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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"

37787 results found.

  1. GRB 231111A: Optical follow-up observations at Terskol, AbAO, Maidanak, Mondy, Assy
  2. GRB 231126A: Fermi GBM Final Real-time Localization
  3. GRB 231123C: Insight-HXMT/HE detection
  4. Fermi trigger No 722460326: Global MASTER-Net observations report
  5. Fermi trigger No 722507896: Global MASTER-Net observations report
  6. GRB 231123C (short): Glowbug gamma-ray detection
  7. GRB 231124A: Glowbug gamma-ray detection
  8. GRB 231123C: Swift/BAT-GUANO detection of a short burst likely outside the coded FOV
  9. Fermi trigger No 722462310: Global MASTER-Net observations report
  10. GRB 231124A: CALET Gamma-Ray Burst Monitor detection
  11. GRB 231115A: XMM-Newton observation
  12. GRB 231124A: Fermi GBM Final Real-time Localization
  13. GRB 231123A: AstroSat CZTI detection
  14. GRB 231117A: Mondy optical observations
  15. GRB 231123C: Fermi GBM Final Real-time Localization
  16. GRB 231123B: Fermi GBM Final Real-time Localization
  17. Fermi trigger No 722400249: Global MASTER-Net observations report
  18. GRB 231118A: REM optical afterglow detection
  19. GRB 231122B: AstroSat CZTI detection
  20. GRB 231122B: CALET Gamma-Ray Burst Monitor detection
  21. GRB 231122B: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  22. GRB 231117A: Chandra afterglow detection
  23. GRB 231123A: Fermi GBM Final Real-time Localization
  24. GRB 231122B: Glowbug gamma-ray detection
  25. GRB 231117A: Continued GTC Observations
  26. Fermi trigger No 722349867: Global MASTER-Net observations report
  27. GRB 231122A: GECAM detection
  28. GRB 231122B: GECAM detection
  29. GRB 231122A: Fermi GBM Final Real-time Localization
  30. GRB 231118A: ATCA detection of radio counterpart
  31. GRB 231117A: Swift/UVOT late time observations
  32. GRB 231117A: GTC Near-Infrared Observations
  33. GRB 231117A: Swift-BAT refined analysis
  34. GRB 231118A: GRBAlpha detection
  35. LIGO/Virgo/KAGRA S231118d: Upper limits from Swift/BAT-GUANO
  36. LIGO/Virgo/KAGRA S231118an: Upper limits from Swift/BAT-GUANO
  37. LIGO/Virgo/KAGRA S231114n: Upper limits from Swift/BAT-GUANO
  38. LIGO/Virgo/KAGRA S231113bb: Upper limits from Swift/BAT-GUANO
  39. GRB 231118A: VZLUSAT-2 detection
  40. GRB 231117A: AMI-LA radio observations
  41. GRB 231118A: Swift-BAT refined analysis
  42. Konus-Wind detection of GRB 231020A
  43. GRB 231117A: LDT Confirmation of Optical Fading
  44. GRB 231117A: Wendelstein Confirmation of Fading of the Optical Afterglow
  45. GRB 231118B: CALET Gamma-Ray Burst Monitor detection
  46. GRB 231117A: CALET Gamma-Ray Burst Monitor detection
  47. 231118A: Swift-UVOT Detection
  48. GRB231117A: Swift-UVOT detection
  49. GRB 231117A : MITSuME Akeno optical afterglow candidate detection
  50. GRB 231118B: Fermi GBM observation
  51. GRB 231118A: Fermi GBM observation
  52. GRB 231120A: Fermi GBM Final Real-time Localization
  53. GRB 231117A: Swift-XRT refined Analysis
  54. GRB 231118A: Swift-XRT refined Analysis
  55. GRB 231118A: MeerLICHT afterglow detection
  56. GRB 231117A: OHP/T120 optical observations
  57. GRB 231118A: VLT/X-shooter redshift
  58. Fermi trigger No 722039659: Global MASTER-Net observations report
  59. GRB 231117A: Pan-STARRS1 follow-up confirms rapid fading
  60. GRB 231117A: MAAO 0.7-m telescope optical upper limit
  61. GRB 231117A: AKO Follow-Up Observation
  62. GRB 231117A: GECAM-C detection
  63. GRB 231118A: AstroSat CZTI detection
  64. GRB 231115A: Upper limit from CALET Gamma-Ray Burst Monitor
  65. GRB 231117A: 10 GHz VLA detection
  66. GRB 231118A: Las Cumbres optical detection
  67. GRB 231118B: BALROG localization (Fermi Trigger 722039659 / GRB 231118940)
  68. GRB 231118B: Fermi GBM Final Real-time Localization
  69. GRB 231118A: LCOGT Optical Observations
  70. GRB 231118A: MASTER OT observation
  71. GRB 231118A: Continued Skynet Observations
  72. GRB 231118A: Enhanced Swift-XRT position
  73. GRB 231117A: Kinder observations with Lulin observatory for AT 2023yba without fading in r band
  74. GRB 231118A: Swift-XRT position
  75. GRB 231118A: Skynet Optical Afterglow Discovery
  76. GRB 231117A: SOAR/Goodman imaging of the afterglow
  77. GRB 231118A: Swift detection of a burst
  78. GRB 231118A: Fermi GBM Final Real-time Localization
  79. GRB 231117A: Lowell Discovery Telescope Observations
  80. GRB 231117A: ePESSTO+ host galaxy redshift confirmation
  81. GRB 231117A: ATCA detection of a radio counterpart
  82. GRB 231117A: GRBAlpha detection
  83. GRB 231117A: Keck spectroscopy of afterglow candidate
  84. GRB 231115A: Wendelstein Optical/Infrared Observations
  85. GRB 231115A: JinShan optical upper limits
  86. GRB 231117A: GIT optical follow-up
  87. GRB 231117A: LT observations consistent with fading
  88. GRB 231117A: Keck observations indicate presence of optical afterglow in z~0.3-0.5 galaxy
  89. GRB 231117A: REM optical and NIR early-time observations
  90. GRB231117A: AGILE/MCAL analysis
  91. GRB 231117A: AKO Optical Upper Limit
  92. GRB 231117A: afterglow candidate detection from Kinder observations with Lulin observatory
  93. Swift GRB 231117A: Global MASTER-Net observations report
  94. GRB 231117A (short): Glowbug gamma-ray detection
  95. GRB 231117A: ATLAS non-detection of an optical counterpart
  96. Konus-Wind detection of GRB 231117A (short/hard)
  97. GRB 231115A : OHP/T120 optical upper limit
  98. GRB 231115A: optical observations from INAF observatories
  99. GRB 231117A : MITSuME Akeno optical upper limits
  100. GRB 231117A: AGILE detection of a bright short burst

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