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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"

32568 results found.

  1. EP251023a: OHP/T193 optical observations
  2. GRB 251023C: AstroSat CZTI detection
  3. EP251023b/GRB 251023B: JinShan optical observation
  4. GRB 251022A: Swift-XRT detection of GOTO25iym
  5. EP251023b: Global MASTER-Net observations report
  6. EP251023b/GRB 251023B : Einstein Probe detection of a fast X-ray transient
  7. GRB 251023C: CALET Gamma-Ray Burst Monitor detection
  8. GRB 251022A: GROWTH-India Telescope optical observations
  9. EP251023a: GROWTH-India Telescope optical observations
  10. GRB 251022A: Fermi GBM Observation
  11. GRB 251022A: Swift/BAT-GUANO localization skymap of a burst
  12. GRB 251023A: Glowbug gamma-ray detection
  13. GRB 251023B: Glowbug gamma-ray detection
  14. EP251023a: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 40-cm telescope at Teide Observatory
  15. EP251023a: Global MASTER-Net observations report
  16. GRB 251023B / EP#01709247298: COLIBRÍ optical counterpart candidate
  17. IPN triangulation of GRB 251016B
  18. GRB 251023B: CALET Gamma-Ray Burst Monitor detection
  19. EP#01709247298: Swift-XRT counterpart detection
  20. EP251023a: COLIBRÍ optical observations
  21. GRB 251013C: further SAO RAS optical observations
  22. EP251023a: Keck/LRIS spectroscopic redshift z=2.232
  23. GRB 251022A: COLIBRÍ optical observations
  24. GRB 251013C: ISON-Castelgrande observatory optical observations
  25. GRB 251022A: MASTER OT detection
  26. GRB 251022A: DDOTI Optical Detection
  27. EP251021b/GRB 251021A: SVOM/VT optical candidate
  28. EP251023a: NOT optical counterpart detection
  29. Fermi GRB 251023A: Global MASTER-Net observations report
  30. EP251023a: GSP Optical Counterpart Detection
  31. EP251023a: Einstein Probe detection of an X-ray transient
  32. GRB 251022A: GOTO optical counterpart detection
  33. GRB 251022A: Fermi-LAT detection
  34. GRB 251022A: Tiled Swift observations
  35. GRB 251021A/EP251021b: Fermi-GBM Sub-Threshold Detection
  36. EP251021b: BOOTES-7 optical upper limit
  37. GRB 250911A: MAXI/GSC detection
  38. LIGO/Virgo/KAGRA S251021u: Updated Sky localization
  39. GRB 251016A: SVOM/ECLAIRs refined analysis
  40. LIGO/Virgo/KAGRA S251021u: Identification of a GW compact binary merger candidate
  41. LIGO/Virgo/KAGRA S251018bi: Updated Sky localization
  42. Fermi-LAT gamma-ray observations of IceCube-251018A
  43. GRB 251017A : RAPAS follow-up observations
  44. IceCube-251018A: Upper limits from a search for additional neutrino events in IceCube
  45. GRB 251017A: COLIBRÍ optical observations of a late plateau
  46. IceCube-251018A: DDOTI Optical Upper Limit
  47. GRB 251017A: Swift-BAT refined analysis
  48. GRB 251016A: Fermi GBM Observation
  49. GRB 251018A: Fermi GBM Observation
  50. GRB 251018A: BOOTES-5 and BOOTES-7 early optical detections
  51. GRB 251016A: HXMT/HE detection
  52. LIGO/Virgo/KAGRA S251018bi: Identification of a GW compact binary merger candidate
  53. GRB 251017A: Swift/UVOT Detection
  54. GRB 251016A: Swift/UVOT Detection
  55. GRB 251018A: Swift/UVOT Detection
  56. IceCube-251018A - IceCube observation of a high-energy neutrino candidate track-like event (duplicate submission)
  57. GRB 251017A: VLT/MUSE spectroscopic redshift z = 4.327
  58. GRB 251016A: VLT/FORS2 Optical Observation
  59. GRB 251017A: COLIBRÍ photometric redshift
  60. GRB 251018A: MASTER OT detection
  61. GRB 251018A: TRT optical afterglow detection
  62. Swift GRB 251018A: Global MASTER-Net observations report
  63. GRB 251017A: SVOM/VT optical observation
  64. GRB 251011A: Fermi GBM Observation
  65. GRB 251017A: OHP/T193 i-band observations
  66. GRB 251013C: OHP/T193 third epoch optical observations and detected rebrightening
  67. GRB 251017A: J-band detection with WINTER
  68. GRB 251017A: Glowbug gamma-ray detection
  69. GRB 251013C: Liverpool Telescope observations
  70. GRB 251013C: Leavitt Observatory optical photometry
  71. Fermi GRB 251016B: Global MASTER-Net observations report
  72. GRB 251017A: JinShan observations of the optical afterglow
  73. Swift GRB 251017A: Global MASTER-Net observations report
  74. GRB 251017A : MITSuME Akeno optical afterglow candidate detection
  75. Swift Trigger 1404295 is not a GRB
  76. GRB 251016A: AstroSat CZTI detection of a short burst
  77. GRB 251017A: COLIBRÍ Early Afterglow Detection
  78. GRB 251016B: AstroSat CZTI detection
  79. GRB 251017A: BOOTES-5/JGT early optical afterglow detection
  80. GRB 251016A: CALET Gamma-Ray Burst Monitor detection
  81. GRB 251016B: CALET Gamma-Ray Burst Monitor detection
  82. GRB 251013C: JinShan observations of the non-thermal rebrightening of the optical counterpart
  83. GRB 251013C: SVOM/COLIBRÍ (FM-GFT) observations of a strong and late rebrightening of the optical counterpart
  84. GRB 251007B: Swift-BAT refined analysis
  85. GRB 251014D: Swift-BAT refined analysis
  86. GRB 251016A: BOOTES-6/DPRT optical upper limit
  87. GRB 251016A: Glowbug gamma-ray detection of a short burst
  88. GRB 251013C: VLA detection
  89. Fermi GRB 251016A: Global MASTER-Net observations report
  90. LIGO/Virgo/KAGRA S251014cn: Updated Sky localization
  91. GRB 251014B: PRIME J-band upper limit
  92. Upper limits from a search for additional neutrino events in IceCube
  93. GRB 251013C: Kilonova-Catcher optical afterglow detection
  94. Fermi-LAT Gamma-ray Observations of IceCube-251014A
  95. GRB 251013D: Swift/UVOT Observations
  96. GRB 251013C: Swift/UVOT Detection
  97. Konus-Wind detection of GRB 251007A
  98. GRB 251013C, GCN Circular 42267, errata corrige
  99. GRB 251013C: detection of a radio counterpart at 15.5GHz
  100. GRB 251013C: SVOM/ECLAIRs refined analysis

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