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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"

20519 results found.

  1. GRB 251013C: further SAO RAS optical observations
  2. GRB 251022A: COLIBRÍ optical observations
  3. GRB 251013C: ISON-Castelgrande observatory optical observations
  4. GRB 251022A: MASTER OT detection
  5. GRB 251022A: DDOTI Optical Detection
  6. EP251021b/GRB 251021A: SVOM/VT optical candidate
  7. EP251023a: NOT optical counterpart detection
  8. EP251023a: Einstein Probe detection of an X-ray transient
  9. EP251021b: Einstein Probe detection of a fast X-ray transient
  10. GRB 250911A: MAXI/GSC detection
  11. GRB 251016A: SVOM/ECLAIRs refined analysis
  12. LIGO/Virgo/KAGRA S251021u: Identification of a GW compact binary merger candidate
  13. Fermi-LAT gamma-ray observations of IceCube-251018A
  14. GRB 251017A : RAPAS follow-up observations
  15. IceCube-251018A: Upper limits from a search for additional neutrino events in IceCube
  16. GRB 251017A: COLIBRÍ optical observations of a late plateau
  17. IceCube-251018A: DDOTI Optical Upper Limit
  18. GRB 251018A: Enhanced Swift-XRT position
  19. LIGO/Virgo/KAGRA S251018bi: Identification of a GW compact binary merger candidate
  20. GRB 251016A: Swift-XRT afterglow detection
  21. GRB 251017A: Swift/UVOT Detection
  22. GRB 251016A: Swift/UVOT Detection
  23. GRB 251018A: Swift/UVOT Detection
  24. GRB 251016A: VLT/FORS2 Optical Observation
  25. GRB 251017A: COLIBRÍ photometric redshift
  26. GRB 251018A: MASTER OT detection
  27. GRB 251018A: TRT optical afterglow detection
  28. GRB 251018A: Swift detection of a burst with an optical counterpart
  29. GRB 251017A: SVOM/VT optical observation
  30. GRB 251013C: OHP/T193 third epoch optical observations and detected rebrightening
  31. GRB 251017A: J-band detection with WINTER
  32. GRB 251013C: Liverpool Telescope observations
  33. GRB 251013C: Leavitt Observatory optical photometry
  34. GRB 251017A: JinShan observations of the optical afterglow
  35. GRB 251017A : MITSuME Akeno optical afterglow candidate detection
  36. GRB 251017A: Enhanced Swift-XRT position
  37. GRB 251017A: COLIBRÍ Early Afterglow Detection
  38. GRB 251017A: Swift detection of a burst with an optical counterpart
  39. GRB 251013C: JinShan observations of the non-thermal rebrightening of the optical counterpart
  40. GRB 251013C: SVOM/COLIBRÍ (FM-GFT) observations of a strong and late rebrightening of the optical counterpart
  41. sb25101602: Swift-XRT counterpart detection
  42. GRB 251014B: PRIME J-band upper limit
  43. Upper limits from a search for additional neutrino events in IceCube
  44. Swift GRB251015.60: Global MASTER-Net observations report
  45. GRB 251013C: Kilonova-Catcher optical afterglow detection
  46. Fermi-LAT Gamma-ray Observations of IceCube-251014A
  47. GRB 251013D: Swift/UVOT Observations
  48. GRB 251013C: Swift/UVOT Detection
  49. Konus-Wind detection of GRB 251007A
  50. GRB 251013C: detection of a radio counterpart at 15.5GHz
  51. GRB 251013C: SVOM/ECLAIRs refined analysis
  52. Swift Trigger 1404295: possible GRB 251015A
  53. GRB 251014B: Swift-XRT observations
  54. GRB 251014B: Swift/UVOT Upper Limits
  55. GRB 251014B: VLT/FORS2 Optical Observation
  56. GRB 251014D: Swift/UVOT Upper Limits
  57. GRB 251014D: Swift-XRT afterglow detection
  58. GRB 251013C: MAO/AZT-22 optical observations
  59. GRB 251011B: SVOM/VT optical upper limit
  60. GRB 251013C: SVOM/COLIBRÍ (FM-GFT) further multi-band optical observations
  61. GRB 251013C: Calapai Observatory, Massa S. Giorgio (Messina), optical observation
  62. GRB 251014D: Swift detection of a burst
  63. GRB 251014A: PRIME near-infrared upper limits
  64. GRB 251014A: VLT/FORS2 Optical Observation
  65. GRB 251013C: MarSEC, optical afterglow photometry
  66. GRB 251013C: OHP/T193 optical afterglow photometry and spectroscopy
  67. GRB 251013D: LAST optical upper limit on Swift/BAT-GUANO localization
  68. GRB 251013C: Bassano Bresciano Observatory optical observations
  69. GRB 251013C: Early and late-time optical counterpart detection by LCO
  70. GRB 251014A: DDOTI Upper Limit
  71. GRB 251013C NUTTelA-TAO / BSTI Early Measurements
  72. LIGO/Virgo/KAGRA S251014cn: Identification of a GW compact binary merger candidate
  73. GRB 251013C: ULL-ASTRO-MASTER detection of the optical afterglow with the LCO 40-cm telescope at Sutherland Observatory
  74. GRB 251013C: Asiago optical observations
  75. GRB 251013C: ABObservatory optical observations
  76. GRB 251014A: SAO RAS optical upper limit
  77. GRB 251013C: J band observations by SYSU 80cm infrared telescope
  78. GRB 251013C: SVOM/COLIBRÍ (FM-GFT) detection of the optical counterpart
  79. GRB 251013C: DDOTI detection of the optical afterglow
  80. GRB 251013C: SAO RAS optical observations
  81. GRB 251013C: LCO optical afterglow detection
  82. GRB 251013C: NOT spectroscopic redshift z = 0.572
  83. GRB 251013C: LAST detection of optical counterpart
  84. GRB 251013C: SVOM/VT optical observation
  85. GRB 251013C: SVOM detection of a burst
  86. GRB 251013B: SVOM/GRM observation
  87. GRB 251013A: SVOM/GRM observation
  88. GRB 251003A: Mondy optical upper limit
  89. MASTER OT J011025.98-583210.6 : SVOM/VT optical observation
  90. LIGO/Virgo/KAGRA S251013x: Identification of a GW compact binary merger candidate
  91. GRB 251011B inspection: MASTER orphan GRB detection
  92. GRB 251011B: Swift/UVOT Upper Limits
  93. GRB 251011B: SVOM/GRM observation
  94. GRB 251011B : MASTER optical observations
  95. GRB 251011B: Enhanced Swift-XRT position
  96. GRB 251010A: AstroSat CZTI detection
  97. GRB 251011B: Swift detection of a burst
  98. GRB 251007B: Swift/UVOT Upper Limits
  99. GRB251007A: Swift/UVOT Detection
  100. GRB 251007A: SVOM/GRM observation

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