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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"

28297 results found.

  1. GRB 241030A: AKO Optical Afterglow Detection
  2. GRB 241030A: Swift/UVOT Detection
  3. EP 241021a: further Swift-XRT observations and X-ray counterpart detection
  4. GRB 241026A: Swift-BAT refined analysis
  5. GRB 241030A: SVOM/C-GFT optical observations
  6. GRB 241026A: LBT optical observations
  7. EP241021a: Optical rebrightening observations with Mephisto
  8. GRB 241030A: Multiband optical detection with Mephisto
  9. GRB 241030A: SVOM/VT optical afterglow observations
  10. GRB 241030A : MITSuME Akeno optical afterglow detection
  11. GRB 241030A: Enhanced Swift-XRT position
  12. GRB 241029A: GROWTH-India Telescope optical follow up
  13. GRB 241030A: ULL-ASTRO-MASTER detection of a bright optical counterpart with the LCOGT 40-cm telescope at McDonald Observatory
  14. GRB 241030A: COLIBRÍ Detection of the Bright Optical Counterpart
  15. GRB 241030A: Swift detection of a burst with a bright optical counterpart
  16. GRB 241029A: SAO RAS optical observations
  17. GRB 241026A: SAO RAS optical observations
  18. EP241021a: SAO RAS observations of rebrightening
  19. GRB 241029A: GTC/OSIRIS+ spectroscopic redshift z=1.072
  20. MISTRAL@OHP photometric and spectroscopic observations of GRB 241029A
  21. GRB 241026A: Swift/UVOT Upper Limits
  22. GRB 241029A: Swift-XRT observations
  23. GRB 241029A: Fermi GBM Observation
  24. GRB 241029A: AKO Optical Afterglow Detection
  25. EP241021a: continued SOAR observations confirm optical rebrightening
  26. GRB 241029A: Xinglong-2.16m optical afterglow confirmation
  27. GRB 241029A: Mephisto observations
  28. EP 241026b: LBT possible optical counterpart (brightening source)
  29. GRB 241029A: TRT optical afterglow candidate detection
  30. GRB 241026A: TNOT optical counterpart detection
  31. GRB 241025A (EP241025a): Optical afterglow observations with the Tsinghua-Nanshan Optical Telescope
  32. GRB 241025A: further SAO RAS optical observations
  33. GRB 241026A: BTA and Zeiss-1000 optical observations
  34. GRB 241026A: SVOM/GRM observation
  35. EP241026B: GROWTH-India Telescope optical upper limit
  36. GRB 241025A: Swift/UVOT Detection
  37. GRB 241026A: GROWTH-India Telescope optical observations
  38. GRB 241026A Fermi GBM Analysis
  39. GRB 241026A: J-band observations with WINTER
  40. GRB 241025A: SAO RAS optical observations
  41. GRB 241026A: Las Cumbres optical detection
  42. GRB 241025A: Mondy optical observations
  43. EP241021a: SOAR observations of the optical counterpart
  44. EP241021a: further SAO RAS optical observations
  45. GRB 241026A: Swift-XRT refined Analysis
  46. EP 241026b: LBT optical observations
  47. GRB 241026A: Enhanced Swift-XRT position
  48. EP241026b: EP detection of a fast X-ray transient
  49. GRB 241026A: COLIBRÍ Detection of the Optical Counterpart
  50. GRB 241026A: SAO RAS observations of possible optical afterglow
  51. GRB 241026A: Swift detection of a burst
  52. GRB241025A: 1.3m DFOT optical afterglow detection
  53. EP241021a: optical follow-up observations with Xinglong Observatory
  54. GRB 241025A: GROWTH-India Telescope optical observations
  55. GRB 241025A: COLIBRÍ Detection of the Afterglow
  56. GRB 241025A: Swift-XRT refined Analysis
  57. GRB 241025C: Fermi GBM Detection
  58. GRB 241025A: Fermi GBM Observation
  59. IPN triangulation of GRB 241022A (short/hard)
  60. LIGO/Virgo/KAGRA S241009l: Upper limits from Swift/BAT-GUANO
  61. EP 241021a: Swift-XRT observations
  62. GRB 241025A : SVOM/VT optical afterglow observations
  63. EP241021a: Liverpool Telescope optical follow-up observations
  64. GRB 241025A: Enhanced Swift-XRT position
  65. GRB 241025A: DDOTI Afterglow detection
  66. GRB 241025A: TRT optical afterglow observation
  67. GRB 241025A: Swift detection of a burst with an optical counterpart
  68. EP241021a: GTC OSIRIS+ spectroscopy of the optical counterpart
  69. GRB 241001A: ATCA radio observations
  70. GRB 241010A: VIRT Optical Upper Limit
  71. EP241021a: SAO RAS optical observations
  72. EP241021a: KAIT optical observations
  73. EP241021a: 1.3m DFOT Optical observations
  74. EP241021a: GSP detects optical candidate counterpart
  75. EP241021a: Optical upper limits with Kinder observations
  76. EP241021a: TRT optical observations
  77. GRB 241018A: SVOM/C-GFT optical observations
  78. EP241021a: NOT likely optical counterpart
  79. EP EP241021a: Global MASTER-Net observations report
  80. GRB241017A: 1.3m DFOT optical upper limit
  81. GRB 241018A: 1.3m DFOT Optical upper limit
  82. EP241021a: GOTO optical upper limits
  83. EP241021a: EP detection of a fast X-ray transient
  84. IceCube-Cascade 241019A: Upper limits from a search for additional neutrino events in IceCube
  85. GRB 241018A/sb24101802: Mephisto optical upper limit
  86. GRB 241017A/sb24101702: Mephisto optical upper limit
  87. GRB 241018A: Mondy optical upper limit
  88. GRB 241018A: SVOM/VT further analysis and counterpart confirmed
  89. GRB 241018A: GROWTH-India telescope optical upper limit
  90. GRB241018A: XingLong Optical Upper Limit
  91. GRB 241018A: Swift-XRT observations
  92. GRB 241018A: REM optical/NIR upper limits
  93. GRB 241018A: NOT optical observations
  94. GRB 241018A: SVOM/VT follow-up and optical candidate
  95. GRB 241018A: LCO/0.4m optical upper limits
  96. GRB 241006A: VIRT Optical Upper Limit
  97. GRB 240727A: VIRT Optical Upper Limit
  98. GRB 241018A: X-ray afterglow candidate observed by MXT
  99. GRB 241017A: Swift-XRT observations
  100. GRB241017a: Liverpool Telescope observations of XRT uncatalogued sources

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