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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"

22096 results found.

  1. GRB 241029A: LCO optical detection
  2. Fermi trigger No 752006065: Global MASTER-Net observations report
  3. Swift GRB241030.77: Global MASTER-Net observations report
  4. GRB 241030A: COLIBRI Continuing Detection of the Afterglow
  5. GRB 241030B: SVOM/VT optical afterglow observations
  6. GRB 241030B: BTA observations
  7. GRB 241029A: SVOM/VT optical afterglow observations
  8. GRB 241030A: detection of the bright optical counterpart in ATLAS forced photometry
  9. GRB 241030B: optical observations from the INAF Asiago Observatory
  10. GRB241030B: GRANDMA/TAROT Upper Limit
  11. GRB 241030B: SAO RAS optical observations
  12. GRB 241030B: Nanshan/HMT optical afterglow detection
  13. Konus-Wind detection of GRB 241030A
  14. GRB 240912A: radio detection with the VLA
  15. Fermi GRB 241030A: Global MASTER-Net observations report
  16. Swift GRB 241030A: Global MASTER-Net observations report
  17. GRB 241030A: Swift/UVOT Detection
  18. EP 241021a: further Swift-XRT observations and X-ray counterpart detection
  19. GRB 241030A: SVOM/C-GFT optical observations
  20. GRB 241026A: LBT optical observations
  21. EP241021a: Optical rebrightening observations with Mephisto
  22. GRB 241030A: Multiband optical detection with Mephisto
  23. GRB 241030A: SVOM/VT optical afterglow observations
  24. GRB 241025A: The discovery of a BdHN I from data of Swift, Fermi, SVOM and Einstein Probe telescopes
  25. GRB 241030A: TRT optical observations
  26. GRB 241030A: Keck/LRIS spectroscopic redshift z = 1.411
  27. GRB 241030A: ULL-ASTRO-MASTER detection of a bright optical counterpart with the LCOGT 40-cm telescope at McDonald Observatory
  28. GRB 241030A: COLIBRÍ Detection of the Bright Optical Counterpart
  29. GRB 241029A: SAO RAS optical observations
  30. GRB 241026A: SAO RAS optical observations
  31. EP240919a / GRB 240919A: ATCA Detection of Radio Counterpart
  32. EP241021a: SAO RAS observations of rebrightening
  33. EP241021a: ATCA radio observations
  34. MISTRAL@OHP photometric and spectroscopic observations of GRB 241029A
  35. GRB 241026A: Swift/UVOT Upper Limits
  36. GRB 241029A: Swift-XRT observations
  37. GRB 241029A: GOTO optical afterglow detection
  38. EP241021a: continued SOAR observations confirm optical rebrightening
  39. GRB 241029A: MASTER early optical counterpart detection
  40. GRB 241029A: Xinglong-2.16m optical afterglow confirmation
  41. GRB 241029A: Mephisto observations
  42. EP 241026b: LBT possible optical counterpart (brightening source)
  43. GRB 241029A: TRT optical afterglow candidate detection
  44. GRB 241029A: Swift ToO observations
  45. Fermi trigger No 751861204: Global MASTER-Net observations report
  46. GRB 240821A: Keck/LRIS spectroscopic observations
  47. Konus-Wind detection of GRB 241025A
  48. GRB 241025A (EP241025a): Optical afterglow observations with the Tsinghua-Nanshan Optical Telescope
  49. GRB 241026A: LBT redshift confirmation
  50. GRB 241025A: further SAO RAS optical observations
  51. GRB 241026A: BTA and Zeiss-1000 optical observations
  52. EP241026B: GROWTH-India Telescope optical upper limit
  53. GRB 241025A: Swift/UVOT Detection
  54. GRB 241026A: GROWTH-India Telescope optical observations
  55. GRB 241026A: J-band observations with WINTER
  56. GRB 241025A: SAO RAS optical observations
  57. GRB 241025A: Mondy optical observations
  58. EP241021a: SOAR observations of the optical counterpart
  59. EP241021a: further SAO RAS optical observations
  60. EP 241026b: LBT optical observations
  61. EP241021a: e-MERLIN radio observation
  62. EP EP241026b: Global MASTER-Net observations report
  63. GRB 241026A: KAIT optical observations
  64. EP241026b: EP detection of a fast X-ray transient
  65. Fermi trigger No 751616906: Global MASTER-Net observations report
  66. GRB 241026A: COLIBRÍ Detection of the Optical Counterpart
  67. GRB 241026A: SAO RAS observations of possible optical afterglow
  68. Fermi GRB 241026A: Global MASTER-Net observations report
  69. Swift GRB241026.95: Global MASTER-Net observations report
  70. GRB241025A: 1.3m DFOT optical afterglow detection
  71. EP241021a: optical follow-up observations with Xinglong Observatory
  72. ​GRB 241025A: optical photometry from Konkoly
  73. GRB 241025A: GROWTH-India Telescope optical observations
  74. GRB 241025A: COLIBRÍ Detection of the Afterglow
  75. LIGO/Virgo/KAGRA S241009l: Upper limits from Swift/BAT-GUANO
  76. GRB 241025A: GRANDMA and Kilonova-Catcher optical afterglow detections and upperlimits
  77. Fermi trigger No 751563375: Global MASTER-Net observations report
  78. Fermi trigger No 751554401: Global MASTER-Net observations report
  79. EP241021a: Optical and NIR observations of counterpart with the Fraunhofer Telescope at Wendelstein Observatory
  80. EP241021a: Optical and NIR observations of counterpart with the Fraunhofer Telescope at Wendelstein Observatory
  81. EP 241021a: Swift-XRT observations
  82. EP241021a: optical follow-up observations with the Liverpool Telescope
  83. Fermi GRB 241025A: Global MASTER-Net observations report
  84. Swift GRB 241025A: Global MASTER-Net observations report
  85. EP241025a (GRB 241025A): EP observations update
  86. GRB 241025A : SVOM/VT optical afterglow observations
  87. EP 241021A: Swift ToO observations
  88. EP241021a: Liverpool Telescope optical follow-up observations
  89. GRB 241001A: JWST spectroscopic identification of a supernova counterpart
  90. GRB 241025A: TRT optical afterglow observation
  91. Fermi GRB 241024B: Global MASTER-Net observations report
  92. EP241021a: GTC OSIRIS+ spectroscopy of the optical counterpart
  93. GRB 241001A: ATCA radio observations
  94. Fermi trigger No 751449953: Global MASTER-Net observations report
  95. EP241021a: SAO RAS optical observations
  96. EP241021a: KAIT optical observations
  97. EP241021a: Optical counterpart observations with the Liverpool Telescope
  98. EP241021a: 1.3m DFOT Optical observations
  99. EP241021a: GSP detects optical candidate counterpart
  100. EP241021a: Optical upper limits with Kinder observations

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