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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"

36404 results found.

  1. GRB 240809A: SVOM/GRM observation
  2. GRB 240808A: SVOM/GRM observation
  3. GRB 240807A: SVOM/GRM observation
  4. GRB 240809A: Swift detection of a burst with a bright optical counterpart
  5. EP-WXT trigger 01709018832: SVOM/C-GFT observations of the star flare
  6. EP240807a: STEP/T80S optical limits
  7. GRB 240807B: AstroSat CZTI detection of a short burst
  8. GRB 240801A: GRBAlpha detection
  9. GRB 240807B: Fermi GBM Final Localization
  10. GRB 240710B: VZLUSAT-2 detection
  11. GRB 240805A: ATCA Radio Upper Limits
  12. EP240807a/GRB 240807A: EP-FXT detection of the X-ray emission
  13. EP-WXT trigger 01709018832: KAIT optical observations of the star flare
  14. EP240802a/GRB240802A: KAIT optical upper limit
  15. GRB 240720B: VZLUSAT-2 detection
  16. GRB 240710A: VZLUSAT-2 detection
  17. GRB 240807A: Fermi GBM Final Localization
  18. GRB 240805B: GIT optical upper limit
  19. EP240806a: KAIT optical observations
  20. GRB 240805B: Swift-BAT refined analysis
  21. GRB 240805A: Swift-BAT refined analysis
  22. EP240804a (GRB 240804B): NOT optical observations
  23. Konus-Wind detection of GRB 240802A (EP240802a)
  24. Improved IPN triangulation of GRB 240802A / EP 240802a
  25. Konus-Wind detection of GRB 240805A
  26. GRB 240805B Bassano Bresciano Observatory upper limit
  27. GRB240805A: Fermi GBM Observation
  28. GRB 240805B: JinShan optical afterglow detection
  29. GRB 240804B/EP240804a: Correction to the GRB name in GCN 37071
  30. GRB 240805B: AbAO, CrAO, and Terskol optical upper limits
  31. Konus-Wind detection of GRB 240804B (a counterpart of EP240804a)
  32. Fermi Gamma-ray Burst Monitor trigger 240806402/744629911 is not a GRB
  33. GRB 240626B: VZLUSAT-2 detection
  34. GRB 240624B: VZLUSAT-2 detection
  35. GRB 240619C: VZLUSAT-2 detection
  36. EP 240806A: LCO optical observations
  37. GRB 240805B: Optical detection with 1.6m Mephisto
  38. GRB 240805B: NUTTelA-TAO / BSTI Optical Limits
  39. GRB 240805B: Swift-XRT refined Analysis
  40. GRB 240805B: Swift/UVOT Upper Limits
  41. GRB 240805A: Swift/UVOT Upper Limits
  42. GRB 240805B: BTA optical afterglow candidate
  43. GRB 240805A: SVOM/GRM observation
  44. GRB 240805B: Enhanced Swift-XRT position
  45. GRB 240805B: LCOGT Optical Upper Limits
  46. Swift GRB 240805B: Global MASTER-Net observations report
  47. GRB 240805B: JinShan optical upper limits
  48. Fermi GRB 240805A: Global MASTER-Net observations report
  49. Swift GRB 240805A: Global MASTER-Net observations report
  50. Fermi Gamma-ray Burst Monitor trigger 744558410/240805574 is not a GRB
  51. GRB 240805A: Swift-XRT refined Analysis
  52. GRB 240805B: Swift detection of a burst
  53. GRB 240805A: Fermi-LAT detection
  54. GRB 240805A: INTEGRAL spectral analysis
  55. EP240801a: Continued optical observations at ZTSh (CraO)
  56. GRB 240805A: A long GRB detected by INTEGRAL
  57. GRB 240805A: Swift detection of a burst
  58. GRB 240805A: Fermi GBM Final Real-time Localization
  59. Fermi GRB 240804A: Global MASTER-Net observations report
  60. EP240802a: Montarrenti Observatory optical upper limit
  61. GRB 240804A: Fermi GBM Final Real-time Localization
  62. IPN triangulation of GRB 240802A / EP 240802a
  63. Fermi Gamma-ray Burst Monitor trigger 744459130/240804425 is not a GRB
  64. EP240802A: Bassano Bresciano Observatory upper limit
  65. GRB 240802A: SVOM/GRM observation
  66. EP240802a: Time coincidence with GRB 240802A and optical upper limits with Kinder observations
  67. GRB 240802A: AstroSat CZTI detection of a long burst
  68. EP240801a: further SAO RAS optical observations
  69. EP240801a: optical observations at CrAO and AbAO
  70. EP240801a: Leavitt Observatory optical observations
  71. EP240801a: SAO RAS optical observations
  72. GRB 240801B: AstroSat CZTI Updated classification - likely a solar flare
  73. GRB 240727C: SVOM/GRM observation
  74. Fermi GBM trigger 744179961 / 240801194 can not be confirmed as a GRB
  75. GRB 240730A: Swift-BAT refined analysis
  76. EP240801a: KAIT optical counterpart observations
  77. GRB 240801B: AstroSat CZTI detection of a bright long burst
  78. Fermi GRB 240801A: Global MASTER-Net observations report
  79. GRB 240801A: Fermi GBM Final Real-time Localization
  80. GRB 240730C: AstroSat CZTI detection of a long burst
  81. GRB 240731A: Fermi GBM Final Localization
  82. GRB 240731A: AstroSat CZTI detection
  83. GRB 240730A: Osservatorio Astronomico Nastro Verde upper limit
  84. GRB240730A: BOOTES-5/JGT early optical upper limit
  85. Fermi Gamma-ray Burst Monitor trigger 744061103/240730818 is not a GRB
  86. Fermi GRB 240730B: Global MASTER-Net observations report
  87. GRB 240730B: Fermi GBM Final Real-time Localization
  88. Swift GRB 240730A: Global MASTER-Net observations report
  89. GRB 240730A: Swift-XRT refined Analysis
  90. GRB 240715A: Swift-XRT afterglow detection
  91. GRB 240730A: KAIT Optical Upper Limit
  92. GRB 240727C: GRBAlpha detection
  93. GRB 240730A: Swift/UVOT Upper Limits
  94. GRB 240730A: Enhanced Swift-XRT position
  95. GRB 240730A: Swift detection of a burst
  96. GRB 240727A: Swift-BAT refined analysis
  97. Fermi Gamma-ray Burst Monitor trigger 743953682/240729575 is not a GRB
  98. GRB 240727A: observations of optical counterpart.
  99. GRB 240727B: Swift-XRT observations
  100. Fermi GRB 240727A: Global MASTER-Net observations report

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