB 240809A: Global MASTER-Net observations report
  7. GRB 240809A: JinShan optical observations
  8. GRB 240809A: Enhanced Swift-XRT position
  9. GRB 240809A: Skynet & Photon Ranch Optical Afterglow Observations
  10. GRB 240809A: SVOM/GRM observation
  11. GRB 240808A: SVOM/GRM observation
  12. GRB 240807A: SVOM/GRM observation
  13. GRB 240809A: Swift detection of a burst with a bright optical counterpart
  14. EP-WXT trigger 01709018832: SVOM/C-GFT observations of the star flare
  15. GRB 240807B: AstroSat CZTI detection of a short burst
  16. GRB 240801A: GRBAlpha detection
  17. GRB 240807B: Fermi GBM Final Localization
  18. GRB 240710B: VZLUSAT-2 detection
  19. GRB 240805A: ATCA Radio Upper Limits
  20. EP240807a/GRB 240807A: EP-FXT detection of the X-ray emission
  21. EP-WXT trigger 01709018832: KAIT optical observations of the star flare
  22. EP240802a/GRB240802A: KAIT optical upper limit
  23. GRB 240720B: VZLUSAT-2 detection
  24. GRB 240710A: VZLUSAT-2 detection
  25. GRB 240807A: Fermi GBM Final Localization
  26. GRB 240805B: GIT optical upper limit
  27. EP240806a: KAIT optical observations
  28. GRB 240805B: Swift-BAT refined analysis
  29. GRB 240805A: Swift-BAT refined analysis
  30. EP240804a (GRB 240804B): NOT optical observations
  31. Konus-Wind detection of GRB 240802A (EP240802a)
  32. Improved IPN triangulation of GRB 240802A / EP 240802a
  33. Konus-Wind detection of GRB 240805A
  34. GRB 240805B Bassano Bresciano Observatory upper limit
  35. GRB240805A: Fermi GBM Observation
  36. GRB 240805B: JinShan optical afterglow detection
  37. GRB 240804B/EP240804a: Correction to the GRB name in GCN 37071
  38. GRB 240805B: AbAO, CrAO, and Terskol optical upper limits
  39. Konus-Wind detection of GRB 240804B (a counterpart of EP240804a)
  40. Fermi Gamma-ray Burst Monitor trigger 240806402/744629911 is not a GRB
  41. GRB 240626B: VZLUSAT-2 detection
  42. GRB 240624B: VZLUSAT-2 detection
  43. GRB 240619C: VZLUSAT-2 detection
  44. EP 240806A: LCO optical observations
  45. GRB 240805B: Optical detection with 1.6m Mephisto
  46. GRB 240805B: NUTTelA-TAO / BSTI Optical Limits
  47. GRB 240805B: Swift-XRT refined Analysis
  48. GRB 240805B: Swift/UVOT Upper Limits
  49. GRB 240805A: Swift/UVOT Upper Limits
  50. GRB 240805B: BTA optical afterglow candidate
  51. GRB 240805A: SVOM/GRM observation
  52. GRB 240805B: Enhanced Swift-XRT position
  53. GRB 240805B: LCOGT Optical Upper Limits
  54. Swift GRB 240805B: Global MASTER-Net observations report
  55. GRB 240805B: JinShan optical upper limits
  56. Fermi GRB 240805A: Global MASTER-Net observations report
  57. Swift GRB 240805A: Global MASTER-Net observations report
  58. Fermi Gamma-ray Burst Monitor trigger 744558410/240805574 is not a GRB
  59. GRB 240805A: Swift-XRT refined Analysis
  60. GRB 240805B: Swift detection of a burst
  61. GRB 240805A: Fermi-LAT detection
  62. GRB 240805A: INTEGRAL spectral analysis
  63. EP240801a: Continued optical observations at ZTSh (CraO)
  64. GRB 240805A: A long GRB detected by INTEGRAL
  65. GRB 240805A: Swift detection of a burst
  66. GRB 240805A: Fermi GBM Final Real-time Localization
  67. Fermi GRB 240804A: Global MASTER-Net observations report
  68. EP240802a: Montarrenti Observatory optical upper limit
  69. GRB 240804A: Fermi GBM Final Real-time Localization
  70. IPN triangulation of GRB 240802A / EP 240802a
  71. Fermi Gamma-ray Burst Monitor trigger 744459130/240804425 is not a GRB
  72. EP240802A: Bassano Bresciano Observatory upper limit
  73. GRB 240802A: SVOM/GRM observation
  74. EP240802a: Time coincidence with GRB 240802A and optical upper limits with Kinder observations
  75. GRB 240802A: AstroSat CZTI detection of a long burst
  76. EP240801a: further SAO RAS optical observations
  77. EP240801a: optical observations at CrAO and AbAO
  78. EP240801a: Leavitt Observatory optical observations
  79. EP240801a: SAO RAS optical observations
  80. GRB 240801B: AstroSat CZTI Updated classification - likely a solar flare
  81. GRB 240727C: SVOM/GRM observation
  82. Fermi GBM trigger 744179961 / 240801194 can not be confirmed as a GRB
  83. GRB 240730A: Swift-BAT refined analysis
  84. EP240801a: KAIT optical counterpart observations
  85. GRB 240801B: AstroSat CZTI detection of a bright long burst
  86. Fermi GRB 240801A: Global MASTER-Net observations report
  87. GRB 240801A: Fermi GBM Final Real-time Localization
  88. GRB 240730C: AstroSat CZTI detection of a long burst
  89. GRB 240731A: Fermi GBM Final Localization
  90. GRB 240731A: AstroSat CZTI detection
  91. GRB 240730A: Osservatorio Astronomico Nastro Verde upper limit
  92. GRB240730A: BOOTES-5/JGT early optical upper limit
  93. Fermi Gamma-ray Burst Monitor trigger 744061103/240730818 is not a GRB
  94. Fermi GRB 240730B: Global MASTER-Net observations report
  95. GRB 240730B: Fermi GBM Final Real-time Localization
  96. Swift GRB 240730A: Global MASTER-Net observations report
  97. GRB 240730A: Swift-XRT refined Analysis
  98. GRB 240715A: Swift-XRT afterglow detection
  99. GRB 240730A: KAIT Optical Upper Limit
  100. GRB 240727C: GRBAlpha detection

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