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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"

6792 results found.

  1. GRB 240828A: Fermi GBM Observation
  2. GRB 240828A: Swift-XRT afterglow detection
  3. GRB 240825A: further SAO RAS optical observations
  4. GRB 240825A: iTelescope optical observations
  5. GRB 240828B: Swift-XRT afterglow detection
  6. GRB 240828A: Fermi-LAT detection
  7. GRB 240821A: the second and third EP-FXT follow-up observations and afterglow candidates
  8. GRB 240819A: Swift afterglow confirmation
  9. Konus-Wind detection of GRB 240825A (bright/long)
  10. GRB 240825A: Fermi GBM Observation
  11. GRB 240825A: Swift-XRT refined Analysis
  12. GRB 240825A: Fermi-LAT detection
  13. GRB 240824B: Fermi GBM Observation
  14. GRB 240824B: Swift-XRT afterglow detection
  15. GRB 240824A: Swift-XRT observations
  16. GRB 240821A: Swift/UVOT observations of the XRT sources.
  17. GRB 240821A: Swift-XRT observations
  18. GECAM-B observation of a short burst from SGR 1E 1841-045 / Kes 73
  19. GRB 240821A: Fermi GBM Observation
  20. GRB 240821A: EP-FXT follow-up observation and afterglow candidates
  21. GRB 240819A: Swift-XRT observations
  22. EP240820a: EP detection of a fast X-ray transient
  23. GRB 240819A: X-ray follow-up observation with EP-FXT
  24. EP240816b: TRT optical upper limit
  25. EP240802a: Kinder optical, SWIFT-UVOT, and SWIFT-XRT upper limits 6 days after the WXT detection
  26. Konus-Wind detection of GRB 240811A
  27. GRB 240811A: Swift-XRT refined Analysis
  28. Konus-Wind detection of GRB 240809A
  29. Konus-Wind detection of GRB 240807A (a counterpart of EP240807a)
  30. Fermi-LAT gamma-ray observations of IceCube-240808A
  31. GRB 240809A: GIT afterglow observations
  32. GRB 240809A: Tentative redshift from NOT
  33. GRB 240809A: Swift-XRT refined Analysis
  34. GRB 240809A: JinShan optical observations
  35. The EP-WXT trigger 01709018832 on August 7th is likely a flaring star
  36. EP240806a: Gemini North-GMOS spectroscopic redshift of z = 2.818
  37. EP240804a (GRB 240804B): NOT optical observations
  38. EP240806a: LCOGT optical counterpart detection
  39. GRB240805A: Fermi GBM Observation
  40. Konus-Wind detection of GRB 240804B (a counterpart of EP240804a)
  41. GRB 240805B: Swift-XRT refined Analysis
  42. GRB 240805A: Swift-XRT refined Analysis
  43. GRB 240805A: Fermi-LAT detection
  44. EP240804a: LCOGT optical counterpart detection
  45. EP240802a: Time coincidence with GRB 240802A and optical upper limits with Kinder observations
  46. EP240801a: further SAO RAS optical observations
  47. EP240801a: SAO RAS optical observations
  48. EP240801a: follow-up observation with LCOGT
  49. EP240801a: Kinder follow-up observations of the candidate counterpart
  50. EP240801a: TRT optical counterpart detection
  51. GRB 240730A: Swift-XRT refined Analysis
  52. GRB 240715A: Swift-XRT afterglow detection
  53. GRB 240730A: Swift detection of a burst
  54. GRB 240727B: Swift-XRT observations
  55. GRB 240727A: Swift-XRT refined Analysis
  56. GRB 240727B: Fermi GBM Observation
  57. GRB 240727A: TRT optical afterglow detection
  58. Fermi-LAT gamma-ray observations of IceCube-240725A
  59. Fermi-LAT gamma-ray observations of IceCube-240721A
  60. GRB 240720A: Fermi GBM observation
  61. GRB 240718A: Fermi GBM Observation
  62. GRB 240718A: Fermi-LAT Detection
  63. IceCube-Cascade 240714A: X-ray follow-up observation with EP-FXT
  64. Fermi-LAT gamma-ray observations of IceCube-cascade-240714A
  65. GRB 240715A: Swift/UVOT observations of the XRT sources.
  66. GRB 240715A: Swift-XRT observations
  67. GRB240713A: Swift/UVOT Upper LImits
  68. GRB 240715A: GECAM-C detection of a short burst
  69. GRB 240713A: Swift-XRT observations
  70. GRB 240715A: TRT optical upper limit on one Swift/XRT candidate
  71. GRB 240712A: Swift-XRT refined Analysis
  72. GRB 240715A: Fermi GBM Observation
  73. The EP-WXT source triggered on July 14th is likely a flaring star
  74. GRB 240713A: NOT optical upper limits on three EP/FXT candidates
  75. GRB240713A: X-ray follow-up observation with EP-FXT
  76. GRB 240713B: AstroSat CZTI detection of a long burst
  77. GRB240713A: Optical upper limit with Kinder observations
  78. EP240708a: NOT optical observations
  79. EP240708a: Optical upper limits with Kinder observations
  80. EP240703c: Kinder optical follow-up and Swift XRT observations
  81. EP240703a: Kinder optical follow-up observations
  82. EP240703c: EP-WXT detection of an X-ray transient
  83. EP240703a/GRB 240703A: TRT and JinShan decaying optical afterglow candidate
  84. EP240703a: EP-WXT detection of a fast X-ray transient
  85. Konus-Wind detection of GRB 240619A
  86. GRB 240625A: Fermi GBM Observation
  87. EP240625a: EP-WXT detection of a fast X-ray transient
  88. GRB240624A: Fermi GBM Observation
  89. X-ray transient EP240618a: Fermi/GBM non-detection
  90. EP240618a: Swift/XRT upper limit
  91. EP240617a: tentative Swift/XRT detection of the afterglow
  92. GRB 240619A: Swift-XRT probable afterglow detection
  93. GRB 240619A: Fermi GBM Observation
  94. LIGO/Virgo S240615dg: Swift XRT observations, 39 X-ray sources
  95. Fermi trigger No 740430582: Global MASTER-Net observations report
  96. GRB240615A: 1.3m DFOT optical upper limit
  97. EP240617a: EP-WXT detection of a fast X-ray transient
  98. GRB 240615A: Fermi GBM Observation
  99. GRB 240615A: Swift-XRT observations
  100. GRB 240615A: FLWO-1.2m optical upper limits

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