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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"

36298 results found.

  1. Fermi Gamma-ray Burst Monitor trigger 744061103/240730818 is not a GRB
  2. Fermi GRB 240730B: Global MASTER-Net observations report
  3. GRB 240730B: Fermi GBM Final Real-time Localization
  4. Swift GRB 240730A: Global MASTER-Net observations report
  5. GRB 240730A: Swift-XRT refined Analysis
  6. GRB 240715A: Swift-XRT afterglow detection
  7. GRB 240730A: KAIT Optical Upper Limit
  8. GRB 240727C: GRBAlpha detection
  9. GRB 240730A: Swift/UVOT Upper Limits
  10. GRB 240730A: Enhanced Swift-XRT position
  11. GRB 240730A: Swift detection of a burst
  12. GRB 240727A: Swift-BAT refined analysis
  13. Fermi Gamma-ray Burst Monitor trigger 743953682/240729575 is not a GRB
  14. GRB 240727A: observations of optical counterpart.
  15. GRB 240727B: Swift-XRT observations
  16. Fermi GRB 240727A: Global MASTER-Net observations report
  17. GRB 240727A: Swift/UVOT detection
  18. Fermi Gamma-ray Burst Monitor trigger 743868421/240728588 is not a GRB
  19. GRB 240727A: Correction to time in GCN36960
  20. GRB 240727A: Osservatorio Astronomico Nastro Verde upper limit
  21. GRB 240727A: NOT optical observation
  22. GRB 240727A: JinShan optical upper limits
  23. GRB 240727A Bassano Bresciano Observatory upper limit
  24. GRB 240727D: Correction to the GRB name in GCN 36958
  25. GRB 240727A: Fermi GBM Final Real-time Localization
  26. GRB 240727C: AstroSat CZTI detection of a long burst
  27. GRB 240727A: Swift-XRT refined Analysis
  28. GRB 240720B: GRBAlpha detection
  29. GRB 240718A: GRBAlpha detection
  30. GRB 240710B: GRBAlpha detection
  31. GRB 240627A: GRBAlpha detection
  32. Fermi GRB 240726A: Global MASTER-Net observations report
  33. GRB 240727A: Enhanced Swift-XRT position
  34. GRB 240727B: Fermi GBM Observation
  35. GRB 240727B: Swift ToO observations
  36. GRB 240727B: Swift/BAT-GUANO arcminute localization of a long burst
  37. GRB 240726A: SVOM/GRM observation
  38. GRB 240727B: AstroSat CZTI detection
  39. GRB 240726B: AstroSat CZTI detection of a short burst
  40. GRB240727A: Skynet Optical Afterglow Observations
  41. GRB 240727A: TRT optical afterglow detection
  42. GRB 240727A: KAIT Optical Afterglow Candidate
  43. GRB 240727A: Swift detection of a burst
  44. GRB 240726A: AstroSat CZTI detection of a short burst
  45. GRB 240726A: Fermi GBM Final Real-time Localization
  46. Swift Trigger 1244778 is not a GRB
  47. GRB 240720A: Swift-BAT refined analysis
  48. LIGO/Virgo/KAGRA S240716b: Upper limits from Swift/BAT-GUANO
  49. LIGO/Virgo/KAGRA S240703ad: Upper limits from Swift/BAT-GUANO
  50. Fermi Gamma-ray Burst Monitor trigger 743271526/240721680 is not a GRB
  51. Fermi Gamma-ray Burst Monitor trigger 743243582/240721356 (GRB 240721A) is not a GRB
  52. GRB 240720B: SVOM/GRM observation
  53. GRB 240721A: Fermi GBM Final Real-time Localization
  54. GRB 240720B: AstroSat CZTI detection of a short burst
  55. Fermi GRB 240720A: Global MASTER-Net observations report
  56. GRB 240720A: AstroSat CZTI detection
  57. GRB 240720A: Fermi GBM observation
  58. GRB 240720A: Swift detection of a burst
  59. Konus-Wind detection of GRB 240718A
  60. GRB 240713A: SVOM/GRM observation
  61. Fermi GRB 240718A: Global MASTER-Net observations report
  62. GRB 240718A: Fermi GBM Observation
  63. GRB 240718A: Fermi-LAT Detection
  64. GRB 240718A: SVOM/GRM observation
  65. GRB 240718A: BALROG localization (Fermi Trigger 742976945 / GRB 240718270)
  66. GRB 240718A: Fermi GBM Final Real-time Localization
  67. GRB 240712A: Swift-BAT refined analysis
  68. GRB 240716A: GECAM-B detection of a long burst
  69. SVOM/GRM In-Flight Trigger of GRB 240716A
  70. GRB 240713A: 2.2m CAHA optical limit
  71. GRB 240715A: Swift/UVOT observations of the XRT sources.
  72. GRB 240715A: Swift-XRT observations
  73. GRB240713A: Swift/UVOT Upper LImits
  74. GRB 240715A: GECAM-C detection of a short burst
  75. Konus-Wind detection of GRB 240715A
  76. GRB 240713A: Swift-XRT observations
  77. GRB 240715A: TRT optical upper limit on one Swift/XRT candidate
  78. GRB 240712A: Swift-XRT refined Analysis
  79. SVOM/GRM In-Flight Trigger of GRB 240715A
  80. GRB 240713A: LAST optical upper limit
  81. GRB 240715A: Swift ToO observations
  82. Fermi GRB 240715A: Global MASTER-Net observations report
  83. GRB 240713A: optical upper limits from the INAF Asiago Observatory
  84. GRB 240715A: Fermi GBM Observation
  85. GRB 240712A ATCA radio observations
  86. GRB240715A: GRANDMA Optical Upper Limits
  87. IPN triangulation of GRB 240715A (short)
  88. GRB 240712A: Swift/UVOT Upper Limits
  89. GRB 240715A: Fermi GBM Final Real-time Localization
  90. GRB 240713A: Tiled Swift observations
  91. GRB 240713A: J-band upper limit from WINTER
  92. GRB 240713A: NOT optical upper limits on three EP/FXT candidates
  93. GRB 240713A: JinShan optical upper limits
  94. GRB 240713A: OHP/T120 optical upper limit
  95. GRB240713A: X-ray follow-up observation with EP-FXT
  96. GRB 240713B: AstroSat CZTI detection of a long burst
  97. Fermi Sub-threshold Observation of GRB240713A
  98. GRB240713A : The first probable GRB Located on-Board SVOM by ECLAIRs
  99. Fermi Gamma-ray Burst Monitor trigger 742413075/240711744 is not a GRB
  100. GRB 240712A: Swift detection of a burst

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