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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"

28233 results found.

  1. GRB 260917B: LCO optical observation
  2. GRB 260917B: SVOM/COLIBRÍ (FM-GFT) optical counterpart candidate
  3. GRB 260917B: SVOM detection of a faint burst
  4. GRB 260917A: BALROG localization (Fermi Trigger 811304653 / GRB 260917100)
  5. Fermi trigger No 811304653: Global MASTER-Net observations report
  6. GRB 260915A: J-band upper limit with WINTER
  7. Fermi trigger No 811264269: Global MASTER-Net observations report
  8. GRB 260909A: NOEMA detection
  9. GRB 260914A: Mondy and TShAO optical observations
  10. GRB 260914A: SVOM/ECLAIRs refined analysis
  11. GRB 260909A: Swift-XRT observations
  12. GRB 260916A: MAXI/GSC detection
  13. MAXI GRB260916.37: Global MASTER-Net observations report
  14. GRB 260915A: J-band upper limit by SYSU 80cm infrared telescope
  15. GRB 260915A: SVOM/C-GFT optical upper limits
  16. GRB 260915A: EP-FXT follow-up observation
  17. GRB 260915A: SVOM/VT refined early optical upper limits
  18. GRB 260915A: REM optical/NIR observations
  19. GRB 260914A: REM optical/NIR observations
  20. GRB 260914A: VLT/X-shooter observations and redshift confirmation
  21. GRB 260915A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  22. GRB 260915A: NOT optical upper limit
  23. SVOM GRB260915.05: Global MASTER-Net observations report
  24. GRB 260915A: SVOM/VT optical upper limits from VHF data
  25. Fermi GBM Sub-Threshold Detection of GRB 260915A
  26. GRB 260915A: LCO optical upper limits
  27. EP Alert 260914.53: Global MASTER-Net observations report
  28. GRB 260914A: EP-FXT follow-up observation
  29. GRB 260915A: SVOM detection of a burst
  30. Fermi GBM Sub-Threshold Detection of GRB 260914A
  31. GRB 260914A: LCO optical observation
  32. GRB 260914A: SVOM/C-GFT optical observations
  33. GRB 260914A: SVOM/VT optical observation from VHF data
  34. GRB 260914A: SVOM/COLIBRÍ (FM-GFT) possible optical counterpart candidate
  35. SVOM GRB260914.47: Global MASTER-Net observations report
  36. GRB 260914A: SVOM detection of a burst
  37. GRB 260913A: SVOM trigger sb26091302 is not an astrophysical event
  38. GRB 260818A: Continued ATCA observations
  39. SVOM GRB260913.32: Global MASTER-Net observations report
  40. GRB 260913A: SVOM/C-GFT optical upper limit
  41. GRB 260913A: SVOM detection of a faint burst
  42. GRB 260909A: OSN 1.5m, CAHA 2.2m and GTC 10.4m optical upper limits
  43. GRB 260907A: SVOM/GRM observation
  44. GRB 260909A: CrAO and AbAO optical upper limits
  45. GRB 260909A: KAIT optical upper limit
  46. GRB 260903A: Swift-XRT observations
  47. GRB 260909A: OHP/T193 z-band upper limit
  48. GRB 260909A: VLT optical and near-infrared upper limits
  49. EP Alert 260909.53: Global MASTER-Net observations report
  50. GRB 260909A: EP-FXT follow-up observation
  51. EP260806a: NOEMA detection
  52. EP260623a: NOEMA detections
  53. GRB 260909A: Mondy optical observations and afterglow candidate
  54. GRB 260909A: Xinglong 2.16m optical upper limit
  55. GRB 260909A: SVOM/C-GFT optical upper limit
  56. GRB 260909A: SVOM detection of a burst
  57. Fermi trigger No 810554827: Global MASTER-Net observations report
  58. EP Alert 260908.60: Global MASTER-Net observations report
  59. GRB 260907A: Glowbug gamma-ray detection of a likely short burst
  60. Fermi GRB 260907B: Global MASTER-Net observations report
  61. GRB 260903A: SAO RAS optical upper limit
  62. Fermi GRB 260907A: Global MASTER-Net observations report
  63. EP260903a: EP-FXT follow-up observation
  64. EP Alert 260905.11: Global MASTER-Net observations report
  65. GRB 260903A: J-band upper limit with WINTER
  66. EP Alert 260903.47: Global MASTER-Net observations report
  67. GRB260903A: Liverpool Telescope optical observations
  68. GRB 260903A: SAO RAS optical observations
  69. GRB 260830A: GECAM-B detection of a burst
  70. EP260903a: EP-WXT detection of a fast X-ray transient
  71. EP Alert 260903.62: Global MASTER-Net observations report
  72. GRB 260830A: Insight-HXMT/HE detection
  73. GRB 260903A: EP-FXT follow-up observation
  74. GRB 260903A: OHP/T193 optical afterglow detection
  75. NuSTAR Transient 260828: SOAR Optical Upper Limits
  76. SVOM GRB260903A: Global MASTER-Net observations report
  77. GRB 260903A: LCO optical counterpart detection
  78. GRB 260827A: Insight-HXMT/HE detection
  79. EP260901a: SVOM/VT optical upper limits
  80. EP260901a: EP-FXT follow-up observation
  81. GRB 260829A: SVOM/GRM observation
  82. GRB 260818A: ATCA detection of a candidate radio counterpart
  83. EP260830a: EP-FXT follow-up observation
  84. EP260901a: Global MASTER-Net observations report
  85. GRB 260831B / sb26083106: SVOM/GWAC-F60A/B confirmation of optical variation of nova V* GK Per
  86. NuSTAR Transient 260828: LCO Optical Upper Limits
  87. EP260901a: EP-WXT detection of a fast X-ray transient
  88. GRB 260830A: NuSTAR detection of prompt emission
  89. GRB 260831B: LCO optical upper limits
  90. EP260830a: Global MASTER-Net observations report
  91. EP260830a: EP-WXT detection of a fast X-ray transient
  92. GRB 260827A: SVOM/GRM observation
  93. NuSTAR 260828: a 1100s hard X-ray transient
  94. GRB 260831B: SVOM detection of a possible burst
  95. GRB 260827A: Glowbug gamma-ray detection
  96. Fermi-LAT Gamma-ray Observations of IceCube-260827A
  97. Fermi-LAT Gamma-ray Observations of IceCube-260825A
  98. GRB 260825A: SVOM/GRM observation of a long burst
  99. GRB 260829A: Fermi GBM Detection
  100. GRB 260825A: AstroSat CZTI detection

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