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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

22062 results found.

  1. Fermi trigger No 747163821: Global MASTER-Net observations report
  2. LIGO/Virgo/KAGRA S240825ar: Upper limits from Swift/BAT-GUANO
  3. LIGO/Virgo/KAGRA S240807h: Upper limits from Swift/BAT-GUANO
  4. GRB 240825A: Magnitude Correction in SVOM/C-GFT Optical Observations
  5. GRB 240825A: MeerLICHT afterglow detection
  6. Fermi trigger No 746923430: Global MASTER-Net observations report
  7. GRB 240828A: SAO RAS AS-500(2) optical observations
  8. GRB 240821A: VLT spectroscopic observations
  9. Fermi trigger No 746882332: Global MASTER-Net observations report
  10. GRB240828B: REM optical/NIR upper limits
  11. Fermi trigger No 746816563: Global MASTER-Net observations report
  12. GRB 240825A: SOAR observations
  13. GRB 240828B: Mephisto optical upper limit
  14. GRB 240828B: GRANDMA Optical Upper Limit
  15. LIGO/Virgo/KAGRA S240830gn: Coverage and upper limits from MAXI/GSC observations
  16. GRB 240825A: MeerKAT detection
  17. GRB 240828B: J-band upper limit from WINTER
  18. Fermi trigger No 746684112: Global MASTER-Net observations report
  19. GRB 240828A: KAIT continued optical observations
  20. GRB 240828A: SAO RAS optical observations
  21. Fermi trigger No 746587425: Global MASTER-Net observations report
  22. GRB 240828A: KAIT Optical Afterglow Candidate
  23. GRB 240825A: SVOM/VT optical detection
  24. GRB 240828A: Swift-XRT afterglow detection
  25. GRB 240825A: further SAO RAS optical observations
  26. GRB 240825A: iTelescope optical observations
  27. GRB 240828B: Swift-XRT afterglow detection
  28. Swift GRB240829.16: Global MASTER-Net observations report
  29. GRB 240828A: Tiled Swift observations
  30. LAT GRB240828.62: Global MASTER-Net observations report
  31. Fermi GRB 240828A: Bassano Bresciano Observatory upper limit
  32. GRB 240819A as a likely X-Ray Flash
  33. GRB 240828B: Swift ToO observations
  34. GRB 240821A: PRIME near-infrared observations
  35. GRB 240825A: VLA detection
  36. Fermi GRB 240828A: Global MASTER-Net observations report
  37. Fermi trigger No 746438824: Global MASTER-Net observations report
  38. SVOM GRB 240821A: optical afterglow discovery
  39. GRB 240821A: the second and third EP-FXT follow-up observations and afterglow candidates
  40. GRB 240825A: ALMA detection
  41. GRB 240825A: SAO RAS optical observations
  42. GRB 240824A: GIT optical upper limit
  43. GRB 240825A: TNG optical photometry and spectroscopy
  44. GRB 240825A: NUTTelA-TAO / BSTI Optical Limits
  45. GRB 240824B: Ondrejov D50 optical limit
  46. GRB 240825A: KAIT optical observations
  47. GRB 240825A: PRIME near-infrared detection
  48. Konus-Wind detection of GRB 240825A (bright/long)
  49. GRB 240825A: AKO Optical Follow-Up Observations
  50. GRB 240825A: Swift/UVOT Detection
  51. GRB 240825A: REM detection of the optical/NIR afterglow
  52. GRB 240825A: SVOM/C-GFT optical observations
  53. GRB 240825A: Montarrenti Observatory optical observations
  54. GRB 240825A: MASTER optical counterpart observation
  55. GRB 240825A: LCO optical observations
  56. SGR 1E 1841-045 / Kes 73 (Trigger 1249878): Osservatorio Atronomico Nastro Verde optical upper limit
  57. Fermi GRB 240825A: Global MASTER-Net observations report
  58. SGR 1E 1841-045 / Kes 73 (Trigger 1249653) - Osservatorio Astronomico Nastro Verde upper limit
  59. GRB 240824B: NOT optical upper limit
  60. Swift GRB 240825A: Global MASTER-Net observations report
  61. GRB 240825A: 1.6m Mephisto multi-band detection
  62. GRB 240825A: Skynet Optical Afterglow observations
  63. GRB 240825A: Nanshan/HMT optical afterglow observations
  64. GRB 240824B: Swift-XRT afterglow detection
  65. GRB 240824A: Swift-XRT observations
  66. GRB 240824B: Swift/BAT arcminute localization of a burst
  67. GRB 240824B: Swift ToO observations
  68. Fermi GRB 240824C: Global MASTER-Net observations report
  69. GRB 240824A: Swift/UVOT Upper Limits
  70. GRB 240821A: Swift/UVOT observations of the XRT sources.
  71. GRB240824A: GRANDMA/TAROT-TCA Upper Limit
  72. SGR 1E 1841-045 / Kes 73: Leavitt Observatory optical upper limit
  73. GRB 240824A: KAIT optical upper limit
  74. GRB 240824A: Skynet Optical Afterglow Discovery
  75. Swift GRB240824.04: Global MASTER-Net observations report
  76. SGR 1E 1841-045 / Kes 73: Montarrenti Observatory optical upper limits
  77. GRB 240821A: Colibri Optical Upper Limit
  78. EP240820a: PRIME J-band Observations
  79. GRB 240821A: Swift-XRT observations
  80. GRB 240821A: REM optical/NIR upper limits
  81. GRB 240821A: LCO optical observations
  82. GRB 240821A: JinShan optical upper limits
  83. GRB 240809A: Mondy and AbAO Optical Observations
  84. GRB 240821A: SVOM/VT follow-up and optical upper limit
  85. Fermi GRB 240821A: Global MASTER-Net observations report
  86. Fermi trigger No 745964969: Global MASTER-Net observations report
  87. Fermi trigger No 745925274: Global MASTER-Net observations report
  88. GRB 240821A: Swift ToO observations
  89. Fermi trigger No 746019401: Global MASTER-Net observations report
  90. Fermi-GBM Observations of the reactivation of SGR 1E 1841-045 / Kes 73
  91. Fermi trigger No 745935375: Global MASTER-Net observations report
  92. Fermi GRB 240821B: Global MASTER-Net observations report
  93. EP240801a: Keck/LRIS spectroscopic redshift confirmation
  94. GRB 240821A: GRANDMA/LesMakes-T60 Upper Limit
  95. Fermi trigger No 745866488: Global MASTER-Net observations report
  96. GRB 240819A: Swift-XRT observations
  97. GRB 240819A: JinShan optical upper limits on one Swift/XRT source
  98. EP240820a: TRT optical upper limit
  99. EP240820a: EP detection of a fast X-ray transient
  100. GRB 240819A: KAIT optical upper limit

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