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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. GRB 240720B: GRBAlpha detection
  2. GRB 240718A: GRBAlpha detection
  3. GRB 240710B: GRBAlpha detection
  4. GRB 240627A: GRBAlpha detection
  5. Fermi GRB 240726A: Global MASTER-Net observations report
  6. GRB 240727A: Enhanced Swift-XRT position
  7. GRB 240727B: Fermi GBM Observation
  8. GRB 240727B: Swift ToO observations
  9. GRB 240727B: Swift/BAT-GUANO arcminute localization of a long burst
  10. GRB 240726A: SVOM/GRM observation
  11. GRB 240727B: AstroSat CZTI detection
  12. GRB 240726B: AstroSat CZTI detection of a short burst
  13. GRB240727A: Skynet Optical Afterglow Observations
  14. GRB 240727A: TRT optical afterglow detection
  15. GRB 240727A: KAIT Optical Afterglow Candidate
  16. GRB 240727A: Swift detection of a burst
  17. GRB 240726A: AstroSat CZTI detection of a short burst
  18. GRB 240726A: Fermi GBM Final Real-time Localization
  19. Swift Trigger 1244778 is not a GRB
  20. GRB 240720A: Swift-BAT refined analysis
  21. LIGO/Virgo/KAGRA S240716b: Upper limits from Swift/BAT-GUANO
  22. LIGO/Virgo/KAGRA S240703ad: Upper limits from Swift/BAT-GUANO
  23. Fermi Gamma-ray Burst Monitor trigger 743271526/240721680 is not a GRB
  24. Fermi Gamma-ray Burst Monitor trigger 743243582/240721356 (GRB 240721A) is not a GRB
  25. GRB 240720B: SVOM/GRM observation
  26. GRB 240721A: Fermi GBM Final Real-time Localization
  27. GRB 240720B: AstroSat CZTI detection of a short burst
  28. Fermi GRB 240720A: Global MASTER-Net observations report
  29. GRB 240720A: AstroSat CZTI detection
  30. GRB 240720A: Fermi GBM observation
  31. GRB 240720A: Swift detection of a burst
  32. Konus-Wind detection of GRB 240718A
  33. GRB 240713A: SVOM/GRM observation
  34. Fermi GRB 240718A: Global MASTER-Net observations report
  35. GRB 240718A: Fermi GBM Observation
  36. GRB 240718A: Fermi-LAT Detection
  37. GRB 240718A: SVOM/GRM observation
  38. GRB 240718A: BALROG localization (Fermi Trigger 742976945 / GRB 240718270)
  39. GRB 240718A: Fermi GBM Final Real-time Localization
  40. GRB 240712A: Swift-BAT refined analysis
  41. GRB 240716A: GECAM-B detection of a long burst
  42. SVOM/GRM In-Flight Trigger of GRB 240716A
  43. GRB 240713A: 2.2m CAHA optical limit
  44. GRB 240715A: Swift/UVOT observations of the XRT sources.
  45. GRB 240715A: Swift-XRT observations
  46. GRB240713A: Swift/UVOT Upper LImits
  47. GRB 240715A: GECAM-C detection of a short burst
  48. Konus-Wind detection of GRB 240715A
  49. GRB 240713A: Swift-XRT observations
  50. GRB 240715A: TRT optical upper limit on one Swift/XRT candidate
  51. GRB 240712A: Swift-XRT refined Analysis
  52. SVOM/GRM In-Flight Trigger of GRB 240715A
  53. GRB 240713A: LAST optical upper limit
  54. GRB 240715A: Swift ToO observations
  55. Fermi GRB 240715A: Global MASTER-Net observations report
  56. GRB 240713A: optical upper limits from the INAF Asiago Observatory
  57. GRB 240715A: Fermi GBM Observation
  58. GRB 240712A ATCA radio observations
  59. GRB240715A: GRANDMA Optical Upper Limits
  60. IPN triangulation of GRB 240715A (short)
  61. GRB 240712A: Swift/UVOT Upper Limits
  62. GRB 240715A: Fermi GBM Final Real-time Localization
  63. GRB 240713A: Tiled Swift observations
  64. GRB 240713A: J-band upper limit from WINTER
  65. GRB 240713A: NOT optical upper limits on three EP/FXT candidates
  66. GRB 240713A: JinShan optical upper limits
  67. GRB 240713A: OHP/T120 optical upper limit
  68. GRB240713A: X-ray follow-up observation with EP-FXT
  69. GRB 240713B: AstroSat CZTI detection of a long burst
  70. Fermi Sub-threshold Observation of GRB240713A
  71. GRB240713A : The first probable GRB Located on-Board SVOM by ECLAIRs
  72. Fermi Gamma-ray Burst Monitor trigger 742413075/240711744 is not a GRB
  73. GRB 240712A: Swift detection of a burst
  74. GRB 240711A: Fermi GBM Final Real-time Localization
  75. EP240708a: KAIT optical upper limit
  76. Fermi GRB 240710A: Global MASTER-Net observations report
  77. GRB 240710A: Fermi GBM Final Real-time Localization
  78. EP240708a: SVOM/C-GFT optical upper limit
  79. Fermi Gamma-ray Burst Monitor trigger 741911057/240705933 is not a GRB
  80. GRB 240705A: Fermi GBM Final Real-time Localization
  81. Konus-Wind detection of GRB 240627A
  82. IPN triangulation of GRB 240628B (short)
  83. EP240703a: KAIT optical upper limit
  84. EP240703a: BTA observations
  85. EP240703a/GRB 240703A: TRT optical candidate likely not real
  86. EP240703a/GRB 240703A: TRT and JinShan decaying optical afterglow candidate
  87. IPN triangulation of GRB 240627A
  88. GRB 240619A: Host galaxy redshift from VLT/X-shooter
  89. The first three GRBs detected by SVOM: X-ray Upper Limits from EP-WXT
  90. Konus-Wind detection of GRB 240703A (a counterpart of EP240703a)
  91. The first three GRBs detected by SVOM: GRB 240627B, GRB 240629A and GRB 240702A
  92. GRB 240702A: BALROG localization (Fermi Trigger / GRB 240702885)
  93. Fermi GRB 240702A: Global MASTER-Net observations report
  94. GRB 240702A: Fermi GBM Final Real-time Localization
  95. LIGO/Virgo/KAGRA S240627by: Upper limits from Swift/BAT-GUANO
  96. Fermi Gamma-ray Burst Monitor trigger 741448122/240630575 is not a GRB
  97. GRB 240627A: CALET Gamma-Ray Burst Monitor detection
  98. LIGO/Virgo/KAGRA S240629by: Upper limits from Fermi-GBM Observations
  99. Fermi GRB 240629A: Global MASTER-Net observations report
  100. Fermi Gamma-ray Burst Monitor trigger 741362867/240629589 is not a GRB

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