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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. EP240807a/GRB 240807A: EP-FXT detection of the X-ray emission
  2. EP-WXT trigger 01709018832: KAIT optical observations of the star flare
  3. EP240802a/GRB240802A: KAIT optical upper limit
  4. GRB 240720B: VZLUSAT-2 detection
  5. GRB 240710A: VZLUSAT-2 detection
  6. GRB 240807A: Fermi GBM Final Localization
  7. GRB 240805B: GIT optical upper limit
  8. EP240806a: KAIT optical observations
  9. GRB 240805B: Swift-BAT refined analysis
  10. GRB 240805A: Swift-BAT refined analysis
  11. EP240804a (GRB 240804B): NOT optical observations
  12. Konus-Wind detection of GRB 240802A (EP240802a)
  13. Improved IPN triangulation of GRB 240802A / EP 240802a
  14. Konus-Wind detection of GRB 240805A
  15. GRB 240805B Bassano Bresciano Observatory upper limit
  16. GRB240805A: Fermi GBM Observation
  17. GRB 240805B: JinShan optical afterglow detection
  18. GRB 240804B/EP240804a: Correction to the GRB name in GCN 37071
  19. GRB 240805B: AbAO, CrAO, and Terskol optical upper limits
  20. Konus-Wind detection of GRB 240804B (a counterpart of EP240804a)
  21. Fermi Gamma-ray Burst Monitor trigger 240806402/744629911 is not a GRB
  22. GRB 240626B: VZLUSAT-2 detection
  23. GRB 240624B: VZLUSAT-2 detection
  24. GRB 240619C: VZLUSAT-2 detection
  25. EP 240806A: LCO optical observations
  26. GRB 240805B: Optical detection with 1.6m Mephisto
  27. GRB 240805B: NUTTelA-TAO / BSTI Optical Limits
  28. GRB 240805B: Swift-XRT refined Analysis
  29. GRB 240805B: Swift/UVOT Upper Limits
  30. GRB 240805A: Swift/UVOT Upper Limits
  31. GRB 240805B: BTA optical afterglow candidate
  32. GRB 240805A: SVOM/GRM observation
  33. GRB 240805B: Enhanced Swift-XRT position
  34. GRB 240805B: LCOGT Optical Upper Limits
  35. Swift GRB 240805B: Global MASTER-Net observations report
  36. GRB 240805B: JinShan optical upper limits
  37. Fermi GRB 240805A: Global MASTER-Net observations report
  38. Swift GRB 240805A: Global MASTER-Net observations report
  39. Fermi Gamma-ray Burst Monitor trigger 744558410/240805574 is not a GRB
  40. GRB 240805A: Swift-XRT refined Analysis
  41. GRB 240805B: Swift detection of a burst
  42. GRB 240805A: Fermi-LAT detection
  43. GRB 240805A: INTEGRAL spectral analysis
  44. EP240801a: Continued optical observations at ZTSh (CraO)
  45. GRB 240805A: A long GRB detected by INTEGRAL
  46. GRB 240805A: Swift detection of a burst
  47. GRB 240805A: Fermi GBM Final Real-time Localization
  48. Fermi GRB 240804A: Global MASTER-Net observations report
  49. EP240802a: Montarrenti Observatory optical upper limit
  50. GRB 240804A: Fermi GBM Final Real-time Localization
  51. IPN triangulation of GRB 240802A / EP 240802a
  52. Fermi Gamma-ray Burst Monitor trigger 744459130/240804425 is not a GRB
  53. EP240802A: Bassano Bresciano Observatory upper limit
  54. GRB 240802A: SVOM/GRM observation
  55. EP240802a: Time coincidence with GRB 240802A and optical upper limits with Kinder observations
  56. GRB 240802A: AstroSat CZTI detection of a long burst
  57. EP240801a: further SAO RAS optical observations
  58. EP240801a: optical observations at CrAO and AbAO
  59. EP240801a: Leavitt Observatory optical observations
  60. EP240801a: SAO RAS optical observations
  61. GRB 240801B: AstroSat CZTI Updated classification - likely a solar flare
  62. GRB 240727C: SVOM/GRM observation
  63. Fermi GBM trigger 744179961 / 240801194 can not be confirmed as a GRB
  64. GRB 240730A: Swift-BAT refined analysis
  65. EP240801a: KAIT optical counterpart observations
  66. GRB 240801B: AstroSat CZTI detection of a bright long burst
  67. Fermi GRB 240801A: Global MASTER-Net observations report
  68. GRB 240801A: Fermi GBM Final Real-time Localization
  69. GRB 240730C: AstroSat CZTI detection of a long burst
  70. GRB 240731A: Fermi GBM Final Localization
  71. GRB 240731A: AstroSat CZTI detection
  72. GRB 240730A: Osservatorio Astronomico Nastro Verde upper limit
  73. GRB240730A: BOOTES-5/JGT early optical upper limit
  74. Fermi Gamma-ray Burst Monitor trigger 744061103/240730818 is not a GRB
  75. Fermi GRB 240730B: Global MASTER-Net observations report
  76. GRB 240730B: Fermi GBM Final Real-time Localization
  77. Swift GRB 240730A: Global MASTER-Net observations report
  78. GRB 240730A: Swift-XRT refined Analysis
  79. GRB 240715A: Swift-XRT afterglow detection
  80. GRB 240730A: KAIT Optical Upper Limit
  81. GRB 240727C: GRBAlpha detection
  82. GRB 240730A: Swift/UVOT Upper Limits
  83. GRB 240730A: Enhanced Swift-XRT position
  84. GRB 240730A: Swift detection of a burst
  85. GRB 240727A: Swift-BAT refined analysis
  86. Fermi Gamma-ray Burst Monitor trigger 743953682/240729575 is not a GRB
  87. GRB 240727A: observations of optical counterpart.
  88. GRB 240727B: Swift-XRT observations
  89. Fermi GRB 240727A: Global MASTER-Net observations report
  90. GRB 240727A: Swift/UVOT detection
  91. Fermi Gamma-ray Burst Monitor trigger 743868421/240728588 is not a GRB
  92. GRB 240727A: Correction to time in GCN36960
  93. GRB 240727A: Osservatorio Astronomico Nastro Verde upper limit
  94. GRB 240727A: NOT optical observation
  95. GRB 240727A: JinShan optical upper limits
  96. GRB 240727A Bassano Bresciano Observatory upper limit
  97. GRB 240727D: Correction to the GRB name in GCN 36958
  98. GRB 240727A: Fermi GBM Final Real-time Localization
  99. GRB 240727C: AstroSat CZTI detection of a long burst
  100. GRB 240727A: Swift-XRT refined Analysis

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