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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"

36408 results found.

  1. Fermi Gamma-ray Burst Monitor trigger 743953682/240729575 is not a GRB
  2. GRB 240727A: observations of optical counterpart.
  3. GRB 240727B: Swift-XRT observations
  4. Fermi GRB 240727A: Global MASTER-Net observations report
  5. GRB 240727A: Swift/UVOT detection
  6. Fermi Gamma-ray Burst Monitor trigger 743868421/240728588 is not a GRB
  7. GRB 240727A: Correction to time in GCN36960
  8. GRB 240727A: Osservatorio Astronomico Nastro Verde upper limit
  9. GRB 240727A: NOT optical observation
  10. GRB 240727A: JinShan optical upper limits
  11. GRB 240727A Bassano Bresciano Observatory upper limit
  12. GRB 240727D: Correction to the GRB name in GCN 36958
  13. GRB 240727A: Fermi GBM Final Real-time Localization
  14. GRB 240727C: AstroSat CZTI detection of a long burst
  15. GRB 240727A: Swift-XRT refined Analysis
  16. GRB 240720B: GRBAlpha detection
  17. GRB 240718A: GRBAlpha detection
  18. GRB 240710B: GRBAlpha detection
  19. GRB 240627A: GRBAlpha detection
  20. Fermi GRB 240726A: Global MASTER-Net observations report
  21. GRB 240727A: Enhanced Swift-XRT position
  22. GRB 240727B: Fermi GBM Observation
  23. GRB 240727B: Swift ToO observations
  24. GRB 240727B: Swift/BAT-GUANO arcminute localization of a long burst
  25. GRB 240726A: SVOM/GRM observation
  26. GRB 240727B: AstroSat CZTI detection
  27. GRB 240726B: AstroSat CZTI detection of a short burst
  28. GRB240727A: Skynet Optical Afterglow Observations
  29. GRB 240727A: TRT optical afterglow detection
  30. GRB 240727A: KAIT Optical Afterglow Candidate
  31. GRB 240727A: Swift detection of a burst
  32. GRB 240726A: AstroSat CZTI detection of a short burst
  33. IceCube-240725A: Upper limits from a search for additional neutrino events in IceCube
  34. GRB 240726A: Fermi GBM Final Real-time Localization
  35. Swift Trigger 1244778 is not a GRB
  36. GRB 240720A: Swift-BAT refined analysis
  37. IceCube-240721A: Upper limits from a search for additional neutrino events in IceCube
  38. LIGO/Virgo/KAGRA S240716b: Upper limits from Swift/BAT-GUANO
  39. LIGO/Virgo/KAGRA S240703ad: Upper limits from Swift/BAT-GUANO
  40. Fermi Gamma-ray Burst Monitor trigger 743271526/240721680 is not a GRB
  41. Fermi Gamma-ray Burst Monitor trigger 743243582/240721356 (GRB 240721A) is not a GRB
  42. GRB 240720B: SVOM/GRM observation
  43. GRB 240721A: Fermi GBM Final Real-time Localization
  44. GRB 240720B: AstroSat CZTI detection of a short burst
  45. Fermi GRB 240720A: Global MASTER-Net observations report
  46. GRB 240720A: AstroSat CZTI detection
  47. GRB 240720A: Fermi GBM observation
  48. GRB 240720A: Swift detection of a burst
  49. Konus-Wind detection of GRB 240718A
  50. GRB 240713A: SVOM/GRM observation
  51. Fermi GRB 240718A: Global MASTER-Net observations report
  52. GRB 240718A: Fermi GBM Observation
  53. GRB 240718A: Fermi-LAT Detection
  54. GRB 240718A: SVOM/GRM observation
  55. GRB 240718A: BALROG localization (Fermi Trigger 742976945 / GRB 240718270)
  56. GRB 240718A: Fermi GBM Final Real-time Localization
  57. GRB 240712A: Swift-BAT refined analysis
  58. GRB 240716A: GECAM-B detection of a long burst
  59. SVOM/GRM In-Flight Trigger of GRB 240716A
  60. GRB 240713A: 2.2m CAHA optical limit
  61. GRB 240715A: Swift/UVOT observations of the XRT sources.
  62. GRB 240715A: Swift-XRT observations
  63. GRB240713A: Swift/UVOT Upper LImits
  64. GRB 240715A: GECAM-C detection of a short burst
  65. Konus-Wind detection of GRB 240715A
  66. GRB 240713A: Swift-XRT observations
  67. GRB 240715A: TRT optical upper limit on one Swift/XRT candidate
  68. GRB 240712A: Swift-XRT refined Analysis
  69. SVOM/GRM In-Flight Trigger of GRB 240715A
  70. GRB 240713A: LAST optical upper limit
  71. GRB 240715A: Swift ToO observations
  72. Fermi GRB 240715A: Global MASTER-Net observations report
  73. GRB 240713A: optical upper limits from the INAF Asiago Observatory
  74. GRB 240715A: Fermi GBM Observation
  75. GRB 240712A ATCA radio observations
  76. GRB240715A: GRANDMA Optical Upper Limits
  77. IPN triangulation of GRB 240715A (short)
  78. GRB 240712A: Swift/UVOT Upper Limits
  79. GRB 240715A: Fermi GBM Final Real-time Localization
  80. GRB 240713A: Tiled Swift observations
  81. GRB 240713A: J-band upper limit from WINTER
  82. GRB 240713A: NOT optical upper limits on three EP/FXT candidates
  83. GRB 240713A: JinShan optical upper limits
  84. GRB 240713A: OHP/T120 optical upper limit
  85. GRB240713A: X-ray follow-up observation with EP-FXT
  86. GRB 240713B: AstroSat CZTI detection of a long burst
  87. Fermi Sub-threshold Observation of GRB240713A
  88. GRB240713A : The first probable GRB Located on-Board SVOM by ECLAIRs
  89. Fermi Gamma-ray Burst Monitor trigger 742413075/240711744 is not a GRB
  90. GRB 240712A: Swift detection of a burst
  91. GRB 240711A: Fermi GBM Final Real-time Localization
  92. EP240708a: KAIT optical upper limit
  93. Fermi GRB 240710A: Global MASTER-Net observations report
  94. GRB 240710A: Fermi GBM Final Real-time Localization
  95. EP240708a: SVOM/C-GFT optical upper limit
  96. Fermi Gamma-ray Burst Monitor trigger 741911057/240705933 is not a GRB
  97. GRB 240705A: Fermi GBM Final Real-time Localization
  98. Konus-Wind detection of GRB 240627A
  99. IPN triangulation of GRB 240628B (short)
  100. EP240703a: KAIT optical upper limit

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