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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').
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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

37331 results found.

  1. GRB 241030A: Fermi GBM Final Real-time Localization
  2. GRB 241029A: SAO RAS optical observations
  3. GRB 241026A: SAO RAS optical observations
  4. EP240919a / GRB 240919A: ATCA Detection of Radio Counterpart
  5. EP241021a: SAO RAS observations of rebrightening
  6. GRB 241029A: GTC/OSIRIS+ spectroscopic redshift z=1.072
  7. MISTRAL@OHP photometric and spectroscopic observations of GRB 241029A
  8. GRB 241026A: Swift/UVOT Upper Limits
  9. GRB 241029A: Swift-XRT observations
  10. GRB 241029A: Fermi GBM Observation
  11. GRB 241029A: AKO Optical Afterglow Detection
  12. GRB 241029A: GOTO optical afterglow detection
  13. GRB 241029A: MASTER early optical counterpart detection
  14. GRB 241029A: Xinglong-2.16m optical afterglow confirmation
  15. GRB 241029A: Mephisto observations
  16. EP 241026b: LBT possible optical counterpart (brightening source)
  17. GRB 241029A: TRT optical afterglow candidate detection
  18. GRB 241029A: Swift ToO observations
  19. GRB 241029A: SVOM/GRM observation
  20. GRB 241029A : Detection and localization of a bright long GRB by SVOM/ECLAIRs
  21. GRB 241029A: Fermi GBM Final Real-time Localization
  22. GRB 240821A: Keck/LRIS spectroscopic observations
  23. GRB 241026A: the 100th GRB detected by GRBAlpha
  24. GRB 241026A: TNOT optical counterpart detection
  25. Konus-Wind detection of GRB 241025A
  26. GRB 241025A (EP241025a): Optical afterglow observations with the Tsinghua-Nanshan Optical Telescope
  27. GRB 241026A: LBT redshift confirmation
  28. GRB 241026A: GECAM detection
  29. GRB 241025A: further SAO RAS optical observations
  30. GRB 241026A: BTA and Zeiss-1000 optical observations
  31. GRB 241026A: SVOM/GRM observation
  32. GRB 241025A: Swift/UVOT Detection
  33. GRB 241026A: GROWTH-India Telescope optical observations
  34. GRB 241026A Fermi GBM Analysis
  35. GRB 241026A: BTA redshift identification of z = 2.79
  36. GRB 241026A: J-band observations with WINTER
  37. GRB 241025A: SAO RAS optical observations
  38. GRB 241026A: Las Cumbres optical detection
  39. GRB 241025A: Mondy optical observations
  40. EP241021a: further SAO RAS optical observations
  41. EP241026a (GRB 241026A): EP on-board trigger and follow-up observation
  42. GRB 241026A: Swift-XRT refined Analysis
  43. GRB 241026A: Enhanced Swift-XRT position
  44. GRB 241026A: KAIT optical observations
  45. GRB 241026A: COLIBRÍ Detection of the Optical Counterpart
  46. GRB 241026A: SAO RAS observations of possible optical afterglow
  47. Fermi GRB 241026A: Global MASTER-Net observations report
  48. GRB 241026A: Prompt enhanced Swift-XRT position
  49. GRB 241026A: Swift detection of a burst
  50. GRB 241026A: Fermi GBM Final Real-time Localization
  51. GRB241025A: 1.3m DFOT optical afterglow detection
  52. ​GRB 241025A: optical photometry from Konkoly
  53. GRB 241025A: GROWTH-India Telescope optical observations
  54. GRB 241025A: COLIBRÍ Detection of the Afterglow
  55. GRB 241025A: Swift-XRT refined Analysis
  56. GRB 241025C: Fermi GBM Detection
  57. GRB 241025A: Fermi GBM Observation
  58. IPN triangulation of GRB 241022A (short/hard)
  59. LIGO/Virgo/KAGRA S241009l: Upper limits from Swift/BAT-GUANO
  60. GRB 241025C: Fermi GBM Final Localization
  61. GRB 241025A: GRANDMA and Kilonova-Catcher optical afterglow detections and upperlimits
  62. GRB 241025B: Fermi GBM Final Localization
  63. EP241021a: Optical and NIR observations of counterpart with the Fraunhofer Telescope at Wendelstein Observatory
  64. EP241021a: Optical and NIR observations of counterpart with the Fraunhofer Telescope at Wendelstein Observatory
  65. EP 241021a: Swift-XRT observations
  66. EP241021a: optical follow-up observations with the Liverpool Telescope
  67. Fermi GRB 241025A: Global MASTER-Net observations report
  68. Swift GRB 241025A: Global MASTER-Net observations report
  69. EP241025a (GRB 241025A): EP observations update
  70. GRB 241025A : SVOM/VT optical afterglow observations
  71. EP 241021A: Swift ToO observations
  72. GRB 241025A: Enhanced Swift-XRT position
  73. GRB 241001A: JWST spectroscopic identification of a supernova counterpart
  74. GRB 241025A: NOT spectroscopic redshift of z = 4.20
  75. GRB 241025A: DDOTI Afterglow detection
  76. EP241025a (GRB 241025A): EP on-board trigger and autonomous follow-up observation
  77. GRB 241025A: SVOM/GRM observation
  78. GRB 241025A: TRT optical afterglow observation
  79. Fermi GRB 241024B: Global MASTER-Net observations report
  80. GRB 241025A: Fermi GBM Final Real-time Localization
  81. GRB 241025A: Swift detection of a burst with an optical counterpart
  82. GRB 241001A: ATCA radio observations
  83. GRB 241024B: Fermi GBM Final Localization
  84. EP241021a: No Detection in Fermi-GBM Observation
  85. GRB 241010A: VIRT Optical Upper Limit
  86. GRB 241024A: Fermi GBM Final Localisation
  87. EP241021a: VLT/FORS2 redshift z = 0.75
  88. EP241021a: SAO RAS optical observations
  89. EP241021a: KAIT optical observations
  90. IPN triangulation of GRB 241021A (long)
  91. EP241021a: Optical upper limits with Kinder observations
  92. GRB 241018A: SVOM/C-GFT optical observations
  93. GRB241017A: 1.3m DFOT optical upper limit
  94. GRB 241018A: 1.3m DFOT Optical upper limit
  95. GRB 241018A: EP-FXT afterglow detection
  96. Konus-Wind detection of GRB 241018A
  97. GRB 241018A: SVOM/GRM observation
  98. GRB 241018A/sb24101802: Mephisto optical upper limit
  99. GRB 241017A/sb24101702: Mephisto optical upper limit
  100. GRB 241018A: BOOTES-4/MET optical upper limit

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