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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"

32494 results found.

  1. GRB 240529A: 1.3m DFOT Optical observations
  2. LIGO/Virgo/KAGRA S240527en: Updated Sky localization
  3. LIGO/Virgo/KAGRA S240601aj: Identification of a GW compact binary merger candidate
  4. GRB 240529A : Mondy optical observations
  5. Konus-Wind detection of GRB 240529A
  6. IPN triangulation of the initial episode of GRB 240529A
  7. GRB 240529A: SAO RAS optical observations
  8. LIGO/Virgo/KAGRA S240531bp: Updated Sky localization
  9. LIGO/Virgo/KAGRA S240531bp: Identification of a GW compact binary merger candidate
  10. GRB 240529A: MAAO 0.7m telescope optical afterglow detection
  11. GRB 240529A: Insight-HXMT/HE detection
  12. GRB 240529A: optical photometry from Konkoly
  13. GRB 240529A: GROWTH-India optical follow-up
  14. GRB 240529A: T193/MISTRAL observations
  15. GRB 240529A: Redshift from GTC/OSIRIS+
  16. GRB 240529A: AKO Optical Afterglow Detection
  17. LIGO/Virgo/KAGRA S240530a: Identification of a GW compact binary merger candidate
  18. GRB 240529A: J-band detections with WINTER
  19. GRB 240529A: Skynet Optical Observations
  20. GRB 240529A: Swift-BAT refined analysis
  21. LIGO/Virgo S240527fv: GRANDMA/FRAM-Auger Optical Observations
  22. GRB 240529A: Swift/UVOT Detection
  23. GRB 240529A: NOT optical observations
  24. GRB 240529A: AstroSat CZTI detection
  25. GRB 240529A: GOTO optical afterglow detection
  26. LIGO/Virgo/KAGRA S240527fv: Updated Sky localization
  27. GRB 240527B: Fermi GBM Observation
  28. Fermi GRB 240527A: Global MASTER-Net observations report
  29. LIGO/Virgo/KAGRA S240527fv: Identification of a GW compact binary merger candidate
  30. GRB 240527B: Fermi-LAT detection
  31. LIGO/Virgo/KAGRA S240527en: Identification of a GW compact binary merger candidate
  32. Fermi GRB 240527B: Global MASTER-Net observations report
  33. GRB 240523A: Swift-BAT refined analysis
  34. LIGO/Virgo/KAGRA S240525p: Updated Sky localization
  35. LIGO/Virgo/KAGRA S240525p: Identification of a GW compact binary merger candidate
  36. GRB 240521B: Fermi GBM Observation
  37. Fermi GBM Sub-Threshold Detection of GRB 240516B
  38. GRB 240513A: Swift-XRT afterglow detection
  39. LIGO/Virgo/KAGRA S240520cv: Updated Sky localization and EM Bright Classification
  40. EP240518a: GSP optical upper limit
  41. LIGO/Virgo/KAGRA S240520cv: Identification of a GW compact binary merger candidate
  42. GRB 240514B: VZLUSAT-2 detection
  43. GRB 240504A: VZLUSAT-2 detection
  44. GRB 240502A: VZLUSAT-2 detection
  45. GRB 240519A: GRBAlpha detection
  46. GRB 240516A: Swift/UVOT Upper Limits
  47. GRB 240519A: AstroSat CZTI detection
  48. EP240518a: possibly identified with a flare star by EP-FXT
  49. LIGO/Virgo/KAGRA S240514c: Updated Sky localization
  50. GRB 240516A: Swift-BAT refined analysis
  51. Fermi GRB 240517A: Global MASTER-Net observations report
  52. GRB 240516A ATCA radio observations
  53. IPN triangulation of GRB 240514B (short)
  54. GRB 240513A: Swift ToO observations
  55. Konus-Wind detection of GRB 240513A
  56. GRB 240516A: AstroSat CZTI detection
  57. GRB 240516A: Swift-XRT refined Analysis
  58. GRB 240514E: A possible candidate BD-21 1074
  59. GRB 240516A: Fermi GBM Observation
  60. GRB 240511A: Observations from GTC/OSIRIS+
  61. GRB 240502C: Zeiss-1000 at Koshka observations of GOTO24bao optical counterpart candidate
  62. GRB 240516A: GOTO optical upper limit
  63. GRB 240514B: AT2024ixa/GOTO24bph is not consistent with the Fermi localisation
  64. GRB 240511A: radio detection of afterglow candidate
  65. GRB 240514B: GOTO candidate optical counterpart
  66. Fermi Gamma-ray Burst Monitor list of triggers that are not a GRB
  67. GRB 240514B: GRBAlpha detection
  68. LIGO/Virgo/KAGRA S240514x: Updated Sky localization
  69. LIGO/Virgo/KAGRA S240515m: Identification of a GW compact binary merger candidate
  70. GRB 240514B: Fermi GBM Detection
  71. GRB 240513A: Fermi GBM observation
  72. LIGO/Virgo/KAGRA S240513ei: Updated Sky localization
  73. LIGO/Virgo/KAGRA S240514x: Identification of a GW compact binary merger candidate
  74. LIGO/Virgo/KAGRA S240514c: Identification of a GW compact binary merger candidate
  75. Fermi GRB 240514B: Global MASTER-Net observations report
  76. GRB 240513A: Tiled Swift observations
  77. GRB 240513A: Fermi-LAT detection
  78. LIGO/Virgo/KAGRA S240513ei: Identification of a GW compact binary merger candidate
  79. GRB 240511A: Fermi GBM Observation
  80. GRB 240511A: Swift-BAT refined analysis
  81. Fermi GRB 240513B: Global MASTER-Net observations report
  82. GRB 240511A: J-band observations with WINTER
  83. GRB 240511A : MITSuME Akeno optical upper limits
  84. LIGO/Virgo/KAGRA S240512r: Updated Sky localization and EM Bright Classification
  85. GRB 240511A: optical afterglow detection from the NOT
  86. LIGO/Virgo/KAGRA S240512r: Identification of a GW compact binary merger candidate
  87. Fermi GRB 240511A: Global MASTER-Net observations report
  88. Swift GRB 240511A: Global MASTER-Net observations report
  89. LIGO/Virgo/KAGRA S240511i: Updated Sky localization
  90. LIGO/Virgo/KAGRA S240511i: Identification of a GW compact binary merger candidate
  91. LIGO/Virgo/KAGRA S240422ed: GMOS-S photometry of J-GEM24a
  92. LIGO/Virgo/KAGRA S240422ed: Candidates from the latest GW-MMADS DECam Observations
  93. EP240506a: Xinglong optical upper limit
  94. EP240506a: CrAO ZTSH optical upper limit
  95. GRB 240504A: Fermi GBM Observation
  96. EP240506a: Archival radio searching
  97. EP240506a: TRT optical upper limit
  98. LIGO/Virgo/KAGRA S240507p: Updated Sky localization and EM Bright Classification
  99. EP240506a: Optical upper limit with Kinder observations
  100. IPN triangulation of GRB 240504A

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