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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.

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

45736 results found.

  1. GRB 241030A: Multiband optical detection with Mephisto
  2. GRB 241030A: SVOM/VT optical afterglow observations
  3. GRB 241025A: The discovery of a BdHN I from data of Swift, Fermi, SVOM and Einstein Probe telescopes
  4. GRB 241030A : MITSuME Akeno optical afterglow detection
  5. GRB 241030A: Enhanced Swift-XRT position
  6. GRB 241029A: GROWTH-India Telescope optical follow up
  7. GRB 241030A: TRT optical observations
  8. GRB 241030A: Keck/LRIS spectroscopic redshift z = 1.411
  9. GRB 241030A: ULL-ASTRO-MASTER detection of a bright optical counterpart with the LCOGT 40-cm telescope at McDonald Observatory
  10. GRB 241030A: COLIBRÍ Detection of the Bright Optical Counterpart
  11. GRB 241030A: Swift detection of a burst with a bright optical counterpart
  12. GRB 241030A: Fermi GBM Final Real-time Localization
  13. GRB 241029A: SAO RAS optical observations
  14. GRB 241026A: SAO RAS optical observations
  15. EP240919a / GRB 240919A: ATCA Detection of Radio Counterpart
  16. EP241021a: SAO RAS observations of rebrightening
  17. GRB 241029A: GTC/OSIRIS+ spectroscopic redshift z=1.072
  18. EP241021a: ATCA radio observations
  19. MISTRAL@OHP photometric and spectroscopic observations of GRB 241029A
  20. GRB 241026A: Swift/UVOT Upper Limits
  21. GRB 241029A: Swift-XRT observations
  22. GRB 241029A: Fermi GBM Observation
  23. GRB 241029A: AKO Optical Afterglow Detection
  24. GRB 241029A: GOTO optical afterglow detection
  25. EP241021a: continued SOAR observations confirm optical rebrightening
  26. GRB 241029A: MASTER early optical counterpart detection
  27. GRB 241029A: Xinglong-2.16m optical afterglow confirmation
  28. GRB 241029A: Mephisto observations
  29. EP 241026b: LBT possible optical counterpart (brightening source)
  30. GRB 241029A: TRT optical afterglow candidate detection
  31. GRB 241029A: Swift ToO observations
  32. GRB 241029A: SVOM/GRM observation
  33. GRB 241029A : Detection and localization of a bright long GRB by SVOM/ECLAIRs
  34. Fermi trigger No 751861204: Global MASTER-Net observations report
  35. GRB 241029A: Fermi GBM Final Real-time Localization
  36. GRB 240821A: Keck/LRIS spectroscopic observations
  37. EP241021a: Gemini-South detection of optical rebrightening
  38. GRB 241026A: the 100th GRB detected by GRBAlpha
  39. GRB 241026A: TNOT optical counterpart detection
  40. Konus-Wind detection of GRB 241025A
  41. GRB 241025A (EP241025a): Optical afterglow observations with the Tsinghua-Nanshan Optical Telescope
  42. GRB 241026A: LBT redshift confirmation
  43. GRB 241026A: GECAM detection
  44. GRB 241025A: further SAO RAS optical observations
  45. GRB 241026A: BTA and Zeiss-1000 optical observations
  46. GRB 241026A: SVOM/GRM observation
  47. EP241026B: GROWTH-India Telescope optical upper limit
  48. GRB 241025A: Swift/UVOT Detection
  49. GRB 241026A: GROWTH-India Telescope optical observations
  50. GRB 241026A Fermi GBM Analysis
  51. GRB 241026A: BTA redshift identification of z = 2.79
  52. GRB 241026A: J-band observations with WINTER
  53. GRB 241025A: SAO RAS optical observations
  54. GRB 241026A: Las Cumbres optical detection
  55. GRB 241025A: Mondy optical observations
  56. EP241021a: SOAR observations of the optical counterpart
  57. EP241021a: further SAO RAS optical observations
  58. EP241026a (GRB 241026A): EP on-board trigger and follow-up observation
  59. GRB 241026A: Swift-XRT refined Analysis
  60. EP 241026b: LBT optical observations
  61. EP241021a: e-MERLIN radio observation
  62. EP EP241026b: Global MASTER-Net observations report
  63. GRB 241026A: Enhanced Swift-XRT position
  64. GRB 241026A: KAIT optical observations
  65. EP241026b: EP detection of a fast X-ray transient
  66. Fermi trigger No 751616906: Global MASTER-Net observations report
  67. GRB 241026A: COLIBRÍ Detection of the Optical Counterpart
  68. GRB 241026A: SAO RAS observations of possible optical afterglow
  69. Fermi GRB 241026A: Global MASTER-Net observations report
  70. GRB 241026A: Prompt enhanced Swift-XRT position
  71. GRB 241026A: Swift detection of a burst
  72. Swift GRB241026.95: Global MASTER-Net observations report
  73. GRB 241026A: Fermi GBM Final Real-time Localization
  74. GRB241025A: 1.3m DFOT optical afterglow detection
  75. EP241021a: optical follow-up observations with Xinglong Observatory
  76. ​GRB 241025A: optical photometry from Konkoly
  77. GRB 241025A: GROWTH-India Telescope optical observations
  78. GRB 241025A: COLIBRÍ Detection of the Afterglow
  79. GRB 241025A: Swift-XRT refined Analysis
  80. GRB 241025C: Fermi GBM Detection
  81. GRB 241025A: Fermi GBM Observation
  82. IPN triangulation of GRB 241022A (short/hard)
  83. LIGO/Virgo/KAGRA S241009l: Upper limits from Swift/BAT-GUANO
  84. GRB 241025C: Fermi GBM Final Localization
  85. GRB 241025A: GRANDMA and Kilonova-Catcher optical afterglow detections and upperlimits
  86. GRB 241025B: Fermi GBM Final Localization
  87. Fermi trigger No 751563375: Global MASTER-Net observations report
  88. Fermi trigger No 751554401: Global MASTER-Net observations report
  89. EP241021a: Optical and NIR observations of counterpart with the Fraunhofer Telescope at Wendelstein Observatory
  90. EP241021a: Optical and NIR observations of counterpart with the Fraunhofer Telescope at Wendelstein Observatory
  91. EP 241021a: Swift-XRT observations
  92. EP241021a: optical follow-up observations with the Liverpool Telescope
  93. Fermi GRB 241025A: Global MASTER-Net observations report
  94. Swift GRB 241025A: Global MASTER-Net observations report
  95. EP241025a (GRB 241025A): EP observations update
  96. GRB 241025A : SVOM/VT optical afterglow observations
  97. EP 241021A: Swift ToO observations
  98. EP241021a: Liverpool Telescope optical follow-up observations
  99. GRB 241025A: Enhanced Swift-XRT position
  100. GRB 241001A: JWST spectroscopic identification of a supernova counterpart

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