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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

4714 results found.

  1. Fermi trigger No 722507896: Global MASTER-Net observations report
  2. Fermi trigger No 722462310: Global MASTER-Net observations report
  3. Fermi trigger No 722400249: Global MASTER-Net observations report
  4. GRB 231117A: CALET Gamma-Ray Burst Monitor detection
  5. LIGO/Virgo/KAGRA S231119ab: Coverage and upper limits from MAXI/GSC observations
  6. GRB 231117A: MAAO 0.7-m telescope optical upper limit
  7. GRB 231117A: GECAM-C detection
  8. GRB 231117A: GRBAlpha detection
  9. GRB 231117A: REM optical and NIR early-time observations
  10. GRB 231117A (short): Glowbug gamma-ray detection
  11. GRB 231117A: ATLAS non-detection of an optical counterpart
  12. Konus-Wind detection of GRB 231117A (short/hard)
  13. GRB 231115A: optical observations from INAF observatories
  14. GRB 231117A: AGILE detection of a bright short burst
  15. GRB 231117A: AstroSat CZTI detection of a bright short burst
  16. GRB 231117A: Swift detection of a bright short burst
  17. GRB231115A: Liverpool Telescope imaging
  18. GRB 231115A: archival HST observations
  19. Fermi GRB 231115A: Global MASTER-Net observations report
  20. GRB 231111A: GMG observation (correction)
  21. GRB 231111A: GMG observation upper limit
  22. LIGO/Virgo/KAGRA S231110g: Identification of a GW compact binary merger candidate
  23. IceCube-231103A: No candidates from the Zwicky Transient Facility
  24. Fermi trigger No 721204446: Global MASTER-Net observations report
  25. Fermi GRB 231108A: Global MASTER-Net observations report
  26. GRB 231108A: Fermi GBM Final Real-time Localization
  27. Fermi GRB 231106A: Global MASTER-Net observations report
  28. IceCube-231103A: Upper limits from a search for additional neutrino events in IceCube
  29. Fermi-LAT gamma-ray observations of IceCube-231103A
  30. Fermi GRB 231103A: Global MASTER-Net observations report
  31. GRB231104A: LCOGT Optical Upper Limits
  32. IceCube Alert 231103.39: Global MASTER-Net observations report
  33. IceCube-231103A - IceCube observation of a high-energy neutrino candidate track-like event
  34. GRB 231024A: GRANDMA observations of AT2023vuc/GOTO23baj candidate
  35. Fermi trigger No 720498201: Global MASTER-Net observations report
  36. Fermi GRB 231030B: Global MASTER-Net observations report
  37. LIGO/Virgo/KAGRA S231029ai: Global MASTER-Net observations report
  38. Fermi trigger No 720224759: Global MASTER-Net observations report
  39. IceCube Alert 231027.18: Global MASTER-Net observations report
  40. LIGO/Virgo/KAGRA S231025t: Global MASTER-Net observations report
  41. LIGO/Virgo/KAGRA S231025a: Global MASTER-Net observations report
  42. LIGO/Virgo/KAGRA S231025a: two counterpart neutrino candidates from IceCube neutrino searches
  43. IceCube-231004A: Upper limits from a search for additional neutrino events in IceCube
  44. IceCube-231004A: No significant detection in HAWC
  45. GRB 231003A is not a GRB
  46. LIGO/Virgo/KAGRA S230922g: DECam GW-MMADS candidates
  47. LIGO/Virgo/KAGRA S230922g: Identification of a GW compact binary merger candidate
  48. Fermi GBM Statement for Trigger 716527670/230916144
  49. AT2023sva: redshift from OSIRIS+/GTC of the ZTF afterglow
  50. ZTF and SEDM Observations of the Candidate Optical Afterglow AT 2023sva
  51. GRB 230911A: Fermi GBM Observation
  52. Swift GRB230916.13: Global MASTER-Net observations report
  53. GRB 230911A: Swift-XRT afterglow detection
  54. Fermi trigger No 716449174: Global MASTER-Net observations report
  55. GRB 230911A: GOTO optical counterpart candidate
  56. IPN triangulation of GRB 230911D (long)
  57. GRB 230911A: Fermi GBM Final Real-time Localization
  58. GRB 230910A: Fermi GBM Final Real-time Localization
  59. LIGO/Virgo/KAGRA S230908b: one counterpart neutrino candidate from IceCube neutrino searches
  60. GRB 230205A: LBT spectroscopy of two host galaxy candidates
  61. Fermi GRB 230906A: Global MASTER-Net observations report
  62. Fermi trigger No 715429986: Global MASTER-Net observations report
  63. Swift GRB230903.72: Global MASTER-Net observations report
  64. Fermi GRB 230827A: Global MASTER-Net observations report
  65. Trigger 1187142: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  66. Fermi trigger No 714618399: Global MASTER-Net observations report
  67. LIGO/Virgo/KAGRA S230824r: Identification of a GW compact binary merger candidate
  68. LIGO/Virgo/KAGRA S230822bm: Identification of a GW compact binary merger candidate
  69. GRB 230815A: ATCA detection of radio counterpart
  70. GRB 230818A: Tautenburg observations
  71. GRB 230818A: Bassano Bresciano Observatory optical observations
  72. GRB 230818A: KGO RC-25 optical observations
  73. GRB 230818A: Swift/UVOT Detection
  74. GRB 230818A: SAO RAS Zeiss-1000 observations
  75. Fermi GRB 230818A: Global MASTER-Net observations report
  76. GRB 230817A: AstroSat CZTI detection
  77. GRB 230815A: VLT/HAWK-I near-infrared afterglow detection
  78. GRB 230815A: SOAR/Goodman follow-up imaging
  79. GRB 230815A: Swift-BAT refined analysis
  80. GRB 230815A: Enhanced Swift-XRT position
  81. GRB 230815A: Swift detection of a burst
  82. GRB 230812B: further SAO RAS optical observations
  83. GRB 230812B: Zwicky Transient Facility Identifies Optical Afterglow Candidate of a Fermi GRB (Trigger 713559497)
  84. LAT GRB230812.79: Global MASTER-Net observations report
  85. Fermi GRB 230812B: Global MASTER-Net observations report
  86. LIGO/Virgo/KAGRA S230811n: Identification of a GW compact binary merger candidate
  87. Fermi trigger No 713136868: Global MASTER-Net observations report
  88. Fermi trigger No 713205976: Global MASTER-Net observations report
  89. LIGO/Virgo/KAGRA S230808i: Identification of a GW unmodeled transient candidate
  90. Fermi trigger No 712927418: Global MASTER-Net observations report
  91. LIGO/Virgo/KAGRA S230805x: Identification of a GW compact binary merger candidate
  92. Fermi trigger No 712798043: Global MASTER-Net observations report
  93. GRB 230803A: AstroSat CZTI detection
  94. Fermi trigger No 712718833: Global MASTER-Net observations report
  95. Fermi trigger No 712713532: Global MASTER-Net observations report
  96. Fermi trigger No 712651827: Global MASTER-Net observations report
  97. Swift GRB 230802A: Global MASTER-Net observations report
  98. LIGO/Virgo/KAGRA S230731an: Coverage and upper limits from MAXI/GSC observations
  99. GRB 230728A: LCOGT Optical Upper Limit
  100. GRB 230727A: AstroSat CZTI detection

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