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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"

32795 results found.

  1. GRB 231115A: Upper limits from a neutrino search with IceCube
  2. GRB 231115A: Kinder observations with Lulin observatory
  3. GRB231115A: GRANDMA Observations
  4. GRB 231115A: GOTO pre-burst limits of AT2023xvj
  5. GRB 231115A: Non-detection in low-latency of gravitational waves with LIGO/Virgo/KAGRA
  6. GRB 231115A: pre-burst ZTF upper limits for GRB optical counterpart candidate
  7. GRB 231106A: TESS identification of candidate optical counterpart
  8. GRB 231115A: MASTER optical observations
  9. GRB 231115A (short): Glowbug gamma-ray detection
  10. GRB 231115A: Fermi Observations of a probable Magnetar Giant Flare from M82
  11. GRB 231115A: archival HST observations
  12. GRB 231115A: GROWTH-India discovery of a potential optical counterpart
  13. GRB 231115A: Swift ToO observations
  14. Fermi GRB 231115A: Global MASTER-Net observations report
  15. GRB 231115A: significance of INTEGRAL localization alignment with M82
  16. GRB 231115A position consistent with M 82 galaxy
  17. LIGO/Virgo/KAGRA S231113bw: Updated Sky localization, EM Bright Classification, and Source Classification
  18. GRB 231111A: Swift-BAT refined analysis
  19. LIGO/Virgo/KAGRA S231113bw: Zwicky Transient Facility observations
  20. LIGO/Virgo/KAGRA S231114n: Updated Sky localization
  21. Fermi GRB 231114A: Global MASTER-Net observations report
  22. GRB 231114A (short): Glowbug gamma-ray detection
  23. LIGO/Virgo/KAGRA S231113bw: GROWTH-India coverage and upper limits
  24. GECAM-B observation of a short burst from SGR J1555-5402
  25. LIGO/Virgo/KAGRA S231114n: Identification of a GW compact binary merger candidate
  26. LIGO/Virgo/KAGRA S231113bw: Upper limits from Fermi-GBM Observations
  27. GRB 231110A: CALET Gamma-Ray Burst Monitor detection
  28. LIGO/Virgo/KAGRA S231113bb: Updated Sky localization
  29. LIGO/Virgo/KAGRA S231113bw: Coverage and upper limits from MAXI/GSC observations
  30. LIGO/Virgo/KAGRA S231113bw: Identification of a GW compact binary merger candidate
  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. LIGO/Virgo/KAGRA S231113bb: Identification of a GW compact binary merger candidate
  37. GRB 231111A: Afterglow redshift from OSIRIS+/GTC
  38. GRB 231104A: VZLUSAT-2 detection
  39. GRB 231111A: TNG tentative redshift
  40. GRB 231110A: Glowbug gamma-ray detection
  41. GRB 231110A: AstroSat CZTI detection
  42. GRB 231111A NUTTelA-TAO / BSTI Early Measurements
  43. GRB 231111A: Leavitt Observatory optical observations
  44. GRB231111A: Optical follow-up observations with Mephisto
  45. GRB 231111A: GMG observation (correction)
  46. GRB 231111A: GMG observation upper limit
  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: Mondy optical observations
  50. GRB 231111A: GECAM-C detection of a long burst (correction)
  51. GRB 231110A: GECAM-B detection (correction)
  52. GRB 231111A: GECAM-C detection of a long burst
  53. GRB 231110A: GECAM detection
  54. GRB 231110A: GOTO optical upper limits
  55. GRB 231110A: SAO RAS optical observations
  56. GRB231111A: YAHPT Observations
  57. GRB231111A: GIT confirmation of the optical afterglow
  58. GRB 231111A: MASTER OT earlier detection
  59. GRB 231111A: Nanshan/HMT optical observations
  60. GRB231110A: WFST Observation and upper limits
  61. LIGO/Virgo/KAGRA S231110g: Updated Sky localization
  62. LIGO/Virgo/KAGRA S231110g: Identification of a GW compact binary merger candidate
  63. IceCube-231103A: No candidates from the Zwicky Transient Facility
  64. LIGO/Virgo/KAGRA S231108u: Updated Sky localization
  65. Fermi GRB 231108A: Global MASTER-Net observations report
  66. LIGO/Virgo/KAGRA S231108u: Identification of a GW compact binary merger candidate
  67. GRB 231106A: AstroSat CZTI detection
  68. GRB 231106A: CALET Gamma-Ray Burst Monitor detection
  69. GRB 231104A: Swift-BAT refined analysis
  70. Fermi GRB 231106A: Global MASTER-Net observations report
  71. GRB 231104A: Wendelstein Optical/Infrared Observations
  72. GRB 231104A: NuSTAR Observation of the prompt emission
  73. GRB 231104A: 3.6m DOT optical upper limit
  74. IceCube-231103A: Upper limits from a search for additional neutrino events in IceCube
  75. Fermi-LAT gamma-ray observations of IceCube-231103A
  76. GRB 231104A: NOT upper limit
  77. GRB 231104A: Fermi GBM Observation
  78. Fermi GRB 231103A: Global MASTER-Net observations report
  79. LIGO/Virgo/KAGRA S231104ac: Updated Sky localization
  80. GRB 231104A: AKO Upper Limit
  81. GRB 231104A: AstroSat CZTI detection
  82. GRB 231104A: Fermi-LAT detection
  83. LIGO/Virgo/KAGRA S231104ac: Identification of a GW compact binary merger candidate
  84. GRB 231104A: Swift/UVOT Upper Limits
  85. GRB231104A: LCOGT Optical Upper Limits
  86. Fermi-LAT gamma-ray observations of IceCube-231027A
  87. LIGO/Virgo/KAGRA S231102w: Updated Sky localization
  88. GRB 231101A: Glowbug gamma-ray detection
  89. GRB 231024A: GRANDMA observations of AT2023vuc/GOTO23baj candidate
  90. LIGO/Virgo/KAGRA S231102w: Identification of a GW compact binary merger candidate
  91. New Swift-BAT/GUANO and IceCube Notices Available via GCN Kafka
  92. GRB 231030B: GRBAlpha detection
  93. GRB 231030B: Fermi GBM Detection
  94. GRB 231030B: AstroSat CZTI detection
  95. Fermi GRB 231030B: Global MASTER-Net observations report
  96. IPN triangulation of GRB 231020A
  97. GRB 231028A: Swift-BAT refined analysis
  98. IceCube-231027A: Upper limits from a search for additional neutrino events in IceCube
  99. GRB 231024A: AKO Optical Counterpart Candidate
  100. GRB 231028A: CALET Gamma-Ray Burst Monitor detection

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