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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"

19701 results found.

  1. GRB 241026A: SAO RAS optical observations
  2. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits
  3. EP241021a: OHP/T193 optical observations
  4. GRB 241030A: Palomar 1-m telescope COSMOS optical observations
  5. GRB 241030B: Montarrenti Observatory optical upper limit
  6. EP241026b: Liverpool Telescope optical follow-up
  7. GRB 241030A: SAO RAS optical observations
  8. EP241021a: AMI-LA radio detection
  9. GRB 241030B : GIT optical upper limits
  10. GRB 241030B: LCOGT Optical Upper Limits
  11. GRB 241029A: COLIBRI Detection of the Optical Counterpart
  12. GRB 241030B: Swift/UVOT Detection
  13. GRB 241029A: LCO optical detection
  14. GRB 241030B: GTC/OSIRIS+ tentative spectroscopic redshift z = 2.82
  15. GRB 241030B : MITSuME Akeno optical upper limits
  16. GRB 241030A: COLIBRI Continuing Detection of the Afterglow
  17. GRB 241030B: SVOM/VT optical afterglow observations
  18. GRB 241030B: COLIBRÍ Upper Limits on the Optical Counterpart
  19. EP241030a: EP detection of GRB 241030A X-ray Afterglow
  20. GRB 241030B: BTA observations
  21. GRB 241029A: SVOM/VT optical afterglow observations
  22. GRB 241030B: Enhanced Swift-XRT position
  23. GRB241030B: GRANDMA/TAROT Upper Limit
  24. GRB 241030B: SAO RAS optical observations
  25. GRB 241030B: AKO Optical Afterglow Detection
  26. GRB 241030B: Nanshan/HMT optical afterglow detection
  27. GRB 241030B: SVOM/ECLAIRs detection of a burst
  28. GRB 241030B: Swift detection of a burst
  29. GRB 240912A: radio detection with the VLA
  30. GRB 241030A: AKO Optical Afterglow Detection
  31. GRB 241030A: Swift/UVOT Detection
  32. GRB 241030A: SVOM/C-GFT optical observations
  33. GRB 241026A: LBT optical observations
  34. EP241021a: Optical rebrightening observations with Mephisto
  35. GRB 241030A: Multiband optical detection with Mephisto
  36. GRB 241030A: SVOM/VT optical afterglow observations
  37. GRB 241030A : MITSuME Akeno optical afterglow detection
  38. GRB 241030A: Enhanced Swift-XRT position
  39. GRB 241029A: GROWTH-India Telescope optical follow up
  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. GRB 241029A: GTC/OSIRIS+ spectroscopic redshift z=1.072
  47. MISTRAL@OHP photometric and spectroscopic observations of GRB 241029A
  48. GRB 241026A: Swift/UVOT Upper Limits
  49. GRB 241029A: AKO Optical Afterglow Detection
  50. EP241021a: continued SOAR observations confirm optical rebrightening
  51. GRB 241029A: Xinglong-2.16m optical afterglow confirmation
  52. GRB 241029A: Mephisto observations
  53. EP 241026b: LBT possible optical counterpart (brightening source)
  54. GRB 241029A: TRT optical afterglow candidate detection
  55. GRB 241029A: Swift ToO observations
  56. GRB 241029A : Detection and localization of a bright long GRB by SVOM/ECLAIRs
  57. GRB 241026A: TNOT optical counterpart detection
  58. GRB 241025A (EP241025a): Optical afterglow observations with the Tsinghua-Nanshan Optical Telescope
  59. GRB 241025A: further SAO RAS optical observations
  60. GRB 241026A: BTA and Zeiss-1000 optical observations
  61. GRB 241026A: SVOM/GRM observation
  62. EP241026B: GROWTH-India Telescope optical upper limit
  63. GRB 241025A: Swift/UVOT Detection
  64. GRB 241026A: GROWTH-India Telescope optical observations
  65. GRB 241026A: J-band observations with WINTER
  66. GRB 241025A: SAO RAS optical observations
  67. GRB 241026A: Las Cumbres optical detection
  68. GRB 241025A: Mondy optical observations
  69. EP241021a: SOAR observations of the optical counterpart
  70. EP241021a: further SAO RAS optical observations
  71. EP241026a (GRB 241026A): EP on-board trigger and follow-up observation
  72. EP 241026b: LBT optical observations
  73. GRB 241026A: Enhanced Swift-XRT position
  74. EP241026b: EP detection of a fast X-ray transient
  75. GRB 241026A: COLIBRÍ Detection of the Optical Counterpart
  76. GRB 241026A: SAO RAS observations of possible optical afterglow
  77. GRB 241026A: Swift detection of a burst
  78. GRB241025A: 1.3m DFOT optical afterglow detection
  79. EP241021a: optical follow-up observations with Xinglong Observatory
  80. GRB 241025A: GROWTH-India Telescope optical observations
  81. GRB 241025A: COLIBRÍ Detection of the Afterglow
  82. IPN triangulation of GRB 241022A (short/hard)
  83. LIGO/Virgo/KAGRA S241009l: Upper limits from Swift/BAT-GUANO
  84. EP241025a (GRB 241025A): EP observations update
  85. GRB 241025A : SVOM/VT optical afterglow observations
  86. EP 241021A: Swift ToO observations
  87. EP241021a: Liverpool Telescope optical follow-up observations
  88. GRB 241025A: Enhanced Swift-XRT position
  89. GRB 241025A: DDOTI Afterglow detection
  90. GRB 241025A: TRT optical afterglow observation
  91. GRB 241025A: Swift detection of a burst with an optical counterpart
  92. EP241021a: GTC OSIRIS+ spectroscopy of the optical counterpart
  93. GRB 241001A: ATCA radio observations
  94. GRB 241010A: VIRT Optical Upper Limit
  95. EP241021a: SAO RAS optical observations
  96. EP241021a: KAIT optical observations
  97. EP241021a: 1.3m DFOT Optical observations
  98. EP241021a: Optical upper limits with Kinder observations
  99. EP241021a: TRT optical observations
  100. GRB 241018A: SVOM/C-GFT optical observations

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