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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"

32766 results found.

  1. X-ray transient EP240315a: Kitab observatory optical upper limitns
  2. X-ray transient EP240315a: Montarrenti Observatory optical upper limit
  3. Fermi GRB 240317B: Global MASTER-Net observations report
  4. Fermi GRB 240317A: Global MASTER-Net observations report
  5. X-ray transient EP240315a: orphan FXT?
  6. X-ray transient EP240315a: Kinder follow-up observations for AT 2024eju with Lulin observatory
  7. X-ray transient EP240315a: GROND J-band detection
  8. X-ray transient EP240315a: VLT/X-shooter spectroscopic redshift of z = 4.859
  9. X-ray transient EP240315a: Nanshan/HMT optical upper limit
  10. AT2024eju: followup observations with Liverpool Telescope suggest a fading transient
  11. X-ray transient EP240315a: ATLAS detection of a possible optical counterpart AT2024eju
  12. GRID detection of GRB 240306A
  13. Changes to the Fermi-GBM Triggering Thresholds
  14. Fermi GRB 240314A: Global MASTER-Net observations report
  15. GRB240204A: VIRT optical upper limit
  16. GRB 240312A: Glowbug gamma-ray detection
  17. GRB 240310A: MASTER OT J200702.72-263928.7 inside 3sigma
  18. Fermi-LAT gamma-ray observations of IceCube-240307A
  19. Fermi GRB 240310A: Global MASTER-Net observations report
  20. IceCube-240307A: Upper limits from a search for additional neutrino events in IceCube
  21. GRID detection of GRB 240229A (Updated Report)
  22. GRID detection of GRB 240229A
  23. GRB 231215A: further radio observations with the VLA
  24. GRB 240306A: Fermi GBM observation
  25. GRB 240229A: Glowbug gamma-ray detection
  26. GRB 240227A (short): Glowbug gamma-ray detection
  27. GRB 240229A: GRBAlpha detection
  28. Konus-Wind detection of GRB 231118A
  29. GRB 240306A: AstroSat CZTI detection
  30. Fermi GRB 240306A: Global MASTER-Net observations report
  31. Fermi GRB 240305A: Global MASTER-Net observations report
  32. GRB 240305A: Fermi GBM observation
  33. Fermi-LAT gamma-ray observations of IceCube-240229A
  34. GRB 240305C: AstroSat CZTI detection of a short burst
  35. Fermi GRB 240305C: Global MASTER-Net observations report
  36. GRB 240305A: Swift/BAT-GUANO arcminute localization of a burst
  37. GRB 240218A: ALMA detection
  38. GRB 240218A: Chandra Detection and Jet Break Confirmation
  39. Konus-Wind detection of GRB 240227A (short/hard)
  40. GRB 240303B: VZLUSAT-2 detection
  41. GRB 240229A: VZLUSAT-2 detection
  42. Improved IPN triangulation of GRB 240227A (short)
  43. IPN triangulation of GRB 240229A
  44. GRB240218A: ATCA observation of the radio counterpart
  45. Transient EPW20240219aa: Optical observations with LDT
  46. Konus-Wind detection of GRB 240303B
  47. Swift Trigger 1218645: Another detection of Swift J151857.0-572147
  48. IPN triangulation of GRB 240303B
  49. Swift J151857.0-572147: Swift-BAT refined analysis
  50. GRB 240303B: Fermi GBM Detection
  51. GRB 240225B: Swift-XRT afterglow detection
  52. Swift detection of Swift J151857.0-572147
  53. GRB 240303B: CALET Gamma-Ray Burst Monitor detection
  54. Swift GRB 240303A: Global MASTER-Net observations report
  55. Swift J151857.0-572147: Confirmation of a new galactic transient
  56. GRB 240225B: Glowbug gamma-ray detection
  57. IceCube-240229A: Upper limits from a search for additional neutrino events in IceCube
  58. GRB 240225C: Glowbug gamma-ray detection
  59. GRB 240225A (short): Glowbug gamma-ray detection
  60. GRB 240229A: DDOTI Upper Limits on the Afterglow
  61. GRB 240218A: NOEMA upper limit
  62. GRB 240229A: CALET Gamma-Ray Burst Monitor detection
  63. GRB 240225B: further SAO RAS optical observations
  64. Fermi GRB 240229A: Global MASTER-Net observations report
  65. GRB 240225B: Swift ToO observations
  66. Konus-Wind detection of GRB 240225B (long)
  67. GRB 240225B: VLT/X-shooter redshift
  68. GRB 240225B : MITSuME Akeno optical afterglow candidate detection
  69. GRB 240225B: 3.6m DOT observation
  70. GRB 240225B: WINTER near-IR observations and upper limits
  71. GRB 240225B: SAO RAS optical observations
  72. GRB 240226A: GRBAlpha detection
  73. GRB 240225B: Mondy afterglow observations
  74. Fermi GRB 240227A: Global MASTER-Net observations report
  75. GRB 240225B: Liverpool Telescope afterglow observations
  76. Swift J1727.8-1613 (GRB 230824A): Madrona Peak Observatory - optical follow-up
  77. IPN triangulation of GRB 240227A (short)
  78. GRB 240225B: Liverpool Telescope optical afterglow observations
  79. GRB 240225B: NOT optical observations
  80. GRB 240218A: CMO SAI NIR upper limit
  81. Fermi GRB 240226A: Global MASTER-Net observations report
  82. Fermi Gamma-ray Burst Monitor trigger 730618809/240226236 is not a GRB
  83. GRB 240225B: Nanshan/HMT optical afterglow detection
  84. GRB 240225B: CALET Gamma-Ray Burst Monitor detection
  85. Transient EPW20240219aa: Kp-band imaging observations with NIRES
  86. Transient EPW20240219aa: J-band upper limits from WINTER
  87. GRB 240225C: CALET Gamma-Ray Burst Monitor detection
  88. GRB 240225B: GOTO detection of a candidate optical afterglow
  89. Transient EPW20240219aa: REM optical/NIR upper limits
  90. GRB 240225C: GRBAlpha detection
  91. GRB 240222A: ATCA radio observations
  92. GRB 240225B: AstroSat CZTI detection
  93. GRB 240225B: Tiled Swift observations
  94. Transient EPW20240219aa: Xinglong-2.16m optical upper limit
  95. GRB 240218A: VLA detection
  96. GRB 240222A: GRBAlpha detection
  97. Transient EPW20240219aa: GECKO: LOAO Optical Upper Limits
  98. Transient EPW20240219aa: 7DT Optical Upper Limits
  99. VLA X-band observation of EPW20240219aa
  100. Transient EPW20240219aa: Mondy optical observations

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