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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"

32766 results found.

  1. LIGO/Virgo/KAGRA S240527fv: Identification of a GW compact binary merger candidate
  2. GRB 240527B: Fermi-LAT detection
  3. LIGO/Virgo/KAGRA S240527en: Identification of a GW compact binary merger candidate
  4. Fermi GRB 240527B: Global MASTER-Net observations report
  5. GRB 240523A: Swift-BAT refined analysis
  6. LIGO/Virgo/KAGRA S240525p: Updated Sky localization
  7. LIGO/Virgo/KAGRA S240525p: Identification of a GW compact binary merger candidate
  8. GRB 240521B: Fermi GBM Observation
  9. Fermi GBM Sub-Threshold Detection of GRB 240516B
  10. GRB 240513A: Swift-XRT afterglow detection
  11. LIGO/Virgo/KAGRA S240520cv: Updated Sky localization and EM Bright Classification
  12. EP240518a: GSP optical upper limit
  13. LIGO/Virgo/KAGRA S240520cv: Identification of a GW compact binary merger candidate
  14. GRB 240514B: VZLUSAT-2 detection
  15. GRB 240504A: VZLUSAT-2 detection
  16. GRB 240502A: VZLUSAT-2 detection
  17. GRB 240519A: GRBAlpha detection
  18. GRB 240516A: Swift/UVOT Upper Limits
  19. GRB 240519A: AstroSat CZTI detection
  20. EP240518a: possibly identified with a flare star by EP-FXT
  21. LIGO/Virgo/KAGRA S240514c: Updated Sky localization
  22. GRB 240516A: Swift-BAT refined analysis
  23. Fermi GRB 240517A: Global MASTER-Net observations report
  24. GRB 240516A ATCA radio observations
  25. IPN triangulation of GRB 240514B (short)
  26. GRB 240513A: Swift ToO observations
  27. Konus-Wind detection of GRB 240513A
  28. GRB 240516A: AstroSat CZTI detection
  29. GRB 240516A: Swift-XRT refined Analysis
  30. GRB 240514E: A possible candidate BD-21 1074
  31. GRB 240516A: Fermi GBM Observation
  32. GRB 240511A: Observations from GTC/OSIRIS+
  33. GRB 240502C: Zeiss-1000 at Koshka observations of GOTO24bao optical counterpart candidate
  34. GRB 240516A: GOTO optical upper limit
  35. GRB 240514B: AT2024ixa/GOTO24bph is not consistent with the Fermi localisation
  36. GRB 240511A: radio detection of afterglow candidate
  37. GRB 240514B: GOTO candidate optical counterpart
  38. Fermi Gamma-ray Burst Monitor list of triggers that are not a GRB
  39. GRB 240514B: GRBAlpha detection
  40. LIGO/Virgo/KAGRA S240514x: Updated Sky localization
  41. LIGO/Virgo/KAGRA S240515m: Identification of a GW compact binary merger candidate
  42. GRB 240514B: Fermi GBM Detection
  43. GRB 240513A: Fermi GBM observation
  44. LIGO/Virgo/KAGRA S240513ei: Updated Sky localization
  45. LIGO/Virgo/KAGRA S240514x: Identification of a GW compact binary merger candidate
  46. LIGO/Virgo/KAGRA S240514c: Identification of a GW compact binary merger candidate
  47. Fermi GRB 240514B: Global MASTER-Net observations report
  48. GRB 240513A: Tiled Swift observations
  49. GRB 240513A: Fermi-LAT detection
  50. LIGO/Virgo/KAGRA S240513ei: Identification of a GW compact binary merger candidate
  51. GRB 240511A: Fermi GBM Observation
  52. GRB 240511A: Swift-BAT refined analysis
  53. Fermi GRB 240513B: Global MASTER-Net observations report
  54. GRB 240511A: J-band observations with WINTER
  55. GRB 240511A : MITSuME Akeno optical upper limits
  56. LIGO/Virgo/KAGRA S240512r: Updated Sky localization and EM Bright Classification
  57. GRB 240511A: optical afterglow detection from the NOT
  58. LIGO/Virgo/KAGRA S240512r: Identification of a GW compact binary merger candidate
  59. Fermi GRB 240511A: Global MASTER-Net observations report
  60. Swift GRB 240511A: Global MASTER-Net observations report
  61. LIGO/Virgo/KAGRA S240511i: Updated Sky localization
  62. LIGO/Virgo/KAGRA S240511i: Identification of a GW compact binary merger candidate
  63. LIGO/Virgo/KAGRA S240422ed: GMOS-S photometry of J-GEM24a
  64. LIGO/Virgo/KAGRA S240422ed: Candidates from the latest GW-MMADS DECam Observations
  65. EP240506a: Xinglong optical upper limit
  66. EP240506a: CrAO ZTSH optical upper limit
  67. GRB 240504A: Fermi GBM Observation
  68. EP240506a: Archival radio searching
  69. EP240506a: TRT optical upper limit
  70. LIGO/Virgo/KAGRA S240507p: Updated Sky localization and EM Bright Classification
  71. EP240506a: Optical upper limit with Kinder observations
  72. IPN triangulation of GRB 240504A
  73. GRB 240502A: 1.3m DFOT Optical upper limit
  74. LIGO/Virgo/KAGRA S240507p: Identification of a GW compact binary merger candidate
  75. LIGO/Virgo/KAGRA S240422ed: Additional WINTER near-infrared J-band observations
  76. LIGO/Virgo/KAGRA S240422ed: Swope Follow-up of AT2024hfr and AT2024hfs
  77. LIGO/Virgo/KAGRA S240505av: Updated Sky localization and EM Bright Classification
  78. LIGO/Virgo/KAGRA S240505av: Identification of a GW compact binary merger candidate
  79. IceCube-240424A: GRANDMA Optical Upper Limit of Fermi J2151.3+0220
  80. GRB 240502C: Zeiss-1000 at Koshka observatory observations of GOTO optical counterpart candidates
  81. IPN triangulation of GRB 240501B and GRB 240501A - possible episodes of ultra long GRB
  82. Fermi GRB 240504A: Global MASTER-Net observations report
  83. LXT 240402A / GRB 240402B: VLT X-shooter redshift of host
  84. GRB 240502A: GOTO optical upper limit
  85. GRB 240502A: Fermi GBM Observation
  86. GRB 240415A 1.3m DFOT Optical upper limit
  87. GRB 240502C: GOTO possible optical counterpart candidates
  88. LIGO/Virgo/KAGRA S240501an: Updated Sky localization and EM Bright Classification
  89. LIGO/Virgo/KAGRA S240430ca: Updated Sky localization and EM Bright Classification
  90. Fermi GRB 240502B: Global MASTER-Net observations report
  91. Fermi GRB 240502A: Global MASTER-Net observations report
  92. GRB 240501B: GRBAlpha detection
  93. GRB 240430A: GRBAlpha detection
  94. LIGO/Virgo/KAGRA S240422ed: GECKO/KMTNet Transient Candidates
  95. LIGO/Virgo/KAGRA S240422ed: Host redshifts of AT2024hfq, AT2024hfu, and AT2024hmo from DBSP
  96. Fermi GRB 240501A: Global MASTER-Net observations report
  97. GRB 240426A: VZLUSAT-2 detection
  98. GRB 240425A: VZLUSAT-2 detection
  99. MeerKAT Discovery of a Probable Radio Counterpart to EP240414a
  100. GRB 240408B: VZLUSAT-2 detection

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