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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"

39193 results found.

  1. EP-WXT trigger 01709018832: SVOM/C-GFT observations of the star flare
  2. GRB 240807B: AstroSat CZTI detection of a short burst
  3. IceCube Alert 240808.27: Global MASTER-Net observations report
  4. EP EP240807a: Global MASTER-Net observations report
  5. EP EP240806a: Global MASTER-Net observations report
  6. GRB 240801A: GRBAlpha detection
  7. GRB 240807B: Fermi GBM Final Localization
  8. GRB 240710B: VZLUSAT-2 detection
  9. GRB 240805A: ATCA Radio Upper Limits
  10. Fermi trigger No 744761058: Global MASTER-Net observations report
  11. EP240807a/GRB 240807A: EP-FXT detection of the X-ray emission
  12. EP-WXT trigger 01709018832: KAIT optical observations of the star flare
  13. EP240802a/GRB240802A: KAIT optical upper limit
  14. GRB 240720B: VZLUSAT-2 detection
  15. GRB 240710A: VZLUSAT-2 detection
  16. GRB 240807A: Fermi GBM Final Localization
  17. EP240806a: Gemini North-GMOS spectroscopic redshift of z = 2.818
  18. GRB 240805B: GIT optical upper limit
  19. EP240806a: KAIT optical observations
  20. GRB 240805B: Swift-BAT refined analysis
  21. GRB 240805A: Swift-BAT refined analysis
  22. Fermi trigger No 744629911: Global MASTER-Net observations report
  23. EP240804a (GRB 240804B): NOT optical observations
  24. EP240806a: LCOGT optical counterpart detection
  25. Konus-Wind detection of GRB 240802A (EP240802a)
  26. Improved IPN triangulation of GRB 240802A / EP 240802a
  27. Konus-Wind detection of GRB 240805A
  28. GRB 240805B Bassano Bresciano Observatory upper limit
  29. GRB240805A: Fermi GBM Observation
  30. GRB 240805B: JinShan optical afterglow detection
  31. GRB 240804B/EP240804a: Correction to the GRB name in GCN 37071
  32. GRB 240805B: AbAO, CrAO, and Terskol optical upper limits
  33. Konus-Wind detection of GRB 240804B (a counterpart of EP240804a)
  34. Fermi Gamma-ray Burst Monitor trigger 240806402/744629911 is not a GRB
  35. GRB 240626B: VZLUSAT-2 detection
  36. GRB 240624B: VZLUSAT-2 detection
  37. GRB 240619C: VZLUSAT-2 detection
  38. EP 240806A: LCO optical observations
  39. GRB 240805B: Optical detection with 1.6m Mephisto
  40. GRB 240805B: NUTTelA-TAO / BSTI Optical Limits
  41. GRB 240805B: Swift-XRT refined Analysis
  42. Fermi trigger No 744544656: Global MASTER-Net observations report
  43. GRB 240805B: Swift/UVOT Upper Limits
  44. GRB 240805A: Swift/UVOT Upper Limits
  45. GRB 240805B: BTA optical afterglow candidate
  46. GRB 240805A: SVOM/GRM observation
  47. GRB 240805B: Enhanced Swift-XRT position
  48. GRB 240805B: LCOGT Optical Upper Limits
  49. Swift GRB 240805B: Global MASTER-Net observations report
  50. GRB 240805B: JinShan optical upper limits
  51. Fermi GRB 240805A: Global MASTER-Net observations report
  52. Swift GRB 240805A: Global MASTER-Net observations report
  53. Fermi Gamma-ray Burst Monitor trigger 744558410/240805574 is not a GRB
  54. GRB 240805A: Swift-XRT refined Analysis
  55. EP240804a: GSP detects optical candidate counterpart
  56. GRB 240805B: Swift detection of a burst
  57. GRB 240805A: Fermi-LAT detection
  58. GRB 240805A: INTEGRAL spectral analysis
  59. EP240801a: Continued optical observations at ZTSh (CraO)
  60. EP240804a: LCOGT optical counterpart detection
  61. GRB 240805A: A long GRB detected by INTEGRAL
  62. EP240804a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  63. GRB 240805A: Swift detection of a burst
  64. GRB 240805A: Fermi GBM Final Real-time Localization
  65. Fermi GRB 240804A: Global MASTER-Net observations report
  66. EP240802a: Montarrenti Observatory optical upper limit
  67. GRB 240804A: Fermi GBM Final Real-time Localization
  68. Fermi trigger No 744459130: Global MASTER-Net observations report
  69. IPN triangulation of GRB 240802A / EP 240802a
  70. Fermi Gamma-ray Burst Monitor trigger 744459130/240804425 is not a GRB
  71. EP240802A: Bassano Bresciano Observatory upper limit
  72. GRB 240802A: SVOM/GRM observation
  73. EP240802a: Time coincidence with GRB 240802A and optical upper limits with Kinder observations
  74. Fermi trigger No 744278264: Global MASTER-Net observations report
  75. GRB 240802A: AstroSat CZTI detection of a long burst
  76. EP240801a: further SAO RAS optical observations
  77. EP240801a: optical observations at CrAO and AbAO
  78. EP240801a: Leavitt Observatory optical observations
  79. EP240801a: GTC spectroscopy and absorption redshift
  80. EP240801a: SAO RAS optical observations
  81. GRB 240801B: AstroSat CZTI Updated classification - likely a solar flare
  82. EP240801a: JinShan optical observations
  83. GRB 240727C: SVOM/GRM observation
  84. EP240801a: follow-up observation with LCOGT
  85. Fermi GBM trigger 744179961 / 240801194 can not be confirmed as a GRB
  86. GRB 240730A: Swift-BAT refined analysis
  87. EP240801a: GSP follow-up observations of the candidate counterpart
  88. Fermi trigger No 744204856: Global MASTER-Net observations report
  89. EP240801a: KAIT optical counterpart observations
  90. EP240801a: TRT optical counterpart detection
  91. EP240801a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  92. GRB 240801B: AstroSat CZTI detection of a bright long burst
  93. Fermi GRB 240801A: Global MASTER-Net observations report
  94. GRB 240801A: Fermi GBM Final Real-time Localization
  95. GRB 240730C: AstroSat CZTI detection of a long burst
  96. GRB 240731A: Fermi GBM Final Localization
  97. Fermi trigger No 744128417: Global MASTER-Net observations report
  98. Fermi trigger No 744083370: Global MASTER-Net observations report
  99. GRB 240731A: AstroSat CZTI detection
  100. GRB 240730A: Osservatorio Astronomico Nastro Verde upper limit

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