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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"

6094 results found.

  1. GRB 240825A: Swift-BAT refined analysis
  2. GRB 240828A: SAO RAS optical observations
  3. GRB 240828A: Fermi GBM Observation
  4. GRB 240828A: Swift-XRT afterglow detection
  5. GRB 240825A: further SAO RAS optical observations
  6. GRB 240825A: iTelescope optical observations
  7. GRB 240828B: Swift-XRT afterglow detection
  8. GRB 240828A: Fermi-LAT detection
  9. GRB 240821A: the second and third EP-FXT follow-up observations and afterglow candidates
  10. GRB 240819A: Swift afterglow confirmation
  11. Konus-Wind detection of GRB 240825A (bright/long)
  12. GRB 240825A: Fermi GBM Observation
  13. GRB 240825A: Swift-XRT refined Analysis
  14. GRB 240825A: Fermi-LAT detection
  15. GRB 240824B: Fermi GBM Observation
  16. GRB 240824B: Swift-XRT afterglow detection
  17. GRB 240824A: Swift-XRT observations
  18. GRB 240821A: Swift/UVOT observations of the XRT sources.
  19. GRB 240821A: Swift-XRT observations
  20. GECAM-B observation of a short burst from SGR 1E 1841-045 / Kes 73
  21. GRB 240821A: Fermi GBM Observation
  22. GRB 240821A: EP-FXT follow-up observation and afterglow candidates
  23. GRB 240819A: Swift-XRT observations
  24. EP240820a: EP detection of a fast X-ray transient
  25. GRB 240819A: X-ray follow-up observation with EP-FXT
  26. EP240816b: TRT optical upper limit
  27. EP240802a: Kinder optical, SWIFT-UVOT, and SWIFT-XRT upper limits 6 days after the WXT detection
  28. Konus-Wind detection of GRB 240811A
  29. GRB 240811A: Swift-XRT refined Analysis
  30. Konus-Wind detection of GRB 240809A
  31. Konus-Wind detection of GRB 240807A (a counterpart of EP240807a)
  32. Fermi-LAT gamma-ray observations of IceCube-240808A
  33. GRB 240809A: GIT afterglow observations
  34. GRB 240809A: Tentative redshift from NOT
  35. GRB 240809A: Swift-XRT refined Analysis
  36. GRB 240809A: JinShan optical observations
  37. The EP-WXT trigger 01709018832 on August 7th is likely a flaring star
  38. EP240806a: Gemini North-GMOS spectroscopic redshift of z = 2.818
  39. EP240804a (GRB 240804B): NOT optical observations
  40. EP240806a: LCOGT optical counterpart detection
  41. GRB240805A: Fermi GBM Observation
  42. Konus-Wind detection of GRB 240804B (a counterpart of EP240804a)
  43. GRB 240805B: Swift-XRT refined Analysis
  44. GRB 240805A: Swift-XRT refined Analysis
  45. GRB 240805A: Fermi-LAT detection
  46. EP240804a: LCOGT optical counterpart detection
  47. EP240802a: Time coincidence with GRB 240802A and optical upper limits with Kinder observations
  48. EP240801a: further SAO RAS optical observations
  49. EP240801a: SAO RAS optical observations
  50. EP240801a: follow-up observation with LCOGT
  51. EP240801a: Kinder follow-up observations of the candidate counterpart
  52. EP240801a: TRT optical counterpart detection
  53. GRB 240730A: Swift-XRT refined Analysis
  54. GRB 240715A: Swift-XRT afterglow detection
  55. GRB 240730A: Swift detection of a burst
  56. GRB 240727B: Swift-XRT observations
  57. GRB 240727A: Swift-XRT refined Analysis
  58. GRB 240727B: Fermi GBM Observation
  59. GRB 240727A: TRT optical afterglow detection
  60. Fermi-LAT gamma-ray observations of IceCube-240725A
  61. Fermi-LAT gamma-ray observations of IceCube-240721A
  62. GRB 240720A: Fermi GBM observation
  63. GRB 240718A: Fermi GBM Observation
  64. GRB 240718A: Fermi-LAT Detection
  65. IceCube-Cascade 240714A: X-ray follow-up observation with EP-FXT
  66. Fermi-LAT gamma-ray observations of IceCube-cascade-240714A
  67. GRB 240715A: Swift/UVOT observations of the XRT sources.
  68. GRB 240715A: Swift-XRT observations
  69. GRB240713A: Swift/UVOT Upper LImits
  70. GRB 240715A: GECAM-C detection of a short burst
  71. GRB 240713A: Swift-XRT observations
  72. GRB 240715A: TRT optical upper limit on one Swift/XRT candidate
  73. GRB 240712A: Swift-XRT refined Analysis
  74. GRB 240715A: Fermi GBM Observation
  75. The EP-WXT source triggered on July 14th is likely a flaring star
  76. GRB 240713A: NOT optical upper limits on three EP/FXT candidates
  77. GRB240713A: X-ray follow-up observation with EP-FXT
  78. GRB 240713B: AstroSat CZTI detection of a long burst
  79. GRB240713A: Optical upper limit with Kinder observations
  80. EP240708a: NOT optical observations
  81. EP240708a: Optical upper limits with Kinder observations
  82. EP240703c: Kinder optical follow-up and Swift XRT observations
  83. EP240703a: Kinder optical follow-up observations
  84. EP240703c: EP-WXT detection of an X-ray transient
  85. EP240703a/GRB 240703A: TRT and JinShan decaying optical afterglow candidate
  86. EP240703a: EP-WXT detection of a fast X-ray transient
  87. Konus-Wind detection of GRB 240619A
  88. GRB 240625A: Fermi GBM Observation
  89. EP240625a: EP-WXT detection of a fast X-ray transient
  90. GRB240624A: Fermi GBM Observation
  91. X-ray transient EP240618a: Fermi/GBM non-detection
  92. EP240618a: Swift/XRT upper limit
  93. EP240617a: tentative Swift/XRT detection of the afterglow
  94. GRB 240619A: Swift-XRT probable afterglow detection
  95. GRB 240619A: Fermi GBM Observation
  96. LIGO/Virgo S240615dg: Swift XRT observations, 39 X-ray sources
  97. Fermi trigger No 740430582: Global MASTER-Net observations report
  98. GRB240615A: 1.3m DFOT optical upper limit
  99. EP240617a: EP-WXT detection of a fast X-ray transient
  100. GRB 240615A: Fermi GBM Observation

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