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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"

16119 results found.

  1. GRB 241030A / EP241030a: FTW Optical and NIR observations of the optical counterpart
  2. EP241026b: Liverpool Telescope optical follow-up
  3. GRB 241030A: SAO RAS optical observations
  4. GRB 241030B : GIT optical upper limits
  5. GRB 241030B: LCOGT Optical Upper Limits
  6. GRB 241029A: COLIBRI Detection of the Optical Counterpart
  7. GRB 241030B: Swift/UVOT Detection
  8. GRB 241029A: LCO optical detection
  9. GRB 241030B: GTC/OSIRIS+ tentative spectroscopic redshift z = 2.82
  10. GRB 241030B: SVOM/GRM observation
  11. GRB 241030B : MITSuME Akeno optical upper limits
  12. GRB 241030A: COLIBRI Continuing Detection of the Afterglow
  13. GRB 241030B: SVOM/VT optical afterglow observations
  14. GRB 241030B: COLIBRÍ Upper Limits on the Optical Counterpart
  15. GRB 241030B: BTA observations
  16. GRB 241029A: SVOM/VT optical afterglow observations
  17. GRB 241030A: detection of the bright optical counterpart in ATLAS forced photometry
  18. GRB 241030B: optical observations from the INAF Asiago Observatory
  19. EP241021a: Swift-UVOT detection
  20. GRB241030B: GRANDMA/TAROT Upper Limit
  21. GRB 241030B: SAO RAS optical observations
  22. GRB 241030B: AKO Optical Afterglow Detection
  23. GRB 241030B: Nanshan/HMT optical afterglow detection
  24. GRB 240912A: radio detection with the VLA
  25. GRB 241030A: AKO Optical Afterglow Detection
  26. GRB 241030A: Swift/UVOT Detection
  27. EP 241021a: further Swift-XRT observations and X-ray counterpart detection
  28. GRB 241030A: SVOM/GRM observation
  29. GRB 241030A: SVOM/C-GFT optical observations
  30. GRB 241026A: LBT optical observations
  31. EP241021a: Optical rebrightening observations with Mephisto
  32. EP241026b: EP-FXT follow-up observation
  33. GRB 241030A: Multiband optical detection with Mephisto
  34. GRB 241030A: SVOM/VT optical afterglow observations
  35. GRB 241025A: The discovery of a BdHN I from data of Swift, Fermi, SVOM and Einstein Probe telescopes
  36. GRB 241030A : MITSuME Akeno optical afterglow detection
  37. GRB 241029A: GROWTH-India Telescope optical follow up
  38. GRB 241030A: TRT optical observations
  39. GRB 241030A: Keck/LRIS spectroscopic redshift z = 1.411
  40. GRB 241030A: ULL-ASTRO-MASTER detection of a bright optical counterpart with the LCOGT 40-cm telescope at McDonald Observatory
  41. GRB 241030A: COLIBRÍ Detection of the Bright Optical Counterpart
  42. GRB 241030A: Swift detection of a burst with a bright optical counterpart
  43. GRB 241029A: SAO RAS optical observations
  44. GRB 241026A: SAO RAS optical observations
  45. EP241021a: SAO RAS observations of rebrightening
  46. EP241021a: ATCA radio observations
  47. GRB 241026A: Swift/UVOT Upper Limits
  48. GRB 241029A: Swift-XRT observations
  49. GRB 241029A: AKO Optical Afterglow Detection
  50. GRB 241029A: GOTO optical afterglow detection
  51. EP241021a: continued SOAR observations confirm optical rebrightening
  52. GRB 241029A: MASTER early optical counterpart detection
  53. GRB 241029A: Xinglong-2.16m optical afterglow confirmation
  54. GRB 241029A: Mephisto observations
  55. EP 241026b: LBT possible optical counterpart (brightening source)
  56. GRB 241029A: TRT optical afterglow candidate detection
  57. GRB 241029A: SVOM/GRM observation
  58. GRB 240821A: Keck/LRIS spectroscopic observations
  59. EP241021a: Gemini-South detection of optical rebrightening
  60. GRB 241026A: TNOT optical counterpart detection
  61. GRB 241025A (EP241025a): Optical afterglow observations with the Tsinghua-Nanshan Optical Telescope
  62. GRB 241026A: LBT redshift confirmation
  63. GRB 241025A: further SAO RAS optical observations
  64. GRB 241026A: BTA and Zeiss-1000 optical observations
  65. GRB 241026A: SVOM/GRM observation
  66. EP241026B: GROWTH-India Telescope optical upper limit
  67. GRB 241026A: GROWTH-India Telescope optical observations
  68. GRB 241026A: BTA redshift identification of z = 2.79
  69. GRB 241026A: J-band observations with WINTER
  70. GRB 241025A: SAO RAS optical observations
  71. GRB 241026A: Las Cumbres optical detection
  72. GRB 241025A: Mondy optical observations
  73. EP241021a: SOAR observations of the optical counterpart
  74. EP241021a: further SAO RAS optical observations
  75. EP 241026b: LBT optical observations
  76. EP241021a: e-MERLIN radio observation
  77. GRB 241026A: KAIT optical observations
  78. GRB 241026A: COLIBRÍ Detection of the Optical Counterpart
  79. GRB 241026A: SAO RAS observations of possible optical afterglow
  80. GRB241025A: 1.3m DFOT optical afterglow detection
  81. EP241021a: optical follow-up observations with Xinglong Observatory
  82. ​GRB 241025A: optical photometry from Konkoly
  83. GRB 241025A: GROWTH-India Telescope optical observations
  84. GRB 241025A: COLIBRÍ Detection of the Afterglow
  85. GRB 241025A: GRANDMA and Kilonova-Catcher optical afterglow detections and upperlimits
  86. EP241021a: Optical and NIR observations of counterpart with the Fraunhofer Telescope at Wendelstein Observatory
  87. EP241021a: Optical and NIR observations of counterpart with the Fraunhofer Telescope at Wendelstein Observatory
  88. EP241021a: optical follow-up observations with the Liverpool Telescope
  89. GRB 241025A : SVOM/VT optical afterglow observations
  90. EP241021a: Liverpool Telescope optical follow-up observations
  91. GRB 241001A: JWST spectroscopic identification of a supernova counterpart
  92. GRB 241025A: NOT spectroscopic redshift of z = 4.20
  93. GRB 241025A: TRT optical afterglow observation
  94. GRB 241025A: Swift detection of a burst with an optical counterpart
  95. EP241021a: GTC OSIRIS+ spectroscopy of the optical counterpart
  96. GRB 241001A: ATCA radio observations
  97. GRB 241010A: VIRT Optical Upper Limit
  98. EP241021a: VLT/FORS2 redshift z = 0.75
  99. EP241021a: SAO RAS optical observations
  100. EP241021a: KAIT optical observations

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