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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"

16126 results found.

  1. GRB 241026A: SAO RAS optical observations
  2. GRB 241030A / EP241030a: GMG possible spectroscopic redshift at z ~ 1.4
  3. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits (duplicate submission of 38023)
  4. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits
  5. EP241021a: OHP/T193 optical observations
  6. GRB 241030A: Palomar 1-m telescope COSMOS optical observations
  7. GRB 241030B: Montarrenti Observatory optical upper limit
  8. GRB 241030A / EP241030a: FTW Optical and NIR observations of the optical counterpart
  9. EP241026b: Liverpool Telescope optical follow-up
  10. GRB 241030A: SAO RAS optical observations
  11. GRB 241030B : GIT optical upper limits
  12. GRB 241030B: LCOGT Optical Upper Limits
  13. GRB 241029A: COLIBRI Detection of the Optical Counterpart
  14. GRB 241030B: Swift/UVOT Detection
  15. GRB 241029A: LCO optical detection
  16. GRB 241030B: GTC/OSIRIS+ tentative spectroscopic redshift z = 2.82
  17. GRB 241030B: SVOM/GRM observation
  18. GRB 241030B : MITSuME Akeno optical upper limits
  19. GRB 241030A: COLIBRI Continuing Detection of the Afterglow
  20. GRB 241030B: SVOM/VT optical afterglow observations
  21. GRB 241030B: COLIBRÍ Upper Limits on the Optical Counterpart
  22. GRB 241030B: BTA observations
  23. GRB 241029A: SVOM/VT optical afterglow observations
  24. GRB 241030A: detection of the bright optical counterpart in ATLAS forced photometry
  25. GRB 241030B: optical observations from the INAF Asiago Observatory
  26. EP241021a: Swift-UVOT detection
  27. GRB241030B: GRANDMA/TAROT Upper Limit
  28. GRB 241030B: SAO RAS optical observations
  29. GRB 241030B: AKO Optical Afterglow Detection
  30. GRB 241030B: Nanshan/HMT optical afterglow detection
  31. GRB 240912A: radio detection with the VLA
  32. GRB 241030A: AKO Optical Afterglow Detection
  33. GRB 241030A: Swift/UVOT Detection
  34. EP 241021a: further Swift-XRT observations and X-ray counterpart detection
  35. GRB 241030A: SVOM/GRM observation
  36. GRB 241030A: SVOM/C-GFT optical observations
  37. GRB 241026A: LBT optical observations
  38. EP241021a: Optical rebrightening observations with Mephisto
  39. EP241026b: EP-FXT follow-up observation
  40. GRB 241030A: Multiband optical detection with Mephisto
  41. GRB 241030A: SVOM/VT optical afterglow observations
  42. GRB 241025A: The discovery of a BdHN I from data of Swift, Fermi, SVOM and Einstein Probe telescopes
  43. GRB 241030A : MITSuME Akeno optical afterglow detection
  44. GRB 241029A: GROWTH-India Telescope optical follow up
  45. GRB 241030A: TRT optical observations
  46. GRB 241030A: Keck/LRIS spectroscopic redshift z = 1.411
  47. GRB 241030A: ULL-ASTRO-MASTER detection of a bright optical counterpart with the LCOGT 40-cm telescope at McDonald Observatory
  48. GRB 241030A: COLIBRÍ Detection of the Bright Optical Counterpart
  49. GRB 241030A: Swift detection of a burst with a bright optical counterpart
  50. GRB 241029A: SAO RAS optical observations
  51. GRB 241026A: SAO RAS optical observations
  52. EP241021a: SAO RAS observations of rebrightening
  53. EP241021a: ATCA radio observations
  54. GRB 241026A: Swift/UVOT Upper Limits
  55. GRB 241029A: Swift-XRT observations
  56. GRB 241029A: AKO Optical Afterglow Detection
  57. GRB 241029A: GOTO optical afterglow detection
  58. EP241021a: continued SOAR observations confirm optical rebrightening
  59. GRB 241029A: MASTER early optical counterpart detection
  60. GRB 241029A: Xinglong-2.16m optical afterglow confirmation
  61. GRB 241029A: Mephisto observations
  62. EP 241026b: LBT possible optical counterpart (brightening source)
  63. GRB 241029A: TRT optical afterglow candidate detection
  64. GRB 241029A: SVOM/GRM observation
  65. GRB 240821A: Keck/LRIS spectroscopic observations
  66. EP241021a: Gemini-South detection of optical rebrightening
  67. GRB 241026A: TNOT optical counterpart detection
  68. GRB 241025A (EP241025a): Optical afterglow observations with the Tsinghua-Nanshan Optical Telescope
  69. GRB 241026A: LBT redshift confirmation
  70. GRB 241025A: further SAO RAS optical observations
  71. GRB 241026A: BTA and Zeiss-1000 optical observations
  72. GRB 241026A: SVOM/GRM observation
  73. EP241026B: GROWTH-India Telescope optical upper limit
  74. GRB 241026A: GROWTH-India Telescope optical observations
  75. GRB 241026A: BTA redshift identification of z = 2.79
  76. GRB 241026A: J-band observations with WINTER
  77. GRB 241025A: SAO RAS optical observations
  78. GRB 241026A: Las Cumbres optical detection
  79. GRB 241025A: Mondy optical observations
  80. EP241021a: SOAR observations of the optical counterpart
  81. EP241021a: further SAO RAS optical observations
  82. EP 241026b: LBT optical observations
  83. EP241021a: e-MERLIN radio observation
  84. GRB 241026A: KAIT optical observations
  85. GRB 241026A: COLIBRÍ Detection of the Optical Counterpart
  86. GRB 241026A: SAO RAS observations of possible optical afterglow
  87. GRB241025A: 1.3m DFOT optical afterglow detection
  88. EP241021a: optical follow-up observations with Xinglong Observatory
  89. ​GRB 241025A: optical photometry from Konkoly
  90. GRB 241025A: GROWTH-India Telescope optical observations
  91. GRB 241025A: COLIBRÍ Detection of the Afterglow
  92. GRB 241025A: GRANDMA and Kilonova-Catcher optical afterglow detections and upperlimits
  93. EP241021a: Optical and NIR observations of counterpart with the Fraunhofer Telescope at Wendelstein Observatory
  94. EP241021a: Optical and NIR observations of counterpart with the Fraunhofer Telescope at Wendelstein Observatory
  95. EP241021a: optical follow-up observations with the Liverpool Telescope
  96. GRB 241025A : SVOM/VT optical afterglow observations
  97. EP241021a: Liverpool Telescope optical follow-up observations
  98. GRB 241001A: JWST spectroscopic identification of a supernova counterpart
  99. GRB 241025A: NOT spectroscopic redshift of z = 4.20
  100. GRB 241025A: TRT optical afterglow observation

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