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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').
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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"

45684 results found.

  1. GRB 251023B / EP251023b: COLIBRÍ Confirmation of the Fading Nature of the Optical Candidate
  2. GRB 251022A: COLIBRÍ Further Multi-frequency Optical Observations
  3. EP251023a: MAO/AZT-22 optical observations
  4. GRB 251023B: OHP/T193 optical observations
  5. EP251023a: OHP/T193 optical observations
  6. GRB 251023C: AstroSat CZTI detection
  7. EP251023b/GRB 251023B: JinShan optical observation
  8. GRB 251022A: Swift-XRT detection of GOTO25iym
  9. EP251023b: Global MASTER-Net observations report
  10. EP251023b/GRB 251023B : Einstein Probe detection of a fast X-ray transient
  11. GRB 251023C: CALET Gamma-Ray Burst Monitor detection
  12. GRB 251022A: GROWTH-India Telescope optical observations
  13. GRB 251023C: Swift/BAT-GUANO localization skymap of a burst
  14. EP251023a: GROWTH-India Telescope optical observations
  15. GRB 251022A: Fermi GBM Observation
  16. GRB 251022A: Swift/BAT-GUANO localization skymap of a burst
  17. GRB 251023A: Glowbug gamma-ray detection
  18. GRB 251023B: Glowbug gamma-ray detection
  19. EP251023a: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 40-cm telescope at Teide Observatory
  20. EP251023a: Global MASTER-Net observations report
  21. GRB 251023B / EP#01709247298: COLIBRÍ optical counterpart candidate
  22. IPN triangulation of GRB 251016B
  23. GRB 251023B: CALET Gamma-Ray Burst Monitor detection
  24. EP#01709247298: Swift-XRT counterpart detection
  25. EP251023a: COLIBRÍ optical observations
  26. GRB 251013C: further SAO RAS optical observations
  27. EP251023a: Keck/LRIS spectroscopic redshift z=2.232
  28. GRB 251022A: COLIBRÍ optical observations
  29. GRB 251013C: ISON-Castelgrande observatory optical observations
  30. GRB 251022A: MASTER OT detection
  31. GRB 251022A: DDOTI Optical Detection
  32. EP251021b/GRB 251021A: SVOM/VT optical candidate
  33. GRB 251023B / MAXI J0451+122: MAXI/GSC detection
  34. EP251023a: NOT optical counterpart detection
  35. Fermi GRB 251023A: Global MASTER-Net observations report
  36. EP251023a: GSP Optical Counterpart Detection
  37. EP251023a: Einstein Probe detection of an X-ray transient
  38. EP/WXT 01709247295: GOTO optical afterglow candidate.
  39. GRB 251022A: GOTO optical counterpart detection
  40. GRB 251023A: Fermi GBM Final Localization Correction
  41. GRB 251022A: Fermi-LAT detection
  42. GRB 251016B: Fermi GBM Detection
  43. GRB 251022A: Tiled Swift observations
  44. LAT GRB251022A: Global MASTER-Net observations report
  45. GRB 251022A: Fermi GBM Final Real-time Localization
  46. GRB 251021A/EP251021b: Fermi-GBM Sub-Threshold Detection
  47. EP251021b: BOOTES-7 optical upper limit
  48. EP251021b: Einstein Probe detection of a fast X-ray transient
  49. GRB 250911A: MAXI/GSC detection
  50. LIGO/Virgo/KAGRA S251021u: Updated Sky localization
  51. GRB 251016A: SVOM/ECLAIRs refined analysis
  52. LIGO/Virgo/KAGRA S251021u: Identification of a GW compact binary merger candidate
  53. LIGO/Virgo/KAGRA S251018bi: Updated Sky localization
  54. Fermi-LAT gamma-ray observations of IceCube-251018A
  55. GRB 251017A : RAPAS follow-up observations
  56. IceCube-251018A: Upper limits from a search for additional neutrino events in IceCube
  57. GRB 251017A: COLIBRÍ optical observations of a late plateau
  58. IceCube-251018A: DDOTI Optical Upper Limit
  59. GRB 251017A: Swift-BAT refined analysis
  60. GRB 251016A: Fermi GBM Observation
  61. GRB 251018A: Fermi GBM Observation
  62. GRB 251018A: BOOTES-5 and BOOTES-7 early optical detections
  63. GRB 251018A: Swift-XRT refined Analysis
  64. GRB 251018A: Enhanced Swift-XRT position
  65. Fermi trigger No 782500909: Global MASTER-Net observations report
  66. GRB 251016A: HXMT/HE detection
  67. IceCube-251018A: Global MASTER-Net observations report
  68. LIGO/Virgo/KAGRA S251018bi: Identification of a GW compact binary merger candidate
  69. GRB 251016A: Swift-XRT afterglow detection
  70. GRB 251017A: Swift/UVOT Detection
  71. GRB 251016A: Swift/UVOT Detection
  72. GRB 251018A: Swift/UVOT Detection
  73. IceCube-251018A - IceCube observation of a high-energy neutrino candidate track-like event
  74. IceCube-251018A - IceCube observation of a high-energy neutrino candidate track-like event (duplicate submission)
  75. GRB 251017A: VLT/MUSE spectroscopic redshift z = 4.327
  76. GRB 251016A: VLT/FORS2 Optical Observation
  77. GRB 251017A: COLIBRÍ photometric redshift
  78. GRB 251017A: Swift-XRT refined Analysis
  79. GRB 251018A: MASTER OT detection
  80. GRB 251018A: TRT optical afterglow detection
  81. Swift GRB 251018A: Global MASTER-Net observations report
  82. GRB 251018A: Swift detection of a burst with an optical counterpart
  83. GRB 251018A: Fermi GBM Final Real-time Localization
  84. GRB 251017A: SVOM/VT optical observation
  85. GRB 251011A: Fermi GBM Observation
  86. GRB 251017A: OHP/T193 i-band observations
  87. GRB 251013C: OHP/T193 third epoch optical observations and detected rebrightening
  88. LIGO/Virgo/KAGRA S251017di: Retraction of GW compact binary merger candidate
  89. GRB 251017A: J-band detection with WINTER
  90. GRB 251017A: Glowbug gamma-ray detection
  91. GRB 251013C: Liverpool Telescope observations
  92. GRB 251013C: Leavitt Observatory optical photometry
  93. Fermi GRB 251016B: Global MASTER-Net observations report
  94. GRB 251017A: JinShan observations of the optical afterglow
  95. Swift GRB 251017A: Global MASTER-Net observations report
  96. GRB 251017A : MITSuME Akeno optical afterglow candidate detection
  97. Swift Trigger 1404295 is not a GRB
  98. GRB 251016A: AstroSat CZTI detection of a short burst
  99. GRB 251017A: Enhanced Swift-XRT position
  100. GRB 251017A: COLIBRÍ Early Afterglow Detection

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