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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"

32757 results found.

  1. GRB 240912A: radio detection with the VLA
  2. Fermi GRB 241030A: Global MASTER-Net observations report
  3. GRB 241030A: AKO Optical Afterglow Detection
  4. Swift GRB 241030A: Global MASTER-Net observations report
  5. GRB 241030A: Swift/UVOT Detection
  6. EP 241021a: further Swift-XRT observations and X-ray counterpart detection
  7. GRB 241030A: SVOM/GRM observation
  8. GRB 241026A: Swift-BAT refined analysis
  9. GRB 241030A: SVOM/C-GFT optical observations
  10. GRB 241026A: LBT optical observations
  11. EP241021a: Optical rebrightening observations with Mephisto
  12. EP241026b: EP-FXT follow-up observation
  13. GRB 241030A: Multiband optical detection with Mephisto
  14. GRB 241030A: SVOM/VT optical afterglow observations
  15. GRB 241025A: The discovery of a BdHN I from data of Swift, Fermi, SVOM and Einstein Probe telescopes
  16. GRB 241030A : MITSuME Akeno optical afterglow detection
  17. GRB 241029A: GROWTH-India Telescope optical follow up
  18. GRB 241030A: TRT optical observations
  19. GRB 241030A: Keck/LRIS spectroscopic redshift z = 1.411
  20. GRB 241030A: ULL-ASTRO-MASTER detection of a bright optical counterpart with the LCOGT 40-cm telescope at McDonald Observatory
  21. GRB 241030A: COLIBRÍ Detection of the Bright Optical Counterpart
  22. GRB 241029A: SAO RAS optical observations
  23. GRB 241026A: SAO RAS optical observations
  24. EP240919a / GRB 240919A: ATCA Detection of Radio Counterpart
  25. EP241021a: SAO RAS observations of rebrightening
  26. GRB 241029A: GTC/OSIRIS+ spectroscopic redshift z=1.072
  27. EP241021a: ATCA radio observations
  28. MISTRAL@OHP photometric and spectroscopic observations of GRB 241029A
  29. GRB 241026A: Swift/UVOT Upper Limits
  30. GRB 241029A: Swift-XRT observations
  31. GRB 241029A: Fermi GBM Observation
  32. GRB 241029A: AKO Optical Afterglow Detection
  33. GRB 241029A: GOTO optical afterglow detection
  34. EP241021a: continued SOAR observations confirm optical rebrightening
  35. GRB 241029A: MASTER early optical counterpart detection
  36. GRB 241029A: Xinglong-2.16m optical afterglow confirmation
  37. GRB 241029A: Mephisto observations
  38. EP 241026b: LBT possible optical counterpart (brightening source)
  39. GRB 241029A: TRT optical afterglow candidate detection
  40. GRB 241029A: Swift ToO observations
  41. GRB 241029A: SVOM/GRM observation
  42. GRB 241029A : Detection and localization of a bright long GRB by SVOM/ECLAIRs
  43. GRB 240821A: Keck/LRIS spectroscopic observations
  44. EP241021a: Gemini-South detection of optical rebrightening
  45. GRB 241026A: the 100th GRB detected by GRBAlpha
  46. GRB 241026A: TNOT optical counterpart detection
  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 241026A: GECAM detection
  51. GRB 241025A: further SAO RAS optical observations
  52. GRB 241026A: BTA and Zeiss-1000 optical observations
  53. GRB 241026A: SVOM/GRM observation
  54. EP241026B: GROWTH-India Telescope optical upper limit
  55. GRB 241025A: Swift/UVOT Detection
  56. GRB 241026A: GROWTH-India Telescope optical observations
  57. GRB 241026A Fermi GBM Analysis
  58. GRB 241026A: BTA redshift identification of z = 2.79
  59. GRB 241026A: J-band observations with WINTER
  60. GRB 241025A: SAO RAS optical observations
  61. GRB 241026A: Las Cumbres optical detection
  62. GRB 241025A: Mondy optical observations
  63. EP241021a: SOAR observations of the optical counterpart
  64. EP241021a: further SAO RAS optical observations
  65. EP241026a (GRB 241026A): EP on-board trigger and follow-up observation
  66. EP 241026b: LBT optical observations
  67. EP241021a: e-MERLIN radio observation
  68. EP EP241026b: Global MASTER-Net observations report
  69. GRB 241026A: KAIT optical observations
  70. GRB 241026A: COLIBRÍ Detection of the Optical Counterpart
  71. GRB 241026A: SAO RAS observations of possible optical afterglow
  72. Fermi GRB 241026A: Global MASTER-Net observations report
  73. GRB241025A: 1.3m DFOT optical afterglow detection
  74. EP241021a: optical follow-up observations with Xinglong Observatory
  75. ​GRB 241025A: optical photometry from Konkoly
  76. GRB 241025A: GROWTH-India Telescope optical observations
  77. GRB 241025A: COLIBRÍ Detection of the Afterglow
  78. GRB 241025C: Fermi GBM Detection
  79. GRB 241025A: Fermi GBM Observation
  80. GRB 241025A: GRANDMA and Kilonova-Catcher optical afterglow detections and upperlimits
  81. EP241021a: Optical and NIR observations of counterpart with the Fraunhofer Telescope at Wendelstein Observatory
  82. EP241021a: Optical and NIR observations of counterpart with the Fraunhofer Telescope at Wendelstein Observatory
  83. EP 241021a: Swift-XRT observations
  84. EP241021a: optical follow-up observations with the Liverpool Telescope
  85. Fermi GRB 241025A: Global MASTER-Net observations report
  86. Swift GRB 241025A: Global MASTER-Net observations report
  87. EP241025a (GRB 241025A): EP observations update
  88. GRB 241025A : SVOM/VT optical afterglow observations
  89. EP 241021A: Swift ToO 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: DDOTI Afterglow detection
  94. EP241025a (GRB 241025A): EP on-board trigger and autonomous follow-up observation
  95. GRB 241025A: SVOM/GRM observation
  96. GRB 241025A: TRT optical afterglow observation
  97. Fermi GRB 241024B: Global MASTER-Net observations report
  98. EP241021a: GTC OSIRIS+ spectroscopy of the optical counterpart
  99. GRB 241001A: ATCA radio observations
  100. EP241021a: No Detection in Fermi-GBM Observation

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