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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"

28262 results found.

  1. LIGO/Virgo S240615dg: Swift XRT observations, 28 futher X-ray sources
  2. EP240703b: GSP optical upper limit
  3. EP240703b: TRT optical upper limits
  4. EP240703a: TRT further optical observation
  5. EP240702a: TRT optical upper limits
  6. IPN triangulation of GRB 240628B (short)
  7. LIGO/Virgo/KAGRA S240705at: Updated Sky localization
  8. LIGO/Virgo/KAGRA S240705at: Identification of a GW compact binary merger candidate
  9. EP240703a: BTA observations
  10. EP240703c: Kinder optical follow-up and Swift XRT observations
  11. EP240703a: Liverpool Telescope optical follow-up observations
  12. EP240703a: Kinder optical follow-up observations
  13. EP240703c: EP-WXT detection of an X-ray transient
  14. LIGO/Virgo/KAGRA S240703ad: Updated Sky localization
  15. LIGO/Virgo/KAGRA S240703ad: Identification of a GW compact binary merger candidate
  16. EP240703a/GRB 240703A: TRT and JinShan decaying optical afterglow candidate
  17. GRB 240619A: Host galaxy redshift from VLT/X-shooter
  18. LIGO/Virgo/KAGRA S240422ed: Updated significance estimate
  19. The first three GRBs detected by SVOM: X-ray Upper Limits from EP-WXT
  20. EP240703b: EP-WXT detection of a fast X-ray transient
  21. EP240703a: EP-WXT detection of a fast X-ray transient
  22. EP240702a: GSP optical upper limit
  23. GRB 240702A: BALROG localization (Fermi Trigger / GRB 240702885)
  24. EP240702a: EP-WXT detection of a fast X-ray transient
  25. LIGO/Virgo/KAGRA S240627by: Upper limits from Swift/BAT-GUANO
  26. LIGO/Virgo/KAGRA S240630t: Updated Sky localization
  27. LIGO/Virgo/KAGRA S240629by: Updated Sky localization
  28. LIGO/Virgo/KAGRA S240630t: Identification of a GW compact binary merger candidate
  29. LIGO/Virgo/KAGRA S240629by: Upper limits from Fermi-GBM Observations
  30. LIGO/Virgo/KAGRA S240629by: Coverage and upper limits from MAXI/GSC observations
  31. GRB 240629A: BALROG localization (Fermi Trigger 741372837 / GRB 240629704)
  32. LIGO/Virgo/KAGRA S240629by: Identification of a GW compact binary merger candidate
  33. IPN triangulation of GRB 240619C
  34. IceCube-Cascade 240626A: Upper limits from a search for additional neutrino events in IceCube
  35. GRB 240628A: BALROG localization (Fermi Trigger 741288821 / GRB 240628732)
  36. GRB 240627A: NuSTAR Detection of the long GRB
  37. GRB 240615A: SAI CMO J- band observations
  38. GRB 240627A: AstroSat CZTI detection
  39. EP240626a: Montarrenti Observatory optical upper limit
  40. LIGO/Virgo/KAGRA S240627by: Identification of a GW compact binary merger candidate
  41. GRB 240624A: Swift-BAT refined analysis
  42. EP240626a: EP-WXT detection of a fast X-ray transient
  43. EP240625a: NOT optical counterpart candidate
  44. EP240625a: EP-FXT detection of the X-ray emission
  45. EP240625a: EP-WXT detection of a fast X-ray transient
  46. GRB240624A: Fermi GBM Observation
  47. LIGO/Virgo/KAGRA S240622h: Upper limits from Swift/BAT-GUANO
  48. LIGO/Virgo/KAGRA S240621dy: Upper limits from Swift/BAT-GUANO
  49. LIGO/Virgo/KAGRA S240618ah: Upper limits from Swift/BAT-GUANO
  50. GRB240615A: Gemini-North observations of the BAT and XRT positions
  51. GRB240615A: Gemini-North observations of the BAT and XRT positions
  52. GRB 240619A: detection of a radio counterpart with AMI-LA
  53. GRB 240624A: Swift detection of a burst
  54. GRB 240619A: J-band detection with WINTER
  55. LIGO/Virgo/KAGRA S240622h: Updated Sky localization and Source Classification
  56. EP240618a: NOT optical counterpart candidate
  57. LIGO/Virgo/KAGRA S240621em: Updated Sky localization and Source Classification
  58. GRB 240529A: JinShan optical observations
  59. LIGO/Virgo/KAGRA S240621dy: Updated Sky localization and Source Classification
  60. LIGO/Virgo/KAGRA S240621eb: Updated Sky localization and Source Classification
  61. EP240618a: GSP optical upper limit
  62. LIGO/Virgo/KAGRA S240622h: Identification of a GW compact binary merger candidate
  63. LIGO/Virgo/KAGRA S240621em: Identification of a GW compact binary merger candidate
  64. LIGO/Virgo/KAGRA S240621eb: Identification of a GW compact binary merger candidate
  65. LIGO/Virgo/KAGRA S240621dy: Identification of a GW compact binary merger candidate
  66. GRB 240619C: NuSTAR automated detection of the GRB
  67. GRB 240619A: Fermi GBM Observation
  68. Fermi GBM Sub-Threshold Detection of GRB 240619C
  69. GRB 240615A: NOT optical observations
  70. GRB 240619C: AstroSat CZTI detection
  71. EP240618a: TRT optical upper limit
  72. EP240617a: STEP/T80S optical limits
  73. GRB 240615A: possible transient detection from Wendelstein observations
  74. LIGO/Virgo/KAGRA S240615dg: Updated Sky localization
  75. LIGO/Virgo/KAGRA S240618ah: Updated Sky localization
  76. EP240618a: OHP/T193 MISTRAL i' and Y band upper limits
  77. LIGO/Virgo S240615dg: Swift XRT observations, 39 X-ray sources
  78. GRB240615A: 1.3m DFOT optical upper limit
  79. GRB 240619A: BALROG localization (Fermi Trigger 740461416 / GRB 240619155)
  80. EP240617a: EP-WXT detection of a fast X-ray transient
  81. EP240618a: EP-WXT detection of a fast X-ray transient and EP-FXT quick follow-up
  82. LIGO/Virgo/KAGRA S240618ah: Identification of a GW compact binary merger candidate
  83. LIGO/Virgo/KAGRA S240615ea: Upper limits from Swift/BAT-GUANO
  84. LIGO/Virgo/KAGRA S240615dg: Upper limits from Swift/BAT-GUANO
  85. GRB 240615A: J-band upper limits from WINTER
  86. LIGO/Virgo/KAGRA S240615ea: Updated Sky localization
  87. GRB 240615A: Swift-XRT observations
  88. X-ray transient EP240414a: Chandra late time observation
  89. GRB 240615A: Swift/BAT-GUANO arcminute localization of a short burst
  90. LIGO/Virgo/KAGRA S240615ea: Identification of a GW compact binary merger candidate
  91. LIGO/Virgo/KAGRA S240615dg: Identification of a GW compact binary merger candidate
  92. GRB 240603A: VZLUSAT-2 detection
  93. EXO 0748-676: Swift-BAT refined analysis
  94. GRB240529A: 3.6m TNG NIR detection 8d after the burst
  95. GRB 240529A: LBT optical detection and late temporal decay
  96. GRB 240529A : MITSuME Akeno optical afterglow detection
  97. Trigger 1236151: Swift detection of EXO 0748-676
  98. IPN triangulation of GRB 240607A
  99. Fermi trigger No 739632045: Global MASTER-Net observations report
  100. GRB 240607A: Fermi GBM Observation

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