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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"

11661 results found.

  1. Fermi GRB 241104A: Global MASTER-Net observations report
  2. GRB 241104A: Fermi GBM Final Real-time Localization
  3. GRB 241030A: GRBAlpha detection
  4. Fermi trigger No 752365806: Global MASTER-Net observations report
  5. GRB 241030A: Rapid release of TESS data.
  6. GRB 241029A: GRBAlpha detection
  7. Kinder optical follow-up observations of EP241021a, EP241026b, and EP241030a/GRB241030A
  8. GRB241030A: OHP/T193 optical observations
  9. EP241030a: Futher EP-FXT observation of the X-ray Afterglow of GRB 241030A
  10. GRB 241026A: SAO RAS optical observations
  11. GRB 241030A / EP241030a: GMG possible spectroscopic redshift at z ~ 1.4
  12. EP241030a: EP/FXT observation of GRB 241030A X-ray Afterglow
  13. GRB 241030B: Montarrenti Observatory optical upper limit
  14. GRB 241030A / EP241030a: FTW Optical and NIR observations of the optical counterpart
  15. Fermi trigger No 752083996: Global MASTER-Net observations report
  16. GRB 241030A: Fermi GBM Observation
  17. GRB 241030B : GIT optical upper limits
  18. GRB 241030B: LCOGT Optical Upper Limits
  19. GRB 241029A: COLIBRI Detection of the Optical Counterpart
  20. Fermi trigger No 752006065: Global MASTER-Net observations report
  21. GRB 241030B: GTC/OSIRIS+ tentative spectroscopic redshift z = 2.82
  22. GRB 241030B: SVOM/GRM observation
  23. GRB 241030B : MITSuME Akeno optical upper limits
  24. GRB 241030A: COLIBRI Continuing Detection of the Afterglow
  25. GRB 241030B: SVOM/VT optical afterglow observations
  26. GRB 241030B: COLIBRÍ Upper Limits on the Optical Counterpart
  27. EP241030a: EP detection of GRB 241030A X-ray Afterglow
  28. GRB241030B: Fermi GBM Observation
  29. GRB 241030B: BTA observations
  30. GRB 241029A: SVOM/VT optical afterglow observations
  31. GRB 241030A: detection of the bright optical counterpart in ATLAS forced photometry
  32. GRB 241030B: optical observations from the INAF Asiago Observatory
  33. GRB 241030B: SAO RAS optical observations
  34. GRB 241030B: AKO Optical Afterglow Detection
  35. GRB 241030B: Nanshan/HMT optical afterglow detection
  36. GRB 241030B: SVOM/ECLAIRs detection of a burst
  37. Konus-Wind detection of GRB 241030A
  38. GRB 241030B: Fermi GBM Final Real-time Localization
  39. GRB 241030A: Fermi-LAT detection
  40. GRB 240912A: radio detection with the VLA
  41. Fermi GRB 241030A: Global MASTER-Net observations report
  42. GRB 241030A: AKO Optical Afterglow Detection
  43. GRB 241030A: Swift/UVOT Detection
  44. GRB 241030A: SVOM/GRM observation
  45. GRB 241030A: SVOM/C-GFT optical observations
  46. GRB 241030A: Multiband optical detection with Mephisto
  47. GRB 241030A: SVOM/VT optical afterglow observations
  48. GRB 241025A: The discovery of a BdHN I from data of Swift, Fermi, SVOM and Einstein Probe telescopes
  49. GRB 241030A : MITSuME Akeno optical afterglow detection
  50. GRB 241029A: GROWTH-India Telescope optical follow up
  51. GRB 241030A: TRT optical observations
  52. GRB 241030A: ULL-ASTRO-MASTER detection of a bright optical counterpart with the LCOGT 40-cm telescope at McDonald Observatory
  53. GRB 241030A: COLIBRÍ Detection of the Bright Optical Counterpart
  54. GRB 241030A: Fermi GBM Final Real-time Localization
  55. GRB 241029A: SAO RAS optical observations
  56. GRB 241026A: SAO RAS optical observations
  57. GRB 241029A: GTC/OSIRIS+ spectroscopic redshift z=1.072
  58. MISTRAL@OHP photometric and spectroscopic observations of GRB 241029A
  59. GRB 241029A: Fermi GBM Observation
  60. GRB 241029A: AKO Optical Afterglow Detection
  61. GRB 241029A: GOTO optical afterglow detection
  62. GRB 241029A: MASTER early optical counterpart detection
  63. GRB 241029A: Xinglong-2.16m optical afterglow confirmation
  64. GRB 241029A: Mephisto observations
  65. GRB 241029A: TRT optical afterglow candidate detection
  66. GRB 241029A: SVOM/GRM observation
  67. GRB 241029A : Detection and localization of a bright long GRB by SVOM/ECLAIRs
  68. Fermi trigger No 751861204: Global MASTER-Net observations report
  69. GRB 241029A: Fermi GBM Final Real-time Localization
  70. GRB 241026A: the 100th GRB detected by GRBAlpha
  71. GRB 241026A: TNOT optical counterpart detection
  72. Konus-Wind detection of GRB 241025A
  73. GRB 241025A (EP241025a): Optical afterglow observations with the Tsinghua-Nanshan Optical Telescope
  74. GRB 241026A: GECAM detection
  75. GRB 241025A: further SAO RAS optical observations
  76. GRB 241026A: BTA and Zeiss-1000 optical observations
  77. GRB 241026A: SVOM/GRM observation
  78. GRB 241026A: GROWTH-India Telescope optical observations
  79. GRB 241026A Fermi GBM Analysis
  80. GRB 241026A: BTA redshift identification of z = 2.79
  81. GRB 241026A: J-band observations with WINTER
  82. GRB 241026A: Las Cumbres optical detection
  83. EP241026a (GRB 241026A): EP on-board trigger and follow-up observation
  84. Fermi trigger No 751616906: Global MASTER-Net observations report
  85. GRB 241026A: COLIBRÍ Detection of the Optical Counterpart
  86. GRB 241026A: SAO RAS observations of possible optical afterglow
  87. Fermi GRB 241026A: Global MASTER-Net observations report
  88. GRB 241026A: Fermi GBM Final Real-time Localization
  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 241025C: Fermi GBM Detection
  93. GRB 241025A: Fermi GBM Observation
  94. GRB 241025C: Fermi GBM Final Localization
  95. GRB 241025B: Fermi GBM Final Localization
  96. Fermi trigger No 751563375: Global MASTER-Net observations report
  97. Fermi trigger No 751554401: Global MASTER-Net observations report
  98. Fermi GRB 241025A: Global MASTER-Net observations report
  99. EP241025a (GRB 241025A): EP observations update
  100. GRB 241025A : SVOM/VT optical afterglow observations

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