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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"

32775 results found.

  1. Fermi GRB 231114A: Global MASTER-Net observations report
  2. GRB 231114A (short): Glowbug gamma-ray detection
  3. LIGO/Virgo/KAGRA S231113bw: GROWTH-India coverage and upper limits
  4. GECAM-B observation of a short burst from SGR J1555-5402
  5. LIGO/Virgo/KAGRA S231114n: Identification of a GW compact binary merger candidate
  6. LIGO/Virgo/KAGRA S231113bw: Upper limits from Fermi-GBM Observations
  7. GRB 231110A: CALET Gamma-Ray Burst Monitor detection
  8. LIGO/Virgo/KAGRA S231113bb: Updated Sky localization
  9. LIGO/Virgo/KAGRA S231113bw: Coverage and upper limits from MAXI/GSC observations
  10. LIGO/Virgo/KAGRA S231113bw: Identification of a GW compact binary merger candidate
  11. GRB 231110A: Swift-BAT refined analysis
  12. GRB231111A: MDM 2.4m Hiltner Telescope Observation
  13. GRB 231106A: Glowbug gamma-ray detection
  14. GRB 231111A: Xinglong-2.16m optical observations
  15. GRB 231110A: Swift-UVOT Upper Limits
  16. LIGO/Virgo/KAGRA S231113bb: Identification of a GW compact binary merger candidate
  17. GRB 231111A: Afterglow redshift from OSIRIS+/GTC
  18. GRB 231104A: VZLUSAT-2 detection
  19. GRB 231111A: TNG tentative redshift
  20. GRB 231110A: Glowbug gamma-ray detection
  21. GRB 231110A: AstroSat CZTI detection
  22. GRB 231111A NUTTelA-TAO / BSTI Early Measurements
  23. GRB 231111A: Leavitt Observatory optical observations
  24. GRB231111A: Optical follow-up observations with Mephisto
  25. GRB 231111A: GMG observation (correction)
  26. GRB 231111A: GMG observation upper limit
  27. GRB 231111A: Osservatorio Astronomico "Nastro Verde" optical observations with detection of an optical counterpart
  28. GRB 231110A: Terskol Zeiss-2000 optical upper limit
  29. GRB 231111A: Mondy optical observations
  30. GRB 231111A: GECAM-C detection of a long burst (correction)
  31. GRB 231110A: GECAM-B detection (correction)
  32. GRB 231111A: GECAM-C detection of a long burst
  33. GRB 231110A: GECAM detection
  34. GRB 231110A: GOTO optical upper limits
  35. GRB 231110A: SAO RAS optical observations
  36. GRB231111A: YAHPT Observations
  37. GRB231111A: GIT confirmation of the optical afterglow
  38. GRB 231111A: MASTER OT earlier detection
  39. GRB 231111A: Nanshan/HMT optical observations
  40. GRB231110A: WFST Observation and upper limits
  41. LIGO/Virgo/KAGRA S231110g: Updated Sky localization
  42. LIGO/Virgo/KAGRA S231110g: Identification of a GW compact binary merger candidate
  43. IceCube-231103A: No candidates from the Zwicky Transient Facility
  44. LIGO/Virgo/KAGRA S231108u: Updated Sky localization
  45. Fermi GRB 231108A: Global MASTER-Net observations report
  46. LIGO/Virgo/KAGRA S231108u: Identification of a GW compact binary merger candidate
  47. GRB 231106A: AstroSat CZTI detection
  48. GRB 231106A: CALET Gamma-Ray Burst Monitor detection
  49. GRB 231104A: Swift-BAT refined analysis
  50. Fermi GRB 231106A: Global MASTER-Net observations report
  51. GRB 231104A: Wendelstein Optical/Infrared Observations
  52. GRB 231104A: NuSTAR Observation of the prompt emission
  53. GRB 231104A: 3.6m DOT optical upper limit
  54. IceCube-231103A: Upper limits from a search for additional neutrino events in IceCube
  55. Fermi-LAT gamma-ray observations of IceCube-231103A
  56. GRB 231104A: NOT upper limit
  57. GRB 231104A: Fermi GBM Observation
  58. Fermi GRB 231103A: Global MASTER-Net observations report
  59. LIGO/Virgo/KAGRA S231104ac: Updated Sky localization
  60. GRB 231104A: AKO Upper Limit
  61. GRB 231104A: AstroSat CZTI detection
  62. GRB 231104A: Fermi-LAT detection
  63. LIGO/Virgo/KAGRA S231104ac: Identification of a GW compact binary merger candidate
  64. GRB 231104A: Swift/UVOT Upper Limits
  65. GRB231104A: LCOGT Optical Upper Limits
  66. Fermi-LAT gamma-ray observations of IceCube-231027A
  67. LIGO/Virgo/KAGRA S231102w: Updated Sky localization
  68. GRB 231101A: Glowbug gamma-ray detection
  69. GRB 231024A: GRANDMA observations of AT2023vuc/GOTO23baj candidate
  70. LIGO/Virgo/KAGRA S231102w: Identification of a GW compact binary merger candidate
  71. New Swift-BAT/GUANO and IceCube Notices Available via GCN Kafka
  72. GRB 231030B: GRBAlpha detection
  73. GRB 231030B: Fermi GBM Detection
  74. GRB 231030B: AstroSat CZTI detection
  75. Fermi GRB 231030B: Global MASTER-Net observations report
  76. IPN triangulation of GRB 231020A
  77. GRB 231028A: Swift-BAT refined analysis
  78. IceCube-231027A: Upper limits from a search for additional neutrino events in IceCube
  79. GRB 231024A: AKO Optical Counterpart Candidate
  80. GRB 231028A: CALET Gamma-Ray Burst Monitor detection
  81. Fermi GRB 231030A: Global MASTER-Net observations report
  82. LIGO/Virgo/KAGRA S231029y: Identification of a GW compact binary merger candidate
  83. GRID detection of GRB 231020A
  84. GRB 231028A: AstroSat CZTI detection
  85. GRB 231028A: Glowbug gamma-ray detection
  86. GRB 231028A: Fermi GBM Detection
  87. Swift GRB 231028A: Global MASTER-Net observations report
  88. LIGO/Virgo/KAGRA S231028bg: Updated Sky localization
  89. LIGO/Virgo/KAGRA S231028bg: Identification of a GW compact binary merger candidate
  90. GRB 231028A: Swift detection of a burst
  91. GRB 231019A: Glowbug gamma-ray detection
  92. IC231004A: GRANDMA observations of AT2023uqf/ZTF23abidzvf candidate
  93. GRB 231025A: Fermi GBM Observation
  94. GRB 231024A: Fermi GBM Observation
  95. GRB 231025A: Swift/BAT-GUANO detection of a likely short burst
  96. GRB 231024A: X-shooter spectroscopy of AT2023vuc/GOTO23baj reveals a young supernova with flash ionisation features
  97. GRB 231024A: LCOGT and ZTF detections of the GOTO optical counterpart candidate
  98. GRB 231020A: AstroSat CZTI detection
  99. GRB 231020B: AstroSat CZTI detection
  100. GRB 231024A: GOTO optical counterpart candidate

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