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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"

37363 results found.

  1. GRB 231115A / AT2023xvj: Updated GIT analysis
  2. GRB 231115A: archival Chandra X-ray observations
  3. GRB 231115A: Upper limits from a neutrino search with IceCube
  4. GRB 231115A: Kinder observations with Lulin observatory
  5. GRB231115A: GRANDMA Observations
  6. GRB 231115A: GOTO pre-burst limits of AT2023xvj
  7. GRB 231115A: Non-detection in low-latency of gravitational waves with LIGO/Virgo/KAGRA
  8. GRB 231115A: pre-burst ZTF upper limits for GRB optical counterpart candidate
  9. GRB 231106A: TESS identification of candidate optical counterpart
  10. GRB 231115A: MASTER optical observations
  11. GRB 231115A (short): Glowbug gamma-ray detection
  12. GRB 231115A: Fermi Observations of a probable Magnetar Giant Flare from M82
  13. GRB 231115A: archival HST observations
  14. GRB 231115A: GROWTH-India discovery of a potential optical counterpart
  15. GRB 231115A: Swift ToO observations
  16. Fermi GRB 231115A: Global MASTER-Net observations report
  17. GRB 231115A: significance of INTEGRAL localization alignment with M82
  18. GRB 231115A: a short hard GRB detected by IBAS, poistionally coincident with M82
  19. GRB 231115A position consistent with M 82 galaxy
  20. GRB 231115A: Fermi GBM Final Real-time Localization
  21. GRB 231111A: Swift-BAT refined analysis
  22. Fermi GRB 231114A: Global MASTER-Net observations report
  23. GRB 231113A (short): Glowbug gamma-ray detection
  24. GRB 231114A (short): Glowbug gamma-ray detection
  25. GRB 231114A: Fermi GBM Final Localization
  26. SGRJ1555-5402: Swift/BAT-GUANO arcminute localization of a SGR flare
  27. LIGO/Virgo/KAGRA S231113bw: Upper limits from Fermi-GBM Observations
  28. GRB 231110A: CALET Gamma-Ray Burst Monitor detection
  29. LIGO/Virgo/KAGRA S231113cd: Coverage and upper limits from MAXI/GSC observations
  30. LIGO/Virgo/KAGRA S231113bw: Coverage and upper limits from MAXI/GSC observations
  31. GRB 231110A: Swift-BAT refined analysis
  32. GRB231111A: MDM 2.4m Hiltner Telescope Observation
  33. GRB 231106A: Glowbug gamma-ray detection
  34. GRB 231111A: Xinglong-2.16m optical observations
  35. GRB 231110A: Swift-UVOT Upper Limits
  36. GRB 231111A: Afterglow redshift from OSIRIS+/GTC
  37. GRB 231104A: VZLUSAT-2 detection
  38. GRB 231111A: TNG tentative redshift
  39. GRB 231110A: Glowbug gamma-ray detection
  40. GRB 231110A: AstroSat CZTI detection
  41. GRB 231111A NUTTelA-TAO / BSTI Early Measurements
  42. GRB 231111A: Leavitt Observatory optical observations
  43. GRB231111A: Optical follow-up observations with Mephisto
  44. GRB 231111A: GMG observation (correction)
  45. GRB 231111A: GMG observation upper limit
  46. GRB 231106B: GRBAlpha detection
  47. GRB 231111A: Osservatorio Astronomico "Nastro Verde" optical observations with detection of an optical counterpart
  48. GRB 231110A: Terskol Zeiss-2000 optical upper limit
  49. GRB 231111A: Swift-XRT refined Analysis
  50. GRB 231111A: Mondy optical observations
  51. GRB 231111A: GECAM-C detection of a long burst (correction)
  52. GRB 231110A: GECAM-B detection (correction)
  53. GRB 231111A: Enhanced Swift-XRT position
  54. GRB 231111A: GECAM-C detection of a long burst
  55. GRB 231110A: GECAM detection
  56. GRB 231110A: GOTO optical upper limits
  57. GRB 231110A: SAO RAS optical observations
  58. GRB 231110A: Swift-XRT afterglow detection
  59. GRB231111A: YAHPT Observations
  60. GRB231111A: GIT confirmation of the optical afterglow
  61. GRB 231111A: MASTER OT earlier detection
  62. GRB 231111A: Nanshan/HMT optical observations
  63. GRB 231111A: Swift detection of a burst with an optical counterpart
  64. GRB231110A: WFST Observation and upper limits
  65. GRB 231110A: Swift detection of a burst
  66. GRB 231109A: Fermi GBM Final Localization
  67. IceCube-231103A: No candidates from the Zwicky Transient Facility
  68. Fermi GRB 231108A: Global MASTER-Net observations report
  69. GRB 231108A: Fermi GBM Final Real-time Localization
  70. LIGO/Virgo/KAGRA O4 Landscape
  71. GRB 231106A: AstroSat CZTI detection
  72. GRB 231106A: CALET Gamma-Ray Burst Monitor detection
  73. GRB 231104A: Swift-BAT refined analysis
  74. Fermi Gamma-ray Burst Monitor trigger 231107654 / 721064512 is not a GRB
  75. GRB 231104A: FRAM-ORM optical limit
  76. LIGO/Virgo/KAGRA S231102w: Upper limits from Swift/BAT-GUANO
  77. Fermi GRB 231106A: Global MASTER-Net observations report
  78. GRB 231104A: Wendelstein Optical/Infrared Observations
  79. GRB 231104A: NuSTAR Observation of the prompt emission
  80. GRB 231106A: Fermi GBM Final Real-time Localization
  81. GRB 231104A: 3.6m DOT optical upper limit
  82. GRB 231104A: NOT upper limit
  83. GRB 231104A: Fermi GBM Observation
  84. GRB 231104B: Fermi GBM Final Real-time Localization
  85. Fermi GRB 231103A: Global MASTER-Net observations report
  86. GRB 231104A: AKO Upper Limit
  87. GRB 231104A: AstroSat CZTI detection
  88. GRB 231104A: Swift-XRT refined Analysis
  89. GRB 231104A: Fermi-LAT detection
  90. GRB 231104A: Swift/UVOT Upper Limits
  91. GRB 231104A: Enhanced Swift-XRT position
  92. GRB231104A: LCOGT Optical Upper Limits
  93. GRB 231104A: Swift detection of a bright burst
  94. GRB 231104A: Fermi GBM Final Real-time Localization
  95. GRB 231103A: Fermi GBM Final Real-time Localization
  96. GRB 231101A: Glowbug gamma-ray detection
  97. GRB 231024A: GRANDMA observations of AT2023vuc/GOTO23baj candidate
  98. GRB 231101A: Fermi GBM Final Real-time Localization
  99. GRB 231030B: GRBAlpha detection
  100. GRB 231028B: VZLUSAT-2 detection

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