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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"

28291 results found.

  1. EP241021a: Optical rebrightening observations with Mephisto
  2. GRB 241030A: Multiband optical detection with Mephisto
  3. GRB 241030A: SVOM/VT optical afterglow observations
  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: ULL-ASTRO-MASTER detection of a bright optical counterpart with the LCOGT 40-cm telescope at McDonald Observatory
  8. GRB 241030A: COLIBRÍ Detection of the Bright Optical Counterpart
  9. GRB 241030A: Swift detection of a burst with a bright optical counterpart
  10. GRB 241029A: SAO RAS optical observations
  11. GRB 241026A: SAO RAS optical observations
  12. EP241021a: SAO RAS observations of rebrightening
  13. GRB 241029A: GTC/OSIRIS+ spectroscopic redshift z=1.072
  14. MISTRAL@OHP photometric and spectroscopic observations of GRB 241029A
  15. GRB 241026A: Swift/UVOT Upper Limits
  16. GRB 241029A: Swift-XRT observations
  17. GRB 241029A: Fermi GBM Observation
  18. GRB 241029A: AKO Optical Afterglow Detection
  19. EP241021a: continued SOAR observations confirm optical rebrightening
  20. GRB 241029A: Xinglong-2.16m optical afterglow confirmation
  21. GRB 241029A: Mephisto observations
  22. EP 241026b: LBT possible optical counterpart (brightening source)
  23. GRB 241029A: TRT optical afterglow candidate detection
  24. GRB 241026A: TNOT optical counterpart detection
  25. GRB 241025A (EP241025a): Optical afterglow observations with the Tsinghua-Nanshan Optical Telescope
  26. GRB 241025A: further SAO RAS optical observations
  27. GRB 241026A: BTA and Zeiss-1000 optical observations
  28. GRB 241026A: SVOM/GRM observation
  29. EP241026B: GROWTH-India Telescope optical upper limit
  30. GRB 241025A: Swift/UVOT Detection
  31. GRB 241026A: GROWTH-India Telescope optical observations
  32. GRB 241026A Fermi GBM Analysis
  33. GRB 241026A: J-band observations with WINTER
  34. GRB 241025A: SAO RAS optical observations
  35. GRB 241026A: Las Cumbres optical detection
  36. GRB 241025A: Mondy optical observations
  37. EP241021a: SOAR observations of the optical counterpart
  38. EP241021a: further SAO RAS optical observations
  39. GRB 241026A: Swift-XRT refined Analysis
  40. EP 241026b: LBT optical observations
  41. GRB 241026A: Enhanced Swift-XRT position
  42. EP241026b: EP detection of a fast X-ray transient
  43. GRB 241026A: COLIBRÍ Detection of the Optical Counterpart
  44. GRB 241026A: SAO RAS observations of possible optical afterglow
  45. GRB 241026A: Swift detection of a burst
  46. GRB241025A: 1.3m DFOT optical afterglow detection
  47. EP241021a: optical follow-up observations with Xinglong Observatory
  48. GRB 241025A: GROWTH-India Telescope optical observations
  49. GRB 241025A: COLIBRÍ Detection of the Afterglow
  50. GRB 241025A: Swift-XRT refined Analysis
  51. GRB 241025C: Fermi GBM Detection
  52. GRB 241025A: Fermi GBM Observation
  53. IPN triangulation of GRB 241022A (short/hard)
  54. LIGO/Virgo/KAGRA S241009l: Upper limits from Swift/BAT-GUANO
  55. EP 241021a: Swift-XRT observations
  56. GRB 241025A : SVOM/VT optical afterglow observations
  57. EP241021a: Liverpool Telescope optical follow-up observations
  58. GRB 241025A: Enhanced Swift-XRT position
  59. GRB 241025A: DDOTI Afterglow detection
  60. GRB 241025A: TRT optical afterglow observation
  61. GRB 241025A: Swift detection of a burst with an optical counterpart
  62. EP241021a: GTC OSIRIS+ spectroscopy of the optical counterpart
  63. GRB 241001A: ATCA radio observations
  64. GRB 241010A: VIRT Optical Upper Limit
  65. EP241021a: SAO RAS optical observations
  66. EP241021a: KAIT optical observations
  67. EP241021a: 1.3m DFOT Optical observations
  68. EP241021a: GSP detects optical candidate counterpart
  69. EP241021a: Optical upper limits with Kinder observations
  70. EP241021a: TRT optical observations
  71. GRB 241018A: SVOM/C-GFT optical observations
  72. EP241021a: NOT likely optical counterpart
  73. EP EP241021a: Global MASTER-Net observations report
  74. GRB241017A: 1.3m DFOT optical upper limit
  75. GRB 241018A: 1.3m DFOT Optical upper limit
  76. EP241021a: GOTO optical upper limits
  77. EP241021a: EP detection of a fast X-ray transient
  78. IceCube-Cascade 241019A: Upper limits from a search for additional neutrino events in IceCube
  79. GRB 241018A/sb24101802: Mephisto optical upper limit
  80. GRB 241017A/sb24101702: Mephisto optical upper limit
  81. GRB 241018A: Mondy optical upper limit
  82. GRB 241018A: SVOM/VT further analysis and counterpart confirmed
  83. GRB 241018A: GROWTH-India telescope optical upper limit
  84. GRB241018A: XingLong Optical Upper Limit
  85. GRB 241018A: Swift-XRT observations
  86. GRB 241018A: REM optical/NIR upper limits
  87. GRB 241018A: NOT optical observations
  88. GRB 241018A: SVOM/VT follow-up and optical candidate
  89. GRB 241018A: LCO/0.4m optical upper limits
  90. GRB 241006A: VIRT Optical Upper Limit
  91. GRB 240727A: VIRT Optical Upper Limit
  92. GRB 241018A: X-ray afterglow candidate observed by MXT
  93. GRB 241017A: Swift-XRT observations
  94. GRB241017a: Liverpool Telescope observations of XRT uncatalogued sources
  95. GRB 241001A: EP-FXT afterglow detection
  96. GRB 241017A: GROWTH-India Telescope optical upper limit
  97. GRB241017A: TOO Observations by SVOM/MXT
  98. GRB 241016B: Swift/BAT-GUANO localization skymap of a short burst
  99. GRB 241017A: J-band upper limit from WINTER
  100. GRB 241016B: SVOM/GRM observation

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