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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"

6791 results found.

  1. GRB 240828A: Swift-XRT afterglow detection
  2. GRB 240825A: further SAO RAS optical observations
  3. GRB 240825A: iTelescope optical observations
  4. GRB 240828B: Swift-XRT afterglow detection
  5. GRB 240828A: Fermi-LAT detection
  6. GRB 240821A: the second and third EP-FXT follow-up observations and afterglow candidates
  7. GRB 240819A: Swift afterglow confirmation
  8. Konus-Wind detection of GRB 240825A (bright/long)
  9. GRB 240825A: Fermi GBM Observation
  10. GRB 240825A: Swift-XRT refined Analysis
  11. GRB 240825A: Fermi-LAT detection
  12. GRB 240824B: Fermi GBM Observation
  13. GRB 240824B: Swift-XRT afterglow detection
  14. GRB 240824A: Swift-XRT observations
  15. GRB 240821A: Swift/UVOT observations of the XRT sources.
  16. GRB 240821A: Swift-XRT observations
  17. GECAM-B observation of a short burst from SGR 1E 1841-045 / Kes 73
  18. GRB 240821A: Fermi GBM Observation
  19. GRB 240821A: EP-FXT follow-up observation and afterglow candidates
  20. GRB 240819A: Swift-XRT observations
  21. EP240820a: EP detection of a fast X-ray transient
  22. GRB 240819A: X-ray follow-up observation with EP-FXT
  23. EP240816b: TRT optical upper limit
  24. EP240802a: Kinder optical, SWIFT-UVOT, and SWIFT-XRT upper limits 6 days after the WXT detection
  25. Konus-Wind detection of GRB 240811A
  26. GRB 240811A: Swift-XRT refined Analysis
  27. Konus-Wind detection of GRB 240809A
  28. Konus-Wind detection of GRB 240807A (a counterpart of EP240807a)
  29. Fermi-LAT gamma-ray observations of IceCube-240808A
  30. GRB 240809A: GIT afterglow observations
  31. GRB 240809A: Tentative redshift from NOT
  32. GRB 240809A: Swift-XRT refined Analysis
  33. GRB 240809A: JinShan optical observations
  34. The EP-WXT trigger 01709018832 on August 7th is likely a flaring star
  35. EP240806a: Gemini North-GMOS spectroscopic redshift of z = 2.818
  36. EP240804a (GRB 240804B): NOT optical observations
  37. EP240806a: LCOGT optical counterpart detection
  38. GRB240805A: Fermi GBM Observation
  39. Konus-Wind detection of GRB 240804B (a counterpart of EP240804a)
  40. GRB 240805B: Swift-XRT refined Analysis
  41. GRB 240805A: Swift-XRT refined Analysis
  42. GRB 240805A: Fermi-LAT detection
  43. EP240804a: LCOGT optical counterpart detection
  44. EP240802a: Time coincidence with GRB 240802A and optical upper limits with Kinder observations
  45. EP240801a: further SAO RAS optical observations
  46. EP240801a: SAO RAS optical observations
  47. EP240801a: follow-up observation with LCOGT
  48. EP240801a: Kinder follow-up observations of the candidate counterpart
  49. EP240801a: TRT optical counterpart detection
  50. GRB 240730A: Swift-XRT refined Analysis
  51. GRB 240715A: Swift-XRT afterglow detection
  52. GRB 240730A: Swift detection of a burst
  53. GRB 240727B: Swift-XRT observations
  54. GRB 240727A: Swift-XRT refined Analysis
  55. GRB 240727B: Fermi GBM Observation
  56. GRB 240727A: TRT optical afterglow detection
  57. Fermi-LAT gamma-ray observations of IceCube-240725A
  58. Fermi-LAT gamma-ray observations of IceCube-240721A
  59. GRB 240720A: Fermi GBM observation
  60. GRB 240718A: Fermi GBM Observation
  61. GRB 240718A: Fermi-LAT Detection
  62. IceCube-Cascade 240714A: X-ray follow-up observation with EP-FXT
  63. Fermi-LAT gamma-ray observations of IceCube-cascade-240714A
  64. GRB 240715A: Swift/UVOT observations of the XRT sources.
  65. GRB 240715A: Swift-XRT observations
  66. GRB240713A: Swift/UVOT Upper LImits
  67. GRB 240715A: GECAM-C detection of a short burst
  68. GRB 240713A: Swift-XRT observations
  69. GRB 240715A: TRT optical upper limit on one Swift/XRT candidate
  70. GRB 240712A: Swift-XRT refined Analysis
  71. GRB 240715A: Fermi GBM Observation
  72. The EP-WXT source triggered on July 14th is likely a flaring star
  73. GRB 240713A: NOT optical upper limits on three EP/FXT candidates
  74. GRB240713A: X-ray follow-up observation with EP-FXT
  75. GRB 240713B: AstroSat CZTI detection of a long burst
  76. GRB240713A: Optical upper limit with Kinder observations
  77. EP240708a: NOT optical observations
  78. EP240708a: Optical upper limits with Kinder observations
  79. EP240703c: Kinder optical follow-up and Swift XRT observations
  80. EP240703a: Kinder optical follow-up observations
  81. EP240703c: EP-WXT detection of an X-ray transient
  82. EP240703a/GRB 240703A: TRT and JinShan decaying optical afterglow candidate
  83. EP240703a: EP-WXT detection of a fast X-ray transient
  84. Konus-Wind detection of GRB 240619A
  85. GRB 240625A: Fermi GBM Observation
  86. EP240625a: EP-WXT detection of a fast X-ray transient
  87. GRB240624A: Fermi GBM Observation
  88. X-ray transient EP240618a: Fermi/GBM non-detection
  89. EP240618a: Swift/XRT upper limit
  90. EP240617a: tentative Swift/XRT detection of the afterglow
  91. GRB 240619A: Swift-XRT probable afterglow detection
  92. GRB 240619A: Fermi GBM Observation
  93. LIGO/Virgo S240615dg: Swift XRT observations, 39 X-ray sources
  94. Fermi trigger No 740430582: Global MASTER-Net observations report
  95. GRB240615A: 1.3m DFOT optical upper limit
  96. EP240617a: EP-WXT detection of a fast X-ray transient
  97. GRB 240615A: Fermi GBM Observation
  98. GRB 240615A: Swift-XRT observations
  99. GRB 240615A: FLWO-1.2m optical upper limits
  100. GRB 240607A: Fermi GBM Observation

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