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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"

11752 results found.

  1. LAT GRB240828.62: Global MASTER-Net observations report
  2. GRB 240828A: AstroSat CZTI detection of a long burst
  3. Fermi GRB 240828A: Bassano Bresciano Observatory upper limit
  4. GRB 240819A as a likely X-Ray Flash
  5. GRB 240821A: PRIME near-infrared observations
  6. Fermi trigger No 746438824: Global MASTER-Net observations report
  7. GRB 240825A: TNG optical photometry and spectroscopy
  8. Konus-Wind detection of GRB 240825A (bright/long)
  9. GRB 240825A: AstroSat CZTI detection of the long bright burst
  10. GRB 240825A: Swift/UVOT Detection
  11. GRB 240825A: Swift-XRT refined Analysis
  12. GRB 240825A: Fermi-LAT detection
  13. GRB 240825A: LCO optical observations
  14. SGR 1E 1841-045 / Kes 73 (Trigger 1249878): Osservatorio Atronomico Nastro Verde optical upper limit
  15. Fermi GRB 240825A: Global MASTER-Net observations report
  16. SGR 1E 1841-045 / Kes 73 (Trigger 1249653) - Osservatorio Astronomico Nastro Verde upper limit
  17. GRB 240824B: MAXI/GSC detection
  18. SGR 1E 1841-045 / Kes 73: Leavitt Observatory optical upper limit
  19. SGR 1E 1841-045 / Kes 73: Montarrenti Observatory optical upper limits
  20. GRB 240821A: Colibri Optical Upper Limit
  21. GRB 240822A: AstroSat CZTI detection of a short burst
  22. Fermi trigger No 745866488: Global MASTER-Net observations report
  23. Trigger 1249878: Swift detection of another burst from SGR 1E 1841-045 / Kes 73
  24. GRB 240819A: Swift-XRT observations
  25. GRB 240819A: JinShan optical upper limits on one Swift/XRT source
  26. EP240820a: EP detection of a fast X-ray transient
  27. Fermi trigger No 745873283: Global MASTER-Net observations report
  28. Fermi trigger No 745871958: Global MASTER-Net observations report
  29. Fermi Gamma-ray Burst Monitor trigger 745811685 / 240820080 is not a GRB
  30. GRB 240820A: Fermi GBM Final Real-time Localization
  31. Integral GRB240816.79: Global MASTER-Net observations report
  32. GRB GRB 240809A: Osservatorio Astronomico "Nastro Verde" optical observations: detection of an optical counterpart
  33. GRB 240805B: Osservatorio Astronomico Nastro Verde upper limit
  34. EP240816a: EP detection of a fast X-ray transient and follow-up observation
  35. EP240816b: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  36. Konus-Wind detection of GRB 240811A
  37. Konus-Wind detection of GRB 240810A
  38. IPN triangulation of GRB 240810A (short)
  39. GRB 240812B: AstroSat CZTI detection of a long burst
  40. GRB 240811A: Bassano Bresciano Observatory upper limit
  41. GRB 240811A: Swift-XRT refined Analysis
  42. EP240801a: Assy-Turgen optical observations
  43. GRB 240811A: LCOGT Optical Upper Limit
  44. Konus-Wind detection of GRB 240809A
  45. Fermi trigger No 745057312: Global MASTER-Net observations report
  46. Swift GRB 240811A: Global MASTER-Net observations report
  47. GRB 240811A: Swift detection of a burst
  48. GRB 240809A: Bassano Bresciano Observatory optical observations
  49. Konus-Wind detection of GRB 240807A (a counterpart of EP240807a)
  50. Fermi-LAT gamma-ray observations of IceCube-240808A
  51. GRB 240808A: AstroSat CZTI detection
  52. GRB 240809B: MAXI/GSC detection
  53. GRB 240809A: Swift detection of a burst with a bright optical counterpart
  54. EP240807a: STEP/T80S optical limits
  55. GRB 240807B: AstroSat CZTI detection of a short burst
  56. EP EP240807a: Global MASTER-Net observations report
  57. EP EP240806a: Global MASTER-Net observations report
  58. EP240807a/GRB 240807A: EP-FXT detection of the X-ray emission
  59. GRB 240720B: VZLUSAT-2 detection
  60. Fermi trigger No 744629911: Global MASTER-Net observations report
  61. Konus-Wind detection of GRB 240802A (EP240802a)
  62. Konus-Wind detection of GRB 240805A
  63. GRB 240805B Bassano Bresciano Observatory upper limit
  64. GRB 240805B: AbAO, CrAO, and Terskol optical upper limits
  65. Konus-Wind detection of GRB 240804B (a counterpart of EP240804a)
  66. GRB 240805B: Swift-XRT refined Analysis
  67. Fermi trigger No 744544656: Global MASTER-Net observations report
  68. GRB 240805A: Fermi-LAT detection
  69. GRB 240805A: INTEGRAL spectral analysis
  70. EP240801a: Continued optical observations at ZTSh (CraO)
  71. EP240804a: VLT/X-shooter spectroscopic redshift
  72. GRB 240805A: A long GRB detected by INTEGRAL
  73. EP240804a: NOT optical counterpart detection
  74. EP240804a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  75. GRB 240805A: Fermi GBM Final Real-time Localization
  76. EP240801a: Osservatorio Astronomico Nastro Verde upper limit
  77. GRB 240802A: AstroSat CZTI detection of a long burst
  78. EP240801a: optical observations at CrAO and AbAO
  79. EP240801a: Leavitt Observatory optical observations
  80. GRB 240801B: AstroSat CZTI detection of a bright long burst
  81. Fermi GRB 240801A: Global MASTER-Net observations report
  82. GRB 240730C: AstroSat CZTI detection of a long burst
  83. GRB 240731A: Fermi GBM Final Localization
  84. GRB 240731A: AstroSat CZTI detection
  85. GRB 240730A: Osservatorio Astronomico Nastro Verde upper limit
  86. Fermi GRB 240727A: Global MASTER-Net observations report
  87. GRB 240727A: Swift/UVOT detection
  88. GRB 240727A: Correction to time in GCN36960
  89. GRB 240727A: Osservatorio Astronomico Nastro Verde upper limit
  90. GRB 240727A Bassano Bresciano Observatory upper limit
  91. GRB 240727C: AstroSat CZTI detection of a long burst
  92. GRB 240727A: Swift-XRT refined Analysis
  93. GRB 240720B: GRBAlpha detection
  94. Fermi GRB 240726A: Global MASTER-Net observations report
  95. GRB 240727B: AstroSat CZTI detection
  96. GRB 240726B: AstroSat CZTI detection of a short burst
  97. GRB 240727A: Swift detection of a burst
  98. GRB 240726A: AstroSat CZTI detection of a short burst
  99. Fermi-LAT gamma-ray observations of IceCube-240725A
  100. IceCube-240721A: Upper limits from a search for additional neutrino events in IceCube

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