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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"

21901 results found.

  1. GRB 260918A: SVOM/VT optical upper limits
  2. GRB 260917B: Mondy optical upper limit
  3. EP260917b: EP-WXT detection of an X-ray transient
  4. EP260917A: J-band upper limit with WINTER
  5. IPN triangulation of GRB 260810A
  6. GRB 260917B: EP-FXT follow-up observation
  7. EP260917a: COLIBRÍ optical upper limits
  8. GRB 260918A: LCO optical upper limits
  9. EP260917a: Einstein Probe detection of an X-ray transient
  10. GRB 260918A: SVOM/COLIBRÍ (FM-GFT) optical upper limits
  11. GRB 260918A: SVOM detection of a burst
  12. GRB 260917B: FRAM-Auger optical limits
  13. GRB 260915A: SVOM/ECLAIRs refined analysis
  14. GRB 260917B: WINTER J-band observations
  15. GRB 260917B: SVOM/VT optical observations
  16. GRB 260917B: LCO optical observation
  17. GRB 260917B: SVOM/COLIBRÍ (FM-GFT) optical counterpart candidate
  18. GRB 260917B: SVOM detection of a faint burst
  19. GRB 260915A: J-band upper limit with WINTER
  20. GRB 260909A: NOEMA detection
  21. GRB 260914A: Mondy and TShAO optical observations
  22. GRB 260914A: SVOM/ECLAIRs refined analysis
  23. GRB 260909A: Swift-XRT observations
  24. GRB 260915A: J-band upper limit by SYSU 80cm infrared telescope
  25. GRB 260915A: SVOM/C-GFT optical upper limits
  26. GRB 260915A: REM optical/NIR observations
  27. GRB 260914A: REM optical/NIR observations
  28. GRB 260914A: VLT/X-shooter observations and redshift confirmation
  29. GRB 260915A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  30. GRB 260915A: NOT optical upper limit
  31. GRB 260915A: SVOM/VT optical upper limits from VHF data
  32. Fermi GBM Sub-Threshold Detection of GRB 260915A
  33. GRB 260915A: LCO optical upper limits
  34. GRB 260915A: SVOM detection of a burst
  35. Fermi GBM Sub-Threshold Detection of GRB 260914A
  36. GRB 260914A: LCO optical observation
  37. GRB 260914A: SVOM/C-GFT optical observations
  38. GRB 260914A: SVOM/VT optical counterpart confirmation
  39. GRB 260914A: SVOM/VT optical observation from VHF data
  40. GRB 260914A: SVOM/COLIBRÍ (FM-GFT) possible optical counterpart candidate
  41. GRB 260914A: SVOM detection of a burst
  42. GRB 260913A: SVOM trigger sb26091302 is not an astrophysical event
  43. GRB 260913A: SVOM/C-GFT optical upper limit
  44. GRB 260913A: SVOM detection of a faint burst
  45. GRB 260909A: OSN 1.5m, CAHA 2.2m and GTC 10.4m optical upper limits
  46. GRB 260907A: SVOM/GRM observation
  47. GRB 260909A: CrAO and AbAO optical upper limits
  48. GRB 260909A: SVOM/ECLAIRs refined analysis
  49. GRB 260910B: GOTO tentative optical counterpart candidates
  50. GRB 260909A: KAIT optical upper limit
  51. GRB 260903A: Swift-XRT observations
  52. EP260806a: VLA+ALMA radio detections
  53. GRB 260909A: OHP/T193 z-band upper limit
  54. GRB 260909A: VLT optical and near-infrared upper limits
  55. EP260806a: NOEMA detection
  56. EP260623a: NOEMA detections
  57. GRB 260909A: SVOM/GRM observation
  58. GRB 260909A: Mondy optical observations and afterglow candidate
  59. GRB 260909A: Xinglong 2.16m optical upper limit
  60. GRB 260909A: SVOM/C-GFT optical upper limit
  61. GRB 260909A: SVOM detection of a burst
  62. GRB 260903A: SAO RAS optical upper limit
  63. GRB 260903A: J-band upper limit with WINTER
  64. GRB 260903A: SVOM/ECLAIRs refined analysis
  65. GRB260903A: Liverpool Telescope optical observations
  66. GRB 260903A: SAO RAS optical observations
  67. EP260903a: EP-WXT detection of a fast X-ray transient
  68. GRB 260903A: OHP/T193 optical afterglow detection
  69. NuSTAR Transient 260828: SOAR Optical Upper Limits
  70. GRB 260903A: LCO optical counterpart detection
  71. GRB 260903A: SVOM detection of a soft faint burst
  72. EP260901a: SVOM/VT optical upper limits
  73. Konus-Wind detection of GRB 260829A
  74. GRB 260829A: SVOM/GRM observation
  75. GRB 260818A: ATCA detection of a candidate radio counterpart
  76. EP260830a: EP-FXT follow-up observation
  77. GRB 260831B / sb26083106: SVOM/GWAC-F60A/B confirmation of optical variation of nova V* GK Per
  78. GRB 260831B / sb26083106: SVOM/VT optical variability of V* GK Per
  79. NuSTAR Transient 260828: LCO Optical Upper Limits
  80. EP260901a: EP-WXT detection of a fast X-ray transient
  81. GRB 260831B: LCO optical upper limits
  82. EP260830a: EP-WXT detection of a fast X-ray transient
  83. GRB 260827A: SVOM/GRM observation
  84. GRB 260831B: SVOM detection of a possible burst
  85. GRB 260825A: SVOM/GRM observation of a long burst
  86. GRB 260818B: Further EP-FXT observation
  87. GRB 260818B: VLT optical and nIR observations
  88. GRB 260818B: TNG NIR observations
  89. GRB 260818B: 6 GHz VLA observations
  90. GRB 260818B: SVOM/VT optical upper limit and continuous observations
  91. GRB 260818B: SVOM/COLIBRÍ (FM-GFT) optical counterpart candidate
  92. GRB 260808B: SAO RAS observations of the optical rebrightening
  93. GRB 260822A: SVOM/ECLAIRs refined analysis
  94. GRB 260809A: SVOM/ECLAIRs refined analysis
  95. GRB 260822A: SVOM/VT optical upper limits
  96. IceCube Alert 260825A: Global MASTER-Net observations report
  97. GRB 260822A: PRIME near-infrared upper limits from multiple epochs
  98. GRB 260822A: the candidate optical afterglow is an unrelated type-Ia SN
  99. EP260822a: EP-FXT non-detection and upper limit
  100. GRB 260822A: SVOM/COLIBRÍ (FM-GFT) possible optical counterpart candidate

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