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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"

36405 results found.

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

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