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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"

37789 results found.

  1. GRB 231117A : MITSuME Akeno optical upper limits
  2. GRB 231117A: AGILE detection of a bright short burst
  3. GRB 231117A: Enhanced Swift-XRT position
  4. GRB 231117A: GOTO optical upper limits
  5. GRB 231117A: AstroSat CZTI detection of a bright short burst
  6. GRB 231117A: Swift detection of a bright short burst
  7. GRB 231115A: Non-detection of radio emission with CHIME/FRB
  8. GRB 231111A: Swift/UVOT Detection
  9. MAGIC observation of GRB 231115A, a possible magnetar giant flare
  10. GRB231115A: Liverpool Telescope imaging
  11. GRB 231115A: NuSTAR Follow-Up Observations
  12. GRB 231115A: Swift/BAT-GUANO detection of a short burst
  13. GRB 231115A: Swift-XRT and Swift-UVOT observations
  14. Fermi GRB 231116A: Global MASTER-Net observations report
  15. Konus-Wind detection of GRB 231115A (a probable Magnetar Giant Flare from M82)
  16. GRB 231115A: AGILE/MCAL upper limits
  17. GRB 231115A: Insight-HXMT/HE detection
  18. GRB 231115A: GBM/Fermi Observations of a probable Giant Flare of Magnetar
  19. GRB 231116A: Fermi GBM Final Real-time Localization
  20. GRB 231115A : MITSuME Akeno and Okayama optical upper limits
  21. GRB 231115A: Gaoyazi/GOT follow-up and archival observations
  22. GRB 231115A / AT2023xvj: Updated GIT analysis
  23. GRB 231115A: archival Chandra X-ray observations
  24. GRB 231115A: Upper limits from a neutrino search with IceCube
  25. GRB 231115A: Kinder observations with Lulin observatory
  26. GRB231115A: GRANDMA Observations
  27. GRB 231115A: GOTO pre-burst limits of AT2023xvj
  28. GRB 231115A: Non-detection in low-latency of gravitational waves with LIGO/Virgo/KAGRA
  29. GRB 231115A: pre-burst ZTF upper limits for GRB optical counterpart candidate
  30. GRB 231106A: TESS identification of candidate optical counterpart
  31. GRB 231115A: MASTER optical observations
  32. GRB 231115A (short): Glowbug gamma-ray detection
  33. GRB 231115A: Fermi Observations of a probable Magnetar Giant Flare from M82
  34. GRB 231115A: archival HST observations
  35. GRB 231115A: GROWTH-India discovery of a potential optical counterpart
  36. GRB 231115A: Swift ToO observations
  37. Fermi GRB 231115A: Global MASTER-Net observations report
  38. GRB 231115A: significance of INTEGRAL localization alignment with M82
  39. GRB 231115A: a short hard GRB detected by IBAS, poistionally coincident with M82
  40. GRB 231115A position consistent with M 82 galaxy
  41. GRB 231115A: Fermi GBM Final Real-time Localization
  42. GRB 231111A: Swift-BAT refined analysis
  43. Fermi GRB 231114A: Global MASTER-Net observations report
  44. GRB 231113A (short): Glowbug gamma-ray detection
  45. GRB 231114A (short): Glowbug gamma-ray detection
  46. GECAM-B observation of a short burst from SGR J1555-5402
  47. GRB 231114A: Fermi GBM Final Localization
  48. SGRJ1555-5402: Swift/BAT-GUANO arcminute localization of a SGR flare
  49. LIGO/Virgo/KAGRA S231113bw: Upper limits from Fermi-GBM Observations
  50. GRB 231110A: CALET Gamma-Ray Burst Monitor detection
  51. GRB 231110A: Swift-BAT refined analysis
  52. GRB231111A: MDM 2.4m Hiltner Telescope Observation
  53. GRB 231106A: Glowbug gamma-ray detection
  54. GRB 231111A: Xinglong-2.16m optical observations
  55. GRB 231110A: Swift-UVOT Upper Limits
  56. GRB 231111A: Afterglow redshift from OSIRIS+/GTC
  57. GRB 231104A: VZLUSAT-2 detection
  58. GRB 231111A: TNG tentative redshift
  59. GRB 231110A: Glowbug gamma-ray detection
  60. GRB 231110A: AstroSat CZTI detection
  61. GRB 231111A NUTTelA-TAO / BSTI Early Measurements
  62. GRB 231111A: Leavitt Observatory optical observations
  63. GRB231111A: Optical follow-up observations with Mephisto
  64. GRB 231111A: GMG observation (correction)
  65. GRB 231111A: GMG observation upper limit
  66. GRB 231106B: GRBAlpha detection
  67. GRB 231111A: Osservatorio Astronomico "Nastro Verde" optical observations with detection of an optical counterpart
  68. GRB 231110A: Terskol Zeiss-2000 optical upper limit
  69. GRB 231111A: Swift-XRT refined Analysis
  70. GRB 231111A: Mondy optical observations
  71. GRB 231111A: GECAM-C detection of a long burst (correction)
  72. GRB 231110A: GECAM-B detection (correction)
  73. GRB 231111A: Enhanced Swift-XRT position
  74. GRB 231111A: GECAM-C detection of a long burst
  75. GRB 231110A: GECAM detection
  76. GRB 231110A: GOTO optical upper limits
  77. GRB 231110A: SAO RAS optical observations
  78. GRB 231110A: Swift-XRT afterglow detection
  79. GRB231111A: YAHPT Observations
  80. GRB231111A: GIT confirmation of the optical afterglow
  81. GRB 231111A: MASTER OT earlier detection
  82. GRB 231111A: Nanshan/HMT optical observations
  83. GRB 231111A: Swift detection of a burst with an optical counterpart
  84. GRB231110A: WFST Observation and upper limits
  85. GRB 231110A: Swift detection of a burst
  86. GRB 231109A: Fermi GBM Final Localization
  87. Fermi trigger No 721204446: Global MASTER-Net observations report
  88. Fermi GRB 231108A: Global MASTER-Net observations report
  89. GRB 231108A: Fermi GBM Final Real-time Localization
  90. GRB 231106A: AstroSat CZTI detection
  91. GRB 231106A: CALET Gamma-Ray Burst Monitor detection
  92. GRB 231104A: Swift-BAT refined analysis
  93. Fermi trigger No 721006392: Global MASTER-Net observations report
  94. Fermi Gamma-ray Burst Monitor trigger 231107654 / 721064512 is not a GRB
  95. GRB 231104A: FRAM-ORM optical limit
  96. LIGO/Virgo/KAGRA S231102w: Upper limits from Swift/BAT-GUANO
  97. Fermi GRB 231106A: Global MASTER-Net observations report
  98. GRB 231104A: Wendelstein Optical/Infrared Observations
  99. GRB 231104A: NuSTAR Observation of the prompt emission
  100. GRB 231106A: Fermi GBM Final Real-time Localization

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