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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"

45790 results found.

  1. GRB 240605A: Fermi GBM Final Real-time Localization
  2. GRB 240604A: GECAM detection of a long burst
  3. GRB 240529A: SAO RAS optical observations
  4. Swift Trigger 1232755: likely consistent with noise and not astrophysical
  5. Fermi GRB 240603C: Global MASTER-Net observations report
  6. LIGO/Virgo/KAGRA S240601co: Upper limits from Swift/BAT-GUANO
  7. LIGO/Virgo/KAGRA S240530a: Upper limits from Swift/BAT-GUANO
  8. GRB 240603A: Fermi GBM Final Localization
  9. GRB 240603C: BALROG localization (Fermi Trigger 739102156 / GRB 240603423)
  10. GRB 240603C: Fermi GBM Final Real-time Localization
  11. Swift Trigger 1232465: consistent with noise
  12. GRB 240603B: Swift detection of a possible burst
  13. GRB 240529A: MASTER prompt OT detection
  14. GRB 240603A: GECAM detection of a short burst
  15. GRB 240529A: continued SAO RAS optical observations
  16. Fermi GRB 240602A: Global MASTER-Net observations report
  17. GRB 240529A: OSN optical detection
  18. The EP-WXT source triggered on June 1st is likely a flaring star
  19. GRB 240529A: further SAO RAS optical observations
  20. LIGO/Virgo/KAGRA S240601aj: Updated Sky localization
  21. GRB 240602A: Fermi GBM Final Real-time Localization
  22. LIGO/Virgo/KAGRA S240601co: Identification of a GW compact binary merger candidate
  23. Swift Trigger 1232465 is not a GRB
  24. GRB 240529A: AKO Optical Afterglow Follow-Up Observations
  25. LIGO/Virgo/KAGRA S240530a: Updated Sky localization
  26. LXT 240528A: GSP optical upper limit
  27. GRB 240529A: 1.3m DFOT Optical observations
  28. LIGO/Virgo/KAGRA S240527en: Updated Sky localization
  29. LIGO/Virgo/KAGRA S240601aj: Identification of a GW compact binary merger candidate
  30. GRB 240531A: AstroSat CZTI detection of a short burst
  31. GRB 240529A : Mondy optical observations
  32. Konus-Wind detection of GRB 240529A
  33. IPN triangulation of the initial episode of GRB 240529A
  34. GRB 240529A: SAO RAS optical observations
  35. LIGO/Virgo/KAGRA S240531bp: Updated Sky localization
  36. LIGO/Virgo/KAGRA S240531bp: Identification of a GW compact binary merger candidate
  37. GRB 240529A: MAAO 0.7m telescope optical afterglow detection
  38. GRB 240529A: Insight-HXMT/HE detection
  39. GRB 240529A: optical photometry from Konkoly
  40. GRB 240529A: GROWTH-India optical follow-up
  41. GRB 240529A: T193/MISTRAL observations
  42. GRB 240529A: Redshift from GTC/OSIRIS+
  43. GRB 240529A: AKO Optical Afterglow Detection
  44. LIGO/Virgo/KAGRA S240530a: Identification of a GW compact binary merger candidate
  45. LIGO/Virgo/KAGRA S240527fv: Upper limits from Swift/BAT-GUANO
  46. LIGO/Virgo/KAGRA S240525p: Upper limits from Swift/BAT-GUANO
  47. GRB 240529A: J-band detections with WINTER
  48. GRB 240529A: Skynet Optical Observations
  49. LXT 240528A: LEIA detection of a fast X-ray transient
  50. GRB 240529A: Swift-BAT refined analysis
  51. LIGO/Virgo S240527fv: GRANDMA/FRAM-Auger Optical Observations
  52. GRB 240529A: Swift-XRT refined Analysis
  53. GRB240529A: BOOTES-6/DPRT optical detection
  54. GRB 240529A: Swift/UVOT Detection
  55. GRB 240529A: NOT optical observations
  56. GRB 240529A: AstroSat CZTI detection
  57. GRB 240529A: GOTO optical afterglow detection
  58. GRB 240527B: Swift-XRT afterglow detection
  59. GRB 240529A: Enhanced Swift-XRT position
  60. GRB 240529A: Swift detection of a burst with an optical counterpart
  61. Swift GRB240529.12: Global MASTER-Net observations report
  62. LIGO/Virgo/KAGRA S240527fv: Updated Sky localization
  63. GRB 240527B: Fermi GBM Observation
  64. Fermi GRB 240527A: Global MASTER-Net observations report
  65. LIGO/Virgo/KAGRA S240527fv: Identification of a GW compact binary merger candidate
  66. GRB 240527B: Fermi-LAT detection
  67. LAT GRB240527.59: Global MASTER-Net observations report
  68. LIGO/Virgo/KAGRA S240527en: Identification of a GW compact binary merger candidate
  69. Fermi GRB 240527B: Global MASTER-Net observations report
  70. GRB 240527B: Fermi GBM Final Localization
  71. GRB 240527B: BALROG localization (Fermi Trigger 738511436 / GRB 240527586)
  72. GRB 240527A: Fermi GBM Final Real-time Localization
  73. GRB 240523A: Swift-BAT refined analysis
  74. Fermi trigger No 738348224: Global MASTER-Net observations report
  75. Fermi trigger No 738330463: Global MASTER-Net observations report
  76. LIGO/Virgo/KAGRA S240525p: Updated Sky localization
  77. LIGO/Virgo/KAGRA S240525p: Identification of a GW compact binary merger candidate
  78. GRB 240523A: Swift-XRT refined Analysis
  79. GRB 240523A: Enhanced Swift-XRT position
  80. GRB 240523A: Swift detection of a burst
  81. GRB 240521B: Fermi GBM Observation
  82. Fermi GBM Sub-Threshold Detection of GRB 240516B
  83. GRB 240513A: Swift-XRT afterglow detection
  84. GRB 240521B: Swift/BAT-GUANO arcminute localization of a long burst
  85. Fermi trigger No 737996942: Global MASTER-Net observations report
  86. LIGO/Virgo/KAGRA S240520cv: Updated Sky localization and EM Bright Classification
  87. EP240518a: GSP optical upper limit
  88. GRB 240521A: GECAM-B detection of a long burst
  89. GRB 240516B: AstroSat CZTI detection
  90. LIGO/Virgo/KAGRA S240515m: Upper limits from Swift/BAT-GUANO
  91. LIGO/Virgo/KAGRA S240514x: Upper limits from Swift/BAT-GUANO
  92. LIGO/Virgo/KAGRA S240513ei: Upper limits from Swift/BAT-GUANO
  93. LIGO/Virgo/KAGRA S240520cv: Identification of a GW compact binary merger candidate
  94. IceCube-Cascade 240518A: Upper limits from a search for additional neutrino events in IceCube
  95. GRB 240514B: VZLUSAT-2 detection
  96. GRB 240504A: VZLUSAT-2 detection
  97. GRB 240502A: VZLUSAT-2 detection
  98. GRB 240519A: GRBAlpha detection
  99. GRB 240516A: Swift/UVOT Upper Limits
  100. GRB 240519A: AstroSat CZTI detection

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