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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"

36409 results found.

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

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