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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"

27297 results found.

  1. GRB 231122A: GECAM detection
  2. GRB 231122B: GECAM detection
  3. GRB 231122A: Fermi GBM Final Real-time Localization
  4. GRB 231117A: GTC Near-Infrared Observations
  5. GRB 231117A: Swift-BAT refined analysis
  6. GRB 231118A: GRBAlpha detection
  7. LIGO/Virgo/KAGRA S231118d: Upper limits from Swift/BAT-GUANO
  8. LIGO/Virgo/KAGRA S231118an: Upper limits from Swift/BAT-GUANO
  9. LIGO/Virgo/KAGRA S231114n: Upper limits from Swift/BAT-GUANO
  10. LIGO/Virgo/KAGRA S231113bb: Upper limits from Swift/BAT-GUANO
  11. GRB 231118A: VZLUSAT-2 detection
  12. GRB 231118A: Swift-BAT refined analysis
  13. GRB 231118B: CALET Gamma-Ray Burst Monitor detection
  14. GRB 231117A: CALET Gamma-Ray Burst Monitor detection
  15. 231118A: Swift-UVOT Detection
  16. GRB231117A: Swift-UVOT detection
  17. GRB 231117A : MITSuME Akeno optical afterglow candidate detection
  18. GRB 231118B: Fermi GBM observation
  19. GRB 231118A: Fermi GBM observation
  20. LIGO/Virgo/KAGRA S231119ab: Coverage and upper limits from MAXI/GSC observations
  21. GRB 231120A: Fermi GBM Final Real-time Localization
  22. GRB 231117A: Swift-XRT refined Analysis
  23. GRB 231118A: Swift-XRT refined Analysis
  24. GRB 231118A: MeerLICHT afterglow detection
  25. LIGO/Virgo/KAGRA S231119u: One counterpart neutrino candidate from IceCube neutrino searches
  26. GRB 231117A: OHP/T120 optical observations
  27. GRB 231118A: VLT/X-shooter redshift
  28. Fermi trigger No 722039659: Global MASTER-Net observations report
  29. GRB 231117A: GECAM-C detection
  30. GRB 231115A: Upper limit from CALET Gamma-Ray Burst Monitor
  31. GRB 231118A: Las Cumbres optical detection
  32. GRB 231118B: BALROG localization (Fermi Trigger 722039659 / GRB 231118940)
  33. GRB 231118B: Fermi GBM Final Real-time Localization
  34. GRB 231118A: LCOGT Optical Observations
  35. GRB 231118A: Continued Skynet Observations
  36. Swift GRB231118.72: Global MASTER-Net observations report
  37. GRB 231117A: Kinder observations with Lulin observatory for AT 2023yba without fading in r band
  38. GRB 231118A: Skynet Optical Afterglow Discovery
  39. GRB 231118A: Swift detection of a burst
  40. GRB 231118A: Fermi GBM Final Real-time Localization
  41. GRB 231117A: Lowell Discovery Telescope Observations
  42. GRB 231117A: GRBAlpha detection
  43. GRB 231117A: Keck spectroscopy of afterglow candidate
  44. GRB 231115A: JinShan optical upper limits
  45. GRB 231117A: GIT optical follow-up
  46. GRB 231117A: LT observations consistent with fading
  47. GRB 231117A: AKO Optical Upper Limit
  48. GRB 231117A: afterglow candidate detection from Kinder observations with Lulin observatory
  49. Swift GRB 231117A: Global MASTER-Net observations report
  50. GRB 231117A: ATLAS non-detection of an optical counterpart
  51. GRB 231115A : OHP/T120 optical upper limit
  52. GRB 231117A : MITSuME Akeno optical upper limits
  53. GRB 231117A: GOTO optical upper limits
  54. GRB 231117A: AstroSat CZTI detection of a bright short burst
  55. GRB 231117A: Swift detection of a bright short burst
  56. GRB 231115A: Non-detection of radio emission with CHIME/FRB
  57. GRB 231111A: Swift/UVOT Detection
  58. GRB 231115A: NuSTAR Follow-Up Observations
  59. GRB 231115A: Swift/BAT-GUANO detection of a short burst
  60. Fermi GRB 231116A: Global MASTER-Net observations report
  61. GRB 231115A: AGILE/MCAL upper limits
  62. GRB 231115A: Insight-HXMT/HE detection
  63. GRB 231115A: GBM/Fermi Observations of a probable Giant Flare of Magnetar
  64. GRB 231116A: Fermi GBM Final Real-time Localization
  65. GRB 231115A : MITSuME Akeno and Okayama optical upper limits
  66. GRB 231115A: Gaoyazi/GOT follow-up and archival observations
  67. GRB 231115A: Upper limits from a neutrino search with IceCube
  68. GRB 231115A: Kinder observations with Lulin observatory
  69. GRB231115A: GRANDMA Observations
  70. GRB 231115A: GOTO pre-burst limits of AT2023xvj
  71. GRB 231115A: pre-burst ZTF upper limits for GRB optical counterpart candidate
  72. GRB 231106A: TESS identification of candidate optical counterpart
  73. GRB 231115A: MASTER optical observations
  74. GRB 231115A: Fermi Observations of a probable Magnetar Giant Flare from M82
  75. Integral GRB231115.65: Global MASTER-Net observations report
  76. GRB 231115A: GROWTH-India discovery of a potential optical counterpart
  77. Fermi GRB 231115A: Global MASTER-Net observations report
  78. GRB 231115A: Fermi GBM Final Real-time Localization
  79. GRB 231111A: Swift-BAT refined analysis
  80. LIGO/Virgo/KAGRA S231113bw: Zwicky Transient Facility observations
  81. Fermi GRB 231114A: Global MASTER-Net observations report
  82. LIGO/Virgo/KAGRA S231113bw: GROWTH-India coverage and upper limits
  83. GECAM-B observation of a short burst from SGR J1555-5402
  84. GRB 231114A: Fermi GBM Final Localization
  85. SGRJ1555-5402: Swift/BAT-GUANO arcminute localization of a SGR flare
  86. LIGO/Virgo/KAGRA S231113bw: Upper limits from Fermi-GBM Observations
  87. GRB 231110A: CALET Gamma-Ray Burst Monitor detection
  88. LIGO/Virgo/KAGRA S231113cd: Coverage and upper limits from MAXI/GSC observations
  89. LIGO/Virgo/KAGRA S231113bw: Coverage and upper limits from MAXI/GSC observations
  90. GRB 231110A: Swift-BAT refined analysis
  91. GRB 231111A: Xinglong-2.16m optical observations
  92. GRB 231104A: VZLUSAT-2 detection
  93. GRB 231111A NUTTelA-TAO / BSTI Early Measurements
  94. GRB 231111A: Leavitt Observatory optical observations
  95. GRB 231111A: GMG observation (correction)
  96. LIGO/Virgo/KAGRA S231112ag: Retraction of GW compact binary merger candidate
  97. GRB 231111A: GMG observation upper limit
  98. GRB 231106B: GRBAlpha detection
  99. GRB 231111A: Osservatorio Astronomico "Nastro Verde" optical observations with detection of an optical counterpart
  100. GRB 231111A: Swift-XRT refined Analysis

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