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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').
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"

11756 results found.

  1. GRB 240828B: SAO RAS optical upper limit
  2. Fermi trigger No 746587425: Global MASTER-Net observations report
  3. GRB 240828A: Swift-XRT afterglow detection
  4. GRB 240828A: Fermi-LAT detection
  5. LAT GRB240828.62: Global MASTER-Net observations report
  6. GRB 240828A: AstroSat CZTI detection of a long burst
  7. Fermi GRB 240828A: Bassano Bresciano Observatory upper limit
  8. GRB 240819A as a likely X-Ray Flash
  9. GRB 240821A: PRIME near-infrared observations
  10. Fermi trigger No 746438824: Global MASTER-Net observations report
  11. GRB 240825A: TNG optical photometry and spectroscopy
  12. Konus-Wind detection of GRB 240825A (bright/long)
  13. GRB 240825A: AstroSat CZTI detection of the long bright burst
  14. GRB 240825A: Swift/UVOT Detection
  15. GRB 240825A: Swift-XRT refined Analysis
  16. GRB 240825A: Fermi-LAT detection
  17. GRB 240825A: LCO optical observations
  18. SGR 1E 1841-045 / Kes 73 (Trigger 1249878): Osservatorio Atronomico Nastro Verde optical upper limit
  19. Fermi GRB 240825A: Global MASTER-Net observations report
  20. SGR 1E 1841-045 / Kes 73 (Trigger 1249653) - Osservatorio Astronomico Nastro Verde upper limit
  21. GRB 240824B: MAXI/GSC detection
  22. SGR 1E 1841-045 / Kes 73: Leavitt Observatory optical upper limit
  23. SGR 1E 1841-045 / Kes 73: Montarrenti Observatory optical upper limits
  24. GRB 240821A: Colibri Optical Upper Limit
  25. GRB 240822A: AstroSat CZTI detection of a short burst
  26. Fermi trigger No 745866488: Global MASTER-Net observations report
  27. Trigger 1249878: Swift detection of another burst from SGR 1E 1841-045 / Kes 73
  28. GRB 240819A: Swift-XRT observations
  29. GRB 240819A: JinShan optical upper limits on one Swift/XRT source
  30. EP240820a: EP detection of a fast X-ray transient
  31. Fermi trigger No 745873283: Global MASTER-Net observations report
  32. Fermi trigger No 745871958: Global MASTER-Net observations report
  33. Fermi Gamma-ray Burst Monitor trigger 745811685 / 240820080 is not a GRB
  34. GRB 240820A: Fermi GBM Final Real-time Localization
  35. Integral GRB240816.79: Global MASTER-Net observations report
  36. GRB GRB 240809A: Osservatorio Astronomico "Nastro Verde" optical observations: detection of an optical counterpart
  37. GRB 240805B: Osservatorio Astronomico Nastro Verde upper limit
  38. EP240816a: EP detection of a fast X-ray transient and follow-up observation
  39. EP240816b: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  40. Konus-Wind detection of GRB 240811A
  41. Konus-Wind detection of GRB 240810A
  42. IPN triangulation of GRB 240810A (short)
  43. GRB 240812B: AstroSat CZTI detection of a long burst
  44. GRB 240811A: Bassano Bresciano Observatory upper limit
  45. GRB 240811A: Swift-XRT refined Analysis
  46. EP240801a: Assy-Turgen optical observations
  47. GRB 240811A: LCOGT Optical Upper Limit
  48. Konus-Wind detection of GRB 240809A
  49. Fermi trigger No 745057312: Global MASTER-Net observations report
  50. Swift GRB 240811A: Global MASTER-Net observations report
  51. GRB 240811A: Swift detection of a burst
  52. GRB 240809A: Bassano Bresciano Observatory optical observations
  53. Konus-Wind detection of GRB 240807A (a counterpart of EP240807a)
  54. Fermi-LAT gamma-ray observations of IceCube-240808A
  55. GRB 240808A: AstroSat CZTI detection
  56. GRB 240809B: MAXI/GSC detection
  57. GRB 240809A: Swift detection of a burst with a bright optical counterpart
  58. EP240807a: STEP/T80S optical limits
  59. GRB 240807B: AstroSat CZTI detection of a short burst
  60. EP EP240807a: Global MASTER-Net observations report
  61. EP EP240806a: Global MASTER-Net observations report
  62. EP240807a/GRB 240807A: EP-FXT detection of the X-ray emission
  63. GRB 240720B: VZLUSAT-2 detection
  64. Fermi trigger No 744629911: Global MASTER-Net observations report
  65. Konus-Wind detection of GRB 240802A (EP240802a)
  66. Konus-Wind detection of GRB 240805A
  67. GRB 240805B Bassano Bresciano Observatory upper limit
  68. GRB 240805B: AbAO, CrAO, and Terskol optical upper limits
  69. Konus-Wind detection of GRB 240804B (a counterpart of EP240804a)
  70. GRB 240805B: Swift-XRT refined Analysis
  71. Fermi trigger No 744544656: Global MASTER-Net observations report
  72. GRB 240805A: Fermi-LAT detection
  73. GRB 240805A: INTEGRAL spectral analysis
  74. EP240801a: Continued optical observations at ZTSh (CraO)
  75. EP240804a: VLT/X-shooter spectroscopic redshift
  76. GRB 240805A: A long GRB detected by INTEGRAL
  77. EP240804a: NOT optical counterpart detection
  78. EP240804a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  79. GRB 240805A: Fermi GBM Final Real-time Localization
  80. EP240801a: Osservatorio Astronomico Nastro Verde upper limit
  81. GRB 240802A: AstroSat CZTI detection of a long burst
  82. EP240801a: optical observations at CrAO and AbAO
  83. EP240801a: Leavitt Observatory optical observations
  84. GRB 240801B: AstroSat CZTI detection of a bright long burst
  85. Fermi GRB 240801A: Global MASTER-Net observations report
  86. GRB 240730C: AstroSat CZTI detection of a long burst
  87. GRB 240731A: Fermi GBM Final Localization
  88. GRB 240731A: AstroSat CZTI detection
  89. GRB 240730A: Osservatorio Astronomico Nastro Verde upper limit
  90. Fermi GRB 240727A: Global MASTER-Net observations report
  91. GRB 240727A: Swift/UVOT detection
  92. GRB 240727A: Correction to time in GCN36960
  93. GRB 240727A: Osservatorio Astronomico Nastro Verde upper limit
  94. GRB 240727A Bassano Bresciano Observatory upper limit
  95. GRB 240727C: AstroSat CZTI detection of a long burst
  96. GRB 240727A: Swift-XRT refined Analysis
  97. GRB 240720B: GRBAlpha detection
  98. Fermi GRB 240726A: Global MASTER-Net observations report
  99. GRB 240727B: AstroSat CZTI detection
  100. GRB 240726B: AstroSat CZTI detection of a short burst

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